Variable length space time coded modulation

TL;DR: The VL-STCM scheme achieves its best performance for correlated sources, where the source symbols exhibit a nonuniform probability of occurrence and the higher the source correlation, the lower the achievable performance gain of the scheme.

Abstract: A Variable Length Space Time Coded Modulation (VL-STCM) scheme capable of simultaneously providing coding, multiplexing and diversity gains is proposed. The scheme advocated achieves its best performance for correlated sources, where the source symbols exhibit a nonuniform probability of occurrence. The source symbols are encoded using an optimal trellis encoder into variablelength modulated signals and mapped to both the spatial and time domains. More explicitly, the proposed VL-STCM arrangement is a jointly designed source coding, channel coding, modulation and spatial diversity/multiplexing scheme. It is shown that the higher the source correlation, the higher the achievable performance gain of the scheme. Furthermore, the performance of the VL-STCM scheme is about 6 dB better than that of the Fixed Length STCM (FL-STCM) benchmarker at a source symbol error ratio of 10?4.