UHF Communication relays
- Paper number
IAC-06-A3.P.05
- Author
Mr. Richard Blott, Qinetiq Ltd., United Kingdom
- Year
2006
- Abstract
The surface exploration of planets requires lightweight, high data rate communication systems. The Consultative Committee for Space Data Systems (CCSDS) have specified a two-way communication protocol, Proximity-1, for use in scenarios where a surface lander must communicate with an orbiter. QinetiQ have developed the hardware to implement this two-way communication. The system is currently in use on Mars Express, and the technology is available for future missions, both Landers and Orbiters. The use of the international Proximity-1 standard makes the QinetiQ system compatible with all current and planned missions. Although originally designed to support Beagle-2, the communication relay system on Mars Express has been used by NASA's Mars Exploration Rovers. QinetiQ also provided the communications system on the Beagle-2 Lander. The system operates at UHF, and supports data rates up to 128kbps. It combines convolutional encoding/Viterbi decoding with a Go-Back-N retransmission protocol to provide an extremely reliable communication path. The lander system, including antenna, weighs less than 900g and draws 25W when the 5W transmitter is switched on. The dual redundant orbiter system, including separate transmit and receive antennas, weighs less than 5kg and draws 30W with the transmitter on. The orbiter system also supports doppler ranging and an open-loop canister mode for detection of weak signals. The poster and accompanying datasheet describe the architecture and specifications in more detail.
- Abstract document