Failure information reporting in conditional mobility

Abstract

The present disclosure is related to failure information reporting in conditional mobility in wireless communications. According to an embodiment of the present disclosure, a method performed by a user equipment (UE) comprises: receiving a conditional reconfiguration comprising execution conditions including: one or more execution conditions for conditional handover (CHO) for a candidate primary cell (PCell); and one or more execution conditions for primary secondary cell (PSCell) mobility for a candidate PSCell related to the candidate PCell; evaluating the one or more execution conditions for CHO and the one or more execution conditions for PSCell mobility; based on detecting a failure related to a master cell group (MCG), transmitting a radio link failure (RLF) report comprising one or more first evaluation results among evaluation results of the execution conditions; and based on detecting a failure related to a secondary cell group (SCG), transmitting SCG failure information comprising one or more second evaluation results among the evaluation results of the execution conditions.

Description

FAILURE INFORMATION REPORTING IN CONDITIONAL MOBILITY

[0001] The present disclosure is related to failure information reporting in conditional mobility in wireless communications.

[0002] 3rd Generation Partnership Project (3GPP) Long-Term Evolution (LTE) is a technology for enabling high-speed packet communications. Many schemes have been proposed for the LTE objective including those that aim to reduce user and provider costs, improve service quality, and expand and improve coverage and system capacity. The 3GPP LTE requires reduced cost per bit, increased service availability, flexible use of a frequency band, a simple structure, an open interface, and adequate power consumption of a terminal as an upper-level requirement.

[0003] Work has started in International Telecommunication Union (ITU) and 3GPP to develop requirements and specifications for New Radio (NR) systems. 3GPP has to identify and develop the technology components needed for successfully standardizing the new RAT timely satisfying both the urgent market needs, and the more long-term requirements set forth by the ITU Radio communication sector (ITU-R) International Mobile Telecommunications (IMT)-2020 process. Further, the NR should be able to use any spectrum band ranging at least up to 100 GHz that may be made available for wireless communications even in a more distant future.

[0004] The NR targets a single technical framework addressing all usage scenarios, requirements and deployment scenarios including enhanced Mobile BroadBand (eMBB), massive Machine Type Communications (mMTC), Ultra-Reliable and Low Latency Communications (URLLC), etc. The NR shall be inherently forward compatible.

[0005] In communication systems, UE may detect various types of failures. For example, UE may detect a radio link failure (RLF)　when the radio link quality remains below a threshold for a set duration (e.g.,　T310　expiry) or when random access fails. For example, the UE may detect a mobility failure (e.g., handover failure) if the UE fails to complete a handover to a target cell within a specific time (e.g.,　T304　expiry). When a failure is detected, the UE may log　failure-related information (e.g., measurements, failure cause, and location), and transmit the failure-related information to network.

[0006] An aspect of the present disclosure is to provide method and apparatus for failure information reporting in conditional mobility in a wireless communication system.

[0007] According to an embodiment of the present disclosure, a method performed by a user equipment (UE) comprises: receiving a conditional reconfiguration comprising execution conditions including: one or more execution conditions for conditional handover (CHO) for a candidate primary cell (PCell); and one or more execution conditions for primary secondary cell (PSCell) mobility for a candidate PSCell related to the candidate PCell; evaluating the one or more execution conditions for CHO and the one or more execution conditions for PSCell mobility; based on detecting a failure related to a master cell group (MCG), transmitting a radio link failure (RLF) report comprising one or more first evaluation results among evaluation results of the execution conditions; and based on detecting a failure related to a secondary cell group (SCG), transmitting SCG failure information comprising one or more second evaluation results among the evaluation results of the execution conditions.

