中文摘要：

该文针对协作认知无线电网络提出一种时域、频域和空域资源联合分配的传输机制，在改善授权用户传输性能的前提下使参与协作的认知用户获得合理的回报。所提机制利用多天线认知节点担任中继，通过自适应的时隙划分与带宽分配，对两跳传输链路中的瓶颈予以消除：并在包含多个协作认知用户的场景中，给出一种考虑公平性的中继选择算法。该方法一方面采用比例公平的思想实现认知用户间的公平性，另一方面通过调整奖励因子，使中继获得合理的回报。仿真结果表明，所提算法能够改善授权与认知系统的数据速率，同时给予认知中继公平的回报。

英文摘要：

A transmission mechanism based on the joint management of time, frequency and space domain resources is proposed in the Cooperative Cognitive Radio Network （CCRN）, with which the cooperative cognitive users can obtain proper reward under the premise of improving the primary user＇s transmission. The proposed scheme employs multi-antenna cognitive user as a relay. Via adaptive time-slot and bandwidth allocation, bottleneck in the two-hop transmission can be eliminated. Furthermore, a relay selection algorithm taking fairness into account is given for the situation where multiple cooperative cognitive users exist. On one hand, the relay selection utilizes proportional fair to achieve inter-cognitive-user fairness. On the other hand, proper reward is determined by adjusting the incentive factor. Simulation results show that the proposed mechanism can improve the data rate of both primary and cognitive systems, and afford fair reward to the cognitive relays.