Efficient rail circuits diagnostics technologies: modeling of wideband signal propagation and loss minimization

This article discusses a modern method for diagnosing track circuits using broadband signals. The relevance of this research stems from significant shortcomings of traditional track circuits, such as low information content, strong dependence on ballast condition, and high operating costs, which lead to significant economic losses and risks to traffic safety. The proposed approach using broadband signals enables continuous monitoring of track conditions in real time, precisely localizing defects such as breaks, current leaks, insulation deterioration, and microcracks, which is impossible using traditional methods. This not only improves traffic safety but also significantly reduces the number of false alarms. The paper presents a detailed mathematical model of broadband signal propagation, taking into account key attenuation factors: the effect of current leakage through ballast, sleepers, and track connections. A comprehensive analysis of the signal's frequency characteristics was conducted, including a study of the skin effect in rails and the dependence of the complex ballast impedance on external conditions such as humidity and temperature. To minimize signal loss, a comprehensive approach based on adaptive frequency range optimization and data processing algorithms was proposed. The study focuses on the principle of matched filtering, which maximizes the signal-to-noise ratio at the filter output through effective signal compression and intelligent parameter selection. A structural diagram of the diagnostic system with a detailed description of its functional components was developed and presented. The study results demonstrate that the implementation of a monitoring system based on broadband signals enables continuous monitoring of infrastructure conditions without interrupting service, significantly improving the accuracy and speed of defect localization. Practical implementation of the developed method can significantly reduce operating costs and improve the overall reliability, safety, and throughput of rail transport.