A cell measurement method, device, unmanned aerial vehicle and core network equipment

Abstract

The application provides a cell measurement method and device, a UAV and a core network device, and relates to the technical field of communication. The method comprises the following steps: obtaining a target cell switching list corresponding to a flight path of a UAV; determining an opening priority of multiple directional antennas on the UAV according to the target cell switching list; different directional antennas are used for beam scanning in different directions; opening the directional antennas to perform cell measurement according to the opening priority, and sending the measurement results obtained by measurement to a base station; the target cell switching list comprises a target switching band range corresponding to the flight path, cell information and a priority of a target switchable cell corresponding to the target switching band range. The scheme of the application solves the problem that the UAV cannot perform service communication in the current UAV measurement gap, and the reliability of cell switching based on the measurement results is low.

Description

Technical Field

[0001] This invention relates to the field of communication technology, and in particular to a cell measurement method, device, unmanned aerial vehicle (UAV), and core network equipment. Background Technology

[0002] Because there is no dominant cell coverage in the air, drones will receive a large number of neighboring cell signals, which will cause the signal-to-interference-plus-noise ratio (SINR) to deteriorate severely and the air handover to be frequent. This will result in large fluctuations in uplink service rates, frequent disconnections, and an inability to stably support high-quality video backhaul services, and may even lead to accidents.

[0003] Currently, most UAV handover schemes using directional antennas to reduce interference employ beam scanning to align with the cell to be measured. For UAVs with a defined path, the reference signal receiving power (RSRP) value is calculated based on the path information to obtain a suitable target handover cell for handover preparation. However, schemes using directional antenna beam scanning for measurement have the drawback of being unable to conduct service communication during the UAV measurement intervals; while cell handover schemes that obtain the target handover cell by pre-calculating the RSRP values ​​of each cell suffer from unreliability due to relying solely on calculated information. Summary of the Invention

[0004] The purpose of this invention is to provide a cell measurement method, apparatus, UAV, and core network equipment to solve the problems that current UAVs cannot conduct service communication during measurement intervals and that cell handover based on measurement results has low reliability.

[0005] To achieve the above objectives, embodiments of the present invention provide a cell measurement method applied to an unmanned aerial vehicle (UAV), comprising:

[0006] Obtain the target cell switching list corresponding to the drone's flight path;

[0007] Based on the target cell handover list, the activation priority of multiple directional antennas on the UAV is determined; wherein, different directional antennas are used for beam scanning in different directions;

[0008] According to the activation priority, the directional antenna is activated to perform cell measurements, and the measurement results are sent to the base station.

[0009] The target cell handover list includes: the target handover zone range corresponding to the flight path, and the cell information and priority of the target handoverable cells corresponding to the target handover zone range.

[0010] Optionally, obtaining the target cell handover list corresponding to the UAV's flight path includes:

[0011] The flight path is sent to the core network equipment;

[0012] Receive the target cell handover list sent by the core network equipment according to the flight path.

[0013] Optionally, obtaining the target cell handover list corresponding to the UAV's flight path includes:

[0014] The flight path is sent to the core network equipment;

[0015] The system receives a first cell handover list sent by the core network device according to the flight path; wherein the first cell handover list includes: a first handover band range corresponding to the flight path, cell information and priority of a first handoverable cell corresponding to the first handover band range;

[0016] If the current location of the drone is within the first handover zone, then the first cell handover list is determined to be the target cell handover list;

[0017] If the current location of the UAV is not within the first handover zone, the first information is sent to the core network device, and the target cell list sent by the core network device based on the first information is received; wherein, the first information includes: the current location of the UAV and related information of cell measurement.

[0018] Optionally, obtaining the target cell handover list corresponding to the UAV's flight path includes:

[0019] Receive measurement configuration information sent by the base station; wherein, the measurement configuration information includes relevant information about cell measurement;

[0020] Based on the relevant information measured in the cell, the current location of the UAV, and the flight path, the target cell handover list is determined.

[0021] Optionally, obtaining the target cell handover list corresponding to the UAV's flight path includes:

[0022] The flight path of the UAV is sent to the core network equipment, and measurement configuration information is received from the base station; wherein, the measurement configuration information includes relevant information on cell measurement;

[0023] The system receives a second cell handover list sent by the core network device according to the flight path; wherein the second cell handover list includes: a second handover band range corresponding to the flight path, cell information and priority of a second handoverable cell corresponding to the second handover band range;

[0024] If the current location of the drone is within the second handover zone, then the second cell handover list is determined to be the target cell handover list;

[0025] If the current location of the UAV is not within the second handover zone, the target cell handover list is determined based on the relevant information measured by the cell, the current location of the UAV, and the flight path.

[0026] Optionally, the method further includes:

[0027] The target cell list is sent to the core network equipment.

[0028] Optionally, determining the target cell handover list based on the relevant information measured by the cell, the current location of the UAV, and the flight path includes:

[0029] Based on the relevant information measured in the cell, determine the location of the base station corresponding to the cell to be handed over;

[0030] The priority of the cell to be handed over is determined based on the current location of the drone, the location of the base station, and relevant information measured by the cell.

[0031] The target cell handover list is determined based on the current location of the UAV, the relevant information measured by the cell, and the priority of the cell to be handed over.

[0032] Optionally, determining the priority of the cell to be handed over based on the current location of the drone, the location of the base station, and relevant information from cell measurements includes:

[0033] Based on the current location of the UAV, the location of the base station, and the relevant information measured by the cell, the reference signal received power (RSRP) corresponding to the cell to be handed over is determined;

[0034] Based on the flight path, determine the maximum flight distance that the cell to be switched can provide for the UAV;

[0035] The priority of the cell to be handed over is determined based on the RSRP and the longest flight distance.

[0036] Optionally, determining the Reference Received Power (RSRP) corresponding to the cell to be handed over based on the current location of the UAV, the location of the base station, and relevant information from the cell measurement includes:

[0037] Based on the relevant information measured in the cell, determine the antenna pattern and transmit power of the cell to be switched over;

[0038] The antenna gain is determined based on the current location of the UAV, the location of the base station, and the antenna pattern.

[0039] The path loss of the UAV is determined based on the free space loss model;

[0040] The RSRP corresponding to the cell to be handed over is determined based on the transmit power, the antenna gain, and the path loss.

[0041] Optionally, determining the priority of the cell to be handed over based on the RSRP and the longest flight distance includes:

[0042] Using the formula: Q=ω1RSRP+ω2D longest Determine the cell handover priority factor of the cell to be handed over;

[0043] The priority of the cell to be handed over is determined based on the cell handover priority factor.

[0044] Where Q is the cell handover priority factor of the cell to be handed over, RSRP is the reference signal received power value of the cell to be handed over, and D longest The longest flight distance value of the UAV is provided for the cell to be switched, where ω1 and ω2 are weight values.

[0045] Optionally, according to the activation priority, the directional antenna is activated to perform cell measurements, and the measurement results are sent to the base station.

[0046] The directional antennas are activated sequentially in descending order of activation priority to perform cell measurements, and the measurement results are sent to the base station when the measured results meet the event conditions.

[0047] Optionally, after sending the measured results to the base station, the method further includes:

[0048] Receive the handover command sent by the base station;

[0049] According to the handover command, switch from the source serving cell to the target serving cell;

[0050] The target cell handover list is updated based on the source serving cell priority information and the target serving cell identifier; or, the source serving cell priority information and the target serving cell identifier are sent to the core network equipment.

[0051] To achieve the above objectives, embodiments of the present invention provide a cell measurement method applied to core network equipment, comprising:

[0052] Receive the flight path of the drone sent by the drone;

[0053] Based on the flight path, determine the target cell handover list corresponding to the UAV;

[0054] Send the target cell handover list to the drone;

[0055] The target cell handover list includes: the target handover zone range corresponding to the flight path, and the cell information and priority of the target handoverable cells corresponding to the target handover zone range.

[0056] Optionally, determining the target cell handover list corresponding to the UAV based on the flight path includes:

[0057] From the database, determine the target cell handover list corresponding to the flight path.

[0058] Optionally, determining the target cell handover list corresponding to the UAV based on the flight path includes:

[0059] Receive first information sent by the drone; wherein the first information includes: the current location of the drone and relevant information of cell measurement;

[0060] Based on the first information, determine the target cell handover list;

[0061] The list of target cells is sent to the drone.

