Design and performance of bit-interleaved pragmatic space-time codes in block fading channels

In this paper we introduce bit-interleaved pragmatic space time codes (BI-PSTC) and evaluate their performance over correlated fading channels taken into account by a block fading channel (BFC) model. More precisely, the BI-PSTC proposed here are obtained with the serial concatenation of a convolutional encoder, a bit-interleaver and a space-time mapper. A simple decoder based on a Viterbi algorithm with suitably defined branch metrics can be used, but iterative decoding can be also applied. In this paper we also discuss the diversity achievable and the performance of BI-PSTC obtained by using the classical optimal convolutional codes for AWGN channel and QPSK constellations. Performance evaluation shows that a considerable gain over known space-time codes can be achieved.