Ultra-wideband impulse radio with diversity reception

Abstract

Impulse radio (IR) is based on the Ultra-wideband (UWB) time-hopping spread spectrum technique in which sub-nanosecond of pulses are modulated to convey information by shifting the time position of the pulses. In this thesis, the influence of temporal and spatial diversities on the performance of UWB-IR system is analyzed. We investigate how antenna diversity can be used to improve the BER performance and cope with the effects of multiuser interference of IR system in multipath fading channel. Besides, we analyze the use of antenna array at the receiver to improve the multiple access capacity of the system in terms of the number of simultaneous users supported by the system for a given bit error rate and bit transmission rate. Numerical results show that the BER performance and multiple access capacity of the IR system can be improved significantly by increasing the number of array elements and coherently adding more number of paths at the receiver.