[0062] Optionally, before receiving the first information sent by the drone, the method further includes:

[0063] From the database, determine the first cell handover list corresponding to the flight path; wherein, the first cell handover list includes: the first handover zone range corresponding to the flight path, and the cell information and priority of the first handoverable cell corresponding to the first handover zone range;

[0064] Send the first cell handover list to the drone;

[0065] Determining the target cell handover list based on the first information includes:

[0066] Based on the first information, the first cell handover list is updated to obtain the target cell handover list.

[0067] Optionally, determining the target cell handover list based on the first information includes:

[0068] Based on the relevant information measured in the cell, determine the location of the base station corresponding to the cell to be handed over;

[0069] The priority of the cell to be handed over is determined based on the current location of the drone, the location of the base station, and relevant information measured by the cell.

[0070] The target cell handover list is determined based on the current location of the UAV, the relevant information measured by the cell, and the priority of the cell to be handed over.

[0071] Optionally, determining the priority of the cell to be handed over based on the current location of the drone, the location of the base station, and relevant information from cell measurements includes:

[0072] Based on the current location of the UAV, the location of the base station, and the relevant information measured by the cell, the reference signal received power (RSRP) corresponding to the cell to be handed over is determined;

[0073] Based on the flight path, determine the maximum flight distance that the cell to be switched can provide for the UAV;

[0074] The priority of the cell to be handed over is determined based on the RSRP and the longest flight distance.

[0075] Optionally, determining the Reference Received Power (RSRP) of the cell to be handed over based on the current location of the UAV, the location of the base station, and relevant information from cell measurements includes:

[0076] Based on the relevant information measured in the cell, determine the antenna pattern and transmit power of the cell to be switched over;

[0077] The antenna gain is determined based on the current location of the UAV, the location of the base station, and the antenna pattern.

[0078] The path loss of the UAV is determined based on the free space loss model;

[0079] The RSRP corresponding to the cell to be handed over is determined based on the transmit power, the antenna gain, and the path loss.

[0080] Optionally, determining the priority of the cell to be handed over based on the RSRP and the longest flight distance includes:

[0081] Using the formula: Q=ω1RSRP+ω2D longest Determine the cell handover priority factor of the cell to be handed over;

[0082] The priority of the cell to be handed over is determined based on the cell handover priority factor.

[0083] Where Q is the cell handover priority factor of the cell to be handed over, RSRP is the reference signal received power value of the cell to be handed over, and D longest The longest flight distance value of the UAV is provided for the cell to be switched, where ω1 and ω2 are weight values.

[0084] Optionally, after sending the target cell handover list to the drone, the method further includes:

[0085] Receive information related to the source serving cell priority of the drone and the cell identifier of the target serving cell sent by the drone;

[0086] The target cell handover list is updated based on the relevant information of the source serving cell priority and the cell identifier of the target serving cell.

[0087] To achieve the above objectives, embodiments of the present invention provide a cell measurement device applied to an unmanned aerial vehicle (UAV), comprising:

[0088] The acquisition module is used to obtain the target cell switching list corresponding to the drone's flight path;

[0089] The determination module is used to determine the activation priority of multiple directional antennas on the UAV based on the target cell handover list; wherein, different directional antennas are used for beam scanning in different directions;

[0090] The first transmitting module is used to activate the directional antenna to perform cell measurement according to the activation priority, and send the measurement results to the base station.

[0091] The target cell handover list includes: the target handover zone range corresponding to the flight path, and the cell information and priority of the target handoverable cells corresponding to the target handover zone range.

[0092] To achieve the above objectives, embodiments of the present invention provide a drone, comprising: a transceiver, a processor, a memory, and a program or instructions stored in the memory and executable on the processor; characterized in that, when the processor executes the program or instructions, it implements the steps in the cell measurement method described above.

[0093] To achieve the above objectives, embodiments of the present invention provide a cell measurement device applied to core network equipment, comprising:

[0094] The first receiving module is used to receive the flight path of the UAV sent by the UAV;

[0095] The determination module is used to determine the target cell switching list corresponding to the UAV based on the flight path;

[0096] The sending module is used to send the target cell handover list to the UAV;

[0097] The target cell handover list includes: the target handover zone range corresponding to the flight path, and the cell information and priority of the target handoverable cells corresponding to the target handover zone range.

[0098] To achieve the above objectives, embodiments of the present invention provide a core network device, including: a transceiver, a processor, a memory, and a program or instructions stored in the memory and executable on the processor; characterized in that, when the processor executes the program or instructions, it implements the steps in the cell measurement method described above.

[0099] To achieve the above objectives, embodiments of the present invention provide a readable storage medium having a program or instructions stored thereon, which, when executed by a processor, implement the steps in the cell measurement method described above.

[0100] The beneficial effects of the above-described technical solution of the present invention are as follows:

[0101] In this embodiment of the invention, the UAV obtains a target cell handover list corresponding to its flight path and determines the activation priority of multiple directional antennas on the UAV based on the target cell handover list. Then, according to the activation priority, the directional antennas are activated to perform cell measurements, and the measurement results are sent to the base station. This allows the location of the serving cell to be determined through real-time updates of the target cell handover list, enabling the original directional antenna to be turned off in time and the appropriate directional antenna to be activated for data transmission and reception, maintaining optimal communication with the serving cell. By selectively activating and deactivating some antenna ports, the transmission and reception interference between the UAV and cells in other directions can be significantly reduced. Furthermore, the UAV can obtain the handover priority ranking of switchable cells from the target cell handover list, and thus determine the activation priority of each directional antenna during cell measurement. By activating only some directional antennas at the same time according to the priority order, the cell measurement time is reduced, significantly reducing transmission and reception interference compared to UAV communication using omnidirectional antennas. Attached Figure Description

[0102] Figure 1 This is a flowchart of a UAV-based cell measurement method according to an embodiment of the present invention;

[0103] Figure 2 This is a schematic diagram of a drone according to an embodiment of the present invention;

[0104] Figure 3This is one of the schematic diagrams illustrating the interaction between the UAV and the core network equipment in an embodiment of the present invention;

[0105] Figure 4 This is the second schematic diagram illustrating the interaction between the UAV and the core network equipment in an embodiment of the present invention;

[0106] Figure 5 This is a block diagram of a UAV-side cell measurement device according to an embodiment of the present invention;

[0107] Figure 6 This is a block diagram of a drone according to an embodiment of the present invention;

[0108] Figure 7 This is a flowchart of a cell measurement method on the core network equipment side according to an embodiment of the present invention;

[0109] Figure 8 This is the third schematic diagram illustrating the interaction between the UAV and the core network equipment in an embodiment of the present invention;

[0110] Figure 9 This is the fourth schematic diagram illustrating the interaction between the UAV and the core network equipment in an embodiment of the present invention.

[0111] Figure 10 This is a block diagram of a cell measurement device on the core network equipment side according to an embodiment of the present invention;

[0112] Figure 11 This is a block diagram of the core network device according to an embodiment of the present invention. Detailed Implementation

[0113] To make the technical problems, technical solutions and advantages of the present invention clearer, a detailed description will be given below in conjunction with the accompanying drawings and specific embodiments.

[0114] It should be understood that the phrase "one embodiment" or "an embodiment" throughout the specification means that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of the invention. Therefore, "in one embodiment" or "in an embodiment" appearing throughout the specification do not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments.

[0115] In various embodiments of the present invention, it should be understood that the sequence number of each process described below does not imply 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 the present invention.

[0116] In addition, the terms "system" and "network" are often used interchangeably in this article.

[0117] In the embodiments provided in this application, it should be understood that "B corresponding to A" means that B is associated with A, and B can be determined based on A. However, it should also be understood that determining B based on A does not mean determining B solely based on A; B can also be determined based on A and / or other information.

[0118] like Figure 1 As shown, an embodiment of the present invention provides a cell measurement method applied to a drone, comprising:

[0119] Step 11: Obtain the target cell switching list corresponding to the drone's flight path.

[0120] Optionally, the drone can obtain the target cell handover list corresponding to its flight path by receiving the target cell handover list sent by the core network equipment; the drone can also determine the target cell handover list corresponding to its flight path based on the measurement configuration parameters sent by the base station, the drone's current location, etc.

[0121] Optionally, the target cell handover list includes: the target handover zone range corresponding to the flight path, and the cell information and priority of the target handoverable cells corresponding to the target handover zone range.

[0122] Optionally, the multiple switchable cells in the target cell handover list corresponding to each handover band range can be arranged in descending order of priority of the switchable cells.

