Uplink synchronization method and device, electronic equipment, storage medium and program product

Abstract

The invention provides an uplink synchronization method and device, electronic equipment, a storage medium and a program product, and relates to the technical field of communication. The uplink time delay deviation of the gateway station is adapted by directly adjusting the uplink frame timing of the satellite base station, and the defect that TA instructions are frequently sent to the gateway station in a traditional method is overcome. Therefore, the downlink signaling overhead is obviously reduced, the resource utilization rate of the downlink is improved, and the synchronization deviation risk caused by the calculation error and the time delay change of the gateway station is also reduced. Besides, through adjustment of the base station side, dependence on adjustment of the gateway station side is reduced, and the problem of synchronization failure caused by untimely or inaccurate adjustment of the gateway station is avoided at the same time.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to an uplink synchronization method, device, electronic device, storage medium, and program product. Background Art

[0002] In 5G non-terrestrial network communication scenarios, satellite base stations are responsible for processing uplink signals from gateways. To achieve uplink synchronization, accurately aligning signals from different gateways, each experiencing different propagation delays, at the base station relies primarily on delay compensation at the gateway. Specifically, the gateway uses ephemeris data to calculate the unilateral delay between itself and the satellite. It then advances this delay when sending the uplink signal. This compensates for the signal's propagation time in space, ensuring that the signal arrives at the base station in sync with signals from other gateways.

[0003] However, due to potential errors in ephemeris data, the gateway's estimated latency may also be inaccurate. Therefore, the satellite base station sends a timing advance (TA) to the gateway during and after the gateway access process. In 5G satellite communications, it's common for multiple gateways to access the satellite base station simultaneously. To maintain uplink synchronization between these gateways, the base station needs to frequently send TAs to each gateway. This frequent signaling consumes significant downlink bandwidth resources, impacting downlink throughput. Summary of the Invention

[0004] The purpose of the embodiments of the present application is to provide an uplink synchronization method, device, electronic device, storage medium and program product to improve the problem in the prior art that satellite base stations frequently send TAs to signal gateways, which consumes a large amount of downlink bandwidth resources and affects the downlink throughput rate.

[0005] In a first aspect, an embodiment of the present application provides an uplink synchronization method, which is applied to a satellite base station, wherein one feed beam of the satellite base station is connected to only one gateway station, and the method includes: measuring an uplink timing deviation of an uplink signal sent by the gateway through the feed beam, wherein the uplink timing deviation is a deviation between an arrival time of the uplink signal and an expected time; The uplink frame timing of the satellite base station is adjusted according to the uplink timing deviation.

[0006] In this implementation, the uplink delay deviation of the gateway is adapted by directly adjusting the satellite base station's uplink frame timing, avoiding the drawbacks of traditional methods that frequently send TA commands to the gateway. This not only significantly reduces downlink signaling overhead and improves downlink resource utilization, but also mitigates the risk of synchronization deviation caused by gateway calculation errors and delay variations. Furthermore, base station-side adjustments reduce reliance on gateway-side adjustments and avoid synchronization failures caused by untimely or inaccurate gateway adjustments.

[0007] Optionally, adjusting the uplink frame timing of the satellite base station according to the uplink timing deviation includes: If the uplink timing deviation is delayed by a first duration, adjusting the uplink frame timing of the satellite base station to delay by the first duration; If the uplink timing deviation is advanced by the second time period, the uplink frame timing of the satellite base station is adjusted to advance by the second time period.

[0008] In this implementation, the satellite base station's uplink frame timing is precisely adjusted to accommodate variations in the gateway's uplink signal delay. The positive or negative value of the uplink timing deviation determines the delay or advance of the base station's uplink frame timing. This flexible adjustment mechanism effectively mitigates the impact of factors such as gateway delay estimation errors, delay variations caused by satellite motion, and gateway crystal oscillator drift on uplink synchronization.

[0009] Optionally, after measuring the uplink timing deviation of the uplink signal sent by the gateway through the feed beam, the method further includes: When the uplink timing deviation exceeds a set threshold, a TA instruction is sent to the gateway, where the TA instruction includes the uplink timing deviation.

[0010] In this implementation, precise adjustment of the gateway's uplink transmission time is achieved by sending a TA command to the gateway when the uplink timing deviation exceeds a set threshold. This method not only effectively corrects large delay deviations, ensuring accurate alignment of the uplink signal with the base station's uplink frame, but also avoids the downlink signaling overhead caused by frequent TA command transmission when the deviation is small.

[0011] Optionally, adjusting the uplink frame timing of the satellite base station according to the uplink timing deviation includes: The uplink frame timing of the satellite base station is adjusted according to the uplink timing deviation in accordance with an adjustment period, wherein the uplink timing deviation is measured at a time closest to the adjustment period.

[0012] In the above implementation process, by reasonably setting the adjustment period, it is possible to reduce unnecessary adjustment operations and reduce base station overhead while ensuring synchronization accuracy.

[0013] Optionally, the adjustment period is determined according to the elevation angle of the satellite where the satellite base station is located, and the adjustment period is positively correlated with the elevation angle.

[0014] In this implementation, dynamic optimization of satellite base station uplink frame timing adjustment is achieved by setting a positive correlation between the adjustment period and the satellite's elevation angle. This dynamic adjustment of the period based on elevation angle more accurately adapts to varying latency characteristics, ensuring stable uplink synchronization at varying elevation angles.

[0015] Optionally, the adjustment period is determined by: Calculating a bilateral delay variation rate between the satellite and the gateway according to the orbital altitude and elevation angle of the satellite; An adjustment period is calculated according to the maximum allowable delay deviation and the bilateral delay change rate.

