Blind identification and equalization of MIMO FIR channels based on second-order statistics and blind source separation

In the single-user scenario in data communications, the identification and equalization of the channel can be accomplished blindly (i.e., without training sequences) using second-order statistics (SOS) if suitable diversity in the received signal is exploited. Diversity can be temporal, spatial, or both. In this paper one well known SOS based blind identification and equalization (BIE) of communication channels is extended to the multi-input scenario. It is shown that the application of this SOS-BIE procedure reduces the system to a problem of blind source separation (BSS) of instantaneous linear mixtures. The users' signals can then be recovered in a second stage through appropriate BSS techniques, typically requiring higher-order statistics.