Abstract:

The civil aviation communication system undertakes key flight command， dispatching， and ground-to-air communications in the Very High Frequency （VHF） band. Therefore， the interference within this spectral environment is of significant concern. In response to the potential electromagnetic interference from electrified railways with civil aviation mobile services in the VHF band， this paper proposes a method for analyzing electromagnetic emissions when trains pass through ordinary points and electrical phase separation based on measured frequency-domain data. Firstly， according to the international standard CISPR16-1， the electromagnetic emission data of the train is tested and converted to result of the 10-meter method. Then a logarithmic regression equation about frequency is used to fit the data. Finally， to enhance the ability of the regression equation to describe the random data of electric field generated by the train， the support vector regression method based on Bayesian optimization is used to solve the coefficients of the regression equation. The results show that within the frequency band of aviation mobile services， the proposed method for describing the electromagnetic emissions generated by trains passing through ordinary points and electrical phase positions increases the decidable coefficients from 0.84 and 0.82 to 0.98 and 0.94， respectively， compared to the traditional least squares method， making it more suitable for solving regression equation coefficients. The results also show that the proposed method has strong robustness in handling the randomness of measured data， providing theoretical support for the analysis of electromagnetic interference characteristics and interference suppression design and decision-making in civil aviation.

Key words: pantograph catenary arc, civil aviation, electromagnetic emission, high speed railway, electromagnetic compatibility