CONTENTS Chapter 1 Inmarsat System 1.1 System Overview LES ID List 1.2 Inmarsat C Services 1) Store-and-forward Telex Service 2) Communication Services 3) Code 1.3 Communications Network Inmarsat C Channels and Signals 1.4 Message & Signal Transfer 1-10 1. Ship-originated Call 1-10 2.
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Chapter 3 Block Description 3.1 General 3.2 Block Diagrams 1. Antenna and Communication Units 2. Terminal Unit 3.3 Functions of each board 3.4 Antenna Unit (IC-112) 3.5 Communication Unit (IC-212) 1. TX board (16P0157) 2. RF CON board (16P0147) 3. CPU board (16P0148) Chapter 4 Location of Parts 4.1 Antenna Unit (IC-112) 4.2 Communication Unit (IC-212)
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Chapter 6 Troubleshooting 6.1 Self-Test 1. Self-test at Power-up 2. Self-test by F7 Key (F7:Test) 6.2 Description of Status Monitor Display Analysis of NG Display 6.3 Error Messages 6-10 Appendix 1 Menu List AP1-1 Appendix 2 Specifications AP2-1 Parts List Circuit Diagrams...
Chapter 1 Inmarsat System 1.1 System Overview The Inmarsat system divides the world into four regions and each region is covered by its own satellite. The regions are Atlantic Ocean Region-East (AOR-E), Atlantic Ocean Region West (AOR-W), Pacific Ocean Region (POR), and Indian Ocean Region (IOR). The system consists of the bodies shown in the figure below.
LES ID List AOR WEST AOR EAST Perth Goonhilly France Telecom Burum Blaavand Sentosa Tangua Nakhodka Odessa Maadi Arvi Umm al Aish Fucino Thermopylae Jeddah Yamaguchi Santa Paula Sintra Southbury Kumsan Raisting Beijing Psary Boumehen Buitrago Laurentides Nonthaburi Goonhilly Goonhilly Thermopylae Singapore *:scheduled...
1.2 Inmarsat C Services The Inmarsat C system provides the following communication services. That is, all LESs supports these services. (1) Store-and-forward Telex message service (2) EGC (Enhanced Group Call) broadcasting (3) Distress alerting and safety services The following services are also available if supported by the CES selected. •...
2) Communication services TELEX: The MES can send and receive messages to and from a telex terminal connected to the international telex networks. The standard alpha-numeric character set known as Telex or ITA2 or 5-bit packeted. This character set is based on 5-bit codes, and supports only upper case characters, so any lower case characters entered on your MES will be received at the destination as upper case.
3) Code IA5: Known as ASCII, characters 7-bit codes. Supporting characters in messages sent or received using international alphabet 5. Specify this code to transmit English containing lower case alphabet. ITA2: Known as 5 bit packed. International Telegraph Alphabet 2 supports only upper case. Specify this code for message which contains only No.2 international communications alphabet.
1.3 Communications Network The illustration below shows the Inmarsat-C network. NCS/NCS Network Signalling Channel Coordination Station (NCS) NCS/CES NCS Common Channel Signalling Link Mobile Earth Station (MES) SES Signalling Channel Land Earth Data landlines Data Terminal Station SES Message Equipment (DTE) (LES) or Data Circuit Channel...
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4) SES message channel The SESs use this channel to transfer messages to a LES. Each LES has a number of SES message channels assigned to it by the NCS. Message transfer begins with the reception of a logical channel assignment packet. Allocation of SES message channels to SESs is done by the LES via the assignment packet.
Inmarsat C Channels and Signals Data Report Distress Polling Status Commission&Test Request Registration SES Status, SES Status Request TDM Assignment TDM Release Ack Land Eart Station Network Coordination Interstation Signalling Channel (LES) Station (NCS) Confirmation Acknowledgement Distress Announcement Response Data Assignment Response Announcement Polling Request...
1.4 Message & Signal Transfer 1. Ship-originated Call The following describes how an MES send a ship-to-shore message, using store-and forward techniques. Creating message Tunes to NCS CC NCS CC Decodes BB (LES network data) Transmitting message CES TDM Tunes to CES TDM Tunes to SES SES Sig.
