Time synchronization method and device based on base station, communication equipment and medium

Abstract

The invention relates to the field of time synchronization, and discloses a time synchronization method and device based on a base station, communication equipment and a medium, and the time synchronization method based on the base station comprises the steps: obtaining initial clock reference information, transmitting the information to an adjacent base station through an IEEE1588 protocol, and forming a candidate synchronization signal. And based on the candidate synchronization signals, selecting an optimal master clock from the adjacent base stations by adopting an optimal master clock algorithm, and taking the time of the selected master clock as standard time. And based on the selected standard time, the standard time is issued to the whole base station network through cascade transmission among the multiple stages of base stations, so that each base station can perform periodic correction based on the standard time, thereby ensuring unification and accurate synchronization of clocks of the whole network. According to the time synchronization method based on the base stations, the clock synchronization precision between the base stations is effectively improved, clock drift and errors are reduced, and stable operation of the base stations in a complex environment is ensured.

Description

Technical Field

[0001] The present application relates to the technical field of time synchronization, and particularly to a time synchronization method, device, communication equipment and medium based on a base station. Background Art

[0002] In modern communication systems, clock synchronization is the basis for ensuring network stability and efficient operation. Especially in some application scenarios, the requirements for clock synchronization are particularly strict. For example, in specific environments such as hospitals, mines, and factories, clock synchronization not only directly affects the communication quality between devices, but also affects the security and reliability of the network. However, in these environments, traditional clock synchronization schemes face a series of technical challenges.

[0003] Currently, clock synchronization technology mainly relies on external signal sources, especially the GPS system. These systems synchronize the clocks of base stations and network devices by providing accurate timestamps. In an ideal environment, GPS can provide highly accurate time synchronization signals and is widely used in communication networks and data synchronization systems worldwide.

[0004] However, in some special scenarios, such as hospitals, mines, and factories, environmental factors (such as building blockage and deep underground environments) can cause GPS signals to be unable to penetrate effectively or even unable to receive synchronization signals. This makes the traditional GPS-based synchronization scheme unable to be implemented, and the base station cannot obtain precise time synchronization, affecting the overall operation and quality of the communication network.

[0005] The existing synchronization technologies face the following problems:

[0006] Poor signal coverage: In some environments, especially underground or high-density building areas, GPS signals are difficult to transmit, resulting in the base station being unable to obtain external synchronization signals. Even if some signals can be received, the stability and accuracy of the signals will be affected.

[0007] Difficult base station deployment: Due to problems such as poor signal coverage or building interference, it is very difficult to deploy new base stations and synchronize them in these special environments. Traditional schemes rely on external devices, increasing the complexity and cost of base station construction.

[0008] High additional cost: Many existing synchronization schemes require additional hardware devices or complex signal processing, which will greatly increase the cost. Especially in some cost-sensitive industries, this increased overhead may be unaffordable.

[0009] Signal interference problem: When multiple base stations work in parallel, signal interference is a problem that cannot be ignored. Especially in the case of ineffective synchronization, the clock deviation between multiple base stations may cause interference and a decline in communication quality.

[0010] Therefore, how to achieve accurate base station clock synchronization in special environments with poor signal coverage and inability to obtain external synchronization signals has become an important issue that needs to be solved urgently at present. Summary of the Invention

[0011] In view of this, embodiments of the present application provide a time synchronization method, device, communication equipment and medium based on a base station, which can effectively solve the problems of difficult base station synchronization, clock drift and high hardware cost in the prior art in environments with poor signal coverage and inability to obtain external synchronization signals.

[0012] In a first aspect, embodiments of the present application provide a time synchronization method based on a base station, including:

[0013] Obtain initial clock reference information;

[0014] Use the IEEE1588 protocol to send the initial clock reference information to adjacent base stations to form candidate synchronization signals;

[0015] Based on the candidate synchronization signals, use the best master clock algorithm to obtain a master clock among the adjacent base stations, and use the time of the master clock as the standard time;

[0016] Based on the standard time, through cascaded transmission between multiple levels of base stations, send the standard time to the entire base station network, so that each level of base station performs periodic correction based on the standard time.

[0017] In some embodiments, the base station is deployed with a GPS module, and the obtaining of the initial clock reference information includes:

[0018] When the base station is in an open environment, receive GPS time signals in real time through the GPS module;

[0019] Demodulate the GPS time signal, extract time information and perform preliminary error correction to generate the initial clock reference information.