[0016] In this implementation, the bilateral delay change rate is calculated by comprehensively considering the satellite's orbital altitude and elevation angle. This is then combined with the maximum allowable delay deviation to determine the adjustment period, enabling refined management of uplink synchronization adjustments in satellite communication systems. This dynamic rate-of-change adjustment period calculation method accurately addresses real-time variations in delay between the satellite and the gateway, ensuring that uplink signals maintain stable synchronization with the base station under varying orbital altitudes and elevation angles.

[0017] Optionally, the maximum allowable delay deviation is determined by: Obtaining the CP length configured by the satellite base station; The maximum allowable delay deviation is determined according to the CP length.

[0018] In the above implementation, the CP length is a key parameter for preventing intersymbol interference (ISI) in OFDM systems. Its length directly determines the maximum tolerable delay spread. By associating the maximum allowable delay deviation with the CP length, this solution ensures that the delay deviation of the uplink signal can be effectively controlled without exceeding the CP guard interval, thereby avoiding ISI caused by excessive delay and ensuring communication quality.

[0019] Optionally, the adjustment period is determined by: The current adjustment period is determined according to a pre-configured mapping relationship between the elevation angle and the adjustment period.

[0020] In the above implementation process, the current adjustment period is determined by the pre-configured mapping relationship between the elevation angle and the adjustment period, thereby achieving efficient management of uplink synchronization adjustment in the satellite communication system.

[0021] In a second aspect, an embodiment of the present application provides an uplink synchronization device, which is applied to a satellite base station, wherein one feed beam of the satellite base station is connected to only one gateway station, and the device includes: a deviation measurement module, configured to measure an uplink timing deviation of an uplink signal sent by the gateway via the feed beam, wherein the uplink timing deviation is a deviation between an arrival time of the uplink signal and an expected time; A timing adjustment module is used to adjust the uplink frame timing of the satellite base station according to the uplink timing deviation.

[0022] In a third aspect, an embodiment of the present application provides an electronic device comprising a processor and a memory, wherein the memory stores computer-readable instructions. When the computer-readable instructions are executed by the processor, the steps in the method provided in the first aspect above are executed.

[0023] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the steps in the method provided in the first aspect are executed.

[0024] In a fifth aspect, an embodiment of the present application provides a computer program product, comprising computer program instructions, which, when read and executed by a processor, execute the steps in the method provided in the first aspect above.

[0025] Other features and advantages of the present application will be described in the following description and, in part, will become apparent from the description or be understood by practicing the embodiments of the present application. The objectives and other advantages of the present application can be achieved and obtained through the structures particularly pointed out in the written description, claims, and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0027] Figure 1 A system architecture diagram of an application of this solution provided in an embodiment of the present application; Figure 2 A flowchart of an uplink synchronization method provided in an embodiment of the present application; Figure 3 A schematic diagram of uplink signal delay and uplink frame timing delay provided in an embodiment of the present application; Figure 4A schematic diagram of uplink signal advance and uplink frame timing advance provided in an embodiment of the present application; Figure 5 A structural block diagram of an uplink synchronization device provided in an embodiment of the present application; Figure 6 A structural diagram of an electronic device for executing an uplink synchronization method provided in an embodiment of the present application. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present application.

[0029] It should be noted that the terms "system" and "network" in the embodiments of the present invention are used interchangeably. "Multiple" refers to two or more. In view of this, in the embodiments of the present invention, "multiple" can also be understood as "at least two." "And / or" describes the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / ", unless otherwise specified, generally indicates that the related objects are in an "or" relationship.

[0030] It should also be noted that all actions of obtaining signals, information or data in this application are carried out in compliance with the relevant data protection laws and policies of the country where they are located and with the authorization given by the owner of the corresponding device.

[0031] The technical solution of the present application can be applied to non-terrestrial network (NTN) systems such as satellite communication systems, high altitude platform station (HAPS) communications, for example, integrated communication and navigation (ICaN) systems, global navigation satellite systems (GNSS), etc.

[0032] Satellite communication systems can be integrated with traditional mobile communication systems. For example, the mobile communication system can be a fifth generation (5G) communication system (e.g., a new radio (NR) system), as well as future mobile communication systems.

[0033] Satellite communication systems can be divided into three types based on the satellite's orbital altitude: geostationary Earth orbit (GEO) satellite communication systems, also known as synchronous orbit satellite communication systems; medium Earth orbit (MEO) satellite communication systems; and low Earth orbit (LEO) satellite communication systems. GEO satellites have an orbital altitude of 35,786 km. Their main advantages are their ability to remain stationary relative to the Earth and provide a large coverage area. However, GEO satellite communication also has significant disadvantages: GEO satellite orbits are far from the Earth, resulting in high free-space propagation losses, which limits communication link budgets. Furthermore, to increase transmit or receive gain, satellites must be equipped with larger antennas. GEO communication transmission latency is high, reaching a round-trip delay of approximately 500ms, making it inadequate for low-latency services. GEO orbital resources are also relatively limited, resulting in high launch costs and an inability to provide coverage in the Earth's polar regions. MEO satellites orbit at altitudes between 2,000 and 35,786 km. Their advantage is that they can achieve global coverage with a relatively small number of satellites. However, their orbits are higher than LEO, and communication transmission latency is still higher than that of LEO satellites. LEO satellites, on the other hand, orbit at altitudes between 300 and 2,000 km. LEO satellites are lower than MEO and GEO orbits, offering advantages such as lower data transmission latency, lower transmission loss, and lower launch costs. Of course, in some specific application scenarios, LEO satellites can be replaced with GEO or MEO satellites, or even a combination of multiple types of satellites.