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Ship-to-shore Message Transfer Steps 1. The MES normally receives via the NCS common channel, which contains network configuration information (LES frequency, etc.). 2. The MES tunes to the shore-to-ship CES TDM frequency for the required LES. 3. The MES sends an "Assignment Request" packet on a signalling channel associated with the CES TDM.
2. Shore-originated Call The following describes how a subscriber to the public telecommunications networks can send a message to an MES. Call Terrestrial subscriber Check if MES is logged-in. Message Stores all message. Check of MES status. • not in the region •...
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Shore-to-ship Message Transfer Steps 1. On receipt of the call over the public networks, the LES checks its MES database, to ensure that the MES is valid and logged-in. 2. The LES sends the result (MES status) to over the public networks. 3.
Login and Logout Each time the DTE and Communication Unit are turned on, the vessel should be registered with the Inmarsat C system to enable communications between vessel and CES. This is called login. If the vessel is not going to be using the equipment for a prolonged period it should logout from the Inmarsat C system so the vessel can be registered as inactive.
5. Distress Alert ( MES logged-in) Tunes to NCS CC NCS CC Decodes BB (LES network data) Permanently assigned TDM Channel Tunes to CES TDM (Continuous transmission on defined frequency) SES Signalling Channel Tunes to SES Signalling (DISTRESS ALERT) Channel CES TDM Tunes to CES TDM (DISTRESS ALERT ACK)
1.5 Different Classes of Inmarsat-C MES Different Classes of Inmarsat C MES are manufactured as below. The FELCOM12 belongs to class 2 MES. Class 1 MES This may be used only for ship-to-shore and shore-to-ship message transfer and distress alerting, but is not able to receive EGC messages. Inm-C Antenna Transmitter Receiver...
Chapter 2 Channel Types and Signal Processing 2.1 Channel Types A MES uses the following channels for the communications. 1) NCS Common Channel (NCS CC) 2) CES TDM Channel 3) SES Signalling Channel 4) SES Message Channel Details of each channel are tabulated below. NCS Common CES TDM SES Signalling...
1. NCS CC/CES TDM Channel The NCS common channel and CES TDM channels share a common overall structure. The TDM channels are based on fixed-length frames of 10368 symbols tarnsmitted at 1200 symbols/s giving a frame time of 8.64S. 10,000 frames are transmitted every day (8.64s x 10000= 24 hours).
2. Signalling Channel The SES signalling channel packet is always a fixed length of 15 bytes (120 bits). This channel is used for signalling from MES to LES and NCS. For example, the packet "Assignment Request" contains MES ID, LES ID, message size, and information of network to be connected.
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SES Signalling Channel Packet Types Packet Destination Acknowledgement Announcement Response Note) P: Priority (Distress, Assignment Response Normal) Clear Data Report NCS & LES C: Continuation (Last Distress Alert NCS & LES Distress Alert Test packet in sequence, MES Forced Clear NCS &...
3. SES Message Channel The message channels operate in TDMA mode and are controlled by the LES. Message channels are used by MESs to transfer messages to an LES. Each LES has one or more message channels assigned to it by the NCS. Allocation of a message channel to an MES is performed by the LES using assignment packets.
2.2 Signal Processing 1. Signal Processing Flow for Each Channel Message are processed on each channel as below. TX on NCS/CES RX on NCS/CES TX on SES TX on SES TDM Channel TDM Channel Signalling Channel Message Channel Message Message Message RX signal Scrambling...
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Convolutional Encoding The end of scrambled bit stream data of 120 bits is affixed with 6 bits of continuous flash bits and sent to the half-rate convolutional encoder which consists of a 7 bits shift register (constraint length-7) and two polynomials. 126 bits of signalling packet input are encoder to 252 symbols.
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The first 64 symbols of convolutional encorder output go to column 2, rows 0 to 63. The next 64 symbols to column 3, rows 0 to 63 and so on. The interleave block is transmitted on a row by row basis. The symbols in a row are transmitted in asccending order of column position;...
