Implementation of MMSE Receivers Based on Diagonal Loading Method in Multipath Rayleigh Fading Channels

This letter focuses on the implementation of MMSE receiver in multipath Rayleigh fading channels, we present a new linear multiuser receiver with multipath combining, which can optimize the output signal-to-interference ratio (SIR) through diagonal loading method to implement MMSE detection. We obtain closed-form expressions for the SIR-optimized diagonal loading estimate. When the channel coefficient changes, the linear operator update of the new receiver can be implemented only by adjusting the diagonal loading quantity ,which doesn´t involve the matrix inverse computing. We show that the new receiver is equivalent to the conventional MMSE receiver ,but the former is easier to be implemented than the latter on fading channel.