CN112202491B - Data transmission method of 5G differential protection device - Google Patents
Data transmission method of 5G differential protection device Download PDFInfo
- Publication number
- CN112202491B CN112202491B CN202011130624.7A CN202011130624A CN112202491B CN 112202491 B CN112202491 B CN 112202491B CN 202011130624 A CN202011130624 A CN 202011130624A CN 112202491 B CN112202491 B CN 112202491B
- Authority
- CN
- China
- Prior art keywords
- data
- module
- time
- differential
- differential protection
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/03—Arrangements for fault recovery
- H04B10/032—Arrangements for fault recovery using working and protection systems
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W8/00—Network data management
- H04W8/30—Network data restoration; Network data reliability; Network data fault tolerance
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Databases & Information Systems (AREA)
- Emergency Protection Circuit Devices (AREA)
- Synchronisation In Digital Transmission Systems (AREA)
Abstract
A data transmission method of a 5G differential protection device belongs to the technical field of relay protection of power systems. The method is completed based on a data processing device, the data processing device comprises a main controller module, a satellite time synchronization module, a FPAG module and a 5G network interface connected with a 5G communication module, and the method comprises the following steps: the sender calculates the acquisition time of the data and sends the data and the calculated acquisition time together; after receiving the data, the receiver calculates the waiting time according to the acquisition time, the expected sending time and the set time delay of the sender, and sends the received data to the differential protection device after the waiting time is reached. When the device and the method provided by the invention are used for upgrading the original optical fiber network into a 5G network, only the hardware device and the front-end processing software of data need to be updated on the original equipment, the core part of a software system does not need to be changed, the workload is greatly reduced, the research and development period is shortened, and the reliability does not need to be verified again.
Description
Technical Field
The invention belongs to the technical field of power system relay protection, and relates to a data transmission method of a 5G differential protection device.
Background
In an electric power system, differential protection requires acquiring synchronous sampling data of equipment on two sides. In the conventional optical fiber differential protection device, the delay of optical signal transmission in the optical fiber is fixed delay, and the optical fiber differential protection device is generally not influenced by the external environment. By measuring the channel delay, the received contralateral data is calculated on the local side time axis, and the synchronization of the sampling data can be realized.
The traditional differential protection device using optical fiber as data transmission medium has been used in large quantity in the field, and the reliability has been verified. However, the special optical fiber pipeline is difficult to lay, the construction cost is high, and some areas do not have optical fiber laying conditions, so that certain restriction is brought to the development of differential protection technology. Secondly, when the optical fiber is broken, the broken position is difficult to search, and the maintenance cost is high.
At present, 5G networks are put into commercial use, the end-to-end delay in 5G network slices reaches within 10 milliseconds, and the characteristic of low delay is favorable for realizing a differential protection function.
In a newly-built substation, a set of 5G differential protection device is respectively configured on two sides of a line, and the scheme is easy to realize by replacing a traditional optical fiber differential protection device.
Although the 5G network has the characteristic of low delay, the delay is unstable, and the optical fiber differential protection device is realized by just utilizing the stability of the optical fiber transmission delay. The 5G network is used for replacing optical fibers, but the system period of software which is newly developed to meet the requirements is long, and the reliability needs to be verified.
Disclosure of Invention
The invention aims to provide equipment and a method, which replace optical fiber communication with 5G communication on the basis of using an original software system and meet the requirement of stable time delay of communication.
In order to achieve the purpose, the invention adopts the following technical scheme: a data transmission method of a 5G differential protection device is completed based on a data processing device, the data processing device comprises a main controller module and a satellite time synchronization module, the main controller module comprises a satellite time synchronization function module connected with the satellite time synchronization module, and the key is that: the data processing device also comprises an FPAG module and a 5G network interface connected with the 5G communication module, and the main controller module also comprises a data processing module connected with the FPGA module and an Ethernet control function module connected with the 5G network interface.
Furthermore, the data processing module comprises a differential data processing functional module and a 5G data conversion and transmission functional module; the FPGA module comprises a data buffer module, a differential receiving and data encryption module and a 5G data receiving and data decryption module.
