Frequency-offset Invariant Equaliser for Broadband Wireless Networks

An equaliser algorithm has been developed for use with a differential detector operating in a time dispersive channel. Although differential detection allows the stringent requirements on frequency accuracy generally imposed on coherent receivers to be relaxed, its performance is more severely degraded by intersymbol interference. The algorithm, described in this paper, provides reliable performance even after differential detection. Results for the differential equaliser operating in a typical indoor wireless channel are presented and are shown to be comparable to those of a coherent receiver, using decision feedback equalisation.