Patent ID: 8179844
Filing Date: 2012-05-15
Classification: H04L,H04W

Abstract:
1. A method, comprising: in an uplink transmission, receiving a Rank-1 channel quality indicator values from one or more subscriber stations, the channel quality indicator values being based at least in part on channel information; in an uplink transmission, receiving two or more vectors from the one or more subscriber stations; determining which of the one or more subscriber stations has a best Rank-1 channel quality indicator value; determining a beam-forming matrix based at least in part on the two or more vectors received from the subscriber station determined to have the best Rank-1 channel quality indicator value; in a downlink transmission, broadcasting to all of the subscriber stations the beam-forming matrix corresponding to the subscriber station determined to have the best Rank-1 channel quality indicator; and in an uplink transmission, receiving Rank-2 channel quality indicator values from the one or more subscriber stations; if a Rank-1 channel quality indicator value is greater than the Rank-2 channel quality indicator values from single subscriber stations or greater than the Rank-2 channel quality indicator values from multiple subscriber stations, then: selecting a single-user multiple-input, multiple-output Rank-1 mode for data transmission; and transmitting one data stream using the Rank-1 vectors for beam forming corresponding to the subscriber station having the best Rank-1 channel quality indicator value.