Resource Allocation for the OFDM-based Cognitive Radio System with Heterogeneous Delay-constraint Traffic ★

In this paper we study the resource allocation problem in Orthogonal Frequency Division Multiplexing (OFDM)-based Cognitive Radio (CR) networks with Delay-Constraint (DC) and Non-Delay-Constraint (NDC) users. The optimization objective is to maximize the sum capacity of the NDC users while guaranteeing the target rates of the DC users. The problem is formulated as a convex optimization problem which can be solved with high complexity. To reduce the computational complexity to an acceptable level, we propose an efficient algorithm by exploiting the structure of the problem. Simulation results show the proposed algorithm can always work out the optimal solutions with lower complexity compared to the standard convex optimization techniques, which makes it promising for applications.