Noncoherent and Coherent Sequence Detection on Rayleigh Fading Channels

This paper compares noncoherent and coherent detection on Rayleigh flat fading channels. Based on a first-order Gauss-Markov channel model, we derive the error probabilities of noncoherent detection for full-response continuous phase modulation and differential phase-shift-keying modulation on both time-invariant and time-variant channels. Our result explicitly shows how the performance of noncoherent detection is affected by detector complexity, fading rate and operating signal-to-noise ratio. Based on our analysis, we propose a hybrid system which switches between a noncoherent detector and a coherent detector with imperfect channel estimates, in order to optimize the overall system performance in terms of service quality, receiver complexity and power efficiency