This paper provides a framework for the analysis of error rate performance of maximal ratio combining multichannel reception of coherent linearly modulated systems over frequency-selective fading channels. Expressions for the error probability are developed, and the special cases for which closed-form or acceptable efficient numerical solutions are possible are delineated. A new efficient and accurate recursive method for the Ricean fading main resolved path case is presented for coherent quadrature amplitude modulation constellations. The effect of automatic gain control error on analysis of modulation schemes is demonstrated. Finally, numerical examples based on the maritime high-data-rate channel model are provided to demonstrate the usefulness of the framework.

This paper presents a recursive method for evaluating the error rate performance of multichannel reception of coherent MPSK systems operating over slowly Ricean fading channels. Each of the multiple channels is assumed to be a bandlimited two-sided discrete path model with complex Gaussian taps. The main path is assumed to be non-zero mean, corresponding to Ricean fading. Maximal ratio combining in the receiver is assumed, and an expression for the received phase density function is developed. A recursive method for solving the resulting error probability expression is then presented. This method is similar to those used for recursive computation of the Marcum Q function, and is both efficient and accurate. The method can be applied for both the flat and frequency selective Ricean fading cases. Examples based on a ship to ship high-data-rate line-of-sight channel model are provided to demonstrate the method.