[0008] According to an embodiment of the present disclosure, a method performed by a network node comprises: transmitting, to a user equipment (UE), a conditional reconfiguration comprising execution conditions including: one or more execution conditions for conditional handover (CHO) for a candidate primary cell (PCell); and one or more execution conditions for primary secondary cell (PSCell) mobility for a candidate PSCell related to the candidate PCell; receiving, from the UE, a radio link failure (RLF) report comprising one or more first evaluation results among evaluation results of the execution conditions, based on an occurrence of a failure related to a master cell group (MCG); and receiving, from the UE, SCG failure information comprising one or more second evaluation results among the evaluation results of the execution conditions, based on an occurrence of a failure related to a secondary cell group (SCG).

[0009] According to various embodiments, apparatuses to implement the above methods are provided.

[0010] The present disclosure may have various advantageous effects.

[0011] For example, the UE can prevent redundant reporting of the same evaluation results across different reports. Thus, the network can correctly sample and adjust the CHO and the associated CPAC configuration without misinterpretation. Therefore, it can　reduce the risk of　incorrect handover timing,　prevent　unnecessary RLFs, and　optimize　power consumption.

[0012] Advantageous effects which can be obtained through specific embodiments of the present disclosure are not limited to the advantageous effects listed above. For example, there may be a variety of technical effects that a person having ordinary skill in the related art can understand and / or derive from the present disclosure. Accordingly, the specific effects of the present disclosure are not limited to those explicitly described herein, but may include various effects that may be understood or derived from the technical features of the present disclosure.

[0013] FIG. 1 shows an example of a communication system to which implementations of the present disclosure is applied.

[0014] FIG. 2 shows an example of wireless devices to which implementations of the present disclosure is applied.

[0015] FIG. 3 shows an example of UE to which implementations of the present disclosure is applied.

[0016] FIGs. 4 and 5 show an example of protocol stacks in a 3GPP based wireless communication system to which implementations of the present disclosure is applied.

[0017] FIG. 6 shows a frame structure in a 3GPP based wireless communication system to which implementations of the present disclosure is applied.

[0018] FIG. 7 shows a data flow example in the 3GPP NR system to which implementations of the present disclosure is applied.

[0019] FIG. 8 shows an example of a conditional mobility procedure according to an embodiment of the present disclosure.

[0020] FIG. 9 shows an example of an RLF report procedure.

[0021] FIG. 10 shows an example of SCG failure information procedure.

[0022] FIG. 11 shows an example of a method performed by a UE for failure information reporting in conditional mobility according to various embodiments of the present disclosure.

[0023] FIG. 12 shows an example of a signal flow between UE and network node for failure information reporting in conditional mobility according to various embodiments of the present disclosure.

[0024] The following techniques, apparatuses, and systems may be applied to a variety of wireless multiple access systems. Examples of the multiple access systems include a Code Division Multiple Access (CDMA) system, a Frequency Division Multiple Access (FDMA) system, a Time Division Multiple Access (TDMA) system, an Orthogonal Frequency Division Multiple Access (OFDMA) system, a Single Carrier Frequency Division Multiple Access (SC-FDMA) system, and a Multi Carrier Frequency Division Multiple Access (MC-FDMA) system. CDMA may be embodied through radio technology such as Universal Terrestrial Radio Access (UTRA) or CDMA2000. TDMA may be embodied through radio technology such as Global System for Mobile communications (GSM), General Packet Radio Service (GPRS), or Enhanced Data rates for GSM Evolution (EDGE). OFDMA may be embodied through radio technology 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 a part of a Universal Mobile Telecommunications System (UMTS). 3rd Generation Partnership Project (3GPP) Long-Term Evolution (LTE) is a part of Evolved UMTS (E-UMTS) using E-UTRA. 3GPP LTE employs OFDMA in downlink (DL) and SC-FDMA in uplink (UL). Evolution of 3GPP LTE includes LTE-Advanced (LTE-A), LTE-A Pro, and / or 5G New Radio (NR).

[0025] For convenience of description, implementations of the present disclosure are mainly described in regards to a 3GPP based wireless communication system. 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 system are applicable to other mobile communication systems.