[0034] The satellite system used in the embodiments of the present application may be a non-geostationary orbit satellite system, namely, MEO or LEO.

[0035] The satellite communication systems mainly used in this application are as follows Figure 1 As shown in Figure 1, the satellite internet network is divided into the space segment, ground segment, and user segment. The space segment primarily refers to satellites in orbit. The ground segment includes surface facilities such as operations centers, gateways, and tracking and control stations, which primarily manage, process, and operate satellite internet services. The user segment primarily refers to user terminals that communicate via satellite, including fixed and mobile terminals.

[0036] The communication link between the satellite and the user end is called the user link, the communication link between the satellite and the gateway is called the feeder link (also called the feeder link in the figure), and the communication link between satellites is called the intersatellite link.

[0037] In satellite internet, satellites operating in regenerative mode function as base stations (hereinafter referred to as satellite base stations). These base stations connect gateways and terminals, detecting signals sent by terminals, processing them, and forwarding them to the gateways. Communication between the satellite base stations and the core network occurs through the gateways.

[0038] The gateway is the key connection point between the ground communication network and the satellite communication network. It is mainly responsible for converting the signals of the ground network into signals suitable for satellite transmission, and converting the signals sent back by the satellite into signals that can be recognized by the ground network, thereby realizing the interconnection between the ground network and the satellite network.

[0039] The satellite base station mentioned in the embodiments of the present application may also be a satellite, or a network-side device mounted on a satellite.

[0040] The uplink synchronization method of this application is applied to scenarios where a satellite base station's feed beam is connected to only one gateway. A feed beam is a high-gain, narrow beam used by a satellite to transmit signals to or receive signals from a ground gateway in a satellite communication system. It is used to transmit high-speed data, including user data and control signals, between a satellite and a ground gateway.

[0041] Feed beams are typically used to establish dedicated communication links between satellites and ground gateways, typically connecting to only one gateway. If multiple gateways are connected, the uplink latency of each gateway may vary. The satellite base station cannot uniformly adjust the uplink frame timing to meet the latency requirements of multiple gateways. This can cause the uplink signals of some gateways to lose synchronization with the base station's uplink frames, resulting in inter-symbol interference (ISI) and impacting communication quality.

[0042] Therefore, in this solution, the satellite base station directly adjusts its own uplink frame timing offset to adapt to the gateway's uplink delay deviation to maintain uplink synchronization. When the feed beam is connected to only one gateway, the base station only needs to consider the delay of that single gateway, and can accurately adjust its own uplink frame timing, thereby achieving uplink signal synchronization.

[0043] Example 1 Please refer to Figure 2 , Figure 2 A flowchart of an uplink synchronization method provided in an embodiment of the present application, the method comprising the following steps: Step S110: measuring the uplink timing deviation of the uplink signal sent by the gateway through the feeder beam.

[0044] During or after access, the gateway can send uplink signals to the satellite base station via the feeder beam (i.e., feeder link). These signals may include PRACH (Physical Random Access Channel), PUSCH (Physical Uplink Shared Channel), PUCCH (Physical Uplink Control Channel), SRS (Sounding Reference Signal), etc.

[0045] The satellite base station receives the uplink signal and records its arrival time. Based on its internal clock and predefined frame structure, the satellite base station determines the expected arrival time of the uplink signal. It then calculates the uplink timing deviation, which is the difference between the uplink signal's arrival time and the expected time. This uplink timing deviation reflects the difference between the uplink signal sent by the gateway and the satellite base station's uplink frame timing.

[0046] Step S120: adjusting the uplink frame timing of the satellite base station according to the uplink timing deviation.

[0047] Based on the calculated uplink timing deviation, the direction and magnitude of the satellite base station's uplink frame timing adjustment are determined. For example, if the uplink signal arrives later than expected, the satellite base station's uplink frame timing needs to be delayed. If the uplink signal arrives earlier than expected, the satellite base station's uplink frame timing needs to be adjusted forward.

[0048] Specifically, the baseband processing unit of the satellite base station can be responsible for performing the adjustment of the uplink frame timing. By modifying the generation logic of the internal clock or frame synchronization signal, the uplink frame timing is adjusted to a new position. The adjusted uplink frame timing will serve as the benchmark for subsequent reception and processing of uplink signals.

[0049] After the uplink frame timing is adjusted, various components within the satellite base station (such as the signal receiver, demodulator, and decoder) need to reconfigure their operating parameters based on the adjusted uplink frame timing. For example, the signal receiver needs to adjust the position of its sampling window, and the demodulator needs to perform symbol synchronization based on the new frame timing.

[0050] In some implementations, if the uplink timing deviation is delayed for a first period, the uplink frame timing of the satellite base station is adjusted to be delayed for the first period; if the uplink timing deviation is advanced for a second period, the uplink frame timing of the satellite base station is adjusted to be advanced for the second period.

[0051] like Figure 3 As shown, the uplink signal sent by the gateway is delayed for the first time period T delay, then the uplink frame timing of the satellite base station is also delayed by T delay .like Figure 4 As shown, the uplink signal sent by the gateway is advanced by the second time length T prep , then the uplink frame timing of the satellite base station is also advanced by T prep This flexible adjustment mechanism can effectively reduce the impact of factors such as gateway delay estimation errors, delay variations caused by satellite motion, and gateway crystal oscillator drift on uplink synchronization.

