Power allocation for sensing-based spectrum sharing cognitive radio system with primary quantized side information

Spectrum access approach and power allocation scheme are important techniques in cognitive radio (CR) system, which not only affect communication performance of CR user (secondary user, SU) but also play decisive role for protection of primary user (PU). In this study, we propose a power allocation scheme for SU based on the status sensing of PU in a single-input single-output (SISO) CR network. Instead of the conventional binary primary transmit power strategy, namely the sensed PU has only present or absent status, we consider a more practical scenario when PU transmits with multiple levels of power and quantized side information known by SU in advance as a primary quantized codebook. The secondary power allocation scheme to maximize the average throughput under the rate loss constraint (RLC) of PU is parameterized by the sensing results for PU, the primary quantized codebook and the channel state information (CSI) of SU. Furthermore, Differential Evolution (DE) algorithm is used to solve this non-convex power allocation problem. Simulation results show the performance and effectiveness of our proposed scheme under more practical communication conditions.