Positioning method and communication device

Abstract

A positioning method and a communication device are provided. In the method, a terminal device determines a first TA between the terminal device and an access network device at a first time point, and transmits a first parameter corresponding to the first TA to the network device. The terminal device determines a second TA between the terminal device and the access network device at a second time point, and transmits a second parameter corresponding to the second TA to the network device. The network device positions the terminal device based on the first parameter and the second parameter, or the network device transmits the first parameter and the second parameter to another network device to position the terminal device. In this method, the terminal device can be positioned based on the communication between the terminal device and one network device, so that the method can be applied to a satellite communication scenario to solve the problem of positioning the terminal device when the terminal device can only be covered by one satellite.

Description

Technical Field

[0001] This application relates to the field of wireless communication, and more particularly to positioning methods and communication devices.

Background Art

[0003] Compared with terrestrial communication, satellite communication has its own advantages. For example, satellite communication can provide a wider coverage area, and satellite base stations are not vulnerable to natural disasters or external forces. If satellite communication is introduced into the future 5G communication system, communication services can be provided in some areas that cannot be covered by terrestrial communication networks, such as the ocean or forest, the reliability of the 5G communication system can be enhanced, for example, users on an airplane or a train can be ensured to obtain better communication services, and more resources for data transmission can be provided to the 5G communication system due to the increase in network speed. Therefore, supporting both terrestrial communication and satellite communication is the development direction of the future 5G communication system, which has great advantages in terms of wide coverage, reliability, multi-connection, high throughput, etc.

[0004] Currently, satellite communication has been introduced into the 3GPP standard and is used as a communication scenario for 5G communication. In this standard, timing technology, synchronization technology, HARQ technology, and other technologies have been enhanced to adapt to the characteristics of large delay and high mobility. However, in existing terrestrial communication, the network side can complete the positioning of the terminal device or verify the location reported by the terminal device. However, the 3GPP satellite communication system does not have this function. Therefore, how to verify the location reported by the terminal device by the communication satellite and further position the terminal device will be the research direction in the future.

Summary of the Invention

[0005] Embodiments of the present invention provide a positioning method and a communication device for positioning a terminal device.

[0006] According to a first aspect, an embodiment of the present application provides a positioning method, which includes a terminal device determining a first timing advance time (TA) between the terminal device and an access network device at a first time point. The terminal device transmits a first parameter corresponding to the first TA to a network device. The terminal device determines a second TA between the terminal device and an access network device at a second time point. The terminal device transmits a second parameter corresponding to the second TA to a network device, thereby allowing the network device to position the terminal device based on the first and second parameters, or the network device to transmit the first and second parameters to another network device.

[0007] In the aforementioned embodiments of this application, the terminal device transmits a first parameter corresponding to a first TA at a first time point and a second parameter corresponding to a second TA at a second time point to a network device, thereby enabling the network device, or another network device configured to position the terminal device, to position the terminal device based on the first and second parameters. This method can be applied to satellite communication scenarios to solve the problem of positioning a terminal device when it is possible for the terminal device to be covered by only one satellite. Furthermore, trigger conditions can be set for the terminal device to report the second parameter. In addition, since the accuracy of the TA may be inconsistent with the accuracy of the corresponding parameter, the difference between the corresponding parameter and the TA may be further reported to improve the accuracy of the reported TA and thus improve positioning accuracy.

[0008] In possible implementations, the difference between the second TA and the first TA is within a pre-configured range. In the aforementioned implementation, corresponding trigger conditions are set for the terminal device to report the second parameter, thereby causing the terminal device to report the first and second parameters that satisfy the pre-configured conditions. Based on the first parameter, the second parameter, and a pre-configured threshold, the network device can determine a more accurate TA difference to improve positioning accuracy. The trigger conditions may be configured by the network device or pre-agreed upon in the protocol.

[0009] In possible implementations, the difference between the second TA and the first TA, and the difference between the second parameter and the first parameter, are within a pre-set range. In the aforementioned implementations, similarly, corresponding trigger conditions are set for the terminal device to report the second parameter, thereby causing the terminal device to report the first and second parameters that satisfy the pre-set conditions. The network device can then determine a more accurate TA difference based on the first parameter, the second parameter, and a pre-set threshold, thereby improving positioning accuracy.

[0010] In possible implementations, the difference between the second time point and the first time point is within a predetermined range. The difference between the first and second time points is the travel time of the network device (satellite). Generally, if the travel time of the network device is within a predetermined range, then accordingly, the difference between the second TA and the first TA is also within the required range, thereby enabling the network device or another device to position the terminal device.

[0011] In possible implementations, this method further includes the terminal device transmitting a first difference and a second difference to a network device, wherein the difference between the first difference and the difference between a first parameter and a first TA is within a predetermined range, and the difference between the second difference and the difference between a second parameter and a second TA is within a predetermined range, thereby allowing the network device to position the terminal device based on the first parameter, the first difference, the second parameter, and the second difference, or the network device transmitting the first parameter, the first difference, the second parameter, and the second difference to another network device. Alternatively, the terminal device transmits a TA difference to a network device, wherein the difference between the TA difference and the difference between a first TA and a second TA is within a predetermined range, thereby allowing the network device to position the terminal device based on the first parameter, the second parameter, and the TA difference, or the network device transmitting the first parameter, the second difference, and the TA difference to another network device. The terminal device transmits the first difference and the second difference to the network device, which in turn allows the network device to determine a more accurate TA and position the terminal device more accurately.

[0012] In a possible implementation, the Time Arrangement (TA) is the deviation between uplink and downlink subframes, obtained by the terminal device by measuring the uplink and downlink signals. For example, the terminal device measures the time difference between downlink subframe i and uplink subframe i and uses that time difference as the TA. In another possible implementation, the TA is determined by the terminal device based on the location of the network device relative to the terminal device.

[0013] According to a second aspect, the present application provides a positioning method, the method comprising: a network device receiving a first parameter transmitted by a terminal device, the first parameter being a parameter corresponding to a first timing advance TA between the terminal device and an access network device at a first time point; the network device receiving a second parameter transmitted by the terminal device, the second parameter being a parameter corresponding to a second TA between the terminal device and an access network device at a second time point; the network device positioning the terminal device based on the first and second parameters, or transmitting the first and second parameters to another network device, thereby allowing the other network device to position the terminal device based on the first and second parameters, or transmitting the first and second parameters to a network device configured to position the terminal device.

[0014] In possible implementations, the difference between the second TA and the first TA is a pre-set threshold.

[0015] In possible implementations, the difference between the second TA and the first TA, and the difference between the second parameter and the first parameter, are within a predetermined range.

[0016] In possible implementations, this method further includes a network device receiving a first difference and a second difference transmitted by a terminal device, wherein the difference between the first difference and the difference between a first parameter and a first TA is within a predetermined range, and the difference between the second difference and the difference between a second parameter and a second TA is within a predetermined range. Positioning the terminal device based on the first and second parameters by the network device includes the network device determining a first TA based on the first difference and the first parameter, the network device determining a second TA based on the second difference and the second parameter, and the network device positioning the terminal device based on the first and second TAs. Alternatively, this method further includes the network device transmitting the first difference and the second difference to another network device.

[0017] In possible implementations, this method further includes a network device receiving a TA difference transmitted by a terminal device, and ensuring that the difference between the TA difference and the difference between a first TA and a second TA is within a pre-defined range. The network device positioning a terminal device based on a first parameter and a second parameter includes the network device positioning the terminal device based on the first parameter, the second parameter, and the TA difference. Alternatively, this method further includes the network device transmitting the TA difference to another network device.

[0018] According to a third aspect, the present application provides a positioning method, the method comprising a terminal device receiving a first common timing advance TA broadcast by a network device. The terminal device transmits a first reference signal to the network device based on the first common TA. The terminal device receives a second common TA broadcast by the network device. The terminal device transmits a second reference signal to the network device based on the second common TA, so that the network device can position the terminal device based on the actual reception time of the first reference signal, a time determined based on the first common TA, the actual reception time of the second reference signal, and a time determined based on the second common TA.

[0019] In the embodiment described above, the terminal device transmits a reference signal to the network device based on a common TA broadcast by the network device. Since there is a residual TA between the common TA broadcast by the network device and the TA actually required by the terminal device, the network device can determine the difference between the distances from the terminal device to the network device at different points in time based on the residual TAs at different points in time, and estimate the location information of the terminal device. This method can be applied to satellite communication scenarios to solve the problem of positioning a terminal device when it is possible for the terminal device to be covered by only one satellite.

[0020] In possible implementations, the first common TA includes the first feeder TA and the first service link TA, and the second common TA includes the second feeder TA and the second service link TA. Alternatively, the first common TA includes the first service link TA, and the second common TA includes the second service link TA.

[0021] According to a fourth aspect, the present application provides a positioning method, which includes a network device broadcasting a first common timing advance TA. The network device receives a first reference signal transmitted by a terminal device based on the first common TA. The network device broadcasts a second common TA. The network device receives a second reference signal transmitted by a terminal device based on the second common TA. The network device positions the terminal device based on the actual reception time of the first reference signal, a time determined based on the first common TA, the actual reception time of the second reference signal, and a time determined based on the second common TA.

[0022] In possible implementations, the first common TA includes the first feeder TA and the first service link TA, and the second common TA includes the second feeder TA and the second service link TA. Alternatively, the first common TA includes the first service link TA, and the second common TA includes the second service link TA.

