Investigates the performance of an adaptive trellis-coded modulation (ATCM) meteor burst communications system proposed by Jacobsmeyer [1987, 1989, 1992]. In those papers, Jacobsmeyer developed the theoretical performance of the system. A simulation was needed to verify two things about the proposed system: 1) would the Viterbi algorithm tolerate instantaneous code rate changes when the encoder is constructed with rate changing built into the encoder trellis, and 2) were the theoretical performance improvements based on asymptotic coding gain calculations valid? It turns out that the Viterbi algorithm can be used in an adaptive trellis-coding scheme to recover coded bits continuously throughout the trail lifetime at more than one information rate without loss of decoder trellis path memory. Also, the simulation results agreed very well with the theoretical predictions for coding gains and throughput improvement of ATCM over a fixed-rate BPSK system. At a bit error rate (BER) of approximately 10/sup -3/, theory predicted a throughput improvement upper bound of 3.32, and the simulation demonstrated an actual improvement of 3.08.
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