[0026] For terms and technologies which are not specifically described among the terms of and technologies employed in the present disclosure, the wireless communication standard documents published before the present disclosure may be referenced.

[0027] In the present disclosure, "A or B" may mean "only A", "only B", or "both A and B". In other words, "A or B" in the present disclosure may be interpreted as "A and / or B". For example, "A, B or C" in the present disclosure may mean "only A", "only B", "only C", or "any combination of A, B and C".

[0028] In the present disclosure, slash ( / ) or comma (,) may mean "and / or". For example, "A / B" may mean "A and / or B". Accordingly, "A / B" may mean "only A", "only B", or "both A and B". For example, "A, B, C" may mean "A, B or C".

[0029] In the present disclosure, "at least one of A and B" may mean "only A", "only B" or "both A and B". In addition, the expression "at least one of A or B" or "at least one of A and / or B" in the present disclosure may be interpreted as same as "at least one of A and B".

[0030] In addition, 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". In addition, "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".

[0031] Also, parentheses used in the present disclosure may mean "for example". In detail, when it is shown as "control information (PDCCH)", "PDCCH" may be proposed as an example of "control information". In other words, "control information" in the present disclosure is not limited to "PDCCH", and "PDCCH" may be proposed as an example of "control information". In addition, even when shown as "control information (i.e., PDCCH)", "PDCCH" may be proposed as an example of "control information".

[0032] Technical features that are separately described in one drawing in the present disclosure may be implemented separately or simultaneously.

[0033] Although not limited thereto, various descriptions, functions, procedures, suggestions, methods and / or operational flowcharts of the present disclosure disclosed herein can be applied to various fields requiring wireless communication and / or connection (e.g., 5G) between devices.

[0034] Hereinafter, the present disclosure will be described in more detail with reference to drawings. 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 unless otherwise indicated.

[0035] FIG. 1 shows an example of a communication system to which implementations of the present disclosure is applied.

[0036] The 5G usage scenarios shown in FIG. 1 are only exemplary, and the technical features of the present disclosure can be applied to other 5G usage scenarios which are not shown in FIG. 1.

[0037] Three main requirement categories for 5G include (1) a category of enhanced Mobile BroadBand (eMBB), (2) a category of massive Machine Type Communication (mMTC), and (3) a category of Ultra-Reliable and Low Latency Communications (URLLC).

[0038] Referring to FIG. 1, the communication system 1 includes wireless devices 100a to 100f, Base Stations (BSs) 200, and a network 300. Although FIG. 1 illustrates a 5G network as an example of the network of the communication system 1, the implementations of the present disclosure are not limited to the 5G system, and can be applied to the future communication system beyond the 5G system.

[0039] The BSs 200 and the network 300 may be implemented as wireless devices and a specific wireless device may operate as a BS / network node with respect to other wireless devices.

[0040] The wireless devices 100a to 100f represent devices performing communication using Radio Access Technology (RAT) (e.g., 5G NR or LTE) and may be referred to as communication / radio / 5G devices. The wireless devices 100a to 100f may include, without being limited to, a robot 100a, vehicles 100b-1 and 100b-2, an eXtended Reality (XR) device 100c, a hand-held device 100d, a home appliance 100e, an Internet-of-Things (IoT) device 100f, and an Artificial Intelligence (AI) device / server 400. For example, the vehicles may include a vehicle having a wireless communication function, an autonomous driving vehicle, and a vehicle capable of performing communication between vehicles. The vehicles may include an Unmanned Aerial Vehicle (UAV) (e.g., a drone). The XR device may include an Augmented Reality (AR) / Virtual Reality (VR) / Mixed Reality (MR) device and may be implemented in the form of a Head-Mounted Device (HMD), a Head-Up Display (HUD) mounted in a vehicle, a television, a smartphone, a computer, a wearable device, a home appliance device, a digital signage, a vehicle, a robot, etc. The hand-held device may include a smartphone, a smartpad, a wearable device (e.g., a smartwatch or a smartglasses), and a computer (e.g., a notebook). The home appliance may include a TV, a refrigerator, and a washing machine. The IoT device may include a sensor and a smartmeter.

