Abstract
For Rayleigh fading channels, the primary code design criterion for a trellis coded modulation scheme is to maximize its effective code length (ECL), This paper concerns the design of optimal (l+1+l) Zp-convolutional encoders (OE) which, when combined with the continuous phase encoder (CPE) of continuous phase frequency shift keying (CPFSK) scheme, reaches the upper bound of ECL of a generic trellis coded modulation scheme. We develop sufficient conditions for the optimality of such a CE. The complexity for the test of thess sufficient conditions for a CE is also presented.