Frequency domain reflection (FDR) is a powerful method for detecting impedance discontinuity points such as local defects and faults in power cables. However, due to signal attenuation, the reflection formed by faults and defects will weaken with increasing distance, which poses a significant challenge for achieving precise cable detection. To address this issue, this article proposes a attenuation compensation technology based on FDR, aiming to compensate for signal attenuation and improve detection accuracy and sensitivity. A cable fault simulation model and experimental platform have been established to verify the effectiveness of this method. The results show that the positioning error of this method is less than 0.5%, and the average error of transmission parameter recovery is less than 5%, verifying the effectiveness of this method