Research and Realization of High Stability Fiber Bragg Grating Track Axle Counting System

Abstract:
At present, track circuit and electromagnetic axle counter are mainly used in track occupancy monitoring technology. However, due to the poor anti-corrosion and anti-electromagnetic interference ability of electrical sensing elements, especially in thunderstorm weather, their working reliability is greatly reduced. Fiber Bragg grating sensing technology uses optical signals to sense and transmit environmental information. In essence, it has strong anti-corrosion and anti-electromagnetic interference ability, so it makes up for the defects of the current electric track axle counting scheme. Therefore, this research uses the advantages of fiber Bragg grating sensing technology, adopts edge filter demodulation method and embedded technology to realize a high stability fiber Bragg grating track axle counting system. This paper mainly studies the temperature characteristics of linear optical filter, simulates and verifies its temperature drift characteristics, and designs a temperature compensation algorithm to control its temperature wavelength drift within 10pm. For the loosening / falling off function of the axle counter and monitoring sensor of the system, the wavelength drift of 10pm will not affect it, so the system has high temperature stability.