Comtech EF Data SNM-1001L Installation And Operation Manual
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Comtech EF Data SNM-1001L Installation And Operation Manual

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SNM-1001L
Satellite Modem
Installation and Operation Manual
Part Number MN/SNM1001L.IOM
Revision 1

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  • Page 1 SNM-1001L Satellite Modem Installation and Operation Manual Part Number MN/SNM1001L.IOM Revision 1...
  • Page 3 150W, 48V BUC power supply at maximum load. USES The SNM-1001L Satellite Modem is fitted with two fuses, one each for line and neutral connections. These are contained within the body of the IEC power connector, behind a small plastic flap.

  • Page 4: Ac Power Connector

    3.2.9 AC Power Connector A standard, detachable, non-locking, 3-prong power cord (IEC plug) supplies the Alternating Current (AC) power to the modem. Observe the following: Input Power 55W maximum, 40W typical without BUC power supply. 90 to 132 or 175 to 264 VAC Input Voltage Unit switches ranges automatically Connector Type...

  • Page 5: Installation And Operation Manual

    Comtech EF Data is an ISO 9001 March 17, 2003 Registered Company. Copyright © Comtech EF Data, 2000, 2001, 2002. All rights reserved. Printed in the USA. MULTIMEDIA INTEGRATED DIGITAL ACCESS SYSTEM Comtech EF Data, 2114 West 7th Street, Tempe,...

  • Page 6: Customer Support

    E-Mail can be sent to the Customer Support Department at: service@comtechefdata.com Contact us via the web at www.comtechefdata.com. To return a Comtech EF Data product (in-warranty and out-of-warranty) for repair or replacement: 1. Request a Return Material Authorization (RMA) number from the Comtech EF Data Customer Support Department.

  • Page 7: Table Of Contents

    Telecommunications Terminal Equipment Directive................xvi EMC (Electromagnetic Compatibility)....................xvii Warranty Policy .............................xviii CHAPTER 1. INTRODUCTION .....................1–1 Overview ............................1–1 Options Summary ........................1–2 Comtech EF Data Part Numbers....................1–3 FAST Accessible Options ......................1–4 Compatibility..........................1–5 Description of the Modulator..................... 1–5 1.6.1 Overview..........................1–5 1.6.2 Functional Description......................
  • Page 8 SNM-1001L Satellite Modem Revision 1 Preface MN/SNM1001L.IOM 1.8.1 Overview..........................1–11 1.8.2 Functional Description......................1–12 Dimensional Envelope ......................1–14 1.10 New in this Release........................1–15 CHAPTER 2. INSTALLATION/ UPGRADES ................2–1 Unpacking............................ 2–1 Installation ........................... 2–2 2.2.1 Modem Installation (Optional)....................2–2 Software and Hardware Installation/Upgrades ............... 2–4 2.3.1...
  • Page 9 MODEM TYPE....................5–1 CHAPTER 5. Modem Type..........................5–1 5.1.1 AUPC Operation (with Reed-Solomon) ................5–2 5.1.2 Closed Network Operation (Comtech EF Data) ..............5–2 Custom Operation........................5–3 Reed-Solomon Modes ......................... 5–4 CHAPTER 6. CLOCKING AND RX BUFFERING SETTINGS..........6–1 Clocking Options......................... 6–1 6.1.1...
  • Page 10 SNM-1001L Satellite Modem Revision 1 Preface MN/SNM1001L.IOM Introduction..........................7–1 Coding ............................7–2 Turbo Product Codec (Hardware Option) ................7–2 7.3.1 Introduction........................... 7–2 7.3.2 Mod/Demod Processing Delay ..................... 7–3 7.3.3 Comparison of all TPC Modes....................7–4 Uncoded Operation (No FEC) ....................7–5 SYSTEM CHECKOUT..................8–1...
  • Page 11 SNM-1001L Satellite Modem Revision 1 Preface MN/SNM1001L.IOM 12.2 Variable Data Rates ........................12–5 BUC FSK COMMUNICATIONS ..............13–1 CHAPTER 13. 13.1 Introduction..........................13–1 13.1.1 Transmission Interface......................13–2 13.2 Message Structure........................13–2 13.2.1 Command Message Structure (IDU to ODU)..............13–2 13.2.2 Response Message Structure (BUC to IDU)............... 13–3 13.3...
  • Page 12 SNM-1001L Satellite Modem Revision 1 Preface MN/SNM1001L.IOM A.5.11 Interleaver (Reed-Solomon Codec)..................A–9 A.5.12 Modulator Transmit Frequency (IF) ..................A–9 A.5.13 Transmit Frequency Change Time..................A–9 A.5.14 Modulator Transmit IF Output Switch................. A–9 A.5.15 Modulator Transmit IF Power....................A–9 A.5.16 Modulator Power Offset..................... A–10 A.5.17...
  • Page 13 SNM-1001L Satellite Modem Revision 1 Preface MN/SNM1001L.IOM Acquisition Time ........................A–22 A.9.1 Receive Carrier Acquisition Range..................A–23 A.9.2 Receive Carrier Reacquisition ................... A–23 A.9.3 AGC Output ........................A–23 A.9.4 Doppler Tracking Performance..................A–23 A.10 Interface Specifications......................A–24 A.10.1 TX Clock Switching Due to Failure of Selected Clock ............. A–24 A.10.2...
  • Page 14 SNM-1001L Satellite Modem Revision 1 Preface MN/SNM1001L.IOM APPENDIX B. REMOTE CONTROL OPERATION.............. B–1 B.1 General ............................. B–1 B.2 Message Structure ........................... B–2 B.2.1 Start Character..........................B–2 B.2.2 Device Address .......................... B–2 B.2.3 Command/Response........................B–3 B.2.4 End Character ..........................B–4 B.3 Configuration Commands/Responses.................... B–5 B.3.1 Modulator Configuration Commands ..................
  • Page 15 SNM-1001L Satellite Modem Revision 1 Preface MN/SNM1001L.IOM Burst Mode Demodulator: Theory of Operation ..............C–7 C.3.1 Burst Mode........................... C–7 Burst Mode Demodulator: Specifications................C–8 C.4.1 Digital Data Rate........................C–8 C.4.2 Demodulation and FEC Decoding Types ................C–8 C.4.3 Descrambling Types ......................C–8 C.4.4...
  • Page 16 FIGURE 15-2.REED-SOLOMON CODEC BLOCK DIAGRAM .................15–2 FIGURE 15-3. REED-SOLOMON ENCODER SECTION BLOCK DIAGRAM ..........15–3 FIGURE 15-4. REED-SOLOMON CODE PAGE FORMAT ................15–4 FIGURE 15-5. REED-SOLOMON DECODER SECTION BLOCK DIAGRAM ..........15–5 FIGURE A-1. CARRIER LEVEL VS SYMBOL RATE..................A–18 FIGURE C-1. SNM-1001L BURST MODE FAULT TREE ................C–13...
  • Page 17 SNM-1001L Satellite Modem Revision 1 Preface MN/SNM1001L.IOM Tables TABLE 1-1. FAST OPTIONS AND REQUIRED CONFIGURATIONS ...............1–4 TABLE 3-1. MODEM REAR PANEL CONNECTORS..................3–2 TABLE 3-2. REMOTE CONNECTOR AND PINOUTS (J6).................3–3 TABLE 3-3. FAULT CONNECTOR AND PINOUTS (J7) ..................3–4 TABLE 3-4. 25-PIN D CONNECTOR PINOUTS ....................3–6 TABLE 3-5.

  • Page 18: About This Manual

    Preface MN/SNM1001L.IOM About this Manual This manual provides installation and operation information for the Comtech EF Data SNM-1001A satellite modem. This is a technical document intended for earth station engineers, technicians, and operators responsible for the operation and maintenance of the SNM-1001A.
  • Page 19 Reporting Comments or Suggestions Concerning this Manual Comments and suggestions regarding the content and design of this manual will be appreciated. To submit comments, please contact the Comtech EF Data Customer Support Department.

  • Page 20: Electrical Safety

    The equipment is rated for operation over the range 85 to 264 volts AC. It has a maximum power consumption of 60 watts. USES The SNM-1001L Satellite Modem is fitted with two fuses, one each for line and neutral connections. These are contained within the body of the IEC power connector, behind a small plastic flap.

  • Page 21: Telecommunications Terminal Equipment Directive

    The equipment is not designed for connection to power system that has no direct connection to ground. The SNM-1001L is shipped with a line inlet cable suitable for use in the country of operation. If it is necessary to replace this cable, ensure the replacement has an equivalent specification.

  • Page 22: Emc (Electromagnetic Compatibility)

    SNM-1001L Satellite Modem Revision 1 Preface MN/SNM1001L.IOM EMC (Electromagnetic Compatibility) In accordance with European Directive 89/336/EEC, the SDM-300L3 Satellite Modem has been shown, by independent testing, to comply with the following standards: Emissions: EN 55022 Class B - Limits and methods of measurement of radio interference characteristics of Information Technology Equipment.

  • Page 23: Warranty Policy

    Disclaimer Comtech EF Data has reviewed this manual thoroughly in order that it will be an easy-to- use guide to your equipment. All statements, technical information, and recommendations in this manual and in any guides or related documents are believed...

  • Page 25: Chapter 1. Introduction

    Chapter 1. INTRODUCTION SNM-1001L Satellite Modem The SNM-1001L Satellite Modem is a dual function modem: it can operate in burst and continuous mode. Overview • Burst mode operation: 19.2 kbps and/or 57.6 kbps, 1/2 rate QPSK • 2.4 kbps to 5.0 Mbps Continuous Mode •...

  • Page 26: Options Summary

    Remote Remote Port Port SNM-1001L Satellite Modem Figure 1-1. Block Diagram Options Summary A summary of the available options for the unit is provided. Contact Comtech EF Data Customer Support for upgrade information. Option Description /Comment Availability Install Option Single Data/Code Rate FAST ≤...

  • Page 27: Comtech Ef Data Part Numbers

    No BUC) ODU DC Power: 24V or 48V. Primary 100W @ 24V Factory input = AC Only 150W @ 48V Comtech EF Data Part Numbers Part No. Description Remarks PL/9066-3 RX only IF 1.0 ppm Use with internal reference LNBs.

  • Page 28: Fast Accessible Options

    MN/SNM1001L.IOM FAST Accessible Options Comtech EF Data FAST system allows immediate implementation of different options through the user interface keypad. Some FAST options are available through the basic platform unit, while others require that the unit be equipped with optional hardware or that the hardware be installed in the field.

  • Page 29: Compatibility

    SNM-1001L Satellite Modem Revision 1 Introduction MN/SNM1001L.IOM Compatibility The SNM-1001L is functionally compatible with many Comtech EF Data modems. When properly configured, the unit will interoperate with the following Comtech EF Data modems: • • CDM-550/550T (Turbo only) SDM-650B •...

  • Page 30: Description Of Modulation Types

    I and Q channels of the modulator. The baseband processing for the SNM-1001L does not use the digital modulation. Instead, the baseband Nyquist filtered I and Q signals pass through D/A converters to drive an analog vector modulator.

  • Page 31: Bpsk Encoding

    SNM-1001L Satellite Modem Revision 1 Introduction MN/SNM1001L.IOM • 8-PSK: 8 discrete phase angles represent the 8 possible states of a symbol. Note: The code rate determines the number of symbols per bit. 1.6.3.1 BPSK Encoding The modulator converts transmitted baseband data into a modulated BPSK carrier at 2.4 kbps to 1.25 Mbps (1/2 rate).

  • Page 32: Psk Encoding

    SNM-1001L Satellite Modem Revision 1 Introduction MN/SNM1001L.IOM 1.6.3.3 Offset QPSK Encoding The modulator PCB converts the transmitted baseband data into a modulated Offset QPSK carrier within the same parameters as QPSK. The Offset QPSK modulation is mainly different from QPSK by offsetting the I and Q channel modulation signals.

  • Page 33: Description Of The Demodulator

    SNM-1001L Satellite Modem Revision 1 Introduction MN/SNM1001L.IOM Description of the Demodulator A block diagram of the demodulator is shown in Figure 1-2. 1.7.1 Overview The demodulator converts PSK modulated carriers within the 950 to 1750 MHz range to a demodulated baseband data stream. The converted modulation types are BPSK, QPSK, Offset QPSK, and 8-PSK.

  • Page 34: Functional Description

    SNM-1001L Satellite Modem Revision 1 Introduction MN/SNM1001L.IOM 1.7.2 Functional Description The demodulator functions as an advanced, digital, coherent-phase-lock receiver and decoder. Demodulator faults also are reported to the front panel. The demodulator consists of the following basic subsections. • Digital Costas Loop •...

  • Page 35: Description Of Monitor & Control

    SNM-1001L Satellite Modem Revision 1 Introduction MN/SNM1001L.IOM The digital clock loop, in conjunction with another DDS, performs the clock recovery function. The clock loop consists of a phase detector, loop filter, and DDS, all implemented digitally. The DDS performs the function of a VCO in an analog implementation.

  • Page 36: Functional Description

    SNM-1001L Satellite Modem Revision 1 Introduction MN/SNM1001L.IOM 1.8.2 Functional Description The M&C card is composed of the following subsections: • Microcontroller with Universal Asynchronous Receiver/Transmitter (UART) • Digital-to-Analog Converter (DAC) • Read Only Memory (ROM) • Analog-to-Digital Converter (ADC) •...
  • Page 37 SNM-1001L Satellite Modem Revision 1 Introduction MN/SNM1001L.IOM The heart of the M&C card is the Dallas 80C310 microcontroller operating at 11 MHz. This microcontroller contains 256 Kbytes of internal RAM. The ROM at U8 is 29F040 (512 kbytes). ROM access times must be equal to or greater than 150 ns. The RAM size can be 8 or 32 Kbytes.

  • Page 38: Dimensional Envelope

    SNM-1001L Satellite Modem Revision 1 Introduction MN/SNM1001L.IOM Dimensional Envelope Refer to Figure 1-2 for the unit’s dimensional envelope drawing. Note: Dimensions are listed in inches and centimeters are in parentheses. 19.1 1.75 (48.72 (4.4 19.0 17.0 (48.26 (43.18) 1.25 (3.2 Figure 1-4.

  • Page 39: New In This Release

    Revision 1 of this document incorporates the foillowing changes: • Added 57.6 kbps throughtout the manual. • Changed SNM-1001L3 to SNM-1001L from the Opening Screen • Added Continuous Mode Data Rates and Burst Mode Data Rate in Chapter 3. •...
  • Page 40 SNM-1001L Satellite Modem Revision 1 Introduction MN/SNM1001L.IOM This page is intentionally left blank. 1–16...

  • Page 41: Chapter 2. Installation/ Upgrades

    Chapter 2. INSTALLATION/ UPGRADES The equipment contains parts and assemblies sensitive to damage by Electrostatic Discharge (ESD). Use ESD precautionary procedures when touching, removing, or inserting PCBs. CAUTION Unpacking The modem and manual are packaged in pre-formed, reusable, cardboard cartons containing foam spacing for maximum shipping protection.

