Block based blind joint detection of co-channel signals over Rayleigh flat-fading channels with an antenna array

We consider joint detection of co-channel signals in Rayleigh fading without using special training signals or additional coding schemes-that is, blind detection. By appropriate selection of detector window size, we approximate the time variation of the channel gains as piecewise linear, and derive a new block blind maximum likelihood sequence estimator (BBMLSE). It appears this is the first paper to apply the block blind MLSE to time varying channels. Our algorithm is able to distinguish the co-channel signals and estimate the Rayleigh channels (within a phase factor) requiring as many antennas as co-channel signals. An efficient algorithm is presented, and simulation results demonstrate promising performance.