Communication method and apparatus

Abstract

The embodiments of the present application provide a communication method and apparatus, which aim to solve the problem of non-compliance with the requirements of specific zones when terminal devices communicate on restricted frequency bands within said specific zones. The present application uses entry by a terminal device into a first zone as a trigger condition for an RRC reestablishment procedure, so that when entering the first zone, the terminal device suspends communication by triggering the RRC reestablishment procedure, thereby preventing, to a certain extent, communication on a specific frequency band within the first zone after entering the first zone, and reducing the likelihood of non-compliance with requirements of said zone. In addition, the present application allows for a terminal device to autonomously avoid communication on a specific frequency band, thereby helping to mitigate decision-making risks of network sides, such as operators, and improving flexibility in decision-making by terminal devices.

Description

A communication method and apparatus

[0001] Cross-references to related applications

[0002] This application claims priority to Chinese Patent Application No. 202411640640.9, filed on November 15, 2024, entitled "A Communication Method and Apparatus", the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of communication technology, and in particular to a communication method and apparatus. Background Technology

[0004] The demand for unrewed aerial vehicles (UAVs) is growing rapidly. When UAVs operate in the air, certain special communication services or areas require additional spectrum usage restrictions to ensure that specific communication services (such as emergency services) are not interfered with. For example, if a no-transmit zone (NTZ) is defined as a geographical area where UAVs are not allowed to communicate on certain specific frequency bands, when a UAV passes through an NTZ, if its operating frequency is outside the restricted band, then the UAV will continue to operate unaffected; however, if its operating frequency is within the restricted band, then the original data transmission service should be immediately stopped to ensure that the UAV does not transmit any information within the NTZ, otherwise it will be considered as not meeting the requirements of the no-transmit zone. Therefore, how to prevent UAVs from transmitting data on restricted frequency bands after passing through these areas has become an urgent problem to be solved. Summary of the Invention

[0005] This application provides a communication method and apparatus to solve the problem that communication by a terminal device in a limited frequency band in a specific area fails to meet the requirements of that area.

[0006] Firstly, this application provides a communication method, wherein the execution subject of the method is a terminal device or a module or chip within the terminal device; the method is described here using a terminal device as the execution subject as an example. The method includes: starting a first timer after determining that a first area has been entered, and performing cell selection during the timer's duration. The first area is a geographical area where communication on a specific frequency band is not permitted; the first timer is used to control the duration required for the cell selection process.

[0007] This application uses entering the first region as a trigger condition for the RRC re-establishment process. This allows the terminal device to terminate communication upon entering the first region by triggering the RRC re-establishment process, thereby avoiding communication on specific frequency bands within the first region and reducing the probability of not meeting the region's requirements. Furthermore, this application enables the terminal device to autonomously avoid communication on specific frequency bands, which helps reduce decision-making risks for network sides, such as operators, and improves the decision-making flexibility of the terminal device.

[0008] In one possible design, cell selection includes: selecting cells based on at least one of the following: a specific frequency band, or the cell priority of at least one cell; wherein the cell priority of a cell whose operating frequency band belongs to the specific frequency band is lower than the cell priority of a cell whose operating frequency band does not belong to the specific frequency band. This approach, by considering the specific frequency band and the cell priority associated with it, can reduce the probability that the terminal device will communicate on a specific frequency band where communication is restricted in the first area, thus reducing the probability of not meeting the requirements of that area.

[0009] In one possible design, the method further includes receiving cell priority information for at least one of the aforementioned cells. This approach helps reduce the probability of the terminal device communicating on a specific frequency band with limited communication in the first area, thereby reducing the likelihood of not meeting the requirements of that area.

[0010] In one possible design, a specific frequency band may include one or more frequency bands.

[0011] In one possible design, cell selection based on a specific frequency band includes: performing a cell search and selecting a first cell; if the operating frequency band of the first cell does not belong to the specific frequency band, initiating random access to the first cell; if the operating frequency band of the first cell belongs to the specific frequency band, waiting for the first timer to expire. This design can, on the one hand, prevent terminal devices from communicating on specific frequency bands where communication is restricted in the first area, reducing the probability of not meeting the requirements of that area; on the other hand, it allows terminal devices to restore communication promptly, reducing the duration of communication interruptions.

[0012] In one possible design, the method further includes: if the terminal device leaves the first area during the waiting period for the first timer to expire, reselecting a cell before the first timer expires. This approach, by providing a mechanism for reselecting a cell after the terminal device leaves the first area, allows the terminal device to promptly select a suitable cell to resume communication without waiting for the first timer to expire. This helps reduce the duration of communication interruptions for the terminal device and improves the user experience.

[0013] In one possible design, the method further includes: if the terminal device does not leave the first area during the waiting period for the first timer to expire, it enters the Radio Resource Control (RRC) idle state after the first timer expires. This method, by keeping the terminal device in the RRC idle state, can prevent the terminal device from communicating on specific frequency bands where communication is restricted in the first area, reducing the probability of not meeting the requirements of that area.

[0014] In one possible design, the method further includes: determining whether to leave the first area after the first timer expires; and establishing an RRC connection with the access network device. This design allows the terminal device to resume communication promptly, reducing communication interruption time and improving user experience.

[0015] In one possible design, establishing an RRC connection with the access network device includes: restoring a first communication service, wherein the first communication service is a communication service that was suspended before the start of a first timer; and establishing an RRC connection with the access network device upon triggering the first communication service. This design facilitates timely communication recovery for the terminal device.

[0016] In one possible design, after determining that the device is about to enter the first area, the method further includes suspending ongoing communication services. This design, by suspending communication services, can prevent the terminal device from communicating on specific frequency bands where communication is restricted in the first area, reducing the probability of not meeting the requirements of that area.

[0017] In one possible design, determining entry into the first area includes: determining entry into and / or exit from the first area based on the distance between the first area and the terminal device. This design balances the communication assurance of the terminal device with the risk of not meeting the requirements of the area.

[0018] In one possible design, the method further includes determining the distance between the first area and the terminal device based on at least one of the following: the location of the first area and the location of the terminal device. This design helps to balance the communication assurance of the terminal device with the risk of not meeting the requirements of the area.

[0019] In one possible design, the distance between the first region and the terminal device is determined based on at least one of the following: the location of the first region and the location of the terminal device, including: determining at least one distance between the first region and the terminal device based on the location of at least one boundary point of the first region and the location of the terminal device; and determining the minimum distance among the at least one distance as the distance between the first region and the terminal device.

[0020] In one possible design, the distance between the first region and the terminal device is determined based on at least one of the following: the location of the first region and the location of the terminal device, including: determining at least one distance between the first region and the terminal device based on the latitude and longitude range and / or altitude range of the first region and the location of the terminal device; and determining the minimum distance among the at least one distance as the distance between the first region and the terminal device.

[0021] In one possible design, the distance between the first area and the terminal device is determined based on at least one of the following: the location of the first area and the location of the terminal device, including: determining the distance between the first area and the terminal device based on the location of the center point of the first area and the location of the terminal device.

[0022] In one possible design, determining entry into and / or exit from the first area based on the distance between the first area and the terminal device includes: determining entry into the first area if the distance between the first area and the terminal device is less than or equal to a first threshold value; and / or determining exit from the first area if the distance between the first area and the terminal device is greater than or equal to the first threshold value.

[0023] In one possible design, the method further includes: receiving location information of a first region, the location information of the first region being used to indicate the location of the first region.

[0024] In one possible design, the location information of the first region indicates at least one of the following: the latitude and longitude range and / or altitude range of the first region, the location of the center point of the first region, and the location of at least one boundary point of the first region.

[0025] In one possible design, the first threshold value is indicated by the core network equipment or USS, etc.

[0026] In one possible design, the first threshold value is determined by the terminal device.

[0027] Secondly, this application provides a communication method, wherein the execution subject of the method is a network device or a module or chip within a network device, wherein the network device can be a USS or a core network device, etc. The method is described here using a network device as the execution subject. The method includes: determining the cell priority of at least one cell, and sending information about the cell priority of the at least one cell.

[0028] This approach helps reduce the likelihood of terminal devices communicating on specific frequency bands that are restricted in the first region, thus reducing the probability of not meeting the requirements of that region.

[0029] In one possible design, cells operating within a specific frequency band have a lower priority than cells operating outside that specific frequency band. This approach reduces the probability of a terminal device communicating on a specific frequency band where communication is restricted in the first area, thus reducing the probability of not meeting the requirements of that area.

[0030] In one possible design, the cell priority of at least one cell is determined based on the operating frequency band of at least one cell.

[0031] In one possible design, before determining the cell priority of at least one cell, the method further includes: receiving registration information, which is used for the terminal device to register to the network and / or for the USS to authenticate and authorize the terminal device. In this approach, the USS or core network device can determine the cell priority of at least one cell when the terminal device first authenticates (or first joins) in the USS or core network.

[0032] In one possible design, the cell priority information of the at least one cell is carried in the subscription message; or, the cell priority information of the at least one cell is carried in the Radio Resource Control (RRC) reconfiguration message.

[0033] In one possible design, the method further includes sending a first threshold value.

[0034] In one possible design, the method further includes: sending location information of a first region, the location information of the first region being used to indicate the location of the first region.

[0035] In one possible design, the location information of the first region indicates at least one of the following: the latitude and longitude range and / or altitude range of the first region, the location of the center point of the first region, and the location of at least one boundary point of the first region.

[0036] Thirdly, this application also provides a communication device capable of implementing any of the methods provided in the first aspect. This communication device can be implemented in hardware or by hardware executing corresponding software. The hardware or software includes one or more units or modules corresponding to the aforementioned functions.

[0037] In one possible implementation, the communication device includes a processor configured to support the communication device in performing corresponding functions of the terminal device in the methods described above. The communication device may also include a memory coupled to the processor, which stores necessary program instructions and data for the communication device. Optionally, the communication device further includes interface circuitry for supporting communication between the communication device and devices such as access network equipment.

[0038] In one possible implementation, the communication device includes corresponding functional modules, each used to implement the steps in the above method. The functions can be implemented in hardware or by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the functions described above.

[0039] In one possible implementation, the communication device includes a processing unit and a communication unit, which can perform the corresponding functions in the above method examples, as described in the method provided in the first aspect, and will not be repeated here.

