The ultra-high frequency(UHF)-based partial discharge(PD)detection technology for gas-insulated switchgear(GIS)has been widely applied due to its high sensitivity and real-time monitoring capability.However

long-term service may cause antenna corrosion in UHF sensors

leading to degradation of their anti-interference performance.To ensure the reliability of monitoring data

on-site calibration of sensors under noisy conditions is required.This study first analyzes the time-frequency characteristics of white noise received by UHF sensors in GIS environments.By leveraging the transceiver reciprocity of sensors

a noise reconstruction method based on external sensors is proposed to simulate on-site white noise.Simulation models of both standard and degraded sensors are then established to quantify the effects of antenna corrosion on performance parameters such as echo impedance(S11)and voltage standing wave ratio(VSWR).Finally

both sensor models are coupled into GIS handholes for comparative simulation analysis.Simulation results show that antenna corrosion shifts the resonant frequency

reduces PD signal power by 55.27%

and increases noise power by 64.11%.Consequently

the signal-to-noise ratio(SNR)decreases from -9.70 dB to -15.34 dB

with evident waveform distortion indouble-exponential PD pulses.The findings provide a theoretical reference for on-site calibration of UHF sensors in noisy environments.