Detailed formulas in closed or approximate forms are presented for calculating the distribution of the received bit energy-to-total-noise ratio. The parameters of Rayleigh fading statistics can be obtained from the multipath intensity profile. No predetermined number of effective multipaths is required and is decided during computation. The saddlepoint method can greatly reduce the calculation complexity to be linear with the number of interferers. Approximations are derived for a large processing gain. Various models of mobile locations are discussed. Uniform models for square and hexagonal cells are derived. Methods for computing the bit error rate are shown for receivers with an equal gain combiner and a selective combiner.
