Commentary
Elavarasi R and Padmavathi
Abstract
In this paper, Cognitive radio technology is used to improve spectrum utilization and also to address the spectrum scarcity problem in the wireless networks. To fully utilize the primary spectrum and maximize the spectral efficiency, overlay and underlay transmissions, which exploits the white and gray spaces respectively, should be used together. Interference mitigation is a major issue in underlay networks and spectrum sensing is a crucial function in overlay networks. In the proposed work the entire spectrum is used for underlay transmission to minimize the PU interference and the spectrum holes are used for overlay transmission to maximize the data rate. An efficient green power control algorithm for hybrid overlay/underlay cognitive radio network is proposed. The performance (total achievable Bit error rate and throughput) of the proposed algorithm will be analyzed using MATLAB.