基于频率正交时间反演的空间聚焦虚拟覆盖方法研究

Research on space focusing virtual coverage based on orthogonal frequency time reversal method

针对超密集无线网中的信息泄露和传输覆盖效率问题,提出了基于频率正交时间反演的虚拟覆盖方法。首先,以正交子载波区分各信道,降低相关度;其次,进行时间反演,让各目标信号在目的用户附近空间聚焦;然后,研究推导出覆盖范围与信号干扰噪声比理论表达式并进行论证;最后,在确保用户覆盖需求的基础上,无关用户的覆盖范围缩小,形成了虚拟覆盖。仿真表明,在不增加功率和天线情况下,虚拟覆盖增加了接收信号难度,提升了可靠传输的安全速率和系统容量。

To solve the problem of information leakage and coverage efficiency in ultra-dense wireless network,the orthogonal frequency-time reversal virtual coverage scheme was proposed.At first,different wireless reversal channels with lower correlation were distinguished by orthogonal carries.Next,after time reversal,the space focusing of each target signal was realized around the terminal.Then,theoretical expressions of the signal coverage and the signal- interference-to-noise ratio were derived and proved.Ultimately,the virtual coverage was shaped,meeting the requirements of users.The coverage of unrelated user not belonging to system was reduced.The results show that those unrelated users are difficult to receive the target signal because of virtual coverage.In addition,the system has higher capacity and security rate of reliable transmission without any more power or antennas.