Cell activation method and communication device

Abstract

The present application provides a cell activation method and a communication device, which may be applied to scenarios such as carrier aggregation, and is particularly applicable to activating a high-frequency secondary cell. The method includes receiving first configuration information from a network device via a first cell, where the first configuration information indicates N time-frequency resources in a one-to-one correspondence with N temporary reference signals (TRSs); receiving K of the N TRSs on K of the N time-frequency resources; and further activating a second cell based on the K TRSs. Compared to activating a cell by using a physical broadcast channel block (SSB), configuring a dedicated TRS for a terminal device can reduce the delay in activating the secondary cell.

Description

[Technical Field]

[0001] The present application relates to the field of communication technologies, and more particularly to a cell activation method and communication device. [Background technology]

[0002] This application claims priority to Chinese Patent Application No. 202211589773.9, entitled "CELL ACTIVATION METHOD AND COMMUNICATION APPARATUS," filed with the State Intellectual Property Office of the People's Republic of China on December 12, 2022, which is incorporated herein by reference in its entirety.

[0003] Two or more component carriers (CCs) can be aggregated by using carrier aggregation (CA) to support a larger transmission bandwidth. In this way, the requirements for increasing the peak rate of a single user and the system capacity can be met. When CA technology is applied, a terminal device can communicate with a primary cell (PCell) and a secondary cell (SCell) simultaneously. An SCell can perform data transmission only when the SCell is in an activated state.

[0004] Currently, for cell activation, time-frequency synchronization between a network device and a terminal device must first be accomplished via a synchronization signal and physical broadcast channel block (SSB). To reduce network power consumption and system overhead, a long SSB transmission period is usually configured. However, a long SSB transmission period causes a long cell activation delay, which affects the user experience and increases the power consumption of the terminal device. [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] 3GPP technical specification (TS) 38.101-1 V17.7.0 [Non-patent document 2] 3GPP TS 38.133 V17.7.0 Summary of the Invention

[0006] The present application provides a cell activation method and a communication device for reducing the delay in activating a secondary cell.

[0007] According to a first aspect, there is provided a cell activation method, which is executed by a terminal device or a module used in the terminal device, and includes the steps of receiving first configuration information from a network device via a first cell, where the first configuration information indicates N time-frequency resources in a one-to-one correspondence with N temporary reference signals (TRSs), where the N time-frequency resources are used to carry the N TRSs, respectively, receiving K of the N TRSs on K of the N time-frequency resources, where K and N are positive integers and K≦N, and activating a second cell based on the K TRSs.

[0008] In some implementations of the first aspect, the first configuration information is carried in radio resource control (RRC) signaling.

[0009] According to the above technical solution, in the present application, a TRS is transmitted on a dedicated time-frequency resource independently configured for a terminal device to activate a cell. This allows personalized configuration of parameters such as the period and / or transmission time of the TRS. Compared with activating a cell via a common SSB, the delay in activating a secondary cell can be reduced, thereby allowing the terminal device to quickly activate the cell, improving the user experience and reducing the power consumption of the terminal device.

[0010] In some implementations of the first aspect, a communication connection is established between the first cell and the terminal device, for example, the first cell may be a primary cell of the terminal device.

[0011] In this implementation, the first cell may be a low-frequency primary cell. For example, the frequency range of the first cell may be frequency range 1 (FR1). The second cell may be a secondary cell of the terminal device.

[0012] In this implementation, the second cell is a high-frequency secondary cell, for example, the frequency range of the second cell may be frequency range 2 (FR2).

[0013] Based on the above setting, the solution in this application can be effectively applied to the activation process of high frequency cells.

[0014] In some implementations of the first aspect, each of the N TRSs includes a primary synchronization signal PSS and / or a secondary synchronization signal SSS.

[0015] In a possible implementation, the first symbol used to carry the PSS and the second symbol used to carry the SSS are in the same slot, and the first and second symbols may be two consecutive symbols.

[0016] In the present application, in some implementations of the first aspect, the TRS includes a PSS, an SSS, and a physical broadcast channel (PBCH).

[0017] In some implementations of the first aspect, the largest time gap between any two adjacent time-frequency resources in the time domain among the N time-frequency resources is the first time gap, and the largest time gap between any two adjacent time-frequency resources in the time domain among the plurality of time-frequency resources used to carry SSBs is the second time gap, and the first time gap is shorter than the second time gap.

[0018] In some implementations of the first aspect, when N time-frequency resources are configured, the value of N is less than or equal to the maximum number of beams supported by the second cell.

[0019] In some implementations of the first aspect, first activation information is received from the network device, and the first activation information may indicate to activate the second cell. The first activation information may be medium access control-control element (MAC CE) signaling.

[0020] In some implementations of the first aspect, first indication information from a network device is received, and the first indication information indicates K of the N TRSs. The N TRSs may be understood as a TRS pool configured for the terminal device by the network device to be used for selection, and the K TRSs may be understood as TRSs that the network device indicates to the terminal device to actually use in the process of activating the second cell. In a possible implementation, the first indication information and the first activation information may be carried in the same signaling.

[0021] In some implementations of the first aspect, there is a third time gap between the time-frequency resource used to carry the TRS having the leading time-domain position among the K TRSs and the time-frequency resource used to carry the first activation information, where the third time gap is configured by signaling or predefined in a protocol. In possible cases, the duration from the start of receiving the first activation information to the completion of receiving the TRS having the trailing time-domain position among the K TRSs is shorter than a first threshold. The first threshold is the time from the start of receiving the second activation information to the completion of receiving the SSB having the trailing time-domain position among the K SSBs, where the second activation information is activation information received when the second cell is activated via the K SSBs.

[0022] In other words, the first duration is shorter than the second duration, the first duration is the duration from the start of receiving the first activation information to the completion of receiving the TRS having the tailmost time-domain position among the K TRSs, and the second duration is the duration from the start of receiving the second activation information to the completion of receiving the SSB having the tailmost time-domain position among the N SSBs, where the N SSBs are used to activate the second cell, and the first activation information and the second activation information indicate to activate the second cell.

[0023] In addition, the K TRSs belong to one of a plurality of TRS burst sets, and there is a fourth time gap between two adjacent TRS burst sets in the time domain, the fourth time gap being shorter than the fifth time gap, and the fifth time gap being the time gap between two adjacent SSB burst sets in the time domain in the plurality of SSB burst sets.

[0024] Therefore, compared with activating a cell via SSB, in this application, activating a cell by using TRS with a shorter transmission duration can reduce the activation delay, which improves the user experience and reduces the power consumption of the terminal device.

[0025] According to a second aspect, there is provided a cell activation method, executed by a network device or a module used in the network device, comprising: transmitting first configuration information through a first cell, the first configuration information indicating N time-frequency resources in a one-to-one correspondence with N temporary reference signals (TRS), each of the N time-frequency resources being used to carry the N TRS; and transmitting K of the N TRSs on K of the N time-frequency resources, the K TRSs being used to activate a second cell, where K and N are positive integers and K≦N.

[0026] In some implementations of the second aspect, the first cell is a primary cell of the terminal device, and the second cell is a secondary cell of the terminal device.

[0027] In some implementations of the second aspect, the first configuration information is carried in radio resource control (RRC) signaling. In other words, the N time-frequency resources are dedicated resources configured for the terminal device by the network device, and different terminal devices in the first cell receive the N TRSs by using corresponding different time-frequency resources.

[0028] According to the above technical solution, in the present application, a TRS can be transmitted on a dedicated time-frequency resource to activate a cell, which can reduce the delay in activating a secondary cell, so that the terminal device can quickly activate the cell, improve the user experience, and reduce the power consumption of the terminal device.

[0029] In some implementations of the second aspect, each of the N TRSs includes a primary synchronization signal (PSS) and a secondary synchronization signal (SSS), and the first symbol used to carry the PSS and the second symbol used to carry the SSS are in the same slot. Furthermore, the first symbol and the second symbol are two consecutive symbols.

[0030] In the present application, in some implementations of the second aspect, the TRS includes a PSS and an SSS, and further includes a PBCH.

[0031] In some implementations of the second aspect, the TRS in the present application may include only a PSS or only an SSS.

[0032] In some implementations of the second aspect, the largest time gap between any two adjacent time-frequency resources in the time domain among the N time-frequency resources is the first time gap, and the largest time gap between any two adjacent time-frequency resources in the time domain among the plurality of time-frequency resources used to carry SSB is the second time gap, and the first time gap is shorter than the second time gap.

[0033] In some implementations of the second aspect, when N time-frequency resources are configured, the value of N is less than or equal to the maximum number of beams supported by the second cell.

[0034] In some implementations of the second aspect, first activation information is received from a network device, and the first activation information may indicate to activate the second cell.

[0035] In some implementations of the second aspect, first indication information is transmitted, and the first indication information indicates K of the N TRSs. In possible implementations, the first indication information and the first activation information may be carried in the same signaling, for example, both may be carried in MAC CE signaling.

[0036] In some implementations of the second aspect, there is a third time gap between the time-frequency resource used to carry the TRS having the leading time-domain position among the K TRSs and the time-frequency resource used to carry the first activation information, where the third time gap is configured by using signaling or predefined in a protocol. Furthermore, a duration from the start of transmitting the first activation information to the completion of transmitting the TRS having the trailing time-domain position among the K TRSs is shorter than a first threshold. The first threshold is the time from the start of transmitting the second activation information to the completion of transmitting the SSB having the trailing time-domain position among the K SSBs, where the second activation information is activation information transmitted when the second cell is activated via the K SSBs.