[0040] Fourthly, this application also provides a communication device capable of implementing any of the methods provided in the second aspect above. This communication device can be implemented in hardware or by hardware executing corresponding software. The hardware or software includes one or more units or modules corresponding to the aforementioned functions.

[0041] In one possible implementation, the communication device includes a processor configured to support the communication device in performing corresponding functions of the terminal device in the methods described above. The communication device may also include a memory coupled to the processor, which stores necessary program instructions and data for the communication device. Optionally, the communication device further includes interface circuitry for supporting communication between the communication device and devices such as terminal devices.

[0042] In one possible implementation, the communication device includes corresponding functional modules, each used to implement the steps in the above method. The functions can be implemented in hardware or by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the functions described above.

[0043] In one possible implementation, the communication device includes a processing unit and a communication unit, which can perform the corresponding functions in the above method examples, as described in the method provided in the second aspect, and will not be repeated here.

[0044] Fifthly, a computer program product storing instructions is provided, which, when read and executed by a computer, implements the method in any possible implementation of either the first or second aspect.

[0045] In a sixth aspect, a circuit is provided for performing the methods in any possible implementation of the first aspect described above. This circuit may include chip circuitry. Optionally, the circuit may also be coupled to a memory.

[0046] In a seventh aspect, a circuit is provided for performing the methods in any possible implementation of the second aspect described above. This circuit may include chip circuitry. Optionally, the circuit may also be coupled to a memory.

[0047] Eighthly, a chip is provided, comprising a processor, which, when executing a computer program or instructions, implements the methods in any possible implementation of the first aspect. Optionally, the chip may further include a memory, and the chip may be composed of chips or may include chips and other discrete devices.

[0048] A ninth aspect provides a chip including a processor, which, when executing a computer program or instructions, implements the methods in any possible implementation of the second aspect described above. Optionally, the chip may further include a memory, and the chip may be composed of chips or may include chips and other discrete devices.

[0049] In a tenth aspect, a communication device is provided, including a processor that implements the method in any possible implementation of the first aspect by means of logic circuits or by executing computer programs or instructions.

[0050] Eleventhly, a communication device is provided, including a processor that implements the method in any possible implementation of the second aspect by means of logic circuits or by executing computer programs or instructions.

[0051] In a twelfth aspect, a communication apparatus is provided, comprising a unit or module for performing the method in any possible implementation of the first aspect described above.

[0052] In a thirteenth aspect, a communication apparatus is provided, comprising a unit or module for performing the method in any possible implementation of the second aspect described above.

[0053] In a fourteenth aspect, a communication device is provided, including a processor and an interface circuit. The interface circuit is configured to receive signals from other communication devices outside the communication device and transmit them to the processor, or to send signals from the processor to other communication devices outside the communication device. The processor implements the functional modules of the methods in any possible implementation of the first aspect through logic circuits or by executing computer programs or instructions. Optionally, the communication device further includes a memory for storing computer programs or instructions.

[0054] In a fifteenth aspect, a communication device is provided, including a processor and an interface circuit. The interface circuit is configured to receive signals from other communication devices outside the communication device and transmit them to the processor, or to send signals from the processor to other communication devices outside the communication device. The processor implements the functional modules of the methods in any possible implementation of the second aspect by means of logic circuits or by executing computer programs or instructions. Optionally, the communication device further includes a memory for storing computer programs or instructions.

[0055] In a sixteenth aspect, a computer-readable storage medium is provided that stores a computer program or instructions which, when executed by a processor, implement the method in any possible implementation of the first aspect described above.

[0056] In a seventeenth aspect, a computer-readable storage medium is provided that stores a computer program or instructions which, when executed by a processor, implement the method in any possible implementation of the second aspect described above.

[0057] In an eighteenth aspect, embodiments of this application also provide a communication system. The communication system includes: a terminal device; the terminal device is used to implement the methods in the first aspect and any possible implementations thereof; optionally, the communication system may further include an access network device, the access network device being used to communicate with the terminal device. Optionally, the communication system may further include one or more devices selected from a USS and a core network device, the one or more devices selected from the USS and the core network device being used to implement the methods in the second aspect and any possible implementations thereof. Attached Figure Description

[0058] Figure 1 is a schematic diagram of a protocol layer provided in an embodiment of this application;

[0059] Figure 2 is a schematic diagram of an AS security mechanism activation provided in an embodiment of this application;

[0060] Figure 3 is a schematic diagram of an RRC re-establishment process provided in an embodiment of this application;

[0061] Figure 4 is a schematic diagram of the process of a terminal device sending an RA preamble according to an embodiment of this application;

[0062] Figure 5 is a schematic diagram of a drone communication method applicable to an embodiment of this application;

[0063] Figure 6 is a schematic diagram of a communication system provided in an embodiment of this application;

[0064] Figure 7 is a schematic diagram of an open access network provided in an embodiment of this application;

[0065] Figure 8 is a schematic flowchart of a communication method provided in an embodiment of this application;

[0066] Figure 9 is a schematic diagram of a communication process provided in an embodiment of this application;

[0067] Figure 10 is a schematic diagram of another communication process provided in an embodiment of this application;

[0068] Figure 11 is a schematic diagram of the structure of the communication device 1000 provided in an embodiment of this application;

[0069] Figure 12 is a schematic diagram of the structure of the communication device 1100 provided in the embodiment of this application. Detailed Implementation

[0070] To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings. The specific operating methods in the method embodiments can also be applied to the device embodiments or system embodiments.

[0071] The following explanations of some terms used in the embodiments of this application are provided to facilitate understanding by those skilled in the art.

[0072] (1) RRC idle state (RRC_IDLE), RRC connected state (RRC_CONNECTED)

[0073] In the 5G control plane protocol stack, the protocol layers at and below the Radio Resource Control (RRC) layer are generally referred to as the Access Stratum (AS), while the protocol layers above the RRC layer are generally referred to as the Non-Access Stratum (NAS), as shown in Figure 1. Figure 1 illustrates this using the UE as the terminal device, the gNodeB as the access network device, and the AMF as the core network device. Optionally, the AS process requires the participation of both the terminal device and the access network device. The NAS process is handled by both the terminal device and the core network device; the access network device may simply forward the data without processing it.

[0074] Different protocol layers define different layer states, among which the RRC layer states include the RRC idle state (RRC_IDLE) and the RRC connected state (RRC_CONNECTED). When there is a signaling connection between the terminal device and the access network device, the terminal device is in the RRC connected state and can perform data transmission services. Conversely, when the terminal device is in the RRC idle state, it is equivalent to no information exchange between the terminal device and the access network device; there is neither data transmission nor a signaling connection.

[0075] Currently, when a terminal device is in the RRC_CONNECTED state, if a link problem is detected, such as radio link failure (RLF), RRC connection reconfiguration failure, or NR mobility failure, and the AS security mechanism is activated (as shown in Figure 2), the terminal device will attempt to initiate an RRC re-establishment process.

[0076] (2) RRC Re-establishment Process

[0077] Taking the 4-step random access as an example, the RRC re-establishment process includes the following steps, as shown in Figure 3:

[0078] The terminal device first enters a preparation process, performs cell selection, and starts timer T311. T311 is triggered when the RRC re-establishment procedure is executed. If the terminal device finds a suitable cell within the duration of T311, it immediately stops T311. If the terminal device still hasn't found a suitable cell by the time T311 expires, it will enter the RRC_IDLE state.

[0079] Taking the 4-step random access as an example, the RRC re-establishment process mainly includes the following information:

[0080] 1. Random Access Preamble (Msg1).

[0081] The purpose of the RA preamble sent by the terminal device is to inform the access network device of the terminal device's random access request and to estimate the uplink time difference based on the reception of the RA preamble. The terminal device sends the RA preamble via Msg1, and the process of sending the RA preamble by the terminal device is shown in Figure 4.

[0082] Specifically, the terminal device obtains the physical random access channel (PRACH) configuration from the system information block 1 (SIB1) message, and obtains the time-frequency domain position of its RA preamble through the PRACH configuration.

[0083] The terminal device randomly selects a RA preamble. Since each SSB corresponds to a different preamble index, before the terminal device selects a RA preamble, it will first select a Synchronization Signal / Physical Broadcast Channel block (SS / PBCH block, SSB), and then determine the RA preamble according to the SSB. The terminal device can compare the RSRP of all SSBs in the cell with a specified RSRP threshold, and select an SSB greater than the threshold to select the SSB with the best signal. If there is no SSB that meets the requirements, the terminal device can randomly select an SSB.

[0084] 2. RA response, that is, Msg2.

[0085] After receiving the RA preamble of the terminal device, the access network device obtains the uplink timing offset of the terminal device according to the RA preamble. The access network device sends a RA response on the physical downlink shared channel (PDSCH) through Msg2 to indicate that it has received the preamble, and sends the value of the timing advance (TA) to the terminal device through Msg2 for adjusting the transmission timing of the terminal device. In addition, the information carried in the RA response can also include the RA preamble identifier (RA-preamble identifier).

[0086] After the terminal device sends the RA preamble, it can start the RA response time window (RA-ResponseWindow), and continuously detect the physical downlink control channel (PDCCH) within the RA sliding window until the required RA response is obtained on the PDSCH. If the RA response contains a RA-preamble identifier that is the same as that in the RA preamble, the terminal device considers the RA response successful and sends Msg3. If the terminal device never receives a response message in the RA sliding window or the received response verification fails, the terminal device considers that the previous transmission has not been correctly received by the access network device and the RA response fails. At this time, if the RA attempt count of the terminal device is less than the maximum attempt count, a new RA attempt is made, otherwise the RA process fails.

[0087] 3. Msg3

[0088] After Msg2, the terminal device achieves uplink synchronization and can transmit messages on the predetermined physical uplink shared channel (PUSCH). The terminal device sends an RRC Reestablishment Request message (Msg3) to the access network device, which may carry the terminal device's identifier (UE ID), requesting the re-establishment of the RRC connection.

[0089] 4. Msg4

[0090] The access network device replies to the terminal device with an RRC Reestablishment message, namely Msg4. The RRC Reestablishment message carries detailed information on the resource configuration of the signalalling radio bearer (SRB) 1, which is used to establish SRB 1.

