Performance analysis of wireless LAN signals transmitted over a ricean fading channel in a pulsed-noise preference environment

Abstract

This thesis examines the performance of the waveforms specified by the IEEE 802.11a wireless local area network standard when the signal is transmitted over a Ricean fading channel with AWGN and pulsed-noise interference. The pulsed interference is assumed to have constant average power and is either fading or nonfading. The probability of bit error is conditional on the received signal-to-noise power ratio, which is modeled as a random variable. The probability density function of this random variable is obtained either analytically or numerically for each modulation type, and the probability of bit error is evaluated as the expected value of the conditional probability. In one case, use is made of a new technique for the numerical inverse of the Laplace transform in order to evaluate numerically the signal-to-noise ratio probability density function. Due to the complexity of the analysis when both the signal and the interference are subject to Ricean fading, the analysis was simplified by assuming Ricean signal fading with Rayleigh interference fading and vice versa. The results of the analysis show that performance is affected by the degree of signal fading and also depends on the pulsed interference duty cycle. The signal-to-interference power ratio affects the way performance depends on these two factors.