A method for testing the reflection response of two impedance discontinuities on a transmission line

Abstract

The present invention proposes a test method for the reflection response of two impedance discontinuities on the transmission line. Firstly, time-domain transformation is performed on the measurement results in the frequency domain to obtain the time-domain responses of the two impedance discontinuities; next, the time-domain The results are gated separately, and converted back to the frequency domain after gating; then, for each gating result, an equation is established in the frequency domain according to the signal flow direction, and each equation includes the reflection coefficient of the impedance discontinuity point and the transmission line of each section The transmission coefficient; finally, the simultaneous equations are solved to obtain the reflection coefficient of the impedance discontinuity. Compared with the direct time-domain measurement method, the test method of the present invention can eliminate the influence of mutual reflection at impedance discontinuity points, obtain the reflection coefficient at the position where the reflection occurs, and the accuracy is obviously improved; and the transmission characteristics of the transmission line can be obtained at the same time.

Description

technical field [0001] The invention relates to the technical field of testing, in particular to a testing method for reflection responses of two impedance discontinuous points on a transmission line. Background technique [0002] The vector network analyzer is an instrument that obtains the characteristic parameters of the device under test by generating a sweep frequency excitation signal, stimulating the device under test and receiving its scattered signal. When measuring the frequency response of a transmission line, if there is an impedance mismatch point inside the transmission line, reflections will occur. What you see in the frequency domain is the effect of the superposition of reflections at each frequency point, and it is the superposition response of all reflections on the entire transmission line, but it cannot point out the location where the reflection occurs. [0003] The vector network analyzer has a time-domain measurement function. After the frequency-dom...

AI Technical Summary

Problems solved by technology

[0006] When there are two impedance discontinuities on the transmission line, the reflected signals will block each other, and the loss of the transmission line itself will also affect the signal, so that the signal measured by the instrument is not the real incident and reflected signal of the reflection point. The actual impedance characteristics of continuous points are quite different, and the accuracy of the test results is low

Images