Signal processing method for phase-sensitive track circuit receiver

Abstract

The invention discloses a signal processing method for a phase-sensitive track circuit receiver and relates to the signal processing technology. The signal processing method includes the following steps that firstly, A / D conversion is conducted on a track signal and a local signal, and a digital track signal SG (t) and a digital local signal SJ (t)' are generated; secondly, discrete Fourier transform is conducted on the track signal and the local signal, and a track signal sine component aG (k), a track signal cosine component bG (k), a local signal sine component aJ (k) and a local signal cosine component bJ (k) are obtained; thirdly, a folding algorithm and an iterative algorithm are used for calculating track / local signal amplitudes and phases respectively; fourthly, calculation results of the iterative algorithm and the folding algorithm serve as the basis, a comparison value (see it in the specifications) is calculated through a threshold function, if the comparison value (see it in the specifications) obtained with the calculation result of the folding algorithm as the basis and the comparison value (see it in the specifications) obtained with the calculation result of the iterative algorithm as the basis are both larger than or equal to a preset relay energized threshold, a relay is energized, and if the comparison value (see it in the specifications) obtained with the calculation result of the folding algorithm as the basis and the comparison value (see it in the specifications) obtained with the calculation result of the iterative algorithm as the basis are both smaller than or equal to a preset relay falling threshold, the relay falls. The signal processing method is high in processing precision and processing speed.

Description

Technical field [0001] The present invention relates to signal processing technology. Background technique [0002] Digitization is an important direction for the development of railway signal control systems. Digital signal processing technology emerged with the development of computer and information science and has been developing rapidly. In recent years, digital signal processing has been widely used in communications, automation and other fields. With the development of electronic technology, the receiving end of the 25Hz phase-sensitive track circuit is gradually adopting electronic technology, replacing the mechanical action of the previous two-dimensional two-position relay, completely solving the original relay contact jam, the ability to resist electrical interference is not strong, and the return coefficient is low. And other issues, the receiving impedance and receiving sensitivity of the original relay are the same, which improves the safety and reliability. [000...

AI Technical Summary

Problems solved by technology

[0003] At present, in addition to using mechanical binary two-position relays to check the track occupancy, there are also phase-sensitive receivers developed based on 51 single-chip microcomputers. The binary two-position relays are purely mechanical in action, and have contact jamming and weak anti-electrical interference capabilities. , the return coefficient is low, etc., and the phase-sensitive receiver developed based on the 51 single-chip microcomputer, due to the low data processing capability, the processing method can only use the look-up table method, the data processing is simple, and the error range is large.

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