Blind equalization of sparse channels using antennas diversity

In this paper we consider the blind identifiability of multichannel systems when we know a-priori a bound on the number of non-zero coefficients in each channel. This is interesting for specular multi-path channels. We show that in this case, previously derived identifiability conditions are too strong. We demonstrate how to use the a-priori knowledge to weaken these conditions. We also propose a method to estimate the channel responses as well as the signals. Our method is based on a frequency domainLS estimation of the channel parameters combined with conditional MLE for the signals.