Further, a stable time delay parameter T3 is set; the data transmission method comprises the following steps:
and (3) data transmission: the 5G data conversion and transmission function module is used for encrypting the data after the differential data receiving and encrypting module receives the differential data of the main controller, calculating to obtain the absolute time generated by generating the differential data and transmitting the absolute time to the main controller; and the 5G data conversion and transmission functional module transmits the differential data and the absolute time for generating the differential data to the 5G network interface through the Ethernet control module.
And (3) receiving data: the 5G data conversion and transmission function module receives data received by the 5G network interface, calculates data buffering time according to T3 after de-framing, calculates time consumed by the FPGA data buffering module for sending data, and sends the data to the 5G data receiving and data decryption module of the FPGA after calculation; the 5G data receiving and data decrypting module completes data decrypting processing and transmits the data decrypting processing to the data buffering module; the data buffer module calculates the waiting time, and sends data to the differential protection data processing function module of the main controller after the waiting time is reached.
When receiving the data, calculating the time of generating differential data, and sending the time and the data of generating differential data to the opposite side through a 5G communication network; after the data frame of the 5G module is received on the opposite side, the waiting time is set according to the time generated by the differential data and the fixed time delay, so that the fixed time delay is realized when the data is transmitted between the two differential protection devices.
Has the advantages that: by adopting the technical scheme provided by the invention, when the 5G network is upgraded on the basis of the original optical fiber network, only the hardware device and the front-end processing software of the data need to be updated on the original equipment, the core part of the software system does not need to be changed, the workload is greatly reduced, the research and development period is shortened, and the reliability does not need to be verified again.
Drawings
FIG. 1 is a schematic diagram of the data processing apparatus,
fig. 2 is a time slot diagram of both sides of the transceiver.
Detailed Description
The invention is further described below with reference to the accompanying drawings.
Referring to fig. 1, the data processing device includes a main controller module and a satellite time synchronization module, the main controller module includes a satellite time synchronization function module connected to the satellite time synchronization module, and the satellite time synchronization module is a GPS module or a beidou time synchronization module.
The FPGA has better time sequence and logic characteristics, so that the FPGA can be used for encrypting and decrypting data, ensuring the data security, buffering received data and achieving the purpose of stabilizing time delay.
The data processing device also comprises an FPAG module and a 5G network interface connected with the 5G communication module, and the main controller module also comprises a data processing module connected with the FPGA module and an Ethernet control function module connected with the 5G network interface.
The data processing module in the main controller module comprises a differential data processing functional module and a 5G data conversion and transmission functional module; the FPGA module comprises a data buffer module, a differential receiving and data encryption module and a 5G data receiving and data decryption module.
The 5G network interface comprises a MAC + PHY module and a SWITCH module, wherein the SWITCH module is connected with the RJ45 interface module and the 5G communication module. An RJ45 network port plug-in 5G CPE device can be used; A5G module may be built in as necessary. The main controller forms an Ethernet channel through MAC + PHY; the Ethernet channels are interconnected by using a SWITCH chip.
The liquid crystal display can carry out device parameter setting, and basic parameters comprise: the 5G terminal is selected and used, and comprises an external 5G CPE and an internal 5G module; setting and reading 5G terminal parameters, including a terminal MAC, a gateway and an APN; setting and reading the IP of the device and the IP of the opposite side device; the stable time delay parameter is set and read, and can be set to any value of 10ms-15 ms.
The main controller module is used as a central control of data flow to realize framing and unframing of data frames. And receiving GPS/Beidou time tick signals, thereby ensuring higher system time precision. And after receiving the FPGA data, the main controller module adds the time mark information of the current point and forms a UDP frame. The UDP frame is transmitted to the opposite-side data processing apparatus through the 5G network. Decoding the UDP frame by the side data processing device, and judging the frame sequence number and the timestamp; sending the application layer data to the FPGA for decryption processing; the FPGA carries out buffering processing on the data according to the set time delay value; and after the set time delay is reached, sending the data to a differential protection data processing functional module of the main controller.
And receiving and transmitting data.
The data processing devices on the side and the opposite side realize the communication function; a stable time delay parameter T3 is set in the data processing device, and T3 is the fixed time delay of data transmitted from the local side differential protection device to the opposite side differential protection device.
