dears colleagues , i wanna ask about the On the downlink, the k-th QAM symbol,qk(with optional power weighting), is multiplied by the complex conjugate of the estimate for the mk-th channel coefficient,^gmk,and the weighted signals are summed over the K users to produce the signal that is fed into the m-th antenna how this signal deals with the actual channel is the relation is multiplication between matrix ( represend th signal data) and channel matrix? or the relation is convolution between the matrix ( represend th signal data) and channel matrix ?