认知无线电网络子空间映射频谱共享

Subspace Projected Spectrum Sharing in Cognitive Radio Networks

针对集中式多用户多天线认知无线电网络,分析了子空间映射能够为认知系统提供的通信机会以及理想信道条件下的空间子信道分配方案。在此基础上,提出了一种基于子空间映射的频谱共享策略。根据认知系统的感知结果,计算可以利用的空间子信道数,通过认知用户接入控制和子空间映射避免或抑制系统间干扰,从而在保证授权用户通信质量的前提下,为认知用户提供通信机会。仿真结果表明,与已有的子空间映射频谱共享方法相比,该策略不仅具有更高的认知系统可达和速率,而且能够为认知系统提供更多通信机会。

Through analyzing the analysis of transmission opportunities provided by subspace projection and spatial sub-channel allocation in ideal channel condition, a subspace projected spectrum sharing method is proposed for central multi-user multi-antenna cognitive radio networks. According to sensing results of the cognitive radio system（ CRS）, the number of available spatial sub-channels can be calculated. In order to guarantee the transmission of primary users （PUs） as well as provide transmitting opportunities to cognitive users（ CUs）, accessing control of CUs and subspace projection are adopted to avoid or reduce the interfer- ence between two systems. Simulation results show that, compared with existing spectrum sharing methods based on subspace projection, the proposed method can increase both the achievable sum rate and transmis- sion opportunities of CUs.