A Resource Allocation Scheme with Out-of-Band Interference Constraint in Cognitive Radio Systems

In the orthogonal frequency division multiplexing (OFDM)-based cognitive radio (CR) systems, adaptive resource allocation should consider the out-of-band interference. In this paper, allocation schemes with different optimization targets and multiple practical constraints are studied. Nonlinear equations for the optimal allocation are deduced. Two suboptimal methods based on bit removal procedure are also proposed. Simulation verifies that the proposed methods can reach a better tradeoff between the optimization target and other constrained performance.