Adaptive Resource Allocation and Scheduling for Cognitive Radio MIMO-OFDMA Systems

In this paper, channel adaptive resource allocation and user scheduling problem for cognitive radio multiple-inputmultiple-output orthogonal frequency-division multiple access systems is investigated. Furthermore, stochastic approximation is employed to develop an on-line algorithm which is capable of adaptively learning the underlying channel distribution. The NP-hard combinatorial resource allocation and user scheduling problem is then solved through via the Lagrangian relaxation approach. Numerical results demonstrate the effectiveness of our proposed scheme.