Cyclostationary-based diversity combining for blind channel equalization using multiple receive antennas

At high data rates, radio channels are characterized by severe intersymbol interference (ISI) and deep fades in the received signal levels. This paper develops an integrated approach for the mitigation of these effects using diversity combining and channel equalization in radio systems with multiple receive antennas. To accommodate higher data rates exceeding the channel coherence bandwidth, frequency selective channels are compensated utilizing blind equalization algorithms that exploit the cyclostationary signal structure inherent in communication signals. To mitigate the effects of flat fading, diversity combining is deployed which improves the bit error rate (BER) performance by merging distorted replicas of the transmitted signal in an intelligent fashion. This paper represents an effort in building on the strengths of these two distortion mitigation schemes so as to achieve additional benefit of compensating for channels that could not otherwise be compensated. The proposed combining algorithms are collectively referred to as cyclostationary-based diversity combining (CSDC). Both pre-equalization and post-equalization CSDC schemes are discussed in this paper. Simulation results for the performance of CSDC algorithms are presented.