Cell switching method, electronic equipment, chip system and storage medium

Abstract

The invention provides a cell switching method, electronic equipment, a chip system and a storage medium, and relates to the technical field of electronic equipment, in a condition switching scene, user equipment sends a motion route to a source node and a core network in advance, and the core network can determine a along-line base station according to the motion route, so as to switch a cell according to the along-line base station. A source node can determine the base stations along the line within a certain distance from the current position of user equipment as candidate base stations of the current position from the base stations along the line determined by a core network, and the source node determines that the user equipment uses CHO according to the state of the user equipment. The configuration information of each candidate base station, a position switching condition and a signal switching condition are issued to the user equipment, the user equipment firstly judges whether the candidate base station meets the position switching condition, if yes, whether the signal switching condition is met or not is continued, and if not, the user equipment sends the configuration information of each candidate base station to the user equipment. And switching to one base station meeting the two types of conditions at the same time. According to the switching mode, the phenomena of ping-pong switching and switching failure can be reduced.

Description

Technical Field

[0001] The present application relates to the technical field of electronic equipment, and in particular to a cell switching method, electronic equipment, a chip system, and a storage medium. Background Art

[0002] The 3rd Generation Partnership Project (3GPP) introduced a new handover procedure: Conditional Handover (CHO). This procedure allows the user equipment to autonomously switch serving cells when one or more execution conditions are met. However, ping-pong handovers and handover failures are common in current CHO scenarios. Summary of the Invention

[0003] The present application provides a cell switching method, electronic device, chip system and storage medium, which can reduce the phenomenon of ping-pong switching and switching failure.

[0004] To achieve the above objectives, the first aspect of the present application provides a cell handover method, which adopts the following technical solutions: The user equipment receives reset information sent by the first base station, where the reset information includes information of the second base station and a CHO execution condition, where the first base station is a base station currently providing cell services for the user equipment, the second base station is a candidate base station for the user equipment at a current location, and the CHO execution condition includes a location switching condition and a signal switching condition; Acquiring, by the user equipment, a first distance between the predicted position of the user equipment and the second base station; Acquiring, by the user equipment, a quality parameter of a signal of the second base station received by the user equipment; The user equipment determines that there is a fourth base station among the second base stations, the first distance of which satisfies the position switching condition and the quality parameter of which satisfies the signal switching condition; The user equipment is handed over to the fourth base station.

[0005] In the present application, by setting the location switching condition and the signal switching condition in the CHO execution condition, and the location switching condition is related to the predicted position of the user equipment, the target base station (i.e., the fourth base station) screened out from the candidate base stations (i.e., the second base station) can be closer to the predicted position of the user equipment and have a better signal, thereby increasing the success rate of switching to the target base station and reducing the ping-pong switching phenomenon due to location restrictions.

[0006] As an implementation of the first aspect of the present application, before the user equipment obtains the quality parameter of the signal received from the second base station, the method further includes: The user equipment determines that there is a third base station among the second base stations, the third base station having the first distance meeting the location switching condition; Correspondingly, the user equipment acquiring the quality parameter of the signal received from the second base station includes: Acquiring, by the user equipment, a quality parameter of a signal of the third base station received by the user equipment; The user equipment determines that there is a fourth base station among the second base stations, the first distance of which satisfies the position switching condition and the quality parameter of which satisfies the signal switching condition, including: The user equipment determines that there is a fourth base station among the third base stations, whose quality parameter meets the signal switching condition.

[0007] In this application, since the monitoring period of the signal quality parameters is required to be high and the power consumption is large, the position switching conditions can be judged first. When there are candidate base stations that meet the position switching conditions, the signal quality parameters of these candidate base stations that meet the position switching conditions are monitored, thereby reducing power consumption.

[0008] As another implementation method of the first aspect of the present application, the second base station is a base station whose vertical distance to the first section is within a second distance, and the first section is the section on the movement route of the user equipment from the current position of the user equipment to a third distance ahead.

[0009] In this application, in order to reduce the number of candidate base stations, the base stations within the second distance (circle the candidate base stations at a certain distance along the movement route) in the vertical distance of the user equipment's movement route and within the third distance in front of the user equipment (circle the candidate base stations within a certain distance in front of the user equipment) can be limited. By limiting these two distances, on the one hand, the base stations that meet the CHO execution conditions can be reduced, and on the other hand, the base stations behind the user equipment's movement route are deleted by limiting the front of the user equipment's movement route, thereby reducing the phenomenon of ping-pong switching.

[0010] As another implementation of the first aspect of the present application, before the user equipment receives the reset information sent by the first base station, the method further includes: The user equipment sends the movement route of the user equipment to the first base station, and the movement route is used to instruct the core network to determine the base stations along the movement route. The movement route is also used to instruct the first base station to determine the candidate base stations of the user equipment at its current location from the base stations along the route.

[0011] In this application, since it is necessary to use the distance between the predicted position of the user equipment and the candidate base station to determine whether the position switching condition is met, it is necessary to pre-determine the movement route of the user equipment so that the predicted position of the user equipment can be obtained more accurately, and the candidate base station can be determined more accurately through the movement route, thereby avoiding filtering out some candidate base stations that may be closer through the position switching condition, and avoiding filtering out some candidate base stations that are farther away.

[0012] As another implementation of the first aspect of the present application, before the user equipment obtains the first distance between the predicted position of the user equipment and the second base station, the method further includes: The user equipment obtains, by an inertial navigation system carried by the user equipment, motion parameters of the user equipment according to a sampling period; The user equipment obtains a predicted position of the user equipment in a next sampling period according to the motion parameter and the current position of the user equipment.

[0013] In this application, the user device itself is required to carry an inertial navigation system. The inertial navigation system can collect the user device's motion parameters. The motion parameters collected by the inertial navigation system can be used to obtain the user device's predicted position. Because the inertial navigation system itself needs to collect some data at a specific period, the data collected by the inertial navigation system can be used to obtain the predicted position without increasing additional power consumption.

[0014] As another implementation of the first aspect of the present application, the user equipment obtaining, by an inertial navigation system carried by the user equipment according to a sampling period, the motion parameters of the user equipment includes: The user equipment obtains, by means of an inertial navigation system carried by the user equipment, multiple sets of motion parameters of the user equipment according to a sampling step within a sampling period; Accordingly, the user equipment obtains a predicted position of the user equipment in the next sampling period according to the motion parameter and the current position of the user equipment, including: The user equipment obtains a predicted motion trajectory of the user equipment based on multiple sets of motion parameters of the user equipment acquired according to a sampling step within a sampling period, where the predicted motion trajectory includes a predicted position of the user equipment in a next sampling period.

[0015] In this application, when obtaining the predicted position of the user device, multiple continuous sampling data are required to obtain the predicted position of the user device more accurately. Therefore, the sampling period can be set as the period for obtaining the predicted position. In order to obtain the predicted position in the next sampling period, the sampling step can be set in the previous sampling period, thereby obtaining multiple groups of motion parameters sorted by time in the previous sampling period, and the predicted position is obtained based on these multiple groups of motion parameters sorted by time.

[0016] As another implementation of the first aspect of the present application, the inertial navigation system includes: an accelerometer and a gyroscope; the motion parameters of the user equipment include: a motion speed and a motion acceleration of the user equipment; The user equipment obtains, according to the motion parameter and the current position of the user equipment, a predicted position of the user equipment in a next sampling period, including: The user equipment obtains a predicted travel distance of the user equipment until a next sampling period according to the movement speed, movement acceleration and sampling period of the user equipment; The user equipment obtains a predicted position of the user equipment in a next sampling period according to the movement route of the user equipment and the predicted travel distance.

[0017] In this application, to further reduce power consumption, the user device's predicted distance within a sampling period can be calculated using the speed, acceleration, and sampling period obtained by the inertial navigation system. This predicted distance can then be extended forward along the user device's trajectory to represent the predicted position for the next sampling period. This prediction method has slightly lower accuracy, but also lower power consumption, making it suitable for scenarios with strict power requirements.

[0018] As another implementation of the first aspect of the present application, the user equipment determining that there is a third base station in the second base station whose first distance satisfies the location switching condition includes: The user equipment determines that there is a third base station among the second base stations, the first distance of which is smaller than the coverage radius of the second base station.

[0019] In the present application, whether the location switching condition is met can be determined by whether the predicted location of the user equipment is within the coverage radius of the candidate base station.

[0020] As another implementation of the first aspect of the present application, the user equipment determining that there is a fourth base station among the third base stations whose quality parameter meets the signal switching condition includes: Determining, by the user equipment, that there is a fourth base station among the third base stations, the fourth base station having a higher signal quality than the first base station; Or, the user equipment determines that there is a fourth base station among the third base stations, the signal quality of which is higher than the first value; Alternatively, the user equipment determines that among the third base stations, there is a fourth base station whose signal quality is higher than the first value and whose signal quality is higher than the first base station.

