Trellis coded modulations on hybrid ARQ systems

The authors propose and analyze a hybrid automatic-repeat request (ARQ) scheme employing bandwidth efficient trellis coded modulation (TCM) and coded sequence combining. In this scheme, the TCM decoder, by performing sequence combining and soft-decision maximum likelihood decoding, makes full use of the information available in all received sequences corresponding to a given information message. It is shown, by means of analysis as well as computer simulations, that the scheme is capable of providing high throughput efficiency over a wide range of signal-to-noise ratios. The scheme is suitable for digital communication systems where high throughput and high reliability are required. >