Research on noise reduction of weak signals in grounding reliability testing of aircraft cable shield

Abstract

There are some signal sampling processes during the testing process of aircraft cable shield grounding reliability, and the current and voltage signals obtained are very weak. Also there exists some noise components which is independent of the signal to be analyzed due to the acquisition environment and the instruments used. If the signals are analyzed directly without filtering the noisy signal first, it will affect the final detection accuracy of the instrument. In this paper, a simulation model on the cable shield for aircraft loop impedance test system was established and analyzed deeply. The method of combined de-noising of EMD(Empirical Mode Decomposition) and wavelet transform was introduced. The comparing results between experimental data and simulation results show that the de-noising effect of this method is satisfying and reliable and can be utilized in application engineering field.