[0021] In the present application, the signal switching condition can compare the signal quality of the third base station itself with a fixed value to determine whether the signal switching condition is met, or it can compare the signal quality of the third base station itself with the signal quality of the source base station to determine whether the signal switching condition is met. Of course, both situations can be considered at the same time. When the signal quality itself is higher than the fixed value and higher than the signal quality of the source base station, it is determined that the signal switching condition is met.

[0022] As another implementation of the first aspect of the present application, handing over, by the user equipment, to the fourth base station includes: The user equipment determines a base station with the highest signal quality among the fourth base stations as a target base station; Alternatively, the user equipment determines a base station among the fourth base stations that has the smallest first distance to the predicted location of the user equipment as the target base station; Alternatively, the user equipment determines one of the fourth base stations as the target base station based on a signal quality of each base station in the fourth base stations and a first distance between the base station and the predicted location of the user equipment; The user equipment is handed over to the target base station.

[0023] In this application, when there are multiple candidate base stations that meet both the location switching conditions and the signal switching conditions, the base station with the highest signal quality or the base station closest to the predicted position can be selected, and the optimal base station can be determined by considering both signal quality and distance parameters.

[0024] As another implementation of the first embodiment of the present application, the quality parameter includes: at least one of: reference signal received power, reference signal received quality, and signal to interference plus noise ratio; the signal quality is a weighted sum of the quality parameters.

[0025] In the present application, the signal quality can be determined based on multiple signal quality parameters, so that a base station with the highest comprehensive quality is obtained as the target base station for switching.

[0026] As another implementation of the first aspect of the present application, the method further includes: Before starting to move along the movement route, or within a first period of time after starting to move along the movement route, the user equipment sends the movement route to a base station currently providing cell service for the user equipment.

[0027] In this application, since the candidate base stations determined in the CHO execution conditions are determined based on the movement path, the movement path of the user device must be acquired in advance. In addition, the predicted position is also related to the movement path, so the movement path of the user device must also be acquired in advance. Of course, if the movement path of the user device is disrupted, it must be promptly transmitted to the currently connected base station and core network.

[0028] As another implementation of the first aspect of the present application, after the user equipment is switched to the fourth base station, the method further includes: The user equipment forwards the movement route to the fourth base station through the first base station; Alternatively, the user equipment sends the movement route to the fourth base station.

[0029] In this application, after switching the base station, the movement route needs to be sent to the latest connected base station in a timely manner so that the latest connected base station can determine the candidate base station.

[0030] As another implementation of the first aspect of the present application, the user equipment obtaining the quality parameter of the signal of the third base station received by the user equipment includes: The user equipment monitors, within a current sampling period, a quality parameter of a signal of the third base station according to a monitoring period, where the current sampling period is a sampling period corresponding to the predicted position; Correspondingly, the user equipment determining that there is a fourth base station among the third base stations whose quality parameter satisfies the signal switching condition includes: Before the current sampling period ends, the user equipment determines that there is a fourth base station among the third base stations whose quality parameter meets the signal switching condition.

[0031] In this application, the period for predicting a position can also be set to be greater than the signal monitoring period, so that there can be multiple opportunities to determine the target base station when determining the target base station once. In this way, although the user equipment is constantly moving, the probability of successful switching is also increased.

[0032] In a second aspect, an electronic device is provided, comprising a processor, wherein the processor is configured to call a computer program stored in a memory to implement the steps in any one of the methods of the first aspect of the present application.

[0033] In a third aspect, a chip system is provided, comprising a processor coupled to a memory, wherein the processor executes a computer program stored in the memory so that the electronic device implements the steps in any one of the methods of the first aspect of the present application.

[0034] In a fourth aspect, a computer-readable storage medium is provided, which stores a computer program. When the computer program runs on an electronic device, the electronic device implements the steps of any one of the methods in the first aspect of the present application.

[0035] In a fifth aspect, a computer program product is provided. When the computer program product is run on a device, the electronic device executes the steps of any one of the methods in the first aspect of the present application.

[0036] It can be understood that the beneficial effects of the second to fifth aspects mentioned above can be found in the relevant description of the first aspect mentioned above, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 A schematic diagram of the hardware structure of an electronic device provided in an embodiment of the present application; Figure 2 A cell switching timing diagram using CHO is provided in an embodiment of the present application; Figure 3 A schematic diagram of a process for obtaining motion parameters of a user device by an inertial navigation system provided in an embodiment of the present application; Figure 4 A schematic diagram of a process for obtaining a predicted location of a user equipment provided in an embodiment of the present application; Figure 5 A schematic diagram of a core network determining base stations along a movement route provided in an embodiment of the present application; Figure 6 A schematic diagram of another method for a core network to determine base stations along a movement route provided in an embodiment of the present application; Figure 7 A schematic diagram of a source base station determining a candidate base station for a user equipment at its current location provided by an embodiment of the present application; Figure 8 A schematic diagram of the positional relationship between the current position, predicted position, source base station, and candidate base stations of a user equipment provided in an embodiment of the present application; Figure 9 A schematic diagram of the positional relationship between the current position, predicted position, source base station, and candidate base stations of a user equipment provided in an embodiment of the present application; Figure 10 A schematic diagram of the positional relationship between the current position, predicted position, source base station, and candidate base stations of a user equipment provided in an embodiment of the present application; Figure 11 A schematic diagram of the positional relationship between the current position, predicted position, source base station, and candidate base stations of a user equipment provided in an embodiment of the present application; Figure 12A schematic diagram of a user equipment according to an embodiment of the present application determining whether a candidate base station meets a signal switching condition; Figure 13 Another cell switching timing diagram using CHO is provided in an embodiment of the present application. DETAILED DESCRIPTION

[0038] In the following description, specific details such as specific system structures and technologies are provided for illustration rather than limitation to facilitate a thorough understanding of the embodiments of the present application. However, it should be clear to those skilled in the art that the present application may also be implemented in other embodiments without these specific details.

[0039] It should be understood that when used in the present specification and the appended claims, the term "comprising" indicates the presence of described features, integers, steps, operations, elements and / or components, but does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or collections thereof.

[0040] It should also be understood that in the embodiments of this application, "one or more" refers to one, two, or more than two; "and / or" describes the relationship between associated objects, indicating that three relationships can exist; for example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone, where A and B can be singular or plural. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0041] In addition, in the description of this application specification and the appended claims, the terms "first", "second", "third", "fourth", etc. are only used to distinguish the descriptions and cannot be understood as indicating or implying relative importance.

[0042] References to "one embodiment" or "some embodiments" in this specification mean that a particular feature, structure, or characteristic described in conjunction with that embodiment is included in one or more embodiments of the present application. Thus, phrases such as "in one embodiment," "in some embodiments," "in other embodiments," and "in other embodiments" appearing in various places in this specification do not necessarily refer to the same embodiment, but rather mean "one or more but not all embodiments," unless otherwise specifically emphasized. The terms "including," "comprising," "having," and variations thereof all mean "including but not limited to," unless otherwise specifically emphasized.

[0043] The present application provides a cell handover method that can be applied to intelligent entities capable of high-speed movement, such as vehicles and drones. Of course, it can also be applied to electronic devices mounted on or carried by these intelligent entities. These electronic devices can include portable tablets, mobile phones, wearable devices, laptops, ultra-mobile personal computers (UMPCs), netbooks, personal digital assistants (PDAs), and the like. They can also be engineering machines installed on intelligent entities. The present application does not limit the specific types of intelligent entities and electronic devices. Of course, intelligent entities themselves are also considered electronic devices.

[0044] Figure 1 The electronic device 100 may include a processor 110, an external memory interface 120, an internal memory 121, a universal serial bus (USB) interface 130, a charging management module 140, a power management module 141, a battery 142, an antenna 1, an antenna 2, a mobile communication module 150, a wireless communication module 160, an audio module 170, a speaker 170A, a receiver 170B, a microphone 170C, an earphone interface 170D, a sensor module 180, a button 190, a motor 191, an indicator 192, a camera 193, a display 194, and a subscriber identification module (SIM) card interface 195. The sensor module 180 may include a pressure sensor 180A, a gyroscope sensor 180B, an air pressure sensor 180C, a magnetic sensor 180D, an acceleration sensor 180E, a distance sensor 180F, a proximity light sensor 180G, a fingerprint sensor 180H, a temperature sensor 180J, a touch sensor 180K, an ambient light sensor 180L, a bone conduction sensor 180M, etc.

[0045] It should be understood that the structures illustrated in the embodiments of the present application do not constitute a specific limitation on the electronic device 100. In other embodiments of the present application, the electronic device 100 may include more or fewer components than shown, or may combine or separate certain components, or arrange the components differently. The illustrated components may be implemented in hardware, software, or a combination of software and hardware.

[0046] The processor 110 may include one or more processing units. For example, the processor 110 may include an application processor (AP), a modem processor, a graphics processing unit (GPU), an image signal processor (ISP), a controller, a memory, a video codec, a digital signal processor (DSP), a baseband processor, and / or a neural-network processing unit (NPU). The different processing units may be independent devices or integrated into one or more processors.

