Patent ID: 8442450

Claim:
A first network device, comprising: a calibration module configured to transmit a set of signals for each of a plurality of subcarriers from the first network device to a second network device, wherein the set of signals are used to train the second network device, and receive, from the second network device, elements of a matrix for each of the plurality of subcarriers, wherein the elements of a matrix for a subcarrier (i) represent signal to noise ratios of the set of signals for the subcarrier and (ii) are generated by the second network device based on the set of signals for the subcarrier received by the second network device from the first network device; and a feedback module configured to generate a schedule, in response to the schedule being not predetermined, by which the second network device is to transmit the elements of each of the matrices to the first network device, and transmit the schedule from the first network device to the second network device prior to the calibration module transmitting the set of signals, wherein the schedule indicates to the second network device (i) a sequence in which to transmit the elements of the matrix for each subcarrier from the second network device to the first network device, and (ii) an order in which to transmit the matrices for the plurality of subcarriers from the second network device to the first network device.