In Wireless Regional Area Network, considering the actual licensed channel usage and weighting the channel utilization efficiency and system resources efficiency, a parameters optimization algorithm in cognitive radio is proposed. Simulation shows that the proposed algorithm can figure out the optimal sensing parameters for each licensed channel and maximize the sensing efficiency. Analyzed the channel utilization efficiency and selectivity of system resource utilization efficiency weighted affect cognitive efficiency. Moreover, the transmission duration can be improved significantly, if the anti-interference threshold of the system is large enough.