Multi-user interference performance comparison of direct-sequence impulse radio and direct-sequence UWB in AWGN

A new ultra-wide bandwidth communication system using both a time-hopping sequence and a direct spreading sequence, called direct-sequence impulse radio, has recently been proposed. The performance of this new scheme in multi-user interference is investigated. A precise expression for calculating the bit error probability of direct-sequence impulse radio is derived. Our precise analysis indicates that the Gaussian approximation substantially overestimates the performance at large values of signal-to-noise power ratio. Ultra-wideband communication systems employing time-hopping, direct-sequence and the newly proposed direct-sequence impulse radio schemes operating in multi-user interference are accurately compared in terms of the bit error rate. Our results indicate that direct-sequence impulse radio outperforms the time-hopping binary phase-shift keying system. However, its performance is poorer than the performance of conventional direct sequence binary phase-shift keying systems