[0023] According to a fifth aspect, the present application provides a positioning method comprising a terminal device transmitting a first message to a network device through a first beam; the terminal device transmitting a second message to the network device through a second beam, thereby the network device positioning the terminal device based on the direction of the beam for receiving the first message and the direction of the beam for receiving the second message.

[0024] In the embodiments described above, the terminal device transmits a message to the network device through a separate beam, thereby allowing the network device to determine the orientation of the terminal device based on the direction of the beam for reception. This method can be applied to satellite communication scenarios, particularly GEO scenarios, to solve the problem that terminal devices cannot be positioned based on TA due to the satellite being stationary relative to the ground. Furthermore, separate configuration parameters such as time-frequency resources, scrambling / descrambling scheme, polarization scheme, and common TA can be configured for the separate beam, thereby allowing the network device to determine the beam for receiving the message transmitted by the terminal device.

[0025] In possible implementations, the scrambling scheme used by the terminal device on the first beam is different from the scrambling scheme used on the second beam. Alternatively, the time-frequency resources used by the terminal device to transmit the first message on the first beam are different from the time-frequency resources used to transmit the second message on the second beam. Alternatively, the polarization scheme used by the terminal device on the first beam is different from the polarization scheme used on the second beam.

[0026] In possible implementations, this method further includes the terminal device receiving a first common timing advance TA through a first beam, and the terminal device receiving a second common TA through a second beam, wherein the second common TA is different from the first common TA. The terminal device sending a first message to a network device through the first beam includes the terminal device sending a first message to a network device through the first beam based on the first common TA. The terminal device sending a second message to a network device through a second beam includes the terminal device sending a second message to a network device through the second beam based on the second common TA.

[0027] According to the sixth aspect, the present application provides a positioning method. This method includes a network device receiving a first message transmitted by a terminal device through a first beam. The network device receives a second message transmitted by the terminal device through a second beam. The network device positions the terminal device based on the pointing direction of the first beam and the pointing direction of the second beam.

[0028] In a possible implementation, the descrambling method of the network device on the first beam is different from the descrambling method on the second beam. Alternatively, the time-frequency resources for the network device to receive the first message on the first beam are different from the time-frequency resources for receiving the second message on the second beam. Alternatively, the polarization method used by the network device on the first beam is different from the polarization method used on the second beam.

[0029] In a possible implementation, this method further includes the network device transmitting a first common timing advance TA through the first beam, the network device transmitting a second common TA through the second beam, and the second common TA being different from the second common TA. The network device receiving the first message transmitted by the terminal device through the first beam includes the network device receiving the first message transmitted by the terminal device through the first beam based on the first common TA. The network device receiving the second message transmitted by the terminal device through the second beam includes the network device receiving the second message transmitted by the terminal device through the second beam based on the second common TA.

[0030] According to a seventh aspect, an embodiment of the present application provides a communication device including a processor, a memory, and a communication interface separately coupled to the processor. The communication interface is configured to communicate with another device. The processor is configured to operate instructions or programs in the memory and execute a positioning method according to any one of the first aspect and possible implementations of the first aspect, any one of the third aspect and possible implementations of the third aspect, or any one of the fifth aspect and possible implementations of the fifth aspect through the communication interface.

[0031] According to an eighth aspect, an embodiment of the present application provides a communication device including a processor, a memory, and a communication interface separately coupled to the processor. The communication interface is configured to communicate with another device. The processor is configured to operate instructions or programs in the memory and execute a positioning method according to any one of the second aspect and possible implementations of the second aspect, any one of the fourth aspect and possible implementations of the fourth aspect, or any one of the sixth aspect and possible implementations of the sixth aspect through the communication interface.

[0032] According to a ninth aspect, an embodiment of the present application provides a computer-readable storage medium storing computer-readable instructions. When the computer-readable instructions run on a computer, a method according to any one of the first aspect to the sixth aspect and possible implementations is executed.

[0033] According to a tenth aspect, an embodiment of the present application provides a computer program product including instructions. When the computer program product runs on a computer, a method according to any one of the first aspect to the sixth aspect and possible implementations is executed. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] [Figure 1]This is a diagram of the UL-TOA algorithm according to an embodiment of this application. [Figure 2] This is a diagram of the UL-TDOA algorithm according to an embodiment of this application. [Figure 3] This is a diagram of the UL-AOA algorithm according to an embodiment of this application. [Figure 4a] This is a diagram illustrating an application scenario for satellite communications according to the embodiments of this application. [Figure 4b] This is a diagram illustrating an application scenario for satellite communications according to the embodiments of this application. [Figure 4c] This is a diagram illustrating an application scenario for satellite communications according to the embodiments of this application. [Figure 5] This is a schematic flowchart of the positioning method according to the embodiment of this application. [Figure 6] This is a diagram of a terminal device (TA) at a different point in time according to an embodiment of the present application. [Figure 7] This is a schematic flowchart of another positioning method according to an embodiment of this application. [Figure 8] This figure illustrates the transmission of a reference signal by a terminal device at a separate point in time, according to an embodiment of the present application. [Figure 9] This is a schematic flowchart of yet another positioning method according to an embodiment of this application. [Figure 10] This is a diagram showing the direction of a separate beam according to an embodiment of the present application. [Figure 11] This is a diagram showing the structure of a communication device according to an embodiment of this application. [Figure 12] This is a diagram showing the structure of another communication device according to an embodiment of this application. [Modes for carrying out the invention]

[0035] There are several methods for positioning terminal devices in terrestrial communication networks. For example, terminal devices are positioned based on factors such as the delay of the reference signal, the delay difference, and the reception angle. Several common positioning methods are described individually below.

[0036] - Uplink arrival time (UL-TOA) method

[0037] Each of the multiple base stations measures the arrival time of the received reference signal transmitted by the terminal device and calculates the distance between the base station and the terminal device based on the arrival time and the speed of light. Each base station draws a circle with the base station as the center and the distance between the base station and the terminal device as the radius, as shown in Figure 1. The location of the terminal device is then estimated using a positioning algorithm such as a trilateral positioning algorithm or a least-squares algorithm.

[0038] - Uplink time difference of arrival (UL-TDOA) method

[0039] A disadvantage of the UL-TOA method is that if the time is not synchronized between the base station and the terminal device, neither the base station nor the terminal device knows the absolute time for transmitting the signal, leading to calculation and positioning errors.

[0040] However, in the UL-TDOA method, the difference in distances between a terminal device and two base stations is calculated by measuring the difference in signal arrival times between the terminal device and the two base stations. From a mathematical standpoint, the terminal device is positioned on a hyperbola that uses the difference in distances between the terminal device and the two base stations as foci and uses the difference in distances between the terminal device and the two base stations as a fixed difference. The locations of the terminal device and multiple base stations lie on a hyperbola that uses the difference in distances as a fixed difference and uses the difference in distances as foci. Based on the principle described above, multiple hyperbolas can be obtained by using three or more base stations around the terminal device. As shown in Figure 2, the intersection of these hyperbolas may be the location of the terminal device.

[0041] - Uplink angle of arrival (UL-AOA) method

[0042] The base station measures the angles of arrival, for example θ1, -θ2, θ3, and -θ4 in Figure 3, based on the beam used by the terminal device to transmit a reference signal, and then transmits the angles of arrival obtained through the measurements to the network device used for positioning. The network device positions the terminal device based on the location of each base station and the angles of arrival obtained through the measurements by the base station.

[0043] - Reference signal received power (RSRP) method

[0044] The power values ​​of the reference signal reflected by the terminal device are measured when it is received by multiple surrounding base stations. Based on the measured power, the ratio of the distances between the terminal device and the multiple base stations can be determined. Then, the terminal device is positioned based on the location of each base station and the ratio of the distances between the terminal device and the multiple base stations.

[0045] However, in satellite communication scenarios, the distance between the terminal device and the satellite is very long, resulting in significant transmission delay. The terminal device compensates for the transmission delay by determining a timing advance (TA) and performing a pre-transmission based on the determined TA. The terminal device can report the determined TA to the satellite. However, the terminal device reports the TA in slot units, which is coarse in granularity. For example, if the actual TA is 5.5 ms, the terminal device reports the TA in slot units, and with a subcarrier spacing of 15 kHz, one slot is 1 ms. In this case, the terminal device reports 6 TA slots. When the terminal device is positioned based on the TA reported by the terminal device and based on the UL-TOA or UL-TDOA method, the error is large.

[0046] However, when the UL-AOA method is used for positioning, the base station needs to measure the angle of arrival based on the antenna array. Currently, satellites typically use parabolic antennas instead of antenna arrays. Therefore, the UL-AOA method is not applicable to positioning terminal devices in satellite communication scenarios.

[0047] Because the distance between the terminal device and the satellite is very long, the difference between RSRPs is very small, resulting in high detection ambiguity. Therefore, the RSRP method is not applicable to positioning terminal devices in satellite communication scenarios.

[0048] Furthermore, all of the aforementioned methods depend on the case where multiple base stations receive a reference signal transmitted by the terminal device for measurement. However, in satellite communication scenarios, it is rare for a terminal device to be located within the coverage area of ​​multiple satellites. Therefore, positioning a terminal device performed jointly by multiple satellites has significant limitations.

[0049] It can be understood that general ground-based terminal device positioning methods cannot be directly applied to satellite communication scenarios. Taking this into consideration, embodiments of this application provide a positioning method that can be applied to satellite communication scenarios to satisfy the requirements for positioning terminal devices in satellite communication scenarios.