[0041] In the present disclosure, the wireless devices 100a to 100f may be called User Equipments (UEs). A UE may include, for example, a cellular phone, a smartphone, a laptop computer, a digital broadcast terminal, a Personal Digital Assistant (PDA), a Portable Multimedia Player (PMP), a navigation system, a slate Personal Computer (PC), a tablet PC, an ultrabook, a vehicle, a vehicle having an autonomous traveling function, a connected car, an 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 a 5G service, or a device related to a fourth industrial revolution field.

[0042] The wireless devices 100a to 100f may be connected to the network 300 via the BSs 200. An 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 beyond-5G network. Although the wireless devices 100a to 100f may communicate with each other through the BSs 200 / network 300, the wireless devices 100a to 100f may perform direct communication (e.g., sidelink communication) with each other without passing through the BSs 200 / 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 device (e.g., a sensor) may perform direct communication with other IoT devices (e.g., sensors) or other wireless devices 100a to 100f.

[0043] Wireless communication / connections 150a, 150b and 150c may be established between the wireless devices 100a to 100f and / or between wireless device 100a to 100f and BS 200 and / or between BSs 200. Herein, the wireless communication / connections may be established through 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)), etc. The wireless devices 100a to 100f and the BSs 200 / the wireless devices 100a to 100f may transmit / receive radio signals to / from each other through the wireless communication / connections 150a, 150b and 150c. For example, the wireless communication / connections 150a, 150b and 150c may transmit / receive signals through various physical channels. To this end, at least a part of various configuration information configuring processes, various signal processing processes (e.g., channel encoding / decoding, modulation / demodulation, and resource mapping / de-mapping), and resource allocating processes, for transmitting / receiving radio signals, may be performed based on the various proposals of the present disclosure.

[0044] NR supports multiples numerologies (and / or multiple Sub-Carrier Spacings (SCS)) to support various 5G services. For example, if SCS is 15 kHz, wide area can be supported in traditional cellular bands, and if SCS is 30 kHz / 60 kHz, dense-urban, lower latency, and wider carrier bandwidth can be supported. If SCS is 60 kHz or higher, bandwidths greater than 24.25 GHz can be supported to overcome phase noise.

[0045] The NR frequency band may be defined as two types of frequency range, i.e., Frequency Range 1 (FR1) and Frequency Range 2 (FR2). The numerical value of the frequency range may be changed. For example, the frequency ranges of the two types (FR1 and FR2) may be as shown in Table 1 below. For ease of explanation, in the frequency ranges used in the NR system, FR1 may mean "sub 6 GHz range", FR2 may mean "above 6 GHz range," and may be referred to as millimeter Wave (mmW).

[0046] Frequency Range designationCorresponding frequency rangeSubcarrier SpacingFR1450MHz - 6000MHz15, 30, 60kHzFR224250MHz - 52600MHz60, 120, 240kHz

[0047] As mentioned above, the numerical value of the frequency range of the NR system may be changed. For example, FR1 may include a frequency band of 410MHz to 7125MHz as shown in Table 2 below. That is, FR1 may include a frequency band of 6GHz (or 5850, 5900, 5925 MHz, etc.) or more. For example, a frequency band of 6 GHz (or 5850, 5900, 5925 MHz, etc.) or more included in FR1 may include an unlicensed band. Unlicensed bands may be used for a variety of purposes, for example for communication for vehicles (e.g., autonomous driving).