[0091] 5. Msg5

[0092] The terminal device configures radio resources according to the SRB1 resource information indicated in the RRCReestablishment message, and then sends an RRC Reestablishment Complete message to the access network device. Upon receiving the RRCReestablishment Complete message, the access network device completes the RRC reestablishment.

[0093] (3) Community Selection

[0094] During cell selection, the terminal device finds a suitable suitable cell (Suitable Cell) for random access. In one implementation, cell selection uses the S-criteria, which states that when the following condition is met: S... rxlev >0 and S qual >0 Performs cell selection. Where S rxlev It is the cell selection receive level value (dB), S qual This refers to the cell selection quality value (dB). Both are measures taken by the terminal equipment when measuring the received signal strength and received quality of a cell. As long as the measured values ​​meet condition S... rxlev >0 and S qual If the value is >0, the selection will succeed and the selection will remain. If the value does not meet the standard or becomes non-compliant due to signal fluctuations, the selection will fail or a reselection process will be initiated.

[0095] In the embodiments of this application, "at least one" refers to one or more, and "more than one" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can represent: a, b, c, a and b, a and c, b and c, or a and b and c, where a, b, and c can be single or multiple.

[0096] Furthermore, unless otherwise stated, the ordinal numbers such as "first" and "second" mentioned in the embodiments of this application are used to distinguish multiple objects and are not used to limit the size, content, order, timing, priority, or importance of multiple objects.

[0097] It should be noted that, in this application, the terms "exemplary" or "for example" are used to indicate that something is being described as an example, illustration, or illustration. Any embodiment or design described as "exemplary" or "for example" in this application should not be construed as being more preferred or advantageous than other embodiments or design solutions. Specifically, the use of terms such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner.

[0098] The terms "comprising" and "having," and any variations thereof, used in the following description of embodiments of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the steps or units listed, but may optionally include other steps or units not listed, or may optionally include other steps or units inherent to such processes, methods, products, or devices.

[0099] It should be noted that in this application, "sending information / data to A" and "sending information / data" simply indicate the direction of information / data transmission, with A being the destination. It does not limit "sending information / data to A" to necessarily being a transmission over the air interface. "Sending information / data to A" includes both direct and indirect transmission to A. Therefore, "sending information / data to A" can also be understood as the processing unit's communication interface "outputting information / data destined for A." Similarly, "sending information / data" can also be understood as "outputting information / data."

[0100] Similarly, "receiving information / data from A" and "receiving information / data" simply indicate the direction of information / data transmission. "From A" means that the source of the information / data is A, including receiving information / data directly from A and receiving information / data indirectly from A. Therefore, "receiving information / data from A" can also be understood as the processing unit's communication interface "inputting information / data from A". Likewise, "receiving information / data" can also be understood as "inputting information / data".

[0101] The preceding text introduced some of the terms used in the embodiments of this application. The following text introduces the technical background of this application.

[0102] The demand for unmanned aerial vehicles (UAVs) is currently growing rapidly. Within the same frequency band of mobile / fixed communication networks (MFCNs), cellular networks can simultaneously provide communication technology support for both UAVs and terrestrial users. Therefore, appropriate spectrum coordination measures are needed to ensure that the communication services of terrestrial users are as unaffected as possible by UAVs, achieving spectrum compatibility. The communication technology support provided by cellular networks for UAVs and terrestrial users can be illustrated in Figure 5.

[0103] When UAVs operate in the air, certain special communication services or communication zones require additional spectrum usage restrictions to ensure that special communication services (such as emergency services) are not interfered with. For example, if a no-transmit zone (NTZ) is defined as a geographical area where UAVs are not allowed to communicate on certain specific frequency bands, when a UAV passes through an NTZ, if its operating frequency is outside the restricted band, the UAV will continue to operate unaffected; however, if its operating frequency is within the restricted band, the original data transmission service should be immediately stopped to ensure that the UAV does not transmit any information within the NTZ, otherwise it will be considered as not meeting the requirements of the area. Therefore, how to prevent UAVs from transmitting data on restricted frequency bands after passing through these areas becomes an urgent problem to be solved.

[0104] Based on this, embodiments of this application provide a communication method and apparatus. By using entry into a first region as the triggering condition for the RRC re-establishment process, the terminal device terminates communication by triggering the RRC re-establishment process after entering the first region. This can, to a certain extent, avoid communication on the restricted frequency bands of the first region after entering it, reducing the probability of not meeting the requirements of that region. Furthermore, this application, by enabling the terminal device to autonomously avoid communication on restricted frequency bands, helps reduce the decision-making risk for the network side, such as operators, and improves the decision-making flexibility of the terminal device.

[0105] The methods and apparatus in the embodiments of this application are based on the same technical concept. Since the methods and apparatus solve problems in similar ways, the implementation of the apparatus and methods can refer to each other, and repeated parts will not be described again.

[0106] This application does not limit the type of communication system used in the embodiments. For example, the communication system can be a communication system related to the 3rd Generation Partnership Project (3GPP). For example, the communication system can be a long-term evolution (LTE), a sixth-generation (5G) mobile communication system (e.g., a new radio (NR) communication system), or it can also be applied to other next-generation mobile communication systems, such as sixth-generation (6G) communication systems, or other similar communication systems. Other similar communication systems may include wireless fidelity (WIFI), vehicle-to-everything (V2X), Internet of Things (IoT) systems, narrowband Internet of Things (NB-IoT) systems, and so on.

[0107] Figure 6 is a schematic diagram of the architecture of the communication system 1000 applied in an embodiment of this application. As shown in Figure 6, the communication system includes a wireless access network 100. The wireless access network 100 may include at least one access network device (110a and / or 110b in Figure 6) and at least one terminal device (at least one of 120a-120j in Figure 6). The terminal device is wirelessly connected to the access network device, and the access network device is wirelessly or wiredly connected to the core network device. Terminal devices and access network devices can be interconnected via wired or wireless means. Figure 6 is only a schematic diagram; the communication system may also include other access network devices, such as wireless relay devices and wireless backhaul devices, which are not shown in Figure 6.

[0108] Access network equipment is a network-side device with wireless transceiver capabilities. Access network equipment can be a device in a radio access network (RAN) that provides wireless communication functions for terminal devices, referred to as RAN equipment. For example, access network equipment can be a base station, an evolved NodeB (eNodeB), a transmission reception point (TRP), a next-generation NodeB (gNB) in a 5G mobile communication system, a next-generation base station in a 6G mobile communication system, a base station in a future mobile communication system, or an access node in a WiFi system; it can also be a module or unit that performs some of the functions of a base station, for example, it can be a central unit (CU) or a distributed unit (DU). The CU here performs the functions of the radio resource control protocol and packet data convergence protocol (PDCP) of the base station, and can also perform the functions of the service data adaptation protocol (SDAP). The DU performs the functions of the radio link control layer and medium access control (MAC) layer of the base station, and can also perform some or all of the physical layer functions. For specific descriptions of the above-mentioned protocol layers, please refer to the relevant technical specifications of the 3rd Generation Partnership Project (3GPP). The access network equipment can be a macro base station (as shown in Figure 1, 110a), a micro base station or an indoor station (as shown in Figure 1, 110b), or a relay node or donor node, etc. The embodiments of this application do not limit the specific technology and specific equipment form used in the access network equipment. The embodiments of this application use a base station as an example for illustration.

[0109] In another possible scenario, multiple RAN nodes collaborate to assist the terminal in achieving wireless access, with different RAN nodes each implementing some of the base station's functions. For example, RAN nodes can be CUs, DUs, CUs (control plane, CP), CUs (user plane, UP), or radio units (RUs). CUs and DUs can be set up separately or included in the same network element, such as a baseband unit (BBU). RUs can be included in radio frequency equipment or radio frequency units, such as remote radio units (RRUs), active antenna units (AAUs), or remote radio heads (RRHs).

[0110] In different systems, CU (or CU-CP and CU-UP), DU, or RU may have different names, but those skilled in the art will understand their meaning. Any of the units among CU (or CU-CP, CU-UP), DU, and RU in this application can be implemented through software modules, hardware modules, or a combination of software and hardware modules. It is understood that in the ORAN system architecture, CU can also be called O-CU, DU can also be called O-DU, CU-CP can also be called O-CU-CP, CU-UP can also be called O-CU-UP, and RU can also be called O-RU. For example, in an open RAN (O-RAN or ORAN) system, the access network equipment can be a combination of an open distributed unit (O-DU) and an open radio unit (O-RU) (or may be called an open radio unit), or it can be a combination of an open centralized unit (O-CU), O-DU, and O-RU. This application does not limit this. For example, in the ORAN system architecture shown in Figure 7, the access network equipment is a combination of O-DU and O-RU. The O-DU has baseband processing capabilities and complete protocol layer functions, primarily responsible for higher-level protocol functions such as data encryption and integrity protection, while also possessing high-level physical layer processing capabilities. The O-RU has low-level physical layer signal processing capabilities, primarily responsible for the transmission and reception of radio frequency signals.

[0111] In this embodiment, the access network device can adopt a CU-DU separation architecture, which can also be called a distributed deployment architecture, or a CU-DU-RU separation architecture. For example, the access network device can logically include one CU and one or more DUs. Each DU can be connected to the CU through an F1 interface, and information exchange between different DUs can be completed based on the forwarding of the CU. The CU and DU can be physically set together or physically separated, without limitation. The CU can support the functions of the radio resource control (RRC) layer protocol, the PDCP layer protocol, and the service data adaptation protocol (SDAP) layer protocol; the DU can support the RLC layer protocol, the MAC layer protocol, and some or all of the physical (PHY) layer functions. For specific descriptions of the above-mentioned protocol layers, please refer to the relevant technical specifications of 3GPP. For another example, the access network device can logically include a CU, a DU, and an RU. The CU and DU can be physically set together or physically separated, without limitation. The CU (Core Unit) supports RRC, PDCP, and SDAP layer protocols; the DU (Distributed Unit) supports RLC and MAC layer protocols, and some PHY layer protocols; the RU (Remote Unit) supports some or all PHY layer protocols. For example, the DU is primarily responsible for higher-level protocol functions such as data encryption and integrity protection, while the RU is primarily responsible for transmitting and receiving radio frequency signals. In this CU-DU-RU separation architecture, the interface between the DU and RU can be called fronthaul, the interface between the CU and DU can be called midhaul, and the interface between the CU and core network equipment can be called backhaul.

