Communication method and device

Abstract

The embodiment of the invention provides a communication method and device. The method is executed by a terminal device or a chip applied to the terminal device, and the method comprises: receiving a first system message from a network device, the first system message comprising a first condition for the terminal device to determine whether to receive and / or read a second system message, the second system message comprising ephemeris information configured by the network device; determining whether the first condition is met or not; and under the condition that the first condition is met, receiving and / or reading the second system message. In the embodiment of the invention, the terminal equipment can receive and / or read the second system message only when the first condition is met, that is, the terminal equipment can receive and / or read the ephemeris information only when the first condition is met, so that invalid reading of the ephemeris information is reduced, and the measurement power consumption of the terminal equipment is reduced.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a communication method and device. Background Art

[0002] For the scenario where the terminal device reselects from a terrestrial network (TN) cell to a non-terrestrial network (NTN) cell, the terminal device needs to perform neighbor measurement on the NTN cell (i.e., NTN neighbor measurement). In order to improve the cell reselection efficiency of the terminal device, the TN broadcasts ephemeris information to assist the terminal device in performing neighbor measurement on the NTN cell.

[0003] Currently, after the TN broadcasts the ephemeris information, the terminal device will always maintain the ephemeris information, that is, the terminal device will continue to receive and read system messages to update the ephemeris information, resulting in a large measurement power consumption of the terminal device. Summary of the invention

[0004] The embodiments of the present application provide a communication method and apparatus for reducing the measurement power consumption of a terminal device.

[0005] In a first aspect, an embodiment of the present application provides a communication method, which can be executed by a terminal device or by a chip system, and the chip system can realize the functions of the terminal device. The method includes: receiving a first system message from a network device, the first system message includes a first condition, the first condition is used by the terminal device to determine whether to receive and / or read a second system message, the second system message includes ephemeris information configured by the network device; determining whether the first condition is met; and receiving and / or reading the second system message if the first condition is met.

[0006] In an embodiment of the present application, the terminal device can receive and / or read the second system message only when the first condition is met, that is, the terminal device can receive and / or read the ephemeris information only when the first condition is met, thereby reducing the invalid reading of the ephemeris information and reducing the measurement power consumption of the terminal device.

[0007] In an optional embodiment, the first condition includes one or more of the following: the signal quality of the service cell of the terminal device is lower than or equal to the first threshold; the TN neighbor measurement condition is met; the TN neighbor measurement is performed; the signal quality of the TN neighbor of the service cell of the terminal device is lower than or equal to the second threshold; or, the priority of the NTN neighbor of the service cell of the terminal device is higher than the priority of the service cell. In this embodiment, since the terminal device reads the ephemeris information in order to perform NTN neighbor measurement, if the terminal device does not need to perform NTN neighbor measurement, then the terminal device does not need to read the ephemeris information. Therefore, the first condition can be used to limit the terminal device from reading the ephemeris information, thereby reducing invalid reading of ephemeris information and reducing the measurement power consumption of the terminal device.

[0008] In an optional implementation, if the signal quality of the TN neighboring area of ​​the service cell of the terminal device is lower than or equal to the second threshold, the priority of the TN neighboring area is higher than the priority of the NTN neighboring area of ​​the service cell. In this implementation, since the priority of NTN is lower than the priority of TN, the terminal device does not need to perform NTN neighboring area measurement when there is TN coverage around the terminal device. Therefore, the terminal device can read the second system message only when all TN neighboring areas with a priority higher than the NTN neighboring area have performed neighboring area measurement and the measured signal quality is lower than or equal to the second threshold, thereby reducing the invalid reading of ephemeris information and reducing the measurement power consumption of the terminal device.

[0009] In an optional embodiment, the first system message also includes a second condition; the method further includes: performing NTN neighbor cell measurement when the second condition is met, and the second condition includes that the signal quality of the TN neighbor cell of the service cell of the terminal device is lower than or equal to the second threshold. In this embodiment, since the priority of NTN is lower than the priority of TN, the terminal device does not need to perform NTN neighbor cell measurement when there is TN coverage around the terminal device, so the terminal device can perform NTN neighbor cell measurement only when the signal quality of the TN neighbor cell is lower than or equal to the second threshold, which enhances the NTN neighbor cell measurement conditions, reduces invalid measurements of the NTN neighbor cell, and reduces the measurement power consumption of the terminal device.

[0010] In an optional implementation, the priority of the TN neighboring area is higher than the priority of the NTN neighboring area of ​​the service cell. In this implementation, since the priority of NTN is lower than that of TN, the terminal device does not need to perform NTN neighboring area measurement when there is TN coverage around the terminal device. Therefore, the terminal device can perform NTN neighboring area measurement only when all TN neighboring areas with a higher priority than the NTN neighboring area have performed neighboring area measurement and the measured signal quality is lower than or equal to the second threshold, thereby enhancing the NTN neighboring area measurement conditions, reducing invalid measurements of NTN neighboring areas, and reducing the measurement power consumption of the terminal device.

[0011] In an optional implementation, the method further includes: when the first condition is not met and the second condition is met, receiving and / or reading the second system message before performing NTN neighbor measurement. In this implementation, since the terminal device reads the ephemeris information in order to perform NTN neighbor measurement, if the terminal device does not need to perform NTN neighbor measurement, then the terminal device does not need to read the ephemeris information, so the terminal device can read the second system message before performing NTN neighbor measurement, that is, the ephemeris information is read before performing NTN neighbor measurement, thereby reducing invalid reading of ephemeris information and reducing the measurement power consumption of the terminal device.

[0012] In an optional implementation, the method further includes: when the first condition is not met and the first system message also includes first indication information, receiving and / or reading the second system message, the first indication information being used to indicate that the second system message includes the ephemeris information. In this implementation, the terminal device can read the second system message when the first system message indicates that the second system message includes the ephemeris information, thereby reducing invalid reading of the ephemeris information and thus reducing the measurement power consumption of the terminal device.

[0013] In an optional implementation, the first threshold is equal to the third threshold, and the third threshold is a threshold corresponding to the TN neighboring cell measurement condition. In this implementation, the first threshold can directly reuse the threshold corresponding to the TN neighboring cell measurement condition, and since the threshold corresponding to the TN neighboring cell measurement condition complies with the provisions of the existing protocol, the compatibility is better.

[0014] In an optional implementation, the second threshold is higher than or equal to the third threshold, and the third threshold is the threshold corresponding to the TN neighbor measurement condition. In this implementation, the second threshold can directly reuse the threshold corresponding to the TN neighbor measurement condition. Since the threshold corresponding to the TN neighbor measurement condition complies with the provisions of the existing protocol, the compatibility is better. Alternatively, the second threshold can be higher than the threshold corresponding to the TN neighbor measurement condition, and the threshold corresponding to the TN neighbor measurement condition is the same as the threshold corresponding to the unenhanced NTN neighbor measurement condition, so that the terminal device ephemeris information reading condition is easier to achieve than the unenhanced NTN neighbor measurement condition, so that the terminal device can read the ephemeris information before performing the NTN neighbor measurement, and then can use the ephemeris information to perform the NTN neighbor measurement.

[0015] In a second aspect, an embodiment of the present application further provides a switching method, which can be executed by a network device, or by a chip system, which can implement the functions of the network device. The method includes: broadcasting a first system message and a second system message, wherein the first system message includes a first condition, and the first condition is used by the terminal device to determine whether to receive and / or read the second system message, and the second system message includes the ephemeris information configured by the network device.

[0016] In an optional embodiment, the first condition includes one or more of the following: the signal quality of the service cell of the terminal device is lower than or equal to a first threshold; the TN neighbor cell measurement condition is met; TN neighbor cell measurement is performed; the signal quality of the TN neighbor cell of the service cell of the terminal device is lower than or equal to a second threshold; or, the priority of the NTN neighbor cell of the service cell of the terminal device is higher than the priority of the service cell.

[0017] In an optional implementation, if the signal quality of the TN neighboring cell of the serving cell of the terminal device is lower than or equal to the second threshold, the priority of the TN neighboring cell is higher than the priority of the NTN neighboring cell of the serving cell.

[0018] In an optional implementation, the first system message further includes a second condition, where the second condition is used by the terminal device to perform NTN neighbor cell measurement, and the second condition includes that the signal quality of the TN neighbor cell of the service cell of the terminal device is lower than or equal to a second threshold.

