Patent ID: 7305042

Claim:
A communication system for transmitting digital communication signals between a transmit site and a receiver site comprising: at said transmit site, an M:1 multiplexer, wherein M is variable, having an M plurality of inputs coupled to receive up to M time division multiplexed digital communication signals; a rate 1/N convolutional encoder, where N is variable, coupled to the output of said multiplexer and being operative to output an encoded output signal modulated in quaternary phase shift keyed (QPSK) space having a prescribed symbol rate; at said receiver site, a rate 1/N Viterbi decoder which is operative to decode the encoded output signal output by said rate 1/N convolutional encoder; a 1:M demultiplexer having an input coupled to said Viterbi decoder and M plurality of outputs, and being operative to demultiplex the decoded signal from said Viterbi decoder into a plurality of M time division multiplexed digital communication signals, and wherein for any selected values for of M and N, the product of M and N is constant.