[0123] Optionally, if the UAV is set to fly in a straight line, the flight path is a set of inflection points; the handover zone is the range within which the UAV can perform cell handover; the switchable cells are the cells that can be switched within the handover zone, and the cell information (or target switchable cell ID set) may include: cell identifier, cell location information, and information related to the priority of the switchable cells (such as D in the following embodiment). longest The values ​​(such as Q value) and the frequency f at which the switchable cell is selected as the target cell for handover are shown in Table 1.

[0124] Table 1

[0125]

[0126]

[0127] Step 12: Determine the activation priority of multiple directional antennas on the UAV according to the target cell handover list; wherein, different directional antennas are used for beam scanning in different directions.

[0128] like Figure 2As shown, the drone can be equipped with N directional antennas 21, which are arranged in a 360° configuration. Thus, the N directional antennas 21 arranged in a 360° configuration can form a drone antenna device.

[0129] Step 13: According to the activation priority, activate the directional antenna to perform cell measurement, and send the measurement results to the base station.

[0130] Optionally, when activating directional antennas according to their priority order, the highest priority 1-2 directional antennas can be activated first for cell measurement. If the event conditions are met, the measurement results are reported to the base station. If not, the next priority 1-2 directional antennas are activated for cell measurement, and so on.

[0131] In the above scheme, when the UAV interacts with the serving cell, its own mobility causes the serving cell's location to change. The UAV determines the serving cell's location based on the real-time update of the target cell handover list, and promptly shuts down the original directional antenna and turns on the appropriate directional antenna at that moment for data transmission and reception, thus maintaining optimal communication with the serving cell. By selectively turning on and off some antenna ports, the UAV can significantly reduce transmission and reception interference with cells in other directions. The UAV can obtain the handover priority ranking of switchable cells from the target handover cell list, and then obtain the activation priority of each directional antenna during cell measurement. According to the priority order, only some directional antennas are turned on at the same time, reducing cell measurement time. Compared with UAV communication using omnidirectional antennas, this greatly reduces transmission and reception interference.

[0132] Optionally, obtaining the target cell handover list corresponding to the UAV's flight path includes:

[0133] The flight path is sent to the core network equipment;

[0134] Receive the target cell handover list sent by the core network equipment according to the flight path.

[0135] Among them, core network equipment can be User Plane Function (UPF) entities.

[0136] In this embodiment, before the UAV takes flight, it uploads the flight path m to the core network equipment. The core network equipment can then query the database to see if a cell handover list M corresponding to the flight path m exists. mIf a matching cell handover list exists, the matching cell handover list can be sent to the UAV; if not, the core network equipment can calculate the target cell list based on the flight path, the current location reported by the UAV, and relevant cell measurement information, and then send it to the UAV.

[0137] Optionally, obtaining the target cell handover list corresponding to the UAV's flight path includes:

[0138] The flight path is sent to the core network equipment;

[0139] The system receives a first cell handover list sent by the core network device according to the flight path; wherein the first cell handover list includes: a first handover band range corresponding to the flight path, cell information and priority of a first handoverable cell corresponding to the first handover band range;

[0140] If the current location of the drone is within the first handover zone, then the first cell handover list is determined to be the target cell handover list;

[0141] If the current location of the UAV is not within the first handover zone, the first information is sent to the core network device, and the target cell list sent by the core network device based on the first information is received; wherein, the first information includes: the current location of the UAV and related information of cell measurement.

[0142] In this embodiment, before the UAV takes flight, it uploads the flight path m to the core network equipment. The core network equipment can then query the database to see if a cell handover list M corresponding to the flight path m exists. m If a matching cell handover list exists, it can be sent to the UAV. When the UAV receives the matching cell handover list (i.e., the first cell handover list) from the core network equipment, it determines whether its current location is within the range of the first cell handover list. If it confirms that the target cell handover list has been obtained, it performs the steps of antenna activation, cell measurement, and cell handover according to the target cell handover list. If not, the UAV can send its current location and cell measurement information to the core network equipment, so that the core network equipment can calculate the target cell list based on the flight path and the UAV's reported current location and cell measurement information, and then send it to the UAV.

[0143] Optionally, obtaining the target cell handover list corresponding to the UAV's flight path includes:

[0144] Receive measurement configuration information sent by the base station; wherein, the measurement configuration information includes relevant information about cell measurement;

[0145] Based on the relevant information measured in the cell, the current location of the UAV, and the flight path, the target cell handover list is determined.

[0146] Optionally, the method may further include: sending the flight path of the UAV to the core network equipment, wherein the core network equipment may store a cell handover list M corresponding to each path. m If the UAV does not receive the cell handover list matched with its uploaded flight path from the core network equipment, the target cell handover list is determined based on the relevant information of the cell measurement, the current location of the UAV, and the flight path.

[0147] Furthermore, the method also includes: sending the target cell list to the core network equipment, so that the core network equipment can update the cell handover list corresponding to each path in its database according to the target cell handover list determined by the UAV, such as... Figure 3 As shown.

[0148] Optionally, obtaining the target cell handover list corresponding to the UAV's flight path includes:

[0149] The flight path of the UAV is sent to the core network equipment, and measurement configuration information is received from the base station; wherein, the measurement configuration information includes relevant information on cell measurement;

[0150] The system receives a second cell handover list sent by the core network device according to the flight path; wherein the second cell handover list includes: a second handover band range corresponding to the flight path, cell information and priority of a second handoverable cell corresponding to the second handover band range;

[0151] If the current location of the drone is within the second handover zone, then the second cell handover list is determined to be the target cell handover list;

[0152] If the current location of the UAV is not within the second handover zone, the target cell handover list is determined based on the relevant information measured by the cell, the current location of the UAV, and the flight path.

[0153] Furthermore, the method also includes: sending the target cell list to the core network equipment, so that the core network equipment can update the cell handover list corresponding to each path in its database according to the target cell handover list determined by the UAV, such as... Figure 4 As shown.

[0154] Optionally, determining the target cell handover list based on the relevant information measured by the cell, the current location of the UAV, and the flight path includes:

[0155] Based on the relevant information measured in the cell, determine the location of the base station corresponding to the cell to be handed over;

[0156] The priority of the cell to be handed over is determined based on the current location of the drone, the location of the base station, and relevant information measured by the cell.

[0157] The target cell handover list is determined based on the current location of the UAV, the relevant information measured by the cell, and the priority of the cell to be handed over.

[0158] Optionally, determining the priority of the cell to be handed over based on the current location of the drone, the location of the base station, and relevant information from cell measurements includes:

[0159] Based on the current location of the UAV, the location of the base station, and the relevant information measured by the cell, the reference signal received power (RSRP) corresponding to the cell to be handed over is determined;

[0160] Based on the flight path, determine the maximum flight distance that the cell to be switched can provide for the UAV;

[0161] The priority of the cell to be handed over is determined based on the RSRP and the longest flight distance.

[0162] Optionally, the base station can send measurement configuration parameters to the UAV via Radio Resource Control (RRC) Connection Reconfiguration messages. These measurement configuration parameters can include relevant information about cell measurements, such as the list of cells to be measured, reporting methods, measurement identifiers, event parameters, etc., so that the UAV can perform measurement configuration.

[0163] When the RSRP measured by the UAV is lower than the threshold for enabling same-frequency and different-frequency measurements, it will initiate a measurement of the target object. Before measurement, the UAV needs to determine the cell handover list and determine the activation priority of each directional antenna according to the priority of the switchable cells in the cell handover list.

[0164] For example, the priority of the cell to be handed over can be determined based on the RSRP and the maximum flight distance, wherein the RSRP of each cell can be determined based on the current location of the UAV, the location of the base station and relevant information measured by the cell; the maximum flight distance provided by the cell to be handed over to the UAV can be determined based on the flight path.

[0165] Optionally, determining the Reference Received Power (RSRP) corresponding to the cell to be handed over based on the current location of the UAV, the location of the base station, and relevant information from the cell measurement includes:

[0166] Based on the relevant information measured in the cell, determine the antenna pattern and transmit power of the cell to be switched over;

[0167] The antenna gain is determined based on the current location of the UAV, the location of the base station, and the antenna pattern.

[0168] The path loss of the UAV is determined based on the free space loss model;

[0169] The RSRP corresponding to the cell to be handed over is determined based on the transmit power, the antenna gain, and the path loss.