  • Page 42: Installation

    SNM-1001L Satellite Modem Revision 1 Installation MN/SNM1001L.OM Installation The modem arrives fully assembled from the factory. After unpacking the modem, install the modem as follows: 2.2.1 Modem Installation (Optional) Refer to Figure 2-1. Use the following mounting kit, KT/6228-1. Optional: Mounting KIT, KT/6228-1 (Modem to Equipment Rack)
  • Page 43 SNM-1001L Satellite Modem Revision 1 Installation MN/SNM1001L.OM Equipment Rack Mounting Rail #10 Socket head screw BRACKET BOLTS Support Bracket * Note: Components of mounting kit KT/6228-1 Figure 2-1. Installation of the Optional Mounting Bracket KT/6228-1 2–3...

  • Page 44: Software And Hardware Installation/Upgrades

    SNM-1001L Satellite Modem Revision 1 Installation MN/SNM1001L.OM Software and Hardware Installation/Upgrades 2.3.1 Reed-Solomon PCB The TX/RX Reed-Solomon PCBs are installed in the same slots as the Turbo module. Do not mix Reed-Solomon PCBs with Turbo PCB. Damage to the equipment may be the result.

  • Page 45: Figure 2-2. Reed-Solomon Codec Installation

    SNM-1001L Satellite Modem Revision 1 Installation MN/SNM1001L.OM 4. After completing the above installation procedure turn on the modem. If the Reed-Solomon PCB was installed properly, the Utility Interface/Interface Module menu will display “OPT:Reed-Solomon.” Reed-Solomon Cards (TX or RX in Either Slot) Figure 2-2.

  • Page 46: Turbo Codec Installation

    SNM-1001L Satellite Modem Revision 1 Installation MN/SNM1001L.OM 2.3.2 Turbo Codec Installation The Turbo Card is installed in the same slots as the Reed-Solomon PCBs. While the Reed- Solomon uses two cards (TX and RX), the Turbo Codec uses only a single card.

  • Page 47: Figure 2-3. Turbo Codec Installation

    SNM-1001L Satellite Modem Revision 1 Installation MN/SNM1001L.OM 5. Turn on the AC power. Modem will reinitialize. Notes: 1. In this configuration, the Modem allows only Data Rates and Formats valid for Turbo. 2. Open-network modem types cannot be selected. Turbo Codec Installed Figure 2-3.

  • Page 48: Data I/O Interface Connector (J8) Removal/Installation

    SNM-1001L Satellite Modem Revision 1 Installation MN/SNM1001L.OM Data I/O Interface Connector (J8) Removal/Installation Note: The following procedures outline the removal and installation of the Data I/O connector (J8). These procedures are written with the assumption that the same configured connector will be reinstalled.

  • Page 49: Hardware Upgrades

    SNM-1001L Satellite Modem Revision 1 Installation MN/SNM1001L.OM For Ribbon-Configured Connector Figure 2-4. Data I/O Connector (J8) Removal/Installation Hardware Upgrades 2.5.1 Main PCB Firmware Chips The main PCB has one field-changeable flash memory chip for the M&C firmware. If necessary, this chip can be removed and a new chip added to allow for additional options, enhancements, or repairs.

  • Page 50: Figure 2-5. Main Board Field-Changeable Chips (Shown With Overhead Card Removed)

    SNM-1001L Satellite Modem Revision 1 Installation MN/SNM1001L.OM Figure 2-5. Main Board Field-Changeable Chips (Shown with Overhead Card Removed) 2–10...

  • Page 51: Flash Upgrading

    IMPORTANT The SNM-1001L provides for flash upgrading the M&C firmware or the BULK firmware. Note: While the M&C and BULK firmware downloads are independent processes, the modem may have to be upgraded to the latest releases of both the M&C and BULK for proper function.

  • Page 52: 2.6.1 Downloading Flash Updates From The Web

    MN/SNM1001L.OM 2.6.1 Downloading Flash Updates from the Web The latest firmware releases and a free software utility are available on the Comtech EF Data web site (http://www.comtechefdata.com). This utility is designed to run under Windows 95/98 or Windows NT/2000/XP and provides all of the support required to perform a Comtech EF Data firmware reflash.

  • Page 53: Chapter 3. Connector Pinouts

    Chapter 3. CONNECTOR PINOUTS Connector Overview The rear panel connectors provide all necessary external connections between the modem and other equipment. Table 3-1 lists these connectors and Figure 3-1 show their locations. DATA I/O Figure 3-1. Rear Panel 3–1...

  • Page 54: Table 3-1. Modem Rear Panel Connectors

    SNM-1001L Satellite Modem Revision 1 Connector Pinouts MN/SNM1001L.IOM Table 3-1. Modem Rear Panel Connectors Ref. Desig. Name Connector Type Function TX/IF OUTPUT Type N , Female RF Output EXT REF BNC, Female EXT REF IN RF IF INPUT Type F, Female RF Input 75Ω...

  • Page 55: Connector Description

    SNM-1001L Satellite Modem Revision 1 Connector Pinouts MN/SNM1001L.IOM Connector Description 3.2.1 Remote Connector and Pinouts (J6) The remote connector is a 9-pin subminiature female D connector (J6) located on the rear panel of the modem. Screw locks are provided for mechanical security of the mating connector.

  • Page 56: Fault Connector And Pinouts (J7)

    SNM-1001L Satellite Modem Revision 1 Connector Pinouts MN/SNM1001L.IOM 3.2.2 Fault Connector and Pinouts (J7) The fault connector provides Form C contact closures for fault reporting. The three Form C summary fault contacts, ratings 1A maximum at 24 VDC, 0.5A at 120 VAC, are Modulator, Demodulator, and Common Equipment.

  • Page 57: Data I/O Interface Connector (J8)

    SNM-1001L Satellite Modem Revision 1 Connector Pinouts MN/SNM1001L.IOM 3.2.3 Data I/O Interface Connector (J8) The Data I/O interface connector conducts data input and output signals to and from the modem, and connects to the customer’s terrestrial equipment, breakout panel, or protection switch.

  • Page 58: Table 3-4. 25-Pin D Connector Pinouts

    SNM-1001L Satellite Modem Revision 1 Connector Pinouts MN/SNM1001L.IOM Table 3-4. 25-Pin D Connector Pinouts 25-Pin D Connector Pin # EIA-422 EIA-232 V.35 SHLD SHLD SHLD SD-A SD-A RD-A RD-A RS-A CS-A DM-A SIGGND SIGGND SIGGND RR-A RLSD RT+B SCR+B RR-B...

  • Page 59: Table 3-5. 34-Pin Winchester Connector Pinouts (V.35)

    3. Grounding pin CC at the Fireberd interface will change the Fireberd  to a DCE device. 4. Comtech EF Data uses the CC and DD for the input master clock (same as the external clock input to the modem). To input an external clock, change the jumper to positions 1 and 2 (the pin closest to the Winchester connector).

  • Page 60: Table 3-6. 37-Pin Connector Pinouts (Optional)

    SNM-1001L Satellite Modem Revision 1 Connector Pinouts MN/SNM1001L.IOM Table 3-6. 37-Pin Connector Pinouts (Optional) Pin # EIA-422/MIL-188-144 1, 19 Shield SD-A ST-A RD-A RS-A RT-A CS-A DM-A RR-A MC-A TT-A 20, 37 SIGGND SD+B ST+B RD+B RS+B RT+B CS+B DM+B...

  • Page 61: Auxiliary 1 Connector And Pinouts (J9)

    SNM-1001L Satellite Modem Revision 1 Connector Pinouts MN/SNM1001L.IOM 3.2.4 Auxiliary 1 Connector and Pinouts (J9) The auxiliary 1 (AUX 1) connector provides: • MOD and DEMOD (TTL) faults • Satellite clock • Satellite I&Q • Automatic Gain Control (AGC) output voltage The faults are open collector levels that indicate a modulator or demodulator failure.

  • Page 62: Alarms Connector And Pinouts (J10)

    SNM-1001L Satellite Modem Revision 1 Connector Pinouts MN/SNM1001L.IOM 3.2.5 Alarms Connector and Pinouts (J10) The alarm connector provides Form C contact closures for alarm reporting. The two Form C summary fault contacts are Modulator and Demodulator. The alarm connection is a 9-pin female D connector (J10) located on the rear panel of the modem.

  • Page 63: Ac Power Connector

    SNM-1001L Satellite Modem Revision 1 Connector Pinouts MN/SNM1001L.IOM 3.2.9 AC Power Connector A standard, detachable, non-locking, 3-prong power cord (IEC plug) supplies the Alternating Current (AC) power to the modem. Observe the following: 55W maximum, 40W typical Input Power 90 to 132 or 175 to 264 VAC...
  • Page 64 SNM-1001L Satellite Modem Revision 1 Connector Pinouts MN/SNM1001L.IOM This page is intentionally left blank. 3–12...

  • Page 65: Chapter 4. Front Panel Operation

    POWER ON ENTER ENTER RECEIVE RECEIVE T RANSMIT TER ON TRANSMIT TER ON SNM-1001L COMMON CA RRIER DETECT CARRIER DETE CT CLEAR CLEAR Satellite Modem S N M - 1 0 1 0 D a t a C o n t r o l M o d e m...

  • Page 66: Status • Alarms The Indicators Are Defined In Table 4-1 As Follows

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM 4.1.1 LED Indicators The 10 LEDs on the front panel indicate: • General modem summary faults • Status • Alarms The indicators are defined in Table 4-1 as follows: Table 4-1. LED Indicators...

  • Page 67: Front Panel Keypad

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM 4.1.2 Front Panel Keypad The front panel keypad permits local operation of the modem. The keypad consists of six keys (Figure 4-2). ENTER CLEAR Figure 4-2. Keypad Each key provides one or more logical functions. These functions are defined in the following table.

  • Page 68: Menu System

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM Menu System Note: The menus show features and options that are not available. However, they are shown to preserve the menu structure and reserve the structure for the future. This does not imply an intent or obligation to add these features or options in the future.

  • Page 69: Revision Emulation

    1. Figure 4-3 list the front panel menu window selections. 2. Comtech EF Data recommends that selection of the desired Modem Type be made prior to making any other setting. This procedure is located in the Utility Modem Type menu.

  • Page 70: Front Panel Operation

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM 4.2.2 Menu Tree SELECT (4.3) CONFIGURATION (4.3.1) ASSIGNED TRANSMIT FILTERS CONFIGURATION MONITOR MODULATOR TX-X CODE/DATA RATE TX TERMINAL LO DEMODULATOR TX-IF FREQUENCY MOD POWER OFFSET FAULTS/ALARMS TX TERMINAL FREQ MODULATOR TYPE...

  • Page 71: Opening Screen

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM OPENING SCREEN This screen is displayed whenever power is first applied to the unit. SNM-1001L CUSTOM VER: X.X.X Press [→] key to go to the any of the following FUNCTIONAL SELECT menu screens •...
  • Page 72 SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM 4.3.1.1 FUNCTION SELECT: CONFIGURATION: MODULATOR CONFIGURATION MODULATOR Press <ENTER > to review or edit the following sub-menus. FUNCTION SELECT: CONFIGURATION: MODULATOR: TX-X CODE/DATA RATE TX-A QPSK 64.000 Kbps TX-B QPSK 1/2 128.000 Kbps...
  • Page 73 SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM Upon entry, the current transmitter rate is displayed with the flashing cursor on the first character of the code rate on line 1. Line 2 displays the data rate. Press [←] or [→] to make the selection.

  • Page 74: Tx-If Frequency

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: CONFIGURATION: MODULATOR: TX-IF FREQUENCY (CONDITIONAL) TX-IF FREQUENCY 1200.0000 MHz Conditional: This menu is displayed when LO is programmed to 0 under Utility: Modulator: TX Terminal LO menu. IMPORTANT Programs the modulator transmit frequency between 950 and 1750 MHz, in 100 Hz steps.

  • Page 75: Tx-If Output

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: CONFIGURATION: MODULATOR: TX-IF OUTPUT TX-IF OUTPUT Programs the modulator output On or Off. Upon entry, the current status of the output is displayed. Press [↑] or [↓] to make the selection. Press <ENTER> to execute the change.

  • Page 76: Diff. Encoder

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: CONFIGURATION: MODULATOR: SCRAMBLER SCRAMBLER Programs the scrambler On or Off. Upon entry, the current status of the scrambler is displayed. Press [↑] or [↓] to make the selection. Press <ENTER> to execute the change.

  • Page 77: Carrier Mode

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: CONFIGURATION: MODULATOR: CARRIER MODE CARRIER MODE NORMAL-MODULATED Programs the modem for alternate carrier modes. All modes, except Normal-Modulated are Test Modes. Four modes of operation are available: NORMAL-MODULATED This mode is normally selected.

  • Page 78: Fsk Output

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: CONFIGURATION: MODULATOR: FSK OUTPUT FSK OUTPUT Note: FSK is operational only with a BUC or ODU that incorporates FSK capabilities. Programs the FSK Output On or Off. Upon entry, the current status of the FSK Output is displayed.

  • Page 79: Odu Output Delay

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: CONFIGURATION: MODULATOR: ODU OUTPUT DELAY ODU OUTPUT DELAY 00.00 MIN SEC Programs the ODU Output delay with 0.0 to 20.00 minutes. At power up, the M&C delays carrier turn On by the programmed time. During output delay timeout, the front panel carrier On LED flashes and the ODU output delay screen shows the remaining delay time.

  • Page 80: Rs Encoder

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: CONFIGURATION: MODULATOR: RS ENCODER (CONDITIONAL) RS ENCODER Conditional: Reed-Solomon option only. IMPORTANT Programs the Reed-Solomon Encoder On or Off. Upon entry, the current status of the Reed-Solomon encoder is displayed. Press [↑] or [↓] to make the selection.
  • Page 81 SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM 4.3.1.2 FUNCTION SELECT: CONFIGURATION: DEMODULATOR CONFIGURATION DEMODULATOR Press <ENTER> to review or edit the following sub-menus. FUNCTION SELECT: CONFIGURATION: DEMODULATOR: RX-X CODE/DATA RATE RX-A QPSK 1/2 64.000 Kbps RX-B QPSK 1/2 128.000 Kbps...
  • Page 82 SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM Upon entry, the current transmitter rate is displayed with the flashing cursor on the first character of the code rate on line 1. Line 2 displays the data rate. Press [←] or [→] to make the selection.

  • Page 83: Rx Terminal Frequency

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: CONFIGURATION: DEMODULATOR: RX-IF FREQUENCY (CONDITIONAL) RX-IF FREQUENCY 1200.0000 MHz Conditional: This menu is displayed when LO is programmed to 0 under Utility: Demodulator: RX Terminal LO menu. IMPORTANT Programs the demodulator receive frequency between 950 and 1750 MHz, in 100 Hz steps.