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BPSK Modulation BPSK is a kind of phase modulation using a digital signal. Depending on carrier phase difference, BPSK is expressed as 0 or 1. Data signal "0" is not phase shifted; data signal "1" is phase shifted 180 degrees. BPSK modulator Carrier BPSK modulated signal...
ANT, a diplexer: DIPLEXER, and a helical antenna. GPS position signals can be received with an optional GPS receiver board (GN-74) installed in IC-212. The GPS signals are not only utilized for FELCOM 12, but outputted therefrom in NMEA-0183 format. Outputted are GLL, GGA, VTG, RMC, and ZDA.
2. Terminal Unit (IB-581) COM 1 DET 1 CPU CARD T. BOARD IC-212 (AR-B1374) (16P0141) control COM 2 VGA CARD (AR-B1041) Power supply 80386SX-33 for LCD PRINTER PRINTER illumination SIMM MODULE (PP-510) × 256k FLASH ROM (AT29C040) KEYBOARD KEY BOARD (FD-235HF-7529) (BTC-5100C PS/2) ±5V/±12V...
3.3 Functions of Each Board Unit PCB Name PCB Type Function Remarks Consists of two pairs of antenna elements different in length, Helical ant. generating a right circular polarization wave. An isolation circuit between transmitting and receiving signals. Its Isolation is: Do not •...
3.4 Antenna Unit (IC-112) The transmitting signal from the Communication Unit (1626.5 to 1646.5 MHz) is supplied to Antenna Unit with an input level of -5 to +10 dBm. The signal is amplified in the ANT board a C-class amplifier which amplifies an input of -5 dBm to an output of +43 dBm ...
3.5 Communication Unit (IC-212) 1. TX board (16P0157) The TX board includes amplifier circuits and a transmission/reception switching circuit. The receiving signal from the Antenna Unit is supplied to the RF CON board through the transmission/reception switching circuit in the TX board. The switching loss of the receiving signal is less than 2 dB.
3. CPU board (16P0148) A simplified block diagram of the CPU board is shown below. The CPU board includes CPU1, CPU2, and interfacing circuits with outside. The functions of CPU1 are BPSK demodulation, and receiving signal processing, such as unique word detection, de-permutation, de-interleaving, Viterbi decoding, de-scrambling, and packet separation.
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CPU block CPU board consists of a pair of CPU1 and CPU 2 a demodulator, and a Viterbi decoder. Functions of each circuit are summarized as follows. CPU1: • Data entry of a receiving symbol every RX CLK • Synchronous detection by unique words •...
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Communication between DCE (Data Circuit terminating Equipment) and DTE (Data Terminal Equipment) The two units are connected by a serial I/O, using hardware that conforms to RS-232C, start-stop synchronization, and non-procedure protocol. Communications between DCE and DTE are in a free flow. However, DCE checks commands sent from DTE and returns its responses to DTE.
Chapter 4 Location of Parts 4.1 Antenna Unit (IC-112) Antenna element N-type coaxial connector Reflector Figure 4-1 Antenna Reflector Antenna element and reflector removed Note: Do not adjust any screws. Diplexer Diplexer cover Figure 4-2 Diplexer...
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Diplexer cover removed Cavity resonator Antenna base fixing screw (Hex. socket head bolt : M6 x 30 4 pcs.) Figure 4-3 Cavity Resonator Antenna base cover Antenna fixing hole (4xM6) Figure 4-4 Antenna Base...
Chapter 5 Maintenance 5.1 PV (Performance Verification) Test The PV test consists of the message reception test, message transmission test and distress alert transmission test. The results of the test appear on the PV Test Result display (see page 5-3). The MES-originated PV test proceeds in the following sequence.
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Procedure Be sure to Communication Unit is in idle condition and logged in before beginning the test. This test can only be conducted from the main DTE. 1. Press [7] to display the "option" menu. 2. Press [6] to display the Test menu. 3.
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How to display the results of the PV test 1. At the default display, press [F7] to display the Disp menu. 2. Press [6]. Options Test 1. PV Test 2. PV Test Result 3. Self Test 4. Distress Alarm Button Test 3.