[0020] In some embodiments, the obtaining of the initial clock reference information further includes:

[0021] When the base station is in a non-open environment, perform air interface synchronization with a macro base station and enable the NTP service to obtain TOD time information from the network, and preprocess the TOD time information to form preliminary time data;

[0022] After filtering, averaging and error correction of the preliminary time data, output calibrated high-precision time information as the initial clock reference information.

[0023] In some embodiments, sending the initial clock reference information to an adjacent base station by using the IEEE 1588 protocol to form a candidate synchronization signal includes:

[0024] Encapsulating the initial clock reference information into a PTP synchronization message in the format specified by the IEEE 1588 protocol;

[0025] Sending the PTP synchronization message to the adjacent base station through the network interface of the base station;

[0026] At the adjacent base station, parsing the PTP synchronization message, extracting the initial clock reference information, and using the initial clock reference information as a candidate synchronization signal.

[0027] In some embodiments, based on the candidate synchronization signal, obtaining a master clock among the adjacent base stations by using the best master clock algorithm and using the time of the master clock as the standard time includes:

[0028] Extracting the time synchronization parameters of each base station from the candidate synchronization signal;

[0029] Comparing the priorities of the time synchronization parameters according to the best master clock algorithm, and selecting the candidate synchronization signal with the highest priority as the master clock signal;

[0030] Using the time information in the master clock signal as the standard time.

[0031] In some embodiments, based on the standard time, sending the standard time to the entire base station network through cascaded transmission between multiple levels of base stations, so that each level of base station performs periodic correction based on the standard time, includes:

[0032] Encapsulating the standard time into a synchronization message and sending it to the next-level base station adjacent to the current base station through the network interface of the base station;

[0033] The next-level base station receives and parses the synchronization message, extracts the standard time, uses the standard time as a reference to perform periodic correction on the local clock, and encapsulates the corrected standard time into the synchronization message and sends it to the next-level base station again through the network interface until all base stations in the entire base station network complete periodic correction based on the received standard time.

[0034] In some embodiments, the periodic correction of the local clock further includes:

[0035] In each base station, based on the 1PPS signal in the received standard time, using an FPGA or a PLL to lock the 1PPS signal;

[0036] Using the locked 1PPS signal to correct the local clock.

[0037] In a second aspect, an embodiment of the present application provides a time synchronization device based on a base station, including:

[0038] A clock reference information acquisition module, configured to acquire initial clock reference information;

[0039] A candidate synchronization signal formation module, configured to use the IEEE1588 protocol to transmit the initial clock reference information to an adjacent base station to form a candidate synchronization signal;

[0040] A standard time acquisition module, configured to, based on the candidate synchronization signal, use the best master clock algorithm to acquire a master clock among the adjacent base stations and use the time of the master clock as the standard time;

[0041] A time correction module, configured to, based on the standard time, through cascaded transmission between multiple levels of base stations, send the standard time to the entire base station network, so that each level of base station performs periodic correction based on the standard time.

[0042] In a third aspect, an embodiment of the present application provides a communication device, the communication device includes a processor and a memory, the memory stores a computer program, and the processor is configured to execute the computer program to implement the above-mentioned time synchronization method based on a base station in the first aspect.

[0043] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, when the computer program is executed on a processor, implementing the above-mentioned time synchronization method based on a base station in the first aspect.

[0044] The embodiments of the present application have the following beneficial effects:

[0045] A time synchronization method based on a base station in the present application, by acquiring initial clock reference information, combining with the IEEE1588 protocol to send this information to an adjacent base station to form a candidate synchronization signal. On this basis, the best clock algorithm is used to dynamically select the optimal master clock among the adjacent base stations and use its time as the standard time to ensure the unity and accuracy of the clocks of the base stations throughout the network. Subsequently, through cascaded transmission between multiple levels of base stations, the standard time is continuously transmitted to the entire base station network, and each level of base station can perform periodic correction based on this standard time to eliminate clock drift caused by network delay or other factors. A time synchronization method based on a base station in the present application not only optimizes the clock synchronization process of the base station, but also effectively improves the synchronization accuracy, avoids communication interruption or performance degradation problems caused by clock deviation, and meets the high requirements for clock synchronization accuracy and network stability in complex scenarios. Description of the Drawings

[0046] To more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required for use in the embodiments. It should be understood that the following drawings only show some embodiments of the present application and should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other relevant drawings can also be obtained based on these drawings.