[0050] Figures 4a, 4b, and 4c provide examples of possible application architectures for satellite communications. The positioning method provided in the embodiments of this application can be applied to any of the network architectures shown in Figures 4a, 4b, and 4c.

[0051] In the architecture shown in Figure 4a, base stations are deployed on the ground, satellites are connected to gateways via air interfaces, and gateways can be connected to base stations via wireless or wired links. Ground-based terminal devices access the mobile communication network through air interfaces (various types of air interfaces, for example, a 5G air interface), and satellites are used as transmission nodes for transferring information about terminal devices.

[0052] In the architecture shown in Figure 4b, a base station is deployed on a satellite, the satellite is connected to a gateway via an air interface, and the gateway may be connected to the core network via a wireless or wired link. Ground-based terminal devices communicate with the satellite base station via the air interface to access the mobile communication network. As a base station, the satellite is connected to the gateway via the NG interface of the air interface, and the gateway is connected to the core network via the NG interface. The NG interface may be in wireless or wired form.

[0053] Compared to the architecture shown in Figure 4b, the architecture shown in Figure 4c includes a communication scenario between satellite base stations. Specifically, the satellite base stations can communicate with each other through the Xn interface.

[0054] In Figures 4a to 4c, the terminal devices may include various types of terminal devices that support the new radio, such as mobile phones, tablet computers, in-vehicle terminal devices, and wearable terminal devices. The terminal devices may access the satellite network through the air interface and initiate services such as calls or internet access.

[0055] Base stations are primarily configured to provide wireless access services, schedule wireless resources for accessing terminal devices, and offer reliable wireless transmission protocols, data encryption protocols, and the like.

[0056] The core network is primarily configured to provide functions such as user access control, mobility management, session management, user security authentication, and billing. The core network includes multiple functional units, which can be classified into control plane functional entities and data plane functional entities. Access and Mobility Management (AMF) entities are configured to handle user access management, security authentication, mobility management, etc. User Plane Functional (UPF) entities are configured to handle functions such as managing user plane data transmission and traffic statistics.

[0057] Gateways are primarily responsible for transferring signaling and service data between satellites and base stations, or between satellites and the core network.

[0058] An air interface refers to the wireless link between a terminal device and a base station.

[0059] The Xn interface refers to an interface between satellite base stations and is primarily used for signaling exchanges such as handovers.

[0060] An NG interface refers to an interface between a base station and the core network, an interface between a gateway and the core network, or an interface between a satellite base station and a gateway (in this case, the interface is a radio link), and is primarily used for exchanging signaling data such as NAS signaling of the core network and user service data.

[0061] Figure 5 is a schematic flowchart of a positioning method according to an embodiment of this application. This positioning method can be applied to satellite communication scenarios, particularly non-geostationary earth orbit (NGEO) satellite communication scenarios or unmanned aerial vehicle (UAV) communication scenarios. The UAV communication scenario is similar to the satellite communication scenario. For ease of description, the satellite communication scenario will be used as an example hereafter.

[0062] In the NGEO satellite communication scenario, the distance between the terminal device and the satellite constantly changes as the satellite moves relative to the ground. Because this distance constantly changes, the transmission delay between the terminal device and the satellite also constantly changes. The terminal device can compensate for the transmission delay by adjusting the timeout (TA) as the distance changes. The positioning method shown in Figure 5 is to position the terminal device by using a procedure in the satellite communication scenario in which the terminal device reports the TA.

[0063] As shown in Figure 5, this positioning method may include the following steps.

[0064] Step 501: The terminal device determines the first TA between the terminal device and the access network device at a first point in time.

[0065] When this method is applied to the network architecture shown in Figure 4a, Figure 4b, or Figure 4c, the access network device here may be a satellite shown in Figure 4b or Figure 4c used as a base station, or a ground base station shown in Figure 4a.

[0066] In the NGEO scenario, the satellite moves relative to the ground. Therefore, the distance between the terminal device and the satellite can differ at different points in time. However, different distances result in different transmission delays for communications between the terminal device and the satellite. The terminal device determines the Time Attack (TA) at a first point in time. To distinguish it from TAs at other points in time, the TA at the first point in time is called the first TA.

[0067] The methods for determining the Time Arrangement (TA) by a terminal device are not limited in this embodiment of the present application. For details, see any existing TA determination methods. For example, if a satellite is used as a base station and the uplink synchronization reference point is on the base station, the terminal device determines the round-trip transmission delay between the terminal device and the satellite based on the satellite's location (which may be obtained through ephemeris-based calculations) and the terminal device's location (which may be obtained based on a global navigation satellite system (GNSS)). If the satellite is used as a transmission node, the base station is on the ground and the uplink synchronization reference point is on the base station. The TA includes not only the round-trip transmission delay between the terminal device and the satellite, but also the round-trip transmission delay between the satellite and the ground base station. The transmission delay between the satellite and the ground base station is generally communicated to the terminal device by the network device. If the satellite is used as a base station but the synchronization reference point is not on the base station, the TA may include the round-trip transmission delay between the terminal device and the satellite, and the round-trip transmission delay between the satellite and the synchronization reference point. The delay between the satellite and the synchronization reference point is generally communicated to the terminal device by the network device (satellite). As another example, the terminal device may measure the time difference between a downlink subframe i and an uplink subframe i and use that time difference as the time interval (TA).

[0068] Step 502: The terminal device sends the first parameter corresponding to the first TA to the network device.

[0069] Network devices as used herein may include, but are not limited to, base stations (gNB), access and mobility management function (AMF) network elements, and location management function (LMF) in 5G communication systems, as well as base stations (eNB), transmission points (TP), transmission reception points (TRP), and gateways (GW) in 4G communication systems.

[0070] When this method is applied to the network architecture shown in Figure 4a, the network devices may be satellites, gateways, base stations, or devices in the core network. When this method is applied to the network architecture shown in Figure 4b or Figure 4c, the network devices may be satellite base stations, gateways, or devices in the core network.

[0071] The terminal device transmits a first parameter corresponding to a first TA to the network device, thereby enabling the network device or another device to position the terminal device based on the first parameter. For example, the network device may determine the difference between the distances between the terminal device and the access network device at multiple points in time based on the parameters corresponding to the TA at multiple points in time, and perform positioning based on that distance difference.

[0072] The terminal device may report the first parameter in multiple reporting methods.

[0073] In possible implementations, the first parameter may be in slot units. Currently, terminal devices typically report TAs in slot units. In this case, the terminal device determines the number of first slots corresponding to the first TA, i.e., the first parameter. It is assumed that the first TA determined by the terminal device is 4.4 ms. If the subcarrier spacing is 15 kHz, then one slot is 1 ms. In this case, 4.4 ms corresponds to 5 slots. In other words, the first parameter is 5 slots. In this scheme, when reporting the first parameter corresponding to the first TA, the terminal device can transmit the first parameter based on an existing signaling format, with little modification to existing communication standards.

[0074] In other possible implementations, the first parameter may be in units such as milliseconds or microseconds. If the units of the first TA determined by the terminal device are the same as the units of the reported first parameter, for example, if both the first TA and the first parameter are in milliseconds, then the determined first parameter is the first TA. Alternatively, the first parameter may be obtained by rounding the first TA. For example, if the first TA determined by the terminal device is 5.6ms and 5.6ms is rounded up to 6ms, then the first parameter is 6ms.

[0075] Alternatively, the terminal device may determine the first parameter corresponding to the first TA in another pre-agreed manner. This is not limited to this embodiment of the present application.

[0076] Optionally, when transmitting the first parameter to the network device, the terminal device may further transmit display information indicating the first time point to the network device, thereby allowing the network device to determine the location information of the access network device at the first time point, and to position the terminal device in subsequent operations based on the location information of the access network device at the first time point and the first parameter.

[0077] Step 503: The terminal device determines the second TA between the terminal device and the access network device at the second time point.

[0078] In the scenarios shown in Figures 4a, 4b, or 4c, the satellite moves relative to the ground, so the distance between the terminal device and the satellite at a second time point may differ from the distance between the terminal device and the satellite at a first time point, and therefore the TAs will also differ. For example, as shown in Figure 6, the TA of the terminal device at time t1 is TA1, the TA at time t2 is TA2, the TA at time t3 is TA3, and the TA at time t4 is TA4. Only the distance between the terminal device and the satellite at a first time point can be determined based solely on the TA at the first time point, but the location of the terminal device cannot be determined. In this case, the terminal device further needs to determine the TA at a second time point, calculate the distance between the terminal device and the satellite at the second time point, or calculate the difference between the distance at the first time point and the distance at the second time point in order to determine the location information of the terminal device. For ease of distinction, the TA determined at a second time point is referred to as the second TA.

[0079] The method by which the terminal device determines the second TA at the second time point is the same as the method by which the terminal device determines the first TA at the first time point. Further details will not be described here.

[0080] When the terminal device is in motion, a large interval between the first and second time points is inappropriate, as the movement of the terminal device will result in a large displacement of the terminal device. Optionally, the interval between the second and first time points may be set to be within a predetermined time range to ensure the accuracy of positioning the terminal device.

[0081] Step 504: The terminal device sends a second parameter corresponding to the second TA to the network device.

[0082] The terminal device transmits a second parameter corresponding to the second TA to the network device, thereby enabling the network device or another device to position the terminal device based on the first and second parameters. For example, the network device may determine the difference between the distances between the terminal device and the access network device at a first and second point in time based on the first and second parameters, and perform positioning based on that distance difference.

