Joint pricing and resource allocation for OFDMA-based cognitive radio systems

Cognitive users can share spectrum with primary users under constraints on the interference that results. We present a new pricing strategy for sharing the primary users´ available subchannels with cognitive users by optimizing the secondary and primary users´ utilities while meeting the primary users´ interference constraints. The primary users aim to maximize their revenues by sharing their subchannels with secondary users while ensuring that they achieve a minimum target capacity. On the other hand, the secondary users aim to maximize their capacity under three different constraints: consumed power, a given budget for sharing subchannels, and tolerable interference caused to the primary users. We introduce a sequential procedure based on a distributed algorithm to determine the resource allocation, interference thresholds and prices that satisfy the requirements of both parties in the network. Simulations show that the users face a tradeoff between capacity, power, and price.