Optimal Power Allocation for OFDM-Based Cooperative Relay Cognitive Radio Networks
Cognitive Radio (CR) network with cooperative relay is potentially a promising technique to solve current spectrum inefficiency and spectrum scarcity problem. In this paper, the authors study the power allocation in Cognitive Radio (CR) networks with cooperative relay. The interference to the licensed primary system and the power budget of the CR network are jointly considered. The resulting model is general and the formulated optimization task generally hard to solve. To deal with the intractable coupling variables in the concerned problem, they propose an alternating optimization method, which can work out the optimal solution in an iteration manner and converges rapidly.