%0 Journal Article
%T 2×2 X信道和PTP信道并存网络的自由度<br>Degrees of freedom of networks with coexistence of 2×2 X channel and point-to-point channel
%A 郭倩倩
%A 刘锋
%A 曾连荪
%A 覃闻铭
%J 北京航空航天大学学报
%D 2016
%R 10.13700/j.bh.1001-5965.2015.0696
%X 摘要 自由度（DOF）是一个空间复用概念，是在多天线系统中引入的，体现了无线信道对空间资源的利用效率。在认知无线电中，由于主、次网络会相互干扰，从而会降低DOF。本文主要研究的是2×2 X信道（XC）和点对点（PTP）信道并存时网络的DOF。研究结论也适合于XC优先于PTP信道的情况。在已知发送端信道状态（CSI）信息的前提下，基于符号扩展模型，利用渐进干扰对齐方法给出了对应的信号处理方案，并证明当n趋于无穷大时，自由度内界可达5/3。利用传播时延模型示范了其可达性。此外，分析了DOF上界。<br>Abstract：Degrees of freedom (DOF) is a spatial multiplexing conception, which was introduced in multiple antenna systems. And it characterizes the utilization efficiency of spatial resource for wireless channels. In the area of cognitive radio, since the primary and secondary networks interfere with each other, the DOF will be reduced. This paper mainly studies the DOF of the network on 2×2 X channel (XC) and point-to-point (PTP) channel which coexist. The result of this paper is also applied to the scenario when the XC has priority over PTP channel. If channel state information (CSI) is available at all transmitters, we propose the signal processing scheme using asymptotic interference alignment approach based on symbol extension model. It is shown that the lower bound of DOF tends to 5/3 when n tends to infinity. A propagation delay model is used to show its achievability. In addition, we analyze the upper bound on the DOF.
%K X信道(XC)
%K 点对点(PTP)信道
%K 信道并存
%K 渐进干扰对齐
%K 自由度(DOF)&lt
%K br&gt
%K X channel (XC)
%K point-to-point (PTP) channel
%K channel coexistence
%K asymptotic interference alignment
%K degrees of freedom (DOF)
%U http://bhxb.buaa.edu.cn/CN/abstract/abstract13758.shtml