Cell configuration handover in wireless communications

Abstract

The invention relates to cell configuration handover in wireless communications. According to an embodiment of the present disclosure, a method performed by a user equipment (UE) in a wireless communication system includes: receiving a list of cell configurations for a plurality of candidate cells from a network via a source cell; performing mobility from the source cell to a first target cell among the plurality of candidate cells based on applying the cell configuration for the first target cell; determining whether to update a list by storing a cell configuration for a source cell in the list based on first control information received from a network after performing mobility to a first target cell; and performing a measurement for subsequent mobility based on the updated list.

Description

Technical Field

[0001] The present disclosure relates to cell configuration switching in wireless communication. Background Art

[0002] The 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) is a technology that allows high-speed packet communication. Many solutions have been proposed for LTE goals, including those aimed at reducing user and vendor costs, improving service quality, and extending and improving coverage and system capacity. As an upper layer requirement, 3GPP LTE needs to reduce cost per bit, increase service availability, flexibly use frequency bands, have a simple structure, open interfaces, and appropriate power consumption of terminals.

[0003] The International Telecommunication Union (ITU) and 3GPP have started to develop requirements and specifications for a New Radio (NR) system. 3GPP must identify and develop the technical components required for the successful standardization of a new Radio Access Technology (RAT) that will meet both the urgent market needs in a timely manner and the longer-term requirements proposed by the ITU Radiocommunication Sector (ITU-R) International Mobile Telecommunications (IMT)-2020 process. In addition, NR should be able to use any spectrum band in at least the up to 100 GHz range that will be available for wireless communication even in the more distant future.

[0004] The goal of NR is to be a single technical framework for all usage scenarios, requirements, and deployment scenarios, including enhanced mobile broadband (eMBB), massive machine type communication (mMTC), ultra-reliable and low-latency communication (URLLC), etc. NR should be inherently forward compatible.

[0005] In wireless communication, a User Equipment (UE) can perform mobility from a source cell to a target cell. For this mobility, the UE can be configured with one or more cell configurations and can perform the mobility to the target cell based on applying the cell configuration for the target cell. After the mobility, the serving cell configuration can be switched to a candidate cell configuration. However, in some cases, this may result in an inappropriate fallback to the serving cell configuration. Summary of the Invention

[0006] Solution to the Problem

[0007] One aspect of the present disclosure is to provide a method and an apparatus for cell configuration switching in a wireless communication system.

[0008] According to an embodiment of the present disclosure, a method performed by a user equipment (UE) in a wireless communication system includes: receiving, via a source cell, a list of cell configurations for a plurality of candidate cells from a network; performing mobility from the source cell to a first target cell among the plurality of candidate cells based on applying the cell configuration for the first target cell; after performing the mobility to the first target cell, determining, based on first control information received from the network, whether to update the list by storing the cell configuration for the source cell in the list; and performing measurements for subsequent mobility based on the updated list.

[0009] According to an embodiment of the present disclosure, a user equipment (UE) configured to operate in a wireless communication system includes: at least one transceiver; at least one processor; and at least one memory operatively coupled to the at least one processor and storing instructions that, when executed by the at least one processor, perform operations including: receiving, via a source cell, a list of cell configurations for a plurality of candidate cells from a network; performing mobility from the source cell to a first target cell among the plurality of candidate cells based on applying the cell configuration for the first target cell; after performing the mobility to the first target cell, determining, based on first control information received from the network, whether to update the list by storing the cell configuration for the source cell in the list; and performing measurements for subsequent mobility based on the updated list.

[0010] According to an embodiment of the present disclosure, a network node configured to operate in a wireless communication system includes: at least one transceiver; at least one processor; and at least one memory operatively coupled to the at least one processor and storing instructions that, when executed by the at least one processor, perform operations including: sending to a user equipment (UE) a list of cell configurations for a plurality of candidate cells; and sending to the UE a reference signal related to the plurality of candidate cells for mobility to a target cell among the plurality of candidate cells, wherein the UE is configured to: perform mobility from the source cell to the target cell based on applying the cell configuration for the target cell; after performing the mobility to the target cell, determining, based on control information received from the network, whether to update the list by storing the cell configuration for the source cell in the list; and performing measurements for subsequent mobility based on the updated list.

[0011] According to an embodiment of the present disclosure, a method performed by a network node configured to operate in a wireless communication system includes: sending a cell configuration list for a plurality of candidate cells to a user equipment (UE); and sending a reference signal related to the plurality of candidate cells for mobility to a target cell among the plurality of candidate cells, wherein the UE is configured to: perform mobility from a source cell to the target cell based on applying the cell configuration for the target cell; after performing the mobility to the target cell, determine whether to update the list by storing the cell configuration for the source cell in the list based on control information received from the network; and perform measurements for subsequent mobility based on the updated list.

[0012] According to an embodiment of the present disclosure, an apparatus adapted to operate in a wireless communication system includes: at least one processor; and at least one memory operatively coupled to the at least one processor and storing instructions that, when executed by the at least one processor, perform operations including: receiving, via a source cell, a list of cell configurations for a plurality of candidate cells from a network; performing mobility from the source cell to a first target cell among the plurality of candidate cells based on applying the cell configuration for the first target cell; after performing the mobility to the first target cell, determining whether to update the list by storing the cell configuration for the source cell in the list based on first control information received from the network; and performing measurements for subsequent mobility based on the updated list.

[0013] According to an embodiment of the present disclosure, a non-transitory computer-readable medium (CRM) stores program code that implements instructions that, when executed by at least one processor, perform operations including: receiving, via a source cell, a list of cell configurations for a plurality of candidate cells from a network; performing mobility from the source cell to a first target cell among the plurality of candidate cells based on applying the cell configuration for the first target cell; after performing the mobility to the first target cell, determining whether to update the list by storing the cell configuration for the source cell in the list based on first control information received from the network; and performing measurements for subsequent mobility based on the updated list.

[0014] The present disclosure can have various beneficial effects.

[0015] For example, the UE can selectively switch the serving cell configuration to a candidate cell configuration after mobility, thereby preventing an inappropriate fallback to the serving cell configuration after mobility.

[0016] The beneficial effects that can be obtained through the specific embodiments of the present disclosure are not limited to the beneficial effects listed above. For example, there may be various technical effects that can be understood and / or derived from the present disclosure by those of ordinary skill in the relevant art. Therefore, the specific effects of the present disclosure are not limited to those explicitly described herein, but may include various effects that can be understood or derived from the technical features of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 FIG. shows an example of a communication system to which an implementation of the present disclosure is applied.

[0018] Figure 2 FIG. shows an example of a wireless device to which an implementation of the present disclosure is applied.

[0019] Figure 3 FIG. shows an example of a UE to which an implementation of the present disclosure is applied.

[0020] Figure 4 and Figure 5 FIG. shows an example of a protocol stack in a 3GPP-based wireless communication system to which an implementation of the present disclosure is applied.

[0021] Figure 6 FIG. shows a frame structure in a 3GPP-based wireless communication system to which an implementation of the present disclosure is applied.

[0022] Figure 7 FIG. shows an example of a data flow in a 3GPP NR system to which an implementation of the present disclosure is applied.

[0023] Figure 8 FIG. shows an example of a conventional handover process to which the technical features of the present disclosure can be applied.

[0024] Figure 9 FIG. shows an example of a conditional handover process to which the technical features of the present disclosure can be applied.

[0025] Figure 10 FIG. shows an example of configuration parameters of a cell according to an embodiment of the present disclosure.

[0026] Figure 11 FIG. shows an example of configuration parameters of a cell before a serving cell change according to an embodiment of the present disclosure.

[0027] Figure 12 FIG. shows an example of configuration parameters of a cell after a serving cell change according to an embodiment of the present disclosure.

[0028] Figure 13 FIG. shows an example of a method performed by a UE according to an embodiment of the present disclosure.

[0029] Figure 14Shows an example of the signal flow between a UE and a network node according to an embodiment of the present disclosure.

[0030] Figure 15 Shows an example of a method for configuring a source cell for post-mobility processing according to an embodiment of the present disclosure. Detailed implementation

[0031] The following technologies, devices, and systems can be applied to various wireless multi-access systems. Examples of multi-access systems include code division multiple access (CDMA) systems, frequency division multiple access (FDMA) systems, time division multiple access (TDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, single-carrier frequency division multiple access (SC-FDMA) systems, and multi-carrier frequency division multiple access (MC-FDMA) systems. CDMA can be implemented through radio technologies such as Universal Terrestrial Radio Access (UTRA) or CDMA2000. TDMA can be implemented through radio technologies such as Global System for Mobile Communications (GSM), General Packet Radio Service (GPRS), or Enhanced Data Rates for GSM Evolution (EDGE). OFDMA can be implemented through radio technologies such as Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, or Evolved UTRA (E-UTRA). UTRA is part of the Universal Mobile Telecommunications System (UMTS). The 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) is part of the Evolved UMTS (E-UMTS) using E-UTRA. 3GPP LTE employs OFDMA in the downlink (DL) and SC-FDMA in the uplink (UL). The evolution of 3GPP LTE includes LTE-Advanced (LTE-A), LTE-A Pro, and / or 5G New Radio (NR).

[0032] For ease of description, the implementation of the present disclosure is mainly described with respect to 3GPP-based wireless communication systems. However, the technical features of the present disclosure are not limited thereto. For example, although the following detailed description is given based on a mobile communication system corresponding to a 3GPP-based wireless communication system, aspects of the present disclosure that are not limited to 3GPP-based wireless communication systems are applicable to other mobile communication systems.

[0033] For terms and technologies not specifically described among the terms and technologies adopted in the present disclosure, reference can be made to wireless communication standard documents published prior to the present disclosure.

[0034] In the present disclosure, "A or B" may mean "only A", "only B", or "both A and B". In other words, in the present disclosure, "A or B" may be interpreted as "A and / or B". For example, in the present disclosure, "A, B, or C" may mean "only A", "only B", "only C", or "any combination of A, B, and C".

[0035] In the present disclosure, a slash ( / ) or a comma (,) may mean "and / or". For example, "A / B" may represent "A and / or B". Thus, "A / B" may represent "only A", "only B", or "both A and B". For example, "A, B, C" may mean "A, B, or C".

[0036] In the present disclosure, "at least one of A and B" may mean "only A", "only B", or "both A and B". Additionally, the expressions "at least one of A or B" or "at least one of A and / or B" in the present disclosure may be interpreted the same as "at least one of A and B".

[0037] Additionally, in the present disclosure, "at least one of A, B, and C" may mean "only A", "only B", "only C", or "any combination of A, B, and C". Additionally, "at least one of A, B, or C" or "at least one of A, B, and / or C" may mean "at least one of A, B, and C".

[0038] Additionally, the parentheses used in the present disclosure may mean "for example". Specifically, when shown as "control information (PDCCH)", "PDCCH" may be cited as an example of "control information". In other words, in the present disclosure, "control information" is not limited to "PDCCH", and "PDCCH" may be cited as an example of "control information". Additionally, even when shown as "control information (i.e., PDCCH)", "PDCCH" may be cited as an example of "control information".

[0039] The technical features separately described in one figure in the present disclosure may be implemented separately or simultaneously.

[0040] Although not limited thereto, the various descriptions, functions, processes, suggestions, methods, and / or operation flowcharts of the present disclosure disclosed herein may be applied to various fields that require wireless communication and / or connection (e.g., 5G) between devices.

[0041] Hereinafter, the present disclosure will be described in more detail with reference to the accompanying drawings. Unless otherwise specified, the same reference numerals in the following drawings and / or descriptions may refer to the same and / or corresponding hardware blocks, software blocks, and / or functional blocks.

[0042] Figure 1 An example of a communication system to which an implementation manner of the present disclosure is applied is shown.

[0043] Figure 1 The 5G usage scenarios shown are merely exemplary, and the technical features of the present disclosure can be applied to Figure 1 other 5G usage scenarios not shown herein.

[0044] The three main requirement categories of 5G include: (1) the category of enhanced mobile broadband (eMBB), (2) the category of massive machine type communication (mMTC), and (3) the category of ultra-reliable and low-latency communication (URLLC).

[0045] Referring to Figure 1 , communication system 1 includes wireless devices 100a to 100f, a base station (BS) 200, and a network 300. Although Figure 1 a 5G network is illustrated as an example of the network of communication system 1, the implementation of the present disclosure is not limited to 5G systems and can be applied to future communication systems other than 5G systems.