[0112] A terminal device is a user-side device with wireless transceiver capabilities. Terminal devices can also be called user equipment (UE), mobile station, mobile terminal, etc. Terminal devices can be widely used in various scenarios, such as device-to-device (D2D), vehicle-to-everything (V2X) communication, machine-type communication (MTC), Internet of Things (IoT), virtual reality, augmented reality, industrial control, autonomous driving, telemedicine, smart grids, smart furniture, smart offices, smart wearables, smart transportation, smart cities, etc. Terminal devices can be mobile phones, tablets, computers with wireless transceiver capabilities, wearable devices, vehicles, drones, helicopters, airplanes, ships, robots, robotic arms, smart home devices, etc. The embodiments of this application do not limit the specific technologies or device forms used in the terminal devices. The embodiments of this application use a terminal device as the execution subject for illustration.

[0113] Access network equipment and terminal equipment can be fixed or mobile. They can be deployed on land, including indoors or outdoors, handheld or vehicle-mounted; they can also be deployed on water; and they can be deployed in the air on aircraft, balloons, and satellites. The embodiments of this application do not limit the application scenarios of the access network equipment and terminal equipment.

[0114] The roles of access network devices and terminal devices can be relative. For example, the helicopter or drone 120i in Figure 6 can be configured as a mobile access network device. For terminal devices 120j that access the wireless access network 100 via 120i, terminal device 120i is an access network device; however, for access network device 110a, 120i is a terminal device. That is, 110a and 120i communicate via a wireless air interface protocol. Of course, 110a and 120i can also communicate via an interface protocol between access network devices. In this case, relative to 110a, 120i is also an access network device. Therefore, both access network devices and terminal devices can be collectively referred to as communication devices. 110a and 110b in Figure 6 can be called communication devices with access network device functions, and 120a-120j in Figure 6 can be called communication devices with terminal device functions.

[0115] In the embodiments of this application, the functions of the access network device can be executed by modules (such as chips) within the access network device, or by a control subsystem that includes the functions of the access network device. This control subsystem, including the functions of the access network device, can be a control center in the aforementioned application scenarios such as smart grids, industrial control, intelligent transportation, and smart cities. Similarly, the functions of the terminal device can be executed by modules (such as chips or modems) within the terminal device, or by a device that includes the functions of the terminal device.

[0116] The network architecture and business scenarios described in the embodiments of this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided in the embodiments of this application. As those skilled in the art will know, with the evolution of network architecture and the emergence of new business scenarios, the technical solutions provided in the embodiments of this application are also applicable to similar technical problems.

[0117] In the embodiments of this application, "when," "if," and "if" all refer to the device taking corresponding actions under certain objective circumstances, and are not time-limited, nor do they require the device to perform a judgment action, nor do they imply any other limitations. Unless otherwise specified, "if" and "if" can be substituted, and "when" and "in the case of" can be substituted. "When" and "if" / "if" can be substituted.

[0118] The technical solutions in the embodiments of this application will now be described with reference to the accompanying drawings.

[0119] The communication method provided in this application embodiment can be executed by a terminal device. The steps executed by the terminal device can be implemented by the terminal device itself, or by components in the terminal device (such as chips (e.g., baseband chips, or other processing units or processor modules).

[0120] For example, the terminal device in this application can be a mobile terminal, such as a UAV.

[0121] Figure 8 shows a flowchart of a communication method provided in an embodiment of this application. The method includes:

[0122] S301, the terminal device has confirmed that it has entered the first area.

[0123] The first region is an area where communication on the first frequency band is prohibited. Alternatively, the first region can be a geographical area, meaning it is an area where communication on the first frequency band is not permitted. For example, the first region is a no-transmit zone (NTZ). The first frequency band exists within the first region, and terminal equipment (such as UAVs or other airborne terminal equipment) is not allowed to transmit or receive any signals on the first frequency band when passing through this region.

[0124] For example, the first frequency band may include one or more frequency bands. The first frequency band may also be referred to as a specific frequency band, a restricted frequency band, etc.

[0125] As an example, the phrase "determining to enter the first region" can be described as determining that a first condition is met, where the first condition is related to the first region. For example, the first condition may include entering the first region, or about to enter the first region.

[0126] Alternatively, the phrase "confirming entry into the first zone" can also be understood as confirming that one is about to enter the first zone.

[0127] Alternatively, the phrase "determined to enter the first area" can also be understood as "determined to meet the second condition," which is that communication is not possible on the first frequency band, etc.

[0128] In one possible implementation, the aforementioned triggering conditions, such as the first condition and the second condition, can be defined by a protocol, while one or more of the information related to the first condition, the second condition, such as the location information of the region (e.g., the first region) and the information of the specific frequency band (e.g., the first frequency band), can be configured by the USS, core network equipment, etc. For example, the location information of the first region may include, but is not limited to, one or more of the following: the location information of at least one boundary point, the location information of the center point, a latitude and longitude range, and an altitude range. The aforementioned location information may include latitude and longitude information and / or altitude information.

[0129] In one possible implementation, information such as the location information of the first area and the information of the first frequency band can be sent to the terminal device during the initial registration (or initial network access) process of the terminal device in the USS or core network.

[0130] For example, after receiving the registration information of the terminal device, the USS can send information such as the location information of the first region and the information of the first frequency band to the terminal device. This registration information is used for the terminal device to register with the USS, or for the terminal device to authenticate with the USS. For instance, the USS sends a subscription message to the terminal device through the UAS, which carries information such as the location information of the first region and the information of the first frequency band. Optionally, this subscription message can be a subscription message in the UAV authorization / authentication (UUAA) process.

[0131] Alternatively, after receiving the registration information from the terminal device, the core network device can send the terminal device location information of the first area, information of the first frequency band, and other information. This registration information is used for the terminal device to register with the core network. For example, after receiving the registration information from the terminal device, the core network device can send the access network device location information of the first area, information of the first frequency band, and other information. The access network device then sends these same information to the terminal device via an RRC reconfiguration message.

[0132] For example, one application scenario of the first condition is when a terminal device passes through a first area during its movement, where communication on the first frequency band is not allowed within the first area. For instance, this could be a drone's flight path passing through the first area. It should be noted that the above scenarios are merely examples, and this application does not limit the specific application scenario of the first condition. The above first condition can be applied wherever there is a scenario where communication is restricted in a specific area.

[0133] One application scenario for the second condition is that the terminal device cannot communicate on the first frequency band in certain situations. For example, the first frequency band may be allocated to other devices or specific services; the first frequency band may be set to disallow communication by a certain type of device, and the terminal device belongs to that type; or the first frequency band may be set to disallow communication by a certain type of device in certain areas and / or during certain time periods, and the terminal device belongs to that type of device and has moved to that area and / or is in that time period. Therefore, the terminal device cannot communicate on the first frequency band in these scenarios. It should be noted that the above scenarios are merely examples, and this application does not limit the specific application scenario of the second condition. The second condition can be applied wherever there is a scenario where communication on a specific frequency band is not permitted.

[0134] To facilitate understanding of the scheme, the following example, which includes determining entry into the first area, will be used to illustrate how the terminal device determines that the first condition is met.

[0135] As an alternative approach, the terminal device can determine whether the first condition is met based on the distance between the first area and the terminal device; that is, it can determine whether to enter the first area based on the distance between the first area and the terminal device. Alternatively, it can be described as determining whether the condition for triggering RRC re-establishment is met based on the distance between the first area and the terminal device. In one possible approach, the terminal device continuously calculates the distance between its current location and the first area during movement.

[0136] For example, if the distance between the first area and the terminal device is less than or equal to a first threshold, then entering the first area is determined. Alternatively, it can be described as: if the distance between the first area and the terminal device is less than or equal to a first threshold, then the first condition is determined to be met. Or, it can also be described as: if the distance between the first area and the terminal device is less than or equal to a first threshold, then the condition for triggering RRC re-establishment is determined to be met.

[0137] Optionally, when determining entry into the first area based on the distance between the terminal device and the first area, the terminal device may consider the direction of movement of the terminal device and / or the position of the terminal device.

[0138] For example, if the distance between the first area and the terminal device is less than or equal to a first threshold, and the terminal device is moving towards the first area, then it is determined that the device has entered the first area. Alternatively, it can be described as follows: if the distance between the first area and the terminal device is less than or equal to the first threshold, then it is determined that the first condition is met. Or, it can also be described as follows: if the distance between the first area and the terminal device is less than or equal to the first threshold, and the terminal device is moving towards the first area, then it is determined that the condition for triggering RRC re-establishment is met.

[0139] For example, if the distance between the first area and the terminal device is less than or equal to a first threshold, and the terminal device is outside the first area, then it is determined that the user has entered the first area. Alternatively, it can be described as follows: if the distance between the first area and the terminal device is less than or equal to a first threshold, and the terminal device is outside the first area, then it is determined that the first condition is met. Or, it can also be described as follows: if the distance between the first area and the terminal device is less than or equal to a first threshold, and the terminal device is outside the first area, then it is determined that the condition for triggering RRC re-establishment is met.

[0140] For example, if the distance between the first area and the terminal device is less than or equal to a first threshold, the terminal device moves towards the first area, and is outside the first area, then it is determined that the device has entered the first area. Alternatively, it can be described as follows: if the distance between the first area and the terminal device is less than or equal to a first threshold, the terminal device moves towards the first area, and is outside the first area, then it is determined that the first condition is met. Or, it can also be described as follows: if the distance between the first area and the terminal device is less than or equal to a first threshold, the terminal device moves towards the first area, and is outside the first area, then it is determined that the condition for triggering RRC re-establishment is met.

[0141] The first threshold can be the absolute value of the minimum distance between the terminal device and the first area, outside of which the terminal device can communicate normally with the access network equipment. Optionally, the first threshold can be determined by the terminal device, for example, the terminal device can determine the first threshold based on its speed. Alternatively, the first threshold can also be indicated by the USS, core network equipment, etc.

[0142] As an optional approach, the distance between the first region and the terminal device can be determined based on at least one of the following: the location of the first region, and the location of the terminal device. For example, the location of the first region can be the latitude and longitude range and / or altitude range of the first region, or the location information of at least one boundary point of the first region, or the location information of the center point of the first region, etc.