  • Page 84: Diff. Decoder

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT:CONFIGURATION:DEMODULATOR: DESCRAMBLER DESCRAMBLER Programs the descrambler On or Off. Upon entry, the current status of the descrambler is displayed. Press [↑] or [↓] to make the selection. Press <ENTER> to execute the change.

  • Page 85: Figure 4-4. Rf Loopback

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM Note: RF loopback nullifies IF loopback. Upon entry, the current status of the RF loopback is displayed. Press [↑] or [↓] to make the selection. Press [ENTER] to execute the change.

  • Page 86: Figure 4-5. If Loopback

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM Note: IF loopback nullifies RF loopback. C U S T O M E R T R A N S M I T R F DATA ENCODER/ D A T A INTERFACE...

  • Page 87: Sweep Center

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: CONFIGURATION: DEMODULATOR: SWEEP CENTER SWEEP CENTER 0 Hz Programs the sweep center frequency for the directed sweep function. When in directed sweep, the value from the sweep monitor screen (when the modem was last locked) should be entered for the sweep center frequency.

  • Page 88: Lnb Power

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: CONFIGURATION: DEMODULATOR: REACQUISITION REACQUISITION 0 SECONDS Programs the sweep reacquisition mode time duration. This is the time that the modem will remain in a narrow sweep after loss of acquisition. After this timer runs out, the modem will return to the normal acquisition sweep.

  • Page 89: Lnb 10 Mhz Ref

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: CONFIGURATION: DEMODULATOR: LNB 10 MHZ REF LNB 10 MHz REF Programs the LNB 10 MHz REF to On or OFF. The LNB 10 MHz reference is transmitted out the center conductor of the RF-IF connector.

  • Page 90: Tx Clock Source

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM 4.3.1.3 FUNCTION SELECT: CONFIGURATION INTERFACE CONFIGURATION INTERFACE Press <ENTER > to review or edit the following sub-menus. FUNCTION SELECT: CONFIGURATION: INTERFACE: TX CLOCK SOURCE TX CLOCK SOURCE TX TERRESTRIAL Programs the clock source for the modem transmitter clock to the following...

  • Page 91: Tx Clock Phase

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: CONFIGURATION: INTERFACE: TX CLOCK PHASE TX CLOCK PHASE AUTO Programs the TX clock phase to AUTO, NORMAL, or INVERT. Note: AUTO is the default. Upon entry, the current setting of the TX clock phase is displayed. Press [↑] or [↓] to make the selection.

  • Page 92: Buffer Clock

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: CONFIGURATION: INTERFACE: BUFFER CLOCK BUFFER CLOCK RX (SATELLITE) Programs the interface buffer output clock to one of the following modes: Sets the output buffer clock to the satellite clock.

  • Page 93: Figure 4-6. Baseband Loopback

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: CONFIGURATION: INTERFACE: B-BAND LOOP BACK B-BAND LOOP BACK This is a Test Mode. IMPORTANT Programs the modem for baseband loopback operation. When baseband loopback is turned on, the data and timing signals are switched from the demodulator to the modulator on the modem side of the interface.

  • Page 94: Figure 4-7. Interface Loopback

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: CONFIGURATION: INTERFACE: INTRFC LOOP BACK (CONDITIONAL) INTRFC LOOP BACK This is a Test Mode. Conditional: This menu is only available when the overhead interface PCB or Reed-Solomon PCB is installed.

  • Page 95: Buffer Size

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: CONFIGURATION: INTERFACE: BUFFER SIZE (CONDITIONAL) Conditional: The Bits or Milliseconds menu is displayed depending upon whether Bits or Milliseconds is selected under the Utility: Interface Buffer Program menu. IMPORTANT...

  • Page 96: Loop Timing

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: CONFIGURATION: INTERFACE: LOOP TIMING LOOP TIMING The On setting programs the transmit clocking to the RX satellite clock. TX and RX data rates must be equal unless the asymmetrical loop timing (ASLT) option is enabled. SCT is phase locked to the RX Satellite clock.
  • Page 97 SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM 4.3.1.4 Function SELECT: CONFIGURATION: LOCAL AUPC (Conditional) CONFIGURATION LOCAL AUPC Conditional: This menu is displayed when Local Modem AUPC = ON located under the Utility: Modem Type menu. IMPORTANT The menu is available in several modes: Self-Monitoring AUPC with 1 Modem: In this mode ASYNC is not used.

  • Page 98: Nominal Power

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: CONFIGURATION: LOCAL AUPC: NOMINAL POWER (CONDITIONAL) NOMINAL POWER -10.0 dBm Conditional: This menu is displayed when Local Modem AUPC = ON located under the Utility: Modem Type menu. IMPORTANT Programs the nominal power value of the AUPC.

  • Page 99: Maximum Power

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: CONFIGURATION: LOCAL AUPC: MAXIMUM POWER (CONDITIONAL) MAXIMUM POWER -5.0 dBm Conditional: This menu is displayed when Local Modem AUPC = ON located under the Utility: Modem Type menu. IMPORTANT Programs the maximum power level of the AUPC.

  • Page 100: Tracking Rate

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: CONFIGURATION: LOCAL AUPC: TRACKING RATE (CONDITIONAL) TRACKING RATE 5.0 dB/Min Conditional: This menu is displayed when Local Modem AUPC = ON located under the Utility: Modem Type menu. IMPORTANT Programs the maximum tracking rate of the AUPC.

  • Page 101: Remote Cl Action

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT:CONFIGURATION:LOCAL AUPC: REMOTE CL ACTION (CONDITIONAL) REMOTE CL ACTION HOLD Conditional: This menu is displayed when Local Modem AUPC = ON located under the Utility: Modem Type menu. IMPORTANT Programs the Remote Carrier Loss action (CL) for HOLD, NOMINAL, or MAXIMUM. The modulator carrier at the local end moves to this value upon carrier loss at the remote end.

  • Page 102: Function Select: Configuration: Recall

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM 4.3.1.6 FUNCTION SELECT: CONFIGURATION: RECALL CONFIGURATION RECALL CONFIGURATION RECALL: 1, 2, 3, 4 or 5 The Configuration Recall menu allows the user to recall a previously saved configuration setup. ↑ ↓...

  • Page 103: Function Select: Monitor: Corrected Ber

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: MONITOR: CORRECTED BER CORRECTED BER Displays the current corrected BER or “No Data” (if carrier is not locked). Range: 1.0 E-3 to 1.0 E-12. Notes: 1. Low limit is based on performance.

  • Page 104: Function Select: Monitor: Sweep Frequency

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM Displays the current receive signal level. Range: -135 dBm + 10 log (SR) to -85 dBm + 10log (SR) Press[←] or [→] to move the flashing cursor, and [↑] or [↓] to increment or decrement the selected kbps.

  • Page 105: Function Select: Monitor: Lnb Current

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM Conditional: This menu available only when the optional Overhead Card is installed. IMPORTANT Displays the current framing pattern bit error rate or “No Data” (if carrier is not locked). Monitors the currently selected READ_ERROR function.

  • Page 106: Function Select: Monitor: Odu Current

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: MONITOR: ODU CURRENT ODU CURRENT XXXX mA Monitors the ODU current or “ODU POWER OFF.” Current displayed is 0 to 5000 mA in 1 mA increments. FUNCTION SELECT: MONITOR: ODU VOLTAGE ODU VOLTAGE XX.X VOLTS...
  • Page 107 SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: MONITOR: ODU OUTPUT LEVEL (OPTIONAL) (CONDITIONAL) ODU OUTPUT LEVEL xx.xx/xx.xxT dBm Conditional: This menu is displayed when FSK and ODU POWER SUPPLY are On, under the Configuration: Modulator menu, and Power Leveling is On under the Utility: Outdoor Unit menu.
  • Page 108 SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: MONITOR: ODU PLL LOCK (CONDITIONAL) ODU PLL LOCK OK/UNLOCKED Conditional: This menu is displayed when FSK and ODU POWER SUPPLY are ON under the Configuration: Modulator menu. IMPORTANT Displays the ODU PLL Lock status of an FSK capable BUC. The ODU PLL requires that the ODU 10 MHz reference is On under the Configuration: Modulator menu.

  • Page 109: Function Select: Faults/Alarms

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: MONITOR: TX L-BAND FREQ (CONDITIONAL) TX L-Band FREQ 1200.0000 MHz Conditional: This menu is displayed when the TX Terminal LO (frequency) and Mix are programmed under the Utility: Modulator TX Terminal LO menu.

  • Page 110: Function Select: Faults/Alarms: Modulator

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM Unlike faults, alarms do not cause switching to occur. To display labels for individual faults or alarms, press <ENTER>. Press [←] or [→] to move the flashing cursor to make the selection. The label for that Fault/Alarm is then displayed on line 1 of the display.

  • Page 111: Function Select: Faults/Alarms: Tx Interface

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: FAULTS/ALARMS: TX INTERFACE TX INTERFACE -------- TX DROP Not Used Not Used TX DATA/AIS TX CLK PLL Transmitter phase-locked loop fault. Indicates the transmitter Phase-Locked Loop (PLL) is not locked.

  • Page 112: Function Select: Faults/Alarms: Outdoor Unit

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: FAULTS/ALRMS: COMMON COMMON ------- BATTERY/CLOCK Battery or clock fault. -12V power supply fault. -12V SUPPLY +12V SUPPLY +12V power supply fault. +5V SUPPLY +5V power supply fault. Built in self test fault.

  • Page 113: Function Select: Stored Flts/Alms

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM 4.3.4 FUNCTION SELECT: STORED FLTS/ALMS FUNCTION SELECT STORED FLTS/ALMS Press <ENTER > to review or edit the following sub-menus. The modem stores the first 10 (Flt0 through Flt9) occurrences of fault status changes in each of the following major fault categories: •...
  • Page 114 SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: STORED FLTS/ALMS: MODULATOR MODULATOR STORED TIME/DATE Displays the stored date and time of a fault or alarm, such as: • IF SYNTHESIZER • DATA CLOCK SYN • I CHANNEL •...
  • Page 115 SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT:STORED FLTS/ALMS:TX INTERFACE TX INTERFACE STORED TIME/DATE Displays the stored date and time of a fault or alarm, such as: • TX DROP • TX DATA/AIS • TX CLK PLL •...
  • Page 116 SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: STORED FLTS/ALMS: COMMON COMMON STORED TIME/DATE Displays the stored date and time of a fault or alarm, such as: • BATTERY/CLOCK • -12 VOLT SUPPLY • +12 VOLT SUPPLY •...
  • Page 117 SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: STORED FLTS/ALMS: UNAVAILABLE SECONDS (CONDITIONAL) UNAVAL SECONDS STORED TIME/DATE Conditional: This is available only with the Reed-Solomon option. IMPORTANT A fault is indicated if the Reed-Solomon Codec could not correct bit errors in one block of serialized data in any given second.

  • Page 118: Function Select: Remote Aupc (Conditional)

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM 4.3.5 FUNCTION SELECT: REMOTE AUPC (CONDITIONAL) FUNCTION SELECT REMOTE AUPC Conditional: This menu is available when AUPC selection is made from the Modem Type menu, located under the Utility: Modem Type menu.
  • Page 119 SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: REMOTE AUPC: CONFIGURATION: AUPC ENABLE (CONDITIONAL) AUPC ENABLE Conditional: This menu is available the AUPC selection is made from the Modem Type menu, located under the Utility: Modem Type menu.

  • Page 120: Tx 2047 Pattern

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: REMOTE AUPC: CONFIGURATION: TX 2047 PATTERN (CONDITIONAL) TX 2047 PATTERN Conditional: This menu is available when AUPC selection is made from the Modem Type menu, located under the Utility: Modem Type menu.

  • Page 121: Function Select Utility

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: REMOTE AUPC: CONFIGURATION: REMOTE AUPC: MONITOR: 2047 ERRORS (CONDITIONAL) 2047 ERRORS n.n E-e Conditional: This menu is available when AUPC selection is made from the Modem Type menu, located under the Utility: Modem Type menu.

  • Page 122: Function Select: Utility: Modulator

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM 4.3.6.1 FUNCTION SELECT: UTLITY: FIXED MODEM RATE UTILITY FIXED MODEM RATE FUNCTION SELECT: UTLITY: FIXED MODEM RATE: CODE RATE/DATA RATE (CONDITIONAL) CR: _____________ DR: ___________Kb This menu is displayed when the modem has the Single Data Rate option and the code/data rates are not programmed.
  • Page 123 SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: UTLITY: MODULATOR: ASSIGN TRANSMIT FILTERS Note: Alternating the setting in the following menus, changes the settings in the menus that appear under the Configuration: Modulator menus. TX-A QPSK 1/2 64.000 Kbps...
  • Page 124 SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM Select one of four (A, B, C, or D) pre-defined transmitter code/data rate combinations or a variable rate selection (V). Continuous Mode Data Rate Code Rate Data Rate Range Non-Turbo Requirements BPSK 1/2 2.4 to 1250 kbps...
  • Page 125 SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: UTILITY: MODULATOR: TX TERMINAL LO TX TERMINAL LO 0 MHz MIX:- Valid selections entered into this menu make it possible to directly program the frequency transmitted from the satellite terminal using the Configuration: Modulator: Terminal Frequency menu.

  • Page 126: Mod Power Offset

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: UTILITY: MODULATOR: MOD POWER OFFSET MOD POWER OFFSET + 0.0 dB Modulator power offset adjusts. Offsets the modulator output power readout in the Configuration menu. This feature does not actually change the modulator power level, but displays an offset value in the monitor.

  • Page 127: Tx Bpsk Ordering

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: UTILITY: MODULATOR: SCRAMBLER TYPE SCRAMBLER TYPE INTELSAT V.35 This menu is status only and displays: • With RS Scrambler On: EFD MOD V.35 or IBS SYNC • With Turbo Scrambler On: TURBO SYNC Intelsat V.35, FDC MOD V.35, ITU V.35, or Off.

  • Page 128: Tx-Rs N/K Deep

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: UTILITY: MODULATOR: TX-RS N/K DEEP (CONDITIONAL) TX-RS N/K DEEP 225/205 Conditional: This menu is active when Reed-Solomon (RS) is installed and RS is On (under Configuration: Modulator). IMPORTANT N/K is status only.

  • Page 129: Rf Mode Control

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: UTILITY: MODULATOR: ODU ALARM - LOW ODU ALARM - LOW 0 MA Sets ODU Alarm – Low within 0 to 4000 mA, in 1 mA steps. An alarm is produced whenever the ODU or BUC current falls below the programmed limit.

