Frequency shifting signal frequency meter for automatic occlusion training equipment

Abstract

A frequency shifting signal frequency meter used for automatic block training equipment, relating to an electronic measuring instrument, including a main rail signal conditioning module, a signal pre-selection module, a small rail signal conditioning module, a signal gating module, a central control module, etc. ; The input end of the main rail signal conditioning module is used to input the frequency shift signal, the output end is connected with the input end of the signal pre-selection module and the central control module, the output end of the signal pre-selection module is connected with the input end of the small rail signal conditioning module, and the small rail The output end of the signal conditioning module is connected to the signal gating module, the output end of the signal gating module is connected to the input end of the central control module, and the output end of the central control module is respectively connected to the signal pre-gating module, the signal gating module and the display module. The invention has the function of measuring the carrier frequency of the main rail signal and the carrier frequency of the minor rail signal, has stable and reliable performance, low cost, convenient use and maintenance, improves teaching efficiency, and can meet the needs of professional training of railway communication signals in colleges and universities.

Description

technical field [0001] The invention relates to an electronic measuring instrument, in particular to a frequency shifting signal frequency meter used for automatic block training equipment. Background technique [0002] In the automatic block training, the signal equipment receives the frequency-shifted signal through the track circuit. The frequency-shifted signal is mixed with the main rail signal and the small rail signal. The effective value of the voltage of the main rail signal is far greater than the effective value of the voltage of the small rail signal. The two are superimposed on the cable to synthesize a frequency shift signal. The main track signal and the small track signal are low frequency signals, which are modulated to a higher frequency sine wave carrier frequency during the communication process. When the front track is occupied by a train, the corresponding small track signal will be short-circuited, and at this time the signal equipment will issue corr...

AI Technical Summary

Problems solved by technology

At present, this type of test instrument is designed with FPGA+DSP, and the price is extremely high. The price of each record sheet generally costs 40,000 yuan, and many other functions are used very rarely in practical training. To a certain extent, The input cost of this kind of teaching resources is very high, but the utilization rate is very low, so this kind of instrument cannot be popularized and applied in the training room of railway-related majors in colleges and universities.

Therefore, many school-related training rooms are only equipped with a small number of such instruments, and some training rooms even use oscilloscopes to measure the frequency of frequency-shifted signals, which directly affects the efficiency and effect of automatic block training

Some products use program-controlled filter design to filter and amplify the carrier frequency of all frequency-shifted signals. This solution has poor effect and unstable performance.

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