Performance comparison of frequency domain processing and time domain processing in ultra wideband links

Ultra-Wideband (UWB) systems are considered excellent candidates for future-generation short-range, high-throughput wireless communications. Today, UWB transmit strategies include equally-spaced pulse positioning, time-hopping, and direct-sequence spreading. In this work, we begin by comparing the BER performance of all three UWB architectures in multi-path fading channels. We then propose a multi-carrier pulse waveform (named the Carrier Interferometry (CI) waveform) for UWB systems: When employing the Cl waveform at the transmitter, UWB receivers utilize a frequency-domain processing to exploit available frequency diversity gains (improving both performances and throughput). We compare the BER performance of equally-spaced pulse positioning, time-hopping, and direct sequence spreading UWB systems using traditional time-domain and the proposed frequency-domain processing. Simulation results suggest that frequency-domain processing in UWB systems leads to very significant gains in performance and/or throughput relative to time-domain processing.