The 5G data conversion and transmission function module mainly comprises two parts of functions, namely receiving encrypted differential protection data, forming information such as absolute system time when the differential protection data are generated into a UDP frame form, transmitting the information to a 5G network interface through the Ethernet control module, and sending the information out through a 5G network; secondly, the following steps: receiving contralateral data received by the 5G network interface, calculating data buffering time according to the stable time delay parameter after de-framing, and calculating the count of a timer consumed by the FPGA data buffering module for sending data; and the 5G data receiving and data decrypting module is used for sending the data to the FPGA after the calculation is finished.
The data receiving and encrypting module in the FPGA module has the functions of: 1. and the 5G data conversion and transmission functional module receives the differential data of the main controller, encrypts the data, receives the timer count value consumed by decryption of the differential protection data and sends the timer count value to the main controller. 2. Receiving 5G data after the host controller deframed, data buffering time and timer count consumed by the data buffering module to send data; and finishing data decryption processing.
And the data buffer module in the FPGA module is used for calculating the data retention time, and the timer counts the data retention time and then sends the data to the differential protection data processing functional module of the main controller, so that the stable 5G time delay is realized.
The method comprises the steps of sending data and receiving the data.
And (3) data transmission: after receiving the differential data of the main controller, the differential data receiving and encrypting module encrypts the data, calculates the processing time and sends the processing time to the 5G data conversion and transmission function module of the main controller; the 5G data conversion and transmission function module transmits the differential data and the absolute time for generating the differential data to a 5G network interface through the Ethernet control module, and specifically comprises the following steps:
step S1, when the differential data starts to be received, a timer is started to count, and the timer frequency is Fr ≧ 10 MHz.
And the differential data receiving and encrypting module in the FPGA module receives the differential data of the main controller. When the transmitted data is detected, a timer is started, and the following processing is performed on the data.
And step S2, acquiring the data frame of the differential protection device and putting the data frame into a data buffer area.
And step S3, encrypting the acquired data frame, stopping counting after the encryption processing is finished, and acquiring the count Nr of the timer.
The above completes the processing of the data, and the processing time is determined by the counter. And processing data by the FPGA from the step S1 to the step S3, wherein the FPGA is not connected with the GPS/Beidou time tick signals. Wherein the step S1 starts the timer counting and the step S2 starts simultaneously, not in a sequential order.
And step S4, recording the current system time T1 of the acquired encrypted data, and calculating a received data timestamp Tr = T1-Nr/Fr.
This step is accomplished by the master controller module. Because the FPGA is not connected with the GPS/Beidou time synchronization signal, the system time cannot be acquired, and the time for receiving the differential protection data is calculated by timing of a counter.
Step S5 is to perform packing processing on the time stamp information Tr and the encrypted data.
Step S6, acquiring the MAC address of the device at the side, the MAC address of the 5G terminal, the IP address of the device at the side and the IP address of the device at the opposite side, and transmitting the packaged data to a 5G network interface for sending in a UDP frame form;
the 5G data conversion and transmission function module receives data received by the 5G network interface, calculates data buffering time according to T3 after de-framing, calculates time consumed by the FPGA data buffering module for sending data, and sends the data to the 5G data receiving and data decryption module of the FPGA after calculation; the 5G data receiving and data decrypting module completes data decrypting processing and transmits the data decrypting processing to the data buffering module; the data buffer module calculates the waiting time, and sends data to the differential protection data processing function module of the main controller after the waiting time is reached. The method specifically comprises the following steps:
and step R1, acquiring the opposite side UDP frame received by the 5G network interface.
Step R2, analyzing the data, reading the time stamp Tr of the received UDP frame, reading the current system time T2 and the stable time delay parameter T3, and calculating the data buffering time: Δ T = T3- (T2-Tr), Δ T is in μ s.
And simultaneously executing the step R3, calculating the count of the timer required by data transmission: ns = m × n, where m is the number of bytes of data in the UDP frame, and n is the timer count required for the FPGA to send one byte.
