Correlation in diversity systems with Rayleigh fading, shadowing, and power capture

The use of diversity techniques, such as dual receiving antennas, helps mitigate the effect of multipath fading in both the in-building and land mobile radio environments. A significant issue in the design of such systems is the degree to which correlation between the two or more diversity signals can be tolerated. In this paper, we consider the use of diversity techniques in radio systems that are subject to correlation, Rayleigh fading, log-normal shadowing and the radio capture effect. In the presence of two simultaneously transmitting stations, the throughput, conditioned on the local-mean power, is determined exactly for the case of a dual diversity receiving station. The insight gained from the two-station analysis is used to develop an accurate approximation for the case of a large number of stations. Parametric simulation studies are used to explore cases of an intermediate number of stations for varying system parameters (i.e., the capture ratio, power roll-off coefficient, and the amount of shadowing).