Ultra-wideband impulse radio systems with temporal and spatial diversities

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