Exploiting multipath activity using low complexity equalisation techniques for high speed wireless LANs

Recent developments have shown that there is considerable interest in wireless high-speed communications. While increasing data rates causes ISI cancellation problems, it also provides the opportunity to benefit from additional multipath diversity. The use of such diversity is not unique to equalised TDMA systems, indeed it has already been exploited in CDMA systems through the RAKE receiver. This paper introduces a new decision feedback equaliser (DFE) based on the use of a channel matched filter (CMF). The DFE coefficients are directly calculated from the uniform power delay profile of the CMF. The ISI cancellation accuracy obtained using this method is comparable to the conventional RLS-Kalman algorithm, however the computation load is significantly reduced. Performance comparisons and implementation benchmarks are given for an indoor 24 Mb/s (HIPERLAN) application.