RU2356080C1 - System of time synchronisation by wire radio channel - Google Patents

Abstract

FIELD: physics, clock.

SUBSTANCE: invention is designed for application in isolated systems of universal time, in which precise time signals are transmitted for synchronisation of territorially distanced clocks. Invention is aimed at improvement of readings accuracy and synchronisation of distanced clocks. This result is provided by the fact that system of clocks synchronisation by wire radio channel contains master clock, group of distanced clocks. According to invention master clock consists of serially connected program unit of clocks correction and unit of time storage, outlet of which is connected to group of distanced clocks via network interface. Besides device for decoding of precise time signal is additionally introduced, which consists of serially connected unit of radio signal conversion, signal receiver, program unit of signal separation and communication device, outlet of which via communication interface is connected to program unit of clock correction, the first inlet of radio signal conversion unit is connected to radio channel by means of galvanic isolation, and the second inlet - to source of reference voltage, the second inlet of program unit of signal separation is connected to source of clock rate.

EFFECT: improved accuracy of readings and synchronisation of distanced clocks.

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Description

The invention relates to clock synchronization via a wired radio channel and can be used in isolated single time systems in which accurate time signals are transmitted to synchronize geographically separated clocks.

The well-known "Radio-clock synchronization system" (see RF Patent No. 2115946 of 10.26.1995, published in BI No. 20 of 07.20.1998), containing a group of leading hours, a group of remote watches, a central clock, a satellite navigation system and communication lines.

The above system is the closest in technical essence to the claimed system and therefore is selected as a prototype. The disadvantage of the system is the cumbersome design, the inability to use it together with a personal computer (PC) through communication interfaces and to receive accurate time signals via a wired radio channel.

The problem to be solved is the creation of a system for receiving accurate time signals via a wired radio channel in isolated local area networks with the possibility of using it in conjunction with a PC via communication interfaces.

The technical result, the invention is aimed at, is to increase the accuracy of the readings and synchronization of the remote watch.

To achieve the technical result in a time synchronization system over a wired radio channel containing a leading clock, a remote clock group, the new one is that the leading clock consists of a series-connected clock adjustment program unit and a time storage unit, the output of which is connected to the remote clock group via a network interface, an exact time signal decoding device is introduced, consisting of a series-connected radio signal conversion unit, a receiver a signal, a signal isolation program block and a communication device whose output is connected via a communication interface to a clock adjustment program unit, the first input of the radio signal conversion unit is connected to the radio channel by galvanic isolation, and the second input is connected to a reference voltage source, the second input of the signal extraction program unit is connected with a clock source.

Introduction to the time synchronization system over the wire radio channel of the device for decoding the exact time signal allows you to decrypt the signals of the exact time of the wire broadcasting and transmit the value of the exact time to the leading clock.

The drawing shows a block diagram of the claimed system clock synchronization via a wired radio channel.

The system contains a master clock (HF) 1, a group of remote clocks (UCH1-UCHN) 2, a device for decoding an accurate time signal (UDST) 3. The master clock 1 consists of a series-connected clock correction program unit (PBC) 4, a time storage unit ) 5, the output of which is connected to a group of remote clocks 2 through a network interface by means of an exact time transmission unit (BPTC) 6. The exact time signal decoding device 3 consists of series-connected radio signal conversion unit (BPR) 9, a signal receiver (PS) 10, a program unit for extracting the exact time signal (PBWS) 13 and a communication device with an input-output channel (IWS) 14, the output of which through the communication interface is connected to the program unit for adjusting the clock 4 by means of communication (SS) 7. The first input of the radio signal conversion unit 9 is connected to a wired radio channel through galvanic isolation (CGR) 8, and the second input is connected to a reference voltage source (ION) 11. The second input of the program unit for extracting the exact time signal 13 is connected to a clock source (KR) 1 2.

The system operates as follows.

The exact time signal via a wired radio channel is fed to the input of galvanic isolation (GR) 8, made on the basis of the optocoupler. Further, from the output of the GR 8, the signal is fed to the input of the conversion unit of the radio signal 9, made on the basis of the comparator, where it is compared with the signal of the reference voltage source 11, which is a voltage divider. Then, from the output of the radio signal conversion unit 9, the signal is fed to the input of the signal receiver 10, which is a port of the microcontroller. Next, the exact time signal is decrypted by the program unit for extracting the exact time signal 13 according to a certain algorithm and synchronized with the reference signals of the clock source 12 (quartz resonator). Then, from the output of the program unit for extracting the exact time signal 13, the signal is transmitted from the exact time signal decoding device 3 to the driving clock 1 via the communication interface (RS-232) through the communication device with the input-output channel 14. Through the block of the communication means 7 and the communication device with the input-output channel 14, the signal is fed to the input of the program block for adjusting the clock 4, where it is analyzed. Next, the clock correction program unit 4 performs a time correction operation and transmits this value to the time storage unit 5, from the output of which this value is sent to the remote clock group 2 (UCH1-UCHN) through the exact time transmission unit 6 (network adapter via the NTP protocol). Thus, every remote watch UCH1-UCHN (personal computers of users, servers, etc.) receives time values associated with the exact time signals of wired broadcasting.

The galvanic isolation means (GR) 8 is based on the CNY17-2 optocoupler, the radio signal conversion unit is based on the MAX903 comparator, the PIC microcontroller 16F87 series is used as a signal receiver (PS) 10 and program unit (PBWS) 13. A quartz resonator with a frequency of 20 MHz is used as a clock source. The communication device with the input-output channel is based on the MAX232 chip, which allows you to coordinate the signals of the microcontroller and the RS-232 interface of a personal computer.

A prototype was made, which confirmed the operability of the device.

Claims (1)

A time synchronization system via a wired radio channel containing a leading clock, a remote clock group, characterized in that the leading clock consists of a series-connected clock correction program unit and a time storage unit, the output of which is connected to the remote clock group via a network interface, an additional signal decoding device is introduced exact time, consisting of a series-connected radio signal conversion unit, a signal receiver, a software signal isolation unit and a device and communications, the output of which is connected via a communication interface with a software clock adjustment unit, the first input RF signal conversion unit is connected to the radio link by means of galvanic isolation, and the second input - to a source of reference voltage, a second input program signal isolation unit is connected to the source of clock frequency.