Research on Reradiation Interference Suppression of Transmission Tower Based on Characteristic Mode Theory

As a large metal conductor, transmission line tower can cause interference to nearby radio stations. In order to suppress the electromagnetic environment problems caused by transmission line towers, this paper analyzes the body structure of transmission line towers by applying the characteristic mode theory (CMT), and identifies the induced current distribution on the tower body is identified as the dominant contributor to reradiation interference. Then, the orthogonal test method is used to optimize the parameters such as the number of detuner installations, the detuner installation position and the detuner internal capacitor installation position to obtain the optimal combination of detuner parameters. Finally, the optimal model of the detuner is compared with the initial transmission line model. The results of the study show that 41.91% of the reradiation interference from transmission line towers in the medium-wave broadcasting band is reduced by optimizing the detuner parameter settings, which achieves the purpose of suppressing the reradiation interference from transmission towers. The proposed approach provides a practical suppression strategy for existing trans mission towers and establishes a theoretical foundation for future interference mitigation research.