[0019] In an optional implementation, the priority of the TN neighboring cell is higher than the priority of the NTN neighboring cell of the serving cell.

[0020] In an optional implementation, the first threshold is equal to the third threshold, and the third threshold is a threshold corresponding to the TN neighboring cell measurement condition.

[0021] In an optional implementation, the second threshold is higher than or equal to a third threshold, and the third threshold is a threshold corresponding to a TN neighboring cell measurement condition.

[0022] Regarding the technical effects brought about by the second aspect or some optional implementation methods, reference may be made to the introduction to the technical effects of the first aspect or corresponding implementation methods.

[0023] In a third aspect, an embodiment of the present application provides a communication device, including a processor and a memory; the memory is used to store computer instructions, and when the device is running, the processor executes the computer instructions stored in the memory to enable the device to execute any implementation method in the first to second aspects above. The memory can be a volatile or non-volatile memory, such as a cache in a semiconductor chip.

[0024] In a fourth aspect, an embodiment of the present application provides a communication device, which may be a terminal device or a network device, or a chip for a terminal device or a network device. The device has the function of implementing any implementation method of the first aspect to the second aspect above. The function may be implemented by hardware, or by hardware executing corresponding software implementation. The hardware or software includes one or more modules corresponding to the above functions.

[0025] In a fifth aspect, an embodiment of the present application provides a communication device, comprising a unit or means for executing each step of any implementation method in the first to second aspects above.

[0026] In a sixth aspect, an embodiment of the present application provides a communication device, including a processor and an interface circuit, wherein the processor is used to communicate with other devices through the interface circuit and execute any implementation method in the first to second aspects above. The processor may be one or more processors.

[0027] In a seventh aspect, an embodiment of the present application provides a communication device, comprising a processor coupled to a memory, the processor being used to call a program stored in the memory to execute any implementation method in the first to second aspects above. The memory may be located inside the device or outside the device. The processor may also be one or more processors.

[0028] In an eighth aspect, an embodiment of the present application further provides a computer-readable storage medium, wherein instructions are stored in the computer-readable storage medium, and when the computer-readable storage medium is run on a communication device, any implementation method in the above-mentioned first to second aspects is executed.

[0029] In the ninth aspect, an embodiment of the present application further provides a computer program product, which includes a computer program or instructions. When the computer program or instructions are executed by a communication device, any implementation method in the above-mentioned first to second aspects is executed.

[0030] In the tenth aspect, an embodiment of the present application also provides a chip system, including: a processor, used to execute any implementation method in the above-mentioned first aspect to the second aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A schematic diagram of an NTN system provided in an embodiment of the present application;

[0032] Figure 2 A schematic diagram of another NTN system provided in an embodiment of the present application;

[0033] Figure 3 A schematic diagram of the structure of an access network device provided in an embodiment of the present application;

[0034] Figure 4 A flow chart of a communication method provided in an embodiment of the present application;

[0035] Figure 5 A schematic diagram of the structure of a communication device provided in an embodiment of the present application;

[0036] Figure 6 A schematic diagram of the structure of a communication device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0037] The embodiments of the present application are described in detail below in conjunction with the accompanying drawings.

[0038] The switching method provided in the embodiment of the present application can be applied to the NTN system. The NTN system can use non-ground network devices such as drones, high altitude platform stations (HAPS), satellites, etc. to form a network and provide data transmission, voice communication and other services for terminal devices. In addition, the NTN system can also include other non-ground network devices, which are not limited in the present application.

[0039] The NTN system can also support various mobile communication systems, such as: new radio (NR) system, long term evolution (LTE) system or other communication systems such as future communication systems, but the specific ones are not limited here.

[0040] Taking satellites as an example of non-terrestrial network equipment in the NTN system, according to the satellite altitude, that is, the orbital altitude of the satellite, satellites can be divided into geostationary earth orbit (GEO) satellites, medium earth orbit (MEO) satellites and low-earth orbit (LEO) satellites. GEO is a synchronous earth satellite orbit. Satellites operating in this orbit are stationary relative to the ground. The orbital altitude of GEO is generally 35786 kilometers (km). LEO and MEO are collectively referred to as non-geostationary orbits (NGSO). Satellites operating in such orbits move at high speed relative to the ground. Among them, the orbital altitude of LEO is generally 160 to 2000 km, and the orbital altitude of MEO is generally 2000 to 35786 km. For NGSO, according to whether the satellite's beam moves with the satellite, it can be further divided into earth moving cells and geostationary cells (earth fixed cells or quasi-Earth fixed cells). For earth moving cells, the cell moves relative to the ground, and the satellite's beam pointing follows the satellite's movement. For earth fixed cells or quasi-Earth fixed cells, the cell is fixed relative to the ground for a certain period of time, and the satellite antenna can use its beamforming capability to point the beam to a certain area fixed on the ground for a certain period of time.

[0041] In the NTN system, the working modes of the NTN equipment may include: transparent mode and regenerative mode. According to the working mode of the NTN equipment, the architecture of the NTN system can be divided into the following two categories: one is the transparent forwarding architecture, in which the NTN equipment can be a relay or amplifier, and can perform RF filtering, amplification, etc., to regenerate the physical layer signal. The NTN equipment can be responsible for layer 1 (layer1, L1) relay, which is used for physical layer forwarding, and the upper layer is invisible. The second is the regenerative architecture, in which the NTN equipment has the processing function of the access network equipment. Exemplarily, the satellite in the regenerative working mode can be divided into a regenerative satellite without an intersatellite link, that is, there is no intersatellite link (ISL) between satellites; or a regenerative satellite with an intersatellite link, that is, there is an interface between satellites to directly exchange data, where the intersatellite link is an Xn port; or a regenerative satellite with a distributed unit (DU) processing function of an access network device, in which the satellite acts as a DU.

[0042] For example, Figure 1 A schematic diagram of an NTN system applicable to the embodiment of the present application is shown, and the NTN system may be a transparent forwarding architecture. Figure 1 In the system shown, the terminal device can communicate with the 5G core network (CN) through the access network, and then connect to the data network (DN) through the 5G CN. The satellite and NTN gateway can act as a relay device between the terminal device and the base station or as a remote radio unit (RRU) of the base station.

[0043] For example, Figure 2 Another NTN system schematic diagram applicable to the embodiment of the present application is shown, and the NTN system may be a regenerative architecture. Figure 2 In the system shown, the satellite can be used as a base station to form an access network with the NTN gateway, and communicate with the 5G CN through the NTN gateway, and then connect to the DN through the 5G CN. In addition, the satellite can also provide wireless access services for terminal devices. Figure 2 A regenerative satellite architecture without intersatellite links is illustrated.

[0044] It should be noted that Figure 1 and Figure 2Only one satellite and one NTN gateway are shown. In actual use, a plurality of satellites and / or a plurality of NTN gateways may be used as required. Each satellite may provide services to one or more terminal devices, each NTN gateway may correspond to one or more satellites, and each satellite may correspond to one or more NTN gateways, which are not specifically limited in the embodiments of the present application.

[0045] It should be noted that Figure 1 and Figure 2 This is only an example of the NTN system. The NTN system may also include other specific systems, which is not limited in this application.

[0046] The devices involved in the embodiments of the present application include terminal devices and network devices, and the network devices include, for example, ground network devices (such as access network devices) and non-ground network devices (such as satellites).

[0047] Terminal equipment, also known as user equipment (UE), mobile station (MS), mobile terminal (MT), etc., refers to equipment that provides voice and / or data connectivity to users. For example, the terminal equipment may be a handheld device, a vehicle-mounted device, etc. with a wireless connection function. At present, some examples of terminal equipment may be: mobile phones, tablet computers, laptop computers, PDAs, mobile internet devices (MID), wearable devices, virtual reality (VR) devices, augmented reality (AR) devices, wireless terminals in industrial control, wireless terminals in self driving, wireless terminals in remote medical surgery, wireless terminals in smart grids, wireless terminals in transportation safety, wireless terminals in smart cities, wireless terminals in smart homes, etc.

[0048] The access network device may refer to a radio access network (RAN) node (or device) that connects a terminal device to a wireless network, such as a base station. Some examples of RAN nodes may include: a gNB, a transmission reception point (TRP), an evolved NodeB (eNB), a radio network controller (RNC), a NodeB (NB), a base station controller (BSC), a base transceiver station (BTS), a home evolved NodeB (e.g., home NodeB, or home NodeB, HNB), a base band unit (BBU), or a wireless fidelity (Wifi) access point (AP).

