A network device includes a first feedback module and a first calibration module. The first feedback module selectively generates a first transmission schedule that is transmitted to a link partner, wherein the first transmission schedule includes a first matrix map. The first calibration module selectively transmits a first set of training signals to the link partner, receives a first set of channel state information (CSI) for the training signals from the link partner according to the first transmission schedule, and generates a first CSI matrix based on the first set of CSI and the first matrix map.