[0047] Figure 1 Fig. shows a flowchart of a time synchronization method based on a base station according to an embodiment of the present application;

[0048] Figure 2 Fig. shows a schematic diagram of a base station performing time synchronization in a time synchronization method based on a base station according to an embodiment of the present application;

[0049] Figure 3 Fig. shows a schematic diagram of correcting time in a time synchronization method based on a base station according to an embodiment of the present application;

[0050] Figure 4 Fig. shows a schematic structural diagram of a time synchronization device based on a base station according to an embodiment of the present application. Detailed Embodiments

[0051] The following will clearly and completely describe the technical solutions in the embodiments of the present application in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, rather than all embodiments.

[0052] The components of the embodiments of the present application generally described and illustrated in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the present application claimed, but merely represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts fall within the scope of protection of the present application.

[0053] Hereinafter, the terms "including", "having" and their cognates that can be used in various embodiments of the present application are only intended to represent specific features, numbers, steps, operations, elements, components or combinations of the foregoing items, and should not be construed as first excluding the existence of one or more other features, numbers, steps, operations, elements, components or combinations of the foregoing items or increasing the possibility of one or more features, numbers, steps, operations, elements, components or combinations of the foregoing items. In addition, the terms "first", "second", "third", etc. are only used for differential description and cannot be understood as indicating or implying relative importance.

[0054] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which various embodiments of the present application belong. The terms (such as those defined in a general use dictionary) will be interpreted as having the same meaning as the contextual meaning in the relevant technical field and will not be interpreted as having an idealized meaning or an overly formal meaning unless clearly defined in various embodiments of the present application.

[0055] The following will, with reference to the accompanying drawings, elaborate on some embodiments of the present application. Without conflict, the following embodiments and the features in the embodiments may be combined with each other.

[0056] Considering the problems of difficult base station synchronization, clock drift, and high hardware costs in an environment with poor signal coverage and inability to obtain external synchronization signals in the prior art, a time synchronization method based on a base station is proposed. By using the base station device itself as a synchronization relay and adopting multi-level base station cascade transmission and an internal clock correction mechanism, high-precision clock synchronization without additional hardware support is achieved.

[0057] Figure 1 A flowchart of a time synchronization method based on a base station according to an embodiment of the present application is shown. Exemplarily, the method includes the following steps:

[0058] Step S100, obtain initial clock reference information.

[0059] The initial clock reference information is to provide an accurate time reference for the base station to ensure the synchronization of the entire base station network. Specifically, the base station can obtain the initial clock reference information in two different ways: one is to directly obtain the GPS time signal through GPS, and the other is to perform air interface synchronization through a macro base station and start the NTP (Network Time Protocol) service to obtain time information from the network. Whether it is GPS reception or NTP acquisition, the obtained time information will undergo error correction and filtering processing, and finally generate high-precision initial clock reference information, which is used as the input for the subsequent synchronization process.

[0060] In an alternative embodiment, step S100 includes: when the base station is in an open environment, the GPS module receives the GPS time signal in real time. Demodulate the GPS time signal, extract time information, and perform preliminary error correction to generate initial clock reference information.

[0061] Exemplarily, the base station is deployed with a GPS module, and receives time signals from GPS satellites through the GPS module deployed by itself. The GPS time signal has a globally unified time standard (UTC time), so it is very suitable for precise time synchronization. The GPS module of the base station continuously receives and decodes the GPS signal, extracts the time information therein, and uses it as the initial time reference information of the base station.

[0062] Once the GPS time signal is received, the base station demodulates it and converts the received analog signal into a digital signal. Subsequently, specific time data is extracted from the signal, including information such as year, month, day, hour, minute, and second. Since the signal transmission process may be affected by environmental factors, for example, multipath effects or signal attenuation, it is necessary to perform preliminary error correction on the received GPS time signal. Through algorithms, such as the average value method, the signal errors caused by environmental factors are corrected to ensure that the generated initial clock reference information has high accuracy.

[0063] In an alternative embodiment, step S100 further includes: when the base station is in a non-open environment, perform air interface synchronization with the macro station and enable the NTP service, obtain TOD time information from the network, and preprocess the TOD time information to form preliminary time data. After filtering, averaging, and error correction on the preliminary time data, calibrated high-precision time information is output as the initial clock reference information.

[0064] Exemplarily, air interface synchronization is to transmit time information between the base station and the macro station through a wireless communication link. In an environment where GPS signals cannot be received, the base station obtains the time information provided by the macro station through air interface synchronization. At the same time, the base station can also provide the NTP service to obtain TOD time information (Time of Day) from the network. By synchronizing with the macro station or the network, the base station can obtain a preliminary time reference.