[0083] The method for a terminal device to determine a second parameter based on a second TA is the same as the method for determining a first parameter based on a first TA. For example, in step 502, the terminal device determines a first slot corresponding to the first TA, and in step 504, it determines a second slot corresponding to the second TA. Alternatively, in step 502, the terminal device determines a first quantity of milliseconds corresponding to the first TA, and in step 504, it determines a second quantity of milliseconds corresponding to the second TA.

[0084] Optionally, when transmitting a second parameter to a network device, the terminal device may further transmit display information indicating a second time point to the network device, thereby allowing the network device to determine the satellite's location information at the second time point. Since satellites move at high speed and the satellite's location at the first time point differs from its location at the second time point, the terminal device is positioned in subsequent operations based on the satellite's location information at the second time point and the second parameter.

[0085] After the terminal device has sent the first and second parameters to the network device, the network device may perform step 505a or step 505b. Details are as follows.

[0086] Step 505a: The network device positions the terminal device based on the first and second parameters.

[0087] In this implementation, network devices can determine the position of terminal devices.

[0088] For example, a network device may determine a first distance between a terminal device and an access network device at a first time point based on a first parameter and the speed of light, and a second distance between the terminal device and the access network device at a second time point based on a second parameter and the speed of light. The network device draws a circle centered on the location of the access network device at the first time point and using the first distance as the radius, and then draws a circle centered on the location of the access network device at the second time point and using the second distance as the radius, and then estimates the location of the terminal device by using a positioning algorithm such as a trilateral positioning algorithm or a least-squares algorithm.

[0089] As an alternative, the network device may determine, based on a first and second parameter, the difference between the distance between the terminal device and the access network device at a first time point and the distance between the terminal device and the access network device at a second time point, and then estimate the location of the terminal device based on the location of the access network device at the first time point, the location of the access network device at the second time point, and the distance difference.

[0090] Step 505b: The network device sends the first and second parameters to another network device.

[0091] In this implementation, this network device does not position the terminal device, but another network device does. For example, if the network device is the satellite shown in Figure 4a used as a transmission node, the network device does not assume the function of a base station. In this case, the satellite may transmit the received first and second parameters to a ground base station, which then positions the terminal device based on the first and second parameters. Alternatively, the ground base station may transmit the first and second parameters to a network device used for positioning, such as an LMF, which then positions the terminal device based on the first and second parameters. In another example, the satellite is used as a base station, but the base station does not perform the operation to position the terminal device; another network device positions the terminal device. In this case, the satellite may, as an alternative, transmit the first and second parameters to a network device used for positioning.

[0092] Optionally, when transmitting the first and second parameters to another network device, the network device may instead transmit satellite location information at a first time point and satellite location information at a second time point to the other network device, thereby enabling the other network device to position the terminal device based on the satellite location at the first time point, the first parameter, the satellite location at the second time point, and the second parameter. Alternatively, the other network device may obtain the satellite location at the first time point and the satellite location at the second time point through ephemeris-based calculations.

[0093] As described above, the first and second parameters may be in slot units. In this implementation, transmission is performed based on existing signaling formats, with little modification to existing communication standards. However, reporting is performed in slot units, resulting in coarse granularity and making it difficult to accurately represent the corresponding TA. Therefore, to improve positioning accuracy, the following four implementations are provided based on the aforementioned positioning method, thereby allowing network devices to obtain more precise parameters used for positioning.

[0094] Method 1: The difference between the second TA and the first TA can be set to a pre-configured threshold. Specifically, if the terminal device determines that the difference between the TA at the current time and the first TA at the first time point has reached a pre-configured threshold, then the current time point is the second time point, and the terminal device sends a second parameter corresponding to the TA at the second time point to the network device. It should be understood that the ideal case is when the difference between the second TA and the first TA is exactly the pre-configured threshold. In the actual operation process, the difference between the second TA and the first TA only needs to be within the pre-configured range.

[0095] In the aforementioned method, a corresponding trigger condition is set for the terminal device to report the second parameter (specifically, the difference between the TA at the current time and the first TA at the first time point in time reaches a predetermined value). This causes the terminal device to report the first and second parameters that satisfy the predetermined condition, and the network device can then determine a more accurate TA difference based on the first parameter, the second parameter, and the predetermined threshold, thereby improving positioning accuracy. The trigger condition may be configured on the network side or agreed upon in the protocol.

[0096] For example, the pre-set range is [0.5-δ,0.5+δ] or [-0.5-δ,-0.5+δ] (in ms), where δ represents the allowable error value and the subcarrier spacing is assumed to be 15 kHz. If the terminal device determines that the TA at time t1 is 5.6 ms, the terminal device sends display information indicating 6 slots to the network device. The terminal device continuously updates the TA value. If the terminal device determines that the TA has reached 6.1 ms at time t2, since the difference between 6.1 ms and 5.6 ms is within the pre-set range, the terminal device sends a second parameter corresponding to the TA at time t2, in other words, display information indicating 7 slots, to the network device. In this case, the display information received twice by the network device indicates slots 6 and 7, respectively. Based on a pre-configured threshold, the network device determines that the difference between the terminal devices' TAs at time t2 and time t1 is 0.5ms. Based on this accurate TA difference, the network device can either position the terminal device, send the difference between the TAs at time t2 and time t1 to the gateway, or directly forward the information sent by the terminal device to the gateway, which then transmits this information to a device configured to position the terminal device.

[0097] As another example, suppose the pre-configured threshold is 0.5ms and the subcarrier spacing is 15kHz. If the terminal device determines that the TA at time t1 is 4.4ms, the terminal device sends display information indicating 5 slots to the network device. The terminal device continuously updates the TA value. If the terminal device determines that the TA has reached 4.4 + 0.5 = 4.9ms at time t2, the terminal device sends display information indicating 5 slots to the network device. In this case, the display information received twice by the network device indicates 5 slots, but the network device determines, based on the pre-configured threshold, that the difference between the terminal device's TAs at time t2 and time t1 is 0.5ms, and positions the terminal device.

[0098] Method 2: The difference between the current TA and the first TA may be called the TA difference, and the difference between the parameter corresponding to the current TA and the first parameter is called the parameter difference. If the terminal device determines that the difference between the parameter difference and the TA difference at the current time is a pre-set threshold, then the current time is the second time, and the terminal device sends the second parameter corresponding to the TA at the second time to the network device. It should be understood that the case where the difference between the parameter difference and the TA difference is exactly a pre-set threshold is an ideal case. In the actual operation process, the difference between the parameter difference and the TA difference only needs to be within a pre-set range.

[0099] In the aforementioned method, similarly, a corresponding trigger condition is set for the terminal device to report the second parameter (specifically, the difference between the parameter difference and the TA difference at the current time is a pre-set threshold). However, this trigger condition differs from the trigger condition in method 1 in that it causes the terminal device to report the first and second parameters that satisfy the pre-set condition, and the network device can then determine a more accurate TA difference based on the first parameter, the second parameter, and the pre-set threshold, thereby improving positioning accuracy. The trigger condition can be configured on the network side or agreed upon in the protocol.

[0100] For example, suppose the pre-configured threshold is 1 ms, the pre-configured range is ±0.05 ms, and the subcarrier spacing is 15 kHz. If the terminal device determines that the TA at time t1 is 4.4 ms and the corresponding first parameter is 5 slots, the terminal device sends display information indicating 5 slots to the network device. The terminal device continuously updates the TA value. If the terminal device determines that the TA has reached 5.42 ms at time t2, the parameter corresponding to the TA is 6 slots. The TA difference is 5.42 - 4.4 = 1.02 ms, the parameter difference is 1 slot, which is equal to 1 ms, and the difference between the TA difference and the parameter difference is 0.02 ms, which is within the pre-configured range. In this case, the terminal device sends display information indicating the second parameter, in other words, 6 slots, to the network device. In this case, the network device can determine the difference between TAs at time t2 and time t1 based on the difference between parameters at time t2 and time t1, and then position the terminal device.

[0101] Method 3: The difference between the second time point and the first time point is within a predetermined range. The difference between the first time point and the second time point is the travel time of the network device (satellite). Generally, if the travel time of the network device is within a predetermined range, then accordingly, the difference between the second TA and the first TA is also within the required range, thereby enabling the network device or another device to position the terminal device.

[0102] In the aforementioned method, a corresponding trigger condition (specifically, the difference between the current time and the first time is within a pre-defined range) is set for the terminal device to report the second parameter, thereby causing the terminal device to report the first and second parameters that satisfy the pre-defined condition, and enabling the network device to perform high-precision positioning based on the first parameter, the second parameter, and the pre-defined range. The trigger condition may be configured on the network side or agreed upon in the protocol.

[0103] Method 4: After reporting a first parameter corresponding to a first TA, the terminal device may further transmit a first difference between the first parameter and the first TA to a network device, for example by using an Access Layer (NAS) message, thereby transmitting the first difference to the network device, which in turn transmits the first difference to a network device configured to position the terminal device. After reporting a second parameter corresponding to a second TA, the terminal device may further transmit a second difference between the second parameter and the second TA to a network device, for example by using an NAS message, thereby transmitting the second difference to a network device, which in turn transmits the second difference to a network device configured to position the terminal device.