[0052] In this implementation, the uplink delay deviation of the gateway is adapted by directly adjusting the satellite base station's uplink frame timing, avoiding the drawbacks of traditional methods that frequently send TA commands to the gateway. This not only significantly reduces downlink signaling overhead and improves downlink resource utilization, but also mitigates the risk of synchronization deviation caused by gateway calculation errors and delay variations. Furthermore, base station-side adjustments reduce reliance on gateway-side adjustments and avoid synchronization failures caused by untimely or inaccurate gateway adjustments.

[0053] Example 2 Based on the above-mentioned embodiment 1, on the gateway side, although the satellite base station does not send a TA to the gateway, the gateway can calculate the delay based on the ephemeris information and its own latitude and longitude information it obtains, and perform delay compensation on the sent uplink signal before sending it to the satellite base station. However, due to factors such as the ephemeris information, longitude and latitude information, and the crystal oscillator drift of the gateway itself, the delay estimated by the gateway may have errors. Even if the gateway has performed delay compensation on the uplink signal, the sent uplink signal still cannot be synchronized with the satellite base station time. Therefore, the base station side also needs to measure the uplink timing deviation of the uplink signal and adjust the uplink frame timing based on the uplink timing deviation.

[0054] However, when the TA is large, it takes the satellite base station a long time to adjust the uplink timing. During this period, the timing inaccuracy will cause the signal-to-noise ratio to drop, affecting the uplink throughput. Therefore, in this solution, if the uplink timing deviation exceeds a set threshold, a TA command is sent to the gateway. The TA command includes the uplink timing deviation.

[0055] The threshold can be determined based on system performance requirements. For example, the NR system has clear requirements for latency and synchronization, specifying the maximum allowable latency deviation and TA adjustment accuracy. Therefore, the threshold can be set to the maximum allowable latency deviation. Delay deviation exceeding a certain range can cause intersymbol interference (ISI) and increase the bit error rate (BER). The threshold must be set to ensure that delay deviation does not cause significant ISI within the allowable BER range.

[0056] Alternatively, historical measurement data can be analyzed to understand the distribution and changing trends of latency deviation. Threshold settings can be designed based on statistical information such as the maximum, minimum, and average values ​​in the historical measurement data. Alternatively, machine learning algorithms can be used to analyze historical measurement data to predict latency deviation trends, allowing for more appropriate threshold settings.

[0057] The satellite base station compares the measured uplink timing deviation with a set threshold to determine whether to make a timing adjustment. If the uplink timing deviation exceeds the set threshold, the satellite base station generates a TA command containing the uplink timing deviation information. The TA value is equal to the uplink timing deviation. The satellite base station sends the TA command to the gateway via the downlink control channel. The gateway monitors this channel to receive control information from the satellite base station. After receiving the TA command, the gateway analyzes the uplink timing deviation and adjusts the transmission time of its own uplink signal based on the analyzed uplink timing deviation. The gateway updates internal timing parameters, such as the uplink timing advance. If the deviation in the command indicates a delay, the gateway postpones the transmission of the uplink signal by that amount; if it indicates an advance, the signal is transmitted by that amount.

[0058] In this implementation, precise adjustment of the gateway's uplink transmission time is achieved by sending a TA command to the gateway when the uplink timing deviation exceeds a set threshold. This method not only effectively corrects large delay deviations, ensuring accurate alignment of the uplink signal with the base station's uplink frame, but also avoids the downlink signaling overhead caused by frequent TA command transmission when the deviation is small.

[0059] Example 3 Based on the above-mentioned embodiment one and / or embodiment two, in order to avoid the satellite base station from frequently adjusting the uplink frame timing and increasing the power consumption of the satellite base station, the uplink frame timing of the satellite base station can be adjusted according to the uplink timing deviation according to the adjustment period, wherein the uplink timing deviation is measured at the most recent moment from the adjustment period.

[0060] There are two ways to understand this implementation: (1) Measure the uplink timing deviation and adjust the uplink frame timing according to the adjustment period.

[0061] In this mode, the satellite base station measures the uplink timing deviation of the uplink signal according to the adjustment period and adjusts the uplink frame timing accordingly. For example, if the adjustment period is 5ms, the satellite base station measures the uplink timing deviation of the uplink signal every 5ms. If there is no uplink signal during that 5ms period, the uplink frame timing is adjusted using the most recently measured uplink timing deviation. Alternatively, the satellite base station waits for a set time, such as 1ms. If an uplink signal is received during this period, the uplink timing deviation is measured and the uplink frame timing is adjusted. If no uplink signal is received during this period, the uplink frame timing is adjusted using the most recently measured uplink timing deviation.

[0062] (2) Measure the uplink timing deviation in real time and adjust the uplink frame timing according to the adjustment period.

[0063] In this approach, the satellite base station measures the uplink timing deviation each time it receives an uplink signal and stores the deviations in chronological order. When an adjustment period arrives, the satellite base station retrieves the most recently measured uplink timing deviation to adjust the uplink frame timing. Alternatively, the satellite base station may store the most recently measured uplink timing deviation within each adjustment period. For example, each time a new uplink timing deviation is measured, the previous uplink timing deviation is overwritten and stored. When an adjustment period arrives, the satellite base station reads the most recently stored uplink timing deviation and adjusts the uplink frame timing.

[0064] In some implementations, the adjustment period may be set to a fixed period, such as 20 ms, according to system requirements.

[0065] In some implementations, the adjustment period can be set based on adjustment requirements. For example, a satellite base station can obtain historical delay patterns based on historical measurement data and determine the period of delay variation. For example, if the delay deviation changes little over a period of time, this period can be determined as the adjustment period. Alternatively, the adjustment period can be dynamically changed based on historical delay patterns. For example, as the delay continuously changes with the movement of the satellite, the adjustment period can be dynamically determined based on the delay variation. If the delay changes rapidly, the adjustment period can be set relatively short; if the delay changes slowly, the adjustment period can be set longer.