[0049] In addition, in a network structure, the access network device may include a centralized unit (CU) node, a distributed unit (DU) node, or a CU node and a DU node. The RAN device including the CU node and the DU node splits the protocol layer of the gNB in ​​the NR system, places the functions of some protocol layers in the CU for centralized control, and distributes the functions of the remaining part or all of the protocol layers in the DU, which is centrally controlled by the CU, such as Figure 3As shown. Furthermore, CU can also be divided into control plane (CU-CP) and user plane (CU-UP). CU-CP is responsible for control plane functions, mainly including radio resource control (RRC) and packet data convergence protocol (PDCP) (i.e. PDCP-C) corresponding to the control plane. PDCP-C is mainly responsible for encryption and decryption, integrity protection, data transmission, etc. of control plane data. CU-UP is responsible for user plane functions, mainly including service data adaptation protocol (SDAP) and PDCP corresponding to the user plane (i.e. PDCP-U). SDAP is mainly responsible for processing the data of the core network and mapping the flow to the bearer. PDCP-U is mainly responsible for encryption and decryption, integrity protection, header compression, sequence number maintenance, data transmission, etc. of the data plane. CU-CP and CU-UP are connected through the E1 interface. CU-CP represents that gNB is connected to the core network through the NG interface, and is connected to DU through the F1 interface control plane (i.e. F1-C). CU-UP is connected to DU via F1 interface user plane (i.e. F1-U). Of course, another possible implementation is that PDCP-C is also in CU-UP.

[0050] It can be understood that in different systems, CU (including CU-CP or CU-UP) or DU may have different names, but those skilled in the art can understand their meanings. For example, in an open radio access network (O-RAN) system, CU may also be referred to as O-CU (open CU), DU may also be referred to as O-DU, CU-CP may also be referred to as O-CU-CP, and CU-UP may also be referred to as O-CU-UP. For the convenience of description, this application takes CU, CU-CP, CU-UP and DU as examples for description.

[0051] In the embodiments of the present application, the communication device for realizing the function of the network device or the terminal device may be the network device or the terminal device itself, or may be a device capable of supporting the network device or the terminal device to realize the function, such as a chip system, which may be installed in the network device or the terminal device. In the technical solution provided in the embodiments of the present application, the technical solution provided in the embodiments of the present application is described by taking the device for realizing the function of the network device as the network device and the device for realizing the function of the terminal device as the terminal device as an example.

[0052] In the embodiments of the present application, the number of nouns, unless otherwise specified, means "singular noun or plural noun", that is, "one or more". "At least one" means one or more, and "plurality" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. For example, A / B means: A or B. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of singular or plural items.

[0053] The ordinal numbers such as "first" and "second" mentioned in the embodiments of the present application are used to distinguish multiple objects, and are not used to limit the size, content, order, timing, priority or importance of the multiple objects. For example, the first system message and the second system message can be the same system message or different system messages, and such a name does not indicate the difference in priority or importance of the two system messages.

[0054] The above briefly introduces the communication system to which the embodiments of the present application are applicable. The following introduces the relevant technical solutions involved in the embodiments of the present application.

[0055] 1) System information (SI)

[0056] SI consists of a master information block (MIB) and multiple system information blocks (SIB). System information can be further divided into minimum SI and other SI. Minimum SI includes basic information required for initial access and information for obtaining any other SI.

[0057] The minimum SI includes MIB and SIB1. Among them, MIB contains cell barring status information and configuration information required for further receiving system messages, such as control resource set (CORSET) #0 configuration. MIB is broadcast periodically through the broadcast channel (BCH). SIB1 contains scheduling information of other SIBs and basic information required for initial access. SIB1 is also called remaining minimum system information (RMSI). SIB1 is broadcast periodically through the downlink shared channel (DL-SCH) or sent to terminal devices in the RRC connected state (RRC_CONNECTED) through dedicated signaling.

[0058] Other SI includes all SIBs that are not broadcast in the minimum SI. These SIBs can be broadcast periodically on DL-SCH, broadcast on-demand on DL-SCH, that is, a terminal device in RRC idle state (RRC_IDLE), RRC inactive state (RRC_INACTIVE) or RRC_CONNECTED sends a request to the network side, or sent in a dedicated manner on DL-SCH to a terminal device in RRC_CONNECTED.

[0059] The SIBs related to cell reselection include: SIB2, SIB3 and SIB4. Among them, SIB2 contains cell reselection information, which is mainly related to the serving cell; SIB3 contains the serving frequency and co-frequency neighboring cell information related to cell reselection (including cell reselection parameters common to the frequency and cell-specific reselection parameters); SIB4 contains information on other NR frequencies and inter-frequency neighboring cells related to cell reselection (including cell reselection parameters common to the frequency and cell-specific reselection parameters), which can also be used for NR idle / inactive state measurements;

[0060] The SIB currently carrying ephemeris information is SIB19 (NR NTN) or SIB31 (Internet of Things (IoT) NTN). SIB19 contains the information required for the cell access network in the NTN system, mainly including the ephemeris information of the satellite serving the cell, the ephemeris information of the satellite in the neighboring cell, the reference position of the serving cell, the distance threshold, the remaining service time and other parameters. Among them, the ephemeris information of the satellite includes orbital parameters, or parameters such as the satellite position calculated based on the orbital parameters. It can be understood that the ephemeris information of the satellite can be used to calculate, predict, depict, or track the time, position, speed and other states of the satellite flight.

[0061] 2) Cell reselection

[0062] The terminal device selects a cell with better signal quality to reside in through neighboring cell measurement. The terminal device considers two parameters when starting neighboring cell measurement: cell priority and signal quality of the current serving cell. Specifically, if the neighboring cell priority is higher than the current serving cell priority, the measurement is started unconditionally. If the neighboring cell priority is lower than or equal to the current serving cell priority, the terminal device measures the signal quality of the current serving cell and compares it with the quality standard sent by the network side. If the signal quality of the current serving cell of the terminal device is higher than the threshold, the neighboring cell measurement is not started, otherwise the neighboring cell measurement is started.

[0063] The terminal device can obtain neighboring cell information and priority information from the system message of the current serving cell. The neighboring cell information and priority information are generally configured by the network side and sent to the terminal device through cell broadcast. The value range of the cell reselection priority parameter (CellReselectionPriority) is (0-7). The larger the value of this parameter, the higher the reselection priority of all cells on the corresponding carrier frequency. NR also configures a cell reselection sub-priority parameter (CellReselectionSubPriority) for each carrier frequency, with a value of 0.2, 0.4, 0.6 or 0.8.

[0064] For example, if the neighbor cell priority is higher than the serving cell priority, the neighbor cell measurement is started unconditionally.

[0065] The neighboring cell priority is equal to the serving cell priority: If the neighboring cell and the serving cell are co-frequency cells, and the cell selection received signal strength value (Srxlev) of the serving cell is lower than or equal to the threshold SIntraSearchP, and the cell selection received signal quality value (Squal) of the serving cell is lower than or equal to the threshold SIntraSearchQ, the terminal device performs the neighboring cell intra-frequency measurement. If the neighboring cell and the serving cell are inter-frequency cells, and the serving cell's Srxlev is lower than or equal to the threshold SnonIntraSearchP, and the serving cell's Squal is lower than or equal to the threshold SnonIntraSearchQ, the terminal device performs the neighboring cell inter-frequency measurement.

[0066] The neighboring cell priority is lower than the serving cell priority: if the serving cell's Srxlev is lower than or equal to the threshold SnonIntraSearchP, and the serving cell's Squal is lower than or equal to the threshold SnonIntraSearchQ, the terminal device performs neighboring cell inter-frequency measurement or neighboring cell inter-system (inter-RAT) measurement.

