Adaptive orthogonal signaling with diversity in a frequency-nonselective Rayleigh fading channel

Power and rate adaptations with diversity are considered for M-ary orthogonal signals in a frequency-nonselective Rayleigh fading channel. We derived the minimum required E~_b/N₀ for a given probability of error, the maximum average data rate, and the outage probability, when maximal-ratio combining is performed with an imperfect channel estimation. We analyzed the effects of channel estimation errors on the required E~_b/N₀ and outage probability, as a function of diversity order and adaptation methods. The relative benefits of rate and power control techniques are further presented in terms of channel estimation error, diversity order, and outage probability. The minimum required E~_b/N₀ with Reed-Solomon codes is also presented for comparison purposes.