[0046] BS 200 and network 300 can be implemented as wireless devices, and a specific wireless device can operate as a BS / network node relative to other wireless devices.

[0047] Wireless devices 100a to 100f represent devices that perform communication using a radio access technology (RAT) (e.g., 5G NR or LTE) and can be referred to as communication / radio / 5G devices. Wireless devices 100a to 100f can include, but are not limited to, robot 100a, vehicles 100b-1 and 100b-2, extended reality (XR) device 100c, handheld device 100d, household appliance 100e, Internet of Things (IoT) device 100f, and artificial intelligence (AI) device / server 400. For example, a vehicle can include a vehicle with wireless communication capabilities, an autonomous driving vehicle, and a vehicle capable of performing communication between vehicles. A vehicle can include an unmanned aerial vehicle (UAV) (e.g., a drone). An XR device can include an augmented reality (AR) / virtual reality (VR) / mixed reality (MR) device and can be implemented in the form of a head-mounted device (HMD), a head-up display (HUD) mounted in a vehicle, a TV, a smart phone, a computer, a wearable device, a household appliance device, a digital sign, a vehicle, a robot, etc. A handheld device can include a smart phone, a smart tablet, a wearable device (e.g., a smart watch or smart glasses), and a computer (e.g., a notebook). A household appliance can include a TV, a refrigerator, and a washing machine. An IoT device can include sensors and smart meters.

[0048] In the present disclosure, the wireless devices 100a to 100f may be referred to as user equipment (UE). The UE may include, for example, a cellular phone, a smart phone, a laptop computer, a digital broadcast terminal, a personal digital assistant (PDA), a portable multimedia player (PMP), a navigation system, a tablet personal computer (PC), a tablet PC, a superbook, a vehicle, a vehicle with an autonomous driving function, a connected car, a UAV, an AI module, a robot, an AR device, a VR device, an MR device, a hologram device, a public safety device, an MTC device, an IoT device, a medical device, a FinTech device (or a financial device), a security device, a weather / environment device, a device related to 5G services, or a device related to the fourth industrial revolution field.

[0049] The wireless devices 100a to 100f may be connected to the network 300 via the BS200. AI technology may be applied to the wireless devices 100a to 100f, and the wireless devices 100a to 100f may be connected to the AI server 400 via the network 300. The network 300 may be configured using a 3G network, a 4G (e.g., LTE) network, a 5G (e.g., NR) network, and a super 5G network. Although the wireless devices 100a to 100f may communicate with each other through the BS200 / network 300, the wireless devices 100a to 100f may perform direct communication (e.g., sidelink communication) with each other without going through the BS200 / network 300. For example, the vehicles 100b-1 and 100b-2 may perform direct communication (e.g., vehicle-to-vehicle (V2V) / vehicle-to-everything (V2X) communication). The IoT devices (e.g., sensors) may perform direct communication with other IoT devices (e.g., sensors) or other wireless devices 100a to 100f.

[0050] Wireless communications / connections 150a, 150b, and 150c can be established between wireless devices 100a to 100f and / or between wireless devices 100a to 100f and BS 200 and / or between BS 200s. Here, the wireless communications / connections can be established via various RATs (e.g., 5G NR) such as uplink / downlink communication 150a, sidelink communication (or device-to-device (D2D) communication) 150b, inter-base station communication 150c (e.g., relay, integrated access and backhaul (IAB)). The wireless devices 100a to 100f and BS 200 / wireless devices 100a to 100f can send radio signals to / from each other via the wireless communications / connections 150a, 150b, and 150c. For example, the wireless communications / connections 150a, 150b, and 150c can send / receive signals via various physical channels. To this end, at least a part of various configuration information configuration processes, various signal processing processes (e.g., channel encoding / decoding, modulation / demodulation, and resource mapping / demapping), and resource allocation processes for sending / receiving radio signals can be performed based on various proposals of the present disclosure.

[0051] NR supports multiple numerologies (and / or multiple subcarrier spacings (SCSs)) to support various 5G services. For example, if the SCS is 15 kHz, wide area can be supported in the traditional cellular band, while if the SCS is 30 kHz / 60 kHz, dense urban areas, lower latency, and wider carrier bandwidth can be supported. If the SCS is 60 kHz or higher, a bandwidth greater than 24.25 GHz can be supported to overcome phase noise.

[0052] NR frequency bands can be defined as two types of frequency ranges, namely, frequency range 1 (FR1) and frequency range 2 (FR2). The numerical values of the frequency ranges can change. For example, the two types (FR1 and FR2) of frequency ranges can be as shown in Table 1 below. For ease of explanation, in the frequency ranges used in the NR system, FR1 can represent "the range below 6 GHz", FR2 can represent "the range above 6 GHz", and can be referred to as millimeter wave (mmW).

[0053] [Table 1]

[0054] Frequency Range Name Corresponding Frequency Range Subcarrier Spacing FR1 450MHz - 6000MHz 15, 30, 60kHz FR2 24250MH - 52600MHz 60, 120, 240kHz

[0055] As described above, the numerical value of the frequency range of the NR system can be changed. For example, FR1 may include a frequency band of 410 MHz to 7125 MHz as shown in Table 2 below. That is, FR1 may include a frequency band of 6 GHz (or 5850 MHz, 5900 MHz, 5925 MHz, etc.) or higher. For example, a frequency band of 6 GHz (or 5850 MHz, 5900 MHz, 5925 MHz, etc.) or more included in FR1 may include an unlicensed frequency band. The unlicensed frequency band may be used for various purposes, for example, for communication of vehicles (e.g., autonomous driving).

[0056] [Table 2]

[0057] Frequency Range Name Corresponding Frequency Range Subcarrier Spacing FR1 410MHz - 7125MHz 15, 30, 60kHz FR2 24250MHz - 52600MHz 60, 120, 240kHz

[0058] Here, the radio communication technology implemented in the wireless device in the present disclosure may include narrowband Internet of Things (NB-IoT) technology for low power communication and LTE, NR and 6G. For example, NB-IoT technology may be an example of low power wide area network (LPWAN) technology, which may be implemented in specifications such as LTE Cat NB1 and / or LTE Cat NB2, and may not be limited to the above names. Additionally and / or alternatively, the radio communication technology implemented in the wireless device in the present disclosure may communicate based on LTE-M technology. For example, LTE-M technology may be an example of LPWAN technology, and may be called by various names such as enhanced machine type communication (eMTC). For example, LTE-M technology may be implemented in at least one of various specifications, such as 1) LTE Cat 0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTE non-bandwidth limited (non-BL), 5) LTE-MTC, 6) LTE machine type communication and / or 7) LTE M, and may not be limited to the above names. Additionally and / or alternatively, the radio communication technology implemented in the wireless device in the present disclosure may include at least one of ZigBee, Bluetooth, and / or LPWAN considering low power communication, and may not be limited to the above names. For example, ZigBee technology may generate a personal area network (PAN) associated with small / low power digital communication based on various specifications (such as IEEE 802.15.4), and may be referred to as various names. Figure 2 An example of a wireless device to which an implementation of the present disclosure is applied is shown.

[0059] exist Figure 2 In the embodiment, the first wireless device 100 and / or the second wireless device 200 may be implemented in various forms according to the usage / service. For example, {the first wireless device 100 and the second wireless device 200} may correspond to Figure 1at least one of {wireless devices 100a to 100f and BS200}, {wireless devices 100a to 100f and wireless devices 100a to 100f}, and / or {BS200 and BS200}. The first wireless device 100 and / or the second wireless device 200 may be configured by various elements, devices / components, and / or modules.

[0060] The first wireless device 100 may include at least one transceiver (e.g., transceiver 106), at least one processing chip (e.g., processing chip 101), and / or one or more antennas 108.

[0061] The processing chip 101 may include at least one processor (e.g., processor 102) and at least one memory (e.g., memory 104). Additionally and / or alternatively, the memory 104 may be placed outside the processing chip 101.

[0062] The processor 102 may control the memory 104 and / or the transceiver 106, and may be adapted to implement the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts described in the present disclosure. For example, the processor 102 may process the information in the memory 104 to generate a first information / signal, and then transmit a radio signal including the first information / signal through the transceiver 106. The processor 102 may receive a radio signal including a second information / signal through the transceiver 106, and then store the information obtained by processing the second information / signal in the memory 104.

[0063] The memory 104 may be operatively connected to the processor 102. The memory 104 may store various types of information and / or instructions. The memory 104 may store firmware and / or software code 105 that implements codes, commands, and / or command sets that, when executed by the processor 102, execute the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts disclosed in the present disclosure. For example, the firmware and / or software code 105 may implement instructions that, when executed by the processor 102, execute the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts disclosed in the present disclosure. For example, the firmware and / or software code 105 may control the processor 102 to execute one or more protocols. For example, the firmware and / or software code 105 may control the processor 102 to execute one or more layers of wireless interface protocols.

[0064] In this document, the processor 102 and the memory 104 can be part of a communication modem / circuit / chip designed to implement a RAT (e.g., LTE or NR). The transceiver 106 can be connected to the processor 102 and transmit and / or receive radio signals via one or more antennas 108. Each transceiver 106 can include a transmitter and / or a receiver. The transceiver 106 can be used interchangeably with the radio frequency (RF) unit. In the present disclosure, the first wireless device 100 can represent a communication modem / circuit / chip.

[0065] The second wireless device 200 can include at least one transceiver (e.g., transceiver 206), at least one processing chip (e.g., processing chip 201), and / or one or more antennas 208.

[0066] The processing chip 201 can include at least one processor (e.g., processor 202) and at least one memory (e.g., memory 204). Additionally and / or alternatively, the memory 204 can be placed outside the processing chip 201.

[0067] The processor 202 can control the memory 204 and / or the transceiver 206, and can be adapted to implement the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts described in the present disclosure. For example, the processor 202 can process the information within the memory 204 to generate a third information / signal, and then transmit a radio signal including the third information / signal via the transceiver 206. The processor 202 can receive a radio signal including a fourth information / signal via the transceiver 106, and then store the information obtained by processing the fourth information / signal in the memory 204.

[0068] The memory 204 can be operatively connected to the processor 202. The memory 204 can store various types of information and / or instructions. The memory 204 can store firmware and / or software code 205 that implements the code, commands, and / or command sets that, when executed by the processor 202, execute the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts disclosed in the present disclosure. For example, the firmware and / or software code 205 can implement instructions that, when executed by the processor 202, execute the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts disclosed in the present disclosure. For example, the firmware and / or software code 205 can control the processor 202 to execute one or more protocols. For example, the firmware and / or software code 205 can control the processor 202 to execute one or more layers of wireless interface protocols.

[0069] In this document, the processor 202 and the memory 204 can be part of a communication modem / circuit / chip designed to implement a RAT (e.g., LTE or NR). The transceiver 206 can be connected to the processor 202 and send and / or receive radio signals via one or more antennas 208. Each of the transceivers 206 can include a transmitter and / or a receiver. The transceiver 206 can be used interchangeably with the RF unit. In this disclosure, the second wireless device 200 can represent a communication modem / circuit / chip.

[0070] Hereinafter, the hardware elements of the wireless devices 100 and 200 will be described in more detail. One or more protocol layers can be implemented by, but not limited to, one or more processors 102 and 202. For example, one or more processors 102 and 202 can implement one or more layers (e.g., functional layers such as the physical (PHY) layer, the media access control (MAC) layer, the radio link control (RLC) layer, the packet data convergence protocol (PDCP) layer, the radio resource control (RRC) layer, and the service data adaptation protocol (SDAP) layer). One or more processors 102 and 202 can generate one or more protocol data units (PDUs), one or more service data units (SDUs), messages, control information, data, or information according to the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts disclosed in this disclosure. One or more processors 102 and 202 can generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data, or information according to the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts disclosed in this disclosure and provide the generated signals to one or more transceivers 106 and 206. One or more processors 102 and 202 can receive signals (e.g., baseband signals) from one or more transceivers 106 and 206 and obtain PDUs, SDUs, messages, control information, data, or information according to the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts disclosed in this disclosure.