  • Page 130: Function Select: Utility: Modulator: Tx Symbol Rate

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM This command allows for enabling or disabling of the TX carrier output depending on the described conditions. One application for command is the operation of demand network systems. FUNCTION SELECT: UTILITY: MODULATOR: TX SYMBOL RATE TX SYMBOL RATE 64.000 Ksps...
  • Page 131 SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT:UTILITY:DEMODULATOR: ASSIGN RECEIVE FILTERS Note: Alternating the setting in the following menus, changes the settings in the menus that appear under the Configuration: Demodulator menus. RX-A QPSK 1/2 64.000 Kbps...
  • Page 132 SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM Select one of four (A, B, C, or D) pre-defined receiver code/data rate combinations or a variable rate selection (V). Continuous Mode Data Rate Code Rate Data Rate Range Non-Turbo Requirements BPSK 1/2 2.4 to 1250 kbps...

  • Page 133: Function Select:utility: Demodulator: Rx Terminal Lo

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT:UTILITY: DEMODULATOR: RX TERMINAL LO RX TERMINAL LO O MHz MIX: - Valid selections entered into this menu make it possible to directly program the frequency received by the satellite terminal using the Configuration: Demodulator: Terminal Frequency menu.

  • Page 134: Demodulator Type

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: UTILITY: DEMODULATOR: DEMODULATOR TYPE (CONDITIONAL) DEMODULATOR TYPE INTELSAT OPEN Conditional: RX FILTER TYPE is selectable only when Custom is selected for modem type in the Utility: Modem Type menu.

  • Page 135: Descrambler Type

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: UTILITY: DEMODULATOR: DESCRAMBLER TYPE DESCRAMBLER TYPE INTELSAT V.35 This menu is status only and displays: • With RS Descrambler On: EFD MOD V.35 or IBS SYNC • With Turbo Descrambler On: TURBO SYNC Intelsat V.35, FDC MOD V.35, ITU V.35, or Off.

  • Page 136: Max Packet Size

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: UTILITY: DEMODULATOR: MAX PACKET SIZE MAX PACKET SIZE 2048 BITS Maximum Packet Size: 0 to 1048567 bits. FUNCTION SELECT: UTILITY: DEMODULATOR: DEMOD SPECTRUM DEMOD SPECTRUM NORMAL Programmable vector rotation. Select Normal or Inverted for spectrum reversal of the I and Q baseband channels.
  • Page 137 SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: UTILITY: DEMODULATOR: RX IESS-310 MODE (CONDITIONAL) RX IESS-310 MODE Conditional: Note: Only available when the 8-PSK option is selected and Reed-Solomon option is installed and selected. IMPORTANT Selection of On or Off used for 8-PSK 2/3 with Reed-Solomon.

  • Page 138: Rx Symbol Rate

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: UTILITY: DEMODULATOR: RX SYMBOL RATE RX SYMBOL RATE 64.000 Ksps Status Only. Programmable with 4.800 to 2500 ksps. Provides the symbol rate corresponding to the data rate, code rate(s), modulation, and overhead (framing) programmed into the demodulator.

  • Page 139: Function Select: Utility: Interface: Buffer Program

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: UTILITY: INTERFACE: BUFFER PROGRAM BUFFER PROGRAM BITS Allows selection of either Bits or Milliseconds for the receive buffer. • For the modem to calculate buffer size, select Milliseconds. •...

  • Page 140: Function Select: Utility: Interface: Rx Data Phase

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: UTILITY: INTERFACE: RX DATA PHASE RX DATA PHASE NORMAL RX data phase relationship. Use this option to select Normal or Invert for the RX data relationship to the selected RX clock.

  • Page 141: Function Select: Utility: Outdoor Unit: Odu Fsk Address (Conditional)

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: UTILITY: OUTDOOR UNIT: ODU FSK ADDRESS (CONDITIONAL) ODU FSK ADDRESS Conditional: This menu is available only when ODU Power Supply, FSK, and TX-IF Output are On. IMPORTANT Selects the address the modem will use to communicate with an FSK capable ODU. Address shall be within 1 to 15.

  • Page 142: Odu Pwr Leveling

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: UTILITY: OUTDOOR UNIT: ODU PWR LEVELING (CONDITIONAL) ODU PWR LEVELING Conditional: This menu is available only when ODU Power Supply, and TX-IF Output are On. IMPORTANT When Power Leveling is On the Modem TX-IF Output is continually adjusted to maintain the ODU Power level set by selecting ODU PWR Leveling = On.

  • Page 143: Function Select: Utility: System: Remote Baud Rate

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: UTILITY: SYSTEM: REMOTE BAUD RATE REMOTE BAUD RATE 9600 bps EVEN The parity and baud rate settings of the modem are displayed. To change the modem baud rate and/or parity, press <ENTER>. Press [←] or [→] to position the cursor over the parameter to be changed.

  • Page 144: Function Select: Utility: System: Operation Mode

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: UTILITY: SYSTEM: OPERATION MODE OPERATION MODE DUPLEX Programs the modem for DUPLEX, TX ONLY, or RX ONLY operation. Note: When TX ONLY or RX ONLY is selected, the appropriate faults are masked from the Faults and Stored Faults menus.

  • Page 145: Function Select: Utility: System: Lamp Test

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: UTILITY: SYSTEM: LAMP TEST LAMP TEST ?? PRESS ENTER Lamp test function. Press <ENTER> to turn the front panel indicators on for 3 seconds. FUNCTION SELECT: UTILITY: SYSTEM: SELF TEST SELF TEST Select OFF, AUTO, or RUN.

  • Page 146: Function Select: Utility: System: M&C Firmware

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: UTILITY: SYSTEM: M&C FIRMWARE M&C FIRMWARE FW/NNNNNN-DDR Displays the M&C module firmware version. M&C FIRMWARE MM/DD/YYYY Press <ENTER> to display the month, day, and year. FUNCTION SELECT: UTILITY: SYSTEM: BOOT FIRMWARE...

  • Page 147: Function Select: Utility: System: Fpga Firmware

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: UTILITY: SYSTEM: FPGA FIRMWARE FPGA FIRMWARE FW/NNNNNN-DDR Displays the FPGA module firmware version. FPGA FIRMWARE MM/DD/YYYY Press <ENTER> to display includes the month, day, and year. TURBO FIRMWARE FW/NNNNR Note: This menu is displayed only when the Turbo option is installed.

  • Page 148: Ext Agc: Min Pwr

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: UTILITY: SYSTEM: EXT AGC: MIN POWER EXT AGC: MIN PWR 10.0 Volts Sets the AGC voltage for a RX signal. The voltage range is 0.0 to 10.0V, in 0.5V steps. Upon entry, the current external AGC voltage level is displayed.

  • Page 149: Modem Type

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM 4.3.6.7 FUNCTION SELECT: UTILITY: MODEM TYPE UTILITY MODEM TYPE Select information to view using the [←] [→] arrow keys, then press <ENTER>. FUNCTION SELECT: UTILITY: MODEM TYPE: MODEM TYPE MODEM TYPE CUSTOM Several selections from this menu require optional hardware and software.
  • Page 150 SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: UTILITY: MODEM TYPE: MODEM OPTIONS MODEM OPTIONS -+ + - + - - - + + + + + - - + Status Only. Displays the installed modem options.

  • Page 151: Card #2 Type

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: UTILITY: MODEM TYPE: CARD #1 TYPE CARD #1 TYPE NOT INSTALLED Status Only. Not Installed FUNCTION SELECT: UTILITY: MODEM TYPE: CARD #2 TYPE CARD #2 TYPE REED SOLOMON 03 Status Only.

  • Page 152: Card #1 Options

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: UTILITY: MODEM TYPE: CARD #1 OPTIONS (CONDITIONAL) CARD #1 OPTIONS ----- Status Only. Menu appears when Card #1 is installed. FUNCTION SELECT: UTILITY: MODEM TYPE: CARD #2 OPTIONS (CONDITIONAL) CARD #2 OPTIONS Status Only.

  • Page 153: Card #3 Options

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: UTILITY: MODEM TYPE: CARD #3 OPTIONS (CONDITIONAL) CARD #3 OPTIONS (Status Only.) Menu appears when Card #3 is installed. Displays one of the following: REED SOLOMON 02 LIST: INTELSAT...

  • Page 154: Modem Serial

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM FUNCTION SELECT: UTILITY: MODEM TYPE: MODEM SERIAL # MODEM SERIAL # 012345678 Status Only. Displays the modem serial number. FUNCTION SELECT: UTILITY: MODEM TYPE: CARD #1 SERIAL # CARD #1 SERIAL # 012345678 Status Only.

  • Page 155: Card #3 Serial

    ] to increment or decrement ← → ↑ ↓ the digit at the flashing cursor. Press <ENTER> to execute the change. Entering this code enables the corresponding modem option. To purchase an option, contact an Comtech EF Data marketing representative for more information. 4–91...
  • Page 156 ] to increment or decrement ← → ↑ ↓ the digit at the flashing cursor. Press <ENTER> to execute the change. Entering this code enables the corresponding modem option. To purchase an option, contact an Comtech EF Data marketing representative for more information. 4–92...
  • Page 157 ] to increment or decrement ← → ↑ ↓ the digit at the flashing cursor. Press <ENTER> to execute the change. Entering this code enables the corresponding modem option. To purchase an option, contact an Comtech EF Data marketing representative for more information 4–93...

  • Page 158: Function Select: Utility: Factory Set-Up

    Press <ENTER> to execute the change. Entering this code enables the corresponding modem option. To purchase an option, contact an Comtech EF Data marketing representative for more information. 4.3.6.8 FUNCTION SELECT: UTILITY: FACTORY SET-UP...

  • Page 159: Custom Modem Defaults

    SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM Custom Modem Defaults Refer to Table 4-2 for custom modem defaults. Note: The following parameter do not revert to default settings after a hard reset: • • Address/Parity/Baud Rate EXT AGC Max Power •...
  • Page 160 SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM Table 4-2. Custom Modem Defaults (Continued) Function Select Monitor RAW BER 2.4 E-3 ODU Voltage 0 mA Corrected BER 4.0 E-3 ODU Output Level xx.xx dBm E b /N 0 16.0 dB ODU Output Level xx.xx/xx.xxT dBm...
  • Page 161 SNM-1001L Satellite Modem Revision 1 Front Panel Operation MN/SNM1001L.IOM Table 4-2. Custom Modem Defaults (Continued) Utility Interface TX Overhead Type None RTS TX-IF CNTRL RX Overhead Type None TX Data Phase Normal Buffer Program Bits RX Data Phase Normal CTS Delay...
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  • Page 163: Chapter 5. Modem Type

    Chapter 5. MODEM TYPE This section provides additional detail about the Modem Type setting located under the Function Select: Utility: Modem Type menu. Modem Type This section provides additional detail information about the Modem Type setting located under the Utility: Modem Type menu. Refer to Table 5-1 for configuring the modem to the following types of operation.

  • Page 164: Aupc Operation (With Reed-Solomon)

    5.1.2 Closed Network Operation (Comtech EF Data) The modem does not require any additional hardware installed to operate in Comtech EF Data Closed Network configuration. The basic modem configuration, which includes the 25-pin D Data I/O connector, supports V.35, EIA-422, and EIA-232 data with no overhead. The Comteech EF Data closed network configuration allows the modem to be compatible with any Comtech EF Data closed network application.

  • Page 165: Custom Operation

    TX Clock Source TX Terrestrial Configuration: Interface Buffer Clock Source Satellite Clock Configuration: Interface Modulator Type Comtech EF Data Closed (All Utility: Modulator modulator types are accessible) Encoder Type Viterbi or Sequential Utility : Modulator Demodulator type Comtech EF Data Closed (All...

  • Page 166: Reed-Solomon Modes

    SNM-1001L Satellite Modem Revision 1 Modem Types MN/SNM1001L.IOM Reed-Solomon Modes Reed-Solomon polynomial is compatible with Intelsat (IESS-308, IESS-309, IESS-310, and IESS-314). Table 5-3 shows the Reed-Solomon parameter used for various configurations. Table 5-3. Reed-Solomon Modes Modem Menu Description Configuration Modulator TX...

  • Page 167: Clocking Options

    Chapter 6. CLOCKING AND RX BUFFERING SETTINGS Clocking Options Clocking of the data from the terrestrial equipment to the satellite (and vice versa) will depend on the application. This section describes the most common options and recommended configurations. 6.1.1 EIA-232, EIA-422, or V.35 Master/Master Refer to Figure 6-1 for: •...

  • Page 168: Buffering

    SNM-1001L Satellite Modem Revision 1 Clocking Options MN/SNM1001L.IOM The use of loop timing in the modem is an option for both EIA-422 and V.35 operation. SCT (LOOP): SCT (INTERNAL) clock no longer applies when the modem has loop timing on. The TX clock source is now recovered from the RX satellite data. This recovered clock is put out on the ST line and is used to clock the terrestrial equipment.

  • Page 169: Figure 6-1. Eia-422, Eia-232, Or V.35 Master/Master Clocking Diagram

    SNM-1001L Satellite Modem Revision 1 Clocking Options MN/SNM1001L.IOM TXCLOCK = TX TERRESTRIAL HIGH STABILITY OSCILLATOR INTERNAL OSCILLATOR TRANSMIT RECEIVE EXT REF TERRESTRIAL SATELLITE DATA CLOCK BUFFER RECOVERY CLOCK BUFFER CLOCK = TX TERRESTRIAL MASTER BUFFER CLOCK = TX TERRESTRIAL CLOCK...

  • Page 170: Figure 6-2. Eia-422, Eia-232, Or V.35 Master/Slave Clocking Diagram

    SNM-1001L Satellite Modem Revision 1 Clocking Options MN/SNM1001L.IOM TXCLOCK = TX TERRESTRIAL HIGH STABILITY OSCILLATION TERRESTRIAL INTERNAL OSCILLATOR TRANSMIT RECEIVE EXT REF SATELLITE DATA CLOCK BUFFER RECOVERY CLOCK BUFFER CLOCK = TX TERRESTRIAL MASTER BUFFER CLOCK = RX (SATELLITE CLOCK)
  • Page 171 SNM-1001L Satellite Modem Revision 1 Clocking Options MN/SNM1001L.IOM PLESIOCHRONOUS OPERATION IS NOT EXACTLY EQUAL TO f 1) INCOMING TRAFFIC TOO FAST 2) INCOMING TRAFFIC TOO SLOW BIT 1 BIT 1 BIT 1 BIT 1 ERROR ERROR BIT 2 BIT 2...

  • Page 172: Figure 6-4. Doppler Shift

    SNM-1001L Satellite Modem Revision 1 Clocking Options MN/SNM1001L.IOM SATELLITE MOTION AND ORBITAL INCLINATION A SATELLITE IS MAINTAINED AT AN ASSIGNED GEOSTATIONARY GEO-SYNCHRONOUS LOCATION THROUGH THE USE OF INCLINED ORBIT GROUND COMMAND ADJUSTMENTS TO ITS N/S AND E/W LOCATION. THIS SATELLITE...