[0047] Processor 110 may also include a memory for storing instructions and data. In some embodiments, the memory in processor 110 is a cache memory. This memory can store instructions or data that have just been used or are being recycled by processor 110. If processor 110 needs to use the same instruction or data again, it can directly retrieve it from the memory. This avoids duplicate accesses, reduces processor 110 latency, and thus improves system efficiency.

[0048] Internal memory 121 can be used to store computer-executable program code, which includes instructions. Processor 110 executes the instructions stored in internal memory 121 to execute various functional applications and data processing functions of electronic device 100. Internal memory 121 may include a program storage area and a data storage area. The program storage area may store an operating system and at least one application required for a function (such as image playback).

[0049] The touch sensor 180K is also called a "touch panel." The touch sensor 180K can be disposed on the display screen 194. The touch sensor 180K and the display screen 194 form a touch screen, also called a "touch screen." The touch sensor 180K is used to detect touch operations applied thereto or in the vicinity thereof. The touch sensor can transmit the detected touch operations to the application processor to determine the type of touch event. Visual output related to the touch operations can be provided via the display screen 194. In other embodiments, the touch sensor 180K can also be disposed on the surface of the electronic device 100, in a location different from that of the display screen 194.

[0050] Electronic device 100 implements display functionality through a GPU, display screen 194, and an application processor. A GPU is a microprocessor for image processing that connects display screen 194 and the application processor. The GPU is used to perform mathematical and geometric calculations for graphics rendering. Processor 110 may include one or more GPUs that execute program instructions to generate or modify display information.

[0051] Display screen 194 is used to display images, videos, and the like. Display screen 194 includes a display panel. The display panel can be a liquid crystal display (LCD), an organic light-emitting diode (OLED), an active-matrix organic light-emitting diode (AMOLED), a flexible light-emitting diode (FLED), a MiniLED, a MicroLED, a Micro-OLED, or a quantum dot light-emitting diode (QLED). In some embodiments, electronic device 100 may include one or N display screens 194, where N is a positive integer greater than one.

[0052] The camera 193 is used to capture still images or videos. The object generates an optical image through the lens and projects it onto the photosensitive element. The photosensitive element can be a charge coupled device (CCD) or a complementary metal-oxide-semiconductor (CMOS) phototransistor. The photosensitive element converts the light signal into an electrical signal, and then passes the electrical signal to the ISP for conversion into a digital image signal. The ISP outputs the digital image signal to the DSP for processing. The DSP converts the digital image signal into an image signal in a standard RGB, YUV or other format. In some embodiments, the electronic device 100 may include 1 or N cameras 193, where N is a positive integer greater than 1.

[0053] The embodiments of the present application do not particularly limit the specific structure of the execution subject of the cell switching method, as long as the code recording the cell switching method of the embodiments of the present application can be executed to communicate according to the cell switching method provided by the embodiments of the present application. For example, the execution subject of the cell switching method provided by the embodiments of the present application can be a functional module in an electronic device that can call and execute a program, or a communication device used in an electronic device, such as a chip.

[0054] With the rapid development of mobile communications, the demand for communications in high-speed mobile scenarios such as highways, high-speed railways, and drones is also increasing. For example, 5G mobile communication technology can provide a practical platform for vehicle networks, intelligent transportation, smart cities, etc.

[0055] However, compared to 4G mobile communication technology, 5G mobile communication technology has a smaller coverage radius and an increased number of base stations. Therefore, in high-speed mobility scenarios, the high-speed movement of connected user devices (such as vehicles and drones) will result in frequent switching of serving cells. Therefore, to maintain high-quality transmission of user device communication signals in high-speed mobility scenarios, it is necessary to improve the user device's handover success rate and communication quality.

[0056] The 3rd Generation Partnership Project (3GPP) introduced a new handover procedure: Conditional Handover (CHO), which means that the user equipment autonomously switches the serving cell when one or more execution conditions are met.

[0057] Specifically, the node providing cell service (e.g., base station, satellite, etc.) decides whether to use CHO and sends the configuration information and switching conditions of each candidate node to the user equipment when using CHO. The user equipment evaluates whether there is a candidate node that meets the switching conditions. If there is a candidate node that meets the switching conditions, the user equipment switches to the candidate node that meets the switching conditions based on the configuration information of the candidate node. The candidate node that is switched to provides cell service for the user equipment.

[0058] Reference Figure 2 , is a conditional handover sequence diagram provided in an embodiment of the present application. Conditional handover includes three phases: handover preparation, handover execution, and handover completion. B1 to B4 are the handover preparation phase, used to prepare for CHO handover; B5 to B10 are the handover execution phase, during which the user equipment switches from the source node to candidate node 1; and B11 is the handover completion phase, used to notify other candidate nodes to cancel the handover.

[0059] A1: User equipment sends user data 1 to the source node currently providing cell service.

[0060] A2: After receiving user data 1 sent by the user equipment, the source node sends user data 1 to the core network UPF.

[0061] In the embodiments of the present application, user devices can collect user data, which needs to be uploaded to the core network to implement certain functions based on this user data. For example, image data collected by a drone needs to be uploaded to the core network through a source node to implement certain functions based on the image data; vehicle speed, environmental information, etc. collected by a vehicle needs to be uploaded to the core network through a source node to implement intelligent driving based on the information collected by the vehicle.

[0062] The above user data and usage of the user data are for example purposes only. In actual applications, there are no restrictions on the user data that the user equipment needs to upload to the core network, the functions of the user data, and the timing of uploading the user data.

[0063] B1. The user equipment sends signal measurement data to the source node.

[0064] In this embodiment of the present application, a source node configures measurement parameters for a user device. The user device can perform measurements based on the measurement parameters configured by the source node, thereby obtaining measurement data. The measurement data is used to determine whether the user device uses CHO. The measurement parameters may include signal strength, signal power, and other signal-related parameters.

[0065] B2. After receiving the signal measurement data, the source node determines that the user equipment uses CHO according to the signal measurement data.

[0066] In the embodiment of the present application, a condition for the user equipment to use CHO may be preset, and the measurement parameters configured for the user equipment may be determined based on the condition for the user equipment to use CHO.

[0067] As an example scenario, when a user device moves at high speed, its position and direction are likely to change significantly in a short period of time due to its high speed. However, the traditional switching process takes a long time to prepare, and the signal quality between the user device and the source node may be very unstable before the actual switching, resulting in switching failure.

[0068] Therefore, in an embodiment of the present application, the source node needs to send the signal measurement data to the source node, and the source node determines in advance whether the user equipment is CHO based on the signal measurement data. If it is determined to use CHO, the CHO execution conditions are configured to the user equipment in advance, so that the user equipment can autonomously monitor the data related to the CHO execution conditions.

[0069] B3: When the source node determines that the user equipment uses CHO, it sends a CHO request to each candidate node.

[0070] In the embodiment of the present application, each candidate node includes candidate node 1 and other candidate nodes i (i is greater than or equal to 2). Of course, in actual applications, if the location is in a mountainous area where base stations are sparsely distributed, the candidate node may only include one. The embodiment of the present application does not limit the total number of candidate nodes.

[0071] B4: The source node receives the CHO responses sent by each candidate node.

[0072] In the embodiment of the present application, after receiving a CHO request from a source node, each candidate node sends a CHO response to the source node. The CHO response contains its own configuration information. The configuration information is the parameters used by the user equipment and the candidate node to establish an RRC connection. For example, the user equipment needs to select a bandwidth, power level, and modulation mode that matches the candidate node to establish an RRC connection with the candidate node. Of course, the configuration information of different candidate nodes is different, so each candidate node sends its own configuration information to the source node.

[0073] B5. After receiving the CHO responses sent by each candidate node, the source node sends a CHO reset message to the user equipment, carrying the configuration information of each candidate node and the signal switching condition.

[0074] In the embodiment of the present application, the CHO reset information is used to send RRC reconfiguration information to the user equipment.

[0075] B6. After receiving the CHO reset information, the user equipment stores the configuration information of each candidate node and sets the CHO switching condition to the received signal switching condition.

[0076] B7, after storing the configuration information of each candidate node and setting the switching condition of the CHO to the received signal switching condition, the user equipment sends a reset information to the source node.

[0077] B8, the user equipment evaluates that the candidate node 1 meets the signal switching condition.

[0078] B9 , when the candidate node 1 meets the signal switching condition, the user equipment switches to the candidate node 1 according to the configuration information of the candidate node 1 .

[0079] In an embodiment of the present application, one or more signal switching conditions may be set. If any candidate node satisfies any signal switching condition, the node is switched to any candidate node that satisfies any signal switching condition. Of course, the node with the best signal quality among multiple candidate nodes that satisfy any signal switching condition may also be selected as the target node to be switched to.

[0080] A signal switching condition may involve at least one signal-related measurement parameter, such as reference signal received power (RSRP), reference signal received quality (RSRQ), and signal to interference plus noise ratio (SINR).

