Performance of Equi-Correlated M-ary UWB-FSK Signals in Multipath

We study ultrawideband (UWB) communications over dense multipath channels using M-ary frequency shift keying (FSK) data modulation with both coherent and non-coherent detection. We present an M-ary FSK signal design that is able to balance the energy and correlation variations due to the frequency response of the antenna system and the frequency selectivity of the multipath channels. We calculate the bit error rate (BER) for different values of M and channel conditions. Numerical results show that large values of coding gains can be achieved with large values of M with a coherent detector.