[0071] One or more processors 102 and 202 may be referred to as a controller, microcontroller, microprocessor, or microcomputer. One or more processors 102 and 202 may be implemented by hardware, firmware, software, or a combination thereof. As an example, one or more application specific integrated circuits (ASICs), one or more digital signal processors (DSPs), one or more digital signal processing devices (DSPDs), one or more programmable logic devices (PLDs), or one or more field programmable gate arrays (FPGAs) may be included in one or more processors 102 and 202. For example, one or more processors 102 and 202 may be configured by a group of communication control processors, application processors (APs), electronic control units (ECUs), central processing units (CPUs), graphics processing units (GPUs), and memory control processors.

[0072] One or more memories 104 and 204 may be connected to one or more processors 102 and 202 and store various types of data, signals, messages, information, programs, code, instructions, and / or commands. One or more memories 104 and 204 may be configured by random access memory (RAM), dynamic RAM (DRAM), read only memory (ROM), electrically erasable programmable read only memory (EPROM), flash memory, volatile memory, non-volatile memory, hard disk drives, registers, cache memory, computer readable storage media, and / or combinations thereof. One or more memories 104 and 204 may be located inside and / or outside one or more processors 102 and 202. One or more memories 104 and 204 may be connected to one or more processors 102 and 202 by various techniques such as wired connections or wireless connections.

[0073] One or more transceivers 106 and 206 may transmit user data, control information, and / or radio signals / channels mentioned in the descriptions, functions, procedures, suggestions, methods, and / or operational flowcharts disclosed in the present disclosure to one or more other devices. One or more transceivers 106 and 206 may receive user data, control information, and / or radio signals / channels mentioned in the descriptions, functions, procedures, suggestions, methods, and / or operational flowcharts disclosed in the present disclosure from one or more other devices. For example, one or more transceivers 106 and 206 may be connected to one or more processors 102 and 202 and transmit and receive radio signals. For example, one or more processors 102 and 202 may execute control so that one or more transceivers 106 and 206 can send user data, control information, or radio signals to one or more other devices. One or more processors 102 and 202 may execute control so that one or more transceivers 106 and 206 can receive user data, control information, or radio signals from one or more other devices.

[0074] One or more transceivers 106 and 206 may be connected to one or more antennas 108 and 208. Additionally or alternatively, one or more transceivers 106 and 206 may include one or more antennas 108 and 208. One or more transceivers 106 and 206 may be adapted to transmit and receive user data, control information, and / or radio signals / channels mentioned in the descriptions, functions, procedures, suggestions, methods, and / or operational flowcharts disclosed in the present disclosure via one or more antennas 108 and 208. In the present disclosure, one or more antennas 108 and 208 may be multiple physical antennas or multiple logical antennas (e.g., antenna ports).

[0075] One or more transceivers 106 and 206 may convert received user data, control information, radio signals / channels, etc. from RF band signals to baseband signals to facilitate processing of the received user data, control information, radio signals / channels, etc. by one or more processors 102 and 202. One or more transceivers 106 and 206 may convert user data, control information, radio signals / channels, etc. processed using one or more processors 102 and 202 from baseband signals to RF band signals. To this end, one or more transceivers 106 and 206 may include (analog) oscillators and / or filters. For example, one or more transceivers 106 and 206 may up-convert an OFDM baseband signal to an OFDM signal via their (analog) oscillators and / or filters under the control of one or more processors 102 and 202 and transmit the up-converted OFDM signal at a carrier frequency. One or more transceivers 106 and 206 may receive an OFDM signal at the carrier frequency and down-convert the OFDM signal to an OFDM baseband signal via their (analog) oscillators and / or filters under the control of one or more processors 102 and 202.

[0076] Although Figure 2 not shown in, wireless devices 100 and 200 may also include additional components. The additional components 140 may be configured differently depending on the types of the wireless devices 100 and 200. For example, the additional components 140 may include at least one of a power supply unit / battery, input / output (I / O) devices (e.g., audio I / O ports, video I / O ports), a driving device, and a computing device. The additional components 140 may be coupled to one or more processors 102 and 202 via various techniques such as wired or wireless connections.

[0077] In an implementation of the present disclosure, the UE may be used as a transmitting device in the uplink (UL) and a receiving device in the downlink (DL). In an implementation of the present disclosure, the BS may be used as a receiving device in the UL and a transmitting device in the DL. Hereinafter, for ease of description, it is mainly assumed that the first wireless device 100 is used as the UE and the second wireless device 200 is used as the BS. For example, a processor 102 connected to, mounted on, or initiated in the first wireless device 100 may be adapted to perform UE behavior according to an implementation of the present disclosure or control a transceiver 106 to perform UE behavior according to an implementation of the present disclosure. A processor 202 connected to, mounted on, or initiated in the second wireless device 200 may be adapted to perform BS behavior according to an implementation of the present disclosure or control a transceiver 206 to perform BS behavior according to an implementation of the present disclosure.

[0078] In the present disclosure, the BS is also referred to as Node B (NB), eNode B (eNB), or gNB.

[0079] Figure 3 An example of a UE in which an implementation of the present disclosure is applied is shown.

[0080] Referring to Figure 3 , UE 100 may correspond to Figure 2 the first wireless device 100 of

[0081] UE 100 includes a processor 102, a memory 104, a transceiver 106, one or more antennas 108, a power management module 141, a battery 142, a display 143, a keypad 144, a subscriber identity module (SIM) card 145, a speaker 146, and a microphone 147.

[0082] The processor 102 may be adapted to implement the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts disclosed in the present disclosure. The processor 102 may be adapted to control one or more other components of the UE 100 to implement the descriptions, functions, processes, suggestions, methods, and / or operation flowcharts disclosed in the present disclosure. The radio interface protocol layer may be implemented in the processor 102. The processor 102 may include an ASIC, other chip sets, logic circuits, and / or data processing devices. The processor 102 may be an application processor. The processor 102 may include at least one of a digital signal processor (DSP), a central processing unit (CPU), a graphics processing unit (GPU), and a modem (modulator and demodulator). Examples of the processor 102 may be found in the SNAPDRAGON TM series processors manufactured by the EXYNOS TM series processors manufactured by a series of processors manufactured by the HELIO TM series processors manufactured by the ATOM TM series processors manufactured by or corresponding next-generation processors.

[0083] Memory 104 is coupled to processor 102 during operation and stores various information for operating processor 102. Memory 104 may include ROM, RAM, flash memory, memory cards, storage media, and / or other storage devices. When the implementation is realized in software, the techniques described herein may be implemented using modules (e.g., procedures, functions, etc.) that execute the descriptions, functions, procedures, suggestions, methods, and / or operation flowcharts disclosed in the present disclosure. The modules may be stored in memory 104 and implemented by processor 102. Memory 104 may be implemented within processor 102 or outside processor 102 (in which case, the memory may be communicatively coupled to processor 102 via various means known in the art).

[0084] Transceiver 106 is coupled to processor 102 during operation and transmits and / or receives radio signals. Transceiver 106 includes a transmitter and a receiver. Transceiver 106 may include baseband circuitry for processing radio frequency signals. Transceiver 106 controls one or more antennas 108 to transmit and / or receive radio signals.

[0085] Power management module 141 manages the power of processor 102 and / or transceiver 106. Battery 142 supplies power to power management module 141.

[0086] Display 143 outputs the results processed by processor 102. Keypad 144 receives inputs to be used by processor 102. Keypad 144 may be displayed on display 143.

[0087] SIM card 145 is an integrated circuit designed to securely store the International Mobile Subscriber Identity (IMSI) number and its associated keys, which are used to identify and authenticate subscribers on mobile phone devices such as mobile phones and computers. Contact information may also be stored on many SIM cards.

[0088] Speaker 146 outputs the sound-related results processed by processor 102. Microphone 147 receives the sound-related inputs to be used by processor 102.

[0089] Figure 4 and Figure 5 An example of a protocol stack in a 3GPP-based wireless communication system implementing the embodiments of the present disclosure is shown.

[0090] Specifically, Figure 4 An example of the radio interface user plane protocol stack between the UE and the BS is illustrated, and Figure 5 An example of the radio interface control plane protocol stack between the UE and the BS is illustrated. The control plane refers to the path for transmitting control messages used for call management by the UE and the network. The user plane refers to the path for transmitting data generated in the application layer (e.g., voice data or Internet packet data). Refer toFigure 4 , the user plane protocol stack can be divided into Layer 1 (i.e., the PHY layer) and Layer 2. Refer to Figure 5 , the control plane protocol stack can be divided into Layer 1 (i.e., the PHY layer), Layer 2, Layer 3 (e.g., the RRC layer), and the non-access stratum (NAS) layer. Layer 1, Layer 2, and Layer 3 are referred to as the access stratum (AS).

[0091] In the 3GPP LTE system, Layer 2 is separated into the following sub-layers: MAC, RLC, and PDCP. In the 3GPP NR system, Layer 2 is separated into the following sub-layers: MAC, RLC, PDCP, and SDAP. The PHY layer provides a transport channel to the MAC sub-layer, the MAC sub-layer provides a logical channel to the RLC sub-layer, the RLC sub-layer provides an RLC channel to the PDCP sub-layer, and the PDCP sub-layer provides a radio bearer to the SDAP sub-layer. The SDAP sub-layer provides a quality of service (QoS) flow to the 5G core network.

[0092] In the 3GPP NR system, the main services and functions of the MAC sub-layer include: mapping between logical channels and transport channels; multiplexing MAC SDUs belonging to one or different logical channels onto / from transport blocks (TBs) delivered to / from the physical layer on the transport channel; scheduling information reporting; error correction via hybrid automatic repeat request (HARQ) (one HARQ entity per cell in the case of carrier aggregation (CA)); priority handling between UEs via dynamic scheduling; priority handling between the logical channels of a single UE via logical channel prioritization; padding. A single MAC entity can support multiple parameter sets, transmission timings, and cells. The mapping restrictions in logical channel prioritization control which parameter set(s), cell, and transmission timing a logical channel can use.

[0093] The MAC provides different types of data transfer services. To accommodate different types of data transfer services, multiple types of logical channels are defined, i.e., each logical channel supports the transfer of a specific type of information. Each logical channel type is defined by what type of information is transferred. Logical channels are divided into two groups: control channels and traffic channels. Control channels are only used for the transfer of control plane information, and traffic channels are only used for the transfer of user plane information. The Broadcast Control Channel (BCCH) is a downlink logical channel for broadcasting system control information, the Paging Control Channel (PCCH) is a downlink logical channel for transmitting paging information, system information change notifications, and indications of ongoing Public Warning Service (PWS) broadcasts, the Common Control Channel (CCCH) is a logical channel for sending control information between the UE and the network and for UEs without an RRC connection to the network, and the Dedicated Control Channel (DCCH) is a point-to-point two-way logical channel for sending dedicated control information between the UE and the network and used by UEs with an RRC connection. The Dedicated Traffic Channel (DTCH) is a point-to-point logical channel dedicated to one UE and is used to transfer user information. The DTCH can exist in both the uplink and the downlink. In the downlink, there are the following connections between logical channels and transport channels: BCCH can be mapped to the Broadcast Channel (BCH); BCCH can be mapped to the Downlink Shared Channel (DL-SCH); PCCH can be mapped to the Paging Channel (PCH); CCCH can be mapped to DL-SCH; DCCH can be mapped to DL-SCH; and DTCH can be mapped to DL-SCH. In the uplink, there are the following connections between logical channels and transport channels: CCCH can be mapped to the Uplink Shared Channel (UL-SCH); DCCH can be mapped to UL-SCH; and DTCH can be mapped to UL-SCH.

[0094] The RLC sublayer supports three transfer modes: Transparent Mode (TM), Unacknowledged Mode (UM), and Acknowledged Mode (AM). RLC configuration is for each logical channel and is independent of the parameter set and / or transfer duration. In the 3GPP NR system, the main services and functions of the RLC sublayer depend on the transfer mode and include: transfer of upper layer PDUs; sequence numbering independent of the one in PDCP (UM and AM); error correction via ARQ (only AM); segmentation (AM and UM) and re-segmentation (only AM) of RLC SDUs; reassembly of SDUs (AM and UM); duplicate detection (only AM); RLC SDU discard (AM and UM); RLC re-establishment; protocol error detection (only AM).

[0095] In the 3GPP NR system, the main services and functions of the PDCP sublayer for the user plane include: sequence numbering; header compression and decompression using robust header compression (ROHC); transfer of user data; reordering and duplicate detection; in-sequence delivery; PDCP PDU routing (in the case of split bearers); retransmission of PDCP SDUs; encryption, decryption, and integrity protection; PDCP SDU discard; PDCP re-establishment and data recovery for RLC AM; PDCP status reporting for RLC AM; duplication of PDCP PDUs and indication of duplicate discard to the lower layer. The main services and functions of the PDCP sublayer for the control plane include: sequence numbering; encryption, decryption, and integrity protection; transfer of control plane data; reordering and duplicate detection; in-sequence delivery; duplication of PDCP PDUs and indication of duplicate discard to the lower layer.

