Telemetry Simulation; General; Operating Modes - Safran CORTEX CRT Quantum User Manual

Telemetry Simulation

3.4.3.

3.4.3.1. General

The Telemetry Simulator (TMS) allows for exhaustive testing of all of the software functionalities and hardware
resources in the CORTEX CRT Quantum:
Functional tests
Performance tests BER measurement in the presence of noise, by comparing bit by bit the PCM
For example, to set up a test loop at IF, the IFM output must be connected to the IFR input, either directly (if
necessary, insert an attenuator in the loop so that the IFR input level remains within -5 / -95 dBm) or via an
external IF Patch Panel or Matrix.

3.4.3.2. Operating modes

Here are the different operating modes proposed by the TMS:
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© Safran Data Systems
COMMAND RANGING & TELEMETRY UNIT CORTEX
CRT QUANTUM USER'S MANUAL
Telemetry reception
demodulation, bit synchronization, data decoding, frame synchronization).
signal generated by the TMS to the regenerated PCM from a bit synchronizer.
File: the modulating data are contained in files. Eight files per TMS are available on the
Hard Disk. The directory containing these 8 files is configurable in registry (see §
4.2.8.8.1). The file to be processed is selected owing to the parameter File Number, and
the Format Length defines the number of octets to be processed at the beginning of the
selected file.
Pseudo: the data are internally generated by a fixed polynomial which depends on the
selected PRN degree. This mode allows BER measurement by bit comparison between the
emitted data and the ones received by the Telemetry Unit selected owing to the parameter
TM Flow for BER. The generated unique frame contains first the Sync. Word
programmed in the associated TMU (according to the TMU Sync. Word Length), and
completes it with the pseudo data in order to reach the Frame Length configured in the
associated TMU too. The TMU Frame Synchronizer has to be enabled and locked.
If the configuration of the TMS or the associated TMU is changed, the TMS must be
restarted (set the TMS parameter Output to Disable and then to Enable).
LAN: the data are received on the TCP-IP Simulated port (SIM) for immediate modulation
(no storage on disk).
Replay: the modulating data are read from the storage buffer of a downlink Telemetry Unit
to be associated owing to the parameter TM Flow for BER. The complete file is replayed.
The directory containing the TMU storage files is configurable in registry (see § 4.2.8.3.2).
The index of the TMU storage file to be replayed is configured owing to the parameter File
Number, up to the upper limit of the TMU.
Do not activate this mode while storing data on the disk.
BERT File: the modulating signal is generated as in the case of File mode, and the BER is
measured by comparing the emitted data with the ones received by the Telemetry Unit
selected owing to the parameter TM Flow for BER. This processing can be performed only
on a unique repeated frame: the TMU Frame Length and the TMS Format Length have
to be configured at the same value. The TMU Frame Synchronizer has to be enabled and
locked.
This mode is useful for BER measurement purpose on repeated pattern.
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Safran Data Systems
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Ref. DTU 100042
Is.Rev. 5.17
Date: Dec.
03, 2021Sept. 30, 2021
noise (IF and baseband
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