In this paper, we consider a cognitive radio system, where multiple secondary users coexist with one primary user. To improve the transmission efficiency of the system, we propose a cooperative spectrum sharing protocol with secondary user selection by using decode-and-forward and two-path successive relaying techniques. Furthermore, we derive the close-form of outage probability of the primary system. The upper bound of outage probability of the secondary system is also derived. In addition, the theoretical results are verified via numerical simulations. Numerical results show that the primary outage performance is much better than conventional selective relaying schemes. In the low secondary Signal-to-Noise Ratio region, the secondary outage performance is also better than conventional selective relaying schemes.

中文翻译：

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5G无线网络中具有次要用户选择的机会性TPSR协作频谱共享协议

在本文中，我们考虑一种认知无线电系统，其中多个次要用户与一个主要用户共存。为了提高系统的传输效率，我们提出了一种协作频谱共享协议，该协议通过使用解码转发和两路径连续中继技术，具有辅助用户选择。此外，我们推导了初级系统中断概率的近似形式。还推导了二次系统中断概率的上限。另外，通过数值模拟验证了理论结果。数值结果表明，一次中断的性能比常规的选择性中继方案要好得多。在低次级信噪比区域，次级中断性能也比常规的选择性中继方案更好。