RU232294U1 - TIME SERVER - Google Patents

Abstract

The utility model relates to time synchronization means and can be used in devices that synchronize geographically dispersed secondary clocks relative to primary clocks. The task that the utility model is aimed at solving is to create a compact, simple, energy-efficient synchronization device that does not have redundant blocks, and the processing and formation of synchronization signals is performed by hardware. The technical result of the utility model is an increase in energy efficiency and a simplification of the design due to the elimination of power supplies and interfaces for receiving input synchronization signals, as well as related logical and software blocks and microcircuits for processing them. The obtained result is achieved in that a time server is proposed, comprising a unit for receiving, processing and filtering GNSS signals, a real-time clock and reference generator unit, a unit for receiving and generating PTP packets, an SPF interface unit, wherein the unit for receiving, processing and filtering GNSS signals, configured to digitally filter phase noise of the 1PPS signal with subsequent generation of a stable frequency based on it, is connected by its output to the first input of a hardware-implemented unit of the real-time clock and reference generator, the second output of which is connected to the first input of the unit for receiving and generating PTP packets, implemented in the form of a set of machines with a fixed response time independent of the load, the second output of which is connected to the second input of the real-time clock unit for implementing synchronization modes from an external grandmaster, and the first output is connected to an SFP interface unit, the first output of which is connected to the second input of the unit for receiving and generating PTP packets for ensuring bidirectional data transmission, characterized in that the time server is implemented in the form of a module placed in the SFP port of a switch/router.

Description

The utility model relates to time synchronization means and can be used in devices that synchronize geographically dispersed secondary clocks relative to primary clocks.

A device for synchronizing clocks is known (RU 166018), comprising a primary clock, a receiver of signals from a global navigation satellite system, a receiver of reference signals of frequency and time of ground stations, and a central processor connected to them via data exchange channels, characterized in that the device additionally comprises an optical network port, a generator of messages transmitted to a secondary clock, connected by its output to the input of the optical network port, and a generator of messages received from the secondary clock, connected by its input to the output of the optical network port, wherein the output of the primary clock is connected to the first input of the generator of messages transmitted to the secondary clock and the first input of the central processor, the second input of which is connected to the output of the generator of messages received from the secondary clock, and the output is connected to the second input of the generator of messages transmitted to the secondary clock.

A device for synchronizing clocks is known (RU 175803), comprising a primary clock and a central processor connected by an information exchange bus, a generator of messages transmitted to a secondary clock connected to the primary clock, and an optical network port connected to the generator of messages transmitted to the secondary clock and the generator of messages received from the secondary clock, characterized in that the generator of messages transmitted to the secondary clock, the generator of messages received from the secondary clock and the optical network port contain, respectively, N output generators, N input generators and N transceiver optoelectronic elements, where N>1, wherein the signal inputs of the output generators of the generator of messages transmitted to the secondary clock are connected to the signal output of the primary clock, the information inputs of the output generators of the generator of messages transmitted to the secondary clock are connected to the corresponding outputs of the router, the input of which is connected to the information output of the central processor, and the output .... the secondary message clocks are connected to the transmitting inputs of the corresponding transceiving optoelectronic elements of the optical network port, while the receiving outputs of the optoelectronic elements of the optical network port are connected to the signal inputs of the corresponding input forming elements of the former of the messages received from the secondary clock, the time fixing inputs of which are connected to the output of the time signals of the central processor, and the outputs are connected to the corresponding inputs of the feedback message storage and transmission unit, the output of which is connected to the input of the feedback signals of the central processor.

It is known (RU 209989) A device for synchronizing clocks, comprising a primary clock, a receiver of global navigation satellite system signals, a receiver of reference frequency and time signals of ground stations, as well as a central processor connected to them via data exchange channels, a generator of messages transmitted to a secondary clock and a generator of messages received from the secondary clock, wherein the output of the primary clock is connected to the first input of the central processor and the first input of the generator of messages transmitted to the secondary clock, the output of the generator of messages received from the secondary clock is connected to the second input of the central processor, the first output of which is connected to the second input of the generator of messages transmitted to a remote clock, characterized in that the output of the primary clock is also connected to the first input of the generator of messages received from the secondary clock, a mode generator, a VHF transmitter, an antenna-feeder device and a VHF receiver, the output of which is connected to the second input of the generator of messages received from the secondary clock, are also introduced into the device, and the input of the VHF transmitter is connected to the output of the generator of messages transmitted to the secondary clock, while the output of the mode generator is connected to the third input of the central processor and to the corresponding third inputs of the central processor and generators of messages transmitted to the secondary clock and received from the secondary clock, and the second output of the central processor is connected to the input of the mode generator.

The disadvantages of the above-mentioned devices include the use of a central processor to process precise time signals, since software synchronization reduces the speed of processing incoming signals and the accuracy of synchronization.

In addition, the above devices have limited functionality.

Thus, the device according to patent RU 209989 is used only for synchronizing secondary devices that provide reception and transmission of synchronization signals via a VHF channel.

The devices according to patents RU 166018 and RU 175803 cannot be used to synchronize secondary clocks with which there is no possibility of establishing communication via a fiber-optic channel, and in the device according to patent RU 175803 the scalability is limited by the number of transmitting and receiving optoelectronic elements contained in it.