[0067] 3) NTN-TN neighboring cell measurement

[0068] For the scenario where the terminal device reselects from the NTN cell to the TN cell, the terminal device needs to perform neighbor measurements on the TN cell (i.e., TN neighbor measurements). For example, in order to improve the efficiency of cell reselection or measurement of the terminal device, NTN will broadcast TN coverage information. After receiving the TN coverage information, the terminal device can determine whether to perform neighbor measurements on the TN cell based on the TN coverage information. If there is no TN coverage at the current location of the terminal device, the terminal device does not perform TN neighbor measurements, thereby reducing the measurement power consumption of the terminal device. For the scenario where the terminal device reselects from the TN cell to the NTN cell, the terminal device needs to perform neighbor measurements on the NTN cell (i.e., NTN neighbor measurements). For example, in order to improve the efficiency of cell reselection or measurement of the terminal device, TN will broadcast the ephemeris information of the NTN cell to assist the terminal device in performing neighbor measurements on the NTN cell. In addition, since the priority of NTN is lower than that of TN, the terminal device does not need to perform neighbor measurements on the NTN cell when there is TN coverage around the terminal device.

[0069] At present, after TN broadcasts the ephemeris information of the NTN cell, the terminal device will always maintain the ephemeris information of the NTN cell, that is, the terminal device will continue to read the system message to update the ephemeris information of the NTN cell. However, since the terminal device reads the ephemeris information of the NTN cell in order to perform neighboring cell measurements on the NTN cell, if the terminal device does not need to perform neighboring cell measurements on the NTN cell, then the terminal device does not need to read the ephemeris information of the NTN cell. Therefore, the terminal device unconditionally reads the ephemeris information of the NTN cell, which will only increase the measurement power consumption of the terminal device.

[0070] 4) Advance Neighborhood Measurement

[0071] The narrowband Internet of things (NB-IoT) introduces a connection-state neighbor measurement technology, which can carry out neighbor measurements in advance when the quality of the wireless link in the current service cell deteriorates, so that the RRC connection can be quickly reestablished when the terminal device detects a wireless link failure. Specifically, the terminal device is configured to perform neighbor measurements in advance based on the signal quality of the current service cell, or the distance between the terminal device and the reference position of the current service cell, or the remaining service time of the current service cell (or the time when the current service cell stops providing services to the covered area). Exemplarily, the process of early neighbor measurement is as follows:

[0072] When the terminal device changes from RRC_IDLE or RRC_INACTVE to RRC_CONNECTED, the terminal device can perform the following operations:

[0073] If SIB3 carries the configuration information of advance measurement (such as neighCellMeasCriteria), the terminal device sets the reference value (NRSRPRef) of the narrowband reference signal receiving power (NRSRP) to the latest serving cell measurement result, which can be used for cell selection or reselection. Among them, neighCellMeasCriteria contains two parameters: s-MeasureDeltaP and t-MeasureDeltaP, s-MeasureDeltaP indicates the change threshold of the NRSRP of the serving cell for the terminal device in RRC_CONNECTED to trigger the neighbor measurement, and t-MeasureDeltaP indicates the duration of the neighbor measurement for the terminal device in RRC_CONNECTED.

[0074] Alternatively, if the system message SIB3 carries neighCellMeasCriteria and the relaxed measurement conditions are not met, the terminal device starts timer T326 and sets the length of timer T326 to t-MeasureDeltaP. The relaxed measurement conditions refer to conditions under which the terminal device may not perform neighboring cell measurements, for example, if the terminal device is in the center of the cell, the terminal device may not perform neighboring cell measurements, or if the terminal device is moving at a low speed, the terminal device may not perform neighboring cell measurements or reduce neighboring cell measurements. Timer T326 is used to control the measurement time of advance measurement. If timer T326 times out, the terminal device stops advance measurement.

[0075] When the terminal device is in RRC_CONNECTED, the terminal device can perform the following operations:

[0076] If SIB3 carries neighCellMeasCriteria, and the difference between NRSRPRef and the first difference is higher than s-MeasureDeltaP, the terminal device can set NRSRPRef equal to the first difference, where the first difference is the difference between NRSRP and the transmit power offset (nrs-PowerOffsetNonAnchor), or the terminal device can start or restart timer T326 and set its length to t-MeasureDeltaP.

[0077] Alternatively, if SIB3 does not carry neighCellMeasCriteria or if timer T326 is running, the terminal device can perform neighbor cell intra-frequency measurement when the first difference is lower than the threshold s-MeasureIntra, and perform neighbor cell inter-frequency measurement when the first difference is lower than the threshold s-MeasureInter.

[0078] Alternatively, if SIB3 carries the service stop time (t-service) of the service cell, the terminal device can perform neighbor cell co-frequency measurement or neighbor cell inter-frequency measurement before the service stop time expires. The specific time of performing the neighbor cell measurement is up to the terminal device to implement. Alternatively, the terminal device can carry the neighbor cell service start time (or also called the neighbor cell coverage start time, such as t-ServiceStartNeigh) in SIB3, and perform neighbor cell co-frequency measurement or neighbor cell inter-frequency measurement at or after t-ServiceStartNeigh. The specific time of performing the neighbor cell measurement is up to the terminal device to implement.

[0079] Alternatively, if SIB3 carries the reference location (referenceLocation) and distance threshold (distanceThresh) of the serving cell, the terminal device may perform neighboring cell measurement when the distance between the terminal device and the reference location of the serving cell is lower than the distance threshold.

[0080] However, since the above neighboring cell measurement conditions only consider the signal quality of the current service cell, or the distance between the terminal device and the reference position of the current service cell, or the remaining service time of the current service cell, the priority of TN and NTN are not considered. If there is a TN neighboring cell, the terminal device does not need to perform neighboring cell measurement on the NTN cell. Unconditional neighboring cell measurement on the NTN cell will only increase invalid neighboring cell measurements of the terminal device, thereby increasing the measurement power consumption of the terminal device.

[0081] 5) Reading of ephemeris information

[0082] For NB-IoT, the ephemeris information of the satellite of the serving cell is carried in SIB31, for example, in SystemInformationBlockType31 (or for NB-IOT, the system message is SystemInformationBlockType31-NB). The ephemeris information of the satellite of the neighboring cell is carried in the newly defined SIB. For a terminal device in RRC_CONNECTED, the process of reading the ephemeris information of the serving cell is as follows: When the terminal device obtains the ephemeris information of the serving cell, the terminal device starts timer T317, for example, according to the reference start time (e.g., epoch time) of the validity period of the ephemeris information of the satellite specified in SystemInformationBlockType31, and the duration of timer T317 is the validity period of the ephemeris information of the satellite specified in SystemInformationBlockType31 (e.g., ul-syncValidityDuration). If timer T317 times out, the terminal device determines that the ephemeris information of the serving cell is expired. At this time, the terminal device can start timer T318 to obtain SIB31 and / or a new SIB carrying the ephemeris information of the neighboring cell. After the terminal device obtains the ephemeris information of the serving cell, it will stop timer T318, and the terminal device will no longer continue to read the ephemeris information of the neighboring cell after stopping timer T318. However, when the terminal device stops timer T318, the ephemeris information of the neighboring cell may not have been obtained. If timer T318 times out, for NB-IOT terminal devices that have not activated access side security and do not support optimization through control plane transmission, the terminal device enters RRC_IDLE. Otherwise, the terminal device initiates RRC reconstruction.

[0083] In order to solve the above-mentioned problem that the measurement power consumption of the terminal device is large due to the unconditional reading of ephemeris information and the unconditional neighboring cell measurement of the NTN cell, the embodiment of the present application provides the following solution of embodiment 1, which is described in detail below.

[0084] Example 1

[0085] The embodiment of the present application proposes a communication method to reduce the measurement power consumption of a terminal device. The method can be applied to a scenario where a terminal device reselects from a TN cell to an NTN cell and performs NTN neighbor cell measurement, or the method can be applied to a scenario where a terminal device in RRC_CONNECTED in NB-IoT performs NTN neighbor cell measurement in advance to quickly initiate RRC connection reconstruction.

[0086] like Figure 4As shown, a flow chart of a communication method provided by an embodiment of the present application is provided. In the following description, the method is performed by a network device (or a chip applied to a network device) and a terminal device (or a chip applied to a terminal device) as an example. The method includes:

[0087] S401: The network device broadcasts a first system message and a second system message. Correspondingly, the terminal device receives the first system message from the network device.

