Blind equalization of a class of IIR channel

We examine some properties associated with twice oversampled IIR channels, and suggest a novel blind equalization scheme. We note that a twice oversampled IIR channel is equivalent to a single-channel feedback section in cascade with a two-channel feedforward section. We propose a two-step blind identification procedure for this class of channel, the performance of which we demonstrate by simulation. We note that such a procedure has particular application to channels with short feedback and long feedforward sections. We examine the nature of a Tomlinson-Harashima precoder, and show how a similar two-step blind identification can be applied when the precoder has a dynamics limited input