Fig. 7From: Solving hidden terminal problem in MU-MIMO WLANs with fairness and throughput-aware precoding and a degrees-of-freedom-based MAC designChannel frequency response. This is the frequency response of the channel with 64 subcarriers out of which 48 are occupied subcarriers, and the remainder are unoccupied subcarriers. The response is obtained by estimating the channel with the preambles sent by APsBack to article page