【作者】 余洋；

【导师】 冯文江；

【作者基本信息】 重庆大学 ， 通信与信息系统， 2016， 硕士

【摘要】 带内全双工(IBFD)通信利用自干扰消除(SIC)技术能实现同时同频发射和接收,理论上可将频谱效率提高一倍。协作通信(CC)利用中继节点协作,能通过接力传输扩展覆盖范围,消除覆盖盲点、盲区,提高通信可靠性。将全双工通信与协作通信结合构建基于全双工通信的无线中继网络,不仅能发挥无线协作通信的技术优势,还能利用通信节点具有的全双工通信能力提高协作转发时效,降低端到端传输时延。但在全双工无线中继网络中,中继节点同时同频接收和转发信号,不可避免会存在残留自干扰(RSI),不同中继转发协议的性能与半双工无线中继网络有很大不同。本文针对全双工无线中继网络,分析和研究两跳中继和多跳中继下中继节点基于压缩转发(CF)协议的性能,主要研究内容和取得的研究成果如下:1)研究CF协议下全双工两跳中继网络的中断性能,首先建立全双工两跳中继网络的信道模型和信号模型,然后推导系统中断概率表达式,最后对中断性能进行仿真分析。结果表明:源节点和中继节点发射功率对系统中断概率有重要影响,随着发射功率的增大,系统中断概率呈下降趋势,但当发射功率增大到一定值后,系统中断概率下降趋缓;传输速率对系统中断概率也会产生影响,由于CF协议会引入量化噪声,当传输速率较小时,半双工方式略优于全双工方式,但随着传输速率的增加,全双工的优势逐渐体现;在相同传输速率下,CF协议下的系统中断性能次于SDF协议,但由于CF协议获得了分集增益,其中断性能优于DF协议。此外,R-D链路信道增益也会影响系统中断概率,但全双工方式始终优于半双工方式。2)研究CF协议下全双工多跳中继网络的中断性能,首先建立全双工多跳中继网络的信道模型和信号模型,然后推导系统中断概率表达式,最后对中断性能进行仿真分析。结果表明:信噪比对系统中断概率有重要影响,随着信噪比的增加,系统中断概率呈下降趋势,但当信噪比增加到一定值后,系统中断概率下降趋缓;在CF协议下,中继数一定时,随着信噪比增加,全双工的中断性能始终优于半双工。此外,由于在不同信噪比下,由于中继节点的总干扰以及路径损耗对性能的影响不同,因此,为了获得最小中断概率,应首先确定最优中继数量。更多还原

【Abstract】 In-band full-duplex(IBFD) utilizes self-interference cancellation(SIC) technologies for transmitting and receiving on the same frequency band at the same time, it has the potential to double the spectrum efficiency. Cooperative communication(CC) which transmits with the relay nodes’ cooperation, is able to improve coverage and eliminate the shadow area, and improve the communication reliability. Combination of the IBFD and CC in wireless relay networks should enhance the advantage of wireless cooperative communication, and increase the efficiency of forwarding and achieve lower end-to-end delay via full-duplex nodes. But different relay modes yield different performances between FD and half-duplex(HD) networks, the residual self-interference(RSI) still influences the network while relay nodes transmit and receive on the same frequency band at the same time. This thesis focuses on FD wireless communication network, analyzes the performance of two-hop and multi-hop networks with compress-and-forward(CF) protocol. The main contents are as follows:(1)Evaluation on the performance of two-hop compress-and-forward full-duplex relaying(CF-FDR). Primarily, the channel model and signal model are built, and a closed-form for the end-to-end outage probability is derived, also we simulate the outage performance on Matlab. The study shows that the transmit power of source node and relay node has a great effect on outage probability, that the end-to-end outage probability decreases with the node’s transmit power increment. However the outage probability yields lower reduction in high transmit power region. The outage probability also decreases as the transmission rates increases, and HD mode outperforms FD mode in low rate region due to the quantization noise for CF, but the FD mode has a better performance as the rate becomes higher. Because of the cooperative diversity, the outage performance of CF protocol is outperformed by SDF protocol while it outperforms DF protocol. The channel gain of R-D link significantly affects the outage performance, and FD mode performs better than HD.(2)Evaluation on the performance of multi-hop CF-FDR. First we build the channel model and signal model of multi-hop system, derive an approximate closed-form for the end-to-end outage probability, and simulate the outage performance on Matlab at last. The study shows that when the signal-to-noise ratio(SNR) raises, the outage probability which yields lower reduction in high SNR region decreases. With CF protocol, as SNR increases, FD mode outperforms HD. Due to the different the relay SNRs, the nodes’ number and the path-loss plays an important role in outage performance. In conclusion, minimum outage probability requires exact solution of optimal relay node number.更多还原