[0065] The obtained TOD time information may be affected by network latency and other factors, so it needs to be preprocessed. The preprocessing process includes error compensation, time deviation correction, etc. The base station processes the received time information according to a preset algorithm to eliminate errors caused by transmission delays or data losses.

[0066] The preliminary processed time data is further filtered and averaged to remove possible noise interference. Through this processing, a stable time reference can be obtained. In addition, the error correction process can further eliminate errors caused by network latency or hardware instability. After these processes, the accuracy of the output time information is significantly improved and becomes the initial clock reference information of the local base station and the entire base station network.

[0067] Step S200: Send the initial clock reference information to adjacent base stations using the IEEE 1588 protocol to form candidate synchronization signals.

[0068] The base station obtains high-precision initial clock reference information through GPS or NTP and transmits it to adjacent base stations through the network. Through the IEEE 1588 protocol, the base station can ensure high-precision transmission of time information and minimize network latency, thus laying the foundation for the whole network clock synchronization. Finally, adjacent base stations generate candidate synchronization signals based on the received initial clock reference information, providing support for subsequent master clock selection and cascaded transmission of standard time.

[0069] In an optional embodiment, step S200 includes: encapsulating the initial clock reference information into a PTP synchronization message according to the format specified by the IEEE 1588 protocol. Send the PTP synchronization message to adjacent base stations through the network interface of the base station. At the adjacent base station, parse the PTP synchronization message, extract the initial clock reference information, and use the initial clock reference information as a candidate synchronization signal.

[0070] Exemplarily, the base station encapsulates the timestamp and synchronization control fields in the specified positions of the message according to the standard PTP message structure to ensure the integrity and accuracy of the data. The generated PTP synchronization message not only contains the time information of the local base station, but also includes synchronization accuracy, clock correction information, etc., ensuring that downstream base stations can accurately interpret it.

[0071] After completing the encapsulation of the PTP synchronization message, the base station sends the synchronization message to adjacent base stations through the network interface (such as Ethernet interface, optical fiber interface, etc.). In this step, the base station will transmit the encapsulated PTP synchronization message through the network layer protocol (such as UDP or TCP). Since the IEEE 1588 protocol supports low-latency and high-precision synchronous transmission, the data packet will minimize the time delay during transmission to ensure the real-time and accuracy of the message.

[0072] When the adjacent base station receives the PTP synchronization message, it parses the message according to the provisions of the IEEE 1588 protocol. The adjacent base station first checks the synchronization message header to ensure that the message format meets the protocol requirements and is not damaged. The parsing process includes extracting key data such as timestamp information and clock deviation values from the message. After parsing, the base station will extract the initial clock reference information and store it in the local time synchronization module. At this time, the initial clock reference information becomes a candidate synchronization signal for subsequent steps. Finally, the base station uses the parsed initial clock reference information as a candidate synchronization signal, preparing for master clock selection and further time synchronization.

[0073] Step S300: Based on the candidate synchronization signals, obtain the master clock in adjacent base stations using the Best Master Clock (BMC) algorithm, and use the time of the master clock as the standard time.

[0074] Selecting the master clock from adjacent base stations based on the candidate synchronization signals through the BMC (Best Master Clock) algorithm is the core step to achieve network-wide time synchronization. The role of this step is to automatically select the most accurate clock signal through the algorithm and use the time of this clock signal as the standard time for network-wide synchronization. The candidate synchronization signals are usually provided by multiple adjacent base stations, including information from multiple time sources. The BMC algorithm selects the optimal clock signal as the standard time based on factors such as the priority, stability, and accuracy of each signal, thus ensuring that the clock synchronization in the entire network remains consistent and avoiding the time drift problem between different base stations.

[0075] In an optional embodiment, step S300 includes: extracting the time synchronization parameters of each base station from the candidate synchronization signals. Comparing the priorities of the time synchronization parameters according to the Best Master Clock algorithm, and selecting the candidate synchronization signal with the highest priority as the master clock signal. Using the time information in the master clock signal as the standard time.

[0076] Exemplarily, each adjacent base station provides a candidate synchronization signal, and these synchronization signals contain time synchronization parameters such as timestamps, clock accuracies, and clock offsets. The base station first extracts these time synchronization parameters from the received synchronization signals. The extracted parameters include the current time of the clock (e.g., hours, minutes, seconds), the timestamp (indicating the moment when the signal is received), and the clock offset (indicating the deviation of the clock from the standard time). These parameters are used to describe the quality and stability of the candidate synchronization signals.

