Cable defect positioning method, system and equipment based on virtual impedance matching

The invention discloses a cable defect positioning method, system and equipment based on virtual impedance matching, and the method comprises the steps: determining a head end reflection coefficient spectrum of a cable head end according to a virtual time domain signal and an actually measured cable reflection coefficient spectrum actually measured through a network analyzer; according to the cable characteristic impedance and the head end reflection coefficient spectrum, determining the equivalent impedance of a signal connection line of the network analyzer; eliminating the equivalent impedance of the signal connecting line in the head end input impedance of the head end of the cable to obtain corrected head end input impedance after correction; and correcting the actually measured cable reflection coefficient spectrum according to the corrected head end input impedance to obtain a corrected cable reflection coefficient spectrum, and positioning the defect of the cable based on the corrected cable reflectio