Distributed Detection for Diversity Reception of Fading Signals in Noise

A multiple antenna diversity scheme is investigated for digital communications. Antenna observations are immediately quantized and sent to a fusion center. At the fusion center, the quantized observations are combined to form a nal decision on which symbol was transmitted. The optimum reception scheme is described for the case where frequency shift keying is employed and where slow Rayleigh fading and Gaussian additive noise are present. Two cases are studied. In the rst case, an accurate estimate of the signal-to-noise ratio is available at each receiver. In the second case estimates are not available. Results indicate that two or three bit quantizations may be most appropriate. Further, if binary decisions are made at each antenna, performance may not improve if an estimate of the signal-to-noise ratio is available at each antenna or if two antennas are used instead of one.