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• The chirp-TDR method using the frequency-modulated continuous wave, also known as the chirp signal. The signal arrival time is captured through the pulse compression method. The pulse compression process fully exploits the signal gain generated by the length of the signal in the time domain and the width in the frequency domain. • A prototype is designed and implemented. To further improve the detection sensitivity, the influences of the incident signal and the terminal reflected signal are eliminated through a low noise differential amplifier in the prototype and matching resistance at the terminal, respectively. • The method is verified through experiments. A signal coaxial cable and an XLPE power cable with artificial simulated defects were installed as test specimens. The test results show that the method is feasible and has strong anti-noise ability. • The technology is compared with FDR, which also uses the chirp signal. The proposed method has a performance improvement of more than 10 dB, showing better fault point resolution ability. Diagnosing and locating the high resistance fault (HIF) of XLPE medium voltage cables without causing secondary damage has been a trouble for power maintainers. Among the previous methods proposed by researchers, the frequency domain reflection method has the strongest sensitivity, which still cannot meet the broad dynamic range requirement of HIF detection. This paper proposes a chirp-TDR high resistance fault detection method, which fully taps the signal processing gain of the chirp signal after pulse compression. The method increases the practical detection limit to hundreds of kΩ. A prototype is implemented, and the performance is simulated. The influence of incidence and terminal reflection signals on fault point reflection signal detection is reduced by common mode filtering and access matching impedances. The selected detection signal with 5 ms duration and 20 MHz bandwidth can produce a signal processing gain of 50 dB. A signal coaxial cable and an XLPE power cable with artificial simulated defects were installed as test specimens. The test results show that the method is feasible and has strong anti-noise ability. The technology is compared with FDR, which also uses the chirp signal. The proposed method has a performance improvement of about 12 dB, showing better fault point resolution ability. [ABSTRACT FROM AUTHOR]