Resource Allocation in Uplink Multi-carrier MIMO systems for Low-complexity Transceivers

This paper proposes a resource-allocation method in a multi-carrier multiple-access channel with multiple antennas at the users and at the base station. Two additional constraints are imposed to reduce transceiver complexity. First, the number of users sharing a subcarrier is limited to the number of antennas at the base station, so that each receive dimension is not shared by more than one user; this reduces the decoding complexity of the receiver. Second, each user is forced to employ beam-forming by constraining its transmit covariance matrix to be rank-one. With these additional constraints, algorithms for user-selection and power allocation are presented. Numerical results show that the resulting sum-rate is very close to the sum-rate capacity and the user-selection does not affect the short-term fairness among users.