[0077] After extracting the time synchronization parameters of the candidate synchronization signals, the BMC algorithm starts to compare the priorities of these parameters. The BMC algorithm determines which base station's clock is the most accurate by comparing factors such as the clock accuracy, clock stability, and signal delay of different base stations. The BMC algorithm will evaluate the stability of each base station's signal and assign corresponding priorities based on information such as its accuracy, reliability, and delay.

[0078] The BMC algorithm will finally select the candidate synchronization signal with the highest priority as the master clock signal. This process ensures that the most accurate and stable time signal is selected as the standard time source to be provided to other base stations for synchronization. The time information in the selected master clock signal will be extracted and used as the standard time for subsequent base station synchronization.

[0079] Step S400: Based on the standard time, the standard time is sent to the entire base station network through cascade transmission between multiple base stations, so that base stations at all levels can perform periodic corrections based on the standard time.

[0080] First, after obtaining the initial clock reference information, the base station sends the standard time to the adjacent base station through a transmission protocol (such as the IEEE1588 protocol). The base station that receives the standard time uses it as a reference and adjusts the local clock through periodic corrections to ensure that the local clock is consistent with the standard time. Then, the corrected standard time is passed to the next level base station through the network interface to continue time synchronization. In this process, each level of base station relies on the corrected standard time of the previous level base station, and passes it on step by step until all base stations in the entire base station network are synchronized. In this way, the clock synchronization of the entire network is guaranteed, thereby achieving large-scale, high-precision wireless signal synchronization.

[0081] In an optional embodiment, step S400 includes: encapsulating the standard time into a synchronization message, and sending it to a next-level base station adjacent to the current base station through a network interface of the base station. The next-level base station receives and parses the synchronization message, extracts the standard time, uses the standard time as a reference, periodically corrects the local clock, and encapsulates the corrected standard time into a synchronization message, and sends it to the next-level base station through the network interface again, until all base stations in the entire base station network complete the periodic correction based on the received standard time.

[0082] Exemplarily, the base station encapsulates the standard time into a synchronization message. The format of the synchronization message is specified according to the IEEE1588 protocol, which includes parameters such as accurate time information, clock deviation, and clock stability. With this information, the receiver can accurately correct the local clock. The synchronization message is transmitted to the adjacent next-level base station through the network interface of the base station (such as Ethernet or optical fiber interface).

[0083] The next-level base station that receives the synchronization message first decodes and parses the message. During the parsing process, the base station extracts the standard time information from the synchronization message. The base station will further adjust the standard time based on the clock synchronization parameters in the protocol (such as clock deviation). By processing the received standard time, the base station can ensure that its clock is consistent with the master clock.

[0084] The next-level base station uses the extracted standard time as the reference time and uses the internal time synchronization algorithm (such as PLL or other phase-locked loop technology) to periodically correct the base station's local clock. This process ensures that the base station's clock will not be affected by factors such as network delays and equipment aging, thereby maintaining a high synchronization accuracy.

[0085] The corrected local clock signal is repackaged into a synchronization message and sent to the next-level base station through the same network interface. This message contains the latest time information of the local clock, ensuring that the receiving party can continue clock synchronization. This process is repeated throughout the base station network, with each level of base station acting as a "relay" station to transmit and correct the standard time step by step until all base stations in the network are synchronized.

[0086] By continuously repeating the above process, the standard time information is gradually transmitted to each base station in the network. All base stations perform periodic corrections based on the received standard time, thus ensuring the accuracy and stability of the clock synchronization of the entire base station network. This multi-level cascaded transmission and correction method not only improves the synchronization accuracy but also ensures that the base stations can maintain consistent clocks in an environment with poor signal coverage.

[0087] In an optional embodiment, step S400 further includes: in each base station, based on the 1PPS signal in the received standard time, using an FPGA or a PLL to lock the 1PPS signal. Using the locked 1PPS signal to correct the local clock.

[0088] In this embodiment, first, the base station receives the standard time information from the previous-level base station or an external synchronization source. The standard time information includes a 1PPS signal, which is a timing pulse signal with the characteristic of triggering once per second. The base station uses the received 1PPS signal as a reference signal for local clock synchronization.