[0096] In the 3GPP NR system, the main services and functions of SDAP include: mapping of QoS flows to data radio bearers; marking of QoS flow ID (QFI) in both DL packets and UL packets. A single SDAP protocol entity is configured for each individual PDU session.

[0097] In the 3GPP NR system, the main services and functions of the RRC sublayer include: broadcasting of system information related to AS and NAS; paging initiated by 5GC or NG-RAN; establishment, maintenance, and release of the RRC connection between the UE and NG-RAN; security functions including key management; establishment, configuration, maintenance, and release of signaling radio bearers (SRBs) and data radio bearers (DRBs); mobility functions (including: handover and context transfer; UE cell selection and reselection and control of cell selection and reselection; inter-RAT mobility); QoS management functions; control of UE measurement reporting and reporting; detection and repair of radio link failures; transfer of NAS messages from the UE to the NAS / from the NAS to the UE.

[0098] Figure 6 A frame structure in a 3GPP-based wireless communication system implementing the embodiments of the present disclosure is shown.

[0099] Figure 6The frame structure shown is merely exemplary, and the number of sub-frames, the number of time slots, and / or the number of symbols in a frame may be changed differently. In a 3GPP-based wireless communication system, OFDM parameter sets (e.g., subcarrier spacing (SCS), transmission time interval (TTI) duration) may be configured differently among multiple cells aggregated for one UE. For example, if a UE is configured with different SCSs for cells for cell aggregation, the (absolute time) duration of a time resource (e.g., sub-frame, time slot, or TTI) including the same number of symbols may be different among the aggregated cells. In this document, a symbol may include an OFDM symbol (or CP-OFDM symbol), an SC-FDMA symbol (or discrete Fourier transform-spread-OFDM (DFT-s-OFDM) symbol).

[0100] Refer to Figure 6 , downlink and uplink transmissions are organized into frames. Each frame has a duration of T f = 10 ms. Each frame is divided into two half-frames, where each half-frame has a duration of 5 ms. Each half-frame includes 5 sub-frames, where the duration T sf of each sub-frame is 1 ms. Each sub-frame is divided into time slots, and the number of time slots in a sub-frame depends on the subcarrier spacing. Each time slot includes 14 or 12 OFDM symbols based on a cyclic prefix (CP). In normal CP, each time slot includes 14 OFDM symbols, and in extended CP, each time slot includes 12 OFDM symbols. The parameter set is based on an exponentially scalable subcarrier spacing βf = 2 u * 15 kHz.

[0101] Table 3 shows the number of OFDM symbols N u in each time slot, the number of time slots N slot symb in each frame, and the number of time slots N frame，u slot in each sub-frame according to the subcarrier spacing βf = 2 subframe，u slot .

[0102] [Table 3]

[0103] u <![CDATA[N slot symb > <![CDATA[N frame，u slot > <![CDATA[N subframe,u slot > 0 14 10 1 1 14 20 2 2 14 40 4 3 14 80 8 4 14 1 60 16

[0104] Table 4 shows the number of OFDM symbols N u in each time slot, the number of time slots N slot symb in each frame, and the number of time slots N frame，u slot in each sub-frame according to the subcarrier spacing βf = 2subframe，u slot .

[0105] [Table 4]

[0106] u <![CDATA[N slot symb > <![CDATA[N frame，u slot > <![CDATA[N subframe,u slot > 2 1 2 40 4

[0107] A time slot includes a plurality of symbols in the time domain (e.g., 14 or 12 symbols). For each parameter set (e.g., subcarrier spacing) and carrier, a resource grid of N subcarriers and N OFDM symbols starting from a common resource block (CRB) N indicated by higher layer signaling (e.g., RRC signaling) is defined, where N is the number of resource blocks (RBs) in the resource grid, and the subscript x is DL for downlink and UL for uplink. N is the number of subcarriers per RB. In a 3GPP-based wireless communication system, N is generally 12. For a given antenna port p, subcarrier spacing configuration u, and transmission direction (DL or UL), there is a resource grid. The carrier bandwidth N of the subcarrier spacing configuration u is given by higher layer parameters (e.g., RRC parameters). Each element in the resource grid for antenna port p and subcarrier spacing configuration u is called a resource element (RE), and a complex symbol can be mapped to each RE. Each RE in the resource grid is uniquely identified by an index k in the frequency domain and an index l representing the symbol position relative to a reference point in the time domain. In a 3GPP-based wireless communication system, an RB is defined by 12 consecutive subcarriers in the frequency domain. As start,u grid starting from size，u grid，x *N RB sc subcarriers and N subframe，u symb OFDM symbols is defined, where N size,u grid,x is the number of resource blocks (RBs) in the resource grid, and the subscript x is DL for downlink and UL for uplink. N RB sc is the number of subcarriers per RB. In a 3GPP-based wireless communication system, N RB sc is generally 12. For a given antenna port p, subcarrier spacing configuration u, and transmission direction (DL or UL), there is a resource grid. The carrier bandwidth N of the subcarrier spacing configuration u is given by higher layer parameters (e.g., RRC parameters). Each element in the resource grid for antenna port p and subcarrier spacing configuration u is called a resource element (RE), and a complex symbol can be mapped to each RE. Each RE in the resource grid is uniquely identified by an index k in the frequency domain and an index l representing the symbol position relative to a reference point in the time domain. In a 3GPP-based wireless communication system, an RB is defined by 12 consecutive subcarriers in the frequency domain. As size,u grid given by higher layer parameters (e.g., RRC parameters). Each element in the resource grid for antenna port p and subcarrier spacing configuration u is called a resource element (RE), and a complex symbol can be mapped to each RE. Each RE in the resource grid is uniquely identified by an index k in the frequency domain and an index l representing the symbol position relative to a reference point in the time domain. In a 3GPP-based wireless communication system, an RB is defined by 12 consecutive subcarriers in the frequency domain. As Figure 6As shown, when the SCS is doubled, the slot length and symbol length are halved. For example, when the SCS is 15 kHz, the slot length is 1 ms, which is the same as the subframe length. When the SCS is 30 kHz, the slot length is 0.5 ms (= 500 us), and the symbol length is half of the symbol length when the SCS is 15 kHz. When the SCS is 60 kHz, the slot length is 0.25 ms (= 250 us), and the symbol length is half of the symbol length when the SCS is 30 kHz. When the SCS is 120 kHz, the slot length is 0.125 ms (= 125 us), and the symbol length is half of the symbol length when the SCS is 60 kHz. When the SCS is 240 kHz, the slot length is 0.0625 ms (= 62.5 us), and the symbol length is half of the symbol length when the SCS is 120 kHz.

[0108] In the 3GPP NR system, RBs are classified into CRBs and physical resource blocks (PRBs). For the subcarrier spacing configuration u, the CRBs are numbered upward from 0 in the frequency domain. The center of subcarrier 0 of CRB0 for the subcarrier spacing configuration u coincides with "Point A" which is a common reference point for the resource block grid. In the 3GPP NR system, PRBs are defined within a bandwidth part (BWP) and numbered from 0 to N size BWP,i -1, where i is the number of bandwidth parts. The physical resource block n in bandwidth part i PRB is related to the common resource block n CRB as follows: n PRB = n CRB + N size BWP,i , where N size BWP,i is the common resource block from which the bandwidth part starts with respect to CRB0. A BWP includes a plurality of consecutive RBs. A carrier can include up to N (e.g., 5) BWPs. A UE can be configured with one or more BWPs on a given component carrier. Only one of the multiple BWPs configured for the UE can be activated at a time. The active BWP defines the operating bandwidth of the UE within the operating bandwidth of the cell.

[0109] In the present disclosure, the term "cell" may refer to a geographical area provided by one or more nodes for a communication system or may refer to radio resources. A "cell" as a geographical area can be understood as the coverage area within which a node can provide services using a carrier, and as radio resources (e.g., time-

[0110] A "cell" associated with frequency resources is associated with the bandwidth of the frequency range configured by a carrier. A "cell" associated with radio resources is defined by a combination of downlink resources and uplink resources (e.g., a combination of a DL component carrier (CC) and a UL CC). A cell can be configured by only downlink resources or can be configured by both downlink resources and uplink resources. Since the DL coverage (which is the range within which a node can transmit a valid signal) and the UL coverage (which is the range within which a node can receive a valid signal from a UE) depend on the carrier carrying the signal, the coverage of a node can be associated with the coverage of the "cell" of the radio resources used by the node. Thus, the term "cell" can sometimes be used to represent the service coverage of a node, at other times the radio resources, or at other times the range within which a signal using the radio resources can reach with an effective strength.

[0111] In CA, two or more CCs are aggregated. The UE can receive or transmit on one or more CCs simultaneously according to its capabilities. CA is supported for both contiguous CCs and non - contiguous CCs. When CA is configured, the UE has only one RRC connection with the network. At RRC connection establishment / re - establishment / handoff, one serving cell provides NAS mobility information, and at RRC connection re - establishment / handoff, one serving cell provides security input. This cell is called the primary cell (PCell). The PCell is a cell operating on the primary frequency where the UE performs the initial connection establishment process or initiates the connection re - establishment process. Depending on the UE capabilities, secondary cells (SCells) can be configured to form a set of serving cells together with the PCell. An SCell is a cell that provides additional radio resources on top of a special cell (SpCell). Thus, the set of configured serving cells for a UE always consists of one PCell and one or more SCells. For dual - connectivity (DC) operation, the term SpCell refers to the PCell of the master cell group (MCG) or the primary SCell (PSCell) of the secondary cell group (SCG). The SpCell supports PUCCH transmission and contention - based random access and is always active. The MCG is a group of serving cells associated with the master node, which includes the SpCell (PCell) and optionally one or more SCells. For a UE configured with DC, the SCG is a subset of serving cells associated with the secondary node, which includes the PSCell and zero or more SCells. For an RRC_CONNECTED UE not configured with CA / DC, there is only one serving cell consisting of the PCell. For an RRC_CONNECTED UE configured with CA / DC, the term "serving cell" is used to represent the set of cells consisting of the SpCell and all SCells. In DC, two MAC entities are configured in the UE: one for the MCG and one for the SCG.

[0112] Figure 7 FIG. shows an example of data flow in a 3GPP NR system implementing the present disclosure.

[0113] Refer to Figure 7 ,"RB" represents radio bearer, and "H" represents header. Radio bearers are classified into two groups: DRBs for user - plane data and SRBs for control - plane data. MAC PDUs are sent / received to / from external devices through the PHY layer using radio resources. The MAC PDU arrives at the PHY layer in the form of transport blocks.

[0114] In the PHY layer, the uplink transmission channels UL-SCH and RACH are respectively mapped to their physical channels, the Physical Uplink Shared Channel (PUSCH) and the Physical Random Access Channel (PRACH), and the downlink transmission channels DL-SCH, BCH, and PCH are respectively mapped to the Physical Downlink Shared Channel (PDSCH), the Physical Broadcast Channel (PBCH), and the PDSCH. In the PHY layer, the Uplink Control Information (UCI) is mapped to the Physical Uplink Control Channel (PUCCH), and the Downlink Control Information (DCI) is mapped to the Physical Downlink Control Channel (PDCCH). The UE sends the MAC PDU related to UL-SCH via the PUSCH based on the UL grant, and the BS sends the MAC PDU related to DL-SCH via the PDSCH based on the DL assignment.

[0115] In the following, the content regarding handover (HO) is described.

[0116] The handover may include a PCell change. In addition, in the present disclosure, the descriptions related to handover may also be applied to other mobility procedures, such as PSCell change (or Secondary Node (SN) change) and / or PSCell addition (or SN addition).

[0117] Figure 8 An example of a conventional handover process to which the technical features of the present disclosure can be applied is shown.

[0118] Referring to Figure 8 , in step S801, the source RAN node may send a measurement control message to the UE. The source RAN node may configure the UE measurement process according to the roaming and access restriction information and, for example, the available multi-band information through the measurement control message. The measurement control information provided by the source RAN node through the measurement control message may assist in controlling the function of the UE's connection mobility. For example, the measurement control message may include a measurement configuration and / or a reporting configuration.