5.2 LED Check The table below shows LED state on the PCBs. : on : blinking : off Board LED No. State Function CR 2 Blinks when CPU2 operates correctly. (GRN) CR 3 Lights when CPU2 error is detected. (RED) Blinks when unique words are detected CR 4 (on for 8.14 sec, off for 0.5 sec)
5.4 DIP Switch Setting External Alarm Setting All bits of the DIP switch S1 on the CPU board must be set to "OFF" position. If the switch is set to "ON" position, the received call unit IC-302 and/or the distress message controller DMC-5 cannot release alarm signal when a distress and an urgency (including EGC) message are received.
5.5 Memory Contents Backed-up by Battery Communication Unit: EE-PROM MES ID, Foward ID and Return ID is factory-programmed. When replacing the CPU Board (16P0148), remove the EEROM from the old board and put it on the new board. TP3 TP2 U11 (M6M80041P) : EE-PROM U44 : DEMOD U11 : EE-PROM...
Memory for Menu Settings Stored onto; Communication Terminal Communication FUNCTION Menu Remarks unit S- unit unit S- RAM:U40 (Flash RAM:U27 (Backed-up) ROM) (Not backed-up) 1. Transmit Message [F3] : Transmit 3. Request Delivery Status 1. Display EGC Message [F4] : EGC 2.
5.6 Updating System Program 1. Terminal Unit The following describes how to change the terminal software. *Terminal software number: 16501161xx Note) Flash ROM is assigned to Drive A, and floppy disk drive to Drive B. Procedure 1. While pressing and holding down [Alt] and [Fn], press [F2]. "OK to quit system Yes/No"...
2. Communication Unit The system program for the CPU2 in the communication unit is stored onto the flash ROM U26 on the CPU Board. Updating the software is made as follows. *Program Number for CPU 2: 16501181XX U26 contains loader program and system program. Procedure 1.
5.7 Replacement of Backup Battery The life of the lithium battery on the CPU board is about five years. The longer the time when the unit is off, the shorter the life of the battery. TP3 TP2 U44: DEMOD U11 (M6M80041P): EE-PROM U11: EE-PROM BUZZER Forward/Return ID programmed...
Chapter 6 Troubleshooting 6.1 Self-Test The self-test is carried out at every power-up, however you can diagnose the communication unit by using the self-test menu at any time. 1. Self-test at Power-up The communication unit is checked for proper operation each time the power is turned on. The conducted tests are;...
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2. Seft-test by F7 Key (F7:Test) Procedure 1. Press [F7] to display the Test menu. 2. Press [6]. 3. Press [3]. The Communication Unit test screen appears. Options Test Communication Unit Start 4. Press [Enter] to start the test. The message " Now Communication Unit testing" appears in blinking reverse video during testing.
6.2 Description of Status Monitor Display This section shows how to interpret the System Status Monitor. File Edit Transmit Reports Logs Options Setup Position StopAlarm Date 97-12-24 BBER Time 06:12 (UTC) OK (38dB) Send Level OK ( 0) Position LAT 35:00.00N RxIF AGC Level OK (133) LON 135:00.00E...
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GPS Status: GPS signal status CST: Cold Start ACQ: Acquired; Almanac data acquired IMP: Impossible; Cannot receive GPS signal INT: Interrupted; Object interfering with reception of GPS signal ALM: Receiving the almanac 2D, 3D: Position-fixing method by 2 or 3 dimensions DCE memory: Memory not is used.
Analysis of NG Display CN/NG NG appears, even if the equipment is operating normally when the satellite signal is weak. The CPU1 on the CPU board receives C/N data from the DEMOD circuit. If the signal level is below 31dB, NG appears, indicating that receiver circuit is defective, ocean region selection is incorrect, or blocking problem exists.
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Send Level NG Send level is calculated based on the current on the power supply line to the antenna unit. The current detector R51 locates at the output of the rectifier on the SW REG board. The signal detected by R51 is sent to U8, Q55 and Q51, and output to the CPU board as ANT CUR signal.
