High-level modulation and coding for nonlinear satellite channels

Ungerboek (1982) has proposed a class of codes in which a constellation of 2M signals is used to transmit data at the rate of log(2) M bits/symbol, and has shown that coding gains of up to several dB are achievable in the additive white Gaussian noise channel without increasing bandwidth occupancy. Attention is presently given to the performance of this class of codes when employed in the transmission of 3 data bits/symbol on a band-limited, nonlinear satellite channel. It is found that 16-PSK outperforms the 16-QAM and 16-ary modulation formats, and that the use of these codes can yield substantial performance improvement on even a satellite channel.