[0119] In step S803, the UE may send a measurement report message to the source RAN node. The measurement report message may include the results of measurements on neighboring cells around the UE that can be detected by the UE. The UE may generate the measurement report message according to the measurement configuration and / or measurement control information in the measurement control message received in step S801.

[0120] In step S805, the source RAN node may make a handover (HO) decision based on the measurement report. For example, the source RAN node may make an HO decision and determine the target RAN node for HO among the neighbor cells around the UE based on the measurement results of the neighbor cells (such as cell quality, signal quality, signal strength, reference signal received power (RSRP), reference signal received quality (RSRQ), channel state, channel quality, signal-to-interference-plus-noise ratio (SINR)).

[0121] In step S807, the source RAN node may send an HO request message to the target RAN node determined in step S805. That is, the source RAN node may perform handover preparation with the target RAN node. The HO request message may include the necessary information for preparing the handover at the target RAN node.

[0122] In step S809, the target RAN node may perform admission control based on the information included in the HO request message. The target RAN node may configure and reserve the required resources (such as C-RNTI and / or RACH preamble). The AS configuration to be used in the target RAN node may be specified independently (i.e., "established"), or specified as an increment compared to the AS configuration used in the source cell (i.e., "reconfigured").

[0123] In step S811, the target RAN node may send an HO request acknowledgment (ACK) message to the source RAN node. The HO request ACK message may include information about the resources reserved and prepared for the handover. For example, the HO request ACK message may include a transparent container to be sent to the UE as an RRC message to perform the handover. The container may include a new C-RNTI, a target gNB security algorithm identifier for the selected security algorithm, a dedicated RACH preamble, and / or some other possible parameters, i.e., access parameter SIB. If RACH-less handover is configured, the container may include a timing adjustment indication and an optional pre-allocated uplink grant. If necessary, the HO request ACK message may also include RNL / TNL information for the forwarding tunnel. Once the source RAN node receives the HO request ACK message, or once the transmission of the handover command is initiated in the downlink, data forwarding may be initiated.

[0124] In step S813, the source RAN node may send a handover command to the UE. For example, the handover command may include or may be a cell configuration (i.e., an RRCReconfiguration message including ReconfigurationWithSync). The RRCReconfiguration message and / or ReconfigurationWithSync of the target cell may include information required to access the target cell (i.e., access configuration), which includes the physical cell ID of the target cell, the identifier of the UE (i.e., C-RNTI), a HO validity timer (i.e., T304 timer), a target gNB security algorithm identifier for the selected security algorithm, a dedicated RACH resource set for contention-free random access (e.g., dedicated random access preambles), the association between the RACH resource and the SSB, the association between the RACH resource and the UE-specific CSI-RS configuration, at least one of a common RACH resource or the system information of the target cell. The source RAN node may perform necessary integrity protection and encryption of the message.

[0125] In step S815, the UE may hand over to the new cell, i.e., the target RAN node. The UE may detach from the old cell (i.e., the source RAN node) and synchronize to the new cell (i.e., the target RAN node). The UE may perform the handover from the source RAN node to the target RAN node based on the applied cell configuration. For example, upon receiving the handover command, the UE may start the T304 timer and perform contention-free random access towards the target RAN node based on the dedicated RACH resource set.

[0126] In step S817, upon successful completion of the random access procedure, the UE may stop the T304 timer and send a handover complete message (i.e., an RRCReconfigurationComplete message) to the target RAN node. The UE may send an RRCReconfigurationComplete message with the C-RNTI for confirming the handover to the target RAN node to indicate that the handover procedure for the UE is completed. The target RAN node may verify the C-RNTI sent in the RRCReconfigurationComplete message. The target RAN node may now start sending data to the UE. When the random access fails and the T304 timer is still running, the UE may retry the random access towards the target RAN node. When the T304 timer expires, the UE may declare a handover failure (HOF) and perform an RRC reconstruction procedure.

[0127] Figure 9 An example of a conditional handover procedure to which the technical features of the present disclosure may be applied is shown.

[0128] Refer toFigure 9 In step S901, the source cell may send a measurement control message to the UE. The measurement control message may include a measurement configuration containing a list of measurement configurations, and each measurement configuration in the list includes a measurement identifier (ID), a corresponding measurement object, and a corresponding reporting configuration.

[0129] In step S903, the UE may send a measurement report message to the source cell. The measurement report message may include the results of measurements on neighbor cells around the UE that can be detected by the UE. The UE may generate the measurement report message based on the measurement configurations and / or measurement control information in the measurement control message received in step S901.

[0130] In step S905, the source cell may make a handover decision based on the measurement report. For example, the source cell may make a handover decision and determine candidate target cells for handover (e.g., target cell 1 and target cell 2) among the neighbor cells around the UE based on the measurement results of the neighbor cells (e.g., signal quality, reference signal received power (RSRP), reference signal received quality (RSRQ)).

[0131] In step S907, the source cell may send a handover request message to target cell 1 and target cell 2 determined in step S905. That is, the source cell may perform handover preparations with target cell 1 and target cell 2. The handover request message may include the necessary information for preparing the handover on the target side (e.g., target cell 1 and target cell 2).

[0132] In step S909, each of target cell 1 and target cell 2 may perform admission control based on the information included in the handover request message. The target cell may configure and reserve the required resources (e.g., C-RNTI and / or RACH preamble). The AS configuration to be used in the target cell may be specified independently (i.e., "established") or specified as an increment compared to the AS configuration used in the source cell (i.e., "reconfigured").

[0133] In step S911, the target cell and target cell 2 may send a handover request acknowledgment (ACK) message to the source cell. The handover request ACK message may include cell configuration (i.e., an RRCReconfiguration message including ReconfigurationWithSync), which includes information about the resources reserved and prepared for the handover. For example, the handover request ACK message may include a transparent container to be sent to the UE as an RRC message (i.e., an RRCReconfiguration message / cell configuration) to perform the handover. The container / cell configuration / RRCReconfiguration message may include the information required to access the target cell (i.e., access configuration), which includes at least one of the physical cell ID of the target cell, the identifier of the UE (i.e., C-RNTI), the HO validity timer (i.e., T304 timer), the target gNB security algorithm identifier for the selected security algorithm, the dedicated RACH resource set for contention-free random access (e.g., dedicated random access preambles), the association between the RACH resource and the SSB, the association between the RACH resource and the UE-specific CSI-RS configuration, the common RACH resource, or the system information of the target cell. If RACH-less handover is configured, the container may include a timing adjustment indication and optionally pre-allocated uplink grants. If required, the handover request ACK message may also include RNL / TNL information for the forwarding tunnel. Once the source cell receives the handover request ACK message, or once the transmission of the conditional handover command is initiated in the downlink, data forwarding may be initiated.

[0134] In step S913, the source cell may send an RRCReconfiguration message including a conditional reconfiguration to the UE. The conditional reconfiguration may also be referred to as (or may include) a conditional handover (CHO) configuration and / or a conditional handover command (e.g., a CHO command). The conditional reconfiguration may include a list of conditional reconfigurations / conditional handover commands, which includes conditional reconfigurations / conditional handover commands for each candidate target cell (e.g., target cell 1, target cell 2). For example, the conditional reconfiguration may include a conditional reconfiguration / conditional handover command for target cell 1 and a conditional reconfiguration / conditional handover command for target cell 2. The conditional reconfiguration for a target cell may include an index / identifier identifying the corresponding conditional reconfiguration, handover conditions for the target cell, and / or cell configuration for the target cell (i.e., an RRCReconfiguration message including ReconfigurationWithSync). The RRCReconfiguration message and / or ReconfigurationWithSync for a target cell may include information required to access the target cell, which includes at least one of the physical cell ID of the target cell, the identifier of the UE (i.e., C-RNTI), a HO validity timer (i.e., T304 timer), a target gNB security algorithm identifier for the selected security algorithm, a dedicated RACH resource set for contention-free random access (e.g., dedicated random access preambles), the association between the RACH resource and the SSB, the association between the RACH resource and the UE-specific CSI-RS configuration, a common RACH resource, or the system information of the target cell.

[0135] In step S915, the UE may perform an evaluation of the handover conditions for the candidate target cells (e.g., target cell 1, target cell 2) and select a target cell for handover among the candidate target cells. For example, the UE may perform measurements on the candidate target cells and determine whether the candidate target cells satisfy the handover conditions of the candidate target cells based on the results of the measurements on the candidate target cells. Alternatively, the UE may determine whether the measurement results of the target cell / target cells satisfy the handover conditions of the target cell. If the UE identifies that target cell 1 satisfies the handover conditions for target cell 1, the UE may select target cell 1 as the target cell for handover.

[0136] In step S917, the UE can detach from the old cell (i.e., the source cell) and synchronize to the new cell (i.e., the selected target cell). The UE can perform a handover from the source cell to the target cell based on the applied cell configuration. For example, upon receiving a handover command, the UE can start the T304 timer and perform contention-free random access for the target cell based on a dedicated RACH resource set.

[0137] In step S919, upon successful completion of the random access procedure, the UE can stop the T304 timer and send a handover complete message (i.e., the RRCReconfigurationComplete message) to the target cell. The UE can send an RRCReconfigurationComplete message including the C-RNTI for handover confirmation to the target cell to indicate that the handover procedure for the UE is completed. The target RAN node can verify the C-RNTI sent in the RRCReconfigurationComplete message. The target RAN node can now start sending data to the UE. When the random access fails and the T304 timer is still running, the UE can retry the random access towards the target cell. When the T304 timer expires, the UE can declare a handover failure (HOF) and perform an RRC reconstruction procedure.

[0138] In the present disclosure, a method for efficient configuration handover between a serving cell and a candidate / target cell based on a non-shared configuration part and a shared configuration part with selective configuration adjustment is proposed.

[0139] The UE can obtain multiple configuration parts configured for the UE. For example, the UE can receive multiple configuration parts from the network. The configuration parts can be used to configure a reference configuration and / or modify a configuration.

[0140] Each configuration part can be associated with one or more cells. Each configuration part can be associated with one or more cell IDs (cell indexes or physical cell IDs (PCIs)).

[0141] At least one of the following configuration parts can be configured:

[0142] - If the associated cell is a serving cell, a non-shared common configuration part applicable only to the associated cell;

[0143] - If the associated cell is a non-serving cell, a non-shared common configuration part applicable only to the associated cell;

[0144] - If the associated cell is a serving cell, a non-shared dedicated configuration part applicable only to the associated cell;

[0145] - If the associated cell is a non-serving cell, it is the non-shared dedicated configuration part that is only applicable to the associated cell;

[0146] - The shared common configuration part applicable to multiple cells (applicable cells). The shared common configuration part can have multiple shared common configuration entries. For each applicable cell, one shared common configuration entry can be associated and thus applied. For each shared common configuration entry, adjustment configuration can also be configured. Depending on whether the applicable cell is a serving cell or a non-serving cell, the adjustment configuration can be aimed at adjusting the corresponding shared common configuration entry. The adjustment configuration for the serving cell and the non-serving cell can be configured for the corresponding shared common configuration entry.

[0147] - The shared dedicated configuration part applicable to multiple cells (applicable cells). The applicable cells of the relevant shared dedicated configuration part can be indicated implicitly or explicitly. The shared dedicated configuration part can have multiple shared dedicated configuration entries. For each applicable cell, one shared dedicated configuration entry can be associated and thus applied. For each shared dedicated configuration entry, adjustment configuration can also be configured. Depending on whether the applicable cell is a serving cell or a non-serving cell, the adjustment configuration can be aimed at adjusting the corresponding shared dedicated configuration entry. The adjustment configuration for the serving cell and the non-serving cell can be configured for the corresponding shared dedicated configuration entry.

[0148] The shared configuration part can be used to configure the reference configuration. The non-shared configuration part can be used to configure the modified configuration.

[0149] The UE can determine the applicable part of the configuration based on the configuration part and which cell is the serving cell, and there may be configuration adjustments. The UE can determine the applicable part when moving to the target cell.

[0150] For each non-shared common configuration part applicable when the associated cell is a serving cell:

[0151] - If the associated cell is a serving cell, the UE can consider the configuration part to be active (i.e., the relevant configuration part is selected), or equivalently, the UE can activate the configuration part.

[0152] - If the associated cell is not a serving cell, the UE can consider the configuration part to be inactive (i.e., the relevant configuration part is not selected), or equivalently, the UE can deactivate the configuration part.

