Long-line shielding cable transfer impedance measurement system and method based on wavelet denoising

The invention discloses a long-line shielding cable transfer impedance measurement method based on wavelet denoising. The method comprises the steps: determining the impedance of an inner loop and theimpedance of an outer loop according to the reflection mechanism of a transmission line, and designing an impedance matching network; making an oscilloscope and the impedance matching network connected, the impedance matching network and a tested shielding cable connected, a reference conductor plane and the impedance matching network connected, and an oscillating circuit and a signal pulse transmitter connected, making such parts arranged beside the tested shielding cable, and fixing the tested shielding cable by a clamp; generating a high-frequency excitation signal through a signal pulse emitter, and forming a simulated external electromagnetic wave interference source through an oscillating circuit; connecting the tail end of the tested cable to the oscilloscope, and receiving and reading a response signal of