[0104] The terminal device reports first and second parameters based on existing signaling for reporting the TA to the network device. In this manner, the network device can obtain the relevant parameters for positioning the terminal device regardless of whether the network device has completed the positioning procedure for the terminal device in steps 502 and 504. However, for security reasons, the user may anticipate that less secure network devices will not parse the relevant parameters. Therefore, the terminal device may transmit first and second differences separately, which can be used for accurate positioning, so that the network device does not parse the first or second difference and directly forwards the first and second differences to the network device used for positioning.

[0105] For example, assume a subcarrier spacing of 15kHz. The terminal device determines that the TA at time t1 is 4.4ms, the corresponding first parameter is 5 slots, and the first difference is 5-4.4=0.6ms. After reporting 5 slots to the network device, the terminal device sends information about the 0.6ms difference to the network device using a NAS message, which the network device then sends to the LMF. The terminal device determines that the TA at time t2 is 5.6ms, the corresponding second parameter is 6 slots, and the first difference is 6-5.6=0.4ms. After reporting 6 slots to the network device, the terminal device sends information about the 0.4ms difference to the network device using a NAS message, which the network device then sends to the LMF, which can determine the terminal device's TA at time t1 and time t2 and position the terminal device.

[0106] Optionally, the terminal device may send the first and second differences together to the network device, rather than sending them separately each time after determining the differences.

[0107] In the ideal case, it should be understood that the first difference reported by the terminal device is exactly equal to the difference between the first parameter and the first TA, and the second difference is exactly equal to the difference between the second parameter and the second TA. However, in actual operation, the first difference reported by the terminal device and the actual first difference may fall within a predefined range. For example, the predefined range may be [-0.5,0.5], (-0.5,0.5], or [-0.5,0.5], and may be in milliseconds. The second difference reported by the terminal device and the actual second difference may also fall within a predefined range. For example, the terminal device may determine that the precision of the first and second differences is only 0.1 ms, even though the precision of the differences is 0.1 ms when the terminal device transmits the information. In this case, the terminal device is not able to transmit the exact first difference and the exact second difference to the network device.

[0108] In addition, the terminal device may further report the first parameter and the corresponding first difference to the network device. For example, at time 1, TA1 determined by the terminal device is 6.5ms, parameter 1 is 7 slots (corresponding to 7ms), and the first difference is 7-6.5=0.5ms. In this case, the terminal device may report parameter 1 and the first difference, in other words, 7 slots and 0.5ms. At time 2, TA2 determined by the terminal device is 6.3ms, the second parameter is 6 slots (corresponding to 6ms), and the second difference is -0.3ms. In this case, the terminal device may report parameter 2 and the second difference, in other words, 6 slots and -0.3ms.

[0109] Optionally, a terminal device may be configured to report a first parameter and a first difference to the LFM, or to report the first parameter to a network device and the second parameter to the LFM.

[0110] Method 5: The terminal device may transmit the difference between the first TA and the second TA to the network device. For example, assume a subcarrier spacing of 15 kHz. The terminal device determines that at time t1 the first TA is 4.4 ms and the corresponding first parameter is 5 slots, and at time t2 the second TA is 5.6 ms and the corresponding second parameter is 6 slots. In this case, the difference between the first TA and the second TA is 4.4 ms - 5.6 ms = -1.2 ms. In addition to transmitting the first and second parameters to the network device, the terminal device may further transmit the difference of -1.2 ms between the first TA and the second TA (or the difference of 1.2 ms between the second TA and the first TA) to the network device. The network device can then position the terminal device based on the difference between the TAs at time t2 and time t1.

[0111] In an ideal scenario, it should be understood that the difference between the first and second TAs reported by the terminal device may be exactly equal to the actual TA difference. However, in actual operation, the difference between the TA reported by the terminal device and the actual TA difference only needs to be within a pre-defined range.

[0112] In methods 1 to 5, the first and second parameters reported by the terminal device are positioning parameters and must satisfy the conditions in the aforementioned methods. However, parameters reported by the terminal device based on existing procedures and used solely to determine the TA do not need to satisfy the aforementioned conditions. Optionally, in order to distinguish between parameters reported in this embodiment of the present application that are used for positioning and parameters used solely to determine the TA, when reporting the first and second parameters, the terminal device may include in the transmitted message indication that the parameters being reported are parameters used for positioning.

[0113] In the aforementioned embodiments of this application, the terminal device transmits a first parameter corresponding to a first TA at a first time point and a second parameter corresponding to a second TA at a second time point to a network device, thereby enabling the network device, or another network device configured to position the terminal device, to position the terminal device based on the first and second parameters. This method can be applied to satellite communication scenarios to solve the problem of positioning a terminal device when it is possible for the terminal device to be covered by only one satellite. Furthermore, trigger conditions can be set for the terminal device to report the second parameter. In addition, since the accuracy of the TA may be inconsistent with the accuracy of the corresponding parameter, the difference between the corresponding parameter and the TA may be further reported to improve the accuracy of the reported TA and thus improve positioning accuracy.

[0114] In the embodiments described above, an example is used for descriptive purposes in which the terminal device reports a first parameter at a first time point and a second parameter at a second time point. In actual application, the terminal device may report parameters corresponding to more time points to improve the accuracy of positioning the terminal device. For example, a network device may position the terminal device based on parameters reported by the terminal device at four time points. The method for determining the third parameter corresponding to the third TA at the third time point and the fourth parameter corresponding to the fourth TA at the fourth time point is the same as the method for determining the second parameter corresponding to the second TA at the second time point.

[0115] Embodiments of this application further provide a positioning method for solving the problem of positioning terminal devices in satellite communication scenarios or unmanned aerial vehicle communication scenarios. This method is particularly applicable to NGEO satellite communication scenarios.

[0116] A schematic flowchart of the positioning method can be shown in Figure 7, and this positioning method includes the following steps.

[0117] Step 701: The network device broadcasts the first common TA at the first point in time.

[0118] Network devices as used herein may include, but are not limited to, base stations (gNB), access and mobility management function (AMF) network elements, and location management function (LMF) in 5G communication systems, as well as base stations (eNB), transmission points (TP), transmission reception points (TRP), and gateways (GW) in 4G communication systems.

[0119] When this method is applied to the network architecture shown in Figure 4a, Figure 4b, or Figure 4c, satellites (including satellites used as satellite base stations or transmission points) may be used as network devices in the manner shown in Figure 7, gateways may be used as network devices in the manner shown in Figure 7, ground base stations may be used as network devices in the manner shown in Figure 7, or devices in the core network may be used as network devices in the manner shown in Figure 7.

[0120] Network devices can broadcast a common TA to terminal devices. While the common TA does not necessarily have to meet the individual terminal device requirements for transmission delay compensation, it can help terminal devices complete access procedures.

[0121] Step 702: The terminal device sends a first reference signal to the network device based on the first common TA.

[0122] In this embodiment of the present application, even if the terminal device calculates the TA actually required by the terminal device, during positioning, the terminal device still transmits a reference signal to the network device based on a first common TA broadcast by the network device. If the first common TA is not capable of satisfying the terminal device's requirements for compensation of transmission delay, the time when the first reference signal transmitted by the terminal device based on the first common TA actually arrives at the network device, i.e., the time when the network device receives the first reference signal, may differ from the time when the network device expects to receive the first reference signal based on the first common TA, and the difference between these two types of time may be called the residual TA. Specifically, the residual TA generated when the reference signal is transmitted based on the first common TA may be called the first residual TA.

[0123] Step 703: The network device broadcasts the second common TA at the second point in time.

[0124] To facilitate the completion of access procedures for newly accessing terminal devices, network devices may frequently broadcast a common TA. A second common TA broadcast by the network device at a second point in time may be the same as or different from the first common TA.

[0125] Step 704: The terminal device transmits a second reference signal to the network device based on the second common TA.

[0126] As described above, during positioning, the terminal device still transmits a second reference signal to the network device based on a broadcasted second common TA, without considering the TA actually required by the terminal device. Specifically, the time it takes for the second reference signal transmitted by the terminal device based on the second common TA to actually arrive at the network device, i.e., the time it takes for the network device to receive the second reference signal, may differ from the time it expects the network device to receive the second reference signal based on the second common TA, and the difference between these two types of time is called the second residual TA.

[0127] Step 705: The network device determines a first residual TA based on the time it takes to receive a first reference signal, a second residual TA based on the time it takes to receive a second reference signal, and positions the terminal device based on the first and second residual TAs.

[0128] For example, the network device determines the difference between the distance between the terminal device and the network device at a first time point and the distance between the terminal device and the network device at a second time point, based on the first residual TA and the second residual TA. Then, it estimates the location of the terminal device based on the location of the network device at the first time point, the location of the network device at the second time point, and the distance difference.

[0129] The residual time interval (TA), determined by the network device, can be in slot units, milliseconds units, or another time unit.

[0130] The common TA broadcast by a network device may be a feeder TA and a service link common TA, or may include only the service link common TA. The feeder link is the communication link between the satellite and the gateway, and the feeder TA is the TA used when the satellite communicates with the gateway. The service link is the communication link between the satellite and terminal devices, and the service link common TA is the TA used when the terminal devices communicate with the satellite. If the network device is a satellite base station, the common TA may not include a feeder TA, and the terminal devices transmit reference signals only based on the service link common TA.

[0131] Optionally, the network device may transmit the first residual TA and the second residual TA to another device which can be used for positioning, thereby allowing the other device to position the terminal device.

