在认知无线网络的实际应用中,对于一些能量受限的认知用户来说,提高认知无线网络的能量效率尤其重要。该文从最大化认知无线网络能量效率的角度出发,考虑当认知用户在发送数据时突然出现的主用户信号引起碰撞冲突的情况,提出了对感知时间和帧周期进行分别优化和联合优化的单目标最优化问题,并进行理论推导分析。同时,实验仿真验证了理论分析的正确性。结果表明,能量效率分别随感知时间和帧周期的增大而先增大后减小,存在一组最优感知时间和帧周期使能量效率最大化。
In the practical application of cognitive radio network,it is especially important to improve the energy efficiency for those energy-constrained cognitive users. This paper is from the point of view of maximizing the energy efficiency in the cognitive radio network and considers the case that the primary user's signal which appears suddenly will bring the collision when the cognitive user is transmitting data. Then the single objective optimization problems which optimize the sensing time and the frame period separately and jointly are given. They are solved after the theoretical analyses which are also verified by the simulations.The results show that the energy efficiency firstly increases and then decreases with the increase of the sensing time as well as the frame period and there is a group of optimal sensing time and frame period to maximize the energy efficiency.