A PERFORMANCE ANALYSIS OF TRELLIS-CODED MODULATION SCHEMES OVER RICIAN FADING CHANNELS

This paper presents a saddle point approximation (SAP) method to compu te the pairwise error probability (PEP) of trellis coded modulation (T CM) schemes over Rician fading channels. The approximation is applicab le under several conditions, such as finite and ideal interleaving, id eal coherent and pilot-tone aided detection, and differential detectio n. The accuracy of this approximation is demonstrated by comparison to the results of numerical integration. When ideal interleaving is assu med, an asymptotic approximation for the PEP of ideal coherent, pilot- tone aided or differentially detected TCM is derived. This asymptotic approximation of the PEP is in a product form and much tighter than th e ordianry Chernoff bound on the PEP. Also, based on the SAP, the effe ct of finite interleaving depth on the error performance of TCM scheme s over Rician and shadowed Rician channels is studied.