[0132] In the embodiment described above, the terminal device transmits a reference signal to the network device based on a common TA broadcast by the network device. Since there is a residual TA between the common TA broadcast by the network device and the TA actually required by the terminal device, the network device can determine the difference between the distances from the terminal device to the network device at different points in time based on the residual TAs at different points in time, and estimate the location information of the terminal device. This method can be applied to satellite communication scenarios to solve the problem of positioning a terminal device when it is possible for the terminal device to be covered by only one satellite.

[0133] In the embodiments described above, an example is used in which the terminal device reports a first reference signal based on a first common TA and a second reference signal based on a second common TA. In actual application, the terminal device may report further reference signals based on more common TAs, thereby allowing the network device to determine more residual TAs and improve the accuracy of positioning the terminal device. For example, as shown in Figure 8, the satellite base station may broadcast a first common TA at time t1, and the terminal transmits SRS1 based on the first common TA; the satellite base station may broadcast a second common TA at time t2, and the terminal transmits SRS2 based on the second common TA; the satellite base station may broadcast a third common TA at time t3, and the terminal transmits SRS3 based on the third common TA; and the satellite base station may broadcast a fourth common TA at time t4, and the terminal transmits SRS4 based on the fourth common TA. In this case, the satellite base station can determine four residual TAs and position the terminal based on those four residual TAs, or it can transmit the determined residual TAs to a location measurement center, which then positions the terminal.

[0134] In geostationary earth orbit (GEO) satellite communication scenarios, since the satellite is stationary relative to the Earth, the Terminal Arrangement (TA) does not change for terminal devices in a stationary state, and for terminal devices in a moving state, the change in TA may be too small to trigger the reporting procedure. Therefore, the aforementioned method for positioning terminal devices based on parameters corresponding to TA is not applicable to GEO satellite communication scenarios.

[0135] Therefore, embodiments of this application further provide a positioning method. This positioning method can be applied to satellite communication scenarios, geostationary earth orbit (GEO) satellite communication scenarios, or NGEO satellite communication scenarios. In this method, terminal devices are positioned based on the direction of beam direction.

[0136] When carrier frequencies are high, radio signals transmitted at that frequency undergo severe fading during spatial propagation, making it difficult for the receiving end to even detect the signal. Therefore, beamforming (BF) technology is used to obtain a beam with good directivity, increasing power in the transmission direction and improving the signal-to-interference plus noise ratio (SINR) at the receiving end. When the transmitting and receiving ends communicate through a narrow beam, better communication quality is achieved only if the beams used for transmission and reception are aligned in their direction of directivity. Two aligned beams can be called a beam pair. A satellite can communicate with a terminal device in a different direction through beams with different direction of directivity, or a terminal device can communicate with a transceiver node (such as a satellite) in a different direction through beams with different direction of directivity.

[0137] Based on the aforementioned technology, a schematic flowchart of the positioning method can be shown in Figure 9, which includes the following steps.

[0138] Step 901a: The terminal device sends a first message to the network device through the first beam.

[0139] Step 901b: The network device receives the first message through the second beam.

[0140] Network devices as used herein may include, but are not limited to, base stations (gNB), access and mobility management function (AMF) network elements, and location management function (LMF) in 5G communication systems, as well as base stations (eNB), transmission points (TP), transmission reception points (TRP), and gateways (GW) in 4G communication systems.

[0141] When this method is applied to the network architecture shown in Figure 4a, Figure 4b, or Figure 4c, a satellite (including a satellite used as a satellite base station or transmission point) may be used as a network device in the manner shown in Figure 9, or another ground device may be used as a network device in the manner shown in Figure 9. When the network device is a ground device, the satellite reflects information received through a separate beam, thereby allowing the ground network device to receive that information through a separate beam.

[0142] The first beam of a terminal device and the second beam of a network device can form a beam pair. Specifically, the network device can receive messages transmitted by the terminal device through the first beam via the second beam, and the terminal device can receive messages transmitted by the network device through the second beam via the first beam. For ease of distinction, the first beam of the terminal device and the second beam of the network device may be referred to as beam pair 1.

[0143] Step 902a: The terminal device sends a second message to the network device through the third beam.

[0144] Step 902b: The network device receives the second message through the fourth beam.

[0145] To ensure communication quality, there is an overlap in the spatial range covered by beams with distinct directional orientations, thereby allowing network devices and terminal devices to communicate with each other through beam pair 1 or beam pair 2.

[0146] The third beam of the terminal device and the fourth beam of the network device can form a beam pair. Specifically, the network device can receive messages transmitted by the terminal device through the third beam via the fourth beam, and the terminal device can receive messages transmitted by the network device through the fourth beam via the third beam. For ease of distinction, the third beam of the terminal device and the fourth beam of the network device may be called beam pair 2.

[0147] Step 903: The network device positions the terminal device based on the direction of the second beam and the direction of the fourth beam.

[0148] After receiving a message transmitted by a terminal device through the second and fourth beams, the network device can determine that the terminal device is located in an area covered by both the second and fourth beams and then position the terminal device.

[0149] To help network devices identify the beams through which received information is transmitted, separate time-frequency resources may be assigned to messages transmitted through separate beam pairs. Specifically, a network device may assign separate time-frequency resources to reference signals transmitted through separate beam pairs and notify terminal devices of the assigned time-frequency resources. For example, beam a from a network device and beam a' from a terminal device may form beam pair A, and beam b from a network device and beam b' from a terminal device may form beam pair B. The network device assigns time-frequency resource 1 to a sounding reference signal (SRS) transmitted through beam pair A and time-frequency resource 2 to an SRS transmitted through beam pair B. In this case, when receiving an SRS, the network device may determine the beams through which the SRS is received based on the time-frequency resources available for receiving the SRS.

[0150] Alternatively, a network device may configure separate scrambling / descrambling schemes for information transmitted through separate beam pairs. The network device configures scrambling / descrambling scheme 1 for beam pair 1 and scrambling / descrambling scheme 2 for beam pair 2. In this case, scheme 1 is used for scrambling when a terminal device sends a message to the network device through the beams in beam pair 1, and scheme 2 is used for scrambling when the terminal device sends a message to the network device through the beams in beam pair 2. Upon receiving a message, the network device may determine, based on the descrambling scheme, which beam the incoming message traversed.

[0151] Alternatively, separate polarization schemes may be configured for separate beam pairs. For example, network devices and terminal devices may use a vertical polarization scheme for beam pair 1 and a horizontal polarization scheme for beam pair 2.

[0152] Alternatively, a network device may configure separate common TAs for separate beam pairs (these may be feeder TAs and service link common TAs, or service link common TAs only). When sending a message to a network device through separate beams, the terminal device sends the message based on the common TA corresponding to the beam pair providing the service to the terminal device, thereby generating separate residual TAs for the separate beam pairs. In this case, the network device may determine the beam through which an incoming message is received based on the separate residual TAs.

[0153] In another possible implementation, after receiving information transmitted by the network device through the second beam, the terminal device may perform step 901a. In this case, the first message transmitted by the terminal device may include the identifier of the second beam or the identifier of beam pair 1. Correspondingly, after receiving information transmitted by the network device through the fourth beam, the terminal device may perform step 902a. In this case, the second message transmitted by the terminal device may include the identifier of the fourth beam or the identifier of beam pair 2.

[0154] In the embodiments described above, the terminal device transmits a message to the network device through a separate beam, thereby allowing the network device to determine the orientation of the terminal device based on the direction of the beam for reception. This method can be applied to satellite communication scenarios, particularly GEO scenarios, to solve the problem that terminal devices cannot be positioned based on TA due to the satellite being stationary relative to the ground. Furthermore, separate configuration parameters such as time-frequency resources, scrambling / descrambling scheme, polarization scheme, and common TA can be configured for the separate beam, thereby allowing the network device to determine the beam for receiving the message transmitted by the terminal device.

[0155] In the embodiments described above, an example is used in which the network device communicates with the terminal device through two beam pairs. In actual application, more beam pairs may be used to improve the accuracy of positioning the terminal device. For example, as shown in Figure 10, the network device configures a common TA1 for the terminal device through beam 1, a common TA2 for the terminal device through beam 2, and a common TA3 for the terminal device through beam 3. Since the terminal device is located in an area jointly covered by the three beams, the terminal device can accordingly transmit a reference signal to the network device through the three beams. In this case, after receiving the reference signal transmitted by the terminal device through beam 1, beam 2, and beam 3, respectively, the network device can determine that the terminal device is located in an area jointly covered by the three beams. In this way, the terminal device is positioned more accurately.

[0156] Figure 11 is a diagram of a communication device according to an embodiment of the present application. This communication device includes a processing module 1101 and a transceiver module 1102. The processing module 1101 is configured to perform data processing to be performed by this communication device. The transceiver module 1102 is configured to perform information reception and transmission processing as described in the method embodiment above. It should be understood that the processing module 1101 in this embodiment of the present application may be implemented by a processor or processor-related circuit components (or referred to as a processing circuit), and the transceiver module 1102 may be implemented by a receiver, receiver-related circuit components, transmitter, or transmitter-related circuit components.

[0157] For example, this communication device may be a communication device, a chip used in that communication device, or another combination of devices or components having the functionality of that communication device.

[0158] When this communication device implements the embodiment shown in Figure 5 as a terminal device, the processing module 1101 is configured to determine a first timing advance TA between the terminal device and the access network device at a first time point. The transceiver module 1102 is configured to transmit a first parameter corresponding to the first TA to the network device. The processing module 1101 is further configured to determine a second TA between the terminal device and the access network device at a second time point. The transceiver module 1102 is further configured to transmit a second parameter corresponding to the second TA to the network device, thereby allowing the network device to position the terminal device based on the first and second parameters, or for the network device to transmit the first and second parameters to another network device.