[0143] Taking the latitude and longitude range and / or altitude range of the first region as an example, the terminal device can determine at least one distance between the terminal device and the first region based on the latitude and longitude range and / or altitude range of the first region, and determine the minimum distance among the at least one distance as the distance between the first region and the terminal device.

[0144] Taking the location information of at least one boundary point of the first region as an example, the terminal device can determine at least one distance between the first region and the terminal device based on the location of at least one boundary point of the first region and the location of the terminal device; the minimum distance among the at least one distance is determined as the distance between the first region and the terminal device.

[0145] Taking the location information of the center point of the first area as an example, the terminal device can determine the distance between the first area and the terminal device based on the location of the center point of the first area and the location of the terminal device.

[0146] S302, the terminal device starts the first timer.

[0147] The first timer is a timer related to cell selection. For example, the first timer is used to control the duration required for the cell selection process. Alternatively, it can be described as a timer that starts after triggering RRC re-establishment. Or, the first timer can also be understood as the waiting time for the terminal device to enter the RRC idle (RRC_IDLE) state after triggering the RRC re-establishment process, or the maximum duration between the terminal device triggering the RRC reconstruction process and selecting a cell.

[0148] In one exemplary embodiment, the first timer may be a T311 timer.

[0149] In this application, the first timer is triggered by meeting a first condition (i.e., determining that the device has entered the first region). In other words, the terminal device starts the first timer after determining that the first condition is met. Alternatively, this method can also be described as the terminal device triggering an RRC re-establishment process when it determines that the first condition is met. The triggering of the RRC re-establishment process is a condition for starting the first timer. Therefore, when the terminal device triggers the RRC re-establishment process when it determines that the first condition is met, it means that the first timer is started.

[0150] Understandably, S301 and S302 can be interpreted as the terminal device triggering an RRC re-establishment process (or starting the first timer) when it cannot communicate on the first frequency band (e.g., when the first condition or the second condition is met). Similarly, if there are requirements or restrictions on communication in other scenarios, these scenarios can also be used as conditions to trigger RRC re-establishment (or to start the first timer).

[0151] This application uses entering the first region as a trigger condition for the RRC re-establishment process. This allows the terminal device to terminate communication upon entering the first region by triggering the RRC re-establishment process, thereby avoiding communication on specific frequency bands within the first region and reducing the probability of not meeting the region's requirements. Furthermore, this application enables the terminal device to autonomously avoid communication on specific frequency bands, which helps reduce decision-making risks for network sides, such as operators, and improves the decision-making flexibility of the terminal device.

[0152] Optionally, the terminal device may suspend ongoing communication services when it determines that it has entered the first area.

[0153] S303, the terminal device performs cell selection during the first timer period.

[0154] In one possible implementation, the terminal device can select a cell based on at least one of the following: a first frequency band, or cell priority; where cell priority refers to the priority of cell selection, and the terminal device can prioritize cells with higher cell priorities during cell selection. This approach, by considering specific frequency bands and cell priorities associated with those specific frequency bands, can reduce the probability of the terminal device communicating on specific frequency bands with limited communication in the first area, thereby reducing the likelihood of not meeting the requirements of that area.

[0155] In this application, the cell priority of a cell whose operating frequency band (or center frequency or operating frequency, etc.) belongs to the first frequency band is lower than the cell priority of a cell whose operating frequency band does not belong to the first frequency band. The cell priority can be set by the USS or core network equipment, etc. For example, the USS or core network equipment can send cell priority information of at least one cell to the terminal equipment.

[0156] Optionally, before sending information about the cell priority of at least one cell to the terminal device, the USS or core network equipment may determine the cell priority of the at least one cell. For example, the cell priority of the at least one cell may be determined based on the operating frequency band of the at least one cell. The cell priority of a cell whose operating frequency band (or center frequency or operating frequency, etc.) belongs to the first frequency band is lower than the cell priority of a cell whose operating frequency band does not belong to the first frequency band.

[0157] In one possible implementation, the USS or core network equipment can determine the cell priority of at least one cell after receiving the registration information of the terminal equipment.

[0158] Optionally, the cell priority information of the at least one cell can be sent to the terminal device during the initial registration (or initial network access) process of the terminal device in the USS or core network.

[0159] For example, after receiving the registration information of the terminal device, the USS can send the cell priority information of at least one cell to the terminal device. This registration information is used for the terminal device to register with the USS, or for the terminal device to authenticate with the USS. For instance, the USS sends a subscription message to the terminal device through the UAS, and this subscription message carries the cell priority information of the at least one cell. Optionally, this subscription message can be a subscription message in the UUAA process.

[0160] Alternatively, after receiving the registration information from the terminal device, the core network device may send the cell priority information of at least one cell to the terminal device. This registration information is used for the terminal device to register with the core network. For example, after receiving the registration information from the terminal device, the core network device may send the cell priority information of at least one cell to the access network device, and the access network device may send the cell priority information of at least one cell to the terminal device via an RRC reconfiguration message.

[0161] In one exemplary embodiment, the terminal device may perform cell selection in the manner described above during the RRC re-establishment process triggered by entering the first area.

[0162] Below are three examples of neighborhood selection.

[0163] Example 1: The terminal device can perform cell search and, after selecting a cell, determine whether to initiate random access to that cell based on the aforementioned first frequency band. For example, the cell can be selected as follows: During cell search, the terminal device can select a cell based on cell priority, prioritizing cells whose operating frequency band is outside the first frequency band. For instance, suppose there are three cells, cells 1 to 3. Cells 1 and 2 operate in frequencies outside the first frequency band, while cell 3 operates in the first frequency band. Cells 1 and 2 have a priority of 1, and cell 3 has a priority of 2. A lower priority value indicates a higher priority. During cell search, if cells 1 to 3 all meet the selection criteria (e.g., satisfying the S criterion), the terminal device prioritizes cell 1 or cell 2. If cells 1 and 2 do not meet the selection criteria (e.g., not satisfying the S criterion or other reasons), but cell 3 meets the selection criteria, the terminal device selects cell 3.

[0164] Optionally, the above-mentioned cells satisfy the S criterion.

[0165] For example, suppose a terminal device selects the first cell during cell search. After selecting the first cell, the terminal device can determine whether to initiate random access to that cell based on the aforementioned first frequency band. If the operating frequency band of the first cell is not part of the first frequency band, the terminal device can initiate random access to that cell and stop the first timer. If the operating frequency band of the first cell is part of the first frequency band, the terminal device cannot initiate random access to that cell and continues timing the first timer; alternatively, it can be described as waiting for the first timer to time out. Through this design, on the one hand, it can avoid the terminal device communicating on specific frequency bands with limited communication in the first area to a certain extent, reducing the probability of not meeting the requirements of that area; on the other hand, it can enable the terminal device to restore communication in a timely manner, reducing the duration of communication interruption.

[0166] If the operating frequency band of the first cell selected by the terminal device belongs to the first frequency band, there may be two situations during the time period when the terminal device is waiting for the first timer to expire. One situation is that it leaves the first area, such as in a scenario where the coverage area of ​​the first area is relatively small or the terminal device moves at a relatively fast speed. The other situation is that it does not leave the first area.

[0167] For situations where a terminal device leaves the first area while waiting for the first timer to expire, the terminal device can reselect a cell before the first timer expires. This method provides a mechanism for reselecting a cell after leaving the first area, allowing the terminal device to promptly select a suitable cell to resume communication without waiting for the first timer to expire. This helps reduce communication interruption time and improves user experience.

[0168] For situations where the terminal device does not leave the first area during the waiting period for the first timer to expire, three optional solutions are introduced here.

[0169] Option 1: The terminal device can stop cell selection and enter the RRC idle state after the first timer expires.

[0170] After the first timer expires, the terminal device can remain in the RRC idle state while still within the first area. Optionally, during this period, even if a communication service meets the conditions for triggering entry into the RRC connected state, the terminal device can suspend that communication service and remain in the RRC idle state. This method, by keeping the terminal device in the RRC idle state, avoids the terminal device communicating on specific frequency bands where communication is restricted in the first area, reducing the probability of not meeting the requirements of that area.

[0171] After the first timer expires, when the terminal device leaves the first area, it can establish an RRC connection with the access network device. For example, the terminal device can trigger the establishment of an RRC connection with the access network device by resuming the first communication service. The first communication service is the communication service that was suspended before the first timer was started. This method allows the terminal device to resume communication promptly, reducing the duration of communication interruptions and improving the user experience.

[0172] Option 2 allows the terminal device to select other cells found in the cell search and determine whether to initiate random access to that cell based on the aforementioned first frequency band. For example, events triggering the termination of this option include at least one of the following: selecting a cell whose operating frequency band does not belong to the first frequency band for random access, the first timer expiring, or the number of cell selections (or the number of cells) reaching a threshold. This method allows the terminal device to select other cells, thereby enabling the terminal device to restore communication promptly and reducing the duration of communication interruptions.

[0173] Optionally, after the first timer expires and the terminal device leaves the first area, the terminal device can establish an RRC connection with the access network device. For example, the terminal device can trigger the establishment of an RRC connection with the access network device by resuming the first communication service. The first communication service is the communication service that was suspended before the first timer was started. This method allows the terminal device to resume communication promptly, which helps reduce the duration of communication interruptions and improves the user experience.

[0174] Option 3 allows the terminal device to reselect a cell and, upon selection, determine whether to initiate random access to that cell based on the aforementioned first frequency band. For example, events triggering the termination of this option include at least one of the following: selecting a cell whose operating frequency band does not belong to the first frequency band for random access, the first timer expiring, or the number of cell selection attempts reaching a threshold. This method allows the terminal device to promptly restore communication by selecting another cell, reducing the duration of communication interruptions.

[0175] Optionally, after the first timer expires and the terminal device leaves the first area, the terminal device can establish an RRC connection with the access network device. For example, the terminal device can trigger the establishment of an RRC connection with the access network device by resuming the first communication service. The first communication service is the communication service that was suspended before the first timer was started. This method allows the terminal device to resume communication promptly, which helps reduce the duration of communication interruptions and improves the user experience.

[0176] In one exemplary description, the phrase "leaving the first region" may refer to having already left the first region.

[0177] The following describes how a terminal device determines whether it is leaving the first area.

