A multiple trellis coded Q2PSK system for personal communication

In this paper the performance of multiple trellis-coded modulation (MTCM) codes for application to a Q²PSK personal communication system, are investigated. This paper considers, based on the optimum design criteria for the design of MTCM codes over fading channels, the design of new 4-state codes for Q²PSK. The benefits in using channel state information based on fading channel estimates in conjunction with the MTCM decoder through a suitable metric weighting function are also considered. The channel estimates are obtained from sequences of known header and pilot symbols embedded in the information stream. This technique is shown to provide remarkably robust performance in the presence of fading. The bit error rate performance of the MTCM code designs (including channel side information), assuming coherent detection and perfect carrier and time synchronization, are then studied by means of simulation for cellular radio channels. It is shown that coding gains in excess of 14.0 dB at a bit error probability of 10^-4 can be achieved with the MTCM coded system, relative to the uncoded system on Rayleigh fading channels