[0089] The received 1PPS signal is locked through FPGA or PLL (phase-locked loop) technology. The role of the FPGA or PLL is to ensure the accuracy of the 1PPS signal and eliminate the deviation caused by network delay, transmission error, or hardware operation delay. Specifically, the FPGA or PLL compares the received 1PPS signal with the local clock and adjusts the local clock frequency to make it consistent with the 1PPS signal. Through this locking process, the accuracy and stability of the local clock are greatly improved.

[0090] After the 1PPS signal is successfully locked, the base station will use this signal to correct the local clock. Every time a 1PPS signal is received, the base station will adjust its system time. To eliminate the errors caused by network delay or software and hardware operation delays, the base station will perform the following process:

[0091] 1PPS interrupt function: When the 1PPS signal triggers an interrupt, the base station immediately reads the current system time.

[0092] Time data processing: The system time consists of two data, the second level (s level) and the nanosecond level (ns level). Every 5 seconds, the base station clears the nanosecond-level data and increments the second-level data by one to form new time data. Since the 1PPS signal interruption moment should be at the whole second, the base station corrects the time error introduced by network delay and software and hardware operation delays through this operation to ensure clock accuracy.

[0093] After the new system time is generated, the base station sets it as the current system time. At this time, the clock of the base station has been optimized and can be more accurately synchronized with the external standard time. To ensure the effectiveness of the correction setting of the local clock, the base station will perform three corrections within 10 seconds. Through three consecutive corrections, the base station can maximize the elimination of possible errors and ensure the stability and reliability of clock synchronization.

[0094] The local clock corrected by the 1PPS signal is encapsulated as a synchronization message and transmitted to the next-level base station through the network interface of the base station. After receiving the corrected synchronization message, the next-level base station continues to correct the local clock, thus completing the clock synchronization process of the entire base station network.

[0095] Illustrated with a specific example:

[0096] As Figure 2 shown, base station A0 (located in an open environment) receives GPS signals in real time through the GPS module and uses this signal as the standard time source. At this time, the clock accuracy of base station A0 is very high because the GPS signal provides the global standard time (UTC). As a master clock source, base station A0 sends synchronization messages to its adjacent base stations (B0, B1, C2, C3) through the protocol of the PTP module (IEEE1588).

[0097] Meanwhile, base station A1 is located in a non-open environment with weak signals and cannot directly receive GPS signals. Therefore, base station A1 synchronizes with the macro station through the air interface and enables the NTP service to obtain TOD (Time of Day) time information from the network. Although base station A1 relies on the network to obtain time, this does not affect its ability to participate in synchronization as a relay device. Base station A1 propagates the synchronization information to the lower-level base stations through the NTP service.

[0098] Both base stations A0 and A1 serve as the primary clock sources and send the standard time information to the next-level base stations B0, B1, C2, and C3 through the PTP protocol. After receiving the PTP packets, these base stations compare the priorities of the candidate clock signals through the BMC algorithm. During this process, base stations B0, B1, C2, and C3 will first check the priority1 parameter (priority). If the priorities of two base stations are the same, they will further compare parameters such as clock-class, and finally select the most accurate clock source as the primary clock. For example, if the GPS signal provided by base station A0 has higher accuracy, the BMC algorithm will select base station A0 as the primary clock and use its time information as the standard time for network synchronization. At this time, the time of base station A0 will become the reference time of the system, and all base stations will correct based on the time of A0.

[0099] Once base station A0 or A1 is selected as the primary clock, the 1PPS signal (pulse per second signal) will be transmitted along with the standard time. Since there may be deviations in the transmission process of the 1PPS signal, the base station needs to lock it through FPGA or PLL (phase-locked loop) technology. For example, after receiving the 1PPS signal sent by A0, base station B0 locks it through FPGA or PLL technology to ensure that the local clock can be accurately aligned with the 1PPS signal and eliminate the deviations caused by network delay and hardware delay. The locked 1PPS signal is used to adjust the local clock of base station B0 to keep it consistent with the standard time.

[0100] Since the TOD time information (i.e., the standard time) may have a certain delay during transmission, each base station will use the locked 1PPS signal to correct the TOD time information of the local clock of the base station. The specific process is as Figure 3 shown.

