A technique for combining equalization with generalized differential detection

A generalized differential coherent detection technique combined with equalization for data transmission over intersymbol interference (ISI) channels is considered when carrier phase tracking is difficult. In the absence of ISI, the SNR performance of this generalized differential coherent structure is very close to the coherent detection bound. The authors present the integration of this generalized differential detection method with channel equalization, and therefore extend the applications of this detection technique to channels with ISI. It is shown that for high SNR, the performance degradation of this structure with respect to coherent detection and equalization is negligible. Analysis and computer simulation results show that this combined detection/equalization technique is an effective solution to the ISI problem when carrier phase tracking is difficult