[0037] The TRS is configured to be transmitted at a time period shorter than a first threshold, thereby reducing activation delay, improving user experience and reducing power consumption of the terminal device.

[0038] In some implementations of the second aspect, the K TRSs belong to one of a plurality of TRS burst sets, and there is a fourth time gap between two adjacent TRS burst sets in the time domain, the fourth time gap being shorter than the fifth time gap, and the fifth time gap being the time gap between two adjacent SSB burst sets in the time domain in the plurality of SSB burst sets. Since the fourth time gap in the present application is shorter than the fifth time gap, the TRS period configured in the present application may be shorter than the SSB period.

[0039] According to the above solution, a short TRS transmission period can be configured for a specific terminal device to reduce the time the terminal device waits to receive a TRS in the activation process, which helps reduce delays in the activation procedure and improve user experience.

[0040] According to a third aspect, there is provided a communications device including a processor, the processor configured to execute a computer program stored in a memory to enable the communications device to perform a method according to the first or second aspect.

[0041] According to a fourth aspect, there is provided a computer-readable storage medium having stored thereon a computer program or instructions which, when executed by a communications device, enables the communications device to perform a method provided in the first or second aspect.

[0042] According to a fifth aspect, there is provided a chip including a processor, the chip configured to execute a computer program stored in a memory to enable a communications device in which the chip system is installed to perform a method according to the first or second aspect.

[0043] According to a sixth aspect, there is provided a computer program which, when executed by a communications device, performs a method according to the first or second aspect. [Brief explanation of the drawings]

[0044] [Figure 1] 1 is a diagram of a communication system applicable to embodiments of the present application; [Figure 2] 1 is a diagram of an application scenario applicable to embodiments of the present application; [Figure 3] FIG. 1 is a diagram of the beam sweeping process. [Figure 4] 1 is a schematic interaction flowchart applicable to embodiments of the present application; [Figure 5] FIG. 10 illustrates an example of a TRS burst pattern according to an embodiment of the present application. [Figure 6] FIG. 10 illustrates another example of a TRS burst according to an embodiment of the present application. [Figure 7] FIG. 10 illustrates yet another example of a TRS burst pattern according to an embodiment of the present application. [Figure 8] FIG. 10 illustrates yet another example of a TRS burst pattern according to an embodiment of the present application. [Figure 9] FIG. 1 illustrates a TRS transmission method according to an embodiment of the present application. [Figure 10] FIG. 10 illustrates another TRS transmission method according to an embodiment of the present application. [Figure 11] FIG. 1 is a diagram of a set of multiple TRS bursts. [Figure 12] 1 is a diagram of a set of multiple SSB bursts. [Figure 13] 1 is a diagram of a communication device according to an embodiment of the present application; [Figure 14] FIG. 2 is a diagram of another communication device according to an embodiment of the present application. DETAILED DESCRIPTION OF THE INVENTION

[0045] FIG. 1 is a diagram of an architecture of a communication system 100 applicable to an embodiment of the present application. As shown in FIG. 1, the communication system includes a radio access network 100 and a core network 200. Optionally, the communication system 100 may further include the Internet 300. The radio access network 100 may include at least one radio access network device (e.g., 110a and 110b in FIG. 1) and may further include at least one terminal device (e.g., 120a to 120j in FIG. 1). The terminal device is connected to the radio access network device in a wireless manner, and the radio access network device is connected to the core network in a wireless or wired manner. The core network device and the radio access network device may be independent and separate physical devices, or the functions of the core network device and the logical functions of the radio access network device are integrated into the same physical device, or some functions of the core network device and some functions of the radio access network device are integrated into one physical device. A wired or wireless manner may be used for connections between terminals and between radio access network devices.

[0046] It should be understood that Figure 1 is merely an illustration, and the communication system may further include other network devices, such as wireless relay devices and wireless backhaul devices, which are not shown in Figure 1.

[0047] A radio access network device is an access device for a terminal device to wirelessly access a communication system and is sometimes referred to as a network device. The network device may be a base station, an evolved NodeB (eNodeB), a transmission reception point (TRP), a next generation NodeB (gNB) in a 5G mobile communication system, a next generation NodeB in a 6G mobile communication system, a base station in a future mobile communication system, an access node in a Wi-Fi system, etc., or may be a module or unit that performs some functions of a base station, such as a central unit (CU) or a distributed unit (DU). The CU here may perform the functions of the radio resource control protocol and packet data convergence protocol (PDCP) of the base station and may further perform the function of the service data adaptation protocol (SDAP). The DU may perform the functions of the radio link control layer and medium access control (MAC) layer of the base station and may further perform some or all of the physical layer functions. For a detailed description of the aforementioned protocol layers, reference may be made to technical specifications associated with the 3rd generation partnership project (3GPP). For example, the CU is responsible for processing non-real-time protocols and services and implementing the functions of the radio resource control (RRC) layer and the PDCP layer.The DU is responsible for processing physical layer protocols and real-time services and performs functions of the radio link control (RLC) layer, MAC layer, and physical (PHY) layer. For example, a base station may further include an active antenna unit (AAU). The AAU performs some physical layer processing functions, radio frequency processing, and functions related to the active antenna. Information at the RRC layer is ultimately converted to or from information at the PHY layer. Therefore, in this architecture, higher layer signaling, such as RRC layer signaling, may be considered to be transmitted by the DU or by the DU and AAU.

[0048] The network device may be a macro base station (e.g., 110a in FIG. 1 ), a micro base station or an indoor base station (e.g., 110b in FIG. 1 ), or may be a relay node, a donor node, etc. The specific technology used by the network device and the specific device form are not limited in the embodiments of the present application. For ease of description, the network device is used as an abbreviation for a radio access network device, and the base station is used as an example of a radio access network device.

[0049] A terminal is a device with wireless transceiver capabilities that can transmit signals to or receive signals from a base station. A terminal may also be referred to as 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) scenarios, vehicle-to-everything (V2X) communication scenarios, machine-type communication (MTC) scenarios, Internet of Things (IoT) scenarios, virtual reality scenarios, augmented reality scenarios, industrial control scenarios, autonomous driving scenarios, telemedicine scenarios, smart grid scenarios, smart furniture scenarios, smart office scenarios, smart wearable scenarios, smart transportation scenarios, and smart city scenarios. A terminal may be a mobile phone, a tablet computer, a computer with wireless transceiver capabilities, a wearable device, a vehicle, an aircraft, a ship, a robot, a robotic arm, a smart home device, etc. The specific technology and device form used by the terminal are not limited in the embodiments of the present application.

[0050] The base station and the terminal may be fixed or mobile. The base station and the terminal may be deployed on land, on water, or on an aircraft, a balloon, or a satellite, including an indoor or outdoor device, a handheld device, or an in-vehicle device. The application scenario of the base station and the terminal is not limited in the embodiments of the present application.

[0051] The roles of a base station and a terminal may be relative. For example, helicopter or unmanned aerial vehicle 120i in FIG. 1 may be configured as a mobile base station, and to terminal 120j accessing wireless access network 100 through 120i, terminal 120i is a base station. However, to base station 110a, 120i is a terminal. In other words, communication between 110a and 120i is performed based on a wireless air interface protocol. Indeed, communication between 110a and 120i may alternatively be performed based on an interface protocol between base stations. In this case, to base station 110a, 120i is also a base station. Therefore, both base stations and terminals may be collectively referred to as communication devices, and 110a and 110b in FIG. 1 may be referred to as communication devices having base station functionality, and 120a to 120j in FIG. 1 may be referred to as communication devices having terminal functionality.

[0052] Communication between base stations and terminals, between base stations and base stations, or between terminals may be performed by using licensed spectrum, or by using unlicensed spectrum, or by using both licensed and unlicensed spectrum. Communication may be performed by using spectrum below 6 gigahertz (GHz), or by using spectrum above 6 GHz, or by using both spectrum below and above 6 GHz. Spectral resources for wireless communication are not limited in the embodiments of the present application.

[0053] In the embodiments of the present application, the functions of the base station may be performed by a module (such as a chip) in the base station, or by a control subsystem including the base station functions. The control subsystem including the base station functions in this specification may be a control center in the aforementioned application scenarios, such as smart grid, industrial control, smart transportation, and smart city. The functions of the terminal may be performed by a module (such as a chip or modem) in the terminal, or by a device including the terminal functions.

[0054] FIG. 2 illustrates an application scenario applicable to an embodiment of the present application. When CA technology is applied, cell 1 may be a PCell, a terminal device communicates with the PCell via a primary carrier component (PCC), and the operating frequency of cell 1 (or the center frequency of the PCC) is F1. F1 may be a low frequency; in other words, F1 belongs to the low frequency range. An RRC connection is established between the PCell and the terminal device, and the PCell is the cell where the terminal device performs initial connection establishment, or the cell where the terminal device performs RRC connection re-establishment, or the PCell designated in the handover process. Cell 2 and cell 3 are two different SCells configured to provide additional radio resources. There is no RRC connection between the SCell and the terminal device. After the initial security activation procedure, the SCell is added / modified / released by using an RRC connection reconfiguration message. The terminal device communicates with cell 2 via secondary carrier component (SCC) 1. The frequency of cell 2 (in other words, the center frequency of SCC 1) is F2. The terminal device communicates with cell 2 via SCC 2. The frequency of cell 3 (in other words, the center frequency of SCC 2) is F3. F2 and F3 are high frequencies, in other words, F2 and F3 belong to the high frequency range.

[0055] FIG. 3 is a diagram of a beam sweeping process. A network device may transmit signals to a terminal device by using multiple transmission beams, and the terminal device may receive those signals from the network device by using multiple receive beams. A beam management process may be used to determine the beam to be used by the network device and the terminal device to perform signal reception and transmission. To determine a specific transmission beam among the multiple transmission beams to be used by the network device to transmit a signal to the terminal device, the network device may transmit a reference signal (RS) to the terminal device by traversing and using each of the multiple transmission beams. The terminal device selects a receive beam for an RS measurement report, thereby enabling the network device to determine the transmission beam to be used to transmit a signal to the terminal device. The network device then fixes the transmission beam, and the terminal device may receive the RS from the network device by traversing and using each of the multiple receive beams. Based on the RS measurement results, the terminal device may determine the receive beam to be used to receive a signal from the network device. The RS may be a TRS in this application. It may be understood that for signal reception and transmission, the receive beam and the transmit beam are typically the same beam. In other words, the transmission beam of a network device is also the reception beam through which the network device receives signals, and the reception beam of a terminal device is also the transmission beam through which the terminal device transmits signals.

[0056] The high-frequency SCell activation procedure includes cell search and Layer 1 (L1) beam measurement. The cell search includes time and frequency synchronization between the terminal device and the cell. An SSB-based SCell activation procedure is used as an example. The terminal device establishes communication with the low-frequency PCell, and the high-frequency SCell is activated as needed. When an inter-frequency cell is activated, the terminal device, in addition to performing a cell search, further needs to perform two automatic gain control (AGC) adjustments and one L1 measurement. Therefore, a total of four SSB measurements need to be performed in the entire process. In the cell search, AGC, or L1 measurement process, the network device traverses all transmission beams and transmits cell-specific SSBs, and the terminal device fixes a receiving beam for reception. Considering that the terminal device currently has receiving beams in up to eight directions, one SSB measurement includes a total of eight SSB periods. However, the period of the cell-specific SSB configured by the network device is usually long to reduce system overhead and power consumption of the network device. Currently, one SSB period is usually configured as 20 ms. In this scenario, the total inter-frequency SCell activation delay is about 4 * 8 beam sweeps * SSB period = 4 * 8 * 20 ms = 640 ms. It can be known that activation procedures such as AGC, time-frequency synchronization, and beam management in various beam directions performed based on the cell-specific SSB result in a long cell activation time, which affects user experience and increases power consumption of the terminal device.

[0057] In consideration of this, an embodiment of the present application provides a fast cell activation method, which enables a terminal device to quickly activate a cell based on service requirements, thereby improving user experience and reducing power consumption of the terminal device. The method in the embodiment of the present application is particularly applicable to activation of a high-frequency SCell. Specifically, the embodiment of the present application provides a temporary reference signal (TRS), and the TRS is applied to the cell activation procedure.

[0058] It should be noted that an SSB (in other words, a time-frequency resource occupied by an SSB) may be referred to as an SSB burst, and an SSB burst includes a PSS, an SSS, and a PBCH, and an SSB occupies four symbols in the time domain. Correspondingly, a TRS (or a time-frequency resource occupied by a TRS) may be referred to as a TRS burst.

[0059] A TRS burst may include a primary synchronization signal (PSS) and / or a secondary synchronization signal (SSS). If it includes only a PSS or SSS, the TRS burst occupies one symbol in the time domain. If it includes a PSS and SSS, the TRS burst occupies two symbols in the time domain. Alternatively, a TRS burst may include a PSS, SSS, and PBCH, occupying four symbols in the time domain.

[0060] Furthermore, SSBs (or SSB bursts) transmitted to complete one beam sweep form an SSB burst set. Correspondingly, a set of TRS bursts transmitted to complete one beam sweep is called a TRS burst set. One beam sweep can be a process of fixing the beam direction at the receiving end, traversing the beams at the transmitting end, and determining the optimal transmission beam. Alternatively, one beam sweep can be a process of fixing the beam direction at the transmitting end, traversing the beams at the receiving end, and determining the optimal reception beam. Each TRS burst in a TRS burst set can correspond to one beam direction. To complete one beam sweep, the number of TRS bursts is configured so that one TRS burst set can cover multiple beam directions.

[0061] It should be understood that the names in the embodiments of this application are merely for ease of description and understanding, and do not constitute any limitation on the scope of this application. The possibility that the above-mentioned signals and signal sets have other names in 5G networks and other future networks is not excluded in this application.

[0062] The technical solution in this application will be described in detail hereinafter with reference to the accompanying drawings. Figure 4 is a schematic flowchart of a cell activation method 400 according to an embodiment of the present application. Specifically, Figure 4 shows a process of activating a second cell through a first cell for a terminal device. A communication connection is established between the first cell and the terminal device. For example, the first cell may be a current serving cell of the terminal device, or the first cell is a cell currently accessed by the terminal device.

[0063] In some cases, this embodiment of the present application may be applied to a scenario in which a network device activates a secondary cell (i.e., an example of a second cell) via a primary cell. In this case, the first cell may be a PCell of the terminal device. Furthermore, the first cell may be a low-frequency PCell. For example, the carrier of the PCell is a FR1 carrier and the frequency range is 410 MHz to 7125 MHz. The second cell may be a high-frequency SCell. For example, the carrier of the SCell is a FR2 carrier and the frequency range is 24250 MHz to 52600 MHz. For further details regarding FR1 and FR2, please refer to Non-Patent Document 1. It should be noted that "low frequency" may be understood as a frequency range, and "high frequency" may be understood as a frequency range. For example, any frequency in the "high frequency" may be higher than any frequency in the "low frequency". As another example, "high frequencies" overlap with "low frequencies", and the frequency with the highest frequency in the "high frequencies" is higher than the frequency with the highest frequency in the "low frequencies", and the frequency with the lowest frequency in the "high frequencies" is higher than the frequency with the lowest frequency in the "low frequencies".

[0064] In another case, this embodiment of the present application may be applied to a process in which a terminal device switches from a source cell to a target cell, specifically, a process in which beam management for the target cell (i.e., another example of a second cell) is configured for the terminal device via the source cell (i.e., another example of a first cell).

[0065] It should be understood that the steps or operations shown in Figure 4 are examples only. Other operations or variations of the operations in Figure 4 may also be performed in this embodiment of the application. In addition, the steps in Figure 4 may be performed in an order different from that shown in Figure 4, and some operations in Figure 4 may not need to be performed.

[0066] As shown in FIG. 4, the method 400 may include the following steps.

[0067] S410. A network device transmits first configuration information through a first cell, and a terminal device receives the first configuration information, wherein the first configuration information indicates N time-frequency resources having a one-to-one correspondence with the N TRSs, where the N time-frequency resources are used to carry the N TRSs, respectively, and N is a positive integer.

[0068] "N time-frequency resources are each used to carry N TRSs" may be understood as the nth time-frequency resource among the N time-frequency resources being used to carry the nth TRS among the N TRSs, where n∈[1,N] and the nth time-frequency resource corresponds to the nth TRS.

[0069] The N TRSs are TRSs used to activate the second cell. In other words, the terminal device may perform beam sweeping by using some (i.e., K TRSs) or all of the N TRSs.

[0070] The terminal device may know, based on the first configuration information, N time-frequency resources respectively used to carry N TRSs.

[0071] S440. The terminal device receives K of the N TRSs on K of the N time-frequency resources, and performs beam sweeping based on the K TRSs to complete activation of the second cell, where K is a positive integer and K≦N.

[0072] "Receiving K of N TRSs on K of the N time-frequency resources" may be understood as receiving a TRS corresponding to the k-th time-frequency resource on the k-th time-frequency resource among the K time-frequency resources based on the first configuration information, where k∈[1,K].

[0073] If the second cell is a cell managed by the network device, the K TRSs are transmitted by the network device. In other words, at S440, the network device transmits K of the N TRSs on K of the N time-frequency resources.

[0074] If the second cell is a cell managed by a network device other than the network device (e.g., a target network device to which the terminal device needs to switch), the K TRSs are transmitted by the target network device.

[0075] The first configuration information is carried in RRC signaling. RRC signaling is unicast signaling transmitted by a network device to a terminal device. Therefore, the first configuration information in the RRC signaling is configuration information dedicated to the terminal device. In other words, the N TRSs indicated by the first configuration information are TRSs dedicated to the terminal device. In other words, the N time-frequency resources indicated by the first configuration information are time-frequency resources dedicated to the terminal device. That is, different terminal devices in the first cell receive the N TRSs on different time-frequency resources. Therefore, the TRSs in this application may be referred to as UE-specific TRSs or UE-dedicated TRSs.

[0076] As shown above, this embodiment of the present application provides a UE-specific TRS configuration manner, which replaces SSBs with long periods to perform the cell activation process, thereby reducing the cell activation delay.

[0077] S450. The terminal device activates the second cell based on the received K TRSs. The TRSs in this embodiment of the present application may be used in processes such as beam sweeping, cell search, AGC, and L1 measurement in the activation procedure. In implementation, after the activation of the second cell is completed, the network device and the terminal device may further perform beam management via CSI-RS.

[0078] Hereinafter, the first configuration information in this embodiment of the present application and the contents indicated by the first configuration information will be described in detail.

[0079] In this embodiment of the present application, the first configuration information indicates N TRSs and the time-frequency resources respectively used to carry the N TRSs.

[0080] The N TRSs are used to activate the second cell. For example, the N TRSs may correspond to N beams, that is, each TRS is used to sweep the corresponding beam. In addition, the angles (e.g., tilt angles and / or downtilt angles) of the N beams are different, that is, the coverage areas of the N beams are different.

[0081] In implementation, the first configuration information may include N information elements, which have a one-to-one correspondence with the N TRSs, and each information element includes information about the corresponding TRS. For example, for information element #A, if the TRS corresponding to information element #A is TRS#A, information element #A includes an identifier of TRS#A, such as a TRS resource identifier or a TRS resource index. In addition, information element #A may further include information about time-frequency resource #A used to carry TRS#A, such as time-domain location information and / or frequency-domain location information of time-frequency resource #A. In addition, information element #A includes quasi-colocation (QCL) information of TRS#A (in other words, the beam corresponding to TRS#A), such as a QCL source and a QCL type.

[0082] The first configuration information may indicate a starting time-domain position of a time-frequency resource having a first time-domain position among the N time-frequency resources. The starting time-domain position may be an absolute position, or the starting time-domain position may be a relative position with respect to a reference time point. For example, the reference time point may be a time point at which reception of the first configuration information is completed, or the reference time point may be a time point at which reception of activation information for the second cell (i.e., the first activation information) is completed. In addition, the relative position of the starting time-domain position with respect to the reference time point may include an offset of the starting time-domain position with respect to the reference time point, and the offset may be measured in slots.

[0083] As another example, there may be a time gap between two adjacent time-frequency resources in the time domain among the N time-frequency resources. In this case, the first configuration information may further indicate the time gap. Note that the gaps between any two adjacent time-frequency resources among the N time-frequency resources may be the same. In this case, the N time-frequency resources are periodically distributed. Alternatively, there may be at least two different gaps among the multiple gaps between the N time-frequency resources. This is not particularly limited in the present application.

[0084] The N TRSs may correspond to N beam directions. The terminal device may receive the TRSs by using multiple beams. The terminal device separately receives K of the N TRSs on one beam (shown as beam #1) to complete one sweep of the transmission beam. The K TRSs may be some of the N TRSs or all of the N TRSs. This is not particularly limited in this application. The process of determining the K TRSs is described in detail below. In this embodiment of the application, the multiple TRSs used by the terminal device to complete one sweep of the network device's transmission beam are called a TRS burst set.

[0085] The first configuration information may further include information related to the TRS burst set in addition to information related to the N time-frequency resources. For example, the first configuration information may further indicate an effective time of the TRS burst set. Specifically, the first configuration information may further indicate a time range from when the UE starts receiving the TRS to when the UE stops receiving the TRS. In other words, the first configuration information may further indicate a start time-domain position of a TRS having a first time-domain position among the K TRSs and an end time-domain position of a TRS having a last time-domain position among the K TRSs. The first configuration information may further indicate at least one of the number of TRSs included in the TRS burst set, a time gap between two adjacent TRS bursts in the time domain in the TRS burst set, and a transmission period of the TRS burst set.

[0086] In conclusion, in this embodiment of the present application, in some cases, the TRS burst set includes N TRS bursts, and in this case, the first configuration information includes information about time-frequency resources corresponding to the N TRS bursts.

[0087] In another case, the TRS burst set includes K of the N TRS bursts. In this case, in an implementation, the first configuration information includes information about time-frequency resources corresponding to the N TRS bursts, and the first configuration information includes associated information about the TRS burst set (or the K TRS bursts). In another implementation, the first configuration information includes information about time-frequency resources corresponding to the N TRS bursts, and indicates the associated configuration of the TRS burst set (or the K TRS bursts) by using other information or signaling (e.g., first activation information, described below).

[0088] Specifically, the first configuration information sent by the network device to the terminal device may include, but is not limited to, at least one of the following information: a start time-domain position of a TRS burst having a first time-domain position among the N TRS bursts, a start frequency-domain position of the N TRS bursts, an offset of a TRS burst having a first time-domain position among the N TRS bursts relative to a reference time instant, a quantity of TRS bursts in a TRS burst set in the time domain, a gap between two adjacent TRS bursts in the TRS burst set in the time domain, a transmission period of the TRS burst set, an effective time of the TRS burst set, a TRS resource identifier, a TRS resource index, and QCL information. The time-frequency resources used to transmit the N TRS bursts may be determined based on the information.

[0089] In a possible implementation, each of the N TRSs includes a PSS and an SSS, and the first symbol used to carry the PSS and the second symbol used to carry the SSS are in the same slot. One slot includes a total of 14 symbols. Furthermore, the first and second symbols are two consecutive symbols, and the second symbol may be placed after the first symbol or before the first symbol.

[0090] It should be noted that in this embodiment of the present application, the time-domain symbols may be orthogonal frequency division multiplexing (OFDM) symbols, discrete Fourier transform-spread-OFDM (DFT-s-OFDM) symbols, etc. Unless otherwise specified, all symbols in this embodiment of the present application are time-domain symbols.

[0091] The possible locations of the N time-frequency resources carrying the N TRS bursts may be referred to as a TRS burst pattern. Figure 5 shows an example of a TRS burst pattern. For the first TRS burst, the PSS occupies the first symbol in the slot in which the first TRS burst is located and occupies 11 resource blocks (RBs) in the frequency domain in which the first TRS burst is located, and the SSS occupies the second symbol in the slot in which the first TRS burst is located and occupies 11 RBs in the frequency domain in which the first TRS burst is located. Therefore, the time-frequency resources corresponding to the first TRS burst are two consecutive symbols in the time domain and 11 RBs in the frequency domain.

[0092] It should be noted that in this embodiment of the present application, the number of RBs occupied by the PSS and SSS forming the TRS is not limited. For example, the PSS and SSS may occupy 5 RBs, 15 RBs, or 20 RBs. Hereinafter, the TRS time-frequency resource configuration conditions will be mainly described.

[0093] For example, each TRS burst in FIG. 5 occupies two consecutive symbols in the slot and 11 RBs in the frequency domain, and there is a first time gap of two symbols between the time-frequency resources corresponding to any two adjacent TRS bursts in the time domain. Therefore, after the time-domain position corresponding to the first TRS burst is determined, the time-domain position of another TRS burst in the TRS burst set can be determined accordingly. If the first time gaps between the time-frequency resources corresponding to any two adjacent TRS bursts in the time domain are equal, the configured time-frequency resources are periodic. In the slot shown in FIG. 5 , multiple TRS bursts are carried on the 0th and 1st symbols, the 4th and 5th symbols, the 8th and 9th symbols, and the 12th and 13th symbols in the slot in which the multiple TRS bursts are located. It should be understood that the above-mentioned case in which the first time gaps between the time-frequency resources corresponding to any two adjacent TRS bursts in the time domain are equal is merely an example for description purposes and is not limiting in the present application. For N TRS bursts, there are N-1 groups of adjacent TRS bursts in the time domain, in other words, there are N-1 first time gaps. In a possible case, the N-1 first time gaps may be different from each other. In another possible case, some of the N-1 first time gaps are the same, and the remaining first time gaps are different from each other.

[0094] Symbols not occupied by a TRS in a slot may be configured for another associated signal to be used for measurements.

[0095] In a possible implementation, after transmitting a TRS burst in one beam direction, the network device needs a certain time to switch to the next beam direction and transmit the next TRS burst. Adaptation to this scenario can be implemented through the configuration of the first time gap.

[0096] Furthermore, a time gap between any two adjacent time-frequency resources in the time domain among the time-frequency resources used to carry SSBs is called a second time gap. In N SSB bursts, there are N-1 groups of adjacent SSB bursts in the time domain, i.e., N-1 second time gaps. In a possible case, the N-1 second time gaps may be the same as or different from one another. In another possible case, some of the N-1 second time gaps may be the same, and the remaining second time gaps may be different from one another.

[0097] In one possible implementation, each of the multiple first time gaps is shorter than any of the second time gaps. In another possible implementation, some of the N-1 first time gaps are longer than some of the second time gaps, and other first time gaps are shorter than other second time gaps.

[0098] Specifically, the largest time gap between any two adjacent time-frequency resources in the time domain among the N time-frequency resources is the first time gap, and the largest time gap between any two adjacent time-frequency resources in the time domain among the multiple time-frequency resources used to carry SSB is the second time gap, and the first time gap is shorter than the second time gap.

[0099] In other words, the N time-frequency resources include at least one first time-frequency resource pair, where the first time-frequency resource pair includes two adjacent time-frequency resources in the time domain, with a first time gap between the two time-frequency resources in the first time-frequency resource pair. The multiple time-frequency resources used to carry SSBs include at least one second time-frequency resource pair, where the second time-frequency resource pair includes two adjacent time-frequency resources in the time domain, with a second time gap between the two time-frequency resources in the second time-frequency resource pair. The first time gap is shorter than the second time gap. In a possible implementation, any one of the N-1 first time gaps may be shorter than any one of the multiple second time gaps. Alternatively, at least one of the N-1 first time gaps may be shorter than at least one of the multiple second time gaps.

[0100] For example, if a high frequency SCell is activated, the second time gap may be configured as 4 symbols, 8 symbols, 16 symbols, etc., and the first time gap in this embodiment of the present application may be configured as 1 symbol, 2 symbols, etc.

[0101] In addition, to improve the quality of the received signal, an optimal beam needs to be determined from multiple beams. Therefore, to complete the activation of the second cell, multiple beams in different directions need to be configured. When N time-frequency resources are configured, the value of N is less than or equal to the maximum number of beams supported by the second cell. Currently, the maximum number of beams supported by the second cell as a high-frequency cell is usually 64. In this case, the value of N is set to 64, specifically, 64 time-frequency resources can be configured to carry 64 TRS bursts, thereby satisfying the requirement of beam sweeping performed to activate the second cell. It should be understood that in this embodiment of the present application, the maximum number of beams supported by the second cell may alternatively not be equal to 64. This is not a limitation in the present application.

[0102] Generally, one TRS burst may correspond to measurements in one beam direction. Thus, in the pattern shown in FIG. 5 , four TRS bursts may be configured in one slot, and the time-frequency resources of one TRS burst set may be configured as 16 such patterns, thereby satisfying beam alignment in 64 directions of the second cell. It should be understood that TRS bursts may have a one-to-one correspondence with beam directions, or multiple TRS bursts may correspond to one beam direction, or one TRS burst may correspond to multiple beam directions. This is not a limitation in the present application.

[0103] As noted above, in this application, the time occupied by a TRS burst set is related to the symbols occupied by the TRS bursts, the gaps between the TRS bursts, and the quantity of the TRS bursts. In addition, the gaps between the TRS bursts are measured in slots. Therefore, the time occupied by a TRS burst set can be calculated in slots. For example, if the subcarrier spacing is configured as 120 kHz, the length of each slot is 0.125 ms. Therefore, in the scenario shown in FIG. 5, one TRS burst set occupies 2 ms. If the subcarrier spacing is configured as 240 kHz, each slot corresponds to 0.0625 ms. Therefore, one TRS burst set occupies 1 ms in this scenario.

[0104] It should be understood that the aforementioned TRS burst patterns are merely examples, and that a network device may configure multiple TRS burst patterns based on the system's operating frequency band, subcarrier spacing, etc.

[0105] 6 shows another example of a TRS burst pattern. In a certain slot, the first TRS burst (specifically, the TRS burst having the leading time-domain position) of six TRS bursts is configured on symbols #0 and #1 in the slot, the second TRS burst is configured on symbols #2 and #3 in the slot, the third TRS burst is configured on symbols #5 and #6 in the slot, the fourth TRS burst is configured on symbols #7 and #8 in the slot, the fifth TRS burst is configured on symbols #10 and #11 in the slot, and the sixth TRS burst (specifically, the TRS burst having the trailing time-domain position) is configured on symbols #12 and #13 in the slot. There is no first time gap between the first and second TRS bursts in the time domain. Similarly, there is no first time gap between the third and fourth TRS bursts and between the fifth and sixth TRS bursts in the time domain. There is a first time gap of one symbol between the second and third TRS bursts in the time domain. Similarly, there is a first time gap of one symbol between the fourth and fifth TRS bursts in the time domain. In this case, the first time gaps between the time-frequency resources corresponding to any two adjacent TRS bursts in the time domain are not all equal. In other words, the configured TRS time-frequency resources are aperiodic.

[0106] If the TRSs have a one-to-one correspondence with the beam directions, the time-frequency resources can be configured for one TRS burst set based on 11 such patterns to satisfy the beam sweep in 64 directions of the second cell. If two TRSs correspond to one beam direction, the time-frequency resources can be configured for one TRS burst set based on 22 such patterns to satisfy the beam sweep in 64 directions of the second cell.

[0107] In another possible implementation, for example, there may be no first time gap between the time-frequency resources corresponding to any two adjacent TRS bursts in the time domain. In this case, up to seven TRS bursts may be configured in one slot. The specific configuration manner is not described here.

[0108] It should be understood that the above-mentioned patterns are merely examples. In this embodiment of the present application, the first TRS burst may alternatively be distributed over other symbols in the slot in which the first TRS burst is located. For example, the start time-domain position corresponding to the first TRS burst may start from the second symbol or the third symbol in the slot in which the first TRS burst is located.

[0109] It should be further understood that the first time gap between the time-frequency resources carrying two adjacent TRS bursts may be set to any number of symbols, such as one symbol, two symbols, or three symbols, or the first time gap may be a time-domain unit, such as one slot or one subframe, or the first time gap is set to 0 symbols, i.e., the time-frequency resources corresponding to two adjacent TRS bursts are contiguous in the time domain.

[0110] In this embodiment of the present application, it can be known that the configuration structure and resource mapping position of the TRS burst are designed so that the time-frequency resources can be used more efficiently, thereby shortening the time for transmitting the TRS burst set in the activation process.

[0111] Currently, for activation based on a cell-specific SSB, cell search needs to be performed via both the PSS and SSS to obtain a physical cell ID (PCI) number. In contrast, in this embodiment of the present application, cell activation is performed based on a UE-specific TRS. Therefore, the PCI does not need to be obtained. In this case, symbol synchronization can be obtained via only the PSS or SSS signal. Therefore, in a possible implementation, the UE-specific TRS may include only the PSS. In another possible implementation, the UE-specific TRS may include only the SSS.

[0112] When a TRS includes only a PSS or an SSS, one TRS burst may occupy one symbol in the time domain and occupy resources of 11 RBs in the frequency domain, as shown in Figure 7. Figure 7 shows that a first time gap of one symbol is configured between the TRSs, the first TRS is located on the first symbol of the slot in which the first TRS is located, and seven TRSs are configured in one slot.

[0113] It should be understood that the starting position of a TRS, the number of occupied RBs, the first time gap on the time-frequency resource, the subcarrier spacing, etc. can be independently configured or predefined by a network device based on an actual scenario, which is not limited in this application. In a design in which one TRS occupies one symbol, system overhead and activation delay can be further reduced.

[0114] In yet another possible implementation, the TRS may further include a PBCH. Similarly, a set including the PSS, SSS, and PBCH may be referred to as a TRS burst. In this design, the PSS is carried on the first symbol, the SSS is carried on the second symbol, and the PBCH is carried on the third and fourth symbols. The first, second, third, and fourth symbols are symbols in the same slot. Furthermore, the first, second, third, and fourth symbols are consecutive in the time domain. Furthermore, the third symbol is positioned after the first symbol, and the fourth symbol is positioned after the second symbol.

[0115] 8, a TRS burst includes a PSS, an SSS, and a PBCH. The PSS in a first TRS burst is carried on the first symbol in a slot in which the first TRS burst is located, the SSS is carried on the third symbol, and the PBCH is carried on the second and fourth symbols, and the PSS, SSS, and PBCH are each configured to occupy 20 RBs in the frequency domain. It should be understood that the number of RBs occupied by the PSS, SSS, and PBCH in the frequency domain is not limited in the present application.

[0116] Furthermore, four symbols are configured for each TRS burst in the time domain, 20 RBs are configured for each TRS burst in the frequency domain, and a maximum of three TRS bursts can be configured in one slot. Additionally, if the maximum number of beam directions of the second cell is 64, one TRS burst set can be configured in 22 slots, and a maximum of 66 TRS bursts can be carried in those 22 slots to ensure optimal beam determination.

[0117] 8, when the subcarrier spacing is 120 kHz, each slot corresponds to 0.125 ms and one TRS burst set occupies a time of approximately 2.75 ms. When the subcarrier spacing is 240 kHz, each slot corresponds to 0.0625 ms and one TRS burst set occupies a time of approximately 1.375 ms.

[0118] In the above scenario, the positional relationship between the time-frequency resources carrying multiple TRS bursts can also be independently configured or predefined by the network device based on the actual scenario. For example, as shown in Figure 8, the network device may predefine that the TRS bursts having the leading time-domain positions in each slot are distributed over the 0th to 3rd symbols in the slot, and there is a first time gap of one symbol between the time-frequency resources corresponding to any two adjacent TRSs in the slot. Therefore, in the slot, the second TRS burst is carried over the 5th to 8th symbols, and the third TRS burst is carried over the 10th to 13th symbols.

[0119] It should be understood that the above-mentioned patterns are merely examples. For example, different subcarrier spacings may be configured for the TRS burst patterns, and the TRS bursts may also be carried at different positions in a slot. In addition, the time-domain positions of the TRS bursts in multiple slots may be the same or different. This is not a limitation in the present application.

[0120] It can be seen from the above that the TRS designed in the present application may include a PSS and / or an SSS, or may include a PSS, an SSS, and a PBCH. In addition, multiple time-frequency resources are configured to carry multiple TRSs in one TRS burst set to satisfy beam sweeping in multiple directions. In this embodiment of the present application, it can be seen that the configuration structure of the TRS burst and the corresponding time-frequency resources are designed so that system overhead and delays in activating a secondary cell can be reduced.

[0121] It should be understood that the TRS bursts shown in the above pattern are candidate TRS bursts configured by the network device. However, the number of TRS bursts actually transmitted and the locations of the time-frequency resources corresponding to the actually transmitted TRS bursts may be selected based on various scenarios. For example, one sweep may be completed by using 32 TRS bursts.

[0122] In a possible implementation, the terminal device may complete one beam sweep by using K of the N TRSs indicated by the first configuration information. That is, one TRS burst set includes K TRS bursts. The value of K may be less than N or equal to N. In this case, before the terminal device receives K of the N TRSs on K of the N time-frequency resources, method 400 may further include S420. Specifically, the network device may transmit first activation information to the terminal device. The terminal device receives the first activation information from the network device. The first activation information may indicate to activate a second cell. The first activation information may be carried on a MAC CE or downlink control information (DCI). For example, the MAC CE may include an identifier indicating whether to activate a cell, and each cell may correspond to one identifier. If the identifier is 1, it indicates that the cell should be activated, and if the identifier is 0, it indicates that the cell should be deactivated.

[0123] Between the time-frequency resource used to carry the TRS having the first time-domain position in the K TRSs and the time-frequency resource used to carry the first activation information, there is a third time gap Y, where Y may be configured by using signaling or may be predefined in a protocol. For example, the time-domain length corresponding to Y may be predefined in a protocol, or the network device may configure the time-domain length for the terminal device by using RRC signaling or MAC CE.

[0124] 9, the network device starts transmitting the first activation information in slot T, and after Y, the network device starts transmitting a TRS having a leading time-domain position among the K TRSs. In other words, the time-frequency resource carrying the TRS having a leading time-domain position among the K TRSs is the time-frequency resource corresponding to a point in time Y after slot T in the N time-frequency resources indicated by the first configuration information.

[0125] Correspondingly, when starting to receive the first activation information in slot T, the terminal device may calculate, based on the time when it starts to receive the first activation information and the third time gap Y, the time when it will receive the TRS having the leading time-domain position among the K TRSs, or the time-domain position of the time-frequency resource used to carry the TRS having the leading time-domain position among the K TRSs.

[0126] After a period of time (i.e., a first example duration, e.g., X slots), at slot T+X, the network device stops transmitting TRSs and the terminal device stops receiving TRSs. In other words, transmission or reception of K TRSs can be completed at or before slot T+X. In this case, the duration from the start of receiving the first activation information to the completion of receiving the TRS having the tail-end time-domain position among the K TRSs is X slots. The duration from the start of transmitting the first activation information to the completion of transmitting the TRS having the tail-end time-domain position among the K TRSs is also X slots.

[0127] X may be configured by using signaling or may be predefined in a protocol. For example, X may be configured by using RRC, or may be indicated by using MAC CE signaling, or may be indicated by feedback information sent by the terminal device to the network device. In addition, the duration corresponding to the value of X may be configured based on various scenarios of a specific terminal device. For example, X may be set to 1 ms, 2 ms, 3 ms, 5 ms, or 10 ms. This is not limited in the present application.

[0128] In the present application, the network device may perform the configuration such that the value of X can be smaller than V. The value of V corresponds to the time from the start of receiving the second activation information by the terminal device to the completion of receiving an SSB having a tail-end time-domain position in N SSBs (i.e., an example of a second duration, e.g., V slots). The second activation information is the activation information received when the second cell is activated via the N SSBs. In other words, the value of V corresponds to the time from the start of transmitting the second activation information to the completion of transmitting an SSB having a tail-end time-domain position in K SSBs, and the second activation information is the activation information transmitted when the second cell is activated via the N SSBs.

[0129] It should be understood that the above-mentioned activation process (in other words, TRS transmission process) of the second cell triggered by using the first activation information is merely an example for description. The present application is not limited thereto. When the terminal device receives the first configuration information and knows the time-frequency resources corresponding to the N TRSs, the TRS reception process can be triggered based on actual requirements (e.g., user indication or condition triggering), etc.

[0130] In this embodiment of the present application, the K TRSs may be all of the N TRSs, or the K TRSs may be some of the N TRSs.

[0131] In a possible implementation, K TRSs may be transmitted periodically from slot T to slot T+X. Specifically, the first time gaps between any two adjacent time-frequency resources in the time domain used to carry the TRSs are equal. In another possible implementation, TRSs may alternatively be transmitted aperiodically from slot T to slot T+X. Specifically, the first time gaps between any two adjacent time-frequency resources in the time domain used to carry the TRSs are not all equal.

[0132] The following describes in detail how the terminal device determines the K TRSs when the K TRSs can be some of the N TRSs.

[0133] In a possible implementation, the method 400 may further include step S430. Specifically, the network device transmits first indication information to the terminal device, where the first indication information indicates K of the N TRSs. The transmission of the TRSs may be indicated by using corresponding identifiers TRS IDs. In a possible implementation, the first indication information may be MAC CE signaling, RRC signaling, or physical layer signaling.

[0134] Specifically, the first indication information may include an identifier #A, which may indicate identifiers of K TRSs among the N TRSs that need to be received by the terminal device. Because the first configuration information indicates a one-to-one mapping relationship between the identifiers of the N TRSs and the N time-frequency resources, the terminal device can determine the time-frequency resource corresponding to the identifier #A based on the first configuration information, thereby transmitting the K TRSs on the time-frequency resource. By way of example and not limitation, the identifier #A may be implemented in the form of a bitmap. For example, the identifier #A may include N bits, which have a one-to-one correspondence with the N TRSs indicated by the first configuration information, and the value of each bit indicates whether the terminal device needs to receive the TRS corresponding to that bit. This may also be understood as the bitmap indicating K TRSs among the N TRSs.

[0135] For example, in a case where the network device provides multiple high-frequency secondary cells, in a possible implementation, the first indication information may further include an identifier #B, which indicates the second cell. Therefore, the terminal device can determine the K TRSs to use when activating the second cell based on the identifier #B. By way of example and not limitation, the identifier #B may be implemented in the form of a bitmap. For example, the identifier #B may include multiple bits, which have a one-to-one correspondence with multiple cells, and the value of each bit indicates whether the cell corresponding to that bit needs to be activated.

[0136] In another possible implementation, the first indication information may further include an identifier #C, which indicates a specific value of K. In other words, the terminal device can determine the number of TRSs that need to be received in the N TRSs based on the identifier #C. Note that the specific value of K may be indirectly determined by using the identifier #A. In this case, the first indication information may not need to carry the identifier #C.

[0137] In a possible implementation, the first indication information and the first activation information are carried in the same signaling. As shown in Figure 10, the first indication information and the first activation information are carried in the same MAC CE signaling. In this case, step S420 and step S430 are combined into one step. In this case, the MAC CE signaling may indicate to the terminal device to activate the second cell and indicate the transmission of K TRSs in the cell.

[0138] The network device transmits a MAC CE in slot T and transmits K TRSs after a third time gap. In addition, the terminal device receives first activation information and starts receiving TRSs after a third time gap (e.g., Y slots). The length of the time domain corresponding to the third time gap may be predefined in a protocol, configured by using RRC, or indicated by the first indication information. In the third time gap, the terminal device may prepare to receive TRSs, thereby improving the reliability and accuracy of the communication technology provided in the present application.

[0139] As shown in FIG. 11 , in a possible implementation, K TRSs, specifically, TRS#1, TRS#2, ..., and TRS#K, are used to complete one beam sweep, and TRS#1, TRS#2, ..., and TRS#K form a TRS burst set. The K TRSs belong to one of multiple TRS burst sets. For example, a terminal device has eight receive beams. For each receive beam, the terminal device needs to perform one beam sweep for the network device's transmission beam; in other words, it needs to receive the K TRSs in one TRS burst set and determine the optimal transmission beam when that receive beam is used to receive the TRS. To further determine the terminal device's optimal receive beam, the terminal device needs to sequentially use the eight receive beams to sweep the network device's transmission beam; in other words, it needs to receive a total of 8*K TRSs in eight TRS burst sets. These eight TRS burst sets are sequentially TRS burst set #1 to TRS burst set #8.

[0140] As shown in Figure 11, there is a fourth time gap between two adjacent TRS burst sets in the time domain. For example, there is a fourth time gap between TRS burst set #1 and TRS burst set #2. In contrast, as shown in Figure 12, a fifth time gap is a time gap between two adjacent SSB burst sets in the time domain in a plurality of SSB burst sets. For example, there is a fifth time gap between SSB burst set #1 and SSB burst set #2. The fourth time gap is shorter than the fifth time gap in this embodiment of the present application because a dedicated time-frequency resource is configured in this application for terminal devices to transmit TRSs, thereby allowing for a relatively short fourth time gap.

[0141] In this embodiment of the present application, the length of the time gap between the start time-domain positions of two adjacent TRS burst sets in the time domain is called the TRS period. Currently, all SSBs in one SSB burst set must be transmitted in the same half-frame (5 ms). In other words, a network device must complete a sweep of the entire cell within 5 ms. However, the SSB period is generally not equal to 5 ms. During an initial cell search, a terminal device searches for SSBs based on a default period of 20 ms. In this embodiment of the present application, the configured TRS period is shorter than the SSB period, thereby reducing the time required for multiple beam sweeps and further reducing the activation delay.

[0142] The TRS period is typically configured in units called time domain units. The time domain unit may be milliseconds (ms), slots, minislots, frames, subframes, etc. For example, the TRS period may be configured as 10 slots, 16 slots, one subframe, etc. Based on different subcarrier spacings, one slot corresponds to different periods of time, whereby the TRS period may be configured as 1 ms, 2 ms, 3 ms, 4 ms, 5 ms, 10 ms, 15 ms, etc. This is not a limitation in the present application.

[0143] It can be known in the present application that a short TRS period can be configured for a specific terminal device to reduce the time the terminal device waits to receive a TRS in the activation process, which helps to reduce delays in the activation procedure and improve the user experience.

[0144] In a possible implementation, the TRS period in this application may be configured as 2 ms. In the activation process, the terminal device needs to perform one cell search, two AGCs, and one L1 measurement. Therefore, a total of four TRS measurements need to be performed in the entire process. Considering that the terminal device has up to eight beams and that all TRS beams of the network device need to be measured for each beam, one TRS measurement includes a total of eight TRS periods. Therefore, the entire activation procedure includes 32 TRS periods, and the total delay is approximately 64 ms. It can be seen that using a UE-specific TRS can perform more efficient cell search and beam sweeping compared to conventional technologies.

[0145] In a possible implementation, in the process of the terminal device performing AGC or time-frequency synchronization by using the TRS, the terminal device may simultaneously obtain L1 reference signal received power (RSRP) information by using the TRS, thereby avoiding the procedure of separately performing one L1-RSRP measurement, and further reducing the delay overhead in the activation procedure.

[0146] By way of example and not limitation, in the present application, after a UE-specific TRS is introduced for SCell activation, a specific SCell activation delay T satisfies the following formula: T=W+TTRS_MAX+n·TTRS_MAX+TL1-RSRP, measure+TL1-RSRP, report+max{(THARQ+Tuncertainty_MAC+Z+TFineTiming), (Tuncertainty_RRC+TRRC_delay)}

[0147] where W represents the time for processing activation information (e.g., MAC CE) by a terminal device. For example, the value of W may be 3 milliseconds (ms), TTRS_MAX represents the TRS period, n is the number of TRS periods in the SCell activation process, and Z is a pre-configured constant. For example, the value of Z may be 5 ms. TL1-RSRP, measure is the L1-RSRP measurement delay. For descriptions of the TL1-RSRP, report, TFineTiming, and TRRC_delay parameters, please refer to the related descriptions in Section 8.3.2 of 3GPP TS 36.210.

[0148] Since the TRS period in this application is significantly shorter than the SSB period specified in Non-Patent Document 2, the delay in the high-frequency SCell activation procedure can be effectively reduced.

[0149] It can be noted that this embodiment of the present application provides a UE-specific TRS configuration manner. By transmitting the TRS periodically or aperiodically, SSBs with long periods can be replaced, thereby reducing cell activation delays.

[0150] In a possible implementation, in this embodiment of the present application, L1-RSRP information may further be obtained by using the TRS. Furthermore, the L1-RSRP information may be obtained based on the TRS in the process of performing AGC and / or time-frequency synchronization, thereby avoiding the process of separately performing L1-RSRP measurement and further reducing the delay in the high-frequency SCell activation procedure.

[0151] As described above, the K TRSs used to activate the second cell (or the K TRSs that need to be received by the terminal device) may be some of the N TRSs. The following describes in detail a specific process by which the network device determines the K TRSs.

[0152] For example, in a high-frequency SCell activation procedure, known low-frequency cell information may be used to assist in predicting the transmit and / or receive beams of the high-frequency cell, thereby reducing delays in the cell activation procedure. Note that this prediction method may also be used in scenarios where beam sweeping is performed via SSB or another signal. This is not a limitation in this application.

[0153] Specifically, the beam set used by the second cell typically includes multiple beams (e.g., N beams). The network device may predict the N beams and determine a beam set (denoted as beam set #a) from which the optimal beam may occur. Beam set #a is a subset of the beam set including N beams. For example, beam set #a includes beams corresponding to K TRSs.

[0154] In the present application, the above prediction can be carried out in the following manners 1 and 2.

[0155] Form 1

[0156] High-frequency and low-frequency channels are correlated in terms of subpath-level characteristics, and therefore, in a possible implementation, the transmitting device may perform such prediction by extracting the subpath characteristics of the low-frequency cell.

[0157] A specific prediction process is to perform inference based on the quasi-colocation (QCL) relationship between the signal of a known cell and the signal of a cell to be activated (i.e., the second cell). If the channel characteristics acting on an antenna port can be inferred from another antenna port, the two ports are considered to be QCLed.

[0158] The QCL relationship between signals can be configured by using RRC signaling. The QCL relationship can include four types: QCL-TypeA, QCL-TypeB, QCL-TypeC, and QCL-TypeD. The features and functions of each type are shown in Table 1.

[0159] [Table 1]

[0160] A signal having a QCL relationship with a TRS may include, but is not limited to, an SSB or another RS.

[0161] Form 2

[0162] The network device may predict beam set #a in advance by using historical information of the high-frequency cell (i.e., an example of the second cell). For example, when a terminal device accesses the second cell, the network device may add a beam determined by the terminal device in the historical record through beam sweeping to beam set #a. As another example, when a terminal device near the terminal device accesses the second cell, the network device may add a beam determined by the terminal device near the terminal device through beam sweeping to beam set #a.

[0163] After prediction, the number of beams in the transmission beam set can be reduced from N to K in the predicted transmission beam set. As described above, in this embodiment of the present application, there is a correspondence between multiple beams used by the network device (or the second cell) and multiple TRSs. Therefore, the TRSs corresponding to the K beams can be determined as the K TRSs that need to be received by the terminal device.

[0164] It should be understood that the above prediction process may occur before the network device configures N TRS time-frequency resources for the terminal device. In this case, the K TRS time-frequency resources may be directly configured based on the prediction result to carry the K TRSs. Alternatively, the above prediction process may occur after the network device configures N TRS time-frequency resources for the terminal device. In this case, the corresponding K TRSs may be transmitted on K of the N time-frequency resources based on the prediction result to complete beam sweeping on the predicted candidate beams.

[0165] It is assumed that the transmission beam set corresponding to the second cell has a total of 16 beams, numbered as beam ID=0, beam ID=1, beam ID=2, ..., and beam ID=15, respectively. For example, the beams in the transmission beam set obtained through the above-mentioned prediction are beam ID=3, beam ID=6, and beam ID=10. In this case, the network device may transmit TRS in those three directions, and the terminal device may traverse and measure the beams in those three directions to complete the activation process. The number of UE-specific TRS bursts to be transmitted may be determined based on the transmission beam set obtained through prediction. In this case, the terminal device needs to configure only three UE-specific TRS bursts to complete one TRS beam sweep. After prediction, the number of UE-specific TRS bursts to be configured and resource information for configuring the UE-specific TRS may be delivered to the terminal device by using RRC signaling or MAC CE signaling.

[0166] It can be understood that to implement the functions in the foregoing embodiments of the present application, the network device and the terminal device include corresponding hardware structures and / or software modules for performing these functions. In this application, those skilled in the art should easily realize that the units and method steps in the examples described in connection with the embodiments disclosed in the present application can be implemented by hardware or a combination of hardware and computer software. Whether the functions are performed by hardware or by hardware driven by computer software depends on the specific application scenario and design constraints of the technical solution.

[0167] 13 and 14 are diagrams of possible communication device structures according to embodiments of the present application. These communication devices may be configured to implement the functions of the terminal device or network device in the above-described method embodiments, and thus may also implement the beneficial effects in the above-described method embodiments. In this embodiment of the present application, the communication device may be one of the terminal devices 120a to 120j shown in FIG. 1, or may be the network device 110a or 110b shown in FIG. 1, or may be a module (e.g., a chip) used in the terminal device or network device.

[0168] 13, the communication device 1300 includes a processing unit 1310 and a transceiver unit 1320. The communication device 1300 is configured to perform the functions of the terminal device or the network device in the method embodiment shown in FIG.

[0169] 4, the transceiver unit 1320 is configured to receive first configuration information from the network device via the first cell, the first configuration information indicating N time-frequency resources in a one-to-one correspondence with N temporary reference signals (TRSs), each of which is used to carry the N TRSs. The transceiver unit 1320 is further configured to receive K of the N TRSs on K of the N time-frequency resources, where K and N are positive integers and K≦N. The processing unit 1310 is configured to activate the second cell based on the K TRSs.

[0170] In some implementations, the transceiver unit 1320 is further configured to receive first indication information from the network device, where the first indication information indicates K of the N TRSs. In other words, the first indication information may indicate K triggered TRSs among the N configured TRSs.

[0171] 4, the transceiver unit 1320 is configured to transmit first configuration information to a terminal device via a first cell, the first configuration information indicating N time-frequency resources in a one-to-one correspondence with N temporary reference signals TRSs, each of the N time-frequency resources being used to carry the N TRSs. The transceiver unit 1320 is further configured to transmit K of the N TRSs on K of the N time-frequency resources, where K and N are positive integers and K≦N. The processing unit 1310 is configured to generate the first configuration information and the TRSs.

[0172] In a possible implementation, the transceiver unit 1320 is further configured to transmit first activation information to the terminal device, where the first activation information may indicate to activate the second cell.

[0173] In a possible implementation, the transceiver unit 1320 is further configured to transmit first indication information to a terminal device, where the first indication information indicates K of the N TRSs.

[0174] It should be understood that the specific processes by which those units perform the above-mentioned corresponding steps have been described in detail in the above-mentioned method embodiments, and for the sake of brevity, the details will not be described here.

[0175] 14, the communication device 1400 includes a processor 1410 and an interface circuit 1420. The processor 1410 and the interface circuit 1420 are coupled to each other. It can be understood that the interface circuit 1420 may be a transceiver or an input / output interface. Optionally, the communication device 1400 may further include a memory 1430 configured to store instructions to be executed by the processor 1410, to store input data required for the processor 1410 to execute the instructions, or to store data generated after the processor 1410 executes the instructions.

[0176] When the communications device 1400 is configured to perform the method shown in FIG. 4, the processor 1410 is configured to perform the functions of the processing unit 1310, and the interface circuit 1420 is configured to perform the functions of the transceiver unit 1320.

[0177] If the communication device is a chip used in a terminal device, the chip in the terminal device performs the functions of the terminal device in the above-mentioned method embodiments. The chip in the terminal device receives information from another module (e.g., a radio frequency module or an antenna) in the terminal device, and the information is transmitted to the terminal device by the network device. Alternatively, the chip in the terminal device transmits information to another module (e.g., a radio frequency module or an antenna) in the terminal device, and the information is transmitted to the network device by the terminal device.

[0178] If the communication apparatus is a module used in a network device, the module in the network device performs the functions of the network device in the above-described method embodiments. The module in the network device receives information from another module (e.g., a radio frequency module or an antenna) in the network device, and the information is transmitted to the network device by a terminal device. Alternatively, the module in the network device transmits information to another module (e.g., a radio frequency module or an antenna) in the network device, and the information is transmitted to the terminal device by the network device. The network device module in this specification may be a baseband chip of the network device, or may be a DU or another module. The DU in this specification may be a DU in an open radio access network (O-RAN) architecture.

[0179] It may be understood that the processor in the embodiments of the present application may be a central processing unit (CPU), or may be another general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), or another programmable logic device, a transistor logic device, a hardware component, or any combination thereof. The general-purpose processor may be a microprocessor or any conventional processor.

[0180] The method steps in the embodiments of the present application may be implemented in hardware or software instructions that can be executed by a processor. The software instructions may include corresponding software modules. The software modules may 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 disk drives, removable hard disk drives, read-only memory (ROM), or any other form of storage medium well known in the art. For example, a storage medium may be coupled to the processor, thereby enabling the processor to read information from and write information to the storage medium. The storage medium may alternatively be components of the processor. The processor and the storage medium may be located in an ASIC. In addition, the ASIC may be located in a network device or a terminal device. Alternatively, the processor and the storage medium may exist as separate components in the network device or the terminal device.

[0181] All or some of the above-described embodiments may be implemented using software, hardware, firmware, or any combination thereof. When software is used to implement the embodiments, all or some of the embodiments may be implemented in the form of a computer program product. The computer program product includes one or more computer programs or instructions. When the computer programs or instructions are loaded and executed on a computer, all or some of the procedures or functions in the embodiments of the present application are performed. The computer may be a general-purpose computer, a special-purpose computer, a computer network device, a network device, user equipment, or another programmable device. The computer program or instructions may be stored on a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer program or instructions may be transmitted from a website, computer, server, or data center to another website, computer, server, or data center in a wired or wireless manner. The computer-readable storage medium may be any available medium that can be accessed by a computer or a data storage device, such as a server or data center, incorporating one or more available media. The available media may be magnetic media, such as floppy disks, hard disk drives, or magnetic tape, or optical media, such as digital video disks, or semiconductor media, such as solid-state drives. The computer-readable storage medium may be volatile or non-volatile, or may include both volatile and non-volatile storage media.

[0182] In the embodiments of the present application, unless otherwise specified or there is no logical contradiction, the terms and / or descriptions in different embodiments are consistent and can be cross-referenced, and the technical features in different embodiments can be combined based on their internal logical relationships to form a new embodiment.

[0183] It should be understood that in this application, "at least one" means one or more, "multiple" means two or more, and the term "and / or" describes an association relationship between associated objects and indicates that three relationships may exist. For example, "A and / or B" may represent the cases where "only A is present," "both A and B are present," and "only B is present," and A and B may be singular or plural. In the written description of this application, the character " / " generally represents an "or" relationship between associated objects.

[0184] It should be understood that various numbers in the embodiments of the present application are only used for distinction to facilitate description, and are not used to limit the scope of the embodiments of the present application. The sequence numbers of the above processes do not mean the execution sequence, and the execution sequence of these processes should be determined based on the functions and internal logic of these processes.

[0185] The above description is merely a specific implementation of the present application and is not intended to limit the scope of protection of the present application. Any modifications or replacements that can be easily conceived by those skilled in the art within the technical scope disclosed in the present application shall fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be subject to the scope of protection of the claims.

Claims

1. A cell activation method executed by a terminal device or a module used in a terminal device, comprising: receiving first configuration information from a network device via a first cell, the first configuration information indicating N time-frequency resources in a one-to-one correspondence with N temporary reference signals TRSs, each of the N time-frequency resources being used to carry one of the N TRSs; receiving K of the N TRSs on K of the N time-frequency resources, where K and N are positive integers and K≦N; activating a second cell based on the K TRSs; A cell activation method comprising:

2. The method of claim 1 , wherein the first configuration information is carried in radio resource control (RRC) signaling.

3. The method comprises:

3. The method of claim 1, further comprising receiving first indication information from the network device, the first indication information indicating the K of the N TRSs.

4. The method according to claim 1 , wherein the first cell is a primary cell of the terminal device and the second cell is a secondary cell of the terminal device.

5. 5. The method according to claim 1, wherein a first time gap is a maximum time gap between any two adjacent time-frequency resources in the time domain among the N time-frequency resources, and a second time gap is a maximum time gap between any two adjacent time-frequency resources in the time domain among a plurality of time-frequency resources used to carry a synchronization signal and a physical broadcast channel block (SSB), and the first time gap is shorter than the second time gap.

6. 6. The method of claim 1, wherein each of the N TRSs includes a primary synchronization signal (PSS) and a secondary synchronization signal (SSS), and a first symbol used to carry the PSS and a second symbol used to carry the SSS are in the same slot.

7. 7. The method of claim 1, wherein there is a third time gap between time-frequency resources used to carry first activation information and time-frequency resources used to carry a TRS having a first time-domain position in the K TRSs, the first activation information indicating to activate the second cell, and the third time gap is configured by using signaling or is predefined in a protocol.

8. 8. The method of claim 1, wherein a first duration is shorter than a second duration, the first duration being a duration from a start of receiving the first activation information to a completion of receiving a TRS having a time-domain position at the tail end of the K TRSs, and the second duration being a duration from a start of receiving second activation information to a completion of receiving an SSB having a time-domain position at the tail end of the N SSBs, the N SSBs being used to activate the second cell, and the first activation information and the second activation information indicating to activate the second cell.

9. 9. The method of claim 1, wherein the K TRSs belong to one of a plurality of TRS burst sets, and there is a fourth time gap between two adjacent TRS burst sets in the time domain, the fourth time gap being shorter than a fifth time gap, and the fifth time gap being the time gap between two adjacent SSB burst sets in the time domain in the plurality of SSB burst sets.

10. 1. A cell activation method performed by a network device or a module used in a network device, comprising: transmitting first configuration information via a first cell, the first configuration information indicating N time-frequency resources in a one-to-one correspondence with N temporary reference signals TRSs, each of the N time-frequency resources being used to carry one of the N TRSs; transmitting K of the N TRSs on K of the N time-frequency resources, wherein the K TRSs are used to activate a second cell, K and N are positive integers, and K≦N; A cell activation method comprising:

11. The method of claim 10 , wherein the first configuration information is carried in radio resource control (RRC) signaling.

12. The method comprises: The method of claim 10 or 11, further comprising: transmitting first indication information, wherein the first indication information indicates the K of the N TRSs.

13. The method according to claim 10 , wherein the first cell is a primary cell of a terminal device and the second cell is a secondary cell of the terminal device.

14. 14. The method according to claim 10, wherein a first time gap is a maximum time gap between any two adjacent time-frequency resources in the time domain among the N time-frequency resources, and a second time gap is a maximum time gap between any two adjacent time-frequency resources in the time domain among a plurality of time-frequency resources used to carry a synchronization signal and a physical broadcast channel block (SSB), and the first time gap is shorter than the second time gap.

15. 15. The method of claim 10, wherein each of the N TRSs includes a primary synchronization signal (PSS) and a secondary synchronization signal (SSS), and a first symbol used to carry the PSS and a second symbol used to carry the SSS are in the same slot.

16. 16. The method of claim 10, wherein there is a third time gap between time-frequency resources used to carry first activation information and time-frequency resources used to carry a TRS having a first time-domain position in the K TRSs, the first activation information indicating to activate the second cell, and the third time gap is configured by using signaling or is predefined in a protocol.

17. 17. The method of claim 10, wherein a first duration is shorter than a second duration, the first duration being a duration from a start of receiving the first activation information to a completion of receiving a TRS having a time-domain position at the tail end of the K TRSs, and the second duration being a duration from a start of receiving second activation information to a completion of receiving an SSB having a time-domain position at the tail end of the N SSBs, the N SSBs being used to activate the second cell, and the first activation information and the second activation information indicating to activate the second cell.

18. 18. The method of claim 10, wherein the K TRSs belong to one of a plurality of TRS burst sets, and there is a fourth time gap between two adjacent TRS burst sets in the time domain, the fourth time gap being shorter than a fifth time gap, and the fifth time gap being the time gap between two adjacent SSB burst sets in the time domain in the plurality of SSB burst sets.

19. 19. A communications device comprising a processor and an interface circuit, the interface circuit being configured to receive signals from another communications device and transmit the signals to the processor or to transmit signals from the processor to another communications device, the processor being configured to implement the method of any one of claims 1 to 9 or any one of claims 10 to 18 by using logic circuits or by executing code instructions.

20. 19. A computer-readable storage medium having stored thereon a computer program or instructions which, when executed by a communication device, cause the method of any one of claims 1 to 9 to be performed or cause the method of any one of claims 10 to 18 to be performed.

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