[0088] Among them, the first system message may include a first condition (also known as an ephemeris information reception and / or reading condition), and the first condition may be used for the terminal device to receive and / or read a second system message, and the second system information may include ephemeris information configured by the network device, and the ephemeris information is the ephemeris information of the NTN neighboring area of ​​the service cell. Optionally, the first system message may be SIB1, SIB2, SIB3, SIB4 or other system messages, and the second system message may be SIB19, SIB31 or other system messages. Optionally, the network device is a network device corresponding to a TN cell, which can be understood as the network device providing TN services for the terminal device, or the service cell of the terminal device is a TN cell. It can be understood that the terminal device in the implementation of this application is currently resident in or accessed to a cell under the network device.

[0089] Exemplarily, the network device may broadcast a second system message. The second system message may include satellite-related information. The satellite-related information may include NTN configuration information (NTN-Config), and the NTN configuration information includes parameters required for the terminal device to access the satellite, such as ephemeris information, common timing advance (TA), scheduling offset (K_offset), uplink synchronization time validity period, or ephemeris information validity period reference start time. The satellite-related information may also include one or more of the following: the out-of-service time of the serving cell, which indicates when the cell provided by the NTN quasi-earth fixed system stops serving the area currently covered; the reference position of the serving cell, which indicates the reference position of the cell provided by the NTN quasi-earth fixed system, and is used to start the location-based measurement in RRC_IDLE and RRC_INACTIVE; the distance threshold, which indicates the distance threshold from the reference position of the serving cell, and is used to start the location-based measurement in RRC_IDLE and RRC_INACTIVE; NTN neighbor cell configuration information (NTN-NeighCellConfig), which includes the configuration information of the satellite of the neighbor cell, the frequency information of the neighbor cell, and the cell identifier of the neighbor cell.

[0090] In a possible implementation manner, the first condition may include one or more of the following:

[0091] The signal quality of the serving cell is lower than or equal to the first threshold. The signal quality of the serving cell may be a reference signal received power (RSRP) of the serving cell, a reference signal received quality (RSRQ) of the serving cell, or a value determined based on the RSRP of the serving cell and the RSRQ of the serving cell, such as Srxlev of the serving cell and Squal of the serving cell;

[0092] Neighboring cell measurement conditions are met, where the neighboring cell measurement conditions may include high-priority neighboring cell measurement conditions, equal-priority neighboring cell measurement conditions, and low-priority neighboring cell measurement conditions. For example, the neighboring cell measurement conditions may include one or more of the following: the priority of the neighboring cell is higher than the priority of the serving cell, and the terminal device unconditionally starts the neighboring cell measurement; the priority of the neighboring cell is equal to the priority of the serving cell, if the neighboring cell and the serving cell are co-frequency cells, the Srxlev of the serving cell is lower than or equal to the threshold SIntraSearchP and the Squal of the serving cell is lower than or equal to the threshold SIntraSearchQ, then the terminal device starts the neighboring cell co-frequency measurement; if the neighboring cell and the serving cell are hetero-frequency cells, the Srxlev of the serving cell is lower than or equal to the threshold SnonIntraSearchP and the Squal of the serving cell is lower than or equal to the threshold SnonIntraSearchQ, then the terminal device starts the neighboring cell hetero-frequency measurement; the priority of the neighboring cell is lower than the priority of the serving cell, if the Srxlev of the serving cell is lower than or equal to the threshold SnonIntraSearchP and the Squal of the serving cell is lower than or equal to the threshold SnonIntraSearchQ, then the terminal device starts the neighboring cell hetero-frequency measurement or the neighboring cell hetero-system measurement;

[0093] The TN neighbor cell measurement conditions are met. The TN neighbor cell measurement conditions may include one or more of the following: the priority of the TN neighbor cell is higher than the priority of the serving cell, and the terminal device unconditionally starts the TN neighbor cell measurement; the priority of the TN neighbor cell is equal to the priority of the serving cell, if the TN neighbor cell and the serving cell are co-frequency cells, the Srxlev of the serving cell is lower than or equal to the threshold SIntraSearchP and the Squal of the serving cell is lower than or equal to the threshold SIntraSearchQ, then the terminal device starts the TN neighbor cell co-frequency measurement; if the TN neighbor cell and the serving cell are hetero-frequency cells, the Srxlev of the serving cell is lower than or equal to the threshold SnonIntraSearchP and the Squal of the serving cell is lower than or equal to the threshold SnonIntraSearchQ, then the terminal device starts the TN neighbor cell hetero-frequency measurement; the priority of the TN neighbor cell is lower than the priority of the serving cell, if the Srxlev of the serving cell is lower than or equal to the threshold SnonIntraSearchP and the Squal of the serving cell is lower than or equal to the threshold SnonIntraSearchQ, then the terminal device starts the TN neighbor cell hetero-frequency measurement or the neighbor cell hetero-system measurement;

[0094] Conduct TN neighboring cell measurements;

[0095] The signal quality of the TN neighboring cell of the serving cell is lower than or equal to the second threshold. Optionally, the priority of the TN neighboring cell of the serving cell is higher than the priority of the NTN neighboring cell of the serving cell. The signal quality of the TN neighboring cell of the serving cell may be the RSRP of the TN neighboring cell of the serving cell, the RSRQ of the TN neighboring cell of the serving cell, or a value determined based on the RSRP of the TN neighboring cell of the serving cell and the RSRQ of the TN neighboring cell of the serving cell, such as the Srxlev of the TN neighboring cell of the serving cell and the Squal of the TN neighboring cell of the serving cell;

[0096] Or, the priority of the NTN neighboring cell of the serving cell is higher than the priority of the serving cell.

[0097] In a possible implementation, the first threshold may be equal to the third threshold, and the second threshold may be higher than or equal to the third threshold. The third threshold may be a threshold corresponding to the above-mentioned TN neighboring area measurement condition. For example, the first threshold may be equal to the threshold SnonIntraSearchP and the threshold SnonIntraSearchQ, or may be the threshold SIntraSearchP and the threshold SIntraSearchQ. For another example, the second threshold may be higher or lower than the threshold SIntraSearchP and the threshold SIntraSearchQ, or may be higher or lower than the threshold SnonIntraSearchP and the threshold SnonIntraSearchQ.

[0098] S402: The terminal device determines whether a first condition is met, and receives and / or reads a second system message if the first condition is met.

[0099] Reading the second system message may be understood as reading the ephemeris information in the second system message.

[0100] Exemplarily, the first condition includes that the signal quality of the serving cell is lower than or equal to the first threshold, and the terminal device can receive and / or read the second system message when the signal quality of the serving cell is lower than or equal to the first threshold. Otherwise, the terminal device does not need to receive and / or read the second system message.

[0101] Alternatively, the above-mentioned first condition includes the above-mentioned TN neighbor area measurement condition or performs TN neighbor area measurement, and the terminal device can receive and / or read the second system message when the above-mentioned TN neighbor area measurement condition is met or the TN neighbor area measurement is performed. Otherwise, the terminal device does not need to receive and / or read the second system message. For example, since the terminal device will conditionally start the TN neighbor area measurement when the priority of the TN neighbor area is higher than the priority of the serving cell, and the terminal device will not unconditionally start the TN neighbor area measurement when the priority of the TN neighbor area is equal to or lower than the priority of the serving cell. Therefore, the terminal device may not immediately perform the TN neighbor area measurement after the priority of the TN neighbor area is equal to or lower than the priority of the serving cell and the above-mentioned TN neighbor area measurement condition is met, but first receive and / or read the second system message, which can be understood as the terminal device receiving and / or reading the second system message after the above-mentioned TN neighbor area measurement condition is met. Alternatively, the terminal device may also perform the TN neighbor area measurement after the above-mentioned TN neighbor area measurement condition is met, and receive and / or read the second system message at the same time.

[0102] Alternatively, the above-mentioned first condition includes that the signal quality of the TN neighboring area of ​​the serving cell is lower than or equal to the second threshold. Optionally, when the priority of the TN neighboring area of ​​the serving cell is higher than the priority of the NTN neighboring area of ​​the serving cell, the terminal device can receive and / or read the second system message when the signal quality of the TN neighboring area of ​​the serving cell is lower than or equal to the second threshold, and the priority of the TN neighboring area of ​​the serving cell is higher than the priority of the NTN neighboring area of ​​the serving cell. Otherwise, the terminal device does not need to receive and / or read the second system message. It can be understood that the terminal device can read the second system message when all TN neighboring areas with a priority higher than the NTN neighboring area have been measured for the neighboring area and the measured signal quality is lower than or equal to the second threshold. Or it can also be understood that the terminal device receives and / or reads the second system message when it is determined that the NTN neighboring area measurement is required. Alternatively, the terminal device can receive and / or read the second system message when the priority of the NTN neighboring area of ​​the serving cell is higher than the priority of the serving cell.

