Performance evaluation of digital microcellular radio systems with Rician fading and correlated shadowing

Abstract

Bit error rate (BER) performance of digital microcellular radio systems is investigated using differential phase shift keying (DPSK) in an environment with additive white Gaussian noise (AWGN), co-channel interference, Rician fading and correlated log-normal shadowing. The BER was observed to be reduced considerably by the presence of correlated shadowing suffered by the desired signal and co-channel interferers. The spectrum efficiency in a correlated shadowing environment is significantly improved compared to the uncorrelated case. The effects of energy per bit per noise power density (E<inf>b</inf>/N<inf>0</inf>), data rate, correlation coefficient, carried traffic, shadow spread and Rice factor is investigated. The BER performance is compared for the two shadowing models considered. In the first model, only the line-of-sight (LOS) component of the Rician-faded desired signal is assumed to undergo log-normal shadowing, while the diffuse components are unaffected by it. In the second shadowing model, LOS and diffuse components of the desired and co-channel interfering signals suffer correlated log-normal shadowing.