干扰受限的增量型机会中继选择协作通信

Incremental opportunistic relay selection cooperative communication with interference limited

协作通信让用户以协作的方式传输信息,是下一代无线通信系统为提升频谱效率所采用的关键技术之一。实际无线通信中的期望信号除了受到信道衰落和噪声的影响外,还可能受到来自其他用户同频信号的共道干扰。随着用户数的增加,大量的共道干扰就会取代噪声成为影响无线通信质量的主要因素,称为干扰受限。提出全网总功率约束条件下的增量型解码转发机会中继选择协作通信策略,并研究该策略在Nakagami/I.I.D.Nakagami信道衰落和干扰受限环境下的协作通信性能。理论分析和仿真结果表明,该协作策略能够在Nakagami/I.I.D.Nakagami信道衰落和干扰受限环境中有效抵抗信道衰落和共道干扰,实现协作分集增益。当源节点和中继节点的功率可以灵活调整时,合理的功率分配可以进一步提升协作通信性能。

Cooperative communication, which enables users to transmit information in a cooperative way, is one of the key technologies used in the next generation wireless communication systems to improve spectral efficiency. The expected signal in the actual wireless communication environment will not only be affected by noise and channel fading, but also may be affected by the co-channel interference (CCI) from other user’s signals in the same frequency band. A large number of CCI will replace noise as the main factor affecting the quality of wireless communication with the increase of the number of users, which is called interference limitation. An incremental decode-and-forward opportunity relay selection cooperative communication strategy under the constraint of total power of the whole network is proposed. The cooperative communication performance of this strategy in the environment of Nakagami/I.I.D.Nakagami channel fading and CCI with interference limited is studied. Theoretical analysis and simulation results show that the proposed cooperative communication strategy can achieve cooperative diversity gain, resist channel fading and reduce the influence of CCI with interference limitation effectively. When the power of source node and relay node can be adjusted flexibly, reasonable power allocation can further improve the performance of cooperative communication.