[0081] Of course, in practical applications, a signal switching condition may involve two or more of the aforementioned signal-related measurement parameters. For example, a signal switching condition may involve reference signal received power (RSRP) and reference signal received quality (RSRQ), or reference signal received power (RSRP) and signal to interference plus noise ratio (SINR).

[0082] A numerical range or a level range may be set for the measurement parameters involved. When the user equipment determines that the measurement parameters of the received signal of the candidate node 1 are within the numerical range or the level range, it indicates that the candidate node 1 meets the signal switching condition.

[0083] B10, after the user equipment is successfully switched to the candidate node 1, the candidate node 1 sends a switching success message to the source node.

[0084] B11, after receiving the handover success message sent by candidate node 1, the source node sends a handover cancellation message to other candidate nodes i.

[0085] In addition, in the process of the user equipment switching the serving cell, if early user data forwarding is applied, then after the handover is successful, the source node needs to forward the stored user data 1 to the candidate node 1.

[0086] C1, after receiving the handover success message sent by candidate node 1, the source node sends user data 1 to candidate node 1.

[0087] After the user equipment successfully switches the serving cell, subsequent user data 2 is sent to the switched candidate node 1 and then sent to the core network through the candidate node 1.

[0088] D1: After successfully switching to candidate node 1, the user equipment sends user data 2 to candidate node 1.

[0089] D2, the candidate node serves as the serving cell of the user equipment, and after receiving the user data 2, sends the user data 2 to the core network.

[0090] It can be understood that in the CHO process, the source node can send CHO reset information to the user equipment based on the signal measurement data transmitted by B1 before the user equipment receives the signal quality of the source node deteriorating. Therefore, the user equipment does not need to wait for the switching instruction sent by the source node. Instead, after storing the configuration information and signal switching conditions of each candidate node, it can independently evaluate whether the configured CHO switching conditions are met, and perform switching when the configured CHO switching conditions are met (at this time, the signal of the source node may have deteriorated for the user equipment); thereby reducing the switching delay, reducing the signaling load, and improving the switching success rate, so that the user equipment is always under the service of the node with higher signal quality. Therefore, CHO is suitable for high-speed mobile scenarios.

[0091] As mentioned above, the parameters involved in the signal switching conditions in the CHO switching conditions are all measurement parameters related to the signal quality. The above measurement parameters have high requirements on the measurement period and monitoring performance of the user equipment. In addition, since the measurement parameters related to the signal are used as the switching conditions, if you switch to a candidate node, you may switch back to the source node later, which may easily lead to ping-pong switching. If only the switching conditions related to the signal are considered, switching failure is also likely to occur.

[0092] The embodiment of the present application can add a position switching condition to the above-mentioned CHO switching condition, that is, the CHO switching condition includes a signal switching condition and a position switching condition. On the basis of the existence of candidate nodes that meet the position switching condition, the measurement parameters of the candidate nodes that meet the position switching condition are monitored, thereby determining the target node that meets the signal switching condition. Since the measurement parameters of the candidate nodes that meet the position switching condition are monitored only on the basis of the existence of candidate nodes that meet the position switching condition, the target nodes that ultimately meet the switching condition can be reduced, thereby reducing the phenomenon of ping-pong switching; at the same time, some candidate nodes that do not meet the position conditions are excluded, thereby reducing the phenomenon of switching failure.

[0093] Of course, in practical applications, it is also possible to monitor the predicted positions of candidate nodes that meet the signal switching conditions based on the existence of candidate nodes that meet the signal switching conditions, thereby determining the target node that meets the position switching conditions.

[0094] The subsequent embodiments of this application take the example of first determining whether the position switching condition is met and then determining whether the signal switching condition is met.

[0095] The position switching condition among the CHO switching conditions is described in detail below.

[0096] User devices such as vehicles or drones are usually equipped with an inertial navigation system for positioning and navigation. The inertial navigation system is a navigation system that uses an inertial measurement unit to measure the state of motion. Among them, the inertial measurement unit includes but is not limited to accelerometers, gyroscopes, etc., and the measured state of motion includes but is not limited to position, speed, and attitude. The inertial measurement unit is a device that needs to be used on user devices such as vehicles or drones and has a high detection frequency. Therefore, its application in the cell switching method does not cause additional large power consumption. In addition, the inertial navigation system can be an inertial navigation system equipped on the vehicle, or it can be an inertial navigation system on an electronic device such as a mobile phone of a user on the vehicle. The inertial navigation system in the embodiment of the present application is a navigation system on an electronic device that moves along the motion route with the user device.

[0097] Reference Figure 3 , which is the process of measuring the position, speed and attitude of the user equipment by the inertial measurement unit in the inertial navigation system provided in the embodiment of the present application.

[0098] The accelerometer measures the acceleration of the moving carrier in all directions: linear acceleration and gravitational acceleration. In this process, the coordinate system of the user device is converted to the navigation coordinate system, and finally the speed and position are output through navigation calculation.

[0099] The angular velocity of the user device is measured by a gyroscope, and the angular velocity is integrated to obtain the attitude angle of the user device relative to the reference direction.

[0100] The above process of calculating position and speed may also be combined with data measured by a gyroscope, and the process of calculating attitude may also be combined with data measured by an accelerometer.

[0101] After obtaining the motion parameters of the user device through the inertial navigation system, it is also necessary to predict the subsequent position of the user device (i.e., the predicted position) based on the motion parameters of the user device. Figure 4 , which is a schematic diagram of the process of obtaining the predicted position of the user equipment by the inertial navigation system provided in an embodiment of the present application.

[0102] The accelerometer and gyroscope in the inertial measurement unit are sampled according to the sampling period, and the current position, speed, acceleration, attitude and other motion parameters of the user device are obtained based on the data sampled in the current sampling period.

[0103] A sampling period T for obtaining the predicted position can be set. Within the sampling period T, the inertial measurement unit can be used to sample multiple times, with a sampling step of a. That is, the inertial measurement unit samples according to the sampling step a, and each sampling can obtain a set of motion parameters of the user device.

[0104] Within a sampling period Ti, after multiple samplings (sampling step a), multiple sets (the number of sets is T / a) of motion parameters of the user device are obtained. Based on the multiple sets of motion parameters of the user device within the sampling period Ti, the predicted position of the user device in the sampling period T(i+1) is predicted.

[0105] In addition, it can be set that: the sampling step a is smaller than the frequency at which the user equipment monitors the signal measurement parameters of the candidate base stations, and the sampling period T is larger than the frequency at which the user equipment monitors the signal measurement parameters of the candidate base stations.

[0106] The embodiment of the present application does not limit the method of predicting positions with multiple sets of historical motion parameters.

[0107] In practical applications, the location of a user device can also be predicted using a relatively simple method. For example, the movement routes of vehicles, high-speed trains, and drones are typically predetermined. For example, when using vehicle navigation, a starting point and destination are required, and a route is planned based on these two locations. High-speed trains travel along planned routes, so their routes can also be predetermined. Some operational drones also follow pre-set routes, so the movement routes of user devices such as vehicles, high-speed trains, and drones are known. The user device can transmit the movement route to the core network via the source node as soon as it begins moving along the movement route. Of course, in some scenarios, if the user device changes its originally planned movement route, it also needs to be promptly transmitted to the core network via the currently connected source node to re-determine the candidate base station. Embodiments of the present application can predict the user device's position on the movement route after a period of time T based on the user device's current position, movement speed, acceleration, and other movement parameters obtained by the inertial measurement unit, as well as the movement route. Specifically, the user device's predicted travel distance is calculated using s = at + v, and the position on the user device's movement route that is a distance S forward from the current position is recorded as the user device's predicted position for the next sampling period.

[0108] If the predicted location of the user equipment is available, the distance between the user equipment and each candidate base station is used to determine whether the predicted location of the user equipment in the next sampling period is within the coverage of each candidate base station. If the predicted location of the user equipment in the previous sampling period is within the coverage of candidate base station 1, then candidate base station 1 meets the location switching condition.

[0109] It can be understood that before determining whether there is a candidate base station that meets the position switching condition, it is necessary to determine the candidate base station.

[0110] Since the movement route of the user equipment can be known in advance, the candidate base stations along the movement route can be determined according to the movement route of the user equipment through the core network for communication with each base station.

[0111] Reference Figure 5 , is a schematic diagram of the process of determining candidate base stations provided in an embodiment of the present application.

[0112] The user equipment (UE) pre-transmits its movement route to the core network via the source node. The core network stores information about each base station (e.g., location information). The core network calculates the shortest distance from each base station along the movement route to the route. Base stations with a distance less than a distance threshold are identified as candidate base stations for the UE as it moves along the route.

[0113] Reference Figure 6 , is a schematic diagram of another process for determining candidate base stations provided in an embodiment of the present application.

[0114] The user equipment transmits the movement route to the core network through the source node in advance. The core network stores the information of each base station (for example, location information). Based on the movement route as the center line, the core network expands the distance threshold ( Figure 6 The two expansion lines shown in Figure 3) yield Figure 6 The two outer expansion lines shown define an area range, and base stations within the area range are candidate base stations for the user equipment during its movement along the movement route. Base stations outside the area range are not candidate base stations for the user equipment during its movement along the movement route.