  • Page 173: Doppler

    SNM-1001L Satellite Modem Revision 1 Clocking Options MN/SNM1001L.IOM Doppler A geostationary satellite should be positioned directly over the equator and orbit with a duration of 24 hours. In practice, the exact inclination of the satellite (relative to the equator) is influenced by the earth, moon, and sun’s gravity, as well as solar wind.

  • Page 174: Plesiochronous

    SNM-1001L Satellite Modem Revision 1 Clocking Options MN/SNM1001L.IOM Plesiochronous The stability of station reference clocks is normally 1 x 10 (derived from a cesium standard). While the stability is exceptionally high, the two clocks are not in synchronization with each other and will eventually pass by each other.

  • Page 175: Frame/Multiframe Length

    SNM-1001L Satellite Modem Revision 1 Clocking Options MN/SNM1001L.IOM Frame/Multiframe Length The depth of the receive buffer required is applicable to all unframed data. When the data is framed (such as 2048 kbps G732 or 1544 kbps G733), it is desirable to provide slips in predefined locations.
  • Page 176 SNM-1001L Satellite Modem Revision 1 Clocking Options MN/SNM1001L.IOM This page is intentionally left blank. 6–10...

  • Page 177: Introduction

    Closed Network compatible with the vast majority of existing modems. The SNM-1001L can be fitted with a Turbo Product Codec. Turbo Product Coding is small SIMM module that can be fitted to the unit at time of manufacturing.

  • Page 178: Coding

    7.3.1 Introduction Comtech EF Data implements the FEC Codec based on TPC. A Turbo Product Code is a two dimensional array of block codes. Encoding is relatively straightforward, but decoding is a very complex process requiring multiple iterations of processing for maximum performance to be achieved.

  • Page 179: Mod/Demod Processing Delay

    SNM-1001L Satellite Modem Revision 1 Forward Error Correction Options MN/SNM1001L.IOM 7.3.2 Mod/Demod Processing Delay In many cases, FEC methods that provide increased coding gain do so at the expense of increased processing delay. However, with TPC, this increase in delay is very modest.

  • Page 180: Uncoded Operation (No Fec)

    529 kHz The occupied bandwidth is defined at the width of the transmitted spectrum taken at the -10 dB points on the plot of power spectral density. This equates to 1.19 x symbol rate for the SNM-1001L transmit filtering. Included for comparative purposes.
  • Page 181 There are occasions where a user may wish to operate a satellite link with no forward error correction of any kind. For this reason, the SNM-1001L offers this uncoded mode for three modulation types - BPSK, QPSK and Offset QPSK. However, the user should be aware of some of the implications of using this approach.
  • Page 182 The problem becomes progressively better with increasing symbol rate. Comtech EF Data is not responsible for incorrect operation if the user does not adhere to these guidelines when using uncoded operation.

  • Page 183: Figure 7-1. Viterbi Decoder

    SNM-1001L Satellite Modem Revision 1 Forward Error Correction Options MN/SNM1001L.IOM BPSK/OQPSK Viterbi Decoding 1.0E-02 1.0E-03 Specification Limit Rate 3/4 Coding 1.0E-04 Specification Limit Rate 1/2 Coding 1.0E-05 Specification Limit Rate 7/8 Coding 1.0E-06 Specification Limit 8PSK Rate 2/3 Coding 1.0E-07 1.0E-08...

  • Page 184: Figure 7-2. Viterbi Decoder And Reed-Solomon

    SNM-1001L Satellite Modem Revision 1 Forward Error Correction Options MN/SNM1001L.IOM BPSK/OQPSK, Viterbi Decoder, Reed Solomon 1.0E-05 1.0E-06 1.0E-07 Specification Limit Rate 8PSK 2/3 1.0E-08 Specification Limit Rate 3/4 Coding Specification Limit 1.0E-09 Rate 7/8 Coding Specification Limit Rate 1/2 Coding 1.0E-10...

  • Page 185: Figure 7-3. Bpsk And {O}Qpsk Ber Performance

    SNM-1001L Satellite Modem Revision 1 Forward Error Correction Options MN/SNM1001L.IOM UNCODED 1:1 BPSK OQPSK 1.0E-02 1.0E-03 Specification Limit Rate Uncoded 1:1 1.0E-04 1.0E-05 1.0E-06 1.0E-07 10.0 11.0 12.0 Eb/No (dB) Figure 7-3. BPSK and {O}QPSK BER Performance 7–9...

  • Page 186: Figure 7-4. Turbo Product Codec

    SNM-1001L Satellite Modem Revision 1 Forward Error Correction Options MN/SNM1001L.IOM BPSK/QPSK/8PSK Turbo Product Codec 1.0E-05 1.0E-06 Specification Limit QPSK Rate 1/2 Coding Specification Limit 1.0E-07 8PSK Rate 3/4 Coding 1.0E-08 Specification Limit QPSK Rate 3/4 Coding 1.0E-09 Specification Limit BPSK Rate 21/44 Note: BPSK 5/16 is 1.0E-09 at 4.0...

  • Page 187: Figure 7-5. Sequential Decoder, Reed-Solomon, And 1544 Kbps

    SNM-1001L Satellite Modem Revision 1 Forward Error Correction Options MN/SNM1001L.IOM Sequential Decoder, Reed-Solomon 1544 Kbps 1.0E-05 1.0E-06 Specification Limit Rate 3/4 Coding 1.0E-07 Specification Limit Specification Limit Rate 1/2 Coding Rate 7/8 Coding 1.0E-08 1.0E-09 1.0E-10 1.0E-11 10.0 11.0 12.0 Eb/No (dB) Figure 7-5.

  • Page 188: Figure 7-6. Sequential Decoder And 56 Kbps

    SNM-1001L Satellite Modem Revision 1 Forward Error Correction Options MN/SNM1001L.IOM BPSK/OQPSK Sequential Decoder 56 Kbps 1.0E-02 1.0E-03 Specification Limit Rate 7/8 Coding 1.0E-04 Specification Limit 1.0E-05 Specification Limit Rate 1/2 Coding 1.0E-06 1.0E-07 1.0E-08 1.0E-09 10.0 11.0 12.0 Eb/No (dB) Figure 7-6.

  • Page 189: Figure 7-7. Sequential Decoder And 1544 Kbps

    SNM-1001L Satellite Modem Revision 1 Forward Error Correction Options MN/SNM1001L.IOM BPSK/QPSK Sequential Decoder 1544 Kbps 1.0E-02 Specification Limit Rate 7/8 Coding 1.0E-03 Specification Limit 1.0E-04 Rate 3/4 Coding 1.0E-05 Specification Limit Rate 1/2 Coding 1.0E-06 1.0E-07 1.0E-08 1.0E-09 10.0 11.0 12.0...
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  • Page 191: Chapter 8. System Checkout

    Chapter 8. SYSTEM CHECKOUT System Checkout This equipment contains parts and assemblies sensitive to damage by ESD. Use ESD precautionary procedures when touching, removing, or inserting PCBs. CAUTION The modem comes equipped with an internal self-test feature. This feature is designed to provide the operator with maximum confidence that the modem is operational without installing external equipment.

  • Page 192: 8.1.1 Interface Checkout

    SNM-1001L Satellite Modem Revision 1 System Checkout MN/SNM1001L.IOM 8.1.1 Interface Checkout Use the following procedure and the test setup in Figure 5-1to inspect the interface. Figure 8-1. Fault Isolation Test Setup 1. Connect a BER test set to the appropriate modem data connector.

  • Page 193: Modulator Checkout

    SNM-1001L Satellite Modem Revision 1 System Checkout MN/SNM1001L.IOM 8.1.2 Modulator Checkout Use the following procedure to check out the modulator: 1. Set up the equipment as shown in Figure 8-1. 2. Set up the modem for operation by using the Configuration Modulator and Demodulator front panel menus.

  • Page 194: Table 8-1. Conversion To S/N And Eb/N0 Chart

    SNM-1001L Satellite Modem Revision 1 System Checkout MN/SNM1001L.IOM Table 8-1. Conversion to S/N and Eb/N0 Chart (dB) Code Rate 1/2 Code Rate 3/4 Code Rate 7/8 (S+N)/N E b /N 0 E b /N 0 E b /N 0 -0.6 10.0...

  • Page 195: Demodulator Checkout

    SNM-1001L Satellite Modem Revision 1 System Checkout MN/SNM1001L.IOM Figure 8-2. Typical Output Spectrum 8.1.3 Demodulator Checkout Use the following procedure to test the demodulator. 1. Set up the equipment. 2. Set up the modem with an external IF loop and level. Use a properly operating modulator, and ensure that power levels, data rates, code rates, etc., are...

  • Page 196: Figure 8-3. Typical Eye Constellations

    SNM-1001L Satellite Modem Revision 1 System Checkout MN/SNM1001L.IOM WITH NOISE WITHOUT NOISE Figure 8-3. Typical Eye Constellations 8–6...

  • Page 197: Chapter 9. Fault Isolation

    Note: Each fault or alarm category includes possible problems and the appropriate action required to repair the modem. If any of the troubleshooting procedures mentioned earlier in this chapter do not isolate the problem, and Comtech EF Data Customer Support assistance is necessary, have the following information available for the representative: •...

  • Page 198: System Faults/Alarms

    SNM-1001L Satellite Modem Revision 1 Fault Isolation MN/SNM1001L.IOM 9.1.1 System Faults/Alarms System faults are reported in the “Faults/Alarms ” menu, and stored faults are reported in the “Stored Flts/Alms” menu. 9.1.2 Faults/Alarms Display General fault, status, and alarm information are indicated by 10 LEDs located on the modem’s front panel.
  • Page 199 DATA CLOCK SYN I CHANNEL Q CHANNEL MODEM REF ACT MODULE CONFIGURATION MODEM REF PLL CARRIER DETECT IF SYNTHESIZER I CHANNEL Q CHANNEL BER THRESHOLD MODULE CONFIGURATION LNB CURRENT CURRENT VOLTAGE TEMPERATURE PLL LOCK CHECKSUM Figure 9-1. SNM-1001L Fault Tree 9–3...
  • Page 200 IBS only. D&I only. **** A connection between the common and N.C. contacts indicate fault. ***** Signal is open collector high impedance if faulted. A connection between the common and N.O. contacts indicate alarm. Figure 9-1. SNM-1001L Fault Tree (Continued) 9–4...

  • Page 201: Modulator Faults

    SNM-1001L Satellite Modem Revision 1 Fault Isolation MN/SNM1001L.IOM 9.1.3.2 Modulator Faults Fault/Alarm Possible Problem and Action IF SYNTHESIZER Modulator IF synthesizer fault. This is considered a major alarm, and will turn off the modulator output. Return the modem for repair.

  • Page 202: Demodulator Faults

    SNM-1001L Satellite Modem Revision 1 Fault Isolation MN/SNM1001L.IOM 9.1.3.3 Demodulator Faults Fault/Alarm Possible Problem and Action CARRIER DETECT Carrier detect fault. Indicates the decoder is not locked. This is the most common fault displayed in the modem. Any problem from the input data on the modulator end of the circuit to the output of the decoder can cause this alarm.

  • Page 203: Common Equipment Faults

    TEMPERATURE ODU Temperature fault. PLL LOCK PLL Lock fault. Indicates the PLL is not locked to the reference of the interface transmit clock recovery oscillator. Contact the Comtech EF Data Customer Support Department. CHECKSUM Checksum fault. 9.1.3.5 Common Equipment Faults...
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  • Page 205: Chapter 10. Automatic Uplink Power Control

    Chapter 10. AUTOMATIC UPLINK POWER CONTROL 10.1 AUPC Note: If required install the Reed-Solomon card. The AUPC channel is MUXed onto the data and transmitted at an overhead rate of 16/15 of the main channel. The AUPC feature allows remote communication between a local modem and a remote modem.

  • Page 206: Figure 10-1. Aupc Block Diagram

    SNM-1001L Satellite Modem Revision 1 Automatic Uplink Power Control MN/SNM1001L.IOM AUPC DATA F R O M M & C T E R R D A T A I N P U T EIA-422 F I F O T E R R C L O C K TERR D A T A V .

  • Page 207: Modes Of Aupc Location

    SNM-1001L Satellite Modem Revision 1 Automatic Uplink Power Control MN/SNM1001L.IOM 10.2 Modes of AUPC Location There are two modes of AUPC location: AUPC between two modems Maintains a target Eb/No programmed into the modem at each end. Self-Monitoring AUPC with...

  • Page 208: Aupc - Between Two Modems

    SNM-1001L Satellite Modem Revision 1 Automatic Uplink Power Control MN/SNM1001L.IOM With Local AUPC On, set modems (A and B), if modem A loses carrier: 1. Modem A sets its output power (MAXIMUM, MINIMUM, OR HOLD) as specified by LOCAL CL ACTION.

  • Page 209: Self-Monitoring Local Modem Aupc Control

    SNM-1001L Satellite Modem Revision 1 Automatic Uplink Power Control MN/SNM1001L.IOM 10.2.1.1 Remote AUPC This feature allows the user to monitor and control a remote modem location using the front panel or serial port of the local modem. The operator can set or reset the following commands: •...

  • Page 210: Mux Operation

    SNM-1001L Satellite Modem Revision 1 Automatic Uplink Power Control MN/SNM1001L.IOM 10.2.3 MUX Operation The MUX receives terrestrial and AUPC data from the selected receivers. The terrestrial data flows into a small First In/First Out (FIFO) buffer. The FIFO buffer aids in the rate exchange between the terrestrial data rate and the overhead rate.

  • Page 211: Loop Timing Operation

    SNM-1001L Satellite Modem Revision 1 Automatic Uplink Power Control MN/SNM1001L.IOM Based on this selection, terrestrial data is clocked out of the buffer to the selected drivers and on to the end user. 10.2.6 Loop Timing Operation The appropriate RX buffer clock choice for loop timing is RX Satellite. This will clock out the data from the modem using the recovered clock from the demodulator IF input.

  • Page 212: Aupc Modem Defaults

    SNM-1001L Satellite Modem Revision 1 Automatic Uplink Power Control MN/SNM1001L.IOM 10.2.8.1 AUPC Modem Defaults Modulator Demodulator Data Rate Data Rate TX Rate A 64 kbps, QPSK 1/2 RX Rate A 64 kbps, QPSK 1/2 TX Rate B 256 kbps, QPSK 1/2...

  • Page 213: Chapter 11. Asymmetrical Loop Timing

    Chapter 11. ASYMMETRICAL LOOP TIMING 11.1 Asymmetrical Loop Timing Asymmetrical Loop Timing is the same timing method that is designed into the SDM-650B TROJAN interfaces. Refer to Figure 11-1 and Figure 11-2 for TX and RX Asymmetrical Loop Timing block diagram. There are two advantages for using Asymmetrical Loop Timing: •...