[0103] Alternatively, the first condition includes the neighboring cell measurement condition, and the terminal device may receive and / or read the second system message when the neighboring cell measurement condition is met. Otherwise, the terminal device does not need to receive and / or read the second system message.

[0104] According to the above scheme, the terminal device can read the ephemeris information only when the signal quality of the serving cell is lower than or equal to the first threshold, or meets the TN neighbor area measurement conditions, or meets the neighbor area measurement conditions, or performs TN neighbor area measurement, or the signal quality of the TN neighbor area of ​​the serving cell is lower than or equal to the second threshold, or the priority of the NTN neighbor area of ​​the serving cell is higher than the priority of the serving cell, thereby reducing the invalid reading of the ephemeris information and reducing the measurement power consumption of the terminal device.

[0105] In a possible implementation manner, the first system message may include the first condition and the second condition (also referred to as enhanced NTN neighbor cell measurement condition) mentioned above, or the first system message may not include the first condition mentioned above but only include the second condition.

[0106] The second condition may include that the signal quality of the TN neighboring cell of the serving cell is lower than or equal to the second threshold. Optionally, the priority of the TN neighboring cell of the serving cell is higher than the priority of the NTN neighboring cell of the serving cell.

[0107] The unenhanced NTN neighbor cell measurement conditions are the same as the above-mentioned TN neighbor cell measurement conditions. For example, the unenhanced NTN neighbor cell measurement conditions may include one or more of the following: the priority of the NTN neighbor cell is higher than the priority of the serving cell, and the terminal device unconditionally starts the NTN neighbor cell measurement; the priority of the NTN neighbor cell is equal to the priority of the serving cell. If the NTN neighbor cell and the serving cell are co-frequency cells, the Srxlev of the serving cell is lower than or equal to the threshold SIntraSearchP and the Squal of the serving cell is lower than or equal to the threshold SIntraSearchQ, then the terminal device starts the NTN neighbor cell co-frequency measurement. If the NTN If the neighboring cell and the serving cell are inter-frequency cells, the Srxlev of the serving cell is lower than or equal to the threshold SnonIntraSearchP and the Squal of the serving cell is lower than or equal to the threshold SnonIntraSearchQ, the terminal device starts the NTN neighboring cell inter-frequency measurement; the priority of the NTN neighboring cell is lower than the priority of the serving cell. If the Srxlev of the serving cell is lower than or equal to the threshold SnonIntraSearchP and the Squal of the serving cell is lower than or equal to the threshold SnonIntraSearchQ, the terminal device starts the NTN neighboring cell inter-frequency measurement or the neighboring cell inter-system measurement.

[0108] The terminal device can perform NTN neighbor cell measurement when the above second condition is met. It can be understood that the terminal device can perform NTN neighbor cell measurement when all TN neighbor cells with a higher priority than the NTN neighbor cell have been measured and the measured signal quality is lower than or equal to the second threshold. Optionally, the terminal device can perform NTN neighbor cell measurement when the above unenhanced NTN neighbor cell measurement conditions are met.

[0109] Exemplarily, the priority of the TN neighboring cell is higher than the priority of the serving cell:

[0110] The terminal device unconditionally starts the TN neighbor cell measurement and obtains the Srxlev and Squal of the TN neighbor cell. If the Srxlev of the TN neighbor cell is lower than or equal to the threshold SIntraSearchP, and the Squal of the TN neighbor cell is lower than or equal to the threshold SIntraSearchQ, or if the Srxlev of the TN neighbor cell is lower than or equal to the threshold SnonIntraSearchP, and the Squal of the TN neighbor cell is lower than or equal to the threshold SnonIntraSearchQ, the terminal device performs NTN neighbor cell measurement.

[0111] The priority of the TN neighbor cell is equal to the priority of the serving cell:

[0112] If the TN neighbor cell and the serving cell are co-frequency cells, the Srxlev of the serving cell is lower than or equal to the threshold SIntraSearchP and the Squal of the serving cell is lower than or equal to the threshold SIntraSearchQ, the terminal device starts the TN neighbor cell co-frequency measurement to obtain the Srxlev of the TN neighbor cell and the Squal of the TN neighbor cell. If the Srxlev of the TN neighbor cell is lower than or equal to the threshold SIntraSearchP and the Squal of the TN neighbor cell is lower than or equal to the threshold SIntraSearchQ, the terminal device performs NTN neighbor cell measurement.

[0113] If the TN neighbor cell and the serving cell are inter-frequency cells, the Srxlev of the serving cell is lower than or equal to the threshold SnonIntraSearchP and the Squal of the serving cell is lower than or equal to the threshold SnonIntraSearchQ, the terminal device starts the TN neighbor cell inter-frequency measurement to obtain the Srxlev of the TN neighbor cell and the Squal of the TN neighbor cell. If the Srxlev of the TN neighbor cell is lower than or equal to the threshold SnonIntraSearchP and the Squal of the TN neighbor cell is lower than or equal to the threshold SnonIntraSearchQ, the terminal device performs NTN neighbor cell measurement.

[0114] The priority of the TN neighbor cell is lower than that of the serving cell:

[0115] If the Srxlev of the serving cell is lower than or equal to the threshold SnonIntraSearchP and the Squal of the serving cell is lower than or equal to the threshold SnonIntraSearchQ, the terminal device starts the TN neighbor cell heterogeneous frequency measurement or the neighbor cell heterogeneous system measurement to obtain the Srxlev of the TN neighbor cell and the Squal of the TN neighbor cell. If the Srxlev of the TN neighbor cell is lower than or equal to the threshold SnonIntraSearchP and the Squal of the TN neighbor cell is lower than or equal to the threshold SnonIntraSearchQ, the terminal device performs NTN neighbor cell measurement.

[0116] In a possible implementation, the terminal device may receive and / or read the second system message before performing the NTN neighboring cell measurement when the first condition is not met but the second condition is met. Otherwise, the terminal device does not need to receive and / or read the second system message.

[0117] In a possible implementation, the terminal device may receive and / or read the second system message when the first condition is not met and the first system message also includes the first indication information. Otherwise, the terminal device does not need to receive and / or read the second system message. The first indication information is used to indicate that the second system message includes ephemeris information.

[0118] Exemplarily, when the terminal device changes from RRC_IDLE or RRC_INACTVE to RRC_CONNECTED, the terminal device may perform the following operations:

[0119] If SIB3 carries neighCellMeasCriteria, the terminal device sets NRSRPRef to the latest serving cell measurement result, which can be used for cell selection or reselection.

[0120] Alternatively, if the system message SIB3 carries neighCellMeasCriteria and the relaxed measurement condition is not met, the terminal device starts timer T326 and sets the length of timer T326 to t-MeasureDeltaP.

[0121] When the terminal device is in the RRC_CONNECTED state, the terminal device can perform the following operations:

[0122] If SIB3 carries neighCellMeasCriteria, and the difference between NRSRPRef and the first difference is higher than s-MeasureDeltaP, the terminal device can set NRSRPRef equal to the first difference, where the first difference is the difference between NRSRP and nrs-PowerOffsetNonAnchor, or the terminal device can start or restart timer T326 and set its length to t-MeasureDeltaP.

[0123] Alternatively, if neighCellMeasCriteria is not carried in SIB3 or if timer T326 is running, the terminal device can perform neighbor cell intra-frequency measurement when the first difference is lower than the threshold s-MeasureIntra, and perform TN neighbor cell inter-frequency measurement when the first difference is lower than the threshold s-MeasureInter.

[0124] Further, if the signal quality of the TN neighboring cell of the serving cell is lower than or equal to the second threshold, the terminal device can perform NTN neighboring cell measurement, and optionally, the priority of the TN neighboring cell of the serving cell is higher than the priority of the NTN neighboring cell of the serving cell. It can be understood that the terminal device can perform NTN neighboring cell measurement under the condition of satisfying the enhanced NTN neighboring cell measurement condition. The enhanced NTN neighboring cell measurement condition includes that the signal quality of the TN neighboring cell of the serving cell is lower than or equal to the second threshold, and optionally, the priority of the TN neighboring cell of the serving cell is higher than the priority of the NTN neighboring cell of the serving cell.

