PAGE CONTENTS
Objectives
Modern Telecom Satellites provide 45-60 transponders with Ku- and C-band frequencies.
Behind each channel is a TWTA (Travelling Wave Tube Amplifiers) or a MPM (Microwave Power Module) which is connected by an individual harness (cable of many parallel wires) to provide the power supply, send signals to switch MPM on/off or give gain step commands to the LCAMP (TC, Tele-Command) and get the unit status by telemetry (TM) signals.
Challenges
Telecommands and Telemetries of the LSSB protocol:
- Telecommands
- ALC / FGM Command
- Level / Gain Setting Command
- Mute ON / OFF Command
- ARU Enable Command
- ARU Disable Command
- Telemetries
- Level / Gain Step number Telemetry
- LCAMP Input Power Level Telemetry (in ALC)
- LCAMP Output Power Level Telemetry (in FGM)
- Mute Status
- Temperature Value Telemetry
- ARC Status
- Primary Current Telemetry
- TWT Helix Current Telemetry
- TWT Anode Voltage Telemetry
Plan
Most of the parallel EPC TM/TC signals are connected over the EPC to the LCAMP now. The LCAMP is converting this signal to the LSSB interface.
A new ASIC is the performing the central management of TM/TC vs. LSSB. The MPM on/off command and the power supply is not part of the LSSB interface.
Current Status
EPC to LCAMP interconnection designed/done, new ASIC designed, EPC and 2LCAMPs build and integrated as MPM(TWTA) and in testing. RF testing including LSSB sucessful finished. CDR and final report preparations.