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Antenna Power Supply NG RX+18V/TX+29V, supply voltage to the antenna is divided by R61 and R62 to generate a monitor signal ANT VOL. The A/D converter (U71) receives the ANT VOL signal and sends it to the CPU2. If the voltage is not within the rating, “NG” will appear to indicate short-circuit and/or disconnection.
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REF Offset Freq NG CPU1 (U49) receives offset data generated by the DEMOD and finely adjusts the frequency of the reference oscillater VCXO. Based on the received signal, the oscillation frequency of TX/RX PLL synthesizer is adjusted to 15.6 MHz ±150Hz. When the offset frequency is more than 150Hz, “REF Offset Freq.
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Synthe 1st-1Local, 2Local, RX 2nd Local NG Synthe 1 st – 1 Local When the PLL (U15) unlocks, LD(Lock Detect) line becomes to “L” level. The CPU 2 receives the unlock signal and generates the NG indication. Synthe 1 st – 2 Local When the PLL (U10) unlocks, LD(Lock Detect) line becomes to “L”...
Please contact FURUNO. TROUBLE: Invalid MES ID . This equipment is deffected, Put EE PROM having vessel's EE PROM not installed. Please contact FURUNO. → TROUBLE: EE PROM ERROR Find out which circuit is TROUBLE: Synthesizer Synthesizer circuit is faulty.
Appendix 1 Menu List Function Menu 1 Menu 2 Menu 3 Menu 4 Menu 5 Short cut Key 1. New Alt+N 2. Open Alt+O 3. Close Yes or No Alt+Q 4. Save Yes or No Alt+S 5. Delete Yes or No Alt+D F1: File 6.
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Function Menu 1 Menu 2 Menu 3 Menu 4 Menu 5 Note Normal Priority Distress Message File Station Name Country / Ocean Code TELEX Station ID Country / Ocean Code Station ID Modem Type T30/V21--Other Address Destination E-Mail Subject No LES ID Type Attach File CSDN...
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Function Menu 1 Menu 2 Menu 3 Menu 4 Menu 5 Note Status Report Length DNID Destination LES ID Entry 1. Data Report (Yes/No) Member No. Interval Time Regular Interval Report Times Start Time 1 Activation Start Time 2 Daily Start Time 3 Start Time 4 PIN Code...
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Function Menu 1 Menu 2 Menu 3 Menu 4 Menu 5 Note 1. Send Message Logs 2. Receive F6: Logs Message Logs 3. EGC Logs 4. Logs 1. Login 2. Logout 3. Abort 4. Select NCS Auto West-Atlantic 5. Ocean Start East-Atlantic Region...
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Function Menu 1 Menu 2 Menu 3 Menu 4 Menu 5 Note LES ID Update Time Position Protocol Maritime Undesignated Fire/Explosion Flooding Collision Grounding 1. Distress Update Listing Message Setup (Yes/No) Sinking Nature Disabled &Adrift Abandoning ship Further assistance required Piracy or Armed attack Course...
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Function Menu 1 Menu 2 Menu 3 Menu 4 Menu 5 Note Telex Text Mode Ascii Insert Edit Mode Overwrite Word Wrap Line No. 3. Editor Setup 2 Cha Tab Width 4 Char 8 Char Telex(69 ) Fixed F8: Setup Column Width ASCII(40-80) Block...
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Function Menu 1 Menu 2 Menu 3 Menu 4 Menu 5 Note Additional Position Navarea Fixed Area Waypoint Station Code Ice reports Meteo.forecasts Pilot service Update 5. EGC Setup (Yes/No) DECCA messages LORAN messages F8: Setup OMEGA message SATNAV massages Other navaid (no message) Auto Log Print...
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Function Menu 1 Menu 2 Menu 3 Menu 4 Menu 5 Note 7. E-Mail Setup Update(Yes/No) Message Directory 8. Directories EGC Message Directory Station Name Country Code TELEX Station ID Country Code Station ID Modem Type T30/V21--Other E-Mail E-Mail Address Destination 1.
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