Communication methods, apparatuses, and systems

Abstract

This application provides a communication method, apparatus, and system. In this method, when the radio frequency unit of a terminal device performs carrier switching, the switching interval is related to the downlink control channel capability of the terminal device, either on the first or second carrier. This can avoid the impact of the switching interval on the reception of the downlink control channel, thereby improving the performance of the communication system.

Description

Technical Field

[0001] This application relates to the field of communications, and more particularly to a communication method, apparatus, and system. Background Technology

[0002] The 3rd Generation Partnership Project (3GPP) introduced carrier aggregation (CA), which increases user transmission bandwidth by aggregating multiple consecutive or non-consecutive component carriers (CCs). This achieves multi-frequency resource integration, improves overall network resource utilization, and enhances user experience. To enable service transmission in carrier aggregation scenarios, terminals can switch radio frequency units between different CCs. Due to hardware processing latency, there is a switching gap / switching period during carrier switching, during which the radio frequency unit is in a non-operating state (considered an "interruption").

[0003] In the current technical solution, after carrier handover is triggered, the terminal will switch the operating carrier of the radio frequency unit from the source carrier (CC1) to the target carrier (CC2) in the next time slot, meaning that the handover interval is located on CC2. However, if the physical downlink control channel (PDCCH) of CC2 is located in the front-end symbol of the time slot, the "interruption" caused by the handover interval will prevent the terminal from successfully receiving the PDCCH and parsing the DCI, thus affecting the performance of the communication system. Summary of the Invention

[0004] This application provides a communication method, apparatus, and system to reduce the impact of handover interval on the performance of the communication system during carrier switching.

[0005] Firstly, this application provides a communication method applicable to a terminal device. This terminal device can be replaced by components configured within the terminal device (such as chips, chip systems, processors, etc.), or it can be replaced by logic modules or software that implement all or part of the functions of the terminal device, etc. This application does not limit the scope of the application in this regard.

[0006] In this method, the terminal device determines whether the handover interval is on the first carrier or the second carrier. The handover interval includes the time occupied by the working carrier of the radio frequency unit switching from the first carrier to the second carrier. Whether the handover interval is on the first carrier or the second carrier is related to the downlink control channel capability of the terminal device, and communication is carried out through the second carrier after the handover interval.

[0007] In this embodiment, the first carrier and the second carrier are different CCs in the CA scenario when the terminal device switches the radio frequency unit. In this embodiment, when the terminal device switches from the first carrier to the second carrier, the first carrier is the source carrier and the second carrier is the target carrier.

[0008] Downlink control channels can be, for example, PDCCH. The capability of a downlink control channel refers to the terminal equipment's capability related to receiving downlink control channels. For example, with different downlink control channel capabilities, the timing of downlink control channel detection supported by the terminal equipment varies. It can be understood that the higher the downlink control channel capability of the terminal equipment, the more flexible the timing of downlink control channel detection supported by the terminal equipment; in other words, the terminal equipment can detect downlink control channels at more time-domain locations. Therefore, the impact of the handover interval being located on the second carrier on the terminal equipment's reception of downlink control information is smaller. Conversely, the lower the downlink control channel capability of the terminal equipment, the more fixed the timing of downlink control channel detection supported by the terminal equipment; in other words, the terminal equipment detects downlink control channels at a limited number of time-domain locations. Therefore, the impact of the handover interval being located on the second carrier on the terminal equipment's reception of downlink control information is greater.

[0009] In other words, whether the handover interval is on the source carrier or the target carrier is related to the capability of the downlink control channel of the terminal device. This can avoid the problem that the downlink control channel cannot be successfully received when the handover interval is on the target carrier when the capability of the downlink control channel of the terminal device is low.

[0010] Based on this, when the radio frequency unit of the terminal device performs carrier switching, the switching interval is related to the capability of the downlink control channel of the terminal device, whether it is the first carrier or the second carrier. This can avoid the impact of the switching interval on the receiving downlink control channel, thereby improving the performance of the communication system.

[0011] Secondly, this application provides a communication method applicable to a network device. This network device can be replaced by components configured within it (such as chips, chip systems, processors, etc.), or it can be replaced by logic modules or software that implement all or part of the functions of the network device. This application does not limit the scope of this application.

[0012] In this method, the network device determines whether the handover interval is on the first carrier or the second carrier. The handover interval includes the time occupied by the working carrier of the radio frequency unit switching from the first carrier to the second carrier. Whether the handover interval is on the first carrier or the second carrier is related to the downlink control channel capability of the terminal device, and communication is carried out through the second carrier after the handover interval.

[0013] In one possible implementation of the first or second aspect described above, the handover interval being on the first or second carrier is related to the capability of the downlink control channel of the terminal device, including: under the first capability of the downlink control channel of the terminal device, the handover interval being on the first carrier; wherein, the first capability includes: the detection timing of the supported downlink control channel being located in the first n time domain resources of the time unit; or, the detection timing of the supported downlink control channel being located in any n time domain resources among the first N time domain resources of the time unit, where N is greater than n, and the time domain length of the handover interval is greater than or equal to the length of Nn time domain resources.

[0014] In other words, one scenario is that the terminal device supports the detection timing of the downlink control channel in the first n time domain resources of the time unit, and the handover interval needs to be placed on the first carrier to ensure that the detection timing of the downlink control channel on the second carrier is not affected by the interruption caused by carrier handover; another scenario is that the terminal device supports the detection timing of the downlink control channel in any n time domain resources in the first N time domain resources of the time unit, but the remaining Nn time domain resources are insufficient to complete the carrier handover. In order to avoid the impact of carrier handover on the detection timing of the downlink control channel of the terminal, the handover interval is placed on the first carrier.

[0015] In one possible implementation of the first or second aspect described above, the first capability further includes: supporting the scheduling of at least one secondary carrier by the primary carrier, wherein the second carrier is the primary carrier; or, supporting the scheduling of the primary carrier and / or at least one second secondary carrier by the first secondary carrier, wherein the second carrier is the first secondary carrier.

[0016] In other words, in both of the first capabilities described above, the second carrier needs to carry a downlink control channel. In this case, if the terminal device has limited flexibility in determining the timing of downlink control channel detection—for example, if the detection timing is located within the first n time domain resources of a time unit, or within any n time domain resources out of the first N time domain resources of a time unit, but the remaining Nn time domain resources are insufficient to complete carrier switching—then the switching interval will be placed on the first carrier. This reduces the impact on downlink control channel reception on the second carrier, thereby improving the performance of the communication system.

[0017] In one possible implementation of the first aspect above, determining whether the handover interval is on the first carrier or the second carrier under the second capability of the downlink control channel of the terminal device includes: the terminal device receiving a first radio resource control (RRC) signaling, the first RRC signaling indicating whether the handover interval is on the first carrier or the second carrier; wherein the second capability includes: the detection timing of the supported downlink control channel is located in any time domain resource of the time unit; or, the detection timing of the supported downlink control channel is located in any n time domain resources among the first N time domain resources of the time unit, where N is greater than n, and the time domain length of the handover interval is less than the length of Nn time domain resources.

[0018] In other words, one scenario is that the terminal device supports the detection timing of the downlink control channel in any time domain resource of the time unit. Even if the handover interval is in the second carrier, it can avoid affecting the detection of the downlink control channel. Therefore, the handover interval in the first or second carrier can be flexibly configured by the network device through RRC signaling. Another scenario is that the terminal device supports the detection timing of the downlink control channel in any n time domain resources in the first N time domain resources of the time unit, and the carrier handover can be completed in the remaining Nn time domain resources. This can avoid the impact of the interruption caused by the carrier handover on the detection timing of the receiving downlink control channel. Therefore, the handover interval in the first or second carrier can be flexibly configured by the network device through RRC signaling.

[0019] In one possible implementation of the second aspect above, determining whether the handover interval is on the first carrier or the second carrier under the second capability of the downlink control channel of the terminal device includes: the network device sending a first RRC signaling, the first RRC signaling indicating that the handover interval is on the first carrier or the second carrier; wherein the second capability includes: the detection timing of the supported downlink control channel is located in any time domain resource of the time unit; or, the detection timing of the supported downlink control channel is located in any n time domain resources among the first N time domain resources of the time unit, where N is greater than n, and the time domain length of the handover interval is less than the length of Nn time domain resources.

[0020] In one possible implementation of the first aspect above, determining whether the handover interval is on the first carrier or the second carrier under the third capability of the downlink control channel of the terminal device includes: the terminal device receiving a second RRC signaling, the second RRC signaling indicating that the handover interval is on the first carrier or the second carrier; wherein the third capability includes:

[0021] The system supports scheduling of a primary carrier to at least one secondary carrier, wherein the second carrier is the secondary carrier; or, the system supports scheduling of a first secondary carrier to a primary carrier and / or at least one second secondary carrier, wherein the second carrier is either the primary carrier or the second secondary carrier.

[0022] as well as,

[0023] The detection timing of the supported downlink control channel is located in the first n time domain resources of the time unit; or, the detection timing of the supported downlink control channel is located in any n time domain resources in the first N time domain resources of the time unit, where N is greater than n, and the time domain length of the handover interval is greater than or equal to the length of Nn time domain resources.

[0024] In other words, although the downlink control channel detection timing supported by the terminal device has low flexibility, such as supporting downlink control channel detection timing in the first n time domain resources of the time unit, or supporting downlink control channel detection timing in any n time domain resources in the first N time domain resources of the time unit, the remaining Nn time domain resources are insufficient to complete the carrier handover. However, in cross-carrier scheduling or multi-carrier scheduling scenarios, the second carrier does not need to carry the downlink control channel. That is, even if the handover interval is on the second carrier, it can avoid affecting the detection of the downlink control channel. Therefore, the handover interval located on the first carrier or the second carrier can be flexibly configured by the network device through RRC signaling.

[0025] In one possible implementation of the second aspect above, determining whether the handover interval is on the first carrier or the second carrier under the third capability of the downlink control channel of the terminal device includes: the network device sending a second RRC signaling, the second RRC signaling indicating whether the handover interval is on the first carrier or the second carrier; wherein the third capability includes:

[0026] The system supports scheduling of a primary carrier to at least one secondary carrier, wherein the second carrier is the secondary carrier; or, the system supports scheduling of a first secondary carrier to a primary carrier and / or at least one second secondary carrier, wherein the second carrier is either the primary carrier or the second secondary carrier.

[0027] as well as,

[0028] The detection timing of the supported downlink control channel is located in the first n time domain resources of the time unit; or, the detection timing of the supported downlink control channel is located in any n time domain resources in the first N time domain resources of the time unit, where N is greater than n, and the time domain length of the handover interval is greater than or equal to the length of Nn time domain resources.

[0029] In one possible implementation of the first or second aspect above, determining whether the handover interval is on the first carrier or the second carrier includes: determining whether the handover interval is on the first carrier or the second carrier based on the capability of the downlink control channel of the terminal device.

[0030] In other words, the terminal device determines whether the handover interval is on the first or second carrier based on preset rules and its own downlink control channel capabilities. Correspondingly, the network device can determine whether the handover interval is on the first or second carrier based on the same rules and the downlink control channel capabilities of the terminal device, thereby realizing carrier handover in CA scenarios and reducing the impact of the handover interval on the transmission downlink control channel.

[0031] In one possible implementation of the first aspect above, determining whether the handover interval is on the first carrier or the second carrier includes: the terminal device receiving third RRC signaling, the third RRC signaling being used to configure the handover interval; and determining whether the handover interval is on the first carrier or the second carrier based on the third RRC signaling.

[0032] Based on this, terminal devices can determine the switching interval based on the network device configuration, thereby reducing the information processing complexity of terminal devices.

[0033] In one possible implementation of the second aspect above, the network device further includes sending a third RRC signaling message, which is used to configure the handover interval.

[0034] In one possible implementation of the first or second aspect above, the capabilities of the downlink control channel that the terminal device must select include:

[0035] The supported downlink control channel detection timing is located in any n time-domain resources within the first N time-domain resources of the time unit, where N is greater than n; or,

[0036] The detection timing of the supported downlink control channel is located at any time domain resource within the time unit.