[0066] In the above implementation process, by reasonably setting the adjustment period, it is possible to reduce unnecessary adjustment operations and reduce base station overhead while ensuring synchronization accuracy.

[0067] Based on the above embodiment, the adjustment period may be determined according to the elevation angle of the satellite where the satellite base station is located, and the adjustment period is positively correlated with the elevation angle.

[0068] The elevation angle of a satellite refers to the angle between the satellite and the horizon where the gateway station is located. It is usually used to describe the position of the satellite when it passes above the gateway station at a certain moment. For example, an elevation angle of 90° means that the satellite is directly above the gateway station.

[0069] Based on geometric relationships, as the elevation angle increases, the straight-line distance between the satellite and the gateway decreases, the relative velocity between the satellite and the gateway decreases, and the delay variation rate gradually decreases. In this case, the change in uplink timing deviation may be small, so a longer adjustment period can be set. However, as the elevation angle decreases, the relative velocity between the satellite and the gateway increases in certain directions, causing the delay variation rate to gradually increase. In this case, the change in uplink timing deviation may be large, so a shorter adjustment period can be set. Therefore, the adjustment period is positively correlated with the satellite's elevation angle.

[0070] In practice, the satellite base station determines the satellite's position using the satellite's own navigation system or orbital parameters provided by a ground control center. The gateway station uses positioning technology to obtain its own position and transmits this information to the satellite base station. The satellite base station then uses a geometric algorithm to calculate the satellite's elevation angle based on the satellite's position, the gateway's location, and the Earth's curvature.

[0071] The satellite base station can be preconfigured with a possible range of adjustment periods. A mapping relationship between the elevation angle range and the adjustment period can be established. This mapping relationship can be static, such as adjustment period x - elevation angle range (a1, a2). When establishing this mapping relationship, the smaller the elevation angle, the smaller the adjustment period, while the larger the elevation angle, the longer the adjustment period. This mapping relationship can be pre-established through experiments and stored in the satellite base station.

[0072] Therefore, the adjustment period can be determined based on a preconfigured mapping between the adjustment period and the elevation angle range. For example, if the satellite's elevation angle is calculated to be within the elevation angle range (a1, a2), the current adjustment period x can be determined based on this mapping. In this case, when the satellite moves within this elevation angle range (a1, a2), the uplink frame timing is adjusted according to this adjustment period x. In this case, the satellite base station can update the adjustment period based on the satellite's elevation angle range and adjust the uplink frame timing based on the latest adjustment period.

[0073] For example, within the elevation angle range (a1, a2), the adjustment period is 20ms. The satellite base station adjusts the uplink frame timing every 20ms. If the satellite moves to the elevation angle range (a3, a4), the adjustment period becomes 25ms. The base station then uses the latest 25ms adjustment period. If the previous adjustment period was 20ms, the current adjustment period becomes 25ms. This allows the uplink frame timing to be adjusted dynamically based on the adjustment period.

[0074] That is, during the communication process, if the position of the satellite changes, resulting in a change in the elevation angle, the adjustment period should be recalculated to ensure the accuracy and stability of uplink synchronization.

[0075] The above mapping relationship can also be a dynamic relationship. For example, a linear relationship can be expressed as: adjustment period = a * elevation angle + b, where a and b are positive constants. Then, the specific adjustment period can be calculated by substituting the currently measured elevation angle into this mapping relationship.

[0076] In this implementation, dynamic optimization of satellite base station uplink frame timing adjustment is achieved by setting a positive correlation between the adjustment period and the satellite's elevation angle. This dynamic adjustment of the period based on elevation angle more accurately adapts to varying latency characteristics, ensuring stable uplink synchronization at varying elevation angles.

[0077] Based on the above embodiment, in determining the adjustment period, the bilateral delay change rate between the satellite and the gateway can be calculated based on the satellite's orbital altitude and elevation angle, and then the adjustment period can be calculated based on the maximum operating delay deviation and the bilateral delay change rate.

[0078] The bilateral delay variation rate is negatively correlated with the elevation angle. The bilateral delay variation rate refers to the rate of change of the round-trip signal propagation delay between the satellite and the gateway station over time. As the satellite moves in orbit, the distance between it and the gateway station changes over time, resulting in changes in the signal propagation delay.

[0079] Satellite orbits have specific inclinations, which determine the direction of the satellite's motion relative to the Earth's equatorial plane and affect the cloud component of the satellite relative to the gateway at different locations. For example, the satellite's velocity vector can be decomposed into three components: radial (pointing toward or away from the Earth's center), transverse (perpendicular to the radial direction, along the tangent of the satellite's orbit), and perpendicular to the orbital plane (usually small and negligible). For satellites in near-circular orbits, the radial velocity component is relatively small, with the transverse velocity component being the primary velocity component.

[0080] As the elevation angle increases, the satellite's position in the sky gradually rises. At this point, the satellite's radial velocity component decreases, and the rate of change of the bilateral delay decreases. Specifically, as the satellite rises from a low to a high elevation angle, the projection of its lateral velocity component in the direction of the gateway's line of sight gradually decreases, while the radial velocity component may gradually increase (if the satellite's orbit is circular or near-circular, the radial velocity component may approach zero). This change causes the component of the relative velocity between the satellite and the gateway in the direction of signal propagation to gradually decrease, thereby gradually reducing the rate of change of the bilateral delay.

