Particle filter based stochastic interference cancellation for frequency-selective MIMO channel equalization

To mitigate the effects of the previous symbol decision errors of a decision-feedback (DF) equalizer on the current decision, a particle filter (PF) based DF equalizer for frequency selective multiple-input-multiple-output (MIMO) channel is proposed. On the basis of the analyses of DF equalization for the MIMO wireless system, it is found that a stochastic interference cancellation (IC) scheme can be employed to prevent the error propagation in a severe space-time interference scenario. This is because the random rather than the deterministic scheme can reduce the probability of an error decision even if an error decision occurs. Besides, the signal-to-interference-plus-noise ratio (SINR) based IC order, which is obtained via pilot, can guarantee the optimality of the cancellation. The bit error rate (BER) performance of the proposed scheme is verified through simulation experiments under different multipath interference environment.