[0115] In passing Figure 5 or Figure 6 After candidate base stations are determined, as the user device moves along its route, some candidate base stations, while located along the route, may be far from the current location and therefore do not meet the position switching conditions. Therefore, in practical applications, the source node can notify candidate base stations within a certain distance along the route.

[0116] Reference Figure 7 , which is a candidate base station related to the current location among the candidate base stations determined by the user equipment from the core network when the user equipment is at the current location provided in an embodiment of the present application.

[0117] The source base station determines a location (point S) on the user device's movement path that is S points away from the current location. Among the candidate base stations along the movement path determined by the core network, the base stations between the current location and point S are selected as candidate base stations for the current location. Of course, the source base station at the user device's current location is not considered a candidate base station for the current location.

[0118] Figure 7 Base stations 1 to 5 are candidate base stations when the user equipment is at its current location. Base stations 6 and 7 are not candidate base stations when the user equipment is at its current location, but may be candidate base stations when the user equipment moves to a predicted location.

[0119] Of course, if you follow Figure 6 The candidate base stations are determined in the manner shown, and two perpendicular lines can be drawn along the current position and point S. The base stations within the range of the two perpendicular lines and the two outer extension lines are the candidate base stations of the user equipment at the current position.

[0120] Based on the above description, it can be understood that the candidate base stations determined by the user equipment at the current location are: The base stations whose vertical distance to a segment of the user device's movement path, from the user device's current location to a point S ahead, is within a distance threshold. The value of S can be related to the distance between the user device's predicted location and the current location. For example, the value of S can be 2 or 3 times the distance. Of course, 2 and 3 are merely examples; other multiples can be used in actual applications.

[0121] When the candidate base stations at the current location of the user equipment can be determined, the distances between the predicted location of the user equipment and each candidate base station at the current location of the user equipment can be calculated, and the distances can be used to determine whether the predicted location of the user equipment is within the coverage of each candidate base station. For example, if the distance is less than the coverage radius of candidate base station 1, it indicates that the predicted location of the user equipment is within the coverage range of candidate base station 1. Correspondingly, if the distance is greater than or equal to the coverage radius of candidate base station 1, it indicates that the predicted location of the user equipment is not within the coverage range of candidate base station 1.

[0122] If the distance is less than the coverage radius of candidate base station 2, it indicates that the predicted location of the user equipment is within the coverage range of candidate base station 2. Correspondingly, if the distance is greater than or equal to the coverage radius of candidate base station 2, it indicates that the predicted location of the user equipment is not within the coverage range of candidate base station 2.

[0123] The coverage radius of different candidate base stations may be different. Each candidate base station may carry its own coverage radius in the configuration information of each base station, that is, transmit it to the source base station together with the CHO response, and then transmit it to the user equipment.

[0124] If the predicted location of the user equipment is within the coverage of the candidate base station, it means that the candidate base station meets the location switching condition. If the predicted location of the user equipment is not within the coverage of the candidate base station, it means that the candidate base station does not meet the location switching condition.

[0125] First, filter out the candidate base stations that meet the location switching conditions, and then determine whether there are target base stations that meet the signal switching conditions among these candidate base stations that meet the location switching conditions. If so, you can switch to the target base station that meets both the location switching conditions and the signal switching conditions.

[0126] When it is determined that there are multiple base stations that meet both the position switching condition and the signal switching condition, the base station may be switched to the base station with the best signal quality.

[0127] The quality of the signal can be determined by the measurement parameters in the signal switching condition. For example, a weighted sum of multiple measurement parameters can be taken, and the base station with the largest weighted sum of the measurement parameters is selected as the target base station to be switched.

[0128] Of course, the switch may also be made to a base station that is closest to the predicted location of the user equipment.

[0129] The signal quality can also be divided into several levels and assigned values ​​for different levels. The distance from the predicted location of the user device can also be divided into several levels and assigned values ​​for different levels. Weights can be assigned to the signal quality and distance, and the weighted sum of the signal quality and distance can be calculated, and the base station with the largest weighted sum can be switched to.

[0130] The embodiment of the present application does not limit the processing situation when there are multiple candidate base stations that simultaneously meet the location switching condition and the signal switching condition.

[0131] In practical applications, it is also possible to comprehensively consider the current location of the user equipment, the predicted location, and the location relationship between the source base station and the candidate base station to determine whether the candidate base station meets the location switching condition.

[0132] Reference Figure 8 , is the distance parameter in the location switching condition provided in the embodiment of the present application. The embodiment of the present application takes one of the candidate base stations i as an example.

[0133] Where d1 is the distance between the user device's current location and the source base station, d2 is the distance between the user device's predicted location and the source base station, d3 is the distance between the user device's current location and the candidate base station, and d4 is the distance between the user device's predicted location and the candidate base station. S1 is the coverage radius of the source base station, and Ti is the coverage radius of candidate base station i. These relationships are used to determine whether candidate base station i meets the location switching conditions.

[0134] Table 1 Several situations related to position switching conditions

[0135] Each case in Table 1 is described below.

[0136] Case 1: Reference Figure 8 , the current location of the user equipment is within the coverage of the source base station, the predicted location of the user equipment is within the coverage of the source base station, the current location of the user equipment is within the coverage of the candidate base station, and the predicted location of the user equipment is within the coverage of the candidate base station.

[0137] This indicates that both the user device's current location and predicted location are within the coverage of the candidate base station. If the user device does not switch, the quality of the signal received from the source base station will also be better when it moves to the predicted location. If the user device switches, the quality of the signal received from the candidate base station will also be better when it moves to the predicted location. Switching is possible or not. Of course, since the candidate base station is further ahead in the movement path, switching to it is also possible. Therefore, in case 1, the position switching condition is met.

[0138] In actual applications, additional conditions can also be added to Case 1: continue to determine whether the candidate base station meets the signal switching conditions. If the signal switching conditions are also met, compare the signal quality of the source base station received by the user equipment and the signal quality of the candidate base station. When the signal quality of the source base station is higher than the signal quality of the candidate base station by a certain value, or the signal quality of the source base station is higher than a specific value, the candidate base station is no longer regarded as a base station that meets both the position switching conditions and the signal switching conditions. This is because when the user equipment moves to the predicted position, the cell service provided by the source base station can also meet the requirements, so frequent switching of service cells is avoided.

[0139] Case 2: Reference Figure 8 , the current location of the user equipment is within the coverage of the source base station, the predicted location of the user equipment is within the coverage of the source base station, the current location of the user equipment is within the coverage of the candidate base station, and the predicted location of the user equipment is not within the coverage of the candidate base station.

[0140] This means that the current location and predicted location of the user device are both within the coverage of the source base station, but the predicted location is not within the coverage of the candidate base station. If the user device does not switch, the signal quality is guaranteed even if it moves to the predicted location. If the user device switches, it will not be able to establish a connection with the candidate base station when it moves to the predicted location. Therefore, it is best not to switch to the candidate base station. Therefore, in case 2, the location switching condition is not met.

[0141] Case 3: Reference Figure 9 , the current location of the user equipment is within the coverage of the source base station, the predicted location of the user equipment is within the coverage of the source base station, the current location of the user equipment is not within the coverage of the candidate base station, and the predicted location of the user equipment is within the coverage of the candidate base station.

[0142] This means that after the user device moves to the predicted location, it is within the coverage of the source base station and the candidate base station. If the user device does not switch, the signal is guaranteed when the user device moves to the predicted location. If the user device switches, the signal is guaranteed when the user device moves to the predicted location. Therefore, in this case, it can switch to the candidate base station or not. Of course, in actual applications, if the current location is not within the coverage of the candidate base station, it means that the candidate base station is closer to the front of the movement route, which is equivalent to switching to the base station in the forward direction. Therefore, case 3 meets the position switching condition.

[0143] Case 4: Reference Figure 9 , the current location of the user equipment is within the coverage of the source base station, the predicted location of the user equipment is within the coverage of the source base station, the current location of the user equipment is not within the coverage of the candidate base station, and the predicted location of the user equipment is not within the coverage of the candidate base station.

[0144] This means that if the user equipment moves to the predicted position in the case of switching, it cannot establish a connection with the candidate base station. If the user equipment does not switch, it can still connect to the source base station when it moves to the predicted position. Therefore, try not to switch to the candidate base station, that is, situation 4, which does not meet the position switching conditions.

[0145] Case 5: Reference Figure 10 , the current location of the user equipment is within the coverage of the source base station, the predicted location of the user equipment is not within the coverage of the source base station, the current location of the user equipment is within the coverage of the candidate base station, and the predicted location of the user equipment is within the coverage of the candidate base station.

[0146] This indicates that the current location and predicted location of the user device are both within the coverage of the candidate base station. If the user device does not switch, it will not be able to establish a connection with the source base station when it moves to the predicted location. If the user device switches, the quality of the signal received from the candidate base station is better when it moves to the predicted location. Therefore, it can switch to the candidate base station. That is, situation 5 meets the location switching conditions.