[0101] Whenever the 1PPS signal triggers an interruption, the base station (e.g., base station B0) will enter the PPS interruption function. At the entrance of the function, the system will count and increment the value of variable n, representing the current number of times the 1PPS signal is triggered. Every 5 seconds, the base station will check the value of counter n and determine whether it is a multiple of 5 (n % 5 == 1). If so, the base station will read the current system time and divide it into two parts: the second level (s level) and the nanosecond level (ns level). Then, the base station will clear the nanosecond-level data and increment the second-level data by one. The purpose of this operation is to ensure that the time point of the 1PPS signal aligns with the whole second, eliminating time errors caused by network latency, software and hardware latency, etc. After correcting the clock, the base station will set the new system time as the current time to ensure that the local clock aligns with the external synchronization signal. In this way, through the locked 1PPS signal, the base station can accurately synchronize the clock. To ensure the effectiveness of the clock correction settings, the base station will perform three corrections within 10 seconds. This multiple correction ensures the stability and consistency of the system time, avoiding clock drift caused by error accumulation. After the slave base stations such as base stations B0 and B1 complete the clock correction, the 1PPS signal and TOD time information will continue to be transmitted to the next-level base stations (e.g., base stations C2 and C3) through the PTP protocol. Through this cascaded transmission between multiple-level base stations, the standard time information can be disseminated level by level to ensure the clock synchronization of all base stations in the network.

[0102] By using the 1PPS signal for clock correction, the base station can effectively eliminate the errors caused by transmission delays and achieve the clock synchronization of all base stations in the network through multi-level cascaded transmission. After each base station performs periodic correction using the 1PPS signal, it can ensure the efficient operation of the communication system and avoid network instability or communication interruption problems caused by clock deviations. Through this clock synchronization between multiple-level base stations, the system can ensure that the accessed terminals are not affected by clock drift or synchronization problems during the movement process, ensuring stable and uninterrupted communication. For example, in environments such as hospitals or factories, the movement of terminal devices will not cause communication disconnection or signal loss because each base station is accurately synchronized based on the standard time, avoiding signal interference caused by clock asynchronization.

[0103] Figure 4 FIG. shows a schematic structural diagram of a base-station-based time synchronization device 40 according to an embodiment of the present application. Exemplarily, the device includes:

[0104] A clock reference information acquisition module 41 for acquiring initial clock reference information;

[0105] A candidate synchronization signal formation module 42 for transmitting the initial clock reference information to an adjacent base station using the IEEE1588 protocol to form a candidate synchronization signal;

[0106] A standard time acquisition module 43, configured to obtain a master clock in the adjacent base stations based on the candidate synchronization signal by using the best master clock algorithm, and use the time of the master clock as the standard time;

[0107] A time correction module 44, configured to transmit the standard time to the entire base station network through cascaded transmission between multiple levels of base stations based on the standard time, so that each level of base station performs periodic correction based on the standard time.

[0108] It can be understood that the device in this embodiment corresponds to the method in the above embodiment, and the optional items in the above embodiment are also applicable to this embodiment, so they will not be repeated here.

[0109] This application also provides a communication device. Exemplarily, the communication device may be a device such as a base station. The communication device includes a processor and a memory. The memory stores a computer program, and the processor runs the computer program to enable the communication device to execute the functions of the above method or each module in the above device.

[0110] Among them, the processor may be an integrated circuit chip with signal processing capabilities. The processor may be a general-purpose processor, including at least one of a central processing unit (CPU), a graphics processing unit (GPU), a network processor (NP), a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, and discrete hardware components. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc., which can implement or execute the various methods, steps, and logic block diagrams disclosed in the embodiments of the present application.

[0111] The memory may be, but is not limited to, a random access memory (RAM), a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), etc. The memory is used to store the computer program, and after receiving the execution instruction, the processor can execute the computer program accordingly.

[0112] The present application also provides a computer-readable storage medium for storing the computer program used in the above communication device. For example, the computer-readable storage medium may include, but is not limited to, various media that can store program codes such as USB flash drives, mobile hard disks, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical discs.

[0113] In several embodiments provided by the present application, it should be understood that the disclosed apparatus and method can also be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the flowcharts and structure diagrams in the accompanying drawings show the possible architectures, functions, and operations of the apparatus, method, and computer program product according to multiple embodiments of the present application. In this regard, each block in the flowchart or block diagram may represent a module, a program segment, or a part of code, and the module, program segment, or part of code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in alternative implementations, the functions marked in the blocks may occur in a different order than marked in the accompanying drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the structure diagram and / or flowchart, as well as the combination of blocks in the structure diagram and / or flowchart, can be implemented by a dedicated hardware-based system that performs the specified functions or actions, or can be implemented by a combination of dedicated hardware and computer instructions.

[0114] In addition, each functional module or unit in various embodiments of the present application may be integrated together to form an independent part, or each module may exist separately, or two or more modules may be integrated to form an independent part.

