Patent ID: 7933357

Claim:
A transmitter in a multi-user Multiple-Input Multiple-Output (MIMO) communication system, the transmitter comprising: a filter portion for receiving quantized Channel State Information (CSI) and Channel Quality Information (CQI) from a receiver, calculating a transmit filter value using the quantized CSI and the CQI, determining an appropriate Adaptive Modulation and Coding (AMC) level for the receiver, and sending a pilot signal including the transmit filter value and information about the determined AMC level on subcarriers in one of a preamble and data symbols; and two antennas for sending an output of the filter portion to a receiver and receiving data from the receiver; wherein the filter portion calculates the pilot signal including the transmit filter value by x k =M k ×1×√{square root over ( P t )}=√{square root over ( P t )} M k where k is used to identify the receiver and a subcarrier, x k is the pilot signal, M k is the transmit filter value, 1 is a known symbol to the transmitter and the receiver, and P t is transmit power for sending the symbol 1.