[0153] For each non-shared dedicated configuration part applicable when the associated cell is a serving cell:

[0154] - If the associated cell is the serving cell, the UE may consider the configured portion to be active (i.e., the relevant configured portion is selected), or equivalently, the UE may activate the configured portion.

[0155] - If the associated cell is not the serving cell, the UE may consider the configured portion to be inactive (i.e., the relevant configured portion is not selected), or equivalently, the UE may deactivate the configured portion.

[0156] For each non-shared common configured portion applicable when the associated cell is not the serving cell:

[0157] - If the associated cell is not the serving cell, the UE may consider the configured portion to be active (i.e., the relevant configured portion is selected), or equivalently, the UE may activate the configured portion.

[0158] - If the associated cell is the serving cell, the UE may consider the configured portion to be inactive (i.e., the relevant configured portion is not selected), or equivalently, the UE may deactivate the configured portion.

[0159] For each non-shared dedicated configured portion applicable when the associated cell is not the serving cell:

[0160] - If the associated cell is not the serving cell, the UE may consider the configured portion to be active (i.e., the relevant configured portion is selected), or equivalently, the UE may activate the configured portion.

[0161] - If the associated cell is the serving cell, the UE may consider the configured portion to be inactive (i.e., the relevant configured portion is not selected), or equivalently, the UE may deactivate the configured portion.

[0162] For each shared common configured portion, the UE may select the shared common configuration entries applicable to the serving cell and other cells based on the association between the shared common configuration entries and the applicable cells, possibly with configuration adjustments.

[0163] For each shared dedicated configured portion, the UE may select the shared dedicated configuration entries applicable to the serving cell and other cells based on the association between the shared dedicated configuration entries and the applicable cells, possibly with adjustments.

[0164] The UE may apply the determined applicable portions of the configuration. The UE may apply the determined applicable portions when moving to the target cell.

[0165] The UE may be configured with an explicit indicator that indicates whether a relevant configuration portion can remain inactive (or can enter a deactivated state) without being released when the associated PCI becomes a non-serving cell, or whether the relevant configuration portion should be released. The UE may be configured with an explicit indicator that indicates whether a relevant configuration portion can remain active at least partially in the case of a role change (via adaptation) when the associated PCI becomes a non-serving cell. The indicator may be configured when the network configures the UE with a configuration portion or when a mobility command is provided.

[0166] Figure 10 An example of configuration parameters of a cell according to an embodiment of the present disclosure is shown.

[0167] Referring to Figure 10 , the UE may be configured with configuration parameters for Cell 1 and Cell 2. The UE may be configured with a non-shared serving cell configuration portion for Cell 1 that is applicable only when Cell 1 is a serving cell, and the UE may also be configured with a non-shared serving cell configuration portion for Cell 2 that is applicable only when Cell 2 is a serving cell, as well as a shared dedicated configuration portion that is applicable to both Cell 1 and Cell 2 (i.e., applicable when Cell 1 is a serving cell and also applicable when Cell 2 is a serving cell).

[0168] The shared dedicated configuration portion may include a shared dedicated configuration library 1 applicable to Cell 1 and a shared dedicated configuration library 2 applicable to Cell 2. The shared dedicated configuration portion may include a shared dedicated configuration library applicable to both Cell 1 and Cell 2. For the shared dedicated configuration portion, an adjustment configuration portion may also be configured. The adjustment configuration portion may include an adjustment configuration for Cell 1 and an adjustment configuration for Cell 2.

[0169] The adjustment configuration for Cell 1 may include adjustment_1s, which is used to adjust the shared dedicated configuration library 1 when Cell 1 is a serving cell. The adjustment configuration for Cell 1 may include adjustment_1n, which is used to adjust the shared dedicated configuration library 1 when Cell 1 is a non-serving cell.

[0170] The adjustment configuration for Cell 2 may include adjustment_2s, which is used to adjust the shared dedicated configuration library 2 when Cell 2 is a serving cell. The adjustment configuration for Cell 2 may include adjustment_2n, which is used to adjust the shared dedicated configuration library 2 when Cell 2 is a non-serving cell.

[0171] For example, the reference configuration for Cell #1 and Cell #2 may include at least one of the shared dedicated configuration library 1 or the shared dedicated configuration library 2.

[0172] The modified configuration for cell #1 may include at least one of the modified configuration of the serving cell related to cell #1 and the modified configuration of the non-serving cell related to cell #1. The modified configuration for the serving cell related to cell #1 may include at least one of common configuration part 1, non-shared dedicated configuration 1, or adjustment_1s. The modified configuration for the non-serving cell related to cell #1 may include adjustment_1n.

[0173] The modified configuration for cell #2 may include at least one of the modified configuration of the serving cell related to cell #2 and the modified configuration of the non-serving cell related to cell #2. The modified configuration for the serving cell related to cell #2 may include at least one of common configuration part 2, non-shared dedicated configuration 2, or adjustment_2s. The modified configuration for the non-serving cell related to cell #2 may include adjustment_2n.

[0174] Figure 11 An example of the configuration parameters for a cell before a serving cell change according to an embodiment of the present disclosure is shown.

[0175] Referring to Figure 11 , cell #1 may be configured as the serving cell of the UE. Cell #2 may be configured as a non-serving cell, for example, a candidate cell that may become a serving cell.

[0176] The UE may activate the non-shared serving cell configuration part of cell 1. The UE may deactivate the non-shared serving cell configuration part of cell 2.

[0177] The UE may use the adjustment to activate the shared dedicated configuration part, where the UE adjusts the shared dedicated configuration library 1 based on adjustment_1s and also adjusts the shared dedicated configuration library 2 based on adjustment_2n. Then, the UE may apply the activated configuration part as the serving cell configuration.

[0178] Figure 12 An example of the configuration parameters of the cell after the serving cell change according to an embodiment of the present disclosure is shown.

[0179] Referring to Figure 12 , due to the mobility or change of the serving cell, cell #2 may become the serving cell.

[0180] The UE may activate the non-shared serving cell configuration part of cell 2. The UE may deactivate the non-shared serving cell configuration part of cell 1.

[0181] The UE may use the adjustment to activate the shared dedicated configuration part, where the UE adjusts the shared dedicated configuration library 1 based on adjustment_1n and also adjusts the shared dedicated configuration library 2 based on adjustment_2s. Then, the UE may apply the activated configuration part as the serving cell configuration.

[0182] Meanwhile, when a cell becomes a serving cell, the cell can be a special cell (SpCell) or a secondary cell (SCell). Therefore, to configure a serving cell, if the serving cell is a special cell, it is sufficient for the network to configure a special cell configuration (SpCellConfig), or if the serving cell is an SCell, it is sufficient for the network to configure an SCell configuration (SCellConfig).

[0183] In conditional mobility, a complete RRC reconfiguration is preconfigured for the UE as a UE / cell group configuration for each candidate cell, where the UE applies the RRC reconfiguration if the candidate cell becomes a special cell. If there are multiple candidate cells to be configured and frequent mobility between candidate cells based on the preconfiguration is required, conditional mobility may result in excessive signaling overhead and large configuration latency.

[0184] To allow for frequent mobility between configured candidate cells while reducing signaling overhead, it is desirable to develop a new mobility method and configuration method.

[0185] In the present disclosure, a common candidate configuration pool is introduced, and different cell group candidates refer to a subset of the content of the common candidate configuration pool according to their needs.

[0186] Specifically, the present disclosure proposes a method that allows the network to control a candidate cell configuration pool during mobility by controlling whether the current (source) cell configuration can be added to the candidate cell configuration pool as a candidate cell configuration during / after mobility.

[0187] In the present disclosure, although the embodiments have been described as being applied to the case of MCG, this is only for illustrative purposes and is equally applicable to the case of SCG.

[0188] Figure 13 An example of a method performed by a UE according to an embodiment of the present disclosure is shown. This method can also be performed by a wireless device.

[0189] Referring to Figure 13 , in step S1301, the UE can receive a list of cell configurations for multiple candidate cells from the network via the source cell.

[0190] In step S1303, the UE can perform mobility from the source cell to a first target cell among the multiple candidate cells based on applying the cell configuration for the first target cell.

[0191] In step S1305, after performing mobility to the first target cell, the UE may determine whether to update the list by storing the cell configuration for the source cell in the list based on the first control information received from the network.

[0192] In step S1307, the UE may perform measurements for subsequent mobility based on the updated list.

[0193] According to various embodiments, based on the first control information notifying to store the cell configuration for the source cell in the list, the UE may store the cell configuration for the source cell in the list. Based on the first control information notifying not to store the cell configuration for the source cell in the list, the UE may maintain the cell configuration list.

[0194] According to various embodiments, the UE may receive from the network the first control information notifying whether to store the cell configuration for the source cell in the list via at least one of the following: downlink control information (DCI), media access control (MAC) control element (CE) signaling, or radio resource control (RRC) signaling.

[0195] According to various embodiments, the first control information may be included in the cell group configuration for a cell group including the first target cell as a special cell (SpCell). The cell group configuration for the first target cell may include at least one of the following: an identifier (ID) of the cell configuration for the first target cell; the SpCell configuration for the first target cell; the ID of the cell configuration for one or more secondary cells (SCells) in the cell group; or the SCell configuration for one or more SCells.

[0196] According to various embodiments, the cell group configuration may be received separately from the cell configuration for the first target cell, or may be included in the cell configuration for the first target cell.

[0197] According to various embodiments, the first control information may include an indicator. The indicator set to a first value may notify to store the cell configuration for the source cell in the list. The indicator set to a second value may notify not to store the cell configuration for the source cell in the list.

[0198] According to various embodiments, the first control information may include a set of cells allowed to store their cell configurations in the list. The first control information may notify to store the cell configuration for the source cell in the list based on the source cell belonging to the set of cells. The first control information may notify not to store the cell configuration for the source cell in the list based on the source cell not belonging to the set of cells.

[0199] According to various embodiments, a UE may obtain measurement results for a plurality of candidate cells based on measuring reference signals related to the plurality of candidate cells. The UE may send a measurement report including the measurement results for the plurality of candidate cells to the network. The UE may receive information from the network notifying a first target cell as a mobility target.

[0200] According to various embodiments, a UE may obtain measurement results for a plurality of candidate cells based on measuring reference signals related to the plurality of candidate cells. The UE may evaluate mobility conditions for each of the plurality of candidate cells based on the measurement results for the plurality of candidate cells. The UE may determine a first target cell among the plurality of candidate cells that satisfies the mobility conditions.

[0201] According to various embodiments, a UE may measure reference signals related to candidate cells whose cell configurations are included in an updated list.

[0202] According to various embodiments, a UE may determine a second target cell among candidate cells based on measuring reference signals related to the candidate cells. The UE may perform subsequent mobility to the second target cell based on applying the cell configuration for the second target cell. After performing the subsequent mobility to the second target cell, the UE may determine whether to update the list by storing the cell configuration for the first target cell in the list based on second control information received from the network.

[0203] According to various embodiments, the second control information may notify whether to store the cell configuration for the first target cell in the list. The second control information may be received i) through at least one of the following: downlink control information (DCI), media access control (MAC) control element (CE) signaling, or radio resource control (RRC) signaling, or ii) included in the cell group configuration for a cell group including the second target cell as a special cell (SpCell).

[0204] Figure 14 An example of a signal flow between a UE and a network node according to an embodiment of the present disclosure is shown. The network node may include a base station (BS).

[0205] Refer to Figure 14 , in step S1401, the network node may send a cell configuration list for a plurality of candidate cells to the UE.

[0206] In step S1403, the network node may send reference signals related to the plurality of candidate cells to the UE.

[0207] In step S1405, the UE may determine a target cell among the plurality of candidate cells based on measuring reference signals related to the plurality of candidate cells.

[0208] In step S1407, the UE may perform mobility from the source cell to the target cell based on the cell configuration of the application for the target cell.

[0209] In step S1409, after performing mobility to the target cell, the UE may determine whether to update the list by storing the cell configuration for the source cell in the list based on the control information received from the network.

[0210] In step S1411, the UE may perform measurements for subsequent mobility based on the updated list.

[0211] Figure 15 An example of a method for post - mobility processing of a source cell configuration according to an embodiment of the present disclosure is shown. The method may be performed by a UE and / or a wireless device.