[0170] Determining the antenna gain based on the current location of the UAV, the location of the base station, and the antenna pattern may include: determining the azimuth angle of the UAV based on the location information of the UAV and the location information of the base station; and determining the antenna gain based on the azimuth angle and the antenna pattern of the cell to be switched in the cell information.

[0171] For example, the RSRP corresponding to the cell to be handed over can be determined using the following formula:

[0172] RSRP = Transmit Power + Antenna Gain θ - Path loss

[0173] Where θ is the azimuth angle, which is the angle between the line connecting the current position of the UAV and the position of the base station and the antenna normal. The path loss is considered using the free space loss model Loss = 20lg(frequency F) + 20lg(distance d) + 32.4, where d is the distance between the position of the UAV and the position of the base station after time Δt.

[0174] In addition to the RSRP value, the drone also needs to calculate the maximum flight distance D that each cell can provide service for based on the upcoming flight path. longest In this scheme, the RSRP threshold that can provide services is set as an absolute threshold Thr_rsrp, which is the absolute RSRP threshold value when the UAV begins its same-frequency measurement. longest This refers to the flight path length from the drone's estimated position by the computing device to the location where the drone's first measured RSRP is lower than Thr_rsrp. Therefore, based on D... longest The RSRP determines the priority of the switchable cells.

[0175] Optionally, determining the priority of the cell to be handed over based on the RSRP and the longest flight distance includes:

[0176] Using the formula: Q=ω1RSRP+ω2D longest Determine the cell handover priority factor of the cell to be handed over;

[0177] The priority of the cell to be handed over is determined based on the cell handover priority factor.

[0178] Where Q is the cell handover priority factor of the cell to be handed over, RSRP is the reference signal received power value of the cell to be handed over, and D longest The longest flight distance value of the UAV is provided for the cell to be switched, where ω1 and ω2 are weight values.

[0179] Optionally, ω1 and ω2 serve to dedimensionalize and adjust RSRP and D. longest The weights ω1 and ω2 can be based on empirical values ​​obtained from experiments, such as determining RSRP or D based on experiments. longest The importance is determined by ω1 and ω2.

[0180] Furthermore, after calculating the Q value of each cell, the cell handover list is updated according to the Q value from high to low, thus determining the priority of each cell, as shown in Table 2. Here, p represents the handover zone range where the UAV's current location is located; it is the range of a circle drawn with the UAV's current location as the origin and r as the radius, and A represents the cell location information.

[0181] Table 2

[0182]

[0183] Optionally, the drone can upload a defined cell handover list to the core network equipment, which will then save the uploaded cell handover list to the database corresponding to the path, M. m In the list M, the range p is associated with the drone switching at this moment. m The frequency f corresponding to each cell ID is preset to 0. For handover locations outside of p due to signal fluctuations or other errors, but with measured cell priority and Q, D... longest List M contains the switch points that are close to the corresponding switch band. m The values ​​of the center and radius r of the switching zone range p will be adjusted based on the drone switching position submitted this time.

[0184] Optionally, according to the activation priority, the directional antenna is activated to perform cell measurements, and the measurement results are sent to the base station.

[0185] The directional antennas are activated sequentially in descending order of activation priority to perform cell measurements, and the measurement results are sent to the base station when the measured results meet the event conditions.

[0186] For example, the drone prioritizes each switchable cell according to its own location and that of each cell to determine the activation priority of each directional antenna. First, the drone activates the highest-priority directional antenna for measurement, while simultaneously keeping the antenna corresponding to the serving cell active. If the measurement result does not meet the event conditions, the UE will close that measurement antenna port and activate the second-highest priority antenna port, continuing this process until all antenna ports are active. Since the connected drone continuously transmits services, this selective switching of measurement antenna ports reduces interference from other cells during UE measurements. When the measurement result meets the event conditions, the drone UE reports an event to the base station (gNB). The reported information may include the measurement cell ID, the measurement results of the serving cell and neighboring cells, and the D values ​​of the serving cell and neighboring cells. longest Values, etc.

[0187] Optionally, after sending the measured results to the base station, the method further includes:

[0188] Receive the handover command sent by the base station;

[0189] According to the handover command, switch from the source serving cell to the target serving cell;

[0190] The target cell handover list is updated based on the source serving cell priority information and the target serving cell identifier; or, the source serving cell priority information and the target serving cell identifier are sent to the core network equipment.

[0191] For example, the gNB evaluates the measurement results reported by the UAV, considering the UAV's regional limitations, and determines whether to initiate a handover to the target cell. After determining the handover, the base station initiates a handover request to the target cell, sending relevant information. The target cell performs admission control and reserves the resources needed by the UAV after the handover. The gNB then issues a handover command to the UAV. Upon receiving the handover command, the UAV leaves the source cell and synchronizes with the target cell. Simultaneously, it can upload the actual data corresponding to the source serving cell to the core network equipment. longest And the target cell ID for handover, so that the core network device can access the cell handover list M. m D, the community corresponding to Zhongyuan Service longest Update the Q value, and simultaneously update list M. m Increment the frequency f corresponding to the target cell by 1, and readjust the order of each cell in list M, sorting them from high to low frequency f. If f is the same, sort them from high to low Q value.

[0192] This solution involves a drone equipped with multiple directional antennas arranged in a 360° circle. During measurements before cell handover, the priority of directional antenna activation is determined based on the priority of each switchable cell in the obtained cell handover list. This allows the directional antennas to be activated gradually, avoiding 360° transmission and reception interference during drone measurements. Furthermore, this solution does not affect data service transmission during measurement intervals.

[0193] This solution uses the longest flight distance D of the drones that can provide services in each cell as the benchmark. longest Incorporating this factor into the decision-making process for the activation sequence of directional antennas can prevent access to neighboring cells with high signal strength but short service duration in a short period of time. On the one hand, this can reduce the handover frequency to avoid transmission rate troughs. On the other hand, by adjusting the directional antenna port in real time, the UAV can maintain the optimal communication direction with the serving cell, which can greatly reduce interference from such cells and improve communication performance.

[0194] This scheme is based on a cell handover list but does not depend on it; instead, it relies on actual measurements, thus exhibiting good robustness. Furthermore, by introducing the target cell frequency parameter and D... longest Feedback indicates that optimizing the cell handover list order based on historical data allows for a faster identification of suitable target cells.

[0195] The above describes the UAV-based cell measurement method according to an embodiment of the present invention. The following describes the apparatus according to an embodiment of the present invention with reference to the accompanying drawings.

[0196] like Figure 5 As shown, this embodiment of the invention provides a cell measurement device 500, applied to a drone, comprising:

[0197] The acquisition module 510 is used to acquire the target cell switching list corresponding to the flight path of the UAV;

[0198] The determining module 520 is used to determine the activation priority of multiple directional antennas on the UAV according to the target cell handover list; wherein, different directional antennas are used for beam scanning in different directions;

[0199] The first transmitting module 530 is used to activate the directional antenna to perform cell measurement according to the activation priority, and send the measurement results obtained to the base station;

[0200] The target cell handover list includes: the target handover zone range corresponding to the flight path, and the cell information and priority of the target handoverable cells corresponding to the target handover zone range.

[0201] Optionally, the acquisition module 510 includes:

[0202] The first transmitting unit is used to transmit the flight path to the core network equipment;

[0203] The first receiving unit is used to receive the target cell handover list sent by the core network equipment according to the flight path.

[0204] Optionally, the acquisition module 510 includes:

[0205] The second transmitting unit is used to transmit the flight path to the core network equipment;

[0206] The second receiving unit is configured to receive a first cell handover list sent by the core network device according to the flight path; wherein, the first cell handover list includes: a first handover band range corresponding to the flight path, cell information and priority of a first handoverable cell corresponding to the first handover band range;

[0207] The first determining unit is configured to determine the first cell handover list as the target cell handover list if the current location of the UAV is within the first handover zone.

[0208] The third receiving unit is configured to send first information to the core network device if the current location of the UAV is not within the first handover zone, and to receive the target cell list sent by the core network device based on the first information; wherein the first information includes: the current location of the UAV and related information on cell measurement.

[0209] Optionally, the acquisition module 510 includes:

[0210] The fourth receiving unit is used to receive measurement configuration information sent by the base station; wherein, the measurement configuration information includes relevant information about cell measurement;

[0211] The second determining unit is used to determine the target cell handover list based on the relevant information of the cell measurement, the current location of the UAV and the flight path.