[0147] Case 6: Reference Figure 10 , the current location of the user equipment is within the coverage of the source base station, the predicted location of the user equipment is not within the coverage of the source base station, the current location of the user equipment is within the coverage of the candidate base station, and the predicted location of the user equipment is not within the coverage of the candidate base station.

[0148] This indicates that the candidate base station is closer to the current location but farther from the predicted location. If the user device switches to the candidate base station and reaches the predicted location, it will be unable to establish a connection with the candidate base station. If the user device does not switch to the candidate base station, it will also be unable to establish a connection with the source base station when it reaches the predicted location. Therefore, situation 6 does not meet the location switching conditions.

[0149] Of course, in actual applications, the candidate base station does not meet the location switching condition, and there may be other candidate base stations that meet the location switching condition and the signal switching condition, so that the user equipment is switched to the other candidate base stations.

[0150] Case 7: Reference Figure 11 , the current location of the user equipment is within the coverage of the source base station, the predicted location of the user equipment is not within the coverage of the source base station, the current location of the user equipment is not within the coverage of the candidate base station, and the predicted location of the user equipment is within the coverage of the candidate base station.

[0151] After the user equipment moves to the predicted position, if it continues to connect to the source base station, it cannot establish a connection with the source base station. If it connects to the candidate base station, the signal quality is better. Therefore, situation 7 meets the position switching condition.

[0152] Case 8: Reference Figure 11 , the current location of the user equipment is within the coverage of the source base station, the predicted location of the user equipment is not within the coverage of the source base station, the current location of the user equipment is not within the coverage of the candidate base station, and the predicted location of the user equipment is not within the coverage of the candidate base station.

[0153] After the user equipment moves to the predicted position, if it continues to connect to the source base station, it cannot establish a connection with the source base station. If it connects to the candidate base station, it cannot connect to the candidate base station either. Therefore, situation 8 does not meet the position switching condition.

[0154] In addition, if no candidate base station meets the position switching condition and the signal switching condition, the handover to the candidate base station is not performed, that is, the connection with the source base station is continued.

[0155] When the current and predicted locations are determined, the distances between the current and predicted locations and the source base station are also known. As can be understood from Cases 1 to 4 above, even if the user equipment moves to the predicted location, it remains within the coverage of the source base station and can therefore remain connected to the source base station even without handover.

[0156] However, in areas where base stations are sparsely or unevenly distributed, situations 5 to 8 above may occur, and no candidate base station meets the location switching conditions and signal switching conditions. That is, if the user equipment does not switch to any candidate base station, it will not be able to establish a connection with the source base station when it moves to the predicted location. Therefore, additional conditions can be added to situations 5 to 8 above: That is, if no candidate base station meets the position switching condition and the signal switching condition, that is, no switching is performed to any candidate base station, and it belongs to case 5 to case 8, the distance between the predicted position and the current position can be shortened.

[0157] As mentioned above, the predicted position is related to the sampling period, that is, the predicted position is the position of the user device on the motion route in the next sampling period. Therefore, in actual applications, one sampling period can be shortened so that the distance of the next predicted position relative to the current position is shorter. Of course, after shortening the sampling period, if the number of groups of motion parameters obtained in the shortened sampling period is small, the motion parameters of the previous sampling period can be continued to be obtained, and the motion trajectory can be predicted by multiple groups of sampling parameters. In actual applications, there is no limitation on whether to use multiple groups of motion parameters in one sampling period or motion parameters in multiple sampling periods to predict the motion trajectory of the user device.

[0158] Then, based on the re-determined closer predicted position, it is re-evaluated whether there are candidate base stations that meet the position switching conditions. Even if there is still no candidate base station that meets the position switching conditions, the user equipment moves to the re-determined predicted position and is likely to become one of situations 1 to 4, and can also maintain connection with the source base station.

[0159] Of course, when the user equipment moves to the re-determined predicted position, the re-determined predicted position becomes the current position. Accordingly, the candidate base stations need to be re-determined. Among the re-determined candidate base stations, there may be base stations that meet both the position switching conditions and the signal switching conditions.

[0160] By adding additional conditions in this way, it can be more suitable for areas where base stations are sparsely distributed or unevenly distributed.

[0161] It should be noted that the additional conditions in the above-mentioned situations are only for example. In actual applications, other additional conditions may be added according to various distances, and the embodiments of the present application do not limit this.

[0162] In addition, as another embodiment of the present application, in order to minimize the frequency of user equipment switching base stations, it can also be set that when the source base station can still be effectively used by the user equipment, no switching is performed. For example, when d2 between the predicted position of the user equipment and the source base station is less than S1 (cases 1 to 4), when the user equipment moves to the predicted position, the quality of the signal from the source base station received is likely to be still good, and it can be set to not meet the position switching condition, that is, cases 1 to 4 in the above embodiments can also be set to not meet the position switching condition. Of course, this embodiment is suitable for areas with dense base stations. Even if there is no switching at present, as the user equipment moves and subsequently becomes cases 5 to 8, there will be candidate base stations that meet both the position switching condition and the signal switching condition.

[0163] Of course, it is also possible to determine whether the candidate base station meets the location switching condition by only referring to whether d4 (the distance between the predicted location and the candidate base station) is within the coverage radius of the candidate base station. The location switching conditions are Case 1, Case 3, Case 5, and Case 7 in the above example.

[0164] The embodiments of the present application do not limit the specific content of the location switching conditions. In practical applications, the location switching conditions related to the user's predicted location and the location of the candidate base station are all within the protection scope of the embodiments of the present application.

[0165] As mentioned above, it is necessary to first determine whether there are candidate base stations that meet the position switching conditions. If there are candidate base stations that meet the position switching conditions, the signals of these candidate base stations that meet the position switching conditions are monitored to obtain measurement parameters. Among these base stations, there may not be base stations that meet the signal switching conditions. However, as the user equipment moves along the movement route, before moving to the predicted position, some candidate base stations that meet the position switching conditions may change from not meeting the signal switching conditions to meeting the signal switching conditions.

[0166] Reference Figure 12 As shown in the figure, the sampling step of the inertial navigation system is usually smaller than the monitoring period of the signal. A sampling period T includes multiple sampling steps. Although the figure shows 4 sampling steps, in actual applications, a sampling period T may include more sampling steps. Accordingly, a sampling period may also include 2 or more signal measurement periods.

[0167] That is, after the user equipment determines that there are candidate base stations that meet the location switching conditions, it monitors the signal measurement parameters for the first time. If no candidate base station meets the signal switching conditions, it will continue to monitor the signal measurement parameters of the candidate base stations that meet the location switching conditions according to the monitoring period. It may be that after monitoring the signal measurement parameters of the candidate base stations for the second time, it is determined that there are candidate base stations that meet the signal switching conditions. Therefore, in actual applications, the user equipment can monitor the signal measurement parameters of the candidate base stations that meet the location switching conditions according to the monitoring period after determining that there are candidate base stations that meet the location switching conditions. If, before the next period T arrives, there is a candidate base station that meets the signal switching condition among the candidate base stations that meet the position switching condition, the base station is switched to the candidate base station that meets both the position switching condition and the signal switching condition.

[0168] If, after the next cycle T arrives, none of the candidate base stations that meet the position switching conditions meets the signal switching conditions, the switching is not performed and the cycle of the next sampling cycle T is entered.

[0169] Reference Figure 13, taking into account both the location switching condition and the signal switching condition, a timing diagram of the cell switching method provided in an embodiment of the present application.

[0170] A1: User equipment sends user data 1 to the source node currently providing cell service.

[0171] A2: After receiving user data 1 sent by the user equipment, the source node sends user data 1 to the core network UPF.

[0172] In the embodiment of the present application, when the user equipment sends user data 1 to the source node currently providing cell service for the first time, the user data 1 may carry a movement route, which includes a starting point, an end point, route details, and the like.

[0173] Of course, when the user device determines that the movement route has changed, the changed movement route is first sent to the source node along with the user data. After the changed movement route has been sent to the source node, the subsequent user data sent to the source node may not carry the movement route.

[0174] A3, after receiving user data 1, the core network determines the nodes along the route (i.e., candidate nodes) based on the carried movement route.

[0175] The core network determines the nodes along the movement route by referring to Figure 5 and Figure 6 As shown in the figure, it should be noted that candidate nodes 1 and i in the figure are part of the candidate nodes determined by the user equipment at its current location. Therefore, the candidate nodes determined by the core network include not only candidate nodes 1 and i, but also candidate node j (which is greater than i). Candidate node j is a node that is farther away from the current location or a node that has already been passed.

[0176] A4: The core network sends CHO configuration preparation to all nodes along the line.

[0177] B1. The user equipment sends signal measurement data to the source node.

[0178] B2: After receiving the signal measurement data, the source node determines that the user equipment uses CHO according to the signal measurement data, and determines candidate nodes within point S according to the current location.