[0037] In other words, when the terminal device is required to support the enhanced downlink control channel, the above-mentioned process of determining whether the handover interval is on the first or second carrier and performing carrier handover based on the handover interval is performed. This avoids the problem that when there are multiple terminal devices in the cell that require carrier handover, the network device has to determine the position of the handover interval for each terminal device during carrier handover, which leads to greater scheduling difficulty and overhead for the network device.

[0038] In one possible implementation of the first or second aspect described above, the capability of the downlink control channel, which is mandatory for the terminal device, also includes:

[0039] Supports scheduling of the primary carrier to at least one secondary carrier; or,

[0040] It supports scheduling of the primary carrier and / or at least one second secondary carrier by the first secondary carrier.

[0041] In other words, in addition to supporting enhanced downlink control channel detection capabilities, terminal devices also need to support enhanced carrier scheduling capabilities, such as cross-carrier scheduling or multi-carrier scheduling. Based on this, the scheduling difficulty and overhead of network devices can be further reduced.

[0042] The second aspect corresponds to the technical solution of the first aspect of this application. The beneficial effects achieved by each aspect and the corresponding feasible implementation are similar, and will not be repeated here.

[0043] Thirdly, this application provides a communication device, including modules or units for implementing the methods of the first aspect or the second aspect and any possible implementation of the first aspect or the second aspect. Specifically, the modules, units, or means can be implemented in software, in hardware, or in a combination of software and hardware.

[0044] Fourthly, this application provides a communication device including one or more processors, the one or more processors being configured to execute a computer program (also referred to as code or instructions) in a memory, such that the communication device implements the communication method in the first aspect or the second aspect and any possible implementation of the first aspect or the second aspect.

[0045] Optionally, the device further includes a memory for storing computer programs and data. The memory is coupled to the processor, which, when executing the computer program stored in the memory, can implement the methods described in the first or second aspect above.

[0046] Optionally, the device further includes a communication interface for communicating with other devices. For example, the communication interface may be a transceiver, circuit, bus, module, or other type of communication interface.

[0047] Fifthly, this application provides a chip system including at least one processor for supporting the implementation of the functions involved in the first or second aspect and any possible implementation of the first or second aspect, such as processing the information involved in the above methods.

[0048] In one possible design, the chip system also includes a memory for storing computer programs and data, which may be located inside or outside the processor.

[0049] The chip system can consist of chips or include chips and other discrete components.

[0050] In one possible design, the chip system also includes a power supply circuit for supplying power to the chip system.

[0051] In a sixth aspect, this application provides a computer-readable storage medium including a computer program that, when run on a computer, causes the computer to implement the methods of the first or second aspect and any possible implementation of the first or second aspect.

[0052] In a seventh aspect, this application provides a computer program product comprising: a computer program that, when run, causes a computer to perform the methods of the first or second aspect and any possible implementation thereof.

[0053] Eighthly, embodiments of this application provide a system including the aforementioned terminal and network device.

[0054] The third to eighth aspects of this application correspond to the technical solutions of the first aspect of this application. The beneficial effects achieved by each aspect and the corresponding feasible implementation are similar, and will not be repeated here. Attached Figure Description

[0055] Figure 1 This is a schematic diagram of the architecture of the communication system provided in the embodiments of this application;

[0056] Figure 2 This is a schematic diagram of a carrier aggregation scenario provided in an embodiment of this application;

[0057] Figure 3 This is a schematic diagram of low-frequency carrier switching provided in an embodiment of this application;

[0058] Figure 4 This is a schematic diagram of a carrier switching method provided in an embodiment of this application;

[0059] Figure 5 This is a schematic diagram of a carrier switching method provided in an embodiment of this application;

[0060] Figure 6 This is a schematic flowchart illustrating a communication method provided in an embodiment of this application;

[0061] Figure 7 This is a schematic diagram of carrier switching based on downlink control channel capability provided in an embodiment of this application;

[0062] Figure 8 This is a schematic flowchart illustrating a communication method provided in an embodiment of this application;

[0063] Figure 9 This is a schematic flowchart illustrating a communication method provided in an embodiment of this application;

[0064] Figure 10 A schematic block diagram of a communication device provided for embodiments of this application;

[0065] Figure 11 A schematic block diagram of another communication device provided for embodiments of this application;

[0066] Figure 12 A schematic block diagram of another communication device provided for embodiments of this application. Detailed Implementation

[0067] The technical solution provided in this application will now be described with reference to the accompanying drawings.

[0068] To facilitate understanding of the embodiments of this application, the following points will be explained first:

[0069] First, in this application, "at least one" means one or more, and "more than one" means two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can mean: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. The character " / " generally indicates an "or" relationship between the preceding and following related objects, but it does not exclude the possibility of indicating an "and" relationship; the specific meaning can be understood in context. "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 mean: a, b, c; a and b; a and c; b and c; or a and b and c. Here, a, b, and c can be single or multiple.

[0070] Second, in this application, the use of prefixes such as "first" and "second" is merely for the purpose of distinguishing and describing different things belonging to the same category of names, and does not constrain the order, size, or quantity of things. For example, "first carrier" and "second carrier" are simply different carriers.

[0071] Third, in the embodiments of this application, "when," "if," and "if" all refer to the device making corresponding processing under certain objective circumstances, and are not limited to a time, nor do they require the device to make a judgment action when it is implemented, nor do they mean that there are other limitations.

[0072] The technical solutions provided in this application can be applied to various communication systems, such as: Long Term Evolution (LTE) systems, LTE Frequency Division Duplex (FDD) systems, LTE Time Division Duplex (TDD) systems, sidelink (SL) communication systems, Universal Mobile Telecommunication System (UMTS), Worldwide Interoperability for Microwave Access (WiMAX) communication systems, 5th Generation (5G) mobile communication systems, or new radio access technology (NR). Among these, 5G mobile communication systems can include non-standalone (NSA) and / or standalone (SA) networking. The technical solutions provided in this application can also be applied to future communication systems. This application does not limit the scope of these applications.

[0073] Figure 1 This is a schematic diagram of the architecture of a communication system applicable to the communication method provided in this application. Figure 1 A schematic diagram of a possible, non-limiting system architecture is shown. (e.g.) Figure 1 As shown, the communication system 100 includes a radio access network (RAN) 10 and a core network (CN) 20. Optionally, the communication system 100 also includes an Internet 30. The RAN 10 includes at least one RAN node (e.g., Figure 1 110a and 110b (collectively referred to as 110) and at least one terminal (such as Figure 1 RAN 10, denoted as RAN 10 (120a-120j), may also include other RAN nodes, such as wireless relay devices and / or wireless backhaul devices. Figure 1 (Not shown in the image). Terminal 120 is connected to RAN node 110 wirelessly. RAN node 110 is connected to core network 20 wirelessly or via wired connection. The core network equipment in core network 20 and RAN node 110 in RAN 10 can be different physical devices, or they can be the same physical device integrating core network logical functions and radio access network logical functions.

[0074] RAN 10 can be a cellular system related to the 3rd Generation Partnership Project (3GPP), such as 4G, 5G mobile communication systems, or future-oriented evolution systems. RAN 10 can also be an open access network (O-RAN or ORAN), a cloud radio access network (CRAN), or a wireless fidelity (Wi-Fi) system. RAN 10 can also be a communication system that integrates two or more of the above systems.

[0075] RAN node 110, sometimes also referred to as access network equipment, RAN entity, or access node, is part of the communication system and is used to help terminals achieve wireless access. Multiple RAN nodes 110 in communication system 100 can be of the same type or different types. In some scenarios, the roles of RAN node 110 and terminal 120 are relative, for example... Figure 1 Network element 120i can be a helicopter or a drone, and it can be configured as a mobile base station. For terminals 120j that access RAN 10 through network element 120i, network element 120i is a base station; however, for base station 110a, network element 120i is a terminal. RAN node 110 and terminal 120 are sometimes referred to as communication devices, for example... Figure 1 Network elements 110a and 110b can be understood as communication devices with base station functions, while network elements 120a-120j can be understood as communication devices with terminal functions.

[0076] In one possible scenario, a RAN node can be a base station, an evolved NodeB (eNodeB), an access point (AP), a transmission reception point (TRP), a next-generation NodeB (gNB), a next-generation base station in a future communication system, a base station in a future mobile communication system, or an access node in a WiFi system, etc. A RAN node can also be a macro base station (such as...) Figure 1 110a), micro base stations or indoor stations (such as Figure 1In CRAN scenarios, RAN nodes can be 110b, relay nodes, donor nodes, or wireless controllers. Optionally, RAN nodes can also be servers, wearable devices, vehicles, or in-vehicle equipment. For example, in vehicle-to-everything (V2X) technology, the access network equipment can be a roadside unit (RSU).

[0077] In another possible scenario, multiple RAN nodes collaborate to assist the terminal in achieving wireless access, with different RAN nodes each implementing a portion of the base station's functions. For example, RAN nodes can be central units (CUs), distributed units (DUs), CU-control plane (CPs), CU-user plane (UPs), or radio units (RUs), etc. 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).

[0078] 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. For example, in an ORAN system, CU can also be called O-CU (open 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 ease of description, this application uses CU, CU-CP, CU-UP, DU, and RU as examples. 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.

[0079] A terminal can also be called a terminal device, user equipment (UE), mobile station, mobile terminal, etc. Terminals 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. Terminals can be mobile phones, tablets, computers with wireless transceiver capabilities, wearable devices, vehicles, drones, helicopters, airplanes, ships, robots, robotic arms, smart home devices, etc.

[0080] In the embodiments of this application, the terminal and network device can be hardware devices, or software functions running on dedicated hardware, or software functions running on general-purpose hardware, such as virtualization functions instantiated on a platform (e.g., cloud platform), or entities that include dedicated or general-purpose hardware devices and software functions. This application does not limit the specific form of the terminal and network device.

[0081] To better understand the methods provided in the embodiments of this application, the terms involved in this application will be briefly explained below.

[0082] 1. CA: By aggregating multiple consecutive or non-consecutive CCs, bandwidth utilization is improved, thereby increasing the communication rate to meet 3GPP requirements.

[0083] CA includes, but is not limited to, low-frequency CA, high-frequency CA, and high-low frequency CA. In this application, the number of CCs included in the CA scenario is not limited; for example, it supports, but is not limited to, 2CC, 3CC, 4CC, or 5CC CA.

[0084] See Figure 2 As shown, in a 3-carrier aggregation scenario, a terminal can use 3 carriers simultaneously. One of these carriers is called the primary carrier (PCC). The PCC carries signaling and manages the other secondary carriers (SCCs). Cell 1, corresponding to the PCC, is the primary cell (PCell); the cells corresponding to the SCCs (such as cells 2 and 3) are called secondary cells (SCells).

[0085] In this context, the PCell is the cell where the CAUE establishes an initial connection, performs radio resource control (RRC) connection reconstruction, or is the primary cell designated during handover. The PCell is responsible for RRC communication with the UE. The CA UE operates within this cell similarly to a single-carrier cell. PCC refers to the CC corresponding to the PCell. The downlink carrier of the PCell is called the downlink (DL) PCC, and the uplink carrier is called the uplink (UL) PCC.

[0086] Among them, CA UE refers to UE that supports CA function.

[0087] A SCell is a cell configured for a CA UE during RRC reconfiguration to provide additional radio resources. There is no RRC communication between the SCell and the UE. A SCell can have only downlink or both uplink and downlink. SCC refers to the CC corresponding to the SCell. The downlink carrier of the SCell is called DL SCC, and the uplink carrier of the SCell is called UL SCC.

[0088] A serving cell (such as a PCell or SCell) may contain only one downlink carrier, one downlink carrier and one uplink carrier, or one downlink carrier and two uplink carriers. Therefore, a serving cell can correspond one-to-one with one downlink carrier, so the concepts of carrier (unless otherwise specified, all terms refer to downlink carriers) and cell can be used interchangeably in this invention.

[0089] 2. Carrier switching: This involves dynamically adjusting the operating carrier of the terminal's radio frequency unit in a multi-carrier environment within a CA scenario, thereby achieving network load balancing and optimizing network performance.

[0090] Carrier handover includes single-CC handover and multi-CC handover. In single-CC handover, the terminal can switch its radio frequency unit from one CC to another; in multi-CC handover, the terminal can switch its radio frequency unit from multiple aggregated carriers (such as CC1, CC2) to multiple target carriers (such as CC3 and CC4).

[0091] Switching a terminal's radio frequency unit from one control area (CC) to another requires a certain amount of hardware processing time. During this time, the terminal's radio frequency unit is in a non-operating state, considered an "interruption," which can be called the switching gap / switching period. Currently, the time domain length of the switching gap can include two values: 35µs and 140µs. The terminal reports its capabilities to the network device; that is, for terminals with longer hardware processing times, a capability matching the 140µs value is reported, and vice versa. This application does not limit the time domain length of the switching gap; for example, other possible values ​​of the switching gap supported in future protocols are all within the scope of protection of this application.

[0092] 3. Downlink control channel: such as PDCCH, used to carry downlink control information (DCI).

[0093] DCI can be used to schedule data transmission resources, such as scheduling the physical downlink shared channel (PDSCH) or the physical uplink shared channel (PUSCH). For example, DCI may include resource block (RB) indicators, coding and modulation schemes, hybrid automatic repeat request (HARQ), and other related components.

[0094] In this embodiment, the downlink control channel can be located within a time unit. The position of the downlink control channel within the time unit can be referred to as the detection timing of the downlink control channel. The terminal can detect the PDCCH at the detection timing of the downlink control channel, thereby communicating based on the data transmission resources scheduled by the DCI. The detection timing of the downlink control channel can be configured by dedicated RRC signaling, such as the detection timing of type-1 common search space (CSS), type-2 CSS, and user-specific search space (UE-SS, or USS) configured by the RRC signaling.

[0095] 4. Time Unit: This can be a slot, subframe, or orthogonal frequency division multiplexing (OFDM) symbol (hereinafter referred to as symbol), or other time units to be defined in the future. It should be noted that a time unit is a unit of measurement in the time domain and is not necessarily the smallest time unit.

[0096] In NR, a time slot is a scheduling unit. The following description uses a time slot as an example of a time unit to illustrate the method provided in this application. It is understood that the description of time slots in the following embodiments can be replaced with other time units, such as subframes, symbols, etc. This application does not limit this.

[0097] In this embodiment of the application, a time unit may include multiple time-domain resources. The time-domain resources may be time-domain partitions with a smaller granularity than the time unit. For example, the time-domain resources may be symbols in a time slot. For example, each time slot may include 14 symbols.

[0098] The following is based on Figure 3 The following example illustrates low-frequency carrier switching. Low-frequency bands (e.g., sub-1GHz) are core frequency bands for operators' wide area network deployments due to their excellent electromagnetic wave propagation characteristics. However, the ever-increasing data traffic has caused congestion in low-frequency bands, impairing user experience. One solution is to use carrier aggregation to allocate multiple low-frequency carriers to users. For example, ... Figure 3 The n12 and n29 frequency bands, belonging to several operators, are allocated to terminals. The n12 band is a frequency division duplex (FDD) band, with 729MHz-746MHz used for downlink transmission and 669MHz-716MHz for uplink transmission, with a subcarrier spacing of 15kHz. The n29 band is a supplementary downlink (SDL) band: 717MHz-728MHz, used as a supplementary downlink band with no uplink resources, and a subcarrier spacing of 15kHz. Because the n12 band is congested, the n29 band, as a supplementary downlink band, is used in conjunction with n12 to solve the problem of excessive congestion in the n12 band. The carrier unit corresponding to the PCell of the terminal is located in the n12 frequency band, of which the DL PCC is located in the 729MHz-746MHz frequency band and the UL PCC is located in the 669MHz-716MHz frequency band; the carrier unit corresponding to the SCell of the terminal is located in the n29 frequency band, and the DL SCC is located in the 717MHz-728MHz frequency band.

[0099] For some low-capacity terminals, which often only have one RF receiver unit and cannot simultaneously receive data on both the PCell and SCell, carrier switching between the n29 and n12 frequency bands is necessary to achieve data reception. However, due to the limited 1MHz isolation bandwidth between the n12 uplink and n29 downlink bands, and constrained by the terminal's duplexer hardware, when the terminal switches to downlink transmission on the n29 band, it cannot perform uplink transmission on the n12 band. Therefore, the terminal switches the operating carrier of its RF receiver unit between the n12 and n29 bands to address low-frequency congestion. See also... Figure 4 As shown, a feasible multi-band utilization method is as follows: After the terminal's RF receiving unit operates in the n12 band for a period of time, the operating carrier of the RF receiving unit is switched from the n12 band to the n29 band to receive downlink data. After a period of time, the operating carrier of the RF receiving unit is switched back from the n29 band to the n12 band. Each cell represents a time slot, D represents a downlink time slot, and U represents an uplink time slot (the n12 band is an FDD band, therefore it has both uplink and downlink time slots; the n29 band is an SDL band, only having a downlink time slot). Gray cells indicate that the terminal is transmitting or receiving signals in that time slot, and white cells indicate that the terminal is not operating in that time slot.

[0100] It should be noted that the above descriptions of the n12 and n29 frequency bands are for illustrative purposes only. The background and related technologies of this solution can be applied to other frequency band combinations, including but not limited to combinations of another FDD frequency band and an SDL frequency band, combinations of FDD frequency bands, combinations of FDD frequency bands and TDD frequency bands, etc. Furthermore, this application only uses low-frequency carrier handover and low-capability terminals as examples to illustrate carrier handover, but does not limit the applicable scenarios of this application. For example, the solution in the embodiments of this application can be applied to carrier handover in any frequency band for terminals of any capability.

[0101] It should also be understood that the embodiments of this application only take the switching between two CCs as an example, but are not limited thereto. For example, in a multi-carrier aggregation scenario, the terminal can switch the operating carrier of the radio frequency unit from CC1 to CC2, and then from CC2 to CC3, etc. When the terminal performs multiple carrier switching on the radio frequency unit, the scheme provided in this application applies to each carrier switching. For ease of description, the source carrier during carrier switching is referred to as the first carrier, and the target carrier is referred to as the second carrier.

[0102] This application does not limit the radio frequency unit that performs carrier switching to a radio frequency receiving unit; for example, it can also be used for carrier switching of a radio frequency transmitting unit. Hereinafter, it will be referred to as a radio frequency unit.

[0103] See Figure 5As shown, the terminal's radio frequency unit operates on the first carrier. After the carrier switching is triggered, the terminal will switch the working carrier of the radio frequency unit from the first carrier to the second carrier in the next time slot. That is, the switching interval is located on the second carrier. If the PDCCH on the second carrier is located in the first few symbols of the time slot, the "interruption" caused by the switching interval will prevent the terminal from successfully receiving the PDCCH and parsing the DCI, thus preventing data transmission based on the DCI scheduling and affecting the performance of the communication system.

[0104] In view of this, the handover interval in the embodiments of this application is located on the first carrier or the second carrier and is related to the capability of the terminal's downlink control channel. In other words, the capability of the terminal's downlink control channel determines whether the handover interval is placed on the first carrier or the second carrier, so as to avoid the impact of always placing the handover interval on the second carrier on the detection of the downlink control channel, thereby improving the performance of the communication system.

[0105] The methods provided in the embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0106] This application describes the method provided by this application from the perspective of interaction between a terminal device and a network device, but this should not be construed as limiting this application in any way. Furthermore, the terminal device can be replaced by components within the terminal device, such as chips, chip systems, processors, etc., or by logic modules or software capable of implementing some or all of its functions; the network device can be replaced by components within the network device, such as chips, chip systems, processors, etc., or by logic modules or software capable of implementing some or all of its functions. This application does not impose any limitations in this regard.

[0107] Figure 6 This is a schematic flowchart of the communication method provided in the embodiments of this application. Figure 6 The method 200 shown may include some or all of the following steps:

[0108] S210, the network device determines whether the handover interval is on the first carrier or the second carrier. The handover interval includes the time occupied by the working carrier of the radio frequency unit when it switches from the first carrier to the second carrier. Whether the handover interval is on the first carrier or the second carrier is related to the downlink control channel capability of the terminal device.

[0109] In this embodiment, the first carrier and the second carrier are different carriers (CCs) for the terminal device to switch the operation of the radio frequency unit in the CA scenario. When the terminal device switches from the first carrier to the second carrier, the first carrier is the source carrier, which is the current operating carrier of the radio frequency unit of the terminal device, and the second carrier is the target carrier.

[0110] In this embodiment, the network device can instruct the terminal device to perform carrier switching, such as by instructing the terminal device to perform carrier switching via RRC signaling. Alternatively, carrier switching can be triggered by preset or pre-configured rules. The preset rules can be, for example, rules for triggering switching as agreed upon by a protocol, such as a protocol-defined mode for the terminal device to periodically trigger carrier switching. The period of carrier switching can be pre-configured or preset, as agreed upon by the protocol; or, the protocol can define a switching to be triggered when the channel quality is below a threshold.

[0111] In this embodiment, carrier switching can occur at the boundary (or edge) of a time unit. Carrier switching at the boundary of a time unit can mean that different carriers are used for communication in two adjacent time units. For example, in the first time unit, the network device and the terminal device communicate using the first carrier, and in the second time unit (the time unit following the first time unit), the network device and the terminal device switch to communicating using the second carrier. Whether carrier switching occurs at the boundary of a time unit can be determined based on the indication of RRC signaling or the rules for triggering switching agreed upon in the protocol.

[0112] In other words, when carrier switching occurs at the boundary of a time unit, the network device and the terminal device communicate using the first carrier in the first time unit, and switch to communicating using the second carrier in the next second time unit. Here, the first time unit is the time unit configured to communicate using the first carrier, and the second time unit is the time unit configured to communicate using the second carrier. The meaning of "carrier switching occurs at the boundary of a time unit" in the following text is similar and will not be elaborated further for the sake of brevity.

[0113] A handover interval on the first carrier means that during the handover interval, the terminal device is unable to receive or transmit signals on the first carrier due to an interruption caused by hardware switching; a handover interval on the second carrier means that during the handover interval, the terminal device is unable to receive or transmit signals on the second carrier due to an interruption caused by hardware switching.

[0114] Based on this, a handover interval on the first carrier can mean that the terminal device switches the operating carrier of the radio frequency unit from the first carrier to the second carrier in the first time unit, or it can be described as the handover interval being within the first time unit. In this case, the handover interval can be located in the last m time domain resources of the first time unit, and the number m of time domain resources occupied by the handover interval is related to the time domain length of the handover interval supported by the terminal device. The following descriptions of the handover interval being on the first carrier or other source carriers have similar meanings and will not be repeated for the sake of brevity.

[0115] Correspondingly, a handover interval on the second carrier can mean that the terminal device switches the operating carrier of its radio frequency unit from the first carrier to the second carrier in the second time unit, or it can be described as the handover interval being in the time unit corresponding to the second carrier. In this case, the handover interval can be in the first m time domain resources of the second time unit, and the number m of time domain resources occupied by the handover interval is related to the time domain length of the handover interval supported by the terminal device. The following descriptions of handover intervals on the second carrier or other target carriers have similar meanings and will not be repeated for the sake of brevity.

[0116] The downlink control channel (HDC) can be referred to in the above description, and will not be repeated here for brevity. For example, it could be a PDCCH carrying DCI. The HDC capability of a terminal device can include its ability to detect the HDC, such as the locations where the terminal device supports detecting the HDC, or the timing of HDC detection supported by the terminal device. Generally speaking, the higher the HDC detection capability of the terminal device, the more flexible the timing of HDC detection supported by the terminal device, or in other words, the more time-domain locations the terminal device can detect the HDC. Therefore, when the handover interval is located on the second carrier, the impact on the terminal device's reception of HDC information is smaller. Conversely, the lower the HDC capability of the terminal device, the more fixed the timing of HDC detection supported by the terminal device, or in other words, the terminal device detects the HDC in a limited number of time-domain locations. Therefore, when the handover interval is located on the second carrier, the impact on the terminal device's reception of HDC information is greater.

[0117] In NR systems, when a terminal device detects the downlink control channel, its basic capabilities should support: the downlink control channel detection timing should be within the first three symbols of a timeslot. This capability is protocol-defined and does not require the terminal device to report it. If the terminal device does not report its capabilities regarding the downlink control channel detection timing, the network device can configure the detection timing of the Type-1 CSS, Type-3 CSS, or UE-SS via dedicated RRC signaling to be within the first three symbols of a timeslot.

[0118] In NR systems, when terminal devices have a high level of support for downlink channel detection timing and location, these enhanced terminal devices can report their capabilities. This application does not limit the signaling used by the terminal devices when reporting capabilities. For example, terminal devices can report capabilities through RRC signaling, such as using information elements (IE) in RRC to indicate the relevant capabilities for detecting downlink control channels.

[0119] For example, if RRC IE: "pdcch-MonitoringAnyOccasions" or "pdcch-MonitoringAnyOccasionsWithSpanGap" or "pdcch-MonitoringAnyOccasionsWithSpanGapCrossCarrierSch-r16" exists, then for the Type-1 CSS, Type-3 CSS and UE-SS configured in the dedicated RRC, the detection opportunities supported by the terminal equipment can be located within any symbol of a time slot.

[0120] For example, if RRC IE: "pdcch-MonitoringSingleSpanFirst4Sym-r16" (PDCCH single-span detection for the first 4 symbols in R16 version) exists, then for Type-1 CSS, Type-3 CSS, and UE-SS configured in dedicated RRC, the terminal device can support detection timing on any 3 consecutive symbols within the first 4 symbols of a time slot. For example, the first 3 symbols of a time slot; or the 2nd, 3rd, and 4th symbols of a time slot.

[0121] This application uses the aforementioned NR system as an example to illustrate the terminal device's support for downlink control channel detection timing and location, but does not limit it. The terminal device may also include support for other downlink control channel detection timing and location capabilities, and may also report capabilities through other RRC cells; this application does not limit this. For ease of description, the terminal device's support for downlink control channel detection timing and location will be summarized below as the terminal device's downlink control channel detection capability.

[0122] In one possible example, the terminal device's ability to detect the downlink control channel can be summarized into the following three types:

[0123] The first type: the detection timing of the downlink control channel supported by the terminal device is located in the first n time domain resources of the time unit; or,

[0124] The second type: the detection timing of the downlink control channel supported by the terminal device is located in any time domain resource of the time unit; or,

[0125] The third type: The detection timing of the downlink control channel supported by the terminal device is located in any n time domain resources in the first N time domain resources of the time unit, where N is greater than n.

[0126] In the first type of downlink control channel detection capability described above, the terminal device can detect the downlink control channel and receive downlink control information on the first n time domain resources of the time unit on the second carrier, thereby performing communication based on the scheduling of the downlink control information. If the handover interval is on the second carrier, the terminal device cannot successfully receive the downlink control information. In this case, the network device determines that the handover interval is on the first carrier.

[0127] See Figure 7 In (a) of the above, when the downlink control channel detection opportunity supported by the terminal device is located in the first n time domain resources of a time unit, the carrier handover of the terminal device occurs at the boundary of the time unit. For example, if the terminal device performs a carrier handover from CC1 to CC2 at the boundary of the first time unit, since there is a downlink control channel detection opportunity in the first n time domain resources of the second time unit on CC2, if the handover interval is CC2, it will affect the terminal device's reception of downlink control information within that detection opportunity. Therefore, the network device determines that the handover interval is CC1. If the handover interval is in the last m time domain resources of the first time unit on CC1, it can avoid the terminal device from being unable to successfully receive downlink control information, thus affecting data transmission. Similarly, if the terminal device performs a carrier handover from CC2 to CC1 at the boundary of the third time unit, since there is a downlink control channel detection opportunity in the first n time domain resources of the fourth time unit on CC1, the network device determines that the handover interval is CC2. If the handover interval is in the last m time domain resources of the third time unit on CC2, it can avoid the terminal device from being unable to successfully receive downlink control information, thus affecting data transmission.

[0128] In the second type of downlink control channel detection capability described above, the terminal device can detect the downlink control channel and receive downlink control information on any time-domain resource within the time unit of the second carrier, thereby enabling communication based on the scheduling of the downlink control information. In this case, even if the handover interval is on the second carrier, the overlap between the handover interval and the downlink control channel detection timing can be avoided, thus preventing carrier handover from affecting the terminal device's reception of downlink control information. That is, the handover interval can be on either the first or the second carrier.

[0129] See Figure 7In (b), when the detection timing of the downlink control channel supported by the terminal device is located in any time domain resource of the time unit, when the terminal device performs a carrier handover from CC1 to CC2 at the boundary of the first time unit, since the time domain position of the downlink control channel in the second time unit on CC2 does not overlap with the handover interval, the network device can determine that the handover interval is in CC2, such as the first m time domain resources of CC2, or it can also determine that the handover interval is in CC1 (shown as a dashed line in the figure), such as the last m time domain resources of CC1. It can be understood that the network device can transmit downlink control information on the first few time domain resources of the time unit of CC2, so the handover interval should be in CC1. Similarly, when a terminal device performs a carrier handover from CC2 to CC1 at the boundary of the third time unit, since the time domain position of the downlink control channel in the fourth time unit of CC1 does not overlap with the handover interval, the network device can determine that the handover interval is in CC1, such as the first m time domain resources of CC1, or it can determine that the handover interval is in CC2 (shown as a dashed line in the figure), such as the last m time domain resources of CC2. It should also be understood that if the network device transmits downlink control information on the first few time domain resources of the time unit of CC1, then the handover interval should be in CC2.

[0130] In the third type of downlink control channel detection capability described above, the terminal device can detect the downlink control channel and receive downlink control information on any n time-domain resources out of the first N time-domain resources on the second carrier, thereby enabling communication based on the scheduling of the downlink control information. In this case, if the Nn time-domain resources other than the n resources out of the first N time-domain resources are sufficient to complete carrier switching, then whether the switching interval is on the first carrier or the second carrier will not affect the terminal device's reception of downlink control information; if the Nn time-domain resources other than the n resources out of the first N time-domain resources are insufficient to complete carrier switching, then the network device determines that the switching interval is on the first carrier to avoid affecting the terminal device's successful reception of downlink control information.

[0131] Whether the Nn time-domain resources (excluding the first N time-domain resources) are sufficient to complete carrier handover can be determined based on the time-domain length of the handover interval of the terminal equipment. For example, if the time-domain length of the handover interval is greater than or equal to the length of Nn time-domain resources, then Nn time-domain resources are insufficient to complete carrier handover; conversely, if the time-domain length of the handover interval is less than the length of Nn time-domain resources, then Nn time-domain resources are sufficient to complete carrier handover.

[0132] For example, if a terminal device reports via RRC IE: "pdcch-MonitoringSingleSpanFirst4Sym-r16" that the detection timing it supports can be located on any three consecutive symbols within the first four symbols of a time slot, and the terminal device reports its supported handover interval as 35µs, then the terminal device can complete carrier handover in one symbol. The terminal device can then perform carrier handover in the first symbol of the time slot on the second carrier, and detect the downlink control channel on the second, third, and fourth symbols of that time slot. Correspondingly, the network device can transmit downlink control signals on the second, third, and fourth symbols. As another example, if a terminal device reports via RRC IE: "pdcch-MonitoringSingleSpanFirst4Sym-r16" that the detection timing it supports can be located on any three consecutive symbols within the first four symbols of a time slot, and the terminal device reports its supported handover interval as 140µs, then the terminal device cannot complete carrier handover in one symbol, and the terminal device can perform carrier handover on the first carrier.

[0133] When Nn time-domain resources are sufficient to complete carrier switching, see [reference needed]. Figure 7 As shown in (b), when the terminal device performs a carrier handover from CC1 to CC2 at the boundary of the first time unit, since Nn time-domain resources are sufficient to complete the carrier handover, meaning the handover interval does not overlap with the n time-domain resources, the network device can determine that the handover interval is in CC2, such as the first m time-domain resources of the second time unit on CC2, or it can determine that the handover interval is in CC1 (shown as a dashed line in the figure), such as the last m time-domain resources of the first time unit on CC1. It can be understood that the network device can transmit downlink control information on the last n time-domain resources of the N time-domain resources, while the terminal device performs carrier handover on the first Nn time-domain resources and receives downlink control information on the n time-domain resources via the second carrier. The carrier handover from CC2 to CC1 at the boundary of the third time unit is similar and will not be elaborated further for simplicity.

[0134] When Nn time-domain resources are insufficient to complete carrier switching, please refer to Figure 7As shown in (c), when the terminal device performs a carrier handover from CC1 to CC2 at the boundary of the first time unit, since the Nn time-domain resources are insufficient to complete the carrier handover, if the handover interval is CC2, it will overlap with the n time-domain resources for detecting the downlink control channel. In this case, the network device determines that the handover interval is CC1. If the handover interval is in the last m time-domain resources of the first time unit on CC1, it will avoid affecting the terminal device's reception of downlink control information. The carrier handover from CC2 to CC1 at the boundary of the third time unit is similar and will not be described further for simplicity.

[0135] In the above example, the downlink control channel detection capability of a terminal device determines that the handover interval being on the second carrier will affect the terminal device's reception of downlink control information. In this application embodiment, such downlink control channel capability is referred to as the first capability, which includes:

[0136] The supported downlink control channel detection timing is located within the first n time-domain resources of the time unit; or,

[0137] The detection timing of the supported downlink control channel is located in any n time domain resources among the first N time domain resources of the time unit, and the time domain length of the handover interval is greater than or equal to the length of Nn time domain resources.

[0138] In the above example, the downlink control channel detection capability of another terminal device determines that the handover interval can be on either the first carrier or the second carrier. In other words, under the scheduling of the network device, even if the handover interval is on the second carrier, it does not affect the terminal device's reception of downlink control information. This application refers to this downlink control channel capability as a second capability, which includes:

[0139] The detection timing of the supported downlink control channel is located at any time-domain resource within the time unit; or,

[0140] The detection timing of the supported downlink control channel is located in any n time domain resources among the first N time domain resources of the time unit, and the time domain length of the handover interval is less than the length of Nn time domain resources.

[0141] As mentioned earlier, under the second capability of the downlink control channel of the terminal device, the handover interval can be on the first carrier or the second carrier. In this case, the following are some possible examples of how to determine the position of the handover interval:

[0142] Example 1: The protocol stipulates that under the second capability of the downlink control channel of the terminal device, the handover interval is on the first carrier; or, the protocol stipulates that under the second capability of the downlink control channel of the terminal device, the handover interval is on the second carrier.

[0143] Example 2: Under the second capability of the downlink control channel of the terminal device, the network device configures the handover interval to be on the first carrier or the second carrier. Based on this, the network device can flexibly schedule the position of the handover interval and the resources of downlink control information. In the first example, when the detection timing of the downlink control channel supported by the terminal device is located on any time domain resource of the time unit, the network device can determine that the handover interval is on the second carrier, and transmit downlink control information on the time domain resources after the handover interval of the time unit on the second carrier; or, the network device can determine that the handover interval is on the first carrier, and transmit downlink control information on any time domain resource of the time unit on the second carrier. In the second example, when the detection timing of the downlink control channel supported by the terminal device is located on any n time domain resources among the first N time domain resources of the time unit, and the time domain length of the handover interval is less than the length of Nn time domain resources, the network device can determine that the handover interval is on the second carrier, and transmit downlink control information on the last n time domain resources among the N time domain resources; or, the network device can determine that the handover interval is on the first carrier, and transmit downlink control information on any n time domain resources among the N time domain resources on the second carrier.

[0144] Regarding the second example above, here is a possible distance: If the terminal device reports via RRC IE: "pdcch-MonitoringSingleSpanFirst4Sym-r16" that the detection timing supported by the terminal device can be located on any three consecutive symbols within the first four symbols of a time slot, and the terminal device reports its supported handover interval as 35µs, then the terminal device can complete the carrier handover in one symbol. The terminal device can perform carrier handover in the first symbol of the time slot on the second carrier, and detect the downlink control channel on the second, third, and fourth symbols of that time slot. Correspondingly, the network device can transmit downlink control signals on the second, third, and fourth symbols. Another example is that the terminal device, via RRC... IE: "pdcch-MonitoringSingleSpanFirst4Sym-r16" reports that the detection timing supported by the terminal device can be located on any 3 consecutive symbols within the first 4 symbols of a time slot, and when the terminal device reports that its supported handover interval is 140us, the terminal device cannot complete carrier handover in 1 symbol, and the terminal device can perform carrier handover on the first carrier.

[0145] Optionally, network devices can configure the handover interval via RRC signaling. See also Figure 8In step S320a, after the network device determines that the handover interval is on the first carrier or the second carrier, it can send a first RRC signaling to the terminal device to indicate the position of the handover interval. This embodiment uses configuring the handover interval via RRC signaling as an example, but it is not limited to this. For example, the network device can also indicate the position of the handover interval via downlink control information carried on the first carrier.

[0146] In some embodiments, the handover interval is also related to the carrier scheduling capability of the terminal device. The carrier scheduling capability is reflected in the carrier scheduling mode of the downlink control information supported by the terminal device. In an NR system, the carrier scheduling mode may include, for example, self-carrier scheduling, cross-carrier scheduling, or multi-carrier scheduling.

[0147] Self-carrier scheduling is a fundamental terminal equipment capability related to downlink control information scheduling. Specifically, the scheduling information within each cell is provided by the downlink control information transmitted within that cell. This self-carrier scheduling capability is supported by all terminal equipment as defined in the NR protocol and does not require terminal equipment to report this capability.

[0148] When a terminal device has a higher support capability for carrier scheduling modes, these enhanced terminal devices can report their capabilities. This application does not limit the signaling used by the terminal device when reporting capabilities. For example, the terminal device can report capabilities through RRC signaling, such as indicating the relevant capabilities of the carrier scheduling mode through RRC IE cells.

[0149] In cross-carrier scheduling scenarios, if RRC IE exists for example: "crossCarrierScheduling-SameSCS" (cross-carrier scheduling with the same subcarrier spacing), "crossCarrierScheduling-OtherSCS" (cross-carrier scheduling with different subcarrier spacings), or "crossCarrierSchedulingDL-DiffSCS-r16" (downlink cross-carrier scheduling with different subcarrier spacings in version 16), then the terminal device supports cross-carrier scheduling from PCell to SCell. That is, scheduling information on the SCell can be scheduled by DCI sent from the PCell. Similarly, if RRC IE exists for example: "crossCarrierSchedulingSCell-SpCellTypeB-r17" (cross-carrier scheduling of SCell based on primary serving cell type B in version 17) or "crossCarrierSchedulingSCell-SpCellTypeA-r17" (cross-carrier scheduling of SCell based on primary serving cell type A in version 17), then the terminal device supports cross-carrier scheduling from SCell to PCell. That is, scheduling information on the PCell can be scheduled by DCI sent from the SCell.

[0150] In multi-carrier scheduling scenarios, if RRC IE exists: “multiCell-PDSCH-DCI-1-3-DiffSCS-r18” (downlink control information for different subcarrier intervals of multi-cell PDSCH formats 1-3 in version 18), “multiCell-PDSCH-DCI-1-3-SameSCS-r18” (downlink control information for the same subcarrier interval of multi-cell PDSCH formats 1-3 in version 18), “multiCell-PUSCH-DCI-0-3-DiffSCS-r18” (downlink control information for different subcarrier intervals of multi-cell PUSCH formats 0-3 in version 18), or “multiCell-PUSCH-DCI-0-3-SameSCS-r18” (downlink control information for the same subcarrier interval of multi-cell PUSCH formats 0-3 in version 18), then the terminal device supports multi-carrier scheduling on the PCell, that is, the DCI transmitted on the PCell can simultaneously schedule the PCell and other SCells. In some other possible implementations, when the terminal device reports a terminal device capability for indicating multi-carrier scheduling on the SCell, it indicates that the DCI transmitted on the SCell can simultaneously schedule the SCell with other SCells and PCells.

[0151] This application uses the carrier scheduling support capability of the terminal equipment in the aforementioned NR system as an example for illustration, but does not limit it. The terminal equipment may also include support capabilities for other carrier scheduling modes, and may also report capabilities through other RRC cells; this application does not limit this.

[0152] In one possible example, when the terminal device supports cross-carrier scheduling or multi-carrier scheduling, the scheduling mode between PCell and SCell supported by the terminal device, or the scheduling between the primary carrier and the secondary carrier, can be summarized into the following two methods:

[0153] Method 1 supports scheduling of at least one secondary carrier by the primary carrier. In cross-carrier scheduling, the primary carrier can schedule secondary carriers; for example, downlink control information carried by the primary carrier can schedule data transmission resources in secondary carriers. In multi-carrier scheduling, the primary carrier can schedule two or more secondary carriers; for example, downlink control information carried by the primary carrier can schedule data transmission resources in two or more secondary carriers.

[0154] Method 2 supports scheduling of the primary carrier and / or at least one second secondary carrier by the first secondary carrier. In cross-carrier scheduling, the first secondary carrier can schedule either the primary carrier or the second secondary carrier. For example, downlink control information carried by the first secondary carrier can schedule data transmission resources in either the primary carrier or the second secondary carrier. In multi-carrier scheduling, the first secondary carrier can schedule the primary carrier and at least one second secondary carrier. For example, downlink control information carried by the first secondary carrier can schedule data transmission resources in both the primary carrier and at least one second secondary carrier. Here, the terms "first secondary carrier" and "second secondary carrier" are used to distinguish different secondary carriers, not as limiting designations. It can be understood that both the first and second secondary carriers can be collectively referred to as secondary carriers.

[0155] Based on the aforementioned carrier scheduling support capabilities, when the second carrier is the primary carrier in Method 1 or the first secondary carrier in Method 2, the second carrier carries downlink control information for cross-resource scheduling / multi-resource scheduling. Therefore, if the handover interval is on the second carrier, it may affect the terminal device's successful reception of the downlink control information. Thus, in cross-carrier scheduling / multi-carrier scheduling scenarios, the first capability of the aforementioned downlink control channel can include the following examples:

[0156] I. Supports scheduling of a primary carrier to at least one secondary carrier, with the second carrier being the primary carrier, and supports the detection timing of the downlink control channel located in the first n time domain resources of the time unit.

[0157] For example, in a cross-carrier scheduling scenario, the RRC IE reported by the terminal device is "crossCarrierScheduling-SameSCS", "crossCarrierScheduling-OtherSCS", or "crossCarrierSchedulingDL-DiffSCS-r16", indicating that the terminal device supports cross-carrier scheduling from PCell to SCell. Or, in a multi-carrier scheduling scenario, the RRC IE reported by the terminal device is "multiCell-PDSCH-DCI-1-3-DiffSCS-r18", "multiCell-PDSCH-DCI-1-3-SameSCS-r18", "multiCell-PUSCH-DCI-0-3-DiffSCS-r18", or "multiCell-PUSCH-DCI-0-3-SameSCS-r18", indicating that the terminal device supports multi-carrier scheduling on PCell. Based on this, if the second carrier is the primary carrier, that is, the scheduling information of the secondary carrier is scheduled by the downlink control information on the second carrier, the terminal device is considered to have the first capability of the downlink control channel.

[0158] Second, it supports scheduling of at least one secondary carrier by the primary carrier, with the second carrier being the primary carrier, and the detection timing of the downlink control channel is located in any n time-domain resources in the first N time-domain resources of the time unit, and the time-domain length of the switching interval is greater than or equal to the length of Nn time-domain resources.

[0159] For example, in a cross-carrier scheduling scenario, the RRC IE reported by the terminal device is "crossCarrierScheduling-SameSCS", "crossCarrierScheduling-OtherSCS", or "crossCarrierSchedulingDL-DiffSCS-r16", indicating that the terminal device supports cross-carrier scheduling from PCell to SCell. Alternatively, in a multi-carrier scheduling scenario, the RRC IE reported by the terminal device is "multiCell-PDSCH-DCI-1-3-DiffSCS-r18", "multiCell-PDSCH-DCI-1-3-SameSCS-r18", "multiCell-PUSCH-DCI-0-3-DiffSCS-r18", or "multiCell-PUSCH-DCI-0-3-SameSCS-r18", indicating that the terminal device supports multi-carrier scheduling on PCell. Furthermore, the RRC IE reported by the terminal device... The IE specification "pdcch-MonitoringSingleSpanFirst4Sym-r16" indicates that the terminal device supports downlink control channel detection timing, which can occur on any three consecutive symbols within the first four symbols of a time slot. For example, the detection timing can occur on the first three symbols of a time slot, or on the second, third, and fourth symbols of a time slot. Based on this, if the second carrier is the primary carrier, meaning the scheduling information of the secondary carrier is scheduled by the downlink control information on the second carrier, the terminal device is considered to have the first capability of the downlink control channel.

[0160] Third, it supports the scheduling of the primary carrier and / or at least one second secondary carrier by the first secondary carrier, and the second carrier is the first secondary carrier, and the detection timing of the downlink control channel is located in the first n time domain resources of the time unit.

[0161] For example, in a cross-carrier scheduling scenario, if the RRC IE reported by the terminal device is "crossCarrierSchedulingSCell-SpCellTypeB-r17" or "crossCarrierSchedulingSCell-SpCellTypeA-r17", then the terminal device supports cross-carrier scheduling of SCell to PCell. Based on this, if the second carrier is the first auxiliary carrier, that is, when the scheduling information of the primary carrier and / or at least one second auxiliary carrier is scheduled by the downlink control information on the second carrier, the terminal device is considered to have the first capability of the downlink control channel.

[0162] Fourth, it supports the scheduling of the primary carrier and / or at least one second secondary carrier by the first secondary carrier, and the second carrier is the first secondary carrier. Also, the detection timing of the downlink control channel is located in any n time domain resources in the first N time domain resources of the time unit, and the time domain length of the switching interval is greater than or equal to the length of Nn time domain resources.

[0163] For example, in a cross-carrier scheduling scenario, if the terminal device reports the RRC IE "crossCarrierSchedulingSCell-SpCellTypeB-r17" or "crossCarrierSchedulingSCell-SpCellTypeA-r17", then the terminal device supports cross-carrier scheduling of SCell to PCell. Furthermore, if the terminal device reports the RRC IE "pdcch-MonitoringSingleSpanFirst4Sym-r16", it indicates that the detection timing of the downlink control channel supported by the terminal device can be located on any three consecutive symbols within the first four symbols of a time slot, such as the first three symbols of a time slot or the second, third, and fourth symbols of a time slot. Based on this, if the second carrier is the first auxiliary carrier, meaning that the scheduling information of the primary carrier and / or at least one second auxiliary carrier is scheduled by the downlink control information on the second carrier, the terminal device is considered to have the first capability of the downlink control channel.

[0164] Based on the aforementioned carrier scheduling capabilities, when the second carrier is the auxiliary carrier in Mode 1, or the primary carrier or second auxiliary carrier in Mode 2, and the second carrier does not carry downlink control information, the handover interval can be on the second carrier. Of course, the handover interval can also be on the first carrier. That is, regardless of the detection capability of the terminal equipment for the downlink control channel, a handover interval on the second carrier does not affect the performance of the communication system.

[0165] In cross-carrier scheduling / multi-carrier scheduling scenarios, the second capability of the downlink control channel mentioned above can include the following examples:

[0166] Fifth, it supports scheduling of a primary carrier to at least one secondary carrier, with the second carrier being a secondary carrier, and supports the detection timing of the downlink control channel located in any time-domain resource of the time unit.

[0167] For example, in a cross-carrier scheduling scenario, the RRC IE reported by the terminal device is "crossCarrierScheduling-SameSCS", "crossCarrierScheduling-OtherSCS", or "crossCarrierSchedulingDL-DiffSCS-r16", indicating that the terminal device supports cross-carrier scheduling from PCell to SCell. Alternatively, in a multi-carrier scheduling scenario, the RRC IE reported by the terminal device is "multiCell-PDSCH-DCI-1-3-DiffSCS-r18", "multiCell-PDSCH-DCI-1-3-SameSCS-r18", "multiCell-PUSCH-DCI-0-3-DiffSCS-r18", or "multiCell-PUSCH-DCI-0-3-SameSCS-r18", indicating that the terminal device supports multi-carrier scheduling on PCell. Furthermore, the RRC IE reported by the terminal device... The IE (Internet Protocol version) specifies "pdcch-MonitoringAnyOccasions", "pdcch-MonitoringAnyOccasionsWithSpanGap", or "pdcch-MonitoringAnyOccasionsWithSpanGapCrossCarrierSch-r16", indicating that the detection timing of the downlink control channel supported by the terminal device can be located on any symbol within a time slot. Based on this, if the second carrier is a secondary carrier, meaning the scheduling information of the second carrier is scheduled by the downlink control information on the primary carrier, the terminal device is considered to have a second downlink control channel capability.

[0168] VI. Supports scheduling of at least one secondary carrier by the primary carrier, with the second carrier being a secondary carrier, and supports the detection timing of the downlink control channel located in any n time-domain resources among the first N time-domain resources of the time unit, and the time-domain length of the handover interval is less than the length of Nn time-domain resources.

[0169] For example, in a cross-carrier scheduling scenario, the RRC IE reported by the terminal device is "crossCarrierScheduling-SameSCS", "crossCarrierScheduling-OtherSCS", or "crossCarrierSchedulingDL-DiffSCS-r16", indicating that the terminal device supports cross-carrier scheduling from PCell to SCell. Alternatively, in a multi-carrier scheduling scenario, the RRC IE reported by the terminal device is "multiCell-PDSCH-DCI-1-3-DiffSCS-r18", "multiCell-PDSCH-DCI-1-3-SameSCS-r18", "multiCell-PUSCH-DCI-0-3-DiffSCS-r18", or "multiCell-PUSCH-DCI-0-3-SameSCS-r18", indicating that the terminal device supports multi-carrier scheduling on PCell. Furthermore, the RRC IE reported by the terminal device... The IE specification "pdcch-MonitoringSingleSpanFirst4Sym-r16" indicates that the terminal device supports downlink control channel detection timing, which can occur on any three consecutive symbols within the first four symbols of a time slot. For example, the detection timing can occur on the first three symbols of a time slot, or on the second, third, and fourth symbols of a time slot. Based on this, if the second carrier is a secondary carrier, meaning its scheduling information is scheduled by the downlink control information on the primary carrier, the terminal device is considered to have a second downlink control channel capability.

[0170] 7. Supports scheduling of the primary carrier and / or at least one second secondary carrier by the first secondary carrier, wherein the second secondary carrier is either the primary carrier or the second secondary carrier, and the detection timing of the supported downlink control channel is located in any time domain resource of the time unit.

[0171] For example, in a cross-carrier scheduling scenario, if the RRC IE reported by the terminal device is "crossCarrierSchedulingSCell-SpCellTypeB-r17" or "crossCarrierSchedulingSCell-SpCellTypeA-r17", then the terminal device supports cross-carrier scheduling of SCell to PCell. Furthermore, if the RRC IE reported by the terminal device is "pdcch-MonitoringAnyOccasions", "pdcch-MonitoringAnyOccasionsWithSpanGap", or "pdcch-MonitoringAnyOccasionsWithSpanGapCrossCarrierSch-r16", it indicates that the detection timing of the downlink control channel supported by the terminal device can be located on any symbol within a time slot. Based on this, if the second carrier is the primary carrier or the second secondary carrier, meaning the scheduling information of the second carrier is scheduled by the downlink control information on the first secondary carrier, then the terminal device is considered to have a second downlink control channel capability.

[0172] 8. Supports scheduling of the primary carrier and / or at least one second secondary carrier by the first secondary carrier, wherein the second secondary carrier is the primary carrier or the second secondary carrier, and the detection timing of the supported downlink control channel is located in any n time domain resources in the first N time domain resources of the time unit, and the time domain length of the handover interval is less than the length of Nn time domain resources.

[0173] For example, in a cross-carrier scheduling scenario, if the terminal device reports the RRC IE "crossCarrierSchedulingSCell-SpCellTypeB-r17" or "crossCarrierSchedulingSCell-SpCellTypeA-r17", then the terminal device supports cross-carrier scheduling of SCell to PCell. Furthermore, if the terminal device reports the RRC IE "pdcch-MonitoringSingleSpanFirst4Sym-r16", it indicates that the detection timing of the downlink control channel supported by the terminal device can be located on any three consecutive symbols within the first four symbols of a time slot, such as the first three symbols of a time slot or the second, third, and fourth symbols of a time slot. Based on this, if the second carrier is the primary carrier or the second secondary carrier, meaning the scheduling information of the second carrier is scheduled by the downlink control information on the first secondary carrier, then the terminal device is considered to have a second downlink control channel capability.

[0174] In cross-carrier / multi-carrier scheduling scenarios, under the following third capability of the downlink control channel, the handover interval being on the second carrier does not affect the performance of the communication system. This third capability can include the following examples:

[0175] 9. Supports scheduling of a primary carrier to at least one secondary carrier, where the second carrier is a secondary carrier, and supports the detection timing of the downlink control channel located in the first n time domain resources of the time unit.

[0176] 10. Supports scheduling of at least one secondary carrier by the primary carrier, with the second carrier being a secondary carrier, and supports the detection timing of the downlink control channel located in any n time-domain resources among the first N time-domain resources of the time unit, and the time-domain length of the switching interval is greater than or equal to the length of Nn time-domain resources.

[0177] 11. Supports scheduling of the primary carrier and / or at least one second secondary carrier by the first secondary carrier, wherein the second secondary carrier is either the primary carrier or the second secondary carrier, and the detection timing of the supported downlink control channel is located in the first n time domain resources of the time unit.

[0178] 12. Supports scheduling of the primary carrier and / or at least one second secondary carrier by the first secondary carrier, wherein the second secondary carrier is the primary carrier or the second secondary carrier, and the detection timing of the supported downlink control channel is located in any n time domain resources in the first N time domain resources of the time unit, and the time domain length of the switching interval is greater than or equal to the length of Nn time domain resources.

[0179] See Figure 7 In (d) of the diagram, in cross-carrier or multi-carrier scenarios, the terminal device supports carrier scheduling of CC1 to CC2. CC1 can be the primary carrier and CC2 can be the secondary carrier, or CC1 can be the secondary carrier and CC2 is the primary carrier, or both CC1 and CC2 can be secondary carriers. This application does not limit this. In multi-carrier scenarios, CC1 can also schedule other carriers besides CC2. When the detection timing of the downlink control channel supported by the terminal device is within the first n time domain resources of the time unit, when the terminal device performs a carrier handover from CC1 to CC2 at the boundary of the first time unit, since CC2 does not carry the downlink control channel, the network device can determine that the handover interval is CC2 or CC1 (shown as a dashed line in the figure). When the terminal device performs a carrier handover from CC2 to CC1 at the boundary of the third time unit, since the detection timing of the downlink control channel is within the first n time domain resources of the fourth time unit on CC1, a handover interval of CC1 would affect the terminal device's reception of downlink control information. Therefore, the network device determines that the handover interval is CC2.

[0180] In cross-carrier or multi-carrier scenarios, the correlation between the switching carrier being on the first or second carrier and the detection capability of the downlink control channel supported by the terminal device can be referred to the implementation logic of the aforementioned example, and will not be repeated here for the sake of brevity.

[0181] As mentioned earlier, under the third capability of the downlink control channel of the terminal device, the handover interval can be on the first carrier or the second carrier. In this case, the following possible implementation methods are given for determining the position of the handover interval:

[0182] In one implementation method, the protocol stipulates that the handover interval is on the first carrier under the third capability of the downlink control channel of the terminal device; or, the protocol stipulates that the handover interval is on the second carrier under the third capability of the downlink control channel of the terminal device.

[0183] In the second implementation method, under the third capability of the downlink control channel of the terminal device, the network device configures the handover interval to be on the first or second carrier. Based on this, the network device can flexibly schedule the position of the handover interval and the resources of downlink control information. For specific implementation details, please refer to the explanation in the aforementioned example; for brevity, it will not be repeated here.

[0184] Optionally, network devices can configure the handover interval via RRC signaling. See also Figure 8 In S320b, after the network device determines that the handover interval is on the first carrier or the second carrier, it can send a second RRC signaling to the terminal device to indicate the position of the handover interval. This application embodiment uses configuring the handover interval via RRC signaling as an example for illustration, but this application is not limited to this. For example, the network device can also indicate the position of the handover interval via downlink control information carried on the first carrier.

[0185] S220, the terminal device determines whether the handover interval is on the first carrier or the second carrier. Whether the handover interval is on the first carrier or the second carrier is related to the downlink control channel capability of the terminal device.

[0186] Terminal devices can determine whether the handover interval is on the first or second carrier in the same or similar way as network devices; for the sake of brevity, this will not be elaborated further.

[0187] In one possible implementation, if the terminal device determines the handover interval to be on the first carrier or the second carrier based on the capability of the downlink control channel, it will not affect the performance of the communication system. For example, if the terminal device is under the second or third capability of the downlink control channel, the handover interval can be determined to be on either the first carrier or the second carrier.

[0188] In this case, as an example of determining the location of the switching interval, the location of the switching interval can be agreed upon by the protocol, and the method of agreement can be found in the description of the aforementioned example.

[0189] As another example of determining the location of the handover interval, the location of the handover interval can be configured by the network device. See, for example, [link to relevant documentation]. Figure 8 In S320a, under the second capability of the downlink control channel of the terminal device, the terminal device can receive a first RRC signaling from the network device. The first RRC signaling is used to indicate the location of the handover interval, such as indicating that the handover interval is on the first carrier or the second carrier. Furthermore, in S330a, the terminal device can determine the location of the handover interval based on the first RRC signaling, such as by parsing the first RRC signaling to determine whether the handover interval is on the first carrier or the second carrier. See also, for example... Figure 8 In S320b, under the third capability of the downlink control channel of the terminal device, the terminal device can receive a second RRC signaling from the network device. The second RRC signaling is used to indicate the position of the handover interval, such as indicating that the handover interval is on the first carrier or the second carrier. Furthermore, in S330b, the terminal device can determine the position of the handover interval based on the second RRC signaling, such as determining whether the handover interval is on the first carrier or the second carrier by parsing the second RRC signaling.

[0190] This application uses the example of configuring the handover interval through RRC signaling to illustrate the embodiments, but this application does not limit it. For example, the network device can also indicate the position of the handover interval through the downlink control information carried by the first carrier.

[0191] This application does not limit the execution order between S210 and S220 above. Both network equipment and terminal equipment only need to determine whether the handover interval is on the first carrier or the second carrier before the carrier handover occurs.

[0192] S230, after the handover interval, the terminal equipment and network equipment communicate via a second carrier.

[0193] In one implementation, the handover interval is on the first carrier, meaning that the terminal device performs carrier switching within the current time unit on the first carrier, and after the handover interval, the terminal device communicates with the network device via the second carrier. In another implementation, the handover interval is on the second carrier, meaning that the terminal device communicates with the network device via the first carrier in the current time unit, performs carrier switching in the next time unit, and after the handover interval, the terminal device communicates with the network device via the second carrier.

[0194] The terminal device and the network device communicate via a second carrier, including the transmission of data and / or signaling via the second carrier, such as the transmission of downlink control information and uplink / downlink data scheduled by the downlink control information. In the embodiments of this application, the terminal device and the network device can perform uplink communication and / or downlink communication via the second carrier, and this application does not limit this.

[0195] Therefore, in this embodiment of the application, when the radio frequency unit of the terminal device performs carrier switching, the switching interval is related to the downlink control channel capability of the terminal device on the first carrier or the second carrier, which can avoid the impact of the switching interval on the downlink control channel on the second carrier, thereby improving the performance of the communication system.

[0196] Based on the above embodiments, when network devices and terminal devices determine whether the handover interval is on the first carrier or the second carrier based on the capabilities of the terminal device's downlink control channel, they can make the judgment based on the rules agreed upon in the protocol. For example, the protocol stipulates that: under the first capability of the terminal device's downlink control channel, the handover interval is on the first carrier; or, for another example, the protocol stipulates that: under the second or third capability of the terminal device's downlink control channel, the handover interval is on the first carrier or the second carrier, and the position of the handover interval is configured by RRC signaling.

[0197] In other embodiments, the network device can directly configure the handover interval location to the terminal device, as described below. Figure 9 The communication method 400 shown will be explained.

[0198] S410, the network device determines whether the handover interval is on the first carrier or the second carrier. Whether the handover interval is on the first carrier or the second carrier is related to the downlink control channel capability of the terminal device.

[0199] This step is the same as or similar to the implementation scheme of S210 in the previous example, and will not be repeated for the sake of brevity.

[0200] S420, the network device sends a third RRC signaling to the terminal device, which is used to indicate whether the handover interval is on the first carrier or the second carrier.

[0201] Correspondingly, the terminal device receives the third RRC signaling from the network device.

[0202] The network device indicates the position of the handover interval determined in S410 to the terminal device via third RRC signaling. For example, under the first capability of the terminal device's downlink control channel, the network device can indicate that the handover interval is on the first carrier via third RRC signaling; under the second or third capability of the terminal device's downlink control channel, the network device can flexibly schedule the position of the handover interval, such as indicating that the handover interval is on the first carrier via third RRC signaling, or indicating that the handover interval is on the second carrier via third RRC signaling, and this application does not limit this.

[0203] This application uses the example of configuring the handover interval through RRC signaling to illustrate the embodiments, but this application does not limit it. For example, the network device can also indicate the position of the handover interval through the downlink control information carried by the first carrier.

[0204] S430, the terminal device determines whether the handover interval is on the first carrier or the second carrier based on the third RRC signaling.

[0205] For example, if the third RRC signaling indicates that the handover interval is on the first carrier, the terminal device determines that the handover interval is on the first carrier by parsing the third RRC signaling; or if the third RRC signaling indicates that the handover interval is on the second carrier, the terminal device determines that the handover interval is on the second carrier by parsing the third RRC signaling.

[0206] In S440, terminal equipment and network equipment communicate via a second carrier after the handover interval.

[0207] S440 has the same or similar implementation as S230 above, and will not be described again for the sake of brevity.

[0208] In this embodiment, the position of the handover interval determined by the network device is related to the downlink control channel capability of the terminal device. This avoids the handover interval affecting the downlink control channel on the second carrier, thereby improving the performance of the communication system. Furthermore, the network device directly indicates to the terminal device whether the handover interval is on the first or second carrier, so that the terminal device can perform carrier switching at the corresponding position, which can reduce the processing complexity of the terminal device.

[0209] Based on the above embodiments, the network device and the terminal device can determine whether the handover interval is on the first carrier or the second carrier based on the downlink control channel capability of the terminal device. In further embodiments, the network device can determine the position of the handover interval based on the downlink control channel capability of the terminal device, and then indicate to the terminal device whether the handover interval is on the first carrier or the second carrier. If multiple terminal devices within a cell need to perform carrier handover, the network device needs to determine the position of the handover interval for each terminal device during carrier handover based on the capability of each terminal device. Therefore, in some possible implementations, the network device configures the position of the handover interval for terminal devices with different downlink control channel capabilities, resulting in greater scheduling difficulty and higher network device overhead.

[0210] Based on this, in this embodiment, the terminal device is mandatory to support one or more capabilities related to the downlink control channel. That is, when the terminal device is mandatory to support one or more capabilities related to the downlink control channel, the network device and the terminal device perform the process of determining the handover interval position as described in any of the foregoing embodiments, or the network device performs the process of determining and configuring the handover interval position as described in any of the foregoing embodiments. Here, "mandatory to support one or more capabilities related to the downlink control channel" can be described as "the terminal device supports one or more mandatory capabilities related to the downlink control channel." For terminal devices that do not support one or more mandatory capabilities related to the downlink control channel, the position of their handover interval may be uncertain, or these terminal devices may not perform carrier handover. In this case, the scheduling difficulty and overhead of the network device can be reduced. For example, the network device can determine the terminal device to perform carrier handover based on the capability information reported by the terminal device. If the capability information reported by the terminal device indicates that the terminal device supports a mandatory downlink control channel capability, the network device determines that the terminal device needs to perform carrier handover.

[0211] In one possible implementation, the capability information reported by the terminal device may include the downlink control channel capability as described in the preceding examples. For example, the mandatory or compulsory downlink control channel capability of the terminal device is any one of the following:

[0212] First, the supported downlink control channel detection timing is located in any n time domain resources within the first N time domain resources of a time unit. For example, the terminal device reports the supported detection timing via RRC IE: "pdcch-MonitoringSingleSpanFirst4Sym-r16", which can be located on any 3 consecutive symbols within the first 4 symbols of a time slot. For example, the first 3 symbols of a time slot; or, the 2nd, 3rd, and 4th symbols of a time slot.

[0213] Second, the supported downlink control channel detection timings can be located in any time domain resource within a time unit. For example, the terminal device can report the supported detection timings via RRC IE: "pdcch-MonitoringAnyOccasions" or "pdcch-MonitoringAnyOccasionsWithSpanGap" or "pdcch-MonitoringAnyOccasionsWithSpanGapCrossCarrierSch-r16", which can be located within any symbol of a time slot.

[0214] To further reduce the scheduling difficulty and overhead of network devices, in one possible implementation, in addition to the capability of the first or second downlink control channel in the above example, the capability of the terminal device to force or mandate the downlink control channel may also include the capability to support cross-carrier scheduling or the capability to support multi-carrier scheduling, that is: supporting the scheduling of the primary carrier to at least one secondary carrier; or supporting the scheduling of the first secondary carrier to the primary carrier and / or at least one second secondary carrier.

[0215] In another possible implementation, the capability information reported by the terminal device may include carrier switching capability based on a handover pattern. The handover pattern may, for example, indicate on which time domain resources the terminal device's radio frequency unit uses the first carrier for communication and on which time domain resources it uses the second carrier for communication. When the capability information reported by the terminal device indicates support for carrier switching based on a handover pattern, the network device can determine the handover interval when the terminal device performs carrier switching. When the capability information reported by the terminal device indicates that carrier switching based on a handover pattern is not supported, the network device may not determine the location of its handover interval for that terminal device, or in other words, the terminal device may not perform carrier switching. For example, the carrier switching capability based on the handover mode in the capability information reported by the terminal device can be associated with the downlink control channel capability of the terminal device. For example, the prerequisite capability for supporting carrier switching based on the handover mode is the aforementioned mandatory or required downlink control channel capability. That is, when the downlink control channel capability is the aforementioned mandatory or required downlink control channel capability, the capability information reported by the terminal device can include the capability supporting carrier switching based on the handover mode; when the downlink control channel capability is not the aforementioned mandatory or required downlink control channel capability, the carrier switching capability based on the handover mode is not reported.

[0216] In this embodiment, when the terminal device supports the capability of a mandatory or required downlink control channel, it is determined that when the radio frequency unit of the terminal device undergoes carrier switching, the switching interval is on the first carrier or the second carrier. It should be understood that the implementation logic for determining whether the switching interval is on the first carrier or the second carrier is the same as or similar to that in the aforementioned embodiments. For example, under the first capability of the terminal device's downlink control channel, the switching interval is on the first carrier; under the second or third capability of the terminal device's downlink control channel, the switching interval is configured by the network device. The difference is that the first capability, second capability, and third capability in this embodiment do not include the capability of the terminal device's basic downlink control channel. The capability of the basic downlink control channel may, for example, include the detection timing of the supported downlink control channel being located in the first n time domain resources of the time unit. Alternatively, the first capability, second capability, and third capability in this embodiment do not include the terminal device's self-carrier scheduling capability.

[0217] The first capability of the downlink control channel of the terminal device may include, for example:

[0218] The detection timing of the supported downlink control channel is located in any n time domain resources among the first N time domain resources of the time unit, where N is greater than n, and the time domain length of the handover interval is greater than or equal to the length of Nn time domain resources.

[0219] The primary capability of the downlink control channel of the terminal device may also include, for example:

[0220] Supports scheduling of the primary carrier to at least one secondary carrier, with the second carrier being the primary carrier; or,

[0221] It supports scheduling of the primary carrier and / or at least one second secondary carrier by the first secondary carrier, wherein the second carrier is the first secondary carrier.

[0222] The second capability of the downlink control channel of the terminal device may include, for example:

[0223] The detection timing of the supported downlink control channel is located at any time-domain resource within the time unit; or,

[0224] The detection timing of the supported downlink control channel is located in any n time domain resources among the first N time domain resources of the time unit, where N is greater than n, and the time domain length of the handover interval is less than the length of Nn time domain resources.

[0225] The second capability of the downlink control channel of the terminal device may also include, for example:

[0226] Supports scheduling of the primary carrier to at least one secondary carrier, with the second carrier being the primary carrier; or,

[0227] It supports scheduling of the primary carrier and / or at least one second secondary carrier by the first secondary carrier, wherein the second carrier is the first secondary carrier.

[0228] The third capability of the downlink control channel of the terminal device may include, for example:

[0229] Supports scheduling of the primary carrier to at least one secondary carrier, where the second carrier is a secondary carrier; or,

[0230] Supports scheduling of the primary carrier and / or at least one second secondary carrier by the first secondary carrier, wherein the second carrier is either the primary carrier or the second secondary carrier;

[0231] as well as,

[0232] The detection timing of the supported downlink control channel is located in any n time domain resources among the first N time domain resources of the time unit, where N is greater than n, and the time domain length of the handover interval is greater than or equal to the length of Nn time domain resources.

[0233] The capabilities described above have been explained in the foregoing embodiments and will not be repeated here for the sake of brevity.

[0234] In the various embodiments of this application, unless otherwise specified or in case of logical conflict, the terminology and / or descriptions between the various embodiments are consistent and can be referenced by each other. Technical features in different embodiments can be combined to form new embodiments according to their inherent logical relationships.

[0235] The methods provided in the embodiments of this application have been described in detail above with reference to several accompanying drawings. The apparatus provided in the embodiments of this application will now be described with reference to the accompanying drawings.

[0236] Figures 10 to 12 The diagram illustrates the possible structures of communication devices provided in the embodiments of this application. These communication devices can be used to implement the functions of terminal devices or network devices in the above method embodiments, and thus can also achieve the beneficial effects of the above method embodiments. In the embodiments of this application, the communication device can be a terminal device, a network device, or a module (such as a chip) applied to a terminal device or a network device.

[0237] like Figure 10 As shown, the communication device 500 includes a processing module 510 and a transceiver module 520. The communication device 500 is used to implement the functions of the terminal device and the network device in any of the above method embodiments.

[0238] When the communication device 500 implements the functions of the terminal device: the processing module 510 can be used to determine whether the switching interval is on the first carrier or the second carrier. The switching interval includes the time occupied by the working carrier of the radio frequency unit switching from the first carrier to the second carrier. Whether the switching interval is on the first carrier or the second carrier is related to the downlink control channel capability of the terminal device. The transceiver module 520 can be used to communicate via the second carrier after the switching interval.

[0239] When the communication device 500 is used to implement the functions of a network device: the processing module 510 can be used to determine whether the handover interval is on the first carrier or the second carrier. The handover interval includes the time occupied by the working carrier of the radio frequency unit switching from the first carrier to the second carrier. Whether the handover interval is on the first carrier or the second carrier is related to the downlink control channel capability of the terminal device. The transceiver module 520 can be used to communicate via the second carrier after the handover interval.

[0240] For a more detailed description of the processing module 510 and the transceiver module 520, please refer to the relevant descriptions in the above method embodiments.

[0241] Optionally, the processing module 510 may be a processor or controller, such as a central processing unit (CPU), a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. It can implement or execute the various exemplary logic blocks, modules, and circuits described in conjunction with the disclosure of this application. The processor may also be a combination that implements computing functions, such as including one or more microprocessor combinations, a combination of a DSP and a microprocessor, etc. The transceiver module 520 may be a transceiver, interface circuit, bus, pin, or other possible communication interface for receiving signals from other devices. For example, when the device is implemented as a chip, the transceiver module 520 is an interface circuit for the chip to receive signals from other chips or devices, or an interface circuit for the chip to send signals to other chips or devices. Optionally, the communication device may also include a storage module for storing device program code and / or data, and the processing module 510 and / or transceiver module 520 may interact with the storage module.

[0242] like Figure 11 As shown, the communication device 600 includes a processor 610 and an interface circuit 620. The processor 610 and the interface circuit 620 are coupled to each other. It is understood that the interface circuit 620 can be a transceiver or an input / output interface. Optionally, the communication device 600 may also include a memory 630 for storing instructions executed by the processor 610, or storing input data required for the processor 610 to execute instructions, or storing data generated after the processor 610 executes instructions. Sometimes, the interface circuit 620 can also be understood as part of the processor 610, in which case the communication device 600 includes the processor 610.

[0243] When the communication device 600 is used to implement the method in the above embodiments, the processor 610 is used to implement the function of the processing module 610, and the interface circuit 620 is used to implement the function of the transceiver module 620.

[0244] When the aforementioned communication device is a chip applied to a terminal, the terminal chip implements the functions of the terminal device in the above method embodiments. The terminal chip receives information from the network device, which can be understood as the information being first received by other modules (such as an RF module or antenna) in the terminal device, and then sent to the terminal chip by these modules. The terminal chip sends information to the network device, which can be understood as the information being first sent to other modules (such as an RF module or antenna) in the terminal device, and then sent to the network device by these modules.

[0245] When the aforementioned communication device is a chip used in a network device, the chip implements the functions of the network device in the above method embodiments. The chip receives information from the terminal device, which can be understood as the information being first received by other modules (such as an RF module or antenna) in the network device, and then sent to the chip by these modules. The chip sends information to the terminal device, which can be understood as the information being first sent to other modules (such as an RF module or antenna) in the network device, and then sent to the terminal device by these modules.

[0246] Figure 12 This is a schematic diagram of the network device provided in the embodiments of this application, for example, a schematic diagram of a base station. The base station 700 can be applied to, for example... Figure 1In the system shown, the functions of the network devices described in the above method embodiments are executed. As shown in the figure, the base station 700 may include one or more of the following: one or more (DU+RU) 710s and one or more CUs 720s. The CU 720 can communicate with the next-generation core network. The DU may include at least one antenna 711, at least one radio frequency unit 712, at least one processor 713, and at least one memory 714. The DU is mainly used for transmitting and receiving radio frequency signals, converting radio frequency signals to baseband signals, and performing some baseband processing. The CU 720 may include at least one processor 722 and at least one memory 721. The CU 720 and the DU can communicate through an interface. The control plane (CP) interface can be Fs-C, such as F1-C, and the user plane (UP) interface can be Fs-U, such as F1-U. The DU and RU can cooperate to implement the functions of the physical (PHY) layer. A DU can be connected to one or more RUs. The functions of the DU and RU can be configured in various ways according to the design. For example, a DU is configured to implement baseband functions, and an RU is configured to implement mid-RF functions. As another example, a DU is configured to implement higher-level functions in the PHY layer, and an RU is configured to implement lower-level and RF functions in the PHY layer. Higher-level functions in the PHY layer may include a portion of the PHY layer's functionality closer to the MAC layer, while lower-level functions in the PHY layer may include another portion of the PHY layer's functionality closer to the mid-RF side.

[0247] The CU 720 serves as the control center for the base station and can correspond to... Figure 10 The processing unit or Figure 11 The processor in the unit, also known as a processing unit, is mainly used to perform baseband processing functions. For example, the CU 720 can be used to control the base station to execute the operation procedures of the network device described in the above method embodiments.

[0248] Alternatively, the base station 700 may include one or more radio frequency units (RUs), one or more DUs, and one or more CUs. A DU may include at least one processor 713 and at least one memory 714, an RU may include at least one antenna 711 and at least one radio frequency unit 712, and a CU may include at least one processor 722 and at least one memory 721.

[0249] In one example, the CU 720 can be composed of one or more boards. These boards can collectively support a single access-indicating radio access network (such as a 5G network), or they can each support radio access networks with different access standards (such as LTE, 5G, or other networks). The memory 721 and processor 722 can serve one or more boards. That is, each board can have its own memory and processor, or multiple boards can share the same memory and processor. Furthermore, each board can also have necessary circuitry. Similarly, the DU can be composed of one or more boards. These boards can collectively support a single access-indicating radio access network (such as a 5G network), or they can each support radio access networks with different access standards (such as LTE, 5G, or other networks). The memory 714 and processor 713 can serve one or more boards. That is, each board can have its own memory and processor, or multiple boards can share the same memory and processor. Furthermore, each board can also have necessary circuitry.

[0250] It should be understood that Figure 12 The base station 700 shown can implement the various processes involved in the network device in the method embodiments. The operation and / or function of each module in the base station 700 are respectively for implementing the corresponding processes in the above method embodiments. For details, please refer to the description in the above method embodiments; to avoid repetition, detailed descriptions are appropriately omitted here.

[0251] It should be understood that Figure 12 The base station 700 shown is merely one possible architecture for network devices and should not be construed as limiting this application. The method provided in this application can be applied to network devices with other architectures, such as network devices including CU, DU, and AAU. This application does not limit the specific architecture of the network device.

[0252] It should be understood that Figure 12 This is for illustrative purposes only and not a limitation; network devices may not rely on this. Figure 12 The structure shown is different. For example, a network device may also include an AAU, a CU, and / or a DU, or a BBU and an adaptive radio unit (ARU). This application does not limit this.

[0253] The aforementioned CU and / or DU can be used to perform the actions implemented internally by the network device as described in the preceding method embodiments, while the AAU can be used to perform the actions described in the preceding method embodiments whereby the network device sends data to the terminal or the terminal receives data from the network device. Please refer to the descriptions in the preceding method embodiments for details, which will not be repeated here.

[0254] In this application, entity A sends information to entity B, either directly or indirectly through other entities. Similarly, entity B receives information from entity A, either directly or indirectly through other entities. Entities A and B can be RAN nodes or terminals, or modules within RAN nodes or terminals. Information transmission and reception can be between RAN nodes and terminals, such as between a base station and a terminal; between two RAN nodes, such as between a CU and a DU; or between different modules within a single device, such as between a terminal chip and other modules of the terminal, or between a base station chip and other modules of the base station.

[0255] It is understood that the processor in the embodiments of this application can be a central processing unit, or other general-purpose processors, digital signal processors, application-specific integrated circuits, field-programmable gate arrays, or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. A general-purpose processor can be a microprocessor or any conventional processor.

[0256] The method steps in the embodiments of this application can be implemented in hardware or in software instructions executable by a processor. The software instructions can consist of corresponding software modules, which can be stored in random access memory, flash memory, read-only memory, programmable read-only memory, erasable programmable read-only memory, electrically erasable programmable read-only memory, registers, hard disks, portable hard disks, compact disc read-only memory (CD-ROM), or any other form of storage medium well known in the art. An exemplary storage medium is coupled to a processor, enabling the processor to read information from and write information to the storage medium. The storage medium can also be a component of the processor. The processor and storage medium can reside in an application-specific integrated circuit (ASIC). Alternatively, the ASIC can reside in a base station or terminal. The processor and storage medium can also exist as discrete components in a base station or terminal.

[0257] In the above embodiments, implementation can be achieved entirely or partially through software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented entirely or partially in the form of a computer program product. The computer program product includes one or more computer programs or instructions. When the computer program or instructions are loaded and executed on a computer, the processes or functions described in the embodiments of this application are performed entirely or partially. The computer can be a general-purpose computer, a special-purpose computer, a computer network, a network device, a terminal device, or other programmable device. The computer program or instructions can be stored in a computer-readable storage medium or transferred from one computer-readable storage medium to another. For example, the computer program or instructions can be transferred from one website, computer, server, or data center to another website, computer, server, or data center via wired or wireless means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium, such as a floppy disk, hard disk, or magnetic tape; it can also be an optical medium, such as a digital video optical disc; or it can be a semiconductor medium, such as a solid-state drive. The computer-readable storage medium may be a volatile or non-volatile storage medium, or may include both types of storage media.

Claims

1. A communication method, characterized in that, include: The handover interval is determined to be on the first carrier or the second carrier. The handover interval includes the time occupied by the working carrier of the radio frequency unit when it is switched from the first carrier to the second carrier. The handover interval being on the first carrier or the second carrier is related to the downlink control channel capability of the terminal device. After the switching interval, communication is conducted via the second carrier.

2. The method according to claim 1, characterized in that, The switching interval is related to the downlink control channel capability of the first or second carrier and the terminal device, including: Under the first capability of the downlink control channel of the terminal device, the handover interval is within the first carrier; wherein... The first capability includes: The supported downlink control channel detection timing is located within the first n time-domain resources of the time unit; or, The detection timing of the supported downlink control channel is located in any n time domain resources among the first N time domain resources of the time unit, where N is greater than n, and the time domain length of the switching interval is greater than or equal to the length of Nn time domain resources.

3. The method according to claim 2, characterized in that, The first capability also includes: Supports scheduling of a primary carrier to at least one secondary carrier, wherein the second carrier is the primary carrier; or, It supports scheduling of the primary carrier and / or at least one second secondary carrier by the first secondary carrier, wherein the second secondary carrier is the first secondary carrier.

4. The method according to claim 1, characterized in that, Under the second capability of the downlink control channel of the terminal device, the method further includes: Sending or receiving a first Radio Resource Control (RRC) signaling message, wherein the first RRC signaling message indicates that the handover interval is on the first carrier or the second carrier; wherein... The second capability includes: The detection timing of the supported downlink control channel is located at any time-domain resource within the time unit; or, The detection timing of the supported downlink control channel is located in any n time domain resources among the first N time domain resources of the time unit, where N is greater than n, and the time domain length of the switching interval is less than the length of Nn time domain resources.

5. The method according to claim 1, characterized in that, Under the third capability of the downlink control channel of the terminal device, the method further includes: Sending or receiving a second RRC signaling, the second RRC signaling indicating that the handover interval is on the first carrier or the second carrier; wherein... The third capability includes: Supports scheduling of a primary carrier to at least one secondary carrier, wherein the second carrier is the secondary carrier; or, Supports scheduling of a first secondary carrier to a primary carrier and / or at least one second secondary carrier, wherein the second carrier is either the primary carrier or the second secondary carrier; as well as, The supported downlink control channel detection timing is located within the first n time-domain resources of the time unit; or, The detection timing of the supported downlink control channel is located in any n time domain resources among the first N time domain resources of the time unit, where N is greater than n, and the time domain length of the switching interval is greater than or equal to the length of Nn time domain resources.

6. The method according to any one of claims 1 to 3, characterized in that, Determining whether the switching interval is on the first carrier or the second carrier includes: The handover interval is determined to be on the first carrier or the second carrier based on the downlink control channel capability of the terminal device.

7. The method according to any one of claims 1 to 3 and 6, characterized in that, When applied to the terminal device side, determining whether the switching interval is on the first carrier or the second carrier includes: Receive third RRC signaling, the third RRC signaling being used to configure the handover interval; Based on the third RRC signaling, it is determined that the switching interval is on the first carrier or the second carrier.

8. The method according to any one of claims 1 to 3, 6, characterized in that, Applied to the network device side, it also includes: Send a third RRC signaling message, which is used to configure the handover interval.

9. The method according to claim 1, characterized in that, The required downlink control channel capabilities of the terminal device include: The supported downlink control channel detection timing is located in any n time-domain resources within the first N time-domain resources of the time unit, where N is greater than n; or, The detection timing of the supported downlink control channel is located at any time domain resource within the time unit.

10. The method according to claim 9, characterized in that, The mandatory downlink control channel capability of the terminal device also includes: Supports scheduling of the primary carrier to at least one secondary carrier; or, It supports scheduling of the primary carrier and / or at least one second secondary carrier by the first secondary carrier.

11. A communication device, characterized in that, Includes units for performing the method as described in any one of claims 1 to 10.

12. A communication device, characterized in that, It includes one or more processors, said one or more processors being configured to execute computer programs or instructions in memory, causing said communication device to perform the method as described in any one of claims 1 to 8.

13. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it causes the method as described in any one of claims 1 to 10 to be performed.

14. A computer program product, characterized in that, Includes a computer program that, when run, causes the method as described in any one of claims 1 to 10 to be performed.

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