[0212] Optionally, the acquisition module 510 includes:

[0213] The third transmitting unit is used to transmit the flight path of the UAV to the core network equipment;

[0214] The fifth receiving unit is used to receive measurement configuration information sent by the base station; wherein, the measurement configuration information includes relevant information about cell measurement;

[0215] The sixth receiving unit is configured to receive a second cell handover list sent by the core network equipment according to the flight path; wherein the second cell handover list includes: a second handover band range corresponding to the flight path, cell information and priority of the second handoverable cells corresponding to the second handover band range;

[0216] The third determining unit is used to determine the second cell handover list as the target cell handover list if the current position of the UAV is within the second handover zone.

[0217] The fourth determining unit is used to determine the target cell handover list based on the relevant information of the cell measurement, the current position of the drone, and the flight path if the current position of the drone is not within the range of the second handover zone.

[0218] Optionally, the cell measurement device 500 further includes:

[0219] The second sending module is used to send the target cell list to the core network equipment.

[0220] Optionally, the second determining unit or the fourth determining unit includes:

[0221] The first determining subunit is used to determine the location of the base station corresponding to the cell to be switched based on the relevant information measured by the cell.

[0222] The second determining subunit is used to determine the priority of the cell to be handed over based on the current location of the UAV, the location of the base station, and relevant information from the cell measurement.

[0223] The third determining subunit is used to determine the target cell handover list based on the current location of the UAV, the relevant information of the cell measurement, and the priority of the cell to be handed over.

[0224] Optionally, the second determining subunit is further configured to:

[0225] Based on the current location of the UAV, the location of the base station, and the relevant information measured by the cell, the reference signal received power (RSRP) corresponding to the cell to be handed over is determined;

[0226] Based on the flight path, determine the maximum flight distance that the cell to be switched can provide for the UAV;

[0227] The priority of the cell to be handed over is determined based on the RSRP and the longest flight distance.

[0228] Optionally, the second determining subunit is further configured to:

[0229] Based on the relevant information measured in the cell, determine the antenna pattern and transmit power of the cell to be switched over;

[0230] The antenna gain is determined based on the current location of the UAV, the location of the base station, and the antenna pattern.

[0231] The path loss of the UAV is determined based on the free space loss model;

[0232] The RSRP corresponding to the cell to be handed over is determined based on the transmit power, the antenna gain, and the path loss.

[0233] Optionally, the second determining subunit is further configured to:

[0234] Using the formula: Q=ω1RSRP+ω2D longest Determine the cell handover priority factor of the cell to be handed over;

[0235] The priority of the cell to be handed over is determined based on the cell handover priority factor.

[0236] Where Q is the cell handover priority factor of the cell to be handed over, RSRP is the reference signal received power value of the cell to be handed over, and D longest The longest flight distance value of the UAV is provided for the cell to be switched, where ω1 and ω2 are weight values.

[0237] Optionally, the first sending module 530 includes:

[0238] The fourth transmitting unit is used to sequentially activate the directional antennas to perform cell measurements according to the descending activation priority, and to send the measurement results to the base station when the measurement results meet the event conditions.

[0239] Optionally, the cell measurement device 500 further includes:

[0240] A receiving module is used to receive the handover command sent by the base station;

[0241] The handover module is used to switch from the source serving cell to the target serving cell according to the handover command;

[0242] The processing module is configured to update the target cell handover list based on the relevant information of the source serving cell priority and the target serving cell identifier; or, send the relevant information of the source serving cell priority and the cell identifier of the target serving cell to the core network equipment.

[0243] The cell measurement device in this embodiment of the invention can implement each process of the above method and achieve the same technical effect. To avoid repetition, it will not be described again here.

[0244] Another embodiment of the present invention provides a drone, such as Figure 6 As shown, it includes a transceiver 610, a processor 600, a memory 620, and a program or instructions stored in the memory 620 and executable on the processor 600; when the processor 600 executes the program or instructions, it implements the above-mentioned cell measurement method applied to the UAV side and can achieve the same technical effect. To avoid repetition, it will not be described again here.

[0245] The transceiver 610 is used to receive and send data under the control of the processor 600.

[0246] Among them, Figure 6 In this context, the bus architecture can include any number of interconnected buses and bridges, specifically linking various circuits of one or more processors represented by processor 600 and memory represented by memory 620 together. The bus architecture can also link various other circuits such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art and therefore will not be described further herein. The bus interface provides an interface. Transceiver 610 can be multiple elements, including transmitters and receivers, providing a unit for communicating with various other devices over a transmission medium. For different user equipment, user interface 630 can also be an interface capable of connecting external or internal devices, including but not limited to keypads, displays, speakers, microphones, joysticks, etc.

[0247] The processor 600 is responsible for managing the bus architecture and general processing, while the memory 620 can store the data used by the processor 600 when performing operations.

[0248] An embodiment of the present invention provides a readable storage medium storing a program or instructions. When the program or instructions are executed by a processor, they implement the steps in the cell measurement method described above and achieve the same technical effect. To avoid repetition, further details are omitted here.

[0249] The processor mentioned above is the processor in the UAV described in the above embodiments. The readable storage medium includes computer-readable storage media, such as computer read-only memory (ROM), random access memory (RAM), magnetic disk, or optical disk.

[0250] The above description focuses on the UAV side of the embodiments of the present invention. The following description, in conjunction with the accompanying drawings, describes the cell measurement method on the core network equipment side of the embodiments of the present application.

[0251] like Figure 7As shown, this embodiment of the invention provides a cell measurement method applied to core network equipment, including:

[0252] Step 71: Receive the flight path of the drone sent by the drone.

[0253] Optionally, if the drone is set to fly in a straight line, the flight path will be a set of inflection points.

[0254] Step 72: Determine the target cell handover list corresponding to the UAV based on the flight path.

[0255] The target cell handover list includes: the target handover zone range corresponding to the flight path, and the cell information and priority of the target handoverable cells corresponding to the target handover zone range.

[0256] Optionally, the multiple switchable cells in the target cell handover list corresponding to each handover band range can be arranged in descending order of the switchable cell priority. The handover band range is the range within which the UAV can perform cell handover; the switchable cells are the cells that can be switched within the handover band range, and the cell information (or target switchable cell ID set) may include: cell identifier, cell location information, and information related to the priority of the switchable cells (such as D in the following embodiment). longest The frequency f of the switchable cell being selected as the target cell for handover is shown in Table 1 of the above embodiment.

[0257] Step 73: Send the target cell handover list to the drone.

[0258] In this embodiment, the core network device sends the target cell handover list to the UAV, enabling the UAV to determine the activation priority of multiple directional antennas on the UAV based on the target cell handover list. According to the activation priority, the UAV activates the directional antennas to perform cell measurements and sends the measurement results to the base station. Thus, when the UAV interacts with the serving cell, its mobility causes the serving cell's location to change. The UAV determines the serving cell's location based on the real-time updates of the target cell handover list, promptly shutting down the original directional antenna and activating the appropriate directional antenna for data transmission and reception, maintaining optimal communication with the serving cell. By selectively activating and deactivating some antenna ports, the UAV significantly reduces transmission interference with cells in other directions. The UAV can obtain the handover priority ranking of switchable cells from the target handover cell list, and thus determine the activation priority of each directional antenna during cell measurement. It then activates only some directional antennas at the same time according to the priority order, reducing cell measurement time and significantly reducing transmission interference compared to UAV communication using omnidirectional antennas.

[0259] Optionally, determining the target cell handover list corresponding to the UAV based on the flight path includes:

[0260] Receive first information sent by the drone; wherein the first information includes: the current location of the drone and relevant information of cell measurement;

[0261] Based on the first information, determine the target cell handover list;

[0262] The list of target cells is sent to the drone.

[0263] For example, before a drone takes off, it uploads its flight path m to the core network equipment. The core network equipment then checks the database to see if a cell handover list M corresponding to flight path m exists. m If it does not exist, then based on the first information, determine the target cell handover list, such as... Figure 8 As shown.

[0264] Optionally, determining the target cell handover list corresponding to the UAV based on the flight path includes:

[0265] From the database, determine the target cell handover list corresponding to the flight path.

[0266] Optionally, the database can store cell handover lists corresponding to each flight path, and can be updated based on cell handover information and / or cell handover lists reported by the UAV. When the core network equipment receives the flight path sent by the UAV, if a target cell handover list corresponding to that flight path is matched in the database, the target handover list can be sent to the UAV. If the UAV's current location is within the handover band of the target handover list, the UAV can determine the activation priority of multiple directional antennas on the UAV based on the target cell handover list, and activate the directional antennas to perform cell measurements according to the activation priority, and send the measurement results to the base station, such as... Figure 9 As shown.

