Iterative equalization and decoding with channel shortening filters for space-time coded modulation

Abstract

We consider space-time trellis coded modulation in frequency selective channels. We discuss the outage capacity of space-time trellis coded modulation compared to the capacity of the underlying MIMO channel. Furthermore, we derive FIR channel shortening filters which are used as pre-filters for turbo equalization in order to reduce the number of equalizer states. We show that we can compensate for part of the performance loss due to channel shortening by turbo iterations and a transformation of time diversity to a form of spatial diversity.