一种基于射频光传输技术的同址干扰抑制方法

Co-site interference suppression method based on radio frequency optical transmission technology

在无线信道系统中,同址干扰会导致接收机的接收灵敏度下降。基于微波光子技术,根据强度调制直接检测(IMDD)光链路的非线性特性,提出了一种射频同址干扰抑制方法。首先,建立了IMDD光链路输出功率的数学模型,并用数学方程描述干扰信号和有用信号的输出功率大小,通过令干扰信号输出为零时求得方程的解,获得干扰抑制的条件。然后,通过Matlab定量计算得到链路中干扰信号和有用信号的输出功率随输入干扰信号功率变化的曲线,得出干扰抑制的功率输出点,并分析了半波电压大小对干扰抑制的影响。实验结果表明:该方法的抑制比可达到-64.5 dB,且有用信号的输出功率只损失6.4 dBm,具有优异的干扰信号抑制能力。

In wireless channel system,co-site interferencewill cause the receiver's reception sensitivity to decline.Based on microwave photonics technology,according to the nonlinear characteristics of intensity modulated direct detection(IMDD)optical link,a radio frequency co-site interference suppression method is proposed.Firstly,the mathematical model of the output power of IMDD optical link is established,and the output power of interference signal and useful signal is described by mathematical equation.By making the output of interference signal zero,the solution of the equation is obtained,and the conditions of interference suppression are obtained.Then,through Matlab quantitative calculation,the curve of the output power of interference signals and useful signals in the link changing with the input interference signal power is obtained,the power output point of interference suppression is obtained,and the influence of half wave voltage on interference suppression is analyzed.The experimental results show that the suppression ratio of this method can reach-64.5 dB,and the output power of the useful signal is only lost by 6.4 dBm,which has excellent interference signal suppression ability.