Decoding and performance of space-time trellis codes in fading channels with intersymbol interference

The design criteria of space-time trellis codes assume a flat fading channel without intersymbol interference (ISI). In this paper, decoding and performance of space-time codes is examined in a system for which the assumptions made for the criteria are not valid. We investigate a suboptimal joint equalization and decoding technique for space-time trellis codes to be used in frequency-selective fading channels and with pulse shapes causing substantial ISI. The performance of space-time codes is evaluated allowing different receiver complexity levels and compared to delay diversity and single-antenna transmission in a GSM EDGE based system. The results show a performance advantage for space-time coded systems in terms of block error probability. The observed bit error rates, however, indicate that successful concatenation of these codes with outer codes may not be straightforward when compared to simpler delay diversity transmission.