Evaluation of multi-user effects on the channel in the TH-UWB communication systems

This paper investigates the UWB channel to focus the light on the multi-user and their impact on the UWB communication performance. We addressed the performance evaluation of Time Hopping Ultra-Wideband (TH-UWB) system with the Pulse Position Modulation (PPM) by assuming multiuser scenarios. The channel used here is the IEEE 802.15.3a that consists of Channel Models (CM1∼CM4). Moreover, a Rake receiver is adopted to collect the multipath occurring in the UWB channel. Thus, the reception of signals requires a channel estimation stage (for amplitudes and delays) which is achieved here using the Maximum-Likelihood (ML) approach with two contexts i.e. Data Added (DA) and Non-Data Added (NDA). Simulation results confirm that the channel estimation is affected slightly by the multi-user in terms of amplitudes and considerably in terms of delays, and thus leads to focus much on multipath time resolution to gain better UWB communication accuracy and BER performance.