一种抑制通信基站无源互调干扰的算法

An Algorithm for Suppressing Passive Intermodulation Interference of Communication Basestation

分析通信基站无源互调干扰信号产生的原因及影响,给出了高阶无源互调信号频率的计算公式。结合4G LTE频段2的发射频率带宽和接收频率带宽,仿真了两个单音频率信号在3种频率间隔下产生的互调信号,并进一步仿真了LTE 10 MHz宽带信号的互调信号对接收系统的影响,提出了一种基于发射系统中频数字信号模拟产生无源互调基信号的方法。利用最小二乘估计算法计算接收系统含有的无源互调基信号的幅度和相位值,并进行相消处理。最后,给出了实测数据的仿真结果,验证了方法的可行性。

The causes and effects of passive intermodulation interference signals generated by communication basestations are analyzed,and the calculation formulas of high-order passive intermodulation signal frequencies given.According to the transmission frequency bandwidth and receiving frequency bandwidth of 4G LTE bands 2,the intermodulation signals generated by two single-tone frequency signals at three frequency intervals are simulated.Furthermore,the effects of the intermodulation signals of LTE 10MHz broadband signals on the receiving system is also simulated.A passive intermodulation base signal generation method based on middle frequency digital signal in transmitting system is proposed.The amplitude and phase of passive intermodulation base signal in receiving system are calculated by LS(least square)estimation algorithm,and the passive intermodulation in receiving system is cancelled.Finally,the simulation results of the measured data are given,and the feasibility of this method verified.