And step R4, starting a timer for counting, wherein the frequency of the timer is Fs, and Fs is ≧ 10 MHz.
Step R5, data decryption; and putting the decrypted data and the data buffering time delta T into a data buffer area.
When the count value Nc = Δ T × Fs-Ns, step R6 transmits the data to the differential protection data processing function module in the main controller module.
Referring to fig. 2, what the method is to achieve is that the time from the start of S1 to the completion of R6 is stabilized to T3.
And the timer count of the transmitting end determines the time consumed by the FPGA to execute the steps S2 and S3, and the main controller obtains the time Tr of the data arrival by acquiring the system time T1 after the step S3 is executed. The execution time of steps S4 to S6 may vary according to the size of the data frame, and the specific time does not affect the execution time. The time delay transmitted through 5G is unstable, i.e., the time between the completion of step S6 and the start of step R1 is unstable.
The steps R2 and R3 are executed simultaneously, R3 predicts the time required for sending data, and after R2 obtains the completion of R2 and R3, the residual time delta T of the fixed time delay T3 is reached from the step S1.
At this time, step R4 starts a timer to start counting; step 5 starts data decryption.
The above realizes the constancy of the transmission-reception interval.
Note that T3 is set to be greater than 5G end-to-end transmission delay + processing transmission time of data in the device. The end-to-end delay in the 5G network slice is within 10 milliseconds, and in the embodiment, T3 is set to 10-15ms, which can meet the requirement.
The timer frequencies Fr and Fs are crystal oscillator main frequencies configured for the FPGA.
Claims (5)
1. A data transmission method of a 5G differential protection device is completed based on a data processing device, the data processing device comprises a main controller module and a satellite time setting module, the main controller module comprises a satellite time setting function module connected with the satellite time setting module,
the data processing device is characterized by further comprising an FPAG module and a 5G network interface connected with the 5G communication module, wherein the main controller module further comprises a data processing module connected with the FPGA module and an Ethernet control function module connected with the 5G network interface;
the data processing module comprises a differential data processing functional module and a 5G data conversion and transmission functional module; the FPGA module comprises a data buffer module, a differential receiving and data encryption module and a 5G data receiving and data decryption module;
setting a stable time delay parameter T3, wherein T3 is the fixed time delay of data sent from the local side differential protection device to the opposite side differential protection device;
the data transmission method comprises the following steps:
and (3) data transmission:
the 5G data conversion and transmission function module is used for encrypting the data after the differential data receiving and encrypting module receives the differential data of the main controller, calculating to obtain the absolute time generated by generating the differential data and transmitting the absolute time to the main controller; the 5G data conversion and transmission functional module transmits the differential data and the absolute time for generating the differential data to a 5G network interface through the Ethernet control module;
and (3) receiving data:
the 5G data conversion and transmission function module receives data received by the 5G network interface, calculates data buffering time according to T3 after de-framing, calculates time consumed by the FPGA data buffering module for sending data, and sends the data to the 5G data receiving and data decryption module of the FPGA after calculation; the 5G data receiving and data decrypting module completes data decrypting processing and transmits the data decrypting processing to the data buffering module; the data buffer module calculates waiting time, and sends data to a differential protection data processing function module of the main controller after the waiting time is reached;
the method specifically comprises the following steps:
the transmission of data includes:
step S1, when the differential data starts to be received, a timer is started to count, and the frequency of the timer is Fr;
step S2, acquiring a data frame of the differential protection device;
step S3, the obtained data frame is encrypted, counting is stopped after the encryption processing is finished, and the count Nr of the timer is obtained;
step S4, recording the current system time T1, and calculating a received data timestamp Tr = T1-Nr/Fr;
step S5, packaging the time stamp information Tr and the encrypted data;
step S6, acquiring the MAC address of the device at the side, the MAC address of the 5G terminal, the IP address of the device at the side and the IP address of the device at the opposite side, and transmitting the packaged data to a 5G network interface for sending in a UDP frame form;
the reception of data comprises
Step R1, acquiring the opposite side UDP frame received by the 5G network interface;
step R2, analyzing the data, reading the time stamp Tr of the received UDP frame, reading the current system time T2 and the stable time delay parameter T3, and calculating the data buffering time:
Δ T = T3- (T2-Tr), Δ T is in units of μ s;
and simultaneously executing the step R3, calculating the count of the timer required by data transmission:
ns = m × n, where m is the number of bytes of data in the UDP frame, and n is the timer count required for the FPGA to send one byte;
step R4, starting a timer for counting, wherein the frequency of the timer is Fs;
step R5, data decryption;
when the count value Nc = Δ T × Fs-Ns, step R6 transmits the data to the differential protection data processing function module in the main controller module.