[0179] The source node also has pre-recorded information about the user device's movement path. Therefore, it can determine the distance between the user device and the current location of the user device and the S value (which can be a pre-set fixed value or the distance between the user device's most recently predicted location and the current location). For example, the source node configures the user device to report its most recently predicted distance. Each time the user device obtains a predicted location, it calculates the distance and sends it to the source node.

[0180] B3: When the source node determines that the user equipment uses CHO, it sends a CHO request to each candidate node at the current location determined according to the S value.

[0181] B4: The source node receives the CHO responses sent by each candidate node.

[0182] B5. After receiving the CHO responses sent by each candidate node, the source node sends a CHO reset message to the user equipment, carrying the configuration information, signal switching conditions, and location switching conditions of each candidate node.

[0183] B6. After receiving the CHO reset information, the user equipment stores the configuration information of each candidate node and sets the CHO switching condition to the received signal switching condition and location switching condition.

[0184] B7. After storing the configuration information of each candidate node and setting the CHO switching condition to the received signal switching condition and location switching condition, the user equipment sends a reset information to the source node.

[0185] E1: The user equipment evaluates that candidate node 1 and candidate node 2 meet the location switching condition (meet any of the location switching conditions).

[0186] Of course, the location switching condition may also be that the distance between the predicted location of the user equipment and the candidate node is less than the coverage radius of the candidate node.

[0187] B8. In the case that there are candidate nodes that meet the location switching condition, the user equipment evaluates whether there is a candidate node that meets the signal switching condition among the candidate nodes that meet the location switching condition.

[0188] Of course, when the signal switching condition also includes multiple situations, satisfying any one of the signal switching conditions means that the signal switching condition is satisfied.

[0189] B9 , when the candidate node 1 meets the signal switching condition, the user equipment switches to the candidate node 1 according to the configuration information of the candidate node 1 .

[0190] B10, after the user equipment is successfully switched to the candidate node 1, the candidate node 1 sends a switching success message to the source node.

[0191] B11, after receiving the handover success message sent by candidate node 1, the source node sends a handover cancellation message to other candidate nodes i.

[0192] Similarly, in the process of the user equipment switching the serving cell, if early user data forwarding is applied, then after the handover is successful, the source node needs to forward the stored user data 1 to the candidate node 1.

[0193] C1, after receiving the handover success message sent by candidate node 1, the source node sends user data 1 to candidate node 1.

[0194] After the user equipment successfully switches the serving cell, subsequent user data 2 is sent to the switched candidate node 1 and then sent to the core network through the candidate node 1.

[0195] D1: After successfully switching to candidate node 1, the user equipment sends user data 2 to candidate node 1.

[0196] D2, the candidate node serves as the serving cell of the user equipment, and after receiving the user data 2, sends the user data 2 to the core network.

[0197] Of course, each time the user equipment switches to a new node, the user data first sent to the new node carries the movement route. If the movement route remains unchanged, the user data subsequently sent by the user equipment to the currently connected node may no longer carry the movement route.

[0198] After successfully switching to a new node, the new node, as the source node, needs to continue to determine whether the user equipment uses CHO according to the cell switching method provided in the embodiment of the present application. If CHO is continued to be used, the CHO switching condition needs to be further configured for the user equipment. The user equipment automatically determines when the CHO switching condition is met, and when the CHO switching condition is met, switches to a candidate node that meets the CHO switching condition.

[0199] The cell switching method provided in the embodiment of the present application adopts position switching conditions and signal switching conditions, thereby avoiding the situation where a source node with a farther location is re-determined as a target node, thereby reducing the phenomenon of ping-pong switching; at the same time, the position switching conditions are used to limit the nodes that may fail to switch, thereby increasing the probability of successful switching.

[0200] The cell switching method provided in the embodiment of the present application includes: The user equipment receives reset information sent by the first base station (i.e., the source base station in the above embodiment), where the reset information includes information of the second base station (i.e., the candidate base station in the above embodiment) and a CHO execution condition, where the first base station is the base station currently providing cell service for the user equipment, the second base station is a candidate base station for the user equipment at its current location, and the CHO execution condition includes a location switching condition and a signal switching condition; Acquiring, by the user equipment, a first distance between the predicted position of the user equipment and the second base station; Acquiring, by the user equipment, a quality parameter of a signal of the second base station received by the user equipment; The user equipment determines that there is a fourth base station among the second base stations, the first distance of which satisfies the position switching condition and the quality parameter of which satisfies the signal switching condition; The user equipment is handed over to the fourth base station.

[0201] As another embodiment of the present application, before the user equipment obtains the quality parameter of the signal received from the second base station, the method further includes: The user equipment determines that there is a third base station among the second base stations, the third base station having the first distance meeting the location switching condition; Correspondingly, the user equipment acquiring the quality parameter of the signal received from the second base station includes: Acquiring, by the user equipment, a quality parameter of a signal of the third base station received by the user equipment; The user equipment determines that there is a fourth base station among the second base stations, the first distance of which satisfies the position switching condition and the quality parameter of which satisfies the signal switching condition, including: The user equipment determines that there is a fourth base station among the third base stations, whose quality parameter meets the signal switching condition.

[0202] As another embodiment of the present application, the second base station is a base station whose vertical distance to the first road section is within a second distance, and the first road section is the road section on the movement route of the user equipment from the current position of the user equipment to a third distance ahead (for example, S in the above embodiment).

[0203] As another embodiment of the present application, before the user equipment receives the reset information sent by the first base station, the method further includes: The user equipment sends the movement route of the user equipment to the first base station, and the movement route is used to instruct the core network to determine the base stations along the movement route. The movement route is also used to instruct the first base station to determine the candidate base stations of the user equipment at its current location from the base stations along the route.

[0204] As another embodiment of the present application, before the user equipment obtains the first distance between the predicted position of the user equipment and the second base station, the method further includes: The user equipment obtains, by an inertial navigation system carried by the user equipment, motion parameters of the user equipment according to a sampling period; The user equipment obtains a predicted position of the user equipment in a next sampling period according to the motion parameter and the current position of the user equipment.

[0205] As another embodiment of the present application, the user equipment obtaining the motion parameters of the user equipment according to a sampling period through an inertial navigation system carried by the user equipment includes: The user equipment obtains, by means of an inertial navigation system carried by the user equipment, multiple sets of motion parameters of the user equipment according to a sampling step within a sampling period; Accordingly, the user equipment obtains a predicted position of the user equipment in the next sampling period according to the motion parameter and the current position of the user equipment, including: The user equipment obtains a predicted motion trajectory of the user equipment based on multiple sets of motion parameters of the user equipment acquired according to a sampling step within a sampling period, where the predicted motion trajectory includes a predicted position of the user equipment in a next sampling period.

[0206] As another embodiment of the present application, the inertial navigation system includes: an accelerometer and a gyroscope; the motion parameters of the user equipment include: a motion speed and a motion acceleration of the user equipment; The user equipment obtains, according to the motion parameter and the current position of the user equipment, a predicted position of the user equipment in a next sampling period, including: The user equipment obtains a predicted travel distance of the user equipment until a next sampling period according to the movement speed, movement acceleration and sampling period of the user equipment; The user equipment obtains a predicted position of the user equipment in a next sampling period according to the movement route of the user equipment and the predicted travel distance.

[0207] As another embodiment of the present application, the user equipment determining that there is a third base station in the second base station whose first distance satisfies the location switching condition includes: The user equipment determines that there is a third base station among the second base stations, the first distance of which is smaller than the coverage radius of the second base station.

[0208] As another embodiment of the present application, the user equipment determining that there is a fourth base station among the third base stations whose quality parameter meets the signal switching condition includes: Determining, by the user equipment, that there is a fourth base station among the third base stations, the fourth base station having a higher signal quality than the first base station; Or, the user equipment determines that there is a fourth base station among the third base stations, the signal quality of which is higher than the first value; Alternatively, the user equipment determines that among the third base stations, there is a fourth base station whose signal quality is higher than the first value and whose signal quality is higher than the first base station.

[0209] As another embodiment of the present application, handing over, by the user equipment, to the fourth base station includes: The user equipment determines a base station with the highest signal quality among the fourth base stations as a target base station; Alternatively, the user equipment determines a base station among the fourth base stations that has the smallest first distance to the predicted location of the user equipment as the target base station; Alternatively, the user equipment determines one of the fourth base stations as the target base station based on a signal quality of each base station in the fourth base stations and a first distance between the base station and the predicted location of the user equipment; The user equipment is handed over to the target base station.

[0210] As another embodiment of the present application, the quality parameter includes: at least one of: reference signal received power, reference signal received quality and signal to interference plus noise ratio; the signal quality is a weighted sum of the quality parameters.

[0211] As another embodiment of the present application, the method further includes: Before starting to move along the movement route, or within a first period of time after starting to move along the movement route, the user equipment sends the movement route to a base station currently providing cell service for the user equipment.