[0081] When the satellite reaches its maximum elevation angle, it begins to move toward the horizon, and the elevation angle gradually decreases. At this point, the component of the relative velocity between the satellite and the gateway in the direction of signal propagation begins to increase again, causing the bilateral delay variation rate to gradually increase.

[0082] Based on the above principles, the calculation formula for the bilateral delay change rate can be constructed as follows:

[0083] Where c represents the speed of light, Where d represents the elevation angle and d represents the orbital altitude. For an orbital altitude of 600 km and an elevation angle of 10°, the calculated bilateral delay variation rate is approximately 45.4 μs / s. However, this formula is only a simplified example; actual calculations may require consideration of more complex satellite motion models and factors such as the Earth's curvature.

[0084] In a specific implementation, the satellite base station can obtain the satellite's orbital altitude and current elevation angle information through the satellite communication system or from the ground control center. This information is usually known in the satellite communication network or can be calculated through the satellite's position and the geographical location of the gateway.

[0085] Based on the satellite orbit altitude and elevation angle, the bilateral delay change rate between the satellite and the gateway can be calculated using the above calculation formula. Then, the adjustment period can be calculated based on the maximum allowable delay deviation and the bilateral delay change rate.

[0086] The maximum allowable delay deviation can be pre-configured, for example, according to system regulations. The calculation formula for the adjustment period can be as follows: Adjustment period = maximum allowable delay deviation / bilateral delay change rate.

[0087] In this way, the adjustment period can be obtained according to the above formula, and the satellite base station can adjust the uplink frame timing according to the obtained adjustment period.

[0088] It can be understood that the uplink synchronization method of this solution can be applied both during and after a gateway station connects to a satellite base station. Initially, the satellite base station measures the uplink timing deviation of the gateway station's uplink signal and adjusts the uplink frame timing. Simultaneously, the satellite base station also obtains the satellite's elevation angle based on the above method and calculates an adjustment period. If the adjustment period is 20ms, the satellite base station adjusts the uplink frame timing accordingly. Then, at the 20ms mark, the satellite base station adjusts the uplink frame timing. At this point, the satellite base station synchronously obtains the satellite's current elevation angle and calculates an adjustment period. If the adjustment period is 25ms, indicating that the adjustment period needs to be updated, the new adjustment period takes effect, indicating that the uplink frame timing adjustment will be triggered only after 25ms. This method is continued to determine the adjustment period, allowing the adjustment period to dynamically change with changes in elevation angle, thereby dynamically adjusting the uplink frame timing.

[0089] In some other implementations, when calculating the bilateral delay change rate as mentioned above, a differential algorithm can be used for calculation. For example, the bilateral delay change of the signal over a period of time is measured, and the bilateral delay change amount / the period of time is divided to obtain the bilateral delay change rate. Then, the elevation angle of the satellite during this period is recorded. After the adjustment period is calculated based on the maximum allowable delay deviation and the bilateral delay change rate, a correspondence can be established between the elevation angle range of the satellite during this period and the adjustment period. This correspondence can be stored as the mapping relationship in the above embodiment.

[0090] Of course, the adjustment period can be calculated using the above formula. Alternatively, the adjustment period can be pre-calculated based on different elevation angles, and the corresponding relationship between the elevation angle and the adjustment period can be stored. Subsequently, the satellite base station can quickly obtain the corresponding adjustment period based on the elevation angle according to the mapping relationship, eliminating the need for further calculation, thereby saving computing resources of the satellite base station.

[0091] In this implementation, the bilateral delay change rate is calculated by comprehensively considering the satellite's orbital altitude and elevation angle. This is then combined with the maximum allowable delay deviation to determine the adjustment period, enabling refined management of uplink synchronization adjustments in satellite communication systems. This dynamic rate-of-change adjustment period calculation method accurately addresses real-time variations in delay between the satellite and the gateway, ensuring that uplink signals maintain stable synchronization with the base station under varying orbital altitudes and elevation angles.

[0092] Based on the above embodiment, the above maximum allowable delay deviation can also be determined based on the cyclic prefix (CP), that is, the CP length configured by the satellite base station is obtained, and then the maximum allowable delay deviation is determined according to the CP length.

[0093] The primary function of the CP is to prevent inter-symbol interference (ISI), and its length determines the maximum tolerable delay variation. The CP length can be obtained from the satellite base station configuration file, which is set by system designers or network operators based on specific communication requirements and system design. The 5G NR standard defines the range and default value of the CP length. Base stations and gateways are designed to adhere to these standards to ensure inter-system compatibility. For example, the common CP length in the 5G NR standard is 2.08µs (microseconds) to prevent ISI.

[0094] For example, if the CP length is 2.08 μs, to ensure that inter-symbol interference is within an acceptable range, the maximum allowable delay deviation should not exceed half the CP length, that is, 2.08 / 2 = 1.04 μs. Therefore, the maximum allowable delay deviation can be set to be less than or equal to half the CP length.

[0095] When a gateway accesses the network, the base station sends CP configuration information to the gateway. The gateway then sends uplink signals based on the CP length in the CP configuration information. Therefore, the CP length can also be obtained from the uplink signal.

[0096] In the above implementation process, by associating the maximum allowable delay deviation with the CP length, this solution ensures that the delay deviation of the uplink signal can be effectively controlled without exceeding the CP protection interval, thereby avoiding inter-symbol interference caused by excessive delay and ensuring communication quality.

[0097] Example 4 In certain situations, based on the above-mentioned first, second, and / or third embodiments, the gateway may not be able to continuously obtain satellite ephemeris information after access. Consequently, the gateway may be unable to independently estimate the delay and compensate for the uplink signal. Therefore, in this solution, the satellite base station can also send TAs to the gateway at a specific delivery period when synchronously adjusting the uplink frame timing.