[0159] In addition, the aforementioned module may be further configured to support other processes executed by the terminal device in the embodiment shown in Figure 5 and any implementation of that embodiment. For beneficial effects, please refer to the above description; further details will not be described here again.

[0160] When this communication device implements the embodiment shown in Figure 5 as a network device, the transceiver module 1102 receives a first parameter transmitted by the terminal device, the first parameter being a parameter corresponding to a first timing advance TA between the terminal device and the access network device at a first time point, and receives a second parameter transmitted by the terminal device, the second parameter being a parameter corresponding to a second TA between the terminal device and the access network device at a second time point. The processing module 1101 is configured to position the terminal device based on the first and second parameters. Alternatively, the transceiver module 1102 transmits the first and second parameters to another network device, thereby allowing the other network device to position the terminal device based on the first and second slots, or the other network device transmits the first and second parameters to a network device configured to position the terminal device.

[0161] In addition, the aforementioned module may be further configured to support other processes executed by the network device in the embodiment shown in Figure 5 and any implementation of that embodiment. For beneficial effects, please refer to the above description; further details will not be described again here.

[0162] When this communication device implements the embodiment shown in Figure 7 as a terminal device, the transceiver module 1102 is configured to receive a first common timing advance TA broadcast by the network device and, under the control of the processing module 1101, transmit a first reference signal to the network device based on the first common TA. The transceiver module 1102 is further configured to receive a second common TA broadcast by the network device and, under the control of the processing module 1101, transmit a second reference signal to the network device based on the second common TA, thereby allowing the network device to position the terminal device based on the actual reception time of the first reference signal, the time determined based on the first common TA, the actual reception time of the second reference signal, and the time determined based on the second common TA.

[0163] In addition, the aforementioned module may be further configured to support other processes executed by the terminal device in the embodiment shown in Figure 7 and any implementation of that embodiment. For beneficial effects, please refer to the above description; further details will not be described again here.

[0164] When this communication device implements the embodiment shown in Figure 7 as a network device, the transceiver module 1102 is configured to broadcast a first common timing advance TA, receive a first reference signal transmitted by a terminal device based on the first common TA, broadcast a second common TA, and receive a second reference signal transmitted by a terminal device based on the second common TA. The processing module 1101 is configured to position the terminal device based on the actual reception time of the first reference signal, a time determined based on the first common TA, the actual reception time of the second reference signal, and a time determined based on the second common TA.

[0165] In addition, the aforementioned module may be further configured to support other processes executed by the network device in the embodiment shown in Figure 7 and any implementation of that embodiment. For beneficial effects, please refer to the above description; further details will not be described again here.

[0166] When this communication device implements the embodiment shown in Figure 9 as a terminal device, the transceiver module 1102, under the control of the processing module 1101, transmits a first message to the network device through a first beam and a second message to the network device through a second beam, thereby allowing the network device to position the terminal device based on the direction of the beam for receiving the first message and the direction of the beam for receiving the second message.

[0167] In addition, the aforementioned module may be further configured to support other processes executed by the terminal device in the embodiment shown in Figure 9 and any implementation of that embodiment. For beneficial effects, please refer to the above description; further details will not be described again here.

[0168] When this communication device implements the embodiment shown in Figure 9 as a network device, the transceiver module 1102 is configured to receive a first message transmitted by a terminal device through a first beam and a second message transmitted by a terminal device through a second beam. The processing module 1101 is configured to position the terminal device based on the direction of the first beam and the direction of the second beam.

[0169] In addition, the aforementioned module may be further configured to support other processes executed by the network device in the embodiment shown in Figure 9 and any implementation of that embodiment. For beneficial effects, please refer to the above description; further details will not be described again here.

[0170] Based on the same technical concept, embodiments of this application further provide a communication device, which includes a processor 1201 shown in Figure 12 and a communication interface 1202 connected to the processor 1201.

[0171] The processor 1201 may be a general-purpose processor, a microprocessor, an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), or another programmable logic device, discrete gate or transistor logic device, or one or more integrated circuits configured to control the programmed execution of the solution in this application. The general-purpose processor may be a microprocessor, any conventional processor, etc. The steps of the method disclosed in connection with embodiments of this application may be performed and completed directly by using a hardware processor, or by using a combination of hardware modules and software modules in that processor.

[0172] The communication interface 1202 communicates with another device or a communication network such as a RAN using any transceiver-type device.

[0173] In this embodiment of the present application, the processor 1201 is configured to invoke the communication interface 1202 to perform receiving and / or transmitting functions and to perform a positioning method according to any one of the possible implementations described above.

[0174] Furthermore, this communication device may include a memory 1203 and a communication bus 1204.

[0175] Memory 1203 is configured to store program instructions and / or data, thereby allowing the processor 1201 to invoke the instructions and / or data stored in memory 1203 to perform the aforementioned functions of the processor 1201. Memory 1203 may be, but is not limited to, read-only memory (ROM) or another type of static storage device capable of storing static information and instructions, random access memory (RAM) or another type of dynamic storage device capable of storing information and instructions, or electrically erasable programmable read-only memory (EEPROM) or any other media accessible by a computer, which may be used to carry or store expected program code in the form of instructions or data structures. Memory 1203 may exist independently, for example, as off-chip memory and connected to the processor 1201 via the communication bus 1204. Alternatively, memory 1203 may be integrated with the processor 1201.

[0176] The communication bus 1204 may include paths for transmitting information between the aforementioned components.

[0177] For example, this communication device may be a terminal device in the aforementioned method embodiment, or it may be a network device in the aforementioned method embodiment.

[0178] The processor 1201 is configured to perform data processing operations for this communication device. The communication interface 1202 is configured to perform receiving and transmitting operations for this communication device.

[0179] When this communication device implements the embodiment shown in Figure 5 as a terminal device, the processor 1201 is configured to perform, through the communication interface 1202, an operation to determine a first timing advance TA between the terminal device and the access network device at a first time point, an operation to send a first parameter corresponding to the first TA to the network device, an operation to determine a second TA between the terminal device and the access network device at a second time point, and an operation to send a second parameter corresponding to the second TA to the network device, thereby allowing the network device to position the terminal device based on the first and second parameters, or for the network device to send the first and second parameters to another network device.

[0180] In addition, the aforementioned module may be further configured to support other processes executed by the terminal device in the embodiment shown in Figure 5 and any implementation of that embodiment. For beneficial effects, please refer to the above description; further details will not be described here again.

[0181] When this communication device implements the embodiment shown in Figure 5 as a network device, the processor 1201 is configured to perform, through the communication interface 1202, an operation to receive a first parameter transmitted by a terminal device, wherein the first parameter is a parameter corresponding to a first timing advance TA between the terminal device and the access network device at a first time point; an operation to receive a second parameter transmitted by the terminal device, wherein the second parameter is a parameter corresponding to a second TA between the terminal device and the access network device at a second time point; and an operation to position the terminal device based on the first and second parameters, or to transmit the first and second parameters to another network device, thereby allowing the other network device to position the terminal device based on a first and second slot, or for the other network device to transmit the first and second parameters to a network device configured to position the terminal device.

[0182] In addition, the aforementioned module may be further configured to support other processes executed by the network device in the embodiment shown in Figure 5 and any implementation of that embodiment. For beneficial effects, please refer to the above description; further details will not be described again here.

[0183] When this communication device implements the embodiment shown in Figure 7 as a terminal device, the processor 1201 is configured to perform, through the communication interface 1202, operations to receive a first common timing advance TA broadcast by the network device, to transmit a first reference signal to the network device based on the first common TA, to receive a second common TA broadcast by the network device, and to transmit a second reference signal to the network device based on the second common TA, thereby causing the network device to position the terminal device based on the actual reception time of the first reference signal, the time determined based on the first common TA, the actual reception time of the second reference signal, and the time determined based on the second common TA.

[0184] In addition, the aforementioned module may be further configured to support other processes executed by the terminal device in the embodiment shown in Figure 7 and any implementation of that embodiment. For beneficial effects, please refer to the above description; further details will not be described again here.

[0185] When this communication device implements the embodiment shown in Figure 7 as a network device, the processor 1201 is configured to perform the following operations via the communication interface 1202: broadcasting a first common timing advance TA; receiving a first reference signal transmitted by a terminal device based on the first common TA; broadcasting a second common TA; receiving a second reference signal transmitted by a terminal device based on the second common TA; and positioning the terminal device based on the actual reception time of the first reference signal, a time determined based on the first common TA, the actual reception time of the second reference signal, and a time determined based on the second common TA.

[0186] In addition, the aforementioned module may be further configured to support other processes executed by the network device in the embodiment shown in Figure 7 and any implementation of that embodiment. For beneficial effects, please refer to the above description; further details will not be described again here.

[0187] When this communication device implements the embodiment shown in Figure 9 as a terminal device, the processor 1201 is configured to perform, through the communication interface 1202, operations to transmit a first message to a network device through a first beam, and to transmit a second message to the network device through a second beam, thereby causing the network device to position the terminal device based on the direction of the beam for receiving the first message and the direction of the beam for receiving the second message.

[0188] In addition, the aforementioned module may be further configured to support other processes executed by the terminal device in the embodiment shown in Figure 9 and any implementation of that embodiment. For beneficial effects, please refer to the above description; further details will not be described again here.

