Field intensity test start device

Abstract

The invention relates to a field intensity test starter comprising a control unit, an operation display unit and a channel machine unit. The control unit is formed by connecting a CPU, a first filter adjusting circuit, a second filter adjusting circuit, an operational amplifier and a power conversion circuit. The CPU of the field intensity test starter generates 218.1Hz sub audio and a FFSK signaling containing site location and emission time, and the sub audio and the signaling are emitted through a PTT control channel machine. The FFSK and the 218.1Hz signals are generated inside a program control CPU, the FFSK signal is filtered and shaped by an active filter C, a digital potentiometer A adjusts the amplitude of the FFSK signal, the 218.1Hz sub audio signal is filtered and shaped by an active filter D, a digital potentiometer B adjusts the amplitude of the 218.1Hz sub audio signal, and the FFSK signal and the 218.1Hz sub audio signal are further adjusted by the operational amplifier. The field intensity test start device has the following beneficial effects: station radios along the way can emit field intensity test carriers under the control of the device at a specified time, and the device can be compatible with standard B and C systems, is simple to operate, convenient to carry and low in cost, and can satisfy field needs.

Description

technical field [0001] The invention relates to a field strength test starting device, in particular to a field strength test starting device for a 450MHz railway wireless train dispatching system. Background technique [0002] The railway wireless train dispatching communication system mainly completes the communication functions of the big triangle (communication between the dispatcher, station, locomotive / car captain) and the communication function of the small triangle (communication between the station attendant, locomotive / car captain), which is to ensure the safety of railway traffic Foundation. To ensure the normal operation of the railway communication system, the field strength test is an essential link. Field strength is the abbreviation of electric field strength, which is the magnitude of the electric signal induced by the antenna at a certain point in space to characterize the electric field strength at that point. When optimizing the signal in a certain area...

AI Technical Summary

Problems solved by technology

There are very high requirements for the station platform to transmit the field strength test carrier at the specified time. It can neither affect the normal call of the station platform, but also transmit at the specified time. It is also necessary for each station along the line to be equipped with testers to control the station to enter the test state. It takes a lot of manpower and material resources

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