Optimal and Sub-optimal Power Allocation Algorithms for Goodput Optimization in Cognitive Multi-channel Wireless Systems

This paper studies the power allocation problem for a cognitive wireless system transmitting over multiple parallel channels. The goal of the power allocation is to maximize the total system goodput, or, the offered layer 3 data rate, keeping at the same time the interference caused to the licensed users, which transmit over the same bands of the cognitive device, under the prescribed threshold. This optimization problem results to be convex and then solvable with conventional numerical methods. Due to the high computational time required by these meth- ods, a sub-optimal approach is also proposed, offering a good trade-off between quality of solution and speed of the algorithm.