It is known (RU 115523) that a device for synchronizing digital stream sources and analog current and voltage setters, aimed at increasing the accuracy of clock synchronization of signal receivers located at a significant distance from each other, is known, comprising at least two input channels from a first interface and a synchronization signal reception unit connected in series, a central control unit, to the inputs of which the outputs of the corresponding synchronization signal reception units and the output of the local synchronization unit are connected, a first synchronization signal distribution unit connected by an input to the output of the central control unit, and second interfaces at the output of the device, wherein synchronization signal transit time compensation units are introduced, connected between the outputs of the first synchronization signal distribution unit and the inputs of the corresponding second interfaces.

The disadvantage of this device is the need to use correction blocks to implement a mechanism for compensating for the delay in signal transmission over communication channels.

Known (RU 2356080) is a system for synchronizing time via a wired radio channel, comprising a master clock, a group of remote clocks, characterized in that the master clock consists of a series-connected software unit for adjusting the clock and a time storage unit, the output of which is connected to the group of remote clocks via a network interface, an additional device for decoding the precise time signal is introduced, consisting of a series-connected radio signal conversion unit, a signal receiver, a software unit for extracting the signal and a communication device, the output of which is connected via a communication interface to the software unit for adjusting the clock, the first input of the radio signal conversion unit is connected to the radio channel by means of galvanic isolation, and the second input is connected to a reference voltage source, the second input of the software unit for extracting the signal is connected to a clock frequency source.

It should be noted that the specified synchronization system uses a complex method of obtaining a reference synchronization signal via radio broadcasts to compensate for delays, and also contains poorly predictable random events in the form of fading, packet loss, etc.

The task that the utility model is aimed at solving is to create a compact, simple, energy-efficient synchronization device that is free from the disadvantages of the above-mentioned analogs due to the fact that it does not have redundant blocks, and the processing and generation of synchronization signals is carried out by hardware.

The technical result of the utility model is an increase in energy efficiency and a simplification of the design while maintaining functional capabilities by eliminating power supplies and interfaces for receiving input synchronization signals, as well as associated logical and software blocks and microcircuits for processing them.

The obtained result is achieved in that a time server is proposed, comprising a unit for receiving, processing and filtering GNSS signals, a real-time clock and reference generator unit, a unit for receiving and generating PTP packets, an SPF interface unit, characterized in that the unit for receiving, processing and filtering GNSS signals, configured to digitally filter phase noise of the 1PPS signal with subsequent formation of a stable frequency based on it, is connected by its output to the first input of a hardware-implemented unit of the real-time clock and reference generator, the second output of which is connected to the first input of the unit for receiving and generating PTP packets, implemented in the form of a set of machines with a fixed response time independent of the load, the second output of which is connected to the second input of the real-time clock unit for implementing synchronization modes from an external grandmaster, and the first output is connected to an SFP interface unit, the first output of which is connected to the second input of the unit for receiving and generating PTP packets for ensuring bidirectional data transmission, wherein the time server is implemented in the form of a module placed in the SFP port of a switch/router.

The essence of the utility model is explained by the figure.

Fig. 1 - structural/electronic/schematic diagram,

Where

1 - block for receiving, processing and filtering GNSS signals,

2 - real time clock and reference generator block,

3 - block for receiving and generating PTP packets,

4 - SFP interface block.

When the cable is connected, the signal from the antenna enters the GNSS signal reception, processing and filtering unit 1, where the signal quality is assessed, phase noise is filtered and stable precise time marks are generated, which are sent to the real-time clock and reference generator unit 2, where the internal real-time clock is synchronized with an external source, and the frequency of the built-in generator is disciplined according to precise time marks (1PPS). The PTP packet reception and generation unit 3 exchanges data with clients and/or other grandmasters, and the time marks added to the PTP packet are received from the real-time clock and reference generator unit 2. The PTP packet is transmitted and received via the SFP interface unit 4, which adapts it at the physical level.

This ensures frequency, time and phase synchronization of telecommunications and industrial equipment using NTP and PTP protocols.

The implementation of the time server as a module placed in the SFP port of the switch/router allows using the switch/router ports to synchronize network devices according to the above protocols without using an external separate server, which in turn allows freeing up space in racks and reducing overall power consumption. In addition, with this implementation, the time server is powered from the SFP port, which makes it possible not to use 220 V AC or 48 V DC power supplies, as well as power filtering circuits, which also allows simplifying the design and making the product more compact and energy efficient.

Claims (1)

A time server comprising a unit for receiving, processing and filtering GNSS signals, a real-time clock and reference generator unit, a unit for receiving and generating PTP packets, an SPF interface unit, wherein the unit for receiving, processing and filtering GNSS signals, configured to digitally filter phase noise of the 1PPS signal with subsequent generation of a stable frequency based on it, is connected by its output to the first input of a hardware-implemented unit of the real-time clock and reference generator, the second output of which is connected to the first input of the unit for receiving and generating PTP packets, implemented in the form of a set of machines with a fixed response time independent of the load, the second output of which is connected to the second input of the real-time clock unit for implementing synchronization modes from an external grandmaster, and the first output is connected to an SFP interface unit, the first output of which is connected to the second input of the unit for receiving and generating PTP packets for ensuring bidirectional data transmission, characterized in that the time server is implemented in the form of a module placed in the SFP port of a switch/router.