[0212] As another embodiment of the present application, after the user equipment is switched to the fourth base station, the method further includes: The user equipment forwards the movement route to the fourth base station through the first base station; Alternatively, the user equipment sends the movement route to the fourth base station.

[0213] As another embodiment of the present application, the user equipment obtaining the quality parameter of the signal of the third base station received by the user equipment includes: The user equipment monitors, within a current sampling period, a quality parameter of a signal of the third base station according to a monitoring period, where the current sampling period is a sampling period corresponding to the predicted position; Correspondingly, the user equipment determining that there is a fourth base station among the third base stations whose quality parameter satisfies the signal switching condition includes: Before the current sampling period ends, the user equipment determines that there is a fourth base station among the third base stations whose quality parameter meets the signal switching condition.

[0214] It should be understood that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0215] An embodiment of the present application further provides a computer-readable storage medium, which stores a computer program. When the computer program is run on an electronic device, it can implement the steps in the above-mentioned various method embodiments.

[0216] The embodiments of the present application further provide a computer program product. When the computer program product is run on an electronic device or a wireless router, the electronic device can implement the steps in the above-mentioned various method embodiments.

[0217] If the integrated unit is implemented as a software functional unit and sold or used as a standalone product, it can be stored in a computer-readable storage medium. Based on this understanding, all or part of the process steps in the above-mentioned method embodiments can be implemented by a computer program instructing the relevant hardware. The computer program can be stored in a computer-readable storage medium. When executed by a processor, the computer program can implement the steps of each of the above-mentioned method embodiments. The computer program includes computer program code, which can be in source code form, object code form, executable file, or some intermediate form. A computer-readable medium can include at least: any entity or device capable of carrying the computer program code to the first device, a recording medium, computer memory, read-only memory (ROM), random access memory (RAM), an electrical carrier signal, a telecommunications signal, and a software distribution medium. Examples include a USB flash drive, a removable hard drive, a magnetic disk, or an optical disk. In some jurisdictions, based on legislation and patent practice, computer-readable media cannot be electrical carrier signals or telecommunications signals.

[0218] The present application also provides a chip comprising a processor coupled to a memory, wherein the processor invokes a computer program stored in the memory to implement the steps of any method embodiment of the present application. The chip may be a single chip or a chip module composed of multiple chips.

[0219] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant description of other embodiments.

[0220] Those skilled in the art will appreciate that the units and method steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0221] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present application, and should all be included in the scope of protection of the present application.

Claims

1. A cell handover method, characterized in that: include: The user equipment receives reset information sent by the first base station, where the reset information includes information of the second base station and a CHO execution condition, where the first base station is a base station currently providing cell services for the user equipment, the second base station is a candidate base station for the user equipment at a current location, and the CHO execution condition includes a location switching condition and a signal switching condition; Acquiring, by the user equipment, a first distance between the predicted position of the user equipment and the second base station; Acquiring, by the user equipment, a quality parameter of a signal of the second base station received by the user equipment; The user equipment determines that there is a fourth base station among the second base stations, the first distance of which satisfies the position switching condition and the quality parameter of which satisfies the signal switching condition; The user equipment is handed over to the fourth base station.

2. The method according to claim 1, wherein Before the user equipment obtains the quality parameter of the signal received from the second base station, the method further includes: The user equipment determines that there is a third base station among the second base stations, the third base station having the first distance meeting the location switching condition; Correspondingly, the user equipment acquiring the quality parameter of the signal received from the second base station includes: Acquiring, by the user equipment, a quality parameter of a signal of the third base station received by the user equipment; The user equipment determines that there is a fourth base station among the second base stations, the first distance of which satisfies the position switching condition and the quality parameter of which satisfies the signal switching condition, including: The user equipment determines that there is a fourth base station among the third base stations, whose quality parameter meets the signal switching condition.

3. The method according to claim 1, wherein The second base station is a base station whose vertical distance to the first road section is within a second distance, and the first road section is a road section from the current position of the user equipment to a third distance ahead on the movement route of the user equipment.

4. The method according to claim 1, wherein Before the user equipment receives the reset information sent by the first base station, the method further includes: The user equipment sends the movement route of the user equipment to the first base station, and the movement route is used to instruct the core network to determine the base stations along the movement route. The movement route is also used to instruct the first base station to determine the candidate base stations of the user equipment at its current location from the base stations along the route.

5. The method according to claim 2, wherein Before the user equipment obtains the first distance between the predicted position of the user equipment and the second base station, the method further includes: The user equipment obtains, by an inertial navigation system carried by the user equipment, motion parameters of the user equipment according to a sampling period; The user equipment obtains a predicted position of the user equipment in a next sampling period according to the motion parameter and the current position of the user equipment.

6. The method according to claim 5, wherein The user equipment acquiring the motion parameters of the user equipment according to a sampling period through an inertial navigation system carried by the user equipment includes: The user equipment obtains, by means of an inertial navigation system carried by the user equipment, multiple sets of motion parameters of the user equipment according to a sampling step within a sampling period; Accordingly, the user equipment obtains a predicted position of the user equipment in the next sampling period according to the motion parameter and the current position of the user equipment, including: The user equipment obtains a predicted motion trajectory of the user equipment based on multiple sets of motion parameters of the user equipment acquired according to a sampling step within a sampling period, where the predicted motion trajectory includes a predicted position of the user equipment in a next sampling period.

7. The method according to claim 5, wherein The inertial navigation system includes: an accelerometer and a gyroscope; the motion parameters of the user equipment include: the motion speed and motion acceleration of the user equipment; The user equipment obtains, according to the motion parameter and the current position of the user equipment, a predicted position of the user equipment in a next sampling period, including: The user equipment obtains a predicted travel distance of the user equipment until a next sampling period according to the movement speed, movement acceleration and sampling period of the user equipment; The user equipment obtains a predicted position of the user equipment in a next sampling period according to the movement route of the user equipment and the predicted travel distance.

8. The method according to any one of claims 1 to 7, wherein: The user equipment determining that there is a third base station in the second base station whose first distance satisfies the location switching condition includes: The user equipment determines that there is a third base station among the second base stations, the first distance of which is smaller than the coverage radius of the second base station.

9. The method according to claim 7, wherein The user equipment determining that there is a fourth base station among the third base stations whose quality parameter satisfies the signal switching condition includes: Determining, by the user equipment, that there is a fourth base station among the third base stations, the fourth base station having a higher signal quality than the first base station; Or, the user equipment determines that there is a fourth base station among the third base stations, the signal quality of which is higher than the first value; Alternatively, the user equipment determines that among the third base stations, there is a fourth base station whose signal quality is higher than the first value and whose signal quality is higher than the first base station.

10. The method according to claim 9, wherein Handing over the user equipment to the fourth base station includes: The user equipment determines a base station with the highest signal quality among the fourth base stations as a target base station; Alternatively, the user equipment determines a base station among the fourth base stations that has the smallest first distance to the predicted location of the user equipment as the target base station; Alternatively, the user equipment determines one of the fourth base stations as the target base station based on a signal quality of each base station in the fourth base stations and a first distance between the base station and the predicted location of the user equipment; The user equipment is handed over to the target base station.

11. The method according to claim 10, wherein The quality parameters include: at least one of reference signal received power, reference signal received quality, and signal to interference plus noise ratio; the signal quality is a weighted sum of the quality parameters.

12. The method according to claim 3, wherein The method further comprises: Before starting to move along the movement route, or within a first period of time after starting to move along the movement route, the user equipment sends the movement route to a base station currently providing cell service for the user equipment.

13. The method according to claim 12, wherein: After the user equipment is switched to the fourth base station, the method further includes: The user equipment forwards the movement route to the fourth base station through the first base station; Alternatively, the user equipment sends the movement route to the fourth base station.

14. The method according to claim 6, wherein The user equipment acquiring the quality parameter of the signal of the third base station received by the user equipment includes: The user equipment monitors, within a current sampling period, a quality parameter of a signal of the third base station according to a monitoring period, where the current sampling period is a sampling period corresponding to the predicted position; Correspondingly, the user equipment determining that there is a fourth base station among the third base stations whose quality parameter satisfies the signal switching condition includes: Before the current sampling period ends, the user equipment determines that there is a fourth base station among the third base stations whose quality parameter meets the signal switching condition.

15. An electronic device, characterized in that: The electronic device comprises one or more processors and one or more memories; wherein the one or more memories are coupled to the one or more processors, and the one or more memories are used to store a computer program, and when the one or more processors execute the computer program, the electronic device executes the method according to any one of claims 1 to 14.

16. A chip system, applied to electronic equipment, comprising one or more processors, characterized in that: The processor is configured to call computer instructions so that the electronic device executes the method according to any one of claims 1 to 14.

17. A computer-readable storage medium comprising a computer program, characterized in that When the computer program is run on an electronic device, the electronic device is enabled to perform the method according to any one of claims 1 to 14.

18. A computer program product, characterized in that When the computer program product is run on an electronic device, the electronic device is enabled to perform the method according to any one of claims 1 to 14.

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