  • Page 214: Figure 11-1. Transmit Section Of The Asymmetrical Loop Timing Block Diagram

    SNM-1001L Satellite Modem Revision 1 Asymmetrical Loop Timing MN/SNM1001L.IOM The transmit data is normally clocked into the modem with the Terminal Timing (TT) clock in typical EIA-422 operation. The received data is clocked out with the Receive Timing (RT) clock. The asymmetrical loop timing option allows the transmit and receive data to be clocked with the same, or a multiple of the same clock.

  • Page 215: Figure 11-2. Receive Section Of The Asymmetrical Loop Timing Block Diagram

    SNM-1001L Satellite Modem Revision 1 Asymmetrical Loop Timing MN/SNM1001L.IOM TERR Note: PLL will be bypassed when the RX data rate is set to the TX data rate. This will disable the Asymmetrical Mode. Figure 11-2. Receive Section of the Asymmetrical Loop Timing Block Diagram...
  • Page 216 SNM-1001L Satellite Modem Revision 1 Asymmetrical Loop Timing MN/SNM1001L.IOM Example: Master/Slave Clocking Setup: 1. Master site has a 10 MHz clock that is needed as the clock source. 2. Unequal data rates: 4.096 Mbps and 2.152 Mbps (numbers divisible by 8).

  • Page 217: Chapter 12. Fully Accesible System Topology (Fast)

    The access code can be purchased at any time from Comtech EF Data. Once obtained, the access code is loaded into the unit through the front panel keyboard or the rear remote port.

  • Page 218: Activation Procedure

    SNM-1001L Satellite Modem Revision 1 Fully Accessible System Topology (FAST) MN/SNM1001L.IOM 12.1.1.1 Activation Procedure Obtain Modem Serial Number 1. Press [CLEAR] to return to the Main menu. 2. Use [←] and [→] to select Function Select menu. 3. Press [ENTER].
  • Page 219 8. Record Card #2 serial number, if displayed: 9. Press [CLEAR]. 10. Contact a Comtech EF Data sales representative to order features. 11. Comtech EF Data Customer Support personnel will verify the order and provide an invoice and instructions. Entering Access Codes from the Front Panel 1.
  • Page 220 “+” sign. If a “+” sign is evident, the upgrade is completed. If upgrade is incorrect, the menu display will exhibit “WRONG CODE ENTERED.” Repeat procedures. Contact Comtech EF Data Customer Support personnel for further instructions, if the error message remains.

  • Page 221: Variable Data Rates

    SNM-1001L Satellite Modem Revision 1 Fully Accessible System Topology (FAST) MN/SNM1001L.IOM 12.2 Variable Data Rates The basic platform modem comes with single data rate capabilities. At the time of purchase, the customer may add optional variable data rate capabilities. If variable rate requirements arise after the purchase of a basic platform modem, these capabilities can be added in the field using FAST technology.
  • Page 222 SNM-1001L Satellite Modem Revision 1 Fully Accessible System Topology (FAST) MN/SNM1001L.IOM This page is intentionally left blank. 12–6...

  • Page 223: Chapter 13. Buc Fsk Communications

    Chapter 13. BUC FSK COMMUNICATIONS 13.1 Introduction The modulator includes capability to communicate with an ODU Block Up Converter (BUC) using an FSK signal multiplexed onto the IF output connector along with the TX IF signal, 10 MHX reference, and DC power to the BUC. The M&C implements commands to control BUC functions and to query the BUC for configuration or status information.

  • Page 224: Transmission Interface

    SNM-1001L Satellite Modem Revision 1 BUC FSK Communications MN/SNM1001L.IOM On power-up, the TX carrier is Off until the BUC is commanded to turn the carrier on (unless the unit is commanded into the power On mode at the factory). The BUC does not allow the carrier to be turned On unless the PLL is locked, and automatically turns the carrier Off in the event the PLL goes out-of-lock.

  • Page 225: Response Message Structure (Buc To Idu)

    SNM-1001L Satellite Modem Revision 1 BUC FSK Communications MN/SNM1001L.IOM 13.2.2 Response Message Structure (BUC to IDU) Byte Name Description Value Address Address of BUC shifted left by 4 0x10 to 0xf0 Level Byte 1 MSbyte of TX output power Level Byte 2...
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  • Page 227: Chapter 14. Decoder

    Chapter 14. DECODER 14.1 Decoder 14.1.1 Sequential Decoder The sequential decoder is used in closed network applications, typically in Frequency Division Multiple Access (FDMA) satellite communications systems. The sequential decoder is a FAST option. Refer to Figure 14-1 for a block diagram of the sequential decoder. MICRO- MICROCOMPUTER COMPUTER...
  • Page 228 SNM-1001L Satellite Modem Revision 1 Decoder MN/SNM1001L.IOM 14.1.1.1 Theory of Operation The sequential decoder also works in conjunction with the convolutional encoder at the transmitting modem to correct bit errors in the received data stream from the demodulator. The sequential decoder processes 2-bit quantized I&Q channel data symbols from the demodulator.

  • Page 229: Viterbi Decoder

    SNM-1001L Satellite Modem Revision 1 Decoder MN/SNM1001L.IOM The sequential decoder also provides a lock detect signal to the M&C when the error rate has dropped below a threshold level. The M&C monitors these signals and takes appropriate action. The raw BER count is made by comparing the input and output decoder data. Because the output data contains many fewer errors than the input, differences in the two can be counted to yield the raw BER.
  • Page 230 SNM-1001L Satellite Modem Revision 1 Decoder MN/SNM1001L.IOM 14.1.2.1 Viterbi Specification Parameter Specification See Chapter 1 Maximum Data Rate 2.048 Mbps (rate 1/2) 2.048 Mbps (rate 3/4) 2.048 Mbps (rate 7/8) Synchronization Time 8000 bits (maximum) Output Fault Indicators Activity detection of I and Q data sign bits...
  • Page 231 SNM-1001L Satellite Modem Revision 1 Decoder MN/SNM1001L.IOM The branch metrics are then processed by the ASC computer. The ASC computer makes decisions about the most probable transmitted symbol stream with the state metrics computed for the previous 64 decoder inputs.
  • Page 232 SNM-1001L Satellite Modem Revision 1 Decoder MN/SNM1001L.IOM This page is intentionally left blank. 14–6...

  • Page 233: Chapter 15. Reed-Solomon Codec

    Chapter 15. REED-SOLOMON CODEC 15.1 Reed-Solomon Codec Note: Refer to Chapter 2 Installation/Upgrades for Reed-Solomon installation. The modem must have the Reed-Solomon PCB installed to access this feature. The Reed-Solomon Codec PCB is a 4.75” x 6.00” (12.07 x 15.24 cm) daughter card located on the main PCB (Figure 15-1).

  • Page 234: Specifications

    SNM-1001L Satellite Modem Revision 1 Reed-Solomon Codec MN/SNM1001L.OM The Reed-Solomon Codec works in conjunction with the Viterbi decoder and includes additional framing, interleaving, and Codec processing to provide concatenated FEC and convolutional encoding and decoding. Refer to Figure 15-2 for a block diagram of the Reed-Solomon Codec.

  • Page 235: Reed-Solomon Encoder

    SNM-1001L Satellite Modem Revision 1 Reed-Solomon Codec MN/SNM1001L.OM 15.1.3 Reed-Solomon Encoder A block diagram of the Reed-Solomon encoder section is shown in Figure 15-3. The Reed-Solomon encoder section includes the following circuits: • Synchronous Scrambler • Reed-Solomon Codec (encoder section) •...

  • Page 236: Figure 15-4. Reed-Solomon Code Page Format

    SNM-1001L Satellite Modem Revision 1 Reed-Solomon Codec MN/SNM1001L.OM Since errors from the Viterbi decoder usually occur in bursts, a block interleaver with a depth of four is used in accordance with the INTELSAT-308 Rev. 6B specification. The interleaver has the effect of spreading out the errors across blocks of data instead of concentrating the errors in a single block of data.

  • Page 237: Reed-Solomon Decoder

    SNM-1001L Satellite Modem Revision 1 Reed-Solomon Codec MN/SNM1001L.OM 15.1.4 Reed-Solomon Decoder Refer to Figure 15-5 for a block diagram of the Reed-Solomon decoder section. The Reed-Solomon decoder section includes the following circuits: • Serial/Parallel Converter • RAM Deinterleaver • Parallel/Serial Converter •...
  • Page 238 SNM-1001L Satellite Modem Revision 1 Reed-Solomon Codec MN/SNM1001L.OM The term n - k = 2t is the total number of check bytes appended to the end of the data. The term’s k, n, and t will vary depending on the Reed-Solomon coding used. The Codec then sends the corrected data to a FIFO.

  • Page 239: Appendix Aspecification

    Appendix A SPECIFICATION Specifications The SNM-1001L satellite modem specifications are divided into sections as follows. • Specifications Summary • BER Specifications • Modem Specifications • Demodulator Specifications • Interface Specifications • Terrestrial Interface Types • System Specifications • BUC/FSK Communications...

  • Page 240: Specification Summary

    BPSK QPSK Offset QPSK 8-PSK Baseband Filtering IESS, Comtech EF Data Closed, Comstream Closed, EFD Closed Forward Error Correction (FEC) Viterbi, K=7, 1/2, 3/4, 7/8 rates Sequential 1/2, 3/4, 7/8 rates Reed-Solomon Concatenated per Intelsat Reed-Solomon Concatenated per closed network...

  • Page 241: L-Band Modulator Specification Summary

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM L-Band Modulator Specification Summary Table A-2. L-Band Modulator Transmit Specifications Output Connector Type N Female Frequency Stability ± 0.02 ppm Optional: ± 1.0 ppm Output Power Range 0 to -40 dBm in 0.1 dB steps ±...

  • Page 242: Demodulator Specification Summary

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM Demodulator Specification Summary Table A-3. Demodulator Specification Receive Specifications Input Connector Type F Female Input Impedance 75 Ω Input Return Loss ≥ 10 dB Minimum Input Level, Desired Carrier -135 dBm + 10*Log (Symbol Rate), see curve...

  • Page 243: L-Band Modulator Specifications

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM L-Band Modulator Specifications A.5.1 Digital Data Rate The digital data rate is selectable in 1 bit/s steps. The modem automatically calculates and sets the symbol rate. Data rates entered that exceed the data rate or symbol rate specification are rejected at entry.

  • Page 244: Modulation And Encoding Types

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM A.5.2 Modulation and Encoding Types The following combinations of modulation and forward error correction encoding are available. Table A-5. Modulation and Encoding Types Encoder Code Rate Reed-Solomon Modulation Viterbi, K7 BPSK Viterbi, K7...

  • Page 245: Scrambling Types

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM A.5.3 Scrambling Types When scrambling is enabled, it is applied to the modulator data according to the programmed modulator type as listed in the following table. When scrambling is disabled, no scrambling is applied to the modulator data.

  • Page 246: Modulator Spurious Emissions

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM A.5.5 Modulator Spurious Emissions Spurious emissions are measured relative to the power of an unmodulated carrier. The measurement is done with the carrier on in continuous mode and modulated by the correct data/clock signal. Spurious emissions measured in a 4 kHz bandwidth at the TX IF output are –55 dBc from 55 MHz to 2 GHz.

  • Page 247: Differential Encoder

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM A.5.9 Differential Encoder The differential encoder takes care of one set of ambiguities due to the error correction codes being transparent. • On or off A.5.10 BPSK Bit Ordering The encoder has the ability to select whether I is the first bit or Q is the first bit in the symbol word grouping for compatibility with any system.

  • Page 248: Modulator Power Offset

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM A.5.16 Modulator Power Offset An offset to the displayed IF output power may be entered from -99.0 to +99.0 dB, in 0.1 dB steps. A.5.17 Modulator I / Q Imbalance • The modulator will have less than 4° RMS phase error.

  • Page 249: L-Band Odu Supply Voltage

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM A.5.24 L-Band ODU Supply Voltage Standard configuration is without a power supply for the external ODU or outdoor unit. Two power options are available: • 24V at 100W • 48V at 150W During power up of the modem, the ODU supply voltage initially powers up in the OFF condition.

  • Page 250: Oqpsk Encoding

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM Using vector analysis of the constellation pattern, QPSK represents a symbol with the carrier phase angle at 45°, 135°, 225°, or 315°. The 1/2, 3/4, and 7/8 rates encoded provide the desired input/output bit rates.

  • Page 251: L-Band Demodulator Specifications

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM L-Band Demodulator Specifications A.7.1 Digital Data Rate The digital data rate is selectable in 1 bit/s steps. The modem automatically calculates and sets the symbol rate. Data rates entered that exceed the data rate or symbol rate specification are rejected at entry.

  • Page 252: Demodulation And Fec Decoding Types

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM A.7.2 Demodulation and FEC Decoding Types The following combinations of demodulation and forward error correction decoding are available. Table A-8. L-Band Demodulation and FEC Decoding Types Decoder Code Rate Reed Solomon Modulation Viterbi, K7...

  • Page 253: Descrambling Types

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM A.7.3 Descrambling Types When descrambling is enabled, it is applied to the demodulator data according to the programmed demodulator type as listed in Table 13-10. When descrambling is disabled, no descrambling is applied to the demodulator data.

  • Page 254: Receive Frequency

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM A.7.8 Receive Frequency The range of the input spectrum is from 950 to 1750 MHz, in 100 Hz steps. The actual value of offset from the programmed frequency is available to the operator on the front panel as well as the remote port.

  • Page 255: Receive Input Power (Composite

    The sum of all carriers is ≤ +50 dBc with respect to the desired carrier for symbol rates ≥ 64 Ks/s. A.7.15 Demodulator Input Shape The modem can be set to match any of the following spectral mask specifications. • Closed net (Comtech EF Data) • Closed net (Comstream) • Closed net (Fairchild compatible) A–17...

  • Page 256: Receive Input Power (Desired Carrier

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM A.7.16 Receive Input Power (Desired Carrier) The modem can meet the specified BER and automatically adjust to a receive input power. The minimum input signal level is –135 dBm + 10 log (Symbol Rate). E.g. (-98 dBm @ 4.8 Ks/s).

  • Page 257: Bit Error Rate Performance

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM Bit Error Rate Performance A.8.1 Performance With Noise, Viterbi Decoder, and Closed Network Required Eb/No BPSK and {O}QPSK 1/2 Rate 3/4 Rate 7/8 Rate 2/3 8PSK 10 -3 10 -4 10 -5 10 -6...

  • Page 258: Performance With Noise Turbo Product Codec (Optional

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM A.8.4 Performance with Noise Turbo Product Codec (Optional) Required Eb/No QPSK BPSK 8-PSK 1/2 Rate 3/4 Rate 21/44 Rate 5/16 Rate 3/4 Rate 10 -6 10 -7 10 -8 * 5/16 BPSK included for compatibility with other equipment but implementation limitations prohibit optimum performance at low Eb/No.