[0212] Refer to Figure 15 , in step S1501, the UE may apply an active cell group configuration for an active cell group including a SpCell and optionally one or more SCell. The UE may be configured with the active cell group configuration and apply the active cell group configuration. The serving cell may be configured within the active cell group configuration. For example, the active cell group configuration may include a SpCell configuration (i.e., SpCellConfig) for the SpCell and optionally one or more SCell configurations (i.e., SCellConfig) for one or more SCell.

[0213] In step S1503, the UE may receive one or more cell group configurations (i.e., CandidateCellGroupConfig) for one or more candidate cell groups. Exemplary information elements (IEs) included in the cell group configuration are shown in Table 5:

[0214] [Table 5]

[0215]

[0216]

[0217] The UE may be configured with one or more candidate cell groups. Each candidate cell group may include a candidate SpCell and zero or more candidate SCell, and the configuration for each cell group corresponding to the candidate cell group may include the configuration of the SpCell (i.e., SpCellConfig) and zero or more configurations of the SCell (i.e., sCellsToRemovelist / sCellsToAddModList). The configuration of the SpCell may include a configuration ID (i.e., configID) and / or an explicit SpCell configuration for the SpCell (i.e., explicitSpCellConfig). The configuration ID may refer to the SpCell configuration (i.e., candSpCellConfig) in the cell configuration (i.e., CandCellConfig) that includes the corresponding configuration ID (i.e., candidateCellConfigID) in the candidate cell configuration pool (i.e., CandidateCellPoolConfig).

[0218] For example, the explicit SpCell configuration may be configured / applied as a complete configuration. In order for the UE to apply the complete configuration of the SpCell, an indicator of the complete configuration of the SpCell may be included in the configuration of the SpCell. Also, for example, the explicit SpCell configuration may be configured / applied as an incremental configuration. In order for the UE to apply the incremental configuration of the SpCell, an indicator of the incremental configuration of the SpCell may be included in the configuration of the SpCell.

[0219] The configuration of zero or more SCell may include the configuration of adding / modifying zero or more SCell (i.e., sCellsToAddModList), and / or the configuration of removing zero or more SCell (i.e., sCellsToRemoveList).

[0220] The configuration of adding / modifying zero or more SCell may include a list of configurations of the SCell to be added / modified. Each configuration of the SCell may include a configuration ID (i.e., configID) and / or an explicit SCell configuration for the SCell (i.e., explicitSCellConfig). The configuration ID may refer to the SCell configuration (i.e., candSCellConfig) in the cell configuration (i.e., CandCellConfig) that includes the corresponding configuration ID (i.e., candidateCellConfigID) in the candidate cell configuration pool (i.e., CandidateCellPoolConfig).

[0221] For example, an explicit SCell configuration can be configured / applied as a complete configuration. To enable the UE to apply the complete configuration of the SCell, an SCell complete configuration indicator can be included in the configuration of the SCell. Also, for example, an explicit SCell configuration can be configured / applied as an incremental configuration. To enable the UE to apply the incremental configuration of the SCell, an SCell incremental configuration indicator can be included in the configuration of the SCell.

[0222] Removing the configuration of zero or more SCell(s) can include an indicator (i.e., allSCellsToRemove) indicating whether to remove all SCell(s) in the current active cell group, and / or a list of serving cell IDs associated with the SCell(s) to be removed.

[0223] Each cell group configuration of a candidate cell group can include control information for controlling a candidate cell configuration pool during mobility (i.e., addServingCellAsCandidateCell). For example, the control information can be a simple allow / deny type indicator. This is to enable per-target-cell control granularity. Also, for example, the control information can include a cell list (i.e., source cell list / allowedSourceCellList). This is to enable per-source-cell-target-cell pair control granularity.

[0224] Each cell group configuration of a candidate cell group can include cell status information (i.e., allowedCandidateCellList) indicating which candidate cells in the candidate cell group / candidate cell configuration pool are active or inactive. For example, the cell status information can include an "allCandCellsToAllow" field indicating that all candidate cells in the candidate cell group / candidate cell configuration pool are active, or a "candCellsToAllow" field indicating that one or more cell configuration IDs in the candidate cell group / candidate cell configuration pool are active.

[0225] In some implementations, the cell status information may not be included in the cell group configuration, but may be received from the network via separate signaling.

[0226] In step S1505, the UE can receive a candidate cell configuration pool (i.e., CandidateCellPoolConfig). Exemplary IEs included in the candidate cell configuration pool are shown in Table 6:

[0227] [Table 6]

[0228]

[0229] The UE can be configured with a candidate cell configuration pool. The candidate cell configuration pool can include a set of cell configurations for a set of candidate cells, where each cell configuration is associated with a corresponding candidate cell in the set of candidate cells. The cell configuration (i.e., CandCellConfig) for each candidate cell in the candidate cell configuration pool can include a configuration ID (i.e., candidateCellConfigID), a SpCell configuration (i.e., candSpCellConfig), an SCell configuration (i.e., candSCellConfig), and / or status information. The SpCell configuration can be applied when the candidate cell is configured as a SpCell, and can include the cell ID of the SpCell and the corresponding configuration (e.g., sPCellConfig). The SCell configuration can be applied when the candidate cell is configured as an SCell, and can include the cell ID of the SCell and the corresponding configuration (e.g., SCellConfig). The status information can be determined / informed by the cell status information included in the cell group configuration or received from the network.

[0230] In some implementations, the cell configuration of a candidate cell and / or the SpCell configuration in the cell configuration can include the cell group configuration of the candidate cell (i.e., the cell group configuration of the candidate cell group that includes the candidate cell as a SpCell).

[0231] In step S1507, when moving to a candidate cell or when initiating mobility to a candidate cell, the UE can select the cell group configuration of the candidate cell (i.e., the cell group configuration of the candidate cell group that includes the candidate cell as a SpCell) as the active cell group configuration.

[0232] In the case of handover to a candidate cell / mobility to a candidate cell, the UE can select the cell group configuration that includes the candidate cell as a SpCell, and regard the selected cell group configuration and the candidate cell group as the active cell group configuration and the active cell group, respectively. Other cell group configurations may not be regarded as the active cell group configuration. For each serving cell of the active cell group configuration, the UE can determine the configuration of each serving cell.

[0233] For the SpCell of the active cell group, if the SpCell configuration of the SpCell is derived from the candidate cell configuration pool, the UE can apply the SpCell configuration within the cell configuration of the SpCell as the configuration of the SpCell in the active cell group. If the SpCell configuration of the SpCell is based on a complete / incremental configuration, the UE can apply the complete / incremental configuration of the SpCell configured by the active cell group configuration (i.e., explicitSpCellConfig).

[0234] For the SCell of the active cell group, if the SCell configuration of the SCell is obtained from the candidate cell configuration pool, the UE may apply the SCell configuration in the cell configuration of the SCell as the configuration of the SCell in the active cell group. If the SCell configuration of the SCell is based on a complete / incremental configuration, the UE may apply the complete / incremental configuration of the SCell configured by the active cell group configuration (i.e., explicitSCellConfig).

[0235] In step S1509, the UE may adjust the candidate cell configuration pool based on the control information that controls the candidate cell configuration pool. The UE may adjust the candidate cell configuration pool in the following ways:

[0236] 1) When the control information that controls the candidate cell configuration pool (i.e., addServingCellAsCandidateCell) is of the allow / disallow type:

[0237] - If the control information indicates "allow / true", the UE may add the source cell configuration to the candidate cell configuration pool;

[0238] - If the control information indicates "disallow / false", the UE will not add the source cell configuration to the candidate cell configuration pool.

[0239] 2) When the control information that controls the candidate cell configuration pool includes cell ID list information (i.e., allowedSourceCellList):

[0240] - If the source cell is included in the cell ID list information, the UE may add the source cell configuration to the candidate cell configuration pool;

[0241] - If the source cell is not included in the cell ID list information, the UE will not add the source cell configuration to the candidate cell configuration pool.

[0242] For example, the UE may be configured with an MCG including a PCell and an SCell, as shown in Table 7:

[0243] [Table 7]

[0244]

[0245] In addition, the UE may be configured with three candidate cell groups, as shown in Table 8:

[0246] [Table 8]

[0247]

[0248]

[0249] In addition, the UE can be configured with a candidate cell configuration pool, as shown in Table 9:

[0250] [Table 9]

[0251]

[0252] Then, according to the present disclosure, during mobility, the UE can apply the following CG configuration as the active CG configuration: Case 1) When moving (or initiating the movement) to a candidate cell corresponding to candCellConfig[1], the UE can select candidateCellGroupConfig[1] as the active CG configuration and apply the serving cell configurations of the CG for special cells and SCell based on candidateCellGroupConfig[1], as shown in Table 10:

[0253] [Table 10]

[0254]

[0255] That is, according to candidateCellGroupConfig[1], since sPCellConfig includes a configID set to 1, the UE shall apply candSpCellconfig[1] in candCellConfig[1] with candidateCellConfigID set to 1. In addition, according to candidateCellGroupConfig[1], since sCellsToAddModList includes a configID set to 2 and a configID set to 3, the UE shall add / apply candSCellconfig[2] within candCellConfig[2] with candidateCellConfigID set to 2, and add / apply candSCellconfig[3] within candCellConfig[3] with candidateCellConfigID set to 3. The allowedCandidateCellList field in candSpCellconfig[1] includes candCellsToAllow (i.e., cell status information) indicating a configID set to 2. Therefore, after mobility to the candidate cell corresponding to candCellConfig[1], candCellConfig[2] may be active while candCellConfig[3] may be inactive. candCellConfig[1] may be inactive because it is the current serving cell after mobility to the candidate cell corresponding to candCellConfig[1].

[0256] In addition, according to candidateCellGroupConfig[1], since addServingCellAsCandidateCell is set to "true", the source cell may be added to the candidate cell configuration pool. There may be two ways to add the source cell to the candidate cell configuration pool (Alternative 1 and Alternative 2).

[0257] According to Case 1, the active cell group configuration after mobility to the candidate cell corresponding to candCellConfig[1] is shown in Table 11:

[0258] [Table 11]

[0259]

[0260] Scenario 2) When moving to (or initiating the mobility towards) the candidate cell corresponding to candCellConfig[2], the UE may select candidateCellGroupConfig[2] as the active CG configuration and apply the serving cell configurations for the SpCell and SCell of the CG based on candidateCellGroupConfig[2], as shown in Table 12:

[0261] [Table 12]

[0262]

[0263] That is, according to candidateCellGroupConfig[2], since sPCellConfig includes explicitSpCellConfig, the UE shall apply the SpCellconfig indicated by explicitSpCellConfig in candidateCellGroupConfig[2]. In addition, according to candidateCellGroupConfig[2], since sCellsToRemoveList includes sCellsToRemove, which notifies SERVING_CELL_ID_2 and SERVING_CELL_ID_3, the UE may remove SCellConfig[a] and SCellConfig[b] related to SERVING_CELL_ID_2 and SERVING_CELL_ID_3, respectively. sCellsToAddModList includes explicitSCellConfig[1] of SERVING_CELL_ID_4 related to the configured SCellConfig[c], and explicitSCellConfig[2] of the newly configured SERVING_CELL_ID_6. Therefore, the UE may apply explicitSCellConfig[1] as an incremental configuration to SCellConfig[c] (i.e., modify it), and add / apply the SCellConfig indicated by explicitSCellConfig[2] in candidateCellGroupConfig[2].

[0264] The allowedCandidateCellList field in candSpCellconfig[2] includes candCellsToAllow (i.e., cell status information), which indicates allCandCellsToAllow. Therefore, after mobility to the candidate cell corresponding to candCellConfig[2], candCellConfig[1] and candCellConfig[3] may be active. candCellConfig[2] may be inactive because it is the current serving cell after mobility to the candidate cell corresponding to candCellConfig[2].

[0265] In addition, according to candidateCellGroupConfig[2], since addServingCellAsCandidateCell is set to "true", the source cell may be added to the candidate cell configuration pool. There may be two ways (Alternative 1 and Alternative 2) to add the source cell to the candidate cell configuration pool.

