Patent ID: 8532214

Claim:
A method of estimating channel state information for a plurality of wireless channels linking a transmitter and a receiver, each channel corresponding to a different transmit-receive antenna pair, the method comprising: grouping the plurality of channels into one or more groups, each group including the channels associated with two or more collocated transmit and/or receive antennas; iteratively estimating a set of delay tap values in the time domain for each group of channels so that the channels included in the same group are associated with the same delay tap values; estimating a frequency domain channel response of each of the channels included in the same group of channels based on the set of delay tap values estimated for the group; determining a sparse vector of M total delay taps for the channels included in the same group; identifying N most dominant ones of the M total delay taps, where N<<M; calculating a delay tap value for each of the N most dominant delay taps, wherein the N most dominant delay taps correspond to the delay taps included in the sparse vector having the largest delay tap values; calculating a value of a first ranking metric for each of the M total delay taps included in the sparse vector during each iteration, the first metric being a function of delay tap frequency domain response and a measure of residual error; and identifying the delay taps included in the sparse vector having the largest first ranking metric values during the same iteration.