基于改进型Duffing振子模型的ZPW-2000移频信号检测方法研究

A New Detecting Method for ZPW-2000 Shift Frequency Signal Based on Improved Duffing Oscillator Model

为了解决传统Duffing振子检测系统中由于待测信号存在初相角而导致可能出现检测盲区的问题,通过分析Duffing方程得到检测盲区所处的范围,提出一种构造相移量的方法实现检测盲区的消除,仿真验证了该方法的可行性。将改进后的Duffing振子检测系统运用于ZPW-2000移频信号的检测,分别给出载频与低频的检测步骤。仿真结果表明,构造相移量的方法可实现对具有任意初相角的ZPW-2000移频信号的检测,在低频检测环节提出一种基于Hilbert变换包络检测的方法,得到了精确的低频信号。将此方法与传统方法进行比较,发现其检测信噪比至少提高30dB。

In order to solve the problem of blind angle caused by initial phase angle of the signals under detection in traditional Duffing oscillator system,by analyzing the Duffing equation to find out the range of blind angle,this paper presented a novel method of constructing phase shift to eliminate the blind angle,which was verified by simulation.The improved Duffing oscillator system was used to detect ZPW-2000 shift frequency signal.The detection steps of carrier frequency and low frequency were given.Simulation results showed that the method of constructing phase shift could achieve the detection of ZPW-2000 shift frequency with arbitrary initial phase angle.In low frequency detection,Hilbert transform-based envelop detection method was proposed to obtain the accurate low frequency signal.As a result,the signal-to-noise ratio can be enhanced by 30 dB at least based on the improved method compared with traditional method.