Iterative decoding of serially concatenated multilayered trellis-coded modulations in the presence of intersymbol interference and noise

We investigate a communication model made of an outer code interleaved with a space-time trellis coded modulation (ST-TCM). Such a scheme is very relevant for highly frequency selective and time-varying channels using turbo-detection at the receiver side, but inherently suffers from a low coding rate. One possible solution to alleviate this impairment (i.e., to increase spectral efficiency) is to use parallel (or multilayered) transmission as done in recent approaches (BLAST). However, parallel transmission and highly frequency selective channels involve tremendous complexity at the receiver side. We propose a low complexity turbo-detector based on reduced-state trellis search and generalized per survivor processing that proves to be very efficient in this resulting multiple-input multiple-output (MIMO) ISI channel context