Instantaneous BER estimation, link adaptation and scheduling in multi-band OFDM UWB WPANs

Abstract

In this paper, we investigate Multi Band OFDM based UWB wireless personal area networks (WPANs) over time varying channels. To improve the efficiency of the data link layer we first propose a new method to model and estimate the bit error rate (BER) of the system based on the estimated channel state information (CSI). In order to maximize the link efficiency, we consider link layer Automatic Repeat reQuest with dynamically and optimally selected frame sizes according to the estimated instantaneous BERs. We also present a new opportunistic channel access scheme using IEEE 802.15.3 WPAN superframe structure. In this method, time allocations for individual links are proportionally determined with respect to their instantaneous efficiencies. Simulation results show that the proposed methods significantly enhance the efficiency of each link and the total network performance.