[0178] As an alternative approach, the terminal device can determine whether to leave the first area based on the distance between the terminal device and the first area. Alternatively, it can be described as determining whether the conditions for triggering RRC re-establishment are met based on the distance between the terminal device and the first area. In one implementation, the terminal device continuously calculates the distance between its current location and the first area during movement.

[0179] For example, if the distance between the first area and the terminal device is greater than or equal to a first threshold, then it is determined that the user has left the first area. Alternatively, it can be described as follows: if the distance between the first area and the terminal device is greater than or equal to a first threshold, then it is determined that the condition for triggering RRC re-establishment is met.

[0180] Optionally, when determining whether to leave the first area based on the distance between the first area and the terminal device, the terminal device may consider the direction of movement of the terminal device and / or the position of the terminal device.

[0181] For example, if the distance between the first area and the terminal device is greater than or equal to a first threshold, and the terminal device is moving away from the first area, then it is determined that the device has left the first area. Alternatively, it can be described as follows: if the distance between the first area and the terminal device is greater than or equal to a first threshold, and the terminal device is moving away from the first area, then it is determined that the condition for triggering RRC re-establishment is met.

[0182] For example, if the distance between the first area and the terminal device is greater than or equal to a first threshold, and the terminal device is outside the first area, then it is determined that the device has left the first area. Alternatively, it can be described as follows: if the distance between the first area and the terminal device is greater than or equal to a first threshold, and the terminal device is outside the first area, then it is determined that the conditions for triggering RRC re-establishment are met.

[0183] For example, if the distance between the first area and the terminal device is greater than or equal to a first threshold, the terminal device moves away from the first area, and the terminal device is outside the first area, then it is determined that the device has left the first area. Alternatively, it can be described as follows: if the distance between the first area and the terminal device is greater than or equal to a first threshold, the terminal device moves away from the first area, and the terminal device is outside the first area, then it is determined that the conditions for triggering RRC re-establishment are met.

[0184] The first threshold can be the absolute value of the minimum distance between the terminal device and the first area, outside of which the terminal device can communicate normally with the access network equipment. Optionally, the first threshold can be determined by the terminal device, for example, the terminal device can determine the first threshold based on its speed. Alternatively, the first threshold can also be indicated by the USS, core network equipment, etc.

[0185] As an optional approach, the distance between the first region and the terminal device can be determined based on at least one of the following: the location of the first region, and the location of the terminal device. For example, the location of the first region can be the latitude and longitude range and / or altitude range of the first region, or the location information of at least one boundary point of the first region, or the location information of the center point of the first region, etc.

[0186] Taking the latitude and longitude range and / or altitude range of the first region as an example, the terminal device can determine at least one distance between the terminal device and the first region based on the latitude and longitude range and / or altitude range of the first region, and determine the minimum distance among the at least one distance as the distance between the first region and the terminal device.

[0187] Taking the location information of at least one boundary point of the first region as an example, the terminal device can determine at least one distance between the first region and the terminal device based on the location of at least one boundary point of the first region and the location of the terminal device; the minimum distance among the at least one distance is determined as the distance between the first region and the terminal device.

[0188] Taking the location information of the center point of the first area as an example, the terminal device can determine the distance between the first area and the terminal device based on the location of the center point of the first area and the location of the terminal device.

[0189] To facilitate understanding of the scheme, the following example uses T311 as the first timer and describes the communication process of the terminal device introduced in Example 1 in conjunction with the above scheme 1.

[0190] As shown in Figure 9, the communication process includes:

[0191] S901, when the terminal device enters the first area, it triggers the RRC re-establishment process.

[0192] The specific method by which the terminal device determines its entry into the first area can be found in the relevant description in S301 above. For example, it may determine its entry into the first area based on the distance between the terminal device and the first area. This will not be elaborated further here.

[0193] The triggering of the RRC re-establishment process is a condition for the T311 to start. Therefore, when the terminal device triggers the RRC re-establishment process, it means that the T311 is started.

[0194] This application sets a new trigger condition for RRC re-establishment (i.e., entering the first zone). When the terminal device determines that it has entered the first zone, it triggers the RRC re-establishment process. Optionally, if an ongoing communication service, such as a data transmission service, is in progress, the communication service can be suspended.

[0195] It should be noted that in the process described in Figure 9, "when entering the first area" can be understood as when the first condition is met; here, "entering the first area" is just one example of the first condition. Similarly, if the second condition is used as the condition for triggering the RRC reconstruction process, S901 can be replaced by the terminal device triggering the RRC re-establishment process when the second condition is met.

[0196] S902, the terminal device selects a cell.

[0197] Assuming the terminal device selects the first cell, optionally, the first cell satisfies the S criterion.

[0198] Optionally, after selecting the first cell, the terminal device can add a condition to determine whether the operating frequency band of the selected first cell belongs to the first frequency band. Therefore, there are two possible scenarios for the first cell: either the operating frequency band of the first cell does not belong to the first frequency band, or the operating frequency band of the first cell does belong to the first frequency band. For the scenario where the operating frequency band of the first cell does not belong to the first frequency band, step S903 can be executed. For the scenario where the operating frequency band of the first cell belongs to the first frequency band, step S904 can be executed.

[0199] S903, if the operating frequency band of the first cell does not belong to the first frequency band, the terminal device stops T311 timing and initiates random access to the first cell.

[0200] S904, if the operating frequency band of the first cell belongs to the first frequency band, the terminal device waits for T311 timeout.

[0201] If the operating frequency band of the first cell belongs to the first frequency band, then the first cell is not suitable for the terminal device to camp on, so the T311 termination condition is not met, and the terminal device waits for the T311 timeout.

[0202] During the timeout period of the terminal device waiting for T311, two scenarios are possible: leaving the first area during the first timer timeout period (e.g., in scenarios where the coverage area of ​​the first area is small or the terminal device moves quickly), and not leaving the first area during the first timer timeout period. For the scenario where the terminal device leaves the first area during the first timer timeout period, S905 can be executed. For the scenario where the terminal device does not leave the first area during the first timer timeout period, S906 can be executed.

[0203] The specific method by which the terminal device determines to leave the first area can be found in the previous descriptions. For example, it may determine to leave the first area based on the distance between the terminal device and the first area. This will not be elaborated on here.

[0204] S905 If the terminal device leaves the first area during the time period of waiting for the first timer to expire, it can reselect the cell before the T311 timeout.

[0205] If the terminal device selects a suitable cell before the T311 timeout, it can initiate random access to that cell. If the terminal device does not select a suitable cell before the T311 timeout, it can enter the RRC idle state after the T311 timeout.

[0206] Optionally, since the terminal device has left the first area, after the terminal device reselects a suitable cell, it may not need to determine whether to initiate random access to that cell based on the aforementioned first frequency band. That is, the terminal device initiates random access to that cell after reselecting a suitable cell.

[0207] S906, if the terminal device does not leave the first area within the time period of waiting for the first timer to expire, it enters the RRC idle state after waiting for T311 to expire.

[0208] Optionally, even if a communication service meets the conditions for triggering the terminal device to enter the connected state before the terminal device leaves the first area, the communication service can be suspended, so that the terminal device remains in the RRC idle state.

[0209] Optionally, S907 can be executed after S906.

[0210] S907: After leaving the first area, the terminal device can establish an RRC connection with the access network device.

[0211] For example, the terminal device can trigger the establishment of an RRC connection with the access network device by restoring the first communication service. The first communication service is the communication service that was suspended before the first timer was started.

[0212] It should be noted that steps S903 to 907 above are optional.

[0213] Example 2: During cell search, the terminal device can randomly select a cell for access based on cell priority, prioritizing cells whose operating frequency band is outside the first frequency band. Cell priority refers to the priority of cell selection; the terminal device can prioritize cells with higher priority. In this application, the cell priority of a cell whose operating frequency band (or center frequency point, etc.) belongs to the first frequency band is lower than the cell priority of a cell whose operating frequency band does not belong to the first frequency band.

[0214] Cell priority can be set by USS or core network equipment, for example, USS or core network equipment can send cell priority information of at least one cell to the terminal equipment.

[0215] Optionally, before sending information about the cell priority of at least one cell to the terminal device, the USS or core network equipment may determine the cell priority of the at least one cell. For example, the cell priority of the at least one cell may be determined based on the operating frequency band of the at least one cell. The cell priority of a cell whose operating frequency band (or center frequency or operating frequency, etc.) belongs to the first frequency band is lower than the cell priority of a cell whose operating frequency band does not belong to the first frequency band.

[0216] In one possible implementation, the USS or core network equipment can determine the cell priority of at least one cell after receiving the registration information of the terminal equipment.

[0217] Optionally, the cell priority information of the at least one cell can be sent to the terminal device during the initial registration (or initial network access) process of the terminal device in the USS or core network.

[0218] For example, after receiving the registration information of the terminal device, the USS can send the cell priority information of at least one cell to the terminal device. This registration information is used for the terminal device to register with the USS, or for the terminal device to authenticate with the USS. For instance, the USS sends a subscription message to the terminal device through the UAS, and this subscription message carries the cell priority information of the at least one cell. Optionally, this subscription message can be a subscription message in the UUAA process.

[0219] Alternatively, after receiving the registration information from the terminal device, the core network device may send the cell priority information of at least one cell to the terminal device. This registration information is used for the terminal device to register with the core network. For example, after receiving the registration information from the terminal device, the core network device may send the cell priority information of at least one cell to the access network device, and the access network device may send the cell priority information of at least one cell to the terminal device via an RRC reconfiguration message.

[0220] For example, suppose there are three cells, designated cells 1 to 3. Cells 1 and 2 operate in frequencies outside the first frequency band, while cell 3 operates in the first frequency band. Cells 1 and 2 have a priority of 1, and cell 3 has a priority of 2. A lower priority value indicates a higher priority. When a terminal device searches for a cell, if all three cells meet the selection criteria (e.g., satisfying the S criterion), the terminal device will preferentially select cell 1 or cell 2. If cells 1 and 2 do not meet the selection criteria (e.g., not meeting the S criterion or other reasons), but cell 3 meets the selection criteria, the terminal device will select cell 3.

[0221] Optionally, the above-mentioned cells satisfy the S criterion.

[0222] Optionally, after selecting a cell, the terminal device can determine whether to initiate random access to that cell based on the first frequency band mentioned above.