[0267] The step of determining the target cell handover list corresponding to the UAV based on the flight path includes:

[0268] From the database, determine the first cell handover list corresponding to the flight path; wherein, the first cell handover list includes: the first handover zone range corresponding to the flight path, and the cell information and priority of the first handoverable cell corresponding to the first handover zone range;

[0269] Send the first cell handover list to the drone;

[0270] Receive first information sent by the drone; wherein the first information includes: the current location of the drone and relevant information of cell measurement;

[0271] Based on the first information, the first cell handover list is updated to obtain the target cell handover list.

[0272] For example, before a drone takes off, it uploads its flight path m to the core network equipment. The core network equipment then checks the database to see if a cell handover list M corresponding to flight path m exists. m If a matching first cell handover list exists, it is sent to the UAV. If the UAV's current location is not within the handover band of the target handover list, the UAV can send first information to the core network equipment, so that the core network equipment can update the first cell handover list according to the first information to obtain the target cell handover list. The UAV can then determine the activation priority of multiple directional antennas on the UAV based on the target cell handover list, and activate the directional antennas to perform cell measurements according to the activation priority, and send the measurement results to the base station. Figure 9 As shown.

[0273] Optionally, determining the target cell handover list based on the first information includes:

[0274] Based on the relevant information measured in the cell, determine the location of the base station corresponding to the cell to be handed over;

[0275] The priority of the cell to be handed over is determined based on the current location of the drone, the location of the base station, and relevant information measured by the cell.

[0276] The target cell handover list is determined based on the current location of the UAV, the relevant information measured by the cell, and the priority of the cell to be handed over.

[0277] Optionally, determining the priority of the cell to be handed over based on the current location of the drone, the location of the base station, and relevant information from cell measurements includes:

[0278] Based on the current location of the UAV, the location of the base station, and the relevant information measured by the cell, the reference signal received power (RSRP) corresponding to the cell to be handed over is determined;

[0279] Based on the flight path, determine the maximum flight distance that the cell to be switched can provide for the UAV;

[0280] The priority of the cell to be handed over is determined based on the RSRP and the longest flight distance.

[0281] Optionally, determining the Reference Received Power (RSRP) of the cell to be handed over based on the current location of the UAV, the location of the base station, and relevant information from cell measurements includes:

[0282] Based on the relevant information measured in the cell, determine the antenna pattern and transmit power of the cell to be switched over;

[0283] The antenna gain is determined based on the current location of the UAV, the location of the base station, and the antenna pattern.

[0284] The path loss of the UAV is determined based on the free space loss model;

[0285] The RSRP corresponding to the cell to be handed over is determined based on the transmit power, the antenna gain, and the path loss.

[0286] Optionally, determining the priority of the cell to be handed over based on the RSRP and the longest flight distance includes:

[0287] Using the formula: Q=ω1RSRP+ω2D longest Determine the cell handover priority factor of the cell to be handed over;

[0288] The priority of the cell to be handed over is determined based on the cell handover priority factor.

[0289] Where Q is the cell handover priority factor of the cell to be handed over, RSRP is the reference signal received power value of the cell to be handed over, and D longest The longest flight distance value of the UAV is provided for the cell to be switched, where ω1 and ω2 are weight values.

[0290] Specifically, the core network equipment can be a UPF entity, which can store all base station information serving UAV communication, such as base station location, transmission power, cell antenna pattern information, etc.

[0291] The base station can send measurement configuration parameters to the drone via the RRCConnectionReconfiguration message. These parameters include cell measurement-related parameters such as the list of cells to be measured, reporting methods, measurement identifiers, and event parameters, so that the drone can perform measurement configuration.

[0292] When the RSRP measured by the UAV is lower than the threshold for enabling same-frequency and different-frequency measurements, it will initiate a measurement of the target object. Before measurement, the UAV uploads information such as its current location (e.g., 3D location information), flight speed, and a list of cells to be measured to the core network equipment.

[0293] Based on the drone's location and the location information of the base stations and cell antenna information corresponding to each cell in the cell list, the core network equipment calculates the RSRP values ​​that the drone should measure for each cell:

[0294] RSRP = Transmit Power + Antenna Gain θ - Path loss

[0295] The antenna gain is obtained by combining the radiation pattern of the corresponding antenna in the cell stored in the core network equipment and the azimuth angle θ of the UAV. θ is the angle between the line connecting the UAV's position and the base station's position and the antenna normal. The path loss considers the free space loss model Loss = 20lg(frequency F) + 20lg(distance d) + 32.4, where d is the distance between the UAV's position and the base station's position after time Δt.

[0296] In addition to the RSRP value, the core network equipment also needs to calculate the longest flight distance D for the drone that each cell in the cell list can provide service for, based on the drone's next flight path. longest In this scheme, the RSRP threshold for providing services is set as an absolute threshold Thr_rsrp, which is the absolute RSRP threshold value when the UE begins co-frequency measurement. longest The length of the flight path from the drone's estimated position to the location where the drone's RSRP is first measured to be lower than Thr_rsrp.

[0297] RSRP and D were calculated. longest Subsequently, the network device can return a list of cell Q-values ​​to the drone, as shown in Table 2 of the above embodiment. This allows for adjustment of the handover zone range in cases where the handover location is outside the range of p due to fluctuations. Here, p is the handover zone range of the drone's current location, defined by a circle with the drone's submitted location information as the origin and r as the radius, and A represents the cell location information. The cell Q-value list is ordered from highest to lowest based on the Q-values ​​(i.e., the cell handover priority factors for the cells being switched). The formula for calculating the Q-value is as follows:

[0298] Q = ω1RSRP + ω2D longest

[0299] Where Q is the cell handover priority factor of the cell to be handed over, RSRP is the reference signal received power value of the cell to be handed over, and D longest The longest flight distance value of the UAV is provided for the cell to be switched, where ω1 and ω2 are weight values.

[0300] Optionally, ω1 and ω2 serve to dedimensionalize and adjust RSRP and D. longest The weights ω1 and ω2 can be based on empirical values ​​obtained from experiments, such as determining RSRP or D based on experiments.longest The importance is determined by ω1 and ω2.

[0301] Optionally, the drone equipment can save the relevant information of the cell Q-value list to the cell handover list M corresponding to the path in the database. m In the list M, the range p is associated with the drone switching at this moment. m The frequency f corresponding to each cell ID is preset to 0. For handover locations outside of p due to signal fluctuations or other errors, but with measured cell priority and Q, D... longest List M contains the switch points that are close to the corresponding switch band. m The values ​​of the center and radius r of the switching zone range p will be adjusted based on the drone switching position submitted this time.

[0302] Optionally, after sending the target cell handover list to the drone, the method further includes:

[0303] Receive information related to the source serving cell priority of the drone and the cell identifier of the target serving cell sent by the drone;

[0304] The target cell handover list is updated based on the relevant information of the source serving cell priority and the cell identifier of the target serving cell.

[0305] For example, the drone prioritizes each switchable cell according to its own location and that of each cell to determine the activation priority of each directional antenna. First, the drone activates the highest-priority directional antenna for measurement, while simultaneously keeping the antenna corresponding to the serving cell active. If the measurement result does not meet the event conditions, the UE will close that measurement antenna port and activate the second-highest priority antenna port, continuing this process until all antenna ports are active. Since the connected drone continuously transmits services, this selective switching of measurement antenna ports reduces interference from other cells during UE measurements. When the measurement result meets the event conditions, the drone UE reports an event to the base station (gNB). The reported information may include the measurement cell ID, the measurement results of the serving cell and neighboring cells, and the D values ​​of the serving cell and neighboring cells. longest Values, etc.

[0306] The gNB evaluates the measurement results reported by the UAV, considering the UAV's regional limitations, and determines whether to initiate a handover to the target cell. After determining the handover, the base station initiates a handover request to the target cell, sending relevant information. The target cell performs admission control and reserves the resources needed by the UAV after the handover. The gNB then issues a handover command to the UAV. Upon receiving the handover command, the UAV leaves the source cell and synchronizes with the target cell. Simultaneously, it can upload the actual data corresponding to the source serving cell to the core network equipment. longestAnd the target cell ID for handover, so that the core network device can access the cell handover list M. m D, the community corresponding to Zhongyuan Service longest Update the Q value, and simultaneously update list M. m Increment the frequency f corresponding to the target cell by 1, and readjust the order of each cell in list M, sorting them from high to low frequency f. If f is the same, sort them from high to low Q value.