[0125] Optionally, the terminal device may receive and / or read the second system message when one or more of the following is met: the signal quality of the serving cell is lower than or equal to the first threshold; the neighboring area measurement condition is met; the TN neighboring area measurement condition is met; the TN neighboring area measurement is performed; the NTN neighboring area measurement condition is met; or the NTN neighboring area measurement is performed. Otherwise, the terminal device does not need to receive and / or read the second system message. The terminal device may then perform NTN neighboring area measurement based on the ephemeris information read from the second system message. The NTN neighboring area measurement condition may be the enhanced NTN neighboring area measurement condition described above, or it may be the unenhanced NTN neighboring area measurement condition described above.

[0126] Alternatively, if SIB3 carries the service outage time of the serving cell, the terminal device may perform neighbor cell co-frequency measurement or neighbor cell inter-frequency measurement before the service outage time expires. The specific time for performing the neighbor cell measurement is up to the terminal device to implement. Alternatively, the terminal device may perform neighbor cell co-frequency measurement or neighbor cell inter-frequency measurement when t-ServiceStartNeigh arrives or after SIB3 carries t-ServiceStartNeigh. The specific time for performing the neighbor cell measurement is up to the terminal device to implement.

[0127] Alternatively, if SIB3 carries the reference position and distance threshold of the serving cell, the terminal device may perform neighboring cell measurement when the distance between the terminal device and the reference position of the serving cell is lower than the distance threshold.

[0128] According to the above scheme, the terminal device can perform neighbor cell measurement on the NTN cell only when the signal quality of the TN neighbor cell of the serving cell is lower than or equal to the second threshold, thereby reducing invalid measurements of the NTN neighbor cell and reducing the measurement power consumption of the terminal device.

[0129] In order to solve the above-mentioned problem that the terminal device stops timer T318 because it obtains the ephemeris information of the service cell, resulting in the ephemeris information of the neighboring cell not being obtained, the present application implements the solution of the following embodiment 2, which can be implemented in combination with the above-mentioned embodiment 1, and is described in detail below.

[0130] Example 2

[0131] In this embodiment 2, the terminal device may postpone stopping timer T318. Specifically, if timer T317 times out, the terminal device may start timer T318 and obtain SIB31. Further, if the ephemeris information of the neighboring cell expires, the terminal device may obtain a new SIB carrying the ephemeris information of the neighboring cell. The terminal device may stop timer T318 after successfully acquiring SIB31 and a new SIB carrying the ephemeris information of the neighboring cell. Optionally, timer T317 may correspond to the ephemeris information of the serving cell (i.e., the ephemeris information of the serving cell expires when timer T317 times out), or, timer T317 may correspond to the ephemeris information of the neighboring cell (i.e., the ephemeris information of the neighboring cell expires when timer T317 times out). When timer T318 stops or times out, the terminal device no longer reads SIB31 and the new SIB carrying the ephemeris information of the neighboring cell.

[0132] Alternatively, the terminal device may define a new timer T318x. Timer T318x may correspond to the time for acquiring the ephemeris information of the neighboring cell, and timer T318 may correspond to the time for acquiring the ephemeris information of the serving cell. The terminal device may continue to read the ephemeris information of the neighboring cell when timer T318 stops or times out, and may stop timer T318x when the ephemeris information of the neighboring cell is successfully acquired.

[0133] Specifically, if timer T317 times out, the terminal device may start timer T318 and obtain SIB31. Furthermore, if the ephemeris information of the neighboring cell expires, the terminal device may obtain a new SIB carrying the ephemeris information of the neighboring cell. The terminal device may stop timer T318 if SIB31 is successfully obtained. If the ephemeris information of the neighboring cell expires or the terminal device has not yet obtained a new SIB carrying the ephemeris information of the neighboring cell, the terminal device may start timer T318x, after which the terminal device may stop timer T318x if the ephemeris information of the neighboring cell is successfully obtained. Optionally, timer T317 may correspond to the ephemeris information of the serving cell (i.e., the ephemeris information of the serving cell expires when timer T317 times out), or, timer T317 may correspond to the ephemeris information of the neighboring cell (i.e., the ephemeris information of the neighboring cell expires when timer T317 times out). When timer T318 stops or times out, for NB-IOT terminal devices that have not activated access side security and do not support optimization through control plane transmission, the terminal device enters RRC_IDLE, otherwise the terminal device initiates RRC reconstruction. When T318x stops or times out, the terminal device no longer reads the new SIB carrying the ephemeris information of the neighboring cells.

[0134] Alternatively, the terminal device may define a new timer T318y. Timer T318y may correspond to the time for acquiring the ephemeris information of the neighboring cell, and timer T318 may correspond to the time for acquiring the ephemeris information of the serving cell. The terminal device may stop timer T318y if the ephemeris information of the neighboring cell is successfully acquired.

[0135] Specifically, if timer T317 times out, the terminal device can start timer T318 and obtain SIB31. Further, if the ephemeris information of the neighboring cell expires, the terminal device can start timer T318y and obtain a new SIB carrying the ephemeris information of the neighboring cell. The terminal device can stop timer T318 if SIB31 is successfully acquired. At this time, although the terminal device stops acquiring SIB 31, it can continue to acquire the ephemeris information of the neighboring cell. The terminal device can stop timer T318y if the ephemeris information of the neighboring cell is successfully acquired. At this time, although the terminal device stops acquiring the new SIB carrying the ephemeris information of the neighboring cell, it can continue to acquire SIB31. Optionally, timer T317 may correspond to the ephemeris information of the serving cell (i.e., the ephemeris information of the serving cell expires when timer T317 times out), or timer T317 may correspond to the ephemeris information of the neighboring cell (i.e., the ephemeris information of the neighboring cell expires when timer T317 times out). When timer T318 stops or times out, for NB-IOT terminal devices that have not activated access side security and do not support transmission optimization through the control plane, the terminal device enters RRC_IDLE, otherwise the terminal device initiates RRC reconstruction. When timer T318y stops or times out, the terminal device may no longer read the new SIB carrying the ephemeris information of the neighboring cells.

[0136] According to the above solution, the terminal device can postpone stopping timer T318 or newly define a new timer to control the reading of the ephemeris information of the neighboring cells, thereby ensuring that the terminal device successfully obtains the ephemeris information of the neighboring cells.

[0137] In the embodiment of the present application, the network device or the terminal device can perform some or all of the steps in the embodiment of the present application, and these steps or operations are only examples. The embodiment of the present application can also perform other operations or variations of various operations. In addition, each step can be performed in a different order presented in the embodiment of the present application, and it is possible not to perform all the operations in the embodiment of the present application.

[0138] In order to implement the functions in the above embodiments, the network device or terminal device includes a hardware structure and / or software module corresponding to each function. It should be easily appreciated by those skilled in the art that the present application can be implemented in the form of hardware or a combination of hardware and computer software in combination with the units and method steps of each example described in the embodiments disclosed in this application. Whether a function is executed in the form of hardware or computer software driving hardware depends on the specific application scenario and design constraints of the technical solution.

[0139] Figure 5 and Figure 6A schematic diagram of the structure of a possible communication device provided for an embodiment of the present application. These communication devices can be used to implement the functions of the network device or terminal device in the above method embodiment, and thus can also achieve the beneficial effects possessed by the above method embodiment. In an embodiment of the present application, the communication device can be a network device or a terminal device, and can also be a module (such as a chip) applied to a network device or a terminal device.

[0140] Figure 5 The communication device 500 shown includes a processing unit 510 and a communication unit 520. The communication device 500 is used to implement the functions of the network device or the terminal device in the above method embodiment.

[0141] When the communication device 500 is used to implement the functions of the terminal device in the above embodiment:

[0142] A communication unit, configured to receive a first system message from a network device, wherein the first system message includes a first condition, and the first condition is used by the terminal device to determine whether to receive and / or read a second system message, wherein the second system message includes ephemeris information configured by the network device;

[0143] The processing unit is used to determine whether the first condition is met; if the first condition is met, receive and / or read the second system message.

[0144] When the communication device 500 is used to implement the functions of the network device in the above embodiment:

[0145] A communication unit is used to broadcast a first system message and a second system message, wherein the first system message includes a first condition, and the first condition is used by a terminal device to determine whether to receive and / or read the second system message, and the second system message includes ephemeris information configured by the network device.

