Resource Allocation for OFDM Cognitive Radio With Enhanced Primary Transmission Protection

Reducing interference to primary users and achieving good throughput are key objectives for secondary users in a cognitive radio (CR) network. In this letter, a rate loss constraint is considered in the sensing based spectrum sharing system of an OFDM CR network. Optimal resource allocation strategies including both sensing time and power allocation schemes are investigated to maximize the ergodic throughput of a secondary user under the rate loss constraints for primary users. A low complexity algorithm is introduced to characterize the optimal power allocation based on the sensing outcome at the SU. The effectiveness of the proposed resource allocation algorithms are demonstrated through simulation.