High-rate transmission scheme for pulse-based ultra-wideband systems over dense multipath indoor channels

Abstract

A new high-rate transmission scheme is proposed for pulse-based ultra-wideband (UWB) systems over dense multipath channels. In contrast to the existing UWB schemes that transmit one short-duration pulse each pulse-repetition interval, the proposed scheme transmits a series of N (N/spl ges/1) consecutive pulses (a burst) each burst-repetition interval. The author then develops a successive, a zero-forcing (ZF), and a high-performance ZF-based successive receiver for effective detection in the presence of intersymbol interference within a burst. To lower complexity, an efficient algorithm for the ZF-based successive receiver is also derived. The error performance of these receivers, assuming the availability of perfect channel estimates over lognormal fading channels, is studied. Comparison is made between the proposed scheme and the conventional pulse amplitude-modulation scheme, when the transmission rate, the total transmitted power, and the channel delay spread are kept the same. Impacts of imperfect channel estimation are also studied by simulation. The proposed scheme could achieve a much higher throughput than the conventional scheme in dense multipath channels.