Trellis coded Q2PSK signals. I. AWGN and nonlinear satellite channels

Suitable bandwidth efficient coding techniques, to be combined with Q²PSK signals, are derived and analysed on AWGN and nonlinear channels. Five new Q²PSK TCs are presented. First, an expanded Q²PSK signal constellation has been used to design new 4D RI Q²PSK TCs. Partition of the 4D expanded Q ²PSK signal space into 2D subspaces has allowed the utilisation of any 8-PSK TC to be implemented along Q²PSK signals. This novel division of the Q²PSK signal space has been utilised to implement double 8-PSK TCs designed by Ungerboeck and double convolutional codes over ring modulo-8 along Q²PSK signals. Finally, an unexpanded Q²PSK signal has been considered to implement and design 2/4 and 3/4 rate Q²PSK trellis codes. Performance evaluation of coded and uncoded Q²PSK signals on nonlinear satellite channels is reported, and the results obtained from computer simulations of coded and uncoded Q²PSK on nonlinear channels are presented, where different amplifier working situations have been considered