多天线认知无线电网络多信道联合频谱感知策略

当前，以单天线认知用户组成的认知无线电网络同时协作检测多个信道的分配策略得到了广泛研究，而在认知用户可以灵活选取自身天线进行空间分集接收的条件下，当联合感知多信道时，多天线认知无线电网络如何获取最优的天线分配策略仍有待进一步研究。为解决这一问题，在限制各信道最大虚警概率的前提下，以最小化所有信道漏检概率之和为目标，建立了优化模型，并提出了基于分支定界的算法和基于贪婪思想的启发式算法。前者可以获得最优策略，但复杂度较高，后者以牺牲较小检测性能为代价，明显降低了复杂度，有效实现了检测性能与复杂度的平衡，并且在保护各个信道上主用户免受认知用户干扰层面，一定程度上兼顾了公平性。 

Multi-Channel Coordinated Spectrum Sensing Strategy in Multiple Antennas Based Cognitive Radio Networks

Multiple-channel cooperative spectrum sensing in cognitive radio networks (CRN) based on cognitive radios with single antenna had been widely researched. However, it should be studied more to get the optimal antenna assignment in multiple-channel coordinated spectrum sensing for multiple antennas based cognitive radio networks when multi-antenna cognitive radios can flexibly select their antennas to apply spatial diversity reception. To solve this problem, we modeled it as an optimization problem with the constraint of the maximum false alarm probability of each channel and goal of minimizing the sum of misdetection probability over all the channels, and proposed two methods, branch and bound based method and greedy based heuristic method. The former can get the optimal strategy with high complexity, while the latter can reduce complexity obviously at the price of little loss of performance of detection and achieve a good trade-off between performance of detection and complexity, and care about the fairness to a certain degree on protecting primary users from interference of cognitive radios on each channel.