[0146] For a more detailed description of the processing unit 510 and the communication unit 520, reference may be made to the relevant description in the above method embodiment, which will not be repeated here.

[0147] Figure 6 The communication device 600 shown includes a processor 610 and an interface circuit 620. The processor 610 and the interface circuit 620 are coupled to each other. The interface circuit 620 can be a transceiver or an input-output interface. Exemplarily, the communication device 600 can also include a memory 630 for storing instructions executed by the processor 610 or storing input data required by the processor 610 to execute instructions or storing data generated after the processor 610 executes instructions.

[0148] When the communication device 600 is used to implement the above method embodiment, the processor 610 is used to implement the function of the above processing unit 510 , and the interface circuit 620 is used to implement the function of the above communication unit 520 .

[0149] When the above communication device is a chip applied to a terminal device, the chip of the terminal device implements the functions of the terminal device in the above method embodiment. The chip of the terminal device receives information from other modules in the terminal device (such as a radio frequency module or an antenna), and the information is sent to the terminal device by the network device; or the chip of the terminal device sends information to other modules in the terminal device (such as a radio frequency module or an antenna), and the information is sent to the network device by the terminal device.

[0150] When the above-mentioned communication device is a module applied to a network device, the module of the network device implements the function of the network device in the above-mentioned method embodiment. The module of the network device receives information from other modules in the network device (such as a radio frequency module or an antenna), and the information is sent by the terminal device to the network device; or, the module of the network device sends information to other modules in the network device (such as a radio frequency module or an antenna), and the information is sent by the network device to the terminal device. The module of the network device here can be a chip of the network device, or it can be a DU or other module, and the DU here can be a DU under the open radio access network (open radio access network, O-RAN) architecture.

[0151] The processor in the embodiments of the present application may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, transistor logic devices, hardware components or any combination thereof. The general-purpose processor may be a microprocessor or any conventional processor.

[0152] The method steps in the embodiments of the present application can be implemented by hardware, or by a processor executing software instructions. The software instructions can be composed of corresponding software modules, and the software modules can be stored in random access memory, flash memory, read-only memory, programmable read-only memory, erasable programmable read-only memory, electrically erasable programmable read-only memory, register, hard disk, mobile hard disk, compact disc read-only memory (compact disc read-only memory, CD-ROM) or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor so that the processor can read information from the storage medium and write information to the storage medium. Of course, the storage medium can also be a component of the processor. The processor and the storage medium can be located in an ASIC. In addition, the ASIC can be located in a network device or a terminal device. Of course, the processor and the storage medium can also be present in a network device or a terminal device as discrete components.

[0153] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0154] Those of ordinary skill in the art will appreciate that the various illustrative logical blocks and steps described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or in a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel may use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0155] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0156] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0157] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0158] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the part of the technical solution of the present application that contributes essentially or the part of the technical solution can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as USB flash drives, mobile hard disks, read-only memories (ROM), RAM, magnetic disks or optical disks.

[0159] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A communication method, characterized in that: The method is performed by a terminal device or a chip applied to the terminal device, and includes: Receiving a first system message from a network device, the first system message including a first condition, the first condition being used by the terminal device to determine whether to receive and / or read a second system message, the second system message including ephemeris information configured by the network device; determining whether the first condition is met; When the first condition is met, the second system message is received and / or read.

2. The method according to claim 1, characterized in that The first condition includes one or more of the following: The signal quality of the serving cell of the terminal device is lower than or equal to the first threshold; Meet the ground network TN neighboring area measurement conditions; Conduct TN neighboring cell measurements; The signal quality of the TN neighboring cell of the serving cell of the terminal device is lower than or equal to the second threshold; or, The priority of the non-terrestrial network NTN neighboring cell of the service cell of the terminal equipment is higher than the priority of the service cell.

3. The method according to claim 2, characterized in that If the signal quality of the TN neighboring cell of the service cell of the terminal device is lower than or equal to the second threshold, the priority of the TN neighboring cell is higher than the priority of the NTN neighboring cell of the service cell.

4. The method according to any one of claims 1 to 3, characterized in that: The first system message further includes a second condition; and the method further includes: When the second condition is met, NTN neighbor cell measurement is performed, and the second condition includes that the signal quality of the TN neighbor cell of the service cell of the terminal device is lower than or equal to the second threshold.

5. The method according to claim 4, characterized in that The priority of the TN neighboring cell is higher than the priority of the NTN neighboring cell of the serving cell.

6. The method according to claim 4 or 5, characterized in that The method further comprises: When the first condition is not met but the second condition is met, the second system message is received and / or read before performing the NTN neighbor cell measurement.

7. The method according to claim 4 or 5, characterized in that The method further comprises: In a case where the first condition is not met and the first system message further includes first indication information, the second system message is received and / or read, where the first indication information is used to indicate that the second system message includes the ephemeris information.

8. The method according to claim 2, characterized in that The first threshold is equal to the third threshold, and the third threshold is a threshold corresponding to the TN neighboring cell measurement condition.

9. The method according to any one of claims 2 to 4, characterized in that: The second threshold is higher than or equal to the third threshold, and the third threshold is a threshold corresponding to the TN neighboring cell measurement condition.

10. A communication method, characterized in that: The method is performed by a network device or a chip applied to the network device, and includes: A first system message and a second system message are broadcasted, wherein the first system message includes a first condition, and the first condition is used for a terminal device to determine whether to receive and / or read the second system message, and the second system message includes ephemeris information configured by the network device.

11. The method according to claim 10, characterized in that The first condition includes one or more of the following: The signal quality of the serving cell of the terminal device is lower than or equal to the first threshold; Meet the TN neighboring cell measurement conditions; Conduct TN neighboring cell measurements; The signal quality of the TN neighboring cell of the serving cell of the terminal device is lower than or equal to the second threshold; or, The priority of the NTN neighboring cell of the service cell of the terminal device is higher than the priority of the service cell.

12. The method according to claim 11, characterized in that If the signal quality of the TN neighboring cell of the service cell of the terminal device is lower than or equal to the second threshold, the priority of the TN neighboring cell is higher than the priority of the NTN neighboring cell of the service cell.

13. The method according to any one of claims 10-11, characterized in that: The first system message also includes a second condition, which is used by the terminal device to perform NTN neighbor cell measurement. The second condition includes that the signal quality of the TN neighbor cell of the service cell of the terminal device is lower than or equal to a second threshold.

14. The method according to claim 13, characterized in that The priority of the TN neighboring cell is higher than the priority of the NTN neighboring cell of the serving cell.

15. The method according to claim 11, characterized in that The first threshold is equal to the third threshold, and the third threshold is a threshold corresponding to the TN neighboring cell measurement condition.

16. The method according to any one of claims 11 to 13, characterized in that: The second threshold is higher than or equal to the third threshold, and the third threshold is a threshold corresponding to the TN neighboring cell measurement condition.

17. A communication device, characterized in that: The method comprises a module for executing the method as claimed in any one of claims 1 to 9, or a module for executing the method as claimed in any one of claims 10 to 16.

18. A communication device, characterized in that: The invention comprises a processor and an interface circuit, wherein the interface circuit is used to receive signals from other communication devices outside the communication device and transmit them to the processor or send signals from the processor to other communication devices outside the communication device, and the processor implements the method as described in any one of claims 1 to 9 or the method as described in any one of claims 10 to 16 through a logic circuit or by executing code instructions.

19. A communication device, characterized in that: include: Memory for storing computer programs; A processor, configured to call and run the computer program from the memory to implement the method according to any one of claims 1 to 9, or to implement the method according to any one of claims 10 to 16.

20. A chip system, characterized in that: include: Memory for storing computer programs; A processor, configured to call and run the computer program from the memory, so that a device equipped with the chip system executes the method as claimed in any one of claims 1 to 9, or executes the method as claimed in any one of claims 10 to 16.

21. A computer program product, characterized in that The invention comprises a computer program, which, when executed by a communication device, implements the method according to any one of claims 1 to 16.

22. A computer-readable storage medium, characterized in that: The storage medium stores a computer program or an instruction, and when the computer program or the instruction is executed by the communication device, the method according to any one of claims 1 to 16 is implemented.

23. A communication system, characterized in that: include: A terminal device, configured to execute the method according to any one of claims 1 to 9; A network device, configured to execute the method according to any one of claims 10 to 16.

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