  • Page 259: Performance With Noise, 1544 Kbps Sequential Decoder (Optional

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM A.8.7 Performance With Noise, 1544 kbps Sequential Decoder (Optional) Required Eb/No BPSK and QPSK 1/2 Rate 3/4 Rate 7/8 Rate 10 -3 10 -4 10 -5 10 -6 10 -7 10 -8 Note: Offset QPSK with Sequential is not available.

  • Page 260: Acquisition Time

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM Acquisition Time The acquisition times apply for QPSK only. Viterbi 6 dB E b /N 0 with ± 35 kHz Frequency Uncertainty Code Rate Data Rate T acq P (t < T acq ) <...

  • Page 261: Receive Carrier Acquisition Range

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM A.9.1 Receive Carrier Acquisition Range 1. The modem will automatically lock to a correctly formatted carrier, which is within Acquisition Range of the displayed RX frequency. 2. The operator can adjust the acquisition range from 0 to 1 MHz, in 1 Hz steps.

  • Page 262: Interface Specifications

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM A.10 Interface Specifications A.10.1 TX Clock Switching Due to Failure of Selected Clock The modem will automatically switch the TX clock source to SCT internal on failure of terminal timing. A.10.2 TX Clock Phase Adjustment The operator can set the TX clock phase to Normal, Inverted, or Auto Mode.

  • Page 263: Doppler/Plesiochronous Buffer Clock Source

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM A.10.6 Doppler/Plesiochronous Buffer Clock Source The operator from the following sources can select the Doppler/Plesiochronous buffer clock reference. • The RX satellite clock (Bypass Mode). • The TX terrestrial clock (TT). Must be within ± 100 PPM of the nominal receive data rate.

  • Page 264: Receive Doppler/Plesiochronous Buffer Size

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM A.10.12 Receive Doppler/Plesiochronous Buffer Size The receive Doppler buffer size can be set by the operator from: 1. Bypass. 2. 32 to 262144 bits, in 16 bit steps for all data rates. 3. Selectable in ms, from 1 to 99 in 1 ms steps, for data rates < 2.6 Mbps.

  • Page 265: Offset Qpsk Decoding (Optional

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM Using vector analysis of the constellation pattern, QPSK represents a symbol with the carrier phase angle at 45°, 135°, 225°, or 315°. The 1/2, 3/4, and 7/8 rates provide the desired input/output bit rates.

  • Page 266: Terrestrial Interface Types

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM A.12 Terrestrial Interface Types The following interface types are available with electrical properties indicated in the following subsections: Modem Configuration EIA-422/ V.35 EIA-449 25-pin Connector 34-pin Connector 37-pin Connector 50-pin Connector 50-pin Connector (Optional) A.12.1...

  • Page 267: V.35 Specification V.10, V.11 Specification, Circuit Supported

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM A.12.2 V.35 Specification V.10, V.11 Specification, Circuit Supported Circuit Supported SD, SCT, SCTE, RD, SCR, DSR, RLSD, RTS, CTS, MC, DSR, LL Driver Amplitude (RD, SCR, SCTE, CTS, ± 0.5V-PK, ± 20% differential, into 100Ω...

  • Page 268: Eia-449/Eia-422 Mil-188-114A Specification

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM A.12.3 EIA-449/EIA-422 Mil-188-114A Specification Circuit Supported SD, ST, TT, RD, RT, DM, RR, RS, CS, MC ≥ ± 2V differential into 100Ω Amplitude (RD, RT, ST, DM, RR) Impedance (RD, RT, ST, DM, RR) <...

  • Page 269: Aupc Specification (Optional

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM A.13 AUPC Specification (Optional) Primary Data Rates Supported EIA-422 9.6 kbps to 2.048 Mbps V.35 9.6 kbps to 2.048 Mbps Asynchronous ESC Maximum Data Rate 1.875% of primary data rate Channel Interface EIA-232...

  • Page 270: Aupc Parameters

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM A.13.1 AUPC Parameters Table A-10. AUPC Parameters Local Automatic Uplink Power AUPC functions are available through the use of the optional . The Control (AUPC) operator can select local AUPC to be enabled or disabled.

  • Page 271: System Specifications

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM A.14 System Specifications A.14.1 Loopback Modes The operator can select one of the following interface loopback test modes. • Baseband: Near end and far end. • Interface: Near end and far end (Reed-Solomon or Overhead only).

  • Page 272: Remote Control

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM A.14.3 Remote Control All modem functions can be controlled remotely through the remote connector on the rear panel. See the Remote Specification for the complete command and response structures and syntax. Interface type: •...

  • Page 273: Stored Faults

    SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM A.15 Stored Faults All faults listed above will be stored in battery backed memory for up to 10 occurrences of each fault, along with the time and date of when the fault occurred, and, where applicable, when it cleared.
  • Page 274 SNM-1001L Satellite Modem Revision 1 Specifications MN/SNM1001L.IOM This page is intentionally left blank. A–36...

  • Page 275: Appendix B. Remote Control Operation

    Appendix B. REMOTE CONTROL OPERATION This appendix describes the remote control operation of the SNM-1001L. Firmware number: FW/8460-1M Software version: 2.1.12 Note: The firmware referenced in this manual may be an earlier version of the actual firmware supplied with the unit.

  • Page 276: Message Structure

    SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Message Structure The ASCII character format used requires 11 bits/character: • 1 start bit • Information and Parity bits (select one) • 7 information bits and 1 parity bit (Odd/Even) or 8 information bits (None) •...

  • Page 277: Command/Response

    SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM B.2.3 Command/Response The command/response portion of the message contains a variable-length character sequence which conveys command and response data. If a satellite modem receives a message addressed to it which does not match the established protocol or cannot be implemented, a negative acknowledgment message is sent in response.

  • Page 278: End Character

    SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM B.2.4 End Character Each message is ended with a single character which signals the end of the message: “cr” Carriage return character for commands “]” End bracket for responses B–4...

  • Page 279: Configuration Commands/Responses

    SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Configuration Commands/Responses B.3.1 Modulator Configuration Commands Modulator Command: <add/MF_nnnnn.nnnn'cr' Where: nnnnn.nnnn = Frequency in MHz, 950.0000 to Frequency Response: >add/MF_nnnnn.nnnn'cr' 1750.0000 in 100 Hz steps for non-terminal frequency RF_OFF'cr''lf'] display. Status: <add/MF_'cr'...
  • Page 280 SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Command: <add/MPO_snn.n’cr’ Where: snn.n = +99.0 to –99.0, in 0.1 dB increments. Modulator Response: >add/MPO_snn.n’cr’’lf’] Power Note: The modulator power offset is added to the nominal Offset Status: <add/MPO_’cr’ power level to adjust the transmit power range.

  • Page 281: B.3.2 Demodulator Configuration Commands

    SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM TX 8PSK Command: <add/T310_xxx’cr’ Where: xxx = ON or OFF. Response: >add/T310_xxx’cr’’lf’] IESS-310 Status: <add/T310_’cr’ Operation Response: >add/T310_xxx’cr’’lf’] TX FSK Command: <add/FSK_xxx'cr' Where: xxx = ON or OFF. Output Response: >add/FSK_xxx'cr''lf'] Status: <add/FSK_'cr'...
  • Page 282 SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Demodulator Command: <add/SDRV_nnnn_mmmm.mmm'cr' Where: Rate Variable Response: >add/SDRV_nnnn_mmmm.mmm'cr''lf'] nnnn = 1/2 (QPSK 1/2 Turbo and non-Turbo), Assignment [coder rate], 3/4 (QPSK 3/4 Turbo and non- & Selection Status: See DR command.

  • Page 283: B.3.3 Interface Configuration Commands

    SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Reed- Command: <add/RRSI_xx'cr' Where: xx = 4, 8, or 16. Solomon Response: >add/RRSI_xx'cr''lf'] Interleave Status: <add/RRSI_'cr' Value Response: >add/RRSI_xx'cr''lf'] RX 8PSK 2/3 Command: <add/R310_xxx'cr' Where: xxx = ON or OFF. IESS-310 Response: >add/R310_xxx'cr''lf']...
  • Page 284 SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Receive Command: <add/RCP_xxx'cr' Where: xxx = NRM (normal clock phasing), INV Clock Response: >add/RCP_xxx'cr''lf'] (inverted clock phasing). Phase Status: <add/RCP_'cr' Response: >add/RCP_xxx'cr''lf'] Baseband Command: <add/BBL_xxx'cr' Where: xxx = ON or OFF.

  • Page 285: B.3.4 System Configuration Commands

    SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM ASYNC Command: <add/TOBR_nnnnn'cr' Where: nnnnn = 110, 150, 300, 600, 1200, 2400, Transmit Response: >add/TOBR_nnnnn'cr''lf'] 4800, 9600, 19200, or 38400. Overhead Status: <add/TOBR_'cr' Baud Rate Response: >add/TOBR_nnnnn'cr''lf'] Note: TX ASYNC Overhead only.

  • Page 286: Automatic Uplink Power Control (Aupc

    SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Local Command: <add/LMA_xxx'cr' Where: xxx = ON or OFF. Modem Response: >add/LMA_xxx'cr''lf'] This command configures the modem for the LOCAL AUPC Status: <add/LMA_'cr' MODEM AUPC mode. When 'ON' is selected, the AUPC...
  • Page 287 SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM AUPC Command: <add/MAXP_snn.n'cr' Where: snn.n = -30.0 to -5.0, in 0.1 steps (nominal range Maximum Response: >add/MAXP_snn.n'cr''lf'] in dBm). Power Limit Status: <add/MAXP_'cr' Response: >add/MAXP_snn.n'cr''lf'] Notes: 1. The nominal power range is modified relative to the value specified by the modulator power offset (MPO_).

  • Page 288: B.4 Status Commands/Responses

    SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Remote Command: <add/RRES_'cr' Where: Interface Response: >add/RRES_nE-e'cr''lf'] n = 1 to 9 (error rate number). Read Error Example: e = 2 to 6 (exponent). Status Command: <add/RRES_'cr' Response: >add/RRES_2E-6'cr''lf'] Notes: 1. Received 2047 Pattern.
  • Page 289 SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Modulator/ Command: <add/MCP_'cr' Coder Response: >add/MCP_'cr' Config. SMT_xxxxxxx'cr' System Modem Type Program ITOT_xxxxx'cr' Interface Transmit Overhead Type Status MOM_xxxxxxx'cr' Modem Operation Mode MT_xxxxx'cr' Modulator Type MET_xxx'cr' Modulator Encoder Type MF_nnn.nnnnnnn'cr' Modulator Frequency (Non L-Band modem) MR_nnnn_mmmm.mmm'cr'...
  • Page 290 SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Notes: Data is only returned for TX D&I Overhead (or Flex Mux D&I). Data is only returned for TX IDR Overhead. Data is only returned for TX ASYNC Overhead Data not returned if Local AUPC is enabled & TX ASYNC/AUPC overhead.
  • Page 291 SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Demod/ Command: <add/DCP_'cr' Decoder Response: >add/DCP_'cr' Config. SMT_xxxxxxx'cr' System Modem Type Program IROT_xxxxx'cr' Interface Receive Overhead Type Status MOM_xxxxxxx'cr' Modem Operation Mode BERT_xxxx'cr' BER Threshold DT_xxxx'cr' Demodulator Type DDT_xxx'cr' Demodulator Decoder Type DF_nnnnn.nnnn'cr'...
  • Page 292 SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Interface Command: <add/ICS_'cr' Config. Response: >add/ICS_'cr' Status TC_xxxx'cr' Transmit Clock (Source) ERF_nnnnn.n'cr' External Reference Frequency TCP_xxxx'cr' Transmit Clock Phase RCP_xxxx'cr' Receive Clock Phase BBL_xxx'cr' Baseband Loopback ILB_xxx'cr' Interface Loopback ILT_xxx'cr' Interface Loop Timing...

  • Page 293: Odu Configuration Status

    SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM The Interface configuration status command causes a block of data to be returned by the addressed MODEM. The block reflects the current configuration of the interface. Additional configuration status of new options and features will always be appended to the end.

  • Page 294: Fault Status

    SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM B.4.4 Fault Status MODEM Command: <add/MFS_'cr' Faults Status Response: >add/MFS_'cr' (Summary) DMD_xxx'cr' Demodulator (FLT/OK) MOD_xxx'cr' Modulator (FLT/OK) ITX_xxx'cr' Interface Transmit Side (FLT/OK) IRX_xxx'cr' Interface Receive Side (FLT/OK) CEQ_xxx'cr' Common Equipment (FLT/OK)

  • Page 295: B.4.2 Error Performance

    SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Common Command: <add/CES_'cr' Equipment Response: >add/CES_'cr' Status M&C_xxx'cr' Monitor & Control Module (OK/FLT) INT_xxx'cr' Data Interface/Overhead Module (OK/FLT) BAT_xxx'cr' Battery/Clock (OK/FLT) +5_xxx'cr' +5V Power Supply (OK/FLT) +12_xxx'cr' +12V Power Supply (OK/FLT)
  • Page 296 SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Interface Command: <add/IRES_'cr' Where: Read Error Response: >add/IRES_tttt_xn.nE-ee'cr''lf'] tttt = FRM (FRAME) or 2047 (indicates type of error Status being read). x = < or > (data modifier to indicate that the error rate is less than or greater than the returned value).
  • Page 297 SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Receive Command: <add/RSL_'cr' Where: Signal Level Response: >add/RSL_xsnn.ndBm'cr''lf'] x = < or > (data modifier to indicate that the receive Status signal level is less than or greater than the returned value).