[0223] For example, suppose a terminal device selects the first cell during cell search. After selecting the first cell, the terminal device can determine whether to initiate random access to that cell based on the aforementioned first frequency band. If the operating frequency band of the first cell is not part of the first frequency band, the terminal device can initiate random access to that cell and stop the first timer. If the operating frequency band of the first cell is part of the first frequency band, the terminal device cannot initiate random access to that cell and continues counting down the first timer; alternatively, it can be described as waiting for the first timer to time out.

[0224] If the operating frequency band of the first cell selected by the terminal device belongs to the first frequency band, there may be two situations during the time period when the terminal device is waiting for the first timer to expire. One situation is that it leaves the first area, such as in a scenario where the coverage area of ​​the first area is relatively small or the terminal device moves at a relatively fast speed. The other situation is that it does not leave the first area.

[0225] For situations where a terminal device leaves the first area while waiting for the first timer to expire, the terminal device can reselect a cell before the first timer expires. This method provides a mechanism for reselecting a cell after leaving the first area, allowing the terminal device to promptly select a suitable cell to resume communication without waiting for the first timer to expire. This helps reduce communication interruption time and improves user experience.

[0226] For cases where the terminal device does not leave the first area during the waiting period for the first timer to expire, please refer to Scheme 1 to Scheme 3 in Example 1 above, which will not be elaborated here.

[0227] The specific method by which the terminal device determines to leave the first area can be found in the relevant description in Example 1 above. For example, it may determine to leave the first area based on the distance between the terminal device and the first area. This will not be elaborated here.

[0228] To facilitate understanding of the scheme, the following example uses T311 as the first timer and describes the communication process of the terminal device described in Example 2 in conjunction with the above scheme 1.

[0229] As shown in Figure 10, the communication process includes:

[0230] S1001, When the terminal device enters the first area, it triggers the RRC re-establishment process.

[0231] The specific method by which the terminal device determines its entry into the first area can be found in the relevant description in S301 above. For example, it may determine its entry into the first area based on the distance between the terminal device and the first area. This will not be elaborated further here.

[0232] The triggering of the RRC re-establishment process is a condition for the T311 to start. Therefore, when the terminal device triggers the RRC re-establishment process, it means that the T311 is started.

[0233] This application sets a new trigger condition for RRC re-establishment (i.e., entering the first zone). When the terminal device determines that it has entered the first zone, it triggers the RRC re-establishment process. Optionally, if an ongoing communication service, such as a data transmission service, is in progress, the communication service can be suspended.

[0234] It should be noted that in the process described in Figure 10, "when entering the first area" can be understood as when the first condition is met; here, "entering the first area" is just one example of the first condition. Similarly, if the second condition is used as the condition for triggering the RRC reconstruction process, S901 can be replaced by the terminal device triggering the RRC re-establishment process when the second condition is met.

[0235] S1002, the terminal device selects cells based on cell priority, prioritizing cells with higher cell priority.

[0236] Optionally, the USS or core network equipment can send the cell priority value of at least one cell to the terminal equipment.

[0237] Assuming the terminal device selects the first cell, optionally, the first cell satisfies the S criterion.

[0238] Optionally, after selecting the first cell, the terminal device can add a condition to determine whether the operating frequency band of the selected first cell belongs to the first frequency band. Therefore, there are two possible scenarios for the first cell: either the operating frequency band of the first cell does not belong to the first frequency band, or the operating frequency band of the first cell does belong to the first frequency band. For the scenario where the operating frequency band of the first cell does not belong to the first frequency band, step S1003 can be executed. For the scenario where the operating frequency band of the first cell belongs to the first frequency band, step S1004 can be executed.

[0239] S1003, if the operating frequency band of the first cell does not belong to the first frequency band, the terminal device stops T311 timing and initiates random access to the first cell.

[0240] S1004, if the operating frequency band of the first cell belongs to the first frequency band, the terminal device waits for T311 timeout.

[0241] If the operating frequency band of the first cell belongs to the first frequency band, then the first cell is not suitable for the terminal device to camp on, so the T311 termination condition is not met, and the terminal device waits for the T311 timeout.

[0242] During the timeout period of the terminal device waiting for T311, two scenarios are possible: leaving the first area during the first timer timeout period (e.g., in scenarios where the coverage area of ​​the first area is small or the terminal device moves quickly), and not leaving the first area during the first timer timeout period. For the scenario where the terminal device leaves the first area during the first timer timeout period, S1005 can be executed. For the scenario where the terminal device does not leave the first area during the first timer timeout period, S1006 can be executed.

[0243] The specific method by which the terminal device determines to leave the first area can be found in the previous descriptions. For example, it may determine to leave the first area based on the distance between the terminal device and the first area. This will not be elaborated on here.

[0244] S1005 If the terminal device leaves the first area during the time period of waiting for the first timer to expire, it can reselect the cell before T311 expires.

[0245] If the terminal device selects a suitable cell before the T311 timeout, it can initiate random access to that cell. If the terminal device does not select a suitable cell before the T311 timeout, it can enter the RRC idle state after the T311 timeout.

[0246] Optionally, since the terminal device has left the first area, after the terminal device reselects a suitable cell, it may not need to determine whether to initiate random access to that cell based on the aforementioned first frequency band. That is, the terminal device initiates random access to that cell after reselecting a suitable cell.

[0247] S1006, if the terminal device does not leave the first area within the time period of waiting for the first timer to expire, it enters the RRC idle state after waiting for T311 to expire.

[0248] Optionally, even if a communication service meets the conditions for triggering the terminal device to enter the connected state before the terminal device leaves the first area, the communication service can be suspended, so that the terminal device remains in the RRC idle state.

[0249] Optionally, S1007 can be executed after S1006.

[0250] S1007, After leaving the first area, the terminal device can establish an RRC connection with the access network device.

[0251] For example, the terminal device can trigger the establishment of an RRC connection with the access network device by restoring the first communication service. The first communication service is the communication service that was suspended before the first timer was started.

[0252] It should be noted that steps S1002 to S1007 above are optional.

[0253] Example 3: When searching for a cell, the terminal device can select a cell based on the first frequency band mentioned above. For example, the terminal device or access network device can set cells operating in the first frequency band as prohibited cells, so that the terminal device can select a cell for random access from cells other than the prohibited cells during cell search.

[0254] Optionally, if a suitable cell is selected for random access from among the cells outside the prohibited cells, the first timer is stopped. If no suitable cell is selected for random access from among the cells outside the prohibited cells, the system waits for the first timer to expire and then enters the RRC idle state after the first timer expires.

[0255] After the first timer expires, the terminal device can remain in the RRC idle state while still within the first area. Optionally, during this period, even if a communication service meets the conditions for triggering entry into the RRC connected state, the terminal device can suspend the communication service and remain in the RRC idle state.

[0256] After the first timer expires, when the terminal device leaves the first area, it can establish an RRC connection with the access network device. For example, the terminal device can trigger the establishment of an RRC connection with the access network device by resuming the first communication service. The first communication service is the communication service that was suspended before the first timer was started.

[0257] Currently, when a terminal device is in RRC connected state (RRC_CONNECTED), if a link problem is detected, such as RLF, RRC Connection Reconfiguration Failure, or Mobility from NR Failure, and the AS security mechanism is activated, the terminal device triggers an RRC re-establishment process. This application, however, uses entering the first region as the trigger condition for the RRC re-establishment process. This allows the terminal device to terminate communication by triggering the RRC re-establishment process upon entering the first region, thereby avoiding communication on the restricted frequency bands of the first region after entry, reducing the probability of not meeting the requirements of that region. Furthermore, this application allows the terminal device to autonomously avoid communication on restricted frequency bands, which helps reduce the decision-making risk for the network side, such as operators, and improves the decision-making flexibility of the terminal device.

[0258] This application uses entering the first region as the trigger condition for the RRC re-establishment process. Upon entering the first region, the terminal device terminates communication by triggering the RRC re-establishment process, thereby avoiding communication on the restricted frequency bands of the first region and reducing the probability of not meeting the region's requirements. Furthermore, this application allows the terminal device to autonomously avoid communication on restricted frequency bands, which helps reduce the decision-making risk for the network side, such as operators, and improves the decision-making flexibility of the terminal device.

[0259] Furthermore, this application can promptly restore the communication services of terminal devices through cell selection. Moreover, by considering the first frequency band and the cell priority related to the first frequency band during cell selection, it can, to some extent, avoid terminal devices communicating on restricted frequency bands in the first area, thereby reducing the probability of not meeting the requirements of the area.

[0260] This application also considers scenarios where the terminal device quickly leaves the first area, such as when the coverage area of ​​the first area is relatively small or the terminal device moves at a relatively fast speed. After the terminal device leaves the first area, a mechanism for re-selecting a cell is provided so that the terminal device can promptly select a suitable cell to resume communication without waiting for the first timer to expire. This helps to reduce the duration of communication interruptions for the terminal device and improves the user experience.

[0261] The above primarily describes the solutions provided in the embodiments of this application from the perspective of the interaction between terminal devices and access network devices. It is understood that, in order to achieve the above functions, the terminal devices and access network devices may include hardware structures and / or software modules corresponding to the execution of each function. Those skilled in the art should readily recognize that, in conjunction with the units and algorithm steps of the various examples described in the embodiments disclosed herein, the embodiments of this application can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed in hardware or by computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0262] This application embodiment can divide the access network device into functional units according to the above method example. For example, each function can be divided into a separate functional unit, or two or more functions can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0263] In the case of using integrated units, FIG11 shows a possible exemplary block diagram of the device involved in the embodiments of this application. As shown in FIG11, the device 1000 may include a processing unit 1002 and a communication unit 1003. The processing unit 1002 is used to control and manage the operation of the device 1000. The communication unit 1003 is used to support communication between the device 1000 and other devices. Optionally, the communication unit 1003 is also called a transceiver unit, and may include a receiving unit and / or a sending unit, respectively used to perform receiving and sending operations. The device 1000 may also include a storage unit 1001 for storing the program code and / or data of the device 1000.

[0264] The device 1000 can be the terminal device in the above embodiments. The processing unit 1002 can support the device 1000 in performing the actions of the terminal device in the method examples above. Alternatively, the processing unit 1002 mainly performs the internal actions of the terminal device in the method examples, and the communication unit 1003 can support communication between the device 1000 and other devices.

