RU2811914C1 - Method for automatically turning on radio transmitting device - Google Patents

Abstract

FIELD: electrical radio engineering.

SUBSTANCE: systems of VLF and ELF radio transmitting devices can be used in radio transmitters. The method for automatically turning on a radio transmitting device additionally includes the microcontroller controlling the functional units of the device for automatically turning on the radio transmitting device, measuring the durations of positive and negative pulses when a starting signal and distortion are received at the input of the device for automatically turning on the radio transmitting device, as well as comparing them with constants recorded in the microcontroller memory and checking their equality with each other within the established tolerance. The automatic switching device for the radio transmitting device analyzes both the shapes and frequencies of the starting signals. The number of comparison cycles is set from the control device. When the shape and frequency of the input signals match, the microcontroller generates a signal that is sent from the microcontroller output to the information display and timer, as a result of which the timer removes the locking signal, and the actuator unlocks the radio transmitting device. A level converter with galvanic isolation transmits an information signal between electrical circuits. The constants recorded in the microcontroller memory correspond to three speeds of the input signals. The actuator is made in the form of an electromagnetic relay, the “dry” contacts of which are included in the unlocking circuit of the radio transmitting device.

EFFECT: improving the quality of communication due to timely unlocking of the radio transmitting device, which guarantees the transmission of information messages without loss.

1 cl, 3 dwg

Description

The invention relates to electrical and radio engineering, namely to systems for automatically switching on VHF and VLF radio transmitting devices and can be used in radio transmitters.

A well-known ELF radio transmitter is the product ZHYa1.200.292 P34. Equipment for generating excitation signals developed by NPO "Comintern", Leningrad, 1991. The radio transmitter consists of an exciter, a power amplifier and a control unit.

A complex of extremely low and ultra-low frequencies for geophysical research is known” (RF patent No. 2188439, MKI G01V 3/12, 2002). This device consists of several identical generators operating on separate antennas, a single master oscillator and a digital receiving device.

The prototype of the proposed device is an VHF radio transmitter. The radio transmitter consists of an exciter, a power amplifier and a control unit and is designed to transmit: control signals and messages from control points to mobile and stationary correspondents; signals of the state system of uniform time and reference frequencies. The radio transmitter provides signal transmission in amplitude telegraphy (AT), frequency telegraphy (FT) and relative phase telegraphy (RPT) modes in the ultra-long wave radio wave range with an output power of 1000 kW. In the VSD transmitter, the radio transmitting device is automatically turned on, which includes an analysis of the shape and frequency of the trigger signals arriving at the input and their comparison with compliance with the specified parameters that unlock the radio transmitting device.

[flotprom.ru>Catalogue ELEMENT_ID=83190 radio transmitter "GOLIATH - 2MK"].

The disadvantage of both the analogue and the prototype is that they do not have the ability to timely unlock the radio transmitting device during short starting signals, which leads to the loss of part of the beginning of the information message.

The purpose of the invention is to improve the quality of communication due to timely unlocking of the radio transmitting device, which guarantees the transmission of information messages without loss.

This goal is achieved by the fact that the method for automatically turning on a radio transmitting device, including analyzing the shape and frequency of the starting signals arriving at the input of the device for automatically turning on the radio transmitting device and comparing them with the specified parameters, characterized in that the microcontroller controls the functional units of the device for automatically turning on the radio transmitting device, measuring durations of positive and negative pulses when a trigger signal and distortion arrive at the input, as well as comparing them with constants recorded in the microcontroller memory corresponding to the three speeds of input signals, and checking their equality with each other within the established tolerance, while analyzing both the shape and and frequency of starting signals, the number of comparison cycles is set from the control device, and if the shape and frequency of the signals arriving at the input match, the microcontroller generates a signal that is sent from the output of the microcontroller to the information display and timer, as a result of which the timer removes the locking signal, and the actuator, made in the form of an electromagnetic relay, the “dry” contacts of which are included in the unlocking circuit of the radio transmitting device, unlocks it, while a level converter with galvanic isolation transmits an information signal between electrical circuits.

A functional diagram of a device for implementing a method for automatically turning on a radio transmitting device, where the following notations are adopted, is shown in Fig.1.

It contains:

1 - microcontroller type AT89S52;

2 - information display;

3 - control device (keyboard);

4 - level converter with galvanic isolation;

5 - timer;

6 - actuator.

The device for automatically turning on the radio transmitting device (hereinafter referred to as UAVRPDU) is designed to automatically unlock the radio transmitting device (RPdU) when operating on a radio line. The structure of the message flow is shown in Fig.2.

Trigger signals are transmitted by bipolar rectangular pulses (meander) with an amplitude of ±20 V, the frequency of which can range from 15 to 25 Hz, which corresponds to a transmission speed of 30 to 50 Baud.

The automatic switching device for the radio transmitting device analyzes both the shape and frequency of the trigger signals. If the shape and frequency of the signals arriving at the input correspond to the specified parameters, the automatic switching device unlocks the remote control.