[0307] This solution involves a drone equipped with multiple directional antennas arranged in a 360° circle. During measurements before cell handover, the priority of directional antenna activation is determined based on the priority of each switchable cell in the obtained cell handover list. This allows the directional antennas to be activated gradually, avoiding 360° transmission and reception interference during drone measurements. Furthermore, this solution does not affect data service transmission during measurement intervals.

[0308] This solution uses the longest flight distance D of the drones that can provide services in each cell as the benchmark. longest Incorporating this factor into the decision-making process for the activation sequence of directional antennas can prevent access to neighboring cells with high signal strength but short service duration in a short period of time. On the one hand, this can reduce the handover frequency to avoid transmission rate troughs. On the other hand, by adjusting the directional antenna port in real time, the UAV can maintain the optimal communication direction with the serving cell, which can greatly reduce interference from such cells and improve communication performance.

[0309] This scheme is based on a cell handover list but does not depend on it; instead, it relies on actual measurements, thus exhibiting good robustness. Furthermore, by introducing the target cell frequency parameter and D... longest Feedback indicates that optimizing the cell handover list order based on historical data allows for a faster identification of suitable target cells.

[0310] The cell measurement method on the core network equipment side of the present invention has been described above. The apparatus and core network equipment of the present application embodiment will be described below with reference to the accompanying drawings.

[0311] like Figure 10 The present invention provides a cell measurement device 1000, applied to core network equipment, comprising:

[0312] The first receiving module 1010 is used to receive the flight path of the UAV sent by the UAV;

[0313] The determining module 1020 is used to determine the target cell switching list corresponding to the UAV based on the flight path;

[0314] The sending module 1030 is used to send the target cell handover list to the UAV;

[0315] The target cell handover list includes: the target handover zone range corresponding to the flight path, and the cell information and priority of the target handoverable cells corresponding to the target handover zone range.

[0316] Optionally, the determining module 1020 includes:

[0317] The first determining unit is used to determine the target cell handover list corresponding to the flight path from the database.

[0318] Optionally, the determining module 1020 includes:

[0319] The first receiving unit is configured to receive first information sent by the UAV; wherein the first information includes: the current location of the UAV and relevant information on cell measurement;

[0320] The second determining unit is used to determine the target cell handover list based on the first information;

[0321] The first sending unit is used to send the target cell list to the UAV.

[0322] Optionally, the determining module 1020 further includes:

[0323] The third determining unit is used to determine the first cell handover list corresponding to the flight path from the database; wherein, the first cell handover list includes: the first handover band range corresponding to the flight path, and the cell information and priority of the first handoverable cell corresponding to the first handover band range;

[0324] The second sending unit is used to send the first cell handover list to the drone;

[0325] The fourth determining unit is used to determine the target cell handover list based on the first information, including:

[0326] The fifth determining unit is used to update the first cell handover list based on the first information to obtain the target cell handover list.

[0327] Optionally, the second determining unit includes:

[0328] The first determining subunit is used to determine the location of the base station corresponding to the cell to be switched based on the relevant information measured by the cell.

[0329] The second determining subunit is used to determine the priority of the cell to be handed over based on the current location of the UAV, the location of the base station, and relevant information from the cell measurement.

[0330] The third determining subunit is used to determine the target cell handover list based on the current location of the UAV, the relevant information of the cell measurement, and the priority of the cell to be handed over.

[0331] Optionally, the second determining subunit is further configured to:

[0332] Based on the current location of the UAV, the location of the base station, and the relevant information measured by the cell, the reference signal received power (RSRP) corresponding to the cell to be handed over is determined;

[0333] Based on the flight path, determine the maximum flight distance that the cell to be switched can provide for the UAV;

[0334] The priority of the cell to be handed over is determined based on the RSRP and the longest flight distance.

[0335] Optionally, the second determining subunit is further configured to:

[0336] Based on the relevant information measured in the cell, determine the antenna pattern and transmit power of the cell to be switched over;

[0337] The antenna gain is determined based on the current location of the UAV, the location of the base station, and the antenna pattern.

[0338] The path loss of the UAV is determined based on the free space loss model;

[0339] The RSRP corresponding to the cell to be handed over is determined based on the transmit power, the antenna gain, and the path loss.

[0340] Optionally, the second determining subunit is further configured to:

[0341] Using the formula: Q=ω1RSRP+ω2D longest Determine the cell handover priority factor of the cell to be handed over;

[0342] The priority of the cell to be handed over is determined based on the cell handover priority factor.

[0343] Where Q is the cell handover priority factor of the cell to be handed over, RSRP is the reference signal received power value of the cell to be handed over, and D longest The longest flight distance value of the UAV is provided for the cell to be switched, where ω1 and ω2 are weight values.

[0344] Optionally, the cell measurement device 1000 further includes:

[0345] The second receiving module is used to receive information related to the source serving cell priority of the UAV and the cell identifier of the UAV when it switches to the target serving cell, which are sent by the UAV.

[0346] The update module is used to update the target cell handover list based on the relevant information of the source serving cell priority and the cell identifier of the target serving cell.

[0347] The cell measurement device in this embodiment of the invention can implement each process of the above method and achieve the same technical effect. To avoid repetition, it will not be described again here.

[0348] Embodiments of the present invention also provide a core network device, such as... Figure 11 As shown, it includes a transceiver 1110, a processor 1100, a memory 1120, and a program or instructions stored in the memory 1120 and executable on the processor 1100; when the processor 1100 executes the program or instructions, it implements the cell measurement method applied to the core network equipment described above and achieves the same technical effect. To avoid repetition, it will not be described again here.

[0349] The transceiver 1110 is used to receive and send data under the control of the processor 1100.

[0350] Among them, Figure 11 In this context, the bus architecture may include any number of interconnected buses and bridges, specifically linking various circuits together, represented by one or more processors (processor 1100) and memory (memory 1120). The bus architecture may also link together various other circuits such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art and therefore will not be described further herein. The bus interface provides an interface. The transceiver 1110 may be multiple elements, including transmitters and receivers, providing a unit for communicating with various other devices over a transmission medium. The processor 1100 is responsible for managing the bus architecture and general processing, and the memory 1120 may store data used by the processor 1100 during operation.

[0351] An embodiment of the present invention provides a readable storage medium storing a program or instructions. When the program or instructions are executed by a processor, they implement the steps in the cell measurement method described above and achieve the same technical effect. To avoid repetition, further details are omitted here.

[0352] The processor mentioned above is the processor in the core network device described in the above embodiments. The readable storage medium includes computer-readable storage media, such as computer read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0353] It should be further noted that the terminals described in this specification include, but are not limited to, smartphones, tablets, etc., and many of the functional components described are referred to as modules in order to emphasize the independence of their implementation.

[0354] In this embodiment of the invention, the module can be implemented in software so that it can be executed by various types of processors. For example, an identified executable code module may include one or more physical or logical blocks of computer instructions, which may be constructed as objects, procedures, or functions. Nevertheless, the executable code of the identified module does not need to be physically located together, but may include different instructions stored in different bits, which, when logically combined, constitute the module and achieve the module's intended purpose.

[0355] In practice, an executable code module can be a single instruction or many instructions, and can even be distributed across multiple different code segments, different programs, and across multiple memory devices. Similarly, operational data can be identified within the module and can be implemented in any suitable form and organized within any suitable type of data structure. This operational data can be collected as a single dataset or distributed across different locations (including different storage devices), and can exist, at least in part, solely as electronic signals within the system or network.

[0356] When a module can be implemented using software, considering the current level of hardware technology, modules that can be implemented in software can be implemented using hardware circuits by those skilled in the art to achieve the corresponding functions, without considering cost. These hardware circuits include conventional very-large-scale integrated circuits (VLSI) or gate arrays, as well as existing semiconductors such as logic chips and transistors, or other discrete components. Modules can also be implemented using programmable hardware devices, such as field-programmable gate arrays, programmable array logic, and programmable logic devices.

