Multiuser interference modeling and suppression for a multichannel differential IR-UWB system

In a frame-differential, transmitted-reference (TR), impulse radio (IR) UWB system, operating in a dispersive multipath propagation and multi-access environment, the performance is, besides to noise, determined by the amount of inter-symbol interference (ISI) and multi-access interference (MAI). In this paper a multiuser multichannel equivalent system model accounting for ISI and MAI is derived to develop advanced detectors for these IR-UWB systems. A low complexity LMS algorithm is used to calculate optimal weighting coefficients for the fractionally-spaced, multichannel sample vectors acquired from the analog receiver front-end, to obtain an optimized decision variable. The achieved results are compared to the conventional single-channel system and to the results of a maximum likelihood sequence detection (MLSD) multiuser detection algorithm.