To prevent the RPDU from locking during pauses between messages in the stream (time T2 in Fig. 2), the UAVRPDU delays when the executive circuit is turned off. If during the delay time not a single pulse arrives at the input of the UAVRPdU, then the RPdU will be locked.

Main technical characteristics of UAVRPdU.

The number of 3 operating speeds of trigger signals specified from the control device (keyboard), which are simultaneously analyzed by the UAVRPDU - 3. The speed range of trigger signals is 26÷160 Baud (13÷80 Hz).

The number of measuring cycles (checks) of the trigger signal specified from the control device (keyboard) is 3÷15.

Trigger analysis time at 26 baud:

- 0.26 s with 3 measuring cycles;

- 1.19 s with 15 measuring cycles. Electrical parameters of the output signal:

- logic “1” voltage plus 20÷27 V;

- logical voltage “0” minus 20÷27 V;

- input resistance - 4.7 kOhm.

Tolerance for frequency and distortion of input signals 1÷20% (set by software).

The delay time for turning off the executive circuit is 1.3 s. Figure 3 shows the time parameters of the UAVRPdU operation. The device works as follows.

From the moment the trigger signals arrive at the input of the UAVRPdU during the time T _an (Fig. 3), the device analyzes their speed and distortion. If they correspond to the set values, the RPdU is unlocked. If the pauses between messages do not exceed the shutdown delay time T _set = 1.3 s, the RPdU is not locked. After the end of messages, after a time of 1.3 s, the RPdU is locked.

The basis of the device is a microcontroller type AT89C52 1, which performs the necessary actions according to a given program. When a trigger signal is received at the input, the microcontroller begins to measure the durations of positive and negative pulses and compares them with constants recorded in the microcontroller’s memory. The percentage tolerance on the pulse duration can be changed programmatically in the range from 1 to 20%. At the same time, the microcontroller makes a comparison with constants that, by default, correspond to 3 input signal speeds of 36, 50 and 100 Baud.

The microcontroller generates a signal to turn on the RPDU if two conditions are met: the durations of the positive and negative pulses correspond to the specified speed and are equal to each other within the established tolerance. The number of comparison cycles can be set from the control device (keyboard) 3 in the range from 3 to 15. Increasing the number of comparison cycles increases the accuracy, but at the same time the time T _an increases (see Fig. 3). Each of the 3 operating speeds can also be set from the control device (keyboard) 3. At the moment the signal is given to turn on the RPDU, the microcontroller calculates the speed using the pulse duration with an accuracy of 0.1 Baud and displays the information on display 2.

The device also has the ability to measure the speed of an unknown signal entering the input. When you press the “MEAS+” button, the speed is calculated from the duration of positive pulses, and when you press “MEAS-” - negative ones. Thus, having determined the speed of the unknown trigger signal, you can enter this value into one of the operating speeds.

Level converter with galvanic isolation 4 transmits an information signal between electrical circuits that do not have direct electrical contact between them in order to reduce interference, for contactless control and to protect equipment from damage and people from electric shock.

The signal to unlock the RPDU from the output of the microcontroller is sent to timer 5, which, if not a single pulse is received at the input within 1.3 s, then removes the unlocking signal and the actuator 6 locks the RPDU.

On the front panel of the device there is an “Operation” LED, signaling the activation of actuator 6, as well as an “Input” LED, indicating the presence of a signal at the device input.

An electromagnetic relay is used as an actuator 6, the “dry” contacts of which are included in the RPdU unlocking circuit. The device is powered from an unstabilized DC source with voltages of 9 and 24 V and consumption currents of 0.2 and 0.02 A, respectively.

This device has been in operation for 3 years at the SDV RPDU and has proven itself to be reliable and easy to use. Thanks to its flexibility and great functionality, the efficiency of work and the quality of communication have increased. In particular, with short starting signals, the RPdU is timely unlocked, which ensures that the beginning of the information message is not lost. Thus, due to the timely start of operation of the radio transmitting device, the quality of communication is improved.

Claims (1)

A method for automatically turning on a radio transmitting device, including analyzing the shape and frequency of the starting signals arriving at the input of the device for automatically turning on the radio transmitting device and comparing them with specified parameters, characterized in that the microcontroller controls the functional units of the device for automatically turning on the radio transmitting device, measuring the durations of positive and negative pulses at arrival of a trigger signal and distortion at the input, as well as comparing them with the constants recorded in the microcontroller memory, corresponding to the three speeds of the input signals, and checking their equality with each other within the established tolerance, while analyzing both the shape and frequency of the trigger signals, with control device, the number of comparison cycles is set, and if the shape and frequency of the input signals match, the microcontroller generates a signal that is sent from the microcontroller output to the information display and timer, as a result of which the timer removes the locking signal, and the actuator, made in the form of an electromagnetic relay, The “dry” contacts of which are included in the unlocking circuit of the radio transmitting device unlock it, while the level converter with galvanic isolation transmits the information signal between the electrical circuits.

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