Bit error rate analysis for TH-CDMA/PPM impulse radio networks

This paper is concerned with error rate performance analysis of ultra-wide bandwidth time-hopping multiple access radio networks employing binary pulse position modulation. Under the assumption of rectangular pulses, we derive an exact expression for the probability of bit error of a TH-CDMA/PPM signal subjected to K interferers in the AWGN channel. This is used to assess the accuracy of the Gaussian approximation commonly used in the performance analysis of UWB impulse radio networks. It is shown, through numerical results, that bit error rates obtained by Gaussian approximation underestimate the exact results. Moreover, the errors due to Gaussian approximation become significant only for systems with low number of pulses per information bit.