2. The data transmission method of the 5G differential protection device according to claim 1, wherein the 5G network interface comprises a MAC + PHY module and a SWITCH module, and the SWITCH module is connected with the RJ45 interface module and the 5G communication module.
3. The data transmission method of a 5G differential protection device according to claim 1, characterized in that: the current system time is read from the connected satellite time tick module.
4. The data transmission method of a 5G differential protection device according to claim 1, characterized in that: t3 is 10-15 ms.
5. The data transmission method of a 5G differential protection device according to claim 1, characterized in that: and Fr and Fs are crystal oscillator main frequencies configured by the FPGA.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011130624.7A CN112202491B (en) | 2020-10-21 | 2020-10-21 | Data transmission method of 5G differential protection device |
| PCT/CN2021/084637 WO2022083070A1 (en) | 2020-10-21 | 2021-03-31 | Data transmission method of 5g differential protection apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011130624.7A CN112202491B (en) | 2020-10-21 | 2020-10-21 | Data transmission method of 5G differential protection device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112202491A CN112202491A (en) | 2021-01-08 |
| CN112202491B true CN112202491B (en) | 2021-07-23 |
Family
ID=74008696
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011130624.7A Active CN112202491B (en) | 2020-10-21 | 2020-10-21 | Data transmission method of 5G differential protection device |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN112202491B (en) |
| WO (1) | WO2022083070A1 (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112202491B (en) * | 2020-10-21 | 2021-07-23 | 石家庄科林电气股份有限公司 | Data transmission method of 5G differential protection device |
| CN113472482B (en) * | 2021-06-20 | 2023-11-10 | 许继集团有限公司 | Sampling value data frame protection method and system applied to 5G network data communication |
| CN113612666A (en) * | 2021-08-27 | 2021-11-05 | 国网信息通信产业集团有限公司 | Method and device for measuring time delay of power distribution network differential protection network |
| CN113889983B (en) * | 2021-09-16 | 2024-02-02 | 科大智能电气技术有限公司 | Data transmission and protection system, method and storage device suitable for 5G differential protection |
| CN115190576B (en) * | 2022-02-22 | 2023-10-31 | 南京国电南自电网自动化有限公司 | Wireless differential synchronization system and method for self-adaptive cache depth |
| CN115314467B (en) * | 2022-06-28 | 2023-10-27 | 国网信息通信产业集团有限公司 | Data communication system and method based on distribution network differential protection |
| CN117714031B (en) * | 2024-01-11 | 2024-06-04 | 无锡路通视信网络股份有限公司 | High-speed data encryption communication method |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110838713A (en) * | 2019-11-26 | 2020-02-25 | 山东大学 | 5G network-based distributed differential protection method and system for power distribution network |
| CN111565073A (en) * | 2020-04-14 | 2020-08-21 | 南京国电南自电网自动化有限公司 | Wireless optical difference synchronization method and system based on 5G communication |
| CN111725776A (en) * | 2020-04-27 | 2020-09-29 | 国网江苏省电力有限公司电力科学研究院 | FPGA-based power distribution network current differential protection device |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102546071B (en) * | 2011-12-23 | 2014-08-13 | 北京北方烽火科技有限公司 | Clock synchronization method and system |
| EP3136528B1 (en) * | 2015-08-31 | 2020-04-22 | Siemens Aktiengesellschaft | Differential protection method, differential protection device and differential protection system |
| CN107800590B (en) * | 2017-10-31 | 2020-09-01 | 南方电网科学研究院有限责任公司 | Transmission equipment delay monitoring method and device and switch transmission delay monitoring system |
| CN207410019U (en) * | 2017-11-03 | 2018-05-25 | 山东联合电力技术有限公司 | A kind of power distribution network distribution differential protective system |
