Fast Power Allocation Algorithm for Cognitive Radio Networks

A fast algorithm is proposed to tackle the optimal power allocation problem for orthogonal frequency division multiplexing (OFDM)-based cognitive radio networks, where the key is to replace the Newton step with O(N^3) complexity in the barrier method by a procedure with approximate linear complexity developed based on the structure of the optimization problem. Simulation results validate that our method can always work out the optimal solution, with complexity even lower than heuristic methods that can only produce suboptimal solutions.