Patent ID: 8243690
Filing Date: 2012-08-14
Classification: H04L

Abstract:
1. A bandwidth allocation method performed by a base station, the method comprising: receiving, over a bandwidth request contention channel, orthogonal sequences sent in two or more tiles during an uplink subframe from subscriber stations, the orthogonal sequences being selected by the subscriber stations from a set of orthogonal sequences, each of the two or more tiles comprising a time-frequency block; and detecting one or more of the subscriber stations by applying each of the orthogonal sequences of the set to the received orthogonal sequences; broadcasting in a downlink subframe, the orthogonal sequences corresponding to the detected subscriber stations and an assignment of one of a plurality disjoint pilot patterns to each detected subscriber station; and receiving uplink bandwidth request messages in the next uplink subframe from the detected subscriber stations in accordance with the disjoint pilot patterns assigned to the detected subscriber stations, wherein the base station receives the orthogonal sequences from the subscriber stations through a plurality of antennas and uses a space-division multiple access (SDMA) technique to help differentiate two or more of the orthogonal sequences that have collided.