[0115] If the above functions are implemented in the form of software functional modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for causing a communication device (which may be a smart phone, a personal computer, a server, or a network communication device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present application.

[0116] As described above, it is only the specific implementation manner of this application, but the protection scope of this application is not limited thereto. Any person skilled in the art within the technical scope disclosed by this application can easily think of changes or substitutions, which should all be covered within the protection scope of this application.

Claims

1. A time synchronization method based on a base station, characterized in that, The method includes: Obtaining initial clock reference information; Using the IEEE1588 protocol to send the initial clock reference information to an adjacent base station to form a candidate synchronization signal; Based on the candidate synchronization signal, using the best master clock algorithm to obtain a master clock among the adjacent base stations, and using the time of the master clock as the standard time; Based on the standard time, through cascaded transmission between multiple-level base stations, sending the standard time to the entire base station network, so that each level of base station performs periodic correction based on the standard time.

2. The time synchronization method based on a base station according to claim 1, wherein The base station is equipped with a GPS module, and the obtaining of the initial clock reference information includes: When the base station is in an open environment, receiving the GPS time signal in real time through the GPS module; Demodulating, extracting time information and performing preliminary error correction on the GPS time signal to generate the initial clock reference information.

3. The method for time synchronization based on a base station according to claim 1, wherein The obtaining of the initial clock reference information further includes: When the base station is in a non-open environment, performing air interface synchronization with a macro base station and enabling the NTP service, obtaining TOD time information from the network, and preprocessing the TOD time information to form preliminary time data; After filtering, averaging and error correction on the preliminary time data, outputting calibrated high-precision time information as the initial clock reference information.

4. The time synchronization method based on a base station according to claim 1, wherein The using the IEEE1588 protocol to send the initial clock reference information to an adjacent base station to form a candidate synchronization signal includes: Encapsulating the initial clock reference information into a PTP synchronization message in the format specified by the IEEE1588 protocol; Sending the PTP synchronization message to the adjacent base station through the network interface of the base station; At the adjacent base station, parsing the PTP synchronization message, extracting the initial clock reference information, and using the initial clock reference information as the candidate synchronization signal.

5. The time synchronization method based on a base station according to claim 1, characterized in that, The based on the candidate synchronization signal, using the best master clock algorithm to obtain a master clock among the adjacent base stations, and using the time of the master clock as the standard time includes: Extracting the time synchronization parameters of each base station from the candidate synchronization signal; Comparing the priorities of the time synchronization parameters according to the best master clock algorithm, and selecting the candidate synchronization signal with the highest priority as the master clock signal; Using the time information in the master clock signal as the standard time.

6. The method for time synchronization based on a base station according to claim 1, wherein The based on the standard time, through cascaded transmission between multiple-level base stations, sending the standard time to the entire base station network, so that each level of base station performs periodic correction based on the standard time includes: Encapsulating the standard time into a synchronization message and sending it to the next-level base station adjacent to the current base station through the network interface of the base station; The next-level base station receives and parses the synchronization message, extracts the standard time, uses the standard time as a reference to perform periodic correction on the local clock, and encapsulates the corrected standard time into the synchronization message, and sends it to the next-level base station again through the network interface until all base stations in the entire base station network have completed periodic correction based on the received standard time.

7. The method for time synchronization based on a base station according to claim 6, wherein The periodic correction of the local clock further includes: In each base station, based on the received 1PPS signal in the standard time, the 1PPS signal is locked by using an FPGA or a PLL; The local clock is corrected by using the locked 1PPS signal.

8. A time synchronization device based on a base station, characterized in that, The device includes: A clock reference information acquisition module, configured to acquire initial clock reference information; A candidate synchronization signal formation module, configured to transmit the initial clock reference information to an adjacent base station by using the IEEE1588 protocol to form a candidate synchronization signal; A standard time acquisition module, configured to acquire a master clock in the adjacent base stations by using the best master clock algorithm based on the candidate synchronization signal, and use the time of the master clock as the standard time; A time correction module, configured to transmit the standard time to the entire base station network through cascaded transmission between multiple levels of base stations based on the standard time, so that each level of base station performs periodic correction based on the standard time.

9. A communication device, characterized in that, The communication device includes a processor and a memory, the memory stores a computer program, and the processor is configured to execute the computer program to implement the base station-based time synchronization method according to any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, It stores a computer program, and when the computer program is executed on a processor, it implements the base station-based time synchronization method according to any one of claims 1-7.

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