ROBUST CHANNEL ESTIMATION AND INTERPOLATION

摘要

Present robust 2D-MMSE or minimax approach assumes significant time and frequency selectivity due to which it has a poor MSE performance for RBs with low/ moderate frequency and/or time selectivity. Further, a filter cannot be designed assuming low frequency and/or time selectivity and use that for all channel models. The instant invention proposes Robust Adaptive (RA) MMSE filter that can bridge the gap between a robust 2D-MMSE/minimax and the optimal MMSE approach. Further, the RA-MMSE filter smoothens the filter coefficients of the robust 2D-MMSE filter with the degree of smoothing adaptively changing with amount of frequency and time selectivity within a RB. Further, the method uses multiple hypothesis tests on the maximum likelihood CFR estimates at the pilots. Further the RA-MMSE filter solves the minimax estimation problem with additional constraints on the autocorrelation sequence corresponding to the channel frequency response.