Closed-Form Outage Probability and BER of MIMO Zero-Forcing Receiver in the Presence of Imperfect CSI

Zero-forcing (ZF) detection is a simple and effective technique for retrieving multiple transmitted data streams at the receiver in multiple-input multiple-output (MIMO) wireless antenna systems. However the detection requires accurate channel state information (CSI) which may not be available in practice. In this paper, the impact of imperfect CSI on the performance of MIMO ZF receiver over uncorrelated Rayleigh flat fading channel is analytically assessed. In particular, tight approximation of the post-processing SNR distribution is derived and system performance in terms of outage probability and the BER of MPSK modulation is obtained in closed-form. The tightness of our analytical approximation is verified by the simulation results