| US11630424B2 (en) * | 2018-07-13 | 2023-04-18 | Schweitzer Engineering Laboratories, Inc. | Time signal manipulation detection using remotely managed time |
| CN111668800B (en) * | 2020-04-27 | 2023-01-24 | 南京国电南自电网自动化有限公司 | Line differential protection synchronization method and system based on wireless communication and absolute time |
| CN112202491B (en) * | 2020-10-21 | 2021-07-23 | 石家庄科林电气股份有限公司 | Data transmission method of 5G differential protection device |
-
2020
- 2020-10-21 CN CN202011130624.7A patent/CN112202491B/en active Active
-
2021
- 2021-03-31 WO PCT/CN2021/084637 patent/WO2022083070A1/en active Application Filing
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110838713A (en) * | 2019-11-26 | 2020-02-25 | 山东大学 | 5G network-based distributed differential protection method and system for power distribution network |
| CN111565073A (en) * | 2020-04-14 | 2020-08-21 | 南京国电南自电网自动化有限公司 | Wireless optical difference synchronization method and system based on 5G communication |
| CN111725776A (en) * | 2020-04-27 | 2020-09-29 | 国网江苏省电力有限公司电力科学研究院 | FPGA-based power distribution network current differential protection device |
Non-Patent Citations (2)
| Title |
|---|
| 基于5G技术的配网差动保护应用;张星; 徐文斌; 赵东森;《宁夏电力》;20200628;说明书第[0027]段-[0037]段，附图1-2 * |
| 张星;徐文斌;赵东森.基于5G技术的配网差动保护应用.《宁夏电力》.2020, * |
Also Published As
| Publication number | Publication date |
|---|---|
| WO2022083070A1 (en) | 2022-04-28 |
| CN112202491A (en) | 2021-01-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112202491B (en) | Data transmission method of 5G differential protection device | |
| CN104836630B (en) | IEEE1588 clock synchronization system and implementation method therefor | |
| US8023976B2 (en) | Method and system for accurate clock synchronization for communication networks | |
| US9667408B2 (en) | Communication systems and methods for distributed power system measurement | |
| CA2791698C (en) | Method and system for accurate clock synchronization through interaction between communication layers and sub-layers for communication systems | |
| RU2438247C2 (en) | Method for synchronisation of assemblies in base station | |
| KR101290643B1 (en) | Method and system for bearing time synchronization protocol in optical transport network | |
| US9830298B2 (en) | Media time based USB frame counter synchronization for Wi-Fi serial bus | |
| CN103563287B (en) | Synchronization device and synchronization method | |
| CN112260221B (en) | 5G-optical fiber differential protection data conversion device and method with stable time delay | |
| CN101977104A (en) | IEEE1588 based accurate clock synchronization protocol system and synchronization method thereof | |
| WO2013070797A1 (en) | Physical layer processing of timestamps and mac security | |
| US9042411B1 (en) | System and method for accurate time sampling in presence of output delay | |
| CN104602141A (en) | Method, device and system for synchronizing time in OTN (Open Transport Network) | |
| CN207650573U (en) | A kind of precise synchronization system based on multi-source time service | |
| US11750310B2 (en) | Clock synchronization packet exchanging method and apparatus | |
| CN102263629A (en) | Method for time synchronization among boards, clock board and NE (network element) device | |
| JP6227888B2 (en) | Communication system, synchronization system, and communication method | |
| CN109687927A (en) | A kind of method, communication equipment and the communication system of determining timestamp | |
| CN108738127B (en) | Radio remote unit, baseband processing unit, distributed base station and synchronization method thereof | |
| CN103546273A (en) | Frequency synchronism device and method based on PTP frames | |
| CN107959537B (en) | State synchronization method and device | |
| CN115243362B (en) | Time synchronization system and method applied to traveling wave positioning device | |
| WO2016000324A1 (en) | Method and apparatus for implementing time synchronization | |
| CN113573403B (en) | Slave clock synchronization system and method for 5G RRU |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |