基于调制信号的宽带无源互调测试系统

A new wideband passive intermodulation test system based on modulated signal

无源互调是衡量移动通信设备质量的关键指标。传统无源互调测量方案采用CW信号近似网络中的实际信号作为激励源,但随着移动通信不断向宽带化发展,沿用CW信号测试已不能完全反映网络中实际存在的互调问题。为此,提出基于真实调制信号的宽带互调测试系统方案。在解决宽带信号峰均比压缩、弱信号检测等技术难题的基础上,成功研发宽带互调测试系统样机及配套操作软件,该系统目前已应用于实验室的日常测试任务并取得了良好效果。

Passive intermodulation is a key indicator in performance evaluation of communication equipment.In traditional test scheme,continuous wave is adopted as the source signal.However,it becomes unreasonable as the bandwidth of real modulated signal increases in communication network,and more and more network faults caused by passive intermodulation cannot be detected.In this paper,a new wideband passive intermodulation test scheme based on modulated signal is proposed.After tackling the problems of peak-to-average power ratio reduction and weak signal detection,the hardware test system is realized and has already been used in practice.