  • Page 298: Stored Faults

    SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Stored Faults Information on stored faults is returned when requested. If no stored fault exists for a given fault number, the words “NO Fault” will be returned instead of the normal time/date status information.
  • Page 299 SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Common Command: <add/CSF_#'cr' Equipment Response: >add/CSF_# hh:mm:ss MM/DD/YYYY'cr' Stored Faults M&C_xxx'cr' Monitor & Control Module (OK/FLT) INT_xxx'cr' Data Interface/Overhead Module (OK/FLT) BAT_xxx'cr' Battery/Clock (OK/FLT) +5_xxx'cr' +5V Power Supply (OK/FLT) +12_xxx'cr' +12V Power Supply (OK/FLT)
  • Page 300 SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Bulk Consol. Command: <add/BCAS_'cr' Analog Response: >add/BCAS_p1,p2,p3, . . . pn'cr''lf'] This command is similar to the 'BCS_' command, but Status returns modem analog parameters. Additional status of new options and features will always be appended to the end.
  • Page 301 SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Bulk Command: <add/BCS_'cr' This command causes bulk modem status to be returned. Consol. Response: >add/BCS_p1,p2,p3, . . . pn'cr''lf'] To reduce the length of the response, message parameter Status data are returned without identifiers. However, parameter identification can be determined by order of return.
  • Page 302 SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Bulk Consol. Status (continued) Parameter Parameter Name Number (Command Reference) Description Demodulator rate p17 = nnnn_mmmm.mmm, code rate/data rate in kbps. (ref. 'DR_' command). Demodulator preset A p18 = nnnn_mmmm.mmm, code rate/data rate in kbps.
  • Page 303 SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Bulk Consol. Status (continued) Parameter Parameter Name Number (Command Reference) Description Transmit clock phase p35 = n, where 'n' is '0' (NRM), '1' (INV), '2' (AUTO). (ref. 'TCP_' command). Receive clock phase p36 = n, where 'n' is '0' (NRM), '1' (INV).
  • Page 304 SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Bulk Consol. Status (continued) Parameter Parameter Name Number (Command Reference) Description Transmit data fault p53 = n, where 'n' is '0' (NONE), '1' (DATA), or '2' (AIS). (ref. 'TDF_' command). Receive data fault p54 = n, where 'n' is '0' (NONE), '1' (DATA), or '2' (AIS).
  • Page 305 SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Bulk Consol. Status (continued) Parameter Parameter Name Number (Command Reference) Description (Note 2) Demodulator Spectrum Rotation p71 = n, where 'n' is '0' (NRM), '1' (INV). (ref. 'DSR_' command). (Note 2) Reed-Solomon Encoder Enable p72 = n, where 'n' is '0' (off) or '1' (on).
  • Page 306 SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Bulk Consol. Status (continued) Parameter Parameter Name Number (Command Reference) Description (Note 5) ASYNC TX Channel Stop p89 = n, where 'n' is the current number of stop bits (ref. 'TCSB_' command).
  • Page 307 SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Bulk Consol. Status (continued) Parameter Parameter Name Number (Command Reference) Description RTS TX-IF Control Mode p107 = n, where 'n' is '0' (off) or '1' (on). (ref. 'RTSM_' command). CTS Delay Time p108 = nn, CTS delay time in seconds.
  • Page 308 SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Notes: 1. Data will only be returned if TX Overhead is programmed for Drop & Insert. Comma is always returned. 2. Data will only be returned if RX Overhead is programmed for Drop & Insert. Comma is always returned.
  • Page 309 SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Bulk Command: <add/BCSF_'cr' This command causes all modem fault status to be Consoli- Response: >add/BCSF_abcdefghijklmnopqr'cr''lf'] returned. To reduce the length of the response, fault status dated is embedded into the bit structure of the characters that are Status returned.
  • Page 310 SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Bit 5 = TX Audio Channel 1 Clip. Bit 4 = TX Audio Channel 2 Clip. Bit 3 = reserved. Bit 2 = reserved. Bit 1 = reserved. Bit 0 = reserved.
  • Page 311 SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Character 'r': Interface Reed-Solomon Unavailable Seconds Bit 6 = 1 always. Bit 5 = not used. Bit 4 = not used. Bit 3 through Bit 0 = Binary representation (0 to 10) of the number of Reed-Solomon Unavailable Seconds stored faults.
  • Page 312 SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Boot M&C Command: <add/BFI_'cr' Where: Firmware Response: >add/BFI_'cr' xxx.yyy.zzz = Software version number (0.0.0 to Information VER_xxx.yyy.zzz'cr' 999.999.999). FW/nnnnnn-ddr'cr' nnnnnn = Firmware number (0 to 999999). mm/dd/yy'cr''lf'] dd = Firmware dash number (0 to 99).
  • Page 313 SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Card #1 Command: <add/C1OI_'cr' Options/ Response: >add/C1OI_'cr' Misc. Information OH_01 list: s,G.703 'cr' (- or +) s,IBS 'cr' (- or +) s,ASYNC_AUPC'cr' (- or +) s,D&I 'cr' (- or +) s,IDR 'cr''lf']...
  • Page 314 SNM-1001L Satellite Modem Revision 1 Remote Control Operation MN/SNM1001L.IOM Serial Command: <add/SNUM_'cr' Where: xxxxxxxxx = Serial number 000000000 to 999999999. Number Response: >add/SNUM_'cr' MODEM_xxxxxxxxx'cr' Notes: CARD_1_xxxxxxxxx'cr' (Note 1) 1. Data is only returned if Card #1 is installed. CARD_2_xxxxxxxxx'cr' (Note 2) 2.

  • Page 315: Appendix C. Burst Mode Modulator Operation

    Appendix C. BURST MODE MODULATOR OPERATION Burst Mode Modulator: Theory of Operation The modulator is composed of two basic sections: the baseband processing section and the RF section. The modem M&C controls all programmable functions in both sections. C.1.1 Burst Mode From the front panel, TX Terrestrial or SCT can be selected for the modulator clock input.

  • Page 316: Burst Mode Modulator: Specifications

    SNM-1001L Satellite Modem Revision 1 Burst Mode Modulator Operation MN/SNM1001L.OM The output of the encoder generates two separate data streams to drive the in-phase and quadrature channels of the modulator. The data signal passes through a set of variable-rate digital Nyquist filters. There are activity detectors on both the In-phase and Quadrature (I&Q) channel Nyquist filters.

  • Page 317: Scrambling Types

    SNM-1001L Satellite Modem Revision 1 Burst Mode Modulator Operation MN/SNM1001L.OM C.2.3 Scrambling Types One of the following scrambling types can be selected by the operator. • A programmable seed 2^15 -1 Synchronous Scrambler. • None C.2.4 Differential Encoder The differential encoder is not needed as the data inversion ambiguity is resolved during acquisition.

  • Page 318: Phase Noise

    An offset to the displayed IF output power may be entered from -99.0 to +99.0 dB, in 0.1 dB steps. C.2.12 Modulated IF Output Shape The modem meets the following transmit output spectral mask specifications. The desired mask is selectable from the front panel or remotely. • INTELSAT/EUTELSAT • Closed net (Comtech EF Data) C–4...

  • Page 319: Spurious Emissions

    SNM-1001L Satellite Modem Revision 1 Burst Mode Modulator Operation MN/SNM1001L.OM C.2.13 Spurious Emissions Spurious emissions are measured relative to the power of the modulated carrier. The measurement is done with the carrier on in continuous mode and modulated by the correct data/clock signal.

  • Page 320: Transmit Preamble

    SNM-1001L Satellite Modem Revision 1 Burst Mode Modulator Operation MN/SNM1001L.OM C.2.17 Transmit Preamble In burst mode, when RTS transitions from false to true, the modem shall turn on the RF carrier and generate a burst preamble with the following characteristics: 96 symbols at 19.2 kbps...

  • Page 321: Burst Mode Demodulator: Theory Of Operation

    SNM-1001L Satellite Modem Revision 1 Burst Mode Modulator Operation MN/SNM1001L.OM Burst Mode Demodulator: Theory of Operation The demodulator card functions as an advanced, fully digital, coherent phase-lock receiver, and a Viterbi or Sequential decoder. C.3.1 Burst Mode The following subsections make up the demodulator: •...

  • Page 322: Burst Mode Demodulator: Specifications

    SNM-1001L Satellite Modem Revision 1 Burst Mode Modulator Operation MN/SNM1001L.OM Using Digital Signal Processing (DSP) techniques, the demodulator looks for carrier power in an 8 kHz bandwidth. When a carrier is detected, the DSP calculates the offset from the nominal frequency.

  • Page 323: Differential Decoder

    The modem will not be damaged by a continuous receive IF input of +20 dBm. C.4.10 Demodulator IF Input Shape The modem can be set to match any of the following spectral mask specifications. • INTELSAT/EUTELSAT • Closed net (Comtech EF Data) C–9...

  • Page 324: Channel Spacing/Adjacent Carrier Performance

    SNM-1001L Satellite Modem Revision 1 Burst Mode Modulator Operation MN/SNM1001L.OM C.4.11 Channel Spacing/Adjacent Carrier Performance The modem bit error performance will be degraded less than 0.5 dB with the following receive IF signal: • Two like-modulated carriers spaced 1.3 times the symbol rate from the receive frequency, and/or 1.2 times the acquisition range, whichever is larger.

  • Page 325: Collision Recovery

    SNM-1001L Satellite Modem Revision 1 Burst Mode Modulator Operation MN/SNM1001L.OM C.4.15 Collision Recovery A programmable packet length can be programmed from 48 bps to 1,048,576 bps in 1 bit increments. This allows for the demodulator to go back to acquisition mode when this parameter times out, in the case of a collision.

  • Page 326: Remote Control

    SNM-1001L Satellite Modem Revision 1 Burst Mode Modulator Operation MN/SNM1001L.OM C.5.2 Remote Control All modem functions can be controlled remotely through the remote connector on the rear panel. See the Remote Specification for the complete command and response structures and syntax.

  • Page 327: Figure C-1. Snm-1001L Burst Mode Fault Tree

    JX/Pin 17 ***** **** A connection between the common and N.C. contacts indicate fault. ***** Signal is open collector high impedance if faulted. A connection between the common and N.O. contacts indicate alarm. Figure C-1. SNM-1001L Burst Mode Fault Tree C–13...
  • Page 328 Pin 17 ***** **** A connection between the common and N.C. contacts indicate fault. ***** Signal is open collector high impedance if faulted. A connection between the common and N.O. contacts indicate alarm. Figure C-1. SNM-1001L Burst Mode Fault Tree (Continued) C–14...
  • Page 329 Pin 17 ***** **** A connection between the common and N.C. contacts indicate fault. ***** Signal is open collector high impedance if faulted. A connection between the common and N.O. contacts indicate alarm. Figure C-1. SNM-1001L Burst Modeode Fault Tree (Continued) C–15...

  • Page 330: Stored Faults

    SNM-1001L Satellite Modem Revision 1 Burst Mode Modulator Operation MN/SNM1001L.OM C.5.6 Stored Faults All faults listed above will be stored in battery backed memory for up to 10 occurrences of each fault, along with the time and date of when the fault occurred, and, where applicable, when it cleared.

  • Page 331: Burst Mode Specifications

    SNM-1001L Satellite Modem Revision 1 Burst Mode Modulator Operation MN/SNM1001L.OM Burst Mode Specifications General Specifications Operating Frequency Range 950 to 1750 MHz, synthesized in 100 Hz steps Type of Modulation QPSK Operating Channel Spacing Less than 0.5 dB degradation operating with 2 adjacent- like channels, each 10 dB higher at 1.3 times the symbol...
  • Page 332 SNM-1001L Satellite Modem Revision 1 Burst Mode Modulator Operation MN/SNM1001L.OM Additional Modulator Specifications Output Power -5 to -30 dBm, adjustable in 0.1 dB steps Output Spurious and Harmonics -55 dBc in 4 kHz BW in-band (50 to 180 MHz) -55 dBc in 4 kHz BW out-of-band (0 to 500 MHz) Output Impedance 75Ω...

  • Page 333: Glossary

    Glossary The following is a list of acronyms and abbreviations that may be found in this manual. Acronym Definition Ω Ohms 8-PSK 8-Phase Shift Keying Ampere Alternating Current Adjust Automatic Gain Control Alarm Indication Signal Amplitude Modulation ASCII American Standard Code for Information Interchange ASYNC Asynchronous AUPC...
  • Page 334 SNM-1001L Satellite Modem Revision 1 Glossary MN/SNM1001L.IOM Electronic Industries Association Electro-Magnetic Compatibility Engineering Service Circuit or Engineering Service Channel Electrostatic Discharge EXT REF CLK External Reference Clock FAST Fully Accessible System Topology FIFO First in/First Out Firmware Ground Hertz (cycle per second)
  • Page 335 SNM-1001L Satellite Modem Revision 1 Glossary MN/SNM1001L.IOM SYNC Synchronize Terminal Timing Transistor-Transistor Logic Transmit (Transmitter) TXCLK Transmit Clock Transmit Data Universal Brreakout box United States Volts Volts, Alternating Current Voltage-Controlled Oscillator Volts, Direct Current Viterbi Watt...
  • Page 336 SNM-1001L Satellite Modem Revision 1 Glossary MN/SNM1001L.IOM This page is intentionally left blank.

  • Page 337: Index

    AUPC - Between Two Modems, 10-4 Comparison of all TPC Modes, 7-4 AUPC with Reed-Solomon Option, A-32 Compatibility, 1-5 AUPC Modem Defaults, 10-8 Comtech EF Data Part Numbers, 1-3 AUPC Operation, 5-2 Command/Response, B-3 AUPC Parameters, A-32 Command Message Structure, 13-2...
  • Page 338 SNM-1001L Satellite Modem Revision 1 Index MN/SNM1001L.OM Demodulator Configuration Commands, B-7 Function Select: Configuration: Demodulator: Demodulator Configuration Status, B-16 Diff. Decoder, 4-19 Demodulator Faults, 9-6 Function Select: Configuration: Demodulator: Demodulator IF Input Shape, C-9 IF Loop Back, 4-20 Demodulator Input Return Loss, A-16...
  • Page 339 SNM-1001L Satellite Modem Revision 1 Index MN/SNM1001L.OM Target Eb/No, 4-35 Function Select: Monitor: Receive Signal, 4-40 Function Select: Configuration: Local AUPC: Function Select: Monitor: RX L-Band Freq, 4-46 Tracking Rate, 4-36 Function Select: Monitor: Sweep Frequency, 4-40 Function Select: Configuration: Local AUPC:...
  • Page 340 SNM-1001L Satellite Modem Revision 1 Index MN/SNM1001L.OM Function Select: Utility: Interface: Function Select: Utility: System: Modem Type: RX Overhead Type, 4-77 Local Modem AUPC, 4-92 Function Select: Utility: Interface: TX Data Phase, 4-78 Function Select: Utility: System: Function Select: Utility: Interface:...
  • Page 341 SNM-1001L Satellite Modem Revision 1 Index MN/SNM1001L.OM Overview, 1-1, 1-5, 1-9, 1-11 Outdoor Unit, 9-7 L-Band Demodulator Specifications, A-13 L-Band INMARSAT Spurious Emissions, A-8 L-Band Modulator Specification, A-5 L-Band Modulator Specification Summary, A-3 L-Band Control and Monitor, A-10 Performance with BPSK and {O}QPSK BER...
  • Page 342 SNM-1001L Satellite Modem Revision 1 Index MN/SNM1001L.OM Transmit Frequency Change Time, A-9, C-3 Transmit Packet, C-6 Transmit Postamble, C-6 Scrambling Types, A-7, C-3 Self-Monitoring Local Modem AUPC Control, 10-5 Transmit Preamble, C-6 Transmission Interface, 13-2 Send Clock Timing Source, A-24...
  • Page 343 METRIC CONVERSIONS Units of Length Unit Centimeter Inch Foot Yard Mile Meter Kilometer Millimeter 1 centimeter — 0.3937 0.03281 0.01094 6.214 x 10 0.01 — — 1 inch 2.540 — 0.08333 0.2778 1.578 x 10 0.254 — 25.4 1 foot 30.480 12.0 —...
  • Page 344 2114 85281 WEST TH STREET TEMPE ARIZONA 480 • 333 • 2200 PHONE 480 • 333 • 2161...

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