Performance of ultra-wideband time-hopping spread spectrum impulse radio systems with antenna array

Impulse radio (IR) is a time-hopping spread spectrum technique in which sub-nanosecond pulses are modulated to convey information exclusively in the relative time position of the pulses. In this paper, the influence of temporal and spatial diversities is analyzed on the performance of ultra-wideband impulse radio systems. We investigate how antenna diversity can be used to improve the bit error rate of the IR system in dense multipath environments. Numerical results show that the performance of the IR system improves when the number of array elements is increased. The performance can be further improved by coherently adding more multipaths at the receiver.