[0098] In other words, in addition to sending TA commands to the gateway when the uplink timing deviation exceeds the set threshold, the satellite base station also sends TA commands according to a sending period. Because the satellite base station adjusts the uplink frame timing itself, the sending period can be set to be longer, meaning that TA commands do not need to be sent frequently.

[0099] Regarding the setting of the sending cycle, the period for sending TA by the satellite base station in the traditional solution can be longer, so that the frequency of sending TA by the satellite base station is lower, thereby reducing the sending of TA and improving the downlink throughput.

[0100] In some implementations, the downlink period can be similar to the adjustment period described above. After calculating the adjustment period based on the satellite's elevation angle, the downlink period can be greater than the adjustment period (of course, the specific greater value can be flexibly set based on needs, such as greater than half the adjustment period. For example, if the adjustment period is 20ms, the downlink period is 30ms), or it can be less than twice the adjustment period. After the adjustment period expires, the satellite base station first adjusts the uplink frame timing and then issues the TA command when the downlink period arrives. In this way, when the next adjustment period arrives, the gateway has already adjusted the signal transmission time based on the issued TA. After the satellite base station receives the uplink signal, the change in the uplink timing deviation is unlikely to be significant, allowing for rapid adjustment of the uplink frame timing.

[0101] Please refer to Figure 5 , Figure 5 This is a block diagram of the structure of an uplink synchronization device 200 provided in an embodiment of the present application. The uplink synchronization device 200 may be a module, program segment, or code on an electronic device (such as a satellite base station). It should be understood that the uplink synchronization device 200 corresponds to the above-mentioned method embodiment and is capable of performing each step involved in the method embodiment. The specific functions of the uplink synchronization device 200 can be found in the description above, and a detailed description is omitted here to avoid repetition.

[0102] Optionally, the uplink synchronization device 200 includes: a deviation measurement module 210, configured to measure an uplink timing deviation of an uplink signal sent by the gateway via the feed beam, the uplink timing deviation being a deviation between an arrival time of the uplink signal and an expected time; The timing adjustment module 220 is configured to adjust the uplink frame timing of the satellite base station according to the uplink timing deviation.

[0103] Optionally, the timing adjustment module 220 is used to adjust the uplink frame timing of the satellite base station to delay the first duration if the uplink timing deviation is delayed for the first duration; if the uplink timing deviation is advanced for the second duration, adjust the uplink frame timing of the satellite base station to advance the second duration.

[0104] Optionally, the uplink synchronization device 200 further includes: The TA sending module is configured to send a TA instruction to the gateway when the uplink timing deviation exceeds a set threshold, wherein the TA instruction includes the uplink timing deviation.

[0105] Optionally, the timing adjustment module 220 is configured to adjust the uplink frame timing of the satellite base station according to the uplink timing deviation in accordance with an adjustment period, wherein the uplink timing deviation is measured at a moment closest to the adjustment period.

[0106] Optionally, the adjustment period is determined according to the elevation angle of the satellite where the satellite base station is located, and the adjustment period is positively correlated with the elevation angle.

[0107] Optionally, the timing adjustment module 220 is configured to calculate a rate of change of the bilateral delay between the satellite and the gateway according to the orbital altitude and elevation angle of the satellite; and calculate an adjustment period according to the maximum allowable delay deviation and the rate of change of the bilateral delay.

[0108] Optionally, the timing adjustment module 220 is configured to obtain a CP length configured by the satellite base station; and determine the maximum allowable delay deviation according to the CP length.

[0109] Optionally, the timing adjustment module 220 is configured to determine a current adjustment period according to a pre-configured mapping relationship between the elevation angle and the adjustment period.

[0110] It should be noted that those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working process of the device described above can refer to the corresponding process in the aforementioned method embodiment and will not be repeated here.

[0111] Please refer to Figure 6 , Figure 6 A structural diagram of an electronic device for executing an uplink synchronization method provided in an embodiment of the present application, wherein the electronic device may include: at least one processor 310, such as a CPU, at least one communication interface 320, at least one memory 330 and at least one communication bus 340. The communication bus 340 is used to realize connection and communication between these components. The communication interface 320 of the device in the embodiment of the present application is used to communicate signaling or data with other node devices. The memory 330 can be a high-speed RAM memory or a non-volatile memory, such as at least one disk storage. The memory 330 can optionally be at least one storage device located away from the aforementioned processor. Computer-readable instructions are stored in the memory 330. When the computer-readable instructions are executed by the processor 310, the electronic device executes the above-mentioned method process.

[0112] I understand. Figure 6 The structure shown is only for illustration, and the electronic device may also include Figure 6 More or fewer components than shown, or with Figure 6 Different configurations shown. Figure 6 Each component shown in the figure can be implemented by hardware, software or a combination thereof.

[0113] In another embodiment, the electronic device may be a satellite base station, and the gateway may be wirelessly connected to the satellite base station. The satellite base station may also connect to or transmit and receive information with the Evolved Universal Terrestrial Radio Access (E-UTRA) system, new wireless systems, future wireless access systems, or WiFi systems defined in the 3rd Generation Partnership Project (3GPP). The satellite base station may also connect to devices in two or more of the aforementioned wireless access systems. The satellite base station may also connect to an Open Radio Access Network (O-RAN).

[0114] Satellite base stations may be equipped with modules for implementing base station functions. These modules can implement the functions of the following devices: base station, evolved NodeB (eNodeB or eNB), transmission reception point (TRP), next-generation NodeB (gNB) in 5G mobile communication systems, next-generation base stations in 6th-generation (6G) mobile communication systems, base stations in future mobile communication systems, or access nodes in Wi-Fi systems.

