Performance Analysis of Multi-User DS-UWB System under Multipath Effects

For the multi-user application the multiple access interference (MAI) due to imperfect orthogonality between spreading codes induced by UWB dense multi-path significantly degrades system performance. Over the past few years, performance analyses for various UWB systems in an AWGN environment have been presented. However, those works did not consider UWB multipath effect; thus leading to an unacceptable analytical result. To compensate for the shortage of previous works, this research aims to theoretically derive accurate performance of DS-UWB system in the presence of AWGN, MAI, and multipath effect. The BER performance will be analyzed in terms of the number of active users. An upper bound on the maximum number of users supported by the system will be derived. In addition, the allowed multiple access transmission rate will also be evaluated. Key-Words: Multiple Access Interference (MAI), Multipath Channel, Direct Sequence Ultra-Wideband (DS-UWB)