[0265] For example, in one embodiment, the communication unit 1003 is used to transmit and receive signals. The processing unit 1002 is used to: determine that it has entered a first area, the first area being a geographical area where communication on a specific frequency band is not permitted; and to start a first timer, the first timer being used to control the duration required for the cell selection process; and to perform cell selection via the communication unit 1003 during the timing of the first timer.

[0266] It should be understood that the division of units in the above device is merely a logical functional division. In actual implementation, they can be fully or partially integrated into a single physical entity, or they can be physically separated. Furthermore, all units in the device can be implemented entirely through software calls from processing elements; all units can be implemented entirely in hardware; or some units can be implemented through software calls from processing elements, and some units can be implemented in hardware. For example, each unit can be a separate processing element, or it can be integrated into a chip within the device. Alternatively, it can be stored as a program in memory, called and executed by a processing element of the device. Moreover, these units can be fully or partially integrated together, or implemented independently. The processing element mentioned here can also be called a processor, which can be an integrated circuit with signal processing capabilities. In the implementation process, the operations of the above methods or the various units mentioned above can be implemented through integrated logic circuits in the processor element or through software calls from processing elements.

[0267] In one example, a unit in any of the above devices can be one or more integrated circuits configured to implement the methods described above, such as: one or more application-specific integrated circuits (ASICs), or one or more digital signal processors (DSPs), or one or more field-programmable gate arrays (FPGAs), or a combination of at least two of these forms of integrated circuits. As another example, when a unit in the device can be implemented in the form of a processing element scheduler, the processing element can be a processor, such as a general-purpose central processing unit (CPU), or other processor capable of calling programs. Furthermore, these units can be integrated together to implement a system-on-a-chip (SOC).

[0268] The receiving unit described above is an interface circuit of the device, used to receive signals from other devices. For example, when the device is implemented as a chip, the receiving unit is an interface circuit for the chip to receive signals from other chips or devices. The transmitting unit described above is an interface circuit of the device, used to transmit signals to other devices. For example, when the device is implemented as a chip, the transmitting unit is an interface circuit for the chip to transmit signals to other chips or devices.

[0269] Figure 12 shows a schematic diagram of a communication device provided in an embodiment of this application. The communication device 1100 may be the circuit system of the terminal device described in the above embodiments, used to implement the method corresponding to the terminal device in the above method embodiments.

[0270] For specific functions, please refer to the description in the above method embodiments. For example, one type of circuit system is a chip system.

[0271] The communication device 1100 includes at least one processor 1101. The processor 1101 can be used for internal processing within the device to implement certain control processing functions. Optionally, the processor 1101 includes instructions. Optionally, the processor 1101 can store data. Optionally, different processors can be independent devices, located in different physical locations, or located on different integrated circuits. Optionally, different processors can be integrated into one or more processors, for example, integrated onto one or more integrated circuits.

[0272] Optionally, the communication device 1100 includes one or more memories 1103 for storing instructions. Optionally, the memories 1103 may also store data. The processor and the memories may be separate or integrated together.

[0273] Optionally, the communication device 1100 includes a communication line 1102 and at least one communication interface 1104. Since the memory 1103, communication line 1102, and communication interface 1104 are all optional, they are all represented by dashed lines in Figure 12.

[0274] Optionally, the communication device 1100 may further include a transceiver and / or an antenna. The transceiver can be used to send information to or receive information from other devices. The transceiver may be referred to as a transceiver unit, transceiver circuit, input / output interface, etc., and is used to realize the transmission and reception functions of the communication device 1100 via the antenna. Optionally, the transceiver includes a transmitter and a receiver. For example, the transmitter can be used to generate a radio frequency (RF) signal from a baseband signal, and the receiver can be used to convert the RF signal back into a baseband signal.

[0275] Processor 1101 may include a general-purpose central processing unit (CPU), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits for controlling the execution of programs according to the present application.

[0276] Communication line 1102 may include a path for transmitting information between the aforementioned components.

[0277] Communication interface 1104 uses any transceiver-like device for communicating with other devices or communication networks, such as Ethernet, radio access network (RAN), wireless local area network (WLAN), wired access network, etc.

[0278] The memory 1103 may be a read-only memory (ROM) or other type of static storage device capable of storing static information and instructions, random access memory (RAM) or other type of dynamic storage device capable of storing information and instructions, or electrically erasable programmable read-only memory (EEPROM), compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compressed optical discs, laser discs, optical discs, digital universal optical discs, Blu-ray discs, etc.), magnetic disk storage media or other magnetic storage devices, or any other medium capable of carrying or storing desired program code in the form of instructions or data structures and accessible by a computer, but not limited thereto. The memory 1103 may exist independently and be connected to the processor 1101 via communication line 1102. Alternatively, the memory 1103 may be integrated with the processor 1101.

[0279] The memory 1103 stores computer execution instructions for implementing the scheme of this application, and its execution is controlled by the processor 1101. The processor 1101 executes the computer execution instructions stored in the memory 1103, thereby implementing the steps performed by the terminal device described in the above embodiments.

[0280] Optionally, the computer execution instructions in the embodiments of this application may also be referred to as application code, and the embodiments of this application do not specifically limit this.

[0281] In a specific implementation, as one embodiment, processor 1101 may include one or more CPUs, such as CPU0 and CPU1 in FIG12.

[0282] In a specific implementation, as one embodiment, the communication device 1100 may include multiple processors, such as processors 1101 and 1105 in FIG. 12. Each of these processors may be a single-core (single-CPU) processor or a multi-core (multi-CPU) processor. Here, a processor may refer to one or more devices, circuits, and / or processing cores for processing data (e.g., computer program instructions).

[0283] When the device shown in Figure 12 is a chip, such as a chip in a terminal device, the chip includes a processor 1101 (and may also include a processor 1105), a communication line 1102, and a communication interface 1104. Optionally, it may include a memory 1103. Specifically, the communication interface 1104 may be an input interface, pins, or circuits, etc. The memory 1103 may be a register, cache, etc. The processor 1101 and processor 1105 may be a general-purpose CPU, microprocessor, ASIC, or one or more integrated circuits for controlling the execution of a program using the communication method of the above embodiments.

[0284] This application also provides a computer-readable storage medium for storing computer software instructions required to execute the processor, including a program required to execute the processor.

[0285] This application also provides a communication system, including a communication device for implementing the terminal device function in the embodiment of FIG8 and a communication device for implementing the access network device function in the embodiment of FIG8.

[0286] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0287] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to this application. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in one or more blocks of the flowchart illustrations and / or one or more blocks of the block diagrams.

[0288] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means that implement the functions specified in one or more flowcharts and / or one or more block diagrams.

[0289] These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, such that the instructions, which execute on the computer or other programmable apparatus, provide steps for implementing the functions specified in one or more flowcharts and / or one or more block diagrams.

[0290] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A communication method characterized by comprising: include: It is determined that the first area has been entered, which is a geographical area where communication on a specific frequency band is not allowed; Start the first timer, which controls the duration required for the cell selection process; Cell selection is performed during the first timer's countdown.

2. The method of claim 1, wherein, The cell selection process includes: Cell selection is based on at least one of the following: the specific frequency band, or the cell priority of at least one cell; Cells whose operating frequency band belongs to the specific frequency band have a lower cell priority than cells whose operating frequency band does not belong to the specific frequency band.

3. The method of claim 2, wherein, The method further includes: Receive cell priority information of the at least one cell.

4. The method according to any one of claims 1 to 3, characterized in that, The specific frequency band includes one or more frequency bands.

5. The method according to any one of claims 1 to 4, wherein The cell selection based on the specific frequency band includes: Perform a neighborhood search and select the first neighborhood; If the operating frequency band of the first cell does not belong to the specific frequency band, a random access is initiated to the first cell; If the operating frequency band of the first cell belongs to the specific frequency band, wait for the first timer to time out.

6. The method of claim 5, wherein, The method further includes: If a user leaves the first area during the period of waiting for the first timer to expire, cell selection will be performed again before the first timer expires.

7. The method of claim 6, wherein, The method further includes: If the user does not leave the first area during the timeout period of the first timer, the user enters the Radio Resource Control (RRC) idle state after the first timer expires.

8. The method according to any one of claims 5 to 7, wherein, The method further includes: After the first timer expires, it is determined that the user will leave the first area; Establish an RRC connection with the access network equipment.

9. A communication method characterized by comprising: include: Determine the cell priority of at least one cell; Send information about the cell priority of the at least one cell.

10. The method of claim 9, wherein, Cells whose operating frequency band belongs to a specific frequency band have a lower cell priority than cells whose operating frequency band does not belong to a specific frequency band.

11. The method of claim 9 or 10, wherein, Determining the cell priority of at least one cell includes: The cell priority of the at least one cell is determined based on the operating frequency band of the at least one cell.

12. The method according to any one of claims 9 to 11, characterized in that, Before determining the cell priority of at least one cell, the method further includes: Receive registration information, which is used for the terminal device to register with the UAV system service provider USS or the core network.

13. The method according to any one of claims 9 to 12, wherein, The cell priority information of at least one cell is carried in the subscription message; Alternatively, the cell priority information of the at least one cell may be carried in the Radio Resource Control (RRC) reconfiguration message.

14. A communications device, characterized by Includes modules or units for performing the method according to any one of claims 1 to 8.

15. A communications device, characterized by Includes modules or units for performing the method according to any one of claims 9 to 13.

16. A communications device, characterized by Includes a processor, the processor being configured to cause the communication device to perform the method of any one of claims 1 to 8.

17. A communications device, characterized by Includes a processor, the processor being configured to cause the communication device to perform the method of any one of claims 9 to 13.

18. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program or instructions that, when executed on a communication device, cause the communication device to perform the method as described in any one of claims 1 to 8, or the method as described in any one of claims 9 to 13.

19. A computer program product, characterised in that, The computer program product comprises computer programs or instructions which, when run on a communication device, cause the communication device to perform the method of any one of claims 1 to 8, or the method of any one of claims 9 to 13.

20. A communication system, characterized by The communication system comprises means for implementing the method of any one of claims 1 to 8 and means for implementing the method of any one of claims 9 to 13.

Images