认知Ad Hoc网络能量有效频谱接入策略

摘要

针对认知无线Ad Hoc网络中次用户能量受限问题,提出一种基于能量有效性的机会频谱接入策略.联合考虑信道状态的时变性和次用户的频谱感知准确性,基于部分可观测马尔科夫决策过程(POMDP)建立了一种最大化能量有效性的分析架构,指导次用户选择能效最佳信道,并根据信念状态、信道增益和检测概率,自适应控制传输功率.仿真结果表明,该策略能够有效提高次用户传输的能量有效性,通过对传输功率的有效控制,实现了传输性能和能量开销的有效折中.%A novel opportunistic spectrum access strategy based on energy efficiency was proposed to solve the energy constrain issue of a secondary user in cognitive radio ad hoc network,in which a secondary user sensed the channels licensed to some primary users sequentially before it decided to transmit.We developed an analytical framework to maximize energy efficiency based on partially observable Markov decision process (POMDP) through jointly considering the time-vafiance characteristic of wireless channels and the accuracy of spectrum detection.The framework could lead secondary user to select the channel with the best energy efficiency and adaptively control the transmission power according to channel belief state,channel gain and detection probability while meeting the secondary user's service requirement.Simulation results indicate that the proposed strategy can improve the energy efficiency of the secondary user's transmission and achieve the tradeoff between the transmission performance and energy overhead by efficiently regulating the transmission power during its battery life.