Patent ID: 8498193

Claim:
A method, comprising: determining, using a base station, sorting metrics for subscriber devices based on carrier channel characteristics for carrier channels of a wireless communication system; producing, using the base station, groups of the subscriber devices subject to a zero-forcing boundary condition, wherein a first one of the produced groups includes one of the subscriber devices having a maximum one of the sorting metrics and a last one of the produced groups includes a maximum number of the subscriber devices that successfully operate with respect to the subscriber device having the maximum sorting metric, wherein during testing of different subscriber group combinations, a non-iterative, closed-form formula is used to approximate a projection matrix for each subscriber device by calculating the product of the projection matrices of all other subscriber devices; and determining, using the base station, one of the produced groups of the subscriber devices to operate during a transmission period of the wireless communication system, wherein the wireless communication system uses space-division multiple access in combination with at least one additional orthogonal multiple access method, the at least one additional orthogonal multiple access method comprises frequency division multiple access, and the determining the sorting metrics, the producing the groups, and the determining the one of the groups are performed independently for each frequency channel of the frequency division multiple access.