[0357] The exemplary embodiments described above are with reference to the accompanying drawings. Many different forms and embodiments are feasible without departing from the spirit and teachings of the invention. Therefore, the invention should not be construed as limiting the exemplary embodiments set forth herein. Rather, these exemplary embodiments are provided to make the invention complete and convey the scope of the invention to those skilled in the art. In these drawings, component dimensions and relative dimensions may be exaggerated for clarity. The terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. As used herein, unless clearly indicated otherwise, the singular forms “a,” “an,” and “the” are intended to include all such forms. It will be further understood that the terms “comprising” and / or “including”, when used in this specification, indicate the presence of the stated features, integers, steps, operations, components, and / or elements, but do not exclude the presence or addition of one or more other features, integers, steps, operations, components, and / or groups thereof. Unless otherwise indicated, when stated, a range of values ​​includes the upper and lower limits of the range and any subranges in between.

[0358] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A cell measurement method, applied to unmanned aerial vehicles (UAVs), characterized in that, include: Obtain the target cell switching list corresponding to the drone's flight path; Based on the target cell handover list, the activation priority of multiple directional antennas on the UAV is determined; wherein, different directional antennas are used for beam scanning in different directions; According to the activation priority, the directional antenna is activated to perform cell measurements, and the measurement results are sent to the base station. The target cell handover list includes: the target handover zone range corresponding to the flight path, cell information and priority of the target handoverable cells corresponding to the target handover zone range; the multiple handoverable cells in the target cell handover list corresponding to each handover zone range are arranged in descending order of priority of the handoverable cells. The step of activating the directional antenna to perform cell measurement according to the activation priority and sending the measurement results to the base station includes: The directional antennas are activated sequentially in descending order of activation priority to perform cell measurements, and the measurement results are sent to the base station when the measured results meet the event conditions. The step of sequentially activating the directional antennas for cell measurement according to the descending priority order, and sending the measurement results to the base station when the measurement results meet the event conditions, includes: The UAV sorts the available cells according to their priorities and obtains the activation priority of each directional antenna based on its own location information and that of each cell. The UAV first activates the highest priority directional antenna to perform measurements while keeping the antenna corresponding to the serving cell active. If the measurement result meets the event conditions, the measurement result is reported to the base station. If the measurement result does not meet the event conditions, the UAV closes the measurement antenna port and activates the second priority antenna port, until all antenna ports are activated. The drone determines the location of the serving cell in real time by updating the target cell switching list, turns off the original directional antenna, and turns on the target directional antenna to transmit and receive data.

2. The method according to claim 1, characterized in that, The acquisition of the target cell handover list corresponding to the drone's flight path includes: The flight path is sent to the core network equipment; Receive the target cell handover list sent by the core network equipment according to the flight path.

3. The method according to claim 1, characterized in that, The acquisition of the target cell handover list corresponding to the drone's flight path includes: The flight path is sent to the core network equipment; The system receives a first cell handover list sent by the core network device according to the flight path; wherein the first cell handover list includes: a first handover band range corresponding to the flight path, cell information and priority of a first handoverable cell corresponding to the first handover band range; If the current location of the drone is within the first handover zone, then the first cell handover list is determined to be the target cell handover list; If the current location of the UAV is not within the first handover zone, the first information is sent to the core network device, and the target cell handover list sent by the core network device according to the first information is received; wherein, the first information includes: the current location of the UAV and related information of cell measurement.

4. The method according to claim 1, characterized in that, The acquisition of the target cell handover list corresponding to the drone's flight path includes: Receive measurement configuration information sent by the base station; wherein, the measurement configuration information includes relevant information about cell measurement; Based on the relevant information measured in the cell, the current location of the UAV, and the flight path, the target cell handover list is determined.

5. The method according to claim 1, characterized in that, The acquisition of the target cell handover list corresponding to the drone's flight path includes: The flight path of the UAV is sent to the core network equipment, and measurement configuration information is received from the base station; wherein, the measurement configuration information includes relevant information on cell measurement; The system receives a second cell handover list sent by the core network device according to the flight path; wherein the second cell handover list includes: a second handover band range corresponding to the flight path, cell information and priority of the second handoverable cells corresponding to the second handover band range; If the current location of the drone is within the second handover zone, then the second cell handover list is determined to be the target cell handover list; If the current location of the UAV is not within the second handover zone, the target cell handover list is determined based on the relevant information measured by the cell, the current location of the UAV, and the flight path.

6. The method according to claim 4 or 5, characterized in that, Also includes: The target cell handover list is sent to the core network equipment.

7. The method according to claim 4 or 5, characterized in that, The step of determining the target cell handover list based on the relevant information measured by the cell, the current location of the UAV, and the flight path includes: Based on the relevant information measured in the cell, determine the location of the base station corresponding to the cell to be handed over; The priority of the cell to be handed over is determined based on the current location of the drone, the location of the base station, and relevant information measured by the cell. The target cell handover list is determined based on the current location of the UAV, the relevant information measured by the cell, and the priority of the cell to be handed over.

8. The method according to claim 7, characterized in that, The step of determining the priority of the cell to be handed over based on the current location of the drone, the location of the base station, and relevant information measured by the cell includes: Based on the current location of the UAV, the location of the base station, and the relevant information measured by the cell, the reference signal received power (RSRP) corresponding to the cell to be handed over is determined; Based on the flight path, determine the maximum flight distance that the cell to be switched can provide for the UAV; The priority of the cell to be handed over is determined based on the RSRP and the longest flight distance.

9. The method according to claim 8, characterized in that, The step of determining the Reference Received Power (RSRP) corresponding to the cell to be handed over based on the current location of the UAV, the location of the base station, and relevant information from the cell measurements includes: Based on the relevant information measured in the cell, determine the antenna pattern and transmit power of the cell to be switched over; The antenna gain is determined based on the current location of the UAV, the location of the base station, and the antenna pattern. The path loss of the UAV is determined based on the free space loss model; The RSRP corresponding to the cell to be handed over is determined based on the transmit power, the antenna gain, and the path loss.

10. The method according to claim 8, characterized in that, The step of determining the priority of the cell to be handed over based on the RSRP and the longest flight distance includes: Through the formula: Determine the cell handover priority factor of the cell to be handed over; The priority of the cell to be handed over is determined based on the cell handover priority factor. Where Q is the cell handover priority factor of the cell to be handed over, and RSRP is the reference signal received power value of the cell to be handed over. Provide the longest flight distance value of the UAV for the cell to be switched. and This is the weight value.

11. The method according to claim 1, characterized in that, After sending the measurement results to the base station, the process further includes: Receive the handover command sent by the base station; According to the handover command, switch from the source serving cell to the target serving cell; The target cell handover list is updated based on the source serving cell priority information and the target serving cell identifier; or, the source serving cell priority information and the target serving cell identifier are sent to the core network equipment.

12. A cell measurement device, applied to an unmanned aerial vehicle (UAV), characterized in that, include: The acquisition module is used to obtain the target cell switching list corresponding to the drone's flight path; The determination module is used to determine the activation priority of multiple directional antennas on the UAV based on the target cell handover list; wherein, different directional antennas are used for beam scanning in different directions; The first transmitting module is used to activate the directional antenna to perform cell measurement according to the activation priority, and send the measurement results to the base station. The target cell handover list includes: the target handover zone range corresponding to the flight path, cell information and priority of the target handoverable cells corresponding to the target handover zone range; the multiple handoverable cells in the target cell handover list corresponding to each handover zone range are arranged in descending order of priority of the handoverable cells. The first sending module includes: The fourth transmitting unit is used to sequentially activate the directional antennas to perform cell measurements according to the descending activation priority, and to send the measurement results to the base station when the measurement results meet the event conditions. The step of sequentially activating the directional antennas for cell measurement according to the descending priority order, and sending the measurement results to the base station when the measurement results meet the event conditions, includes: The UAV sorts the available cells according to their priorities and obtains the activation priority of each directional antenna based on its own location information and that of each cell. The UAV first activates the highest priority directional antenna to perform measurements while keeping the antenna corresponding to the serving cell active. If the measurement result meets the event conditions, the measurement result is reported to the base station. If the measurement result does not meet the event conditions, the UAV closes the measurement antenna port and activates the second priority antenna port, until all antenna ports are activated. The drone determines the location of the serving cell in real time by updating the target cell switching list, turns off the original directional antenna, and turns on the target directional antenna to transmit and receive data.

13. An unmanned aerial vehicle (UAV), comprising: A transceiver, a processor, a memory, and a program or instructions stored in the memory and executable on the processor; characterized in that, when the processor executes the program or instructions, it implements the steps of the cell measurement method as described in any one of claims 1 to 11.

14. A readable storage medium having a program or instructions stored thereon, characterized in that, When the program or instructions are executed by the processor, they implement the steps in the cell measurement method as described in any one of claims 1 to 11.

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