CONVOLUTIONAL CODING FOR MULTIPLE-ACCESS SATELLITE COMMUNICATION

Abstract

Convolutional Coding with Viterbi Decoding, using a rate 1/2 constraint length 7 code, provides a 5 dB improvement in power-limited satellite communication if care is taken with tracking loops. Use with FDMA typically requires ambiguity resolution and differential encoding-decoding with one decoder and one demodulator per access. Time-sharing of one demodulator and decoder among several accesses is possible with TDMA if an aggregate rate buffer is provided and if control and timing loops are digitized, stored, and updated once per frame. A possible system is outlined.