[0189] When this communication device implements the embodiment shown in Figure 9 as a network device, the processor 1201 is configured to perform, through the communication interface 1202, the operations of receiving a first message transmitted by a terminal device through a first beam, receiving a second message transmitted by a terminal device through a second beam, and positioning the terminal device based on the direction of the first beam and the direction of the second beam.

[0190] In addition, the aforementioned module may be further configured to support other processes executed by the network device in the embodiment shown in Figure 9 and any implementation of that embodiment. For beneficial effects, please refer to the above description; further details will not be described again here.

[0191] Based on the same technical concept, embodiments of this application further provide a computer-readable storage medium that stores computer-readable instructions. When these computer-readable instructions are executed on a computer, a positioning method is performed according to one of the possible implementations described above.

[0192] Embodiments of this application provide a computer program product including instructions. When this computer program product is run on a computer, the aforementioned method embodiments are made possible to be executed.

[0193] In the description of the embodiments of this application, the term "and / or" describes the relationship between the related objects and indicates that three relationships may exist. For example, "A and / or B" may refer to three cases: "only A exists," "both A and B exist," and "only B exists." In this application, "multiple" means two or more.

[0194] In addition, it should be understood that in the description of this application, terms such as “first,” “second,” and “third” are intended solely for the purpose of distinguishing them for descriptive purposes and should not be understood as indicating or implying relative importance or sequence. References to “embodiments,” “several embodiments,” etc., described herein mean that one or more embodiments of this application include certain features, structures, or characteristics described in relation to the embodiments. Therefore, statements appearing in various places herein, such as “in an embodiment,” “in some embodiments,” “in some other embodiments,” and “in other embodiments,” do not necessarily mean that they refer to the same embodiment. Instead, those statements mean “one or more of the embodiments, but not all of them,” unless otherwise specifically emphasized. The terms “comprise,” “include,” and “have,” and their variations, all mean “include, but not limited to,” unless otherwise specifically emphasized.

[0195] Embodiments of this application provide a computer-readable storage medium for storing a computer program, the computer program including instructions for performing the method embodiments described above.

[0196] Embodiments of this application provide a computer program product including instructions. When this computer program product is run on a computer, the computer is enabled to perform the method embodiments described above.

[0197] Those skilled in the art will understand that embodiments of this application may be provided as methods, systems, or computer program products. Therefore, this application may take the form of hardware-only embodiments, software-only embodiments, or embodiments combining software and hardware. In addition, this application may take the form of a computer program product implemented on one or more computer-usable storage media (including, but not limited to, magnetic disk storage, CD-ROMs, optical memory, etc.) containing computer-usable program code.

[0198] This application is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of this application. It should be understood that computer program instructions may be used to implement each process and / or each block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams. These computer program instructions may be provided to a processor in a general-purpose computer, a dedicated computer, an embedded processor, or another programmable data processing device to create a machine, thereby generating a device for performing a specific function in one or more processes in the flowchart and / or one or more blocks in the block diagram.

[0199] These computer program instructions may, alternatively, be stored in computer-readable memory that can instruct a computer or another programmable data processing device to operate in a specific manner, thereby producing an output that includes an instruction unit. This instruction unit performs a specific function in one or more processes in a flowchart and / or one or more blocks in a block diagram.

[0200] These computer program instructions can, alternatively, be loaded onto a computer or another programmable data processing device, thereby executing a series of operations and steps on that computer or other programmable device to produce computer-executed processing. Thus, these instructions executed on that computer or other programmable device provide steps for performing a specific function in one or more processes in a flowchart and / or one or more blocks in a block diagram.

[0201] While preferred embodiments of this application have been described, those skilled in the art will be able to make further changes and modifications to these embodiments once the inventive basic concept is understood. Therefore, the following claims are intended to be interpreted as covering both the preferred embodiments and all changes and modifications that fall within the scope of this application.

[0202] It will be apparent to those skilled in the art that various modifications and variations can be made to the embodiments of this application without departing from the scope of the embodiments. In this manner, this application is intended to cover such modifications and variations to the embodiments of this application, insofar as they fall within the scope of the claims below and their equivalent technologies in this application.

Claims

1. A positioning method, A first communication device determines a first timing advance (TA) between the first communication device and the access network device at a first point in time; The first communication device transmits a first parameter corresponding to the first TA to a network device, The first communication device determines a second TA between the first communication device and the access network device at a second time point in time; The first communication device transmits a second parameter corresponding to the second TA to the network device, thereby the network device positions the first communication device based on the first parameter and the second parameter. Includes, The access network device is either a non-geostationary Earth orbit (NGEO) satellite used as a base station, or The aforementioned access network device is either an unmanned aerial vehicle (UAV) used as a base station, or The access network device is a ground base station connected to the first communication device via a gateway and a third communication device, the third communication device is an NGEO or UAV, the third communication device is connected to the gateway via an air interface, and the gateway is connected to the base station via a wireless or wired link. The first parameter is the first TA, the second parameter is the second TA, or The first parameter is obtained by rounding the first TA, and the second parameter is obtained by rounding the second TA, or A method wherein the first parameter is the number of first slots corresponding to the first TA, and the second parameter is the number of second slots corresponding to the second TA.

2. The method according to claim 1, wherein the first communication device transmits a second parameter corresponding to the second TA to the network device, which further causes the network device to transmit the first parameter and the second parameter to another network device.

3. The difference between the second TA and the first TA is within a predetermined range. The method according to claim 1.

4. The method according to claim 1, wherein the difference between the second TA and the first TA and the difference between the second parameter and the first parameter are within a preset range.

5. The first communication device transmits a first difference between the first parameter and the first TA and a second difference between the second parameter and the second TA to the network device, wherein the difference between the transmitted first difference and the actual difference between the first parameter and the first TA is within a preset range, and the difference between the transmitted second difference and the actual difference between the second parameter and the second TA is within the preset range, thereby allowing the network device to position the first communication device based on the first parameter, the first difference, the second parameter, and the second difference, or the network device transmits the first parameter, the first difference, the second parameter, and the second difference to another network device, or The first communication device transmits the TA difference to the network device, wherein the difference between the TA difference and the difference between the first TA and the second TA is within a preset range, and the network device then positions the first communication device based on the first parameter, the second parameter, and the TA difference, or the network device transmits the first parameter, the second parameter, and the TA difference to another network device. The method according to claim 1, further comprising:

6. A positioning method, A second communication device receives a first parameter transmitted by a terminal device, wherein the first parameter is a parameter corresponding to a first timing advance (TA) between the terminal device and the access network device at a first time point in time. The steps include: receiving a second parameter transmitted by the terminal device using the second communication device, wherein the second parameter is a parameter corresponding to a second TA between the terminal device and the access network device at a second time point in time; The second communication device positions the terminal device based on the first and second parameters, or transmits the first and second parameters to another network device, thereby allowing the other network device to position the terminal device based on the first and second parameters, or transmits the first and second parameters to a network device configured to position the terminal device. Includes, The access network device is either a non-geostationary Earth orbit (NGEO) satellite used as a base station, or The aforementioned access network device is either an unmanned aerial vehicle (UAV) used as a base station, or The access network device is a ground base station connected to the terminal device via a gateway and a third communication device, the third communication device is an NGEO or UAV, the third communication device is connected to the gateway via an air interface, and the gateway is connected to the base station via a wireless or wired link. The first parameter is the first TA, the second parameter is the second TA, or The first parameter is obtained by rounding the first TA, and the second parameter is obtained by rounding the second TA, or A method wherein the first parameter is the number of first slots corresponding to the first TA, and the second parameter is the number of second slots corresponding to the second TA.

7. The method according to claim 6, wherein the difference between the second TA and the first TA is a pre-set threshold.

8. The method according to claim 6, wherein the difference between the second TA and the first TA and the difference between the second parameter and the first parameter are within a preset range.

9. The aforementioned method, The second communication device receives a first difference between the first parameter and the first TA transmitted by the terminal device and a second difference between the second parameter and the second TA, wherein the difference between the received first difference and the actual difference between the first parameter and the first TA is within a preset range, and the difference between the received second difference and the actual difference between the second parameter and the second TA is within the preset range. It further includes, The step of positioning the terminal device based on the first and second parameters using the second communication device is: The second communication device determines the first TA based on the first difference and the first parameter, the second communication device determines the second TA based on the second difference and the second parameter, and the second communication device positions the terminal device based on the first TA and the second TA. Includes, or The method according to claim 6, further comprising the step of transmitting the first difference and the second difference to the other network device by the second communication device.

10. The aforementioned method, A step of receiving the TA difference transmitted by the terminal device using the second communication device, wherein the difference between the TA difference and the difference between the first TA and the second TA is within a preset range. It further includes, The step of positioning the terminal device based on the first and second parameters using the second communication device is: The second communication device positions the terminal device based on the first parameter, the second parameter, and the TA difference. Includes, or The method according to claim 6, further comprising the step of transmitting the TA difference to the other network device by the second communication device.

11. A communication device comprising a processor, memory and a communication interface separately coupled to the processor, wherein the communication interface is configured to communicate with another device, and the processor is configured to execute instructions or programs in the memory and to execute the method according to any one of claims 1 to 10 through the communication interface.

12. A computer-readable storage medium that stores instructions, and when the instructions are executed by a computer, the computer is able to perform the method according to any one of claims 1 to 10.

13. A communication system comprising a terminal device and a network device, wherein the terminal device is configured to perform the method described in any one of claims 1 to 5, and the network device is configured to perform the method described in any one of claims 6 to 10.

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