Transmitter induced cyclostationarity for blind channel equalization

Fractional sampling has received considerable interest recently as a means of developing blind equalization techniques without resorting to higher order statistics. Instead, cyclostationarity introduced at the receiver by fractional sampling is exploited. We show that simpler solutions are possible if cyclostationarity is introduced at the transmitter instead of the receiver. We propose specific coding and interleaving strategies at the transmitter that induce cyclostationarity and facilitate the equalization task. Novel batch and adaptive equalization algorithms are derived that make no assumptions on the channel zeros locations. Subspace methods are also proposed and, in the absence of noise, guarantee perfect estimation from finite data. Synchronization issues and bandwidth considerations are briefly discussed, and simulation examples are presented.