Interference Management and Rate Adaptation in OFDM-Based UWB Networks

Ultrawideband (UWB) communications has emerged as a promising technology for high data rate wireless personal area networks (WPANs). Several proposals for UWB-based WPANs have been made. One widely popular proposal was standardized by ECMA-368, and is based on OFDM. In this paper, we address one of the important aspects that impact the performance of this standard, namely interference management between different uncooperative beacon groups that operate simultaneously over the same area. We first propose an interference management distributed reservation protocol (IM-DRP) for OFDM-based UWB communications. IM-DRP aims at improving the throughput of an UWB WPAN by reducing interference between uncooperative beacon groups. We then integrate IM-DRP into the design of a rate adaptation strategy that exploits the multirate capability of OFDM-based UWB systems. Besides maintaining a target packet error rate, our proposed strategy attempts to reduce the required reservation time over a link, hence allowing more links to be simultaneously activated. This improves the overall network throughput. Simulations are used to demonstrate the performance gain of our proposed schemes.