[0266] According to Case 2, the active cell group configuration after mobility to the candidate cell corresponding to candCellConfig[2] is shown in Table 13:

[0267] [Table 13]

[0268]

[0269]

[0270] Case 3) When the UE makes a mobility (or initiates a mobility) to the candidate cell corresponding to candCellConfig[3], the UE can select candidateCellGroupConfig[3] as the active CG configuration and apply the serving cell configurations for the SpCell and SCell of the CG based on candidateCellGroupConfig[3], as shown in Table 14:

[0271] [Table 14]

[0272]

[0273] That is, according to candidateCellGroupConfig[3], since the sPCellConfig includes a configID set to 3, the UE shall apply candSpCellconfig[3] in candCellConfig[3] that includes a candidateCellConfigID set to 3. In addition, according to candidateCellGroupConfig[3], since the sCellsToAddModList includes a configID set to 1 and an explicitSCellConfig for the newly configured SERVING_CELL_ID_6, the UE shall add / apply candSCellconfig[1] in candCellConfig[1] that includes a candidateCellConfigID set to 1, and add / apply the SCellConfig indicated by the explicitSCellConfig in candidateCellGroupConfig[3]. The allowedCandidateCellList field in candSpCellconfig[3] includes candCellsToAllow (i.e., cell status information), which indicates allCandCellsToAllow. Therefore, after mobility to the candidate cell corresponding to candCellConfig[3], candCellConfig[1] and candCellConfig[2] may be active. candCellConfig[3] may be inactive because it is the current serving cell after mobility to the candidate cell corresponding to candCellConfig[3].

[0274] In addition, according to candidateCellGroupConfig[3], since addServingCellAsCandidateCell is set to "false", the source cell may not be added to the candidate cell configuration pool.

[0275] According to Case 3, the active cell group configuration after mobility to the candidate cell corresponding to candCellConfig[3] is shown in Table 15:

[0276] [Table 15]

[0277]

[0278]

[0279] In addition, the methods described from the UE perspective in this disclosure (e.g., in Figure 13 ) can be performed byFigure 2 the first wireless device 100 shown in and / or Figure 3 the UE 100 shown in performs. More specifically, the UE includes at least one transceiver, at least one processor, and at least one computer memory that is operably connected to the at least one processor and stores instructions that perform operations when executed by the at least one processor.

[0280] The operations include: receiving, via a source cell, a list of cell configurations for a plurality of candidate cells from a network; performing mobility from the source cell to a first target cell among the plurality of candidate cells based on applying the cell configuration for the first target cell; after performing the mobility to the first target cell, determining whether to update the list by storing the cell configuration for the source cell in the list based on first control information received from the network; and performing measurements for subsequent mobility based on the updated list.

[0281] In addition, the methods described in this disclosure from the perspective of the UE (e.g., in Figure 13 ) can be executed by software code 105 stored in the memory 104 included in the first wireless device 100 shown in Figure 2 .

[0282] More specifically, at least one computer-readable medium (CRM) stores instructions that perform operations when executed by at least one processor, and the operations include: receiving, via a source cell, a list of cell configurations for a plurality of candidate cells from a network; performing mobility from the source cell to a first target cell among the plurality of candidate cells based on applying the cell configuration for the first target cell; after performing the mobility to the first target cell, determining whether to update the list by storing the cell configuration for the source cell in the list based on first control information received from the network; and performing measurements for subsequent mobility based on the updated list.

[0283] In addition, the methods described in this disclosure from the perspective of the UE (e.g., in Figure 13 ) can be executed under the control of the processor 102 included in the first wireless device 100 shown in Figure 2 and / or under the control of the processor 102 included in the UE 100 shown in Figure 3 .

[0284] More specifically, an apparatus (e.g., wireless device / UE) configured / adapted to operate in a wireless communication system includes at least one processor and at least one computer memory capable of being operatively connected to the at least one processor. The at least one processor is configured / adapted to perform operations, including: receiving a list of cell configurations for multiple candidate cells from a network via a source cell; performing mobility from the source cell to a first target cell among the multiple candidate cells based on applying the cell configuration for the first target cell; after performing mobility to the first target cell, determining whether to update the list by storing the cell configuration for the source cell in the list based on first control information received from the network; and performing measurements for subsequent mobility based on the updated list.

[0285] In addition, the method described in the present disclosure from the perspective of the network node (for example, in Figure 14 (in Chinese) can be Figure 2 The second wireless device 200 is shown to perform.

[0286] More specifically, the network node includes at least one transceiver, at least one processor, and at least one computer memory operatively connected to the at least one processor and storing instructions that perform operations upon execution by the at least one processor.

[0287] The operations include: sending a cell configuration list for multiple candidate cells to a user equipment (UE); and sending a reference signal related to the multiple candidate cells to the UE for mobility to a target cell among the multiple candidate cells, wherein the UE is configured to: perform mobility from a source cell to a target cell based on applying the cell configuration for the target cell; after performing mobility to the target cell, determine whether to update the list by storing the cell configuration for the source cell in the list based on control information received from the network; and perform measurements for subsequent mobility based on the updated list.

[0288] The present disclosure may have various beneficial effects.

[0289] For example, the UE may selectively switch the serving cell configuration to the candidate cell configuration after mobility, thereby preventing inappropriate fallback to the serving cell configuration after mobility.

[0290] The beneficial effects that can be obtained by the specific embodiments of the present disclosure are not limited to the beneficial effects listed above. For example, there may be various technical effects that can be understood by a person skilled in the relevant art and / or derived from the present disclosure. Therefore, the specific effects of the present disclosure are not limited to those explicitly described herein, but may include various effects that can be understood or derived from the technical features of the present disclosure.

[0291] The claims in the present disclosure can be combined in various ways. For example, the technical features in the method claims of the present disclosure can be combined to be implemented or executed in a device, and the technical features in the device claims can be combined to be implemented or executed in a method. In addition, the technical features in the method claims and the device claims can be combined to be implemented or executed in a device. In addition, the technical features in the method claims and the device claims can be combined to be implemented or executed in a method. Other implementations are within the scope of the appended claims.

Claims

1. A method performed by a user equipment (UE) in a wireless communication system, the method comprising the steps of: receiving, from a network via a source cell, a list of cell configurations for a plurality of candidate cells; performing mobility from the source cell to a first target cell among the plurality of candidate cells based on applying the cell configuration for the first target cell; after performing the mobility to the first target cell, determining whether to update the list by storing the cell configuration for the source cell in the list based on first control information received from the network; and performing measurements for subsequent mobility based on the updated list.

2. The method according to claim 1, the method further comprising the steps of: notifying, based on the first control information, to store the cell configuration for the source cell in the list, and storing the cell configuration for the source cell in the list; and notifying, based on the first control information, not to store the cell configuration for the source cell in the list, and maintaining the list of cell configurations.

3. The method according to claim 1, the method further comprising: receiving, from the network via at least one of the following, the first control information notifying whether to store the cell configuration for the source cell in the list: downlink control information (DCI), media access control (MAC) control element (CE) signaling, or radio resource control (RRC) signaling.

4. The method according to claim 1, wherein the first control information is included in a cell group configuration for a cell group including the first target cell as a special cell (SpCell), wherein the cell group configuration for the first target cell includes at least one of the following: an identifier (ID) of the cell configuration for the first target cell; the SpCell configuration for the first target cell; the ID of the cell configuration for one or more secondary cells (SCells) in the cell group; or the SCell configuration for the one or more SCells.

5. The method according to claim 4, wherein the cell group configuration is received separately from the cell configuration for the first target cell, or is included in the cell configuration for the first target cell.

6. The method according to claim 1, wherein the first control information includes an indicator, wherein the indicator set to a first value notifies to store the cell configuration for the source cell in the list, and wherein the indicator set to a second value notifies not to store the cell configuration for the source cell in the list.

7. The method according to claim 1, wherein the first control information includes a set of cells allowing cell configurations to be stored in the list, wherein the first control information notifies to store the cell configuration for the source cell in the list based on the source cell belonging to the set of cells, and Wherein, the first control information notifies not to store the cell configuration for the source cell in the list based on the source cell not belonging to the set of cells.

8. The method according to claim 1, the method further comprises the following steps: obtaining measurement results for the plurality of candidate cells based on measuring reference signals related to the plurality of candidate cells; sending a measurement report including the measurement results for the plurality of candidate cells to the network; and receiving, from the network, information notifying the first target cell as a mobility target.

9. The method according to claim 1, the method further comprises the following steps: obtaining measurement results for the plurality of candidate cells based on measuring reference signals related to the plurality of candidate cells; evaluating mobility conditions for each of the plurality of candidate cells based on the measurement results for the plurality of candidate cells; and determining the first target cell among the plurality of candidate cells that satisfies the mobility conditions.

10. The method according to claim 1, wherein the step of performing the measurement for the subsequent mobility based on the updated list comprises: measuring reference signals related to candidate cells whose cell configurations are included in the updated list.

11. The method according to claim 10, the method further comprises the following steps: determining a second target cell among the candidate cells based on measuring the reference signals related to the candidate cells; and performing the subsequent mobility to the second target cell based on applying the cell configuration for the second target cell; after performing the subsequent mobility to the second target cell, determining whether to update the list by storing the cell configuration for the first target cell in the list based on second control information received from the network.

12. The method according to claim 11, wherein the second control information notifies whether to store the cell configuration for the first target cell in the list, and wherein the second control information is received i) by at least one of the following: downlink control information DCI, media access control MAC control element CE signaling, or radio resource control RRC signaling, or ii) is included in the cell group configuration for a cell group including the second target cell as a special cell SpCell.

13. The method according to claims 1 to 12, wherein the UE communicates with at least one of a mobile device, a network, or an autonomous vehicle.

14. A user equipment UE configured to operate in a wireless communication system, the UE comprises: at least one transceiver; at least one processor; and at least one memory, the at least one memory being operatively coupled to the at least one processor and storing instructions that, when executed by the at least one processor, perform operations, the operations including: receiving, from a network via a source cell, a list of cell configurations for a plurality of candidate cells; Perform mobility from the source cell to the first target cell among the multiple candidate cells based on the cell configuration of the application for the first target cell; After performing the mobility to the first target cell, determine whether to update the list by storing the cell configuration for the source cell in the list based on the first control information received from the network; and Perform measurements for subsequent mobility based on the updated list.

15. The UE according to claim 14, wherein, The UE is arranged to implement the method according to one of claims 2 to 13.

16. A network node configured to operate in a wireless communication system, the network node comprises: At least one transceiver; At least one processor; and At least one memory, the at least one memory is operatively coupled to the at least one processor and stores instructions, the instructions perform operations based on being executed by the at least one processor, the operations include: Send a list of cell configurations for multiple candidate cells to a user equipment UE; and Send a reference signal related to the multiple candidate cells to the UE for mobility to a target cell among the multiple candidate cells, wherein, the UE is configured to: Perform mobility from a source cell to the target cell based on applying the cell configuration for the target cell; After performing the mobility to the target cell, determine whether to update the list by storing the cell configuration for the source cell in the list based on the control information received from the network; and Perform measurements for subsequent mobility based on the updated list.

17. A method performed by a network node configured to operate in a wireless communication system, the method comprises: Send a list of cell configurations for multiple candidate cells to a user equipment UE; and Send a reference signal related to the multiple candidate cells to the UE for mobility to a target cell among the multiple candidate cells, wherein, the UE is configured to: Perform mobility from a source cell to the target cell based on applying the cell configuration for the target cell; After performing the mobility to the target cell, determine whether to update the list by storing the cell configuration for the source cell in the list based on the control information received from the network; and Perform measurements for subsequent mobility based on the updated list.

18. The method according to claim 17, wherein, The UE is arranged to implement the method according to one of claims 1 to 13.

19. A device adapted to operate in a wireless communication system, the device comprises: At least one processor; and At least one memory, the at least one memory is operatively coupled to the at least one processor and stores instructions, the instructions perform operations based on being executed by the at least one processor, the operations include: Receive a list of cell configurations for multiple candidate cells from a network via a source cell; Perform mobility from the source cell to the first target cell among the multiple candidate cells based on the cell configuration for the first target cell applied by the application; After performing the mobility to the first target cell, determine whether to update the list by storing the cell configuration for the source cell in the list based on the first control information received from the network; and Perform measurements for subsequent mobility based on the updated list.

20. A non-transitory computer-readable medium CRM, on which program code is stored, the program code implementing instructions that, when executed by at least one processor, perform operations, the operations include: Receive, via a source cell, a list of cell configurations for multiple candidate cells from a network; Perform mobility from the source cell to the first target cell among the multiple candidate cells based on the cell configuration for the first target cell applied by the application; After performing the mobility to the first target cell, determine whether to update the list by storing the cell configuration for the source cell in the list based on the first control information received from the network; and Perform measurements for subsequent mobility based on the updated list.

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