[0115] The aforementioned satellite base station may also include an antenna and a transceiver. On the uplink, uplink signals from the gateway are received via the antenna, modulated by the transceiver, and further processed by the processor 310 to recover the signaling information sent by the gateway. On the downlink, signaling messages are processed by the processor 310 and modulated by the transceiver to generate downlink signals, which are transmitted to the gateway via the antenna. The processor 310 is further configured to execute the uplink synchronization method described in the above embodiment. The satellite base station may include a macro base station, a micro base station, an indoor base station, a relay node, or a donor node.

[0116] It can be understood that the above only introduces a simplified design of the base station. In actual applications, the base station may include any number of transmitters, receivers, processors, controllers, memories, communication units, etc., and all base stations that can implement this application are within the scope of protection of this application.

[0117] An embodiment of the present application provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the method process executed by the electronic device in the above method embodiment is executed.

[0118] This embodiment discloses a computer program product, which includes a computer program stored on a non-transitory computer-readable storage medium. The computer program includes program instructions. When the program instructions are executed by a computer, the computer can perform the methods provided in the above method embodiments, for example, including: measuring an uplink timing deviation of an uplink signal sent by the gateway through the feed beam, wherein the uplink timing deviation is a deviation between an arrival time of the uplink signal and an expected time; The uplink frame timing of the satellite base station is adjusted according to the uplink timing deviation.

[0119] In summary, the embodiments of the present application provide an uplink synchronization method, apparatus, electronic device, storage medium, and program product that adapt to the uplink delay deviation of a gateway by directly adjusting the uplink frame timing of a satellite base station, avoiding the drawbacks of traditional methods that frequently send TA commands to the gateway. This not only significantly reduces downlink signaling overhead and improves downlink resource utilization, but also mitigates the risk of synchronization deviation caused by gateway calculation errors and delay variations. Furthermore, by adjusting the base station side, reliance on gateway-side adjustments is reduced, while also avoiding synchronization failures caused by untimely or inaccurate gateway adjustments.

[0120] In the embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interface, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0121] In addition, the units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0122] Furthermore, the functional modules in each embodiment of the present application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0123] In this document, relational terms such as first and second, etc. are used merely to distinguish one entity or operation from another entity or operation, but do not necessarily require or imply any actual relationship or order between these entities or operations.

[0124] The above description is merely an embodiment of the present application and is not intended to limit the scope of protection of the present application. For those skilled in the art, various modifications and variations of the present application are possible. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. An uplink synchronization method, characterized in that: Applied to a satellite base station, where one feed beam of the satellite base station is connected to only one gateway, the method includes: measuring an uplink timing deviation of an uplink signal sent by the gateway through the feed beam, wherein the uplink timing deviation is a deviation between an arrival time of the uplink signal and an expected time; The uplink frame timing of the satellite base station is adjusted according to the uplink timing deviation.

2. The method according to claim 1, characterized in that The adjusting the uplink frame timing of the satellite base station according to the uplink timing deviation includes: If the uplink timing deviation is delayed by a first duration, adjusting the uplink frame timing of the satellite base station to delay by the first duration; If the uplink timing deviation is advanced by the second time period, the uplink frame timing of the satellite base station is adjusted to advance by the second time period.

3. The method according to claim 1, characterized in that After measuring the uplink timing deviation of the uplink signal sent by the gateway through the feed beam, the method further includes: When the uplink timing deviation exceeds a set threshold, a TA instruction is sent to the gateway, where the TA instruction includes the uplink timing deviation.

4. The method according to claim 1, wherein The adjusting the uplink frame timing of the satellite base station according to the uplink timing deviation includes: The uplink frame timing of the satellite base station is adjusted according to the uplink timing deviation in accordance with an adjustment period, wherein the uplink timing deviation is measured at a time closest to the adjustment period.

5. The method according to claim 4, characterized in that The adjustment period is determined according to the elevation angle of the satellite where the satellite base station is located, and the adjustment period is positively correlated with the elevation angle.

6. The method according to claim 5, characterized in that The adjustment period is determined by: Calculating a bilateral delay variation rate between the satellite and the gateway according to the orbital altitude and elevation angle of the satellite; An adjustment period is calculated according to the maximum allowable delay deviation and the bilateral delay change rate.

7. The method according to claim 6, characterized in that The maximum allowable delay deviation is determined by: Obtaining the CP length configured by the satellite base station; The maximum allowable delay deviation is determined according to the CP length.

8. The method according to claim 5, characterized in that The adjustment period is determined by: The current adjustment period is determined according to a pre-configured mapping relationship between the elevation angle and the adjustment period.

9. An uplink synchronization device, characterized in that: Applied to a satellite base station, where one feed beam of the satellite base station is connected to only one gateway, the device comprises: a deviation measurement module, configured to measure an uplink timing deviation of an uplink signal sent by the gateway via the feed beam, the uplink timing deviation being a deviation between an arrival time of the uplink signal and an expected time; A timing adjustment module is used to adjust the uplink frame timing of the satellite base station according to the uplink timing deviation.

10. An electronic device, characterized in that: The method comprises a processor and a memory, wherein the memory stores computer-readable instructions. When the computer-readable instructions are executed by the processor, the method according to any one of claims 1 to 8 is executed.

11. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method according to any one of claims 1 to 8 is executed.

12. A computer program product, characterized in that The method comprises computer program instructions, and when the computer program instructions are read and executed by a processor, the method according to any one of claims 1 to 8 is executed.

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