[0048] Frequency Range designationCorresponding frequency rangeSubcarrier SpacingFR1410MHz - 7125MHz15, 30, 60kHzFR224250MHz - 52600MHz60, 120, 240kHz

[0049] Here, the radio communication technologies implemented in the wireless devices in the present disclosure may include NarrowBand IoT (NB-IoT) technology for low-power communication as well as LTE, NR and 6G. For example, NB-IoT technology may be an example of Low Power Wide Area Network (LPWAN) technology, may be implemented in specifications such as LTE Cat NB1 and / or LTE Cat NB2, and may not be limited to the above-mentioned names. Additionally and / or alternatively, the radio communication technologies implemented in the wireless devices in the present disclosure may communicate based on LTE-M technology. For example, LTE-M technology may be an example of LPWAN technology and be called by various names such as enhanced MTC (eMTC). For example, LTE-M technology may be implemented in at least one of the 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-mentioned names. Additionally and / or alternatively, the radio communication technologies implemented in the wireless devices in the present disclosure may include at least one of ZigBee, Bluetooth, and / or LPWAN which take into account low-power communication, and may not be limited to the above-mentioned names. For example, ZigBee technology may generate Personal Area Networks (PANs) associated with small / low-power digital communication based on various specifications such as IEEE 802.15.4 and may be called various names.FIG. 2 shows an example of wireless devices to which implementations of the present disclosure is applied.

[0050] In FIG. 2, The first wireless device 100 and / or the second wireless device 200 may be implemented in various forms according to use cases / services. For example, {the first wireless device 100 and the second wireless device 200} may correspond to at least one of {the wireless device 100a to 100f and the BS 200}, {the wireless device 100a to 100f and the wireless device 100a to 100f} and / or {the BS 200 and the BS 200} of FIG. 1. The first wireless device 100 and / or the second wireless device 200 may be configured by various elements, devices / parts, and / or modules.

[0051] The first wireless device 100 may include at least one transceiver, such as a transceiver 106, at least one processing chip, such as a processing chip 101, and / or one or more antennas 108.

[0052] The processing chip 101 may include at least one processor, such a processor 102, and at least one memory, such as a memory 104. Additional and / or alternatively, the memory 104 may be placed outside of the processing chip 101.

[0053] The processor 102 may control the memory 104 and / or the transceiver 106 and may be adapted to implement the descriptions, functions, procedures, suggestions, methods and / or operational flowcharts described in the present disclosure. For example, the processor 102 may process information within the memory 104 to generate first information / signals and then transmit radio signals including the first information / signals through the transceiver 106. The processor 102 may receive radio signals including second information / signals through the transceiver 106 and then store information obtained by processing the second information / signals in the memory 104.

[0054] The memory 104 may be operably connectable to the processor 102. The memory 104 may store various types of information and / or instructions. The memory 104 may store a firmware and / or a software code 105 which implements codes, commands, and / or a set of commands that, when executed by the processor 102, perform the descriptions, functions, procedures, suggestions, methods and / or operational flowcharts disclosed in the present disclosure. For example, the firmware and / or the software code 105 may implement instructions that, when executed by the processor 102, perform the descriptions, functions, procedures, suggestions, methods and / or operational flowcharts disclosed in the present disclosure. For example, the firmware and / or the software code 105 may control the processor 102 to perform one or more protocols. For example, the firmware and / or the software code 105 may control the processor 102 to perform one or more layers of the radio interface protocol.

[0055] Herein, the processor 102 and the memory 104 may be a part of a communication modem / circuit / chip designed to implement RAT (e.g., LTE or NR). The transceiver 106 may be connected to the processor 102 and transmit and / or receive radio signals through one or more antennas 108. Each of the transceiver 106 may include a transmitter and / or a receiver. The transceiver 106 may be interchangeably used with Radio Frequency (RF) unit(s). In the present disclosure, the first wireless device 100 may represent a communication modem / circuit / chip.

[0056] The second wireless device 200 may include at least one transceiver, such as a transceiver 206, at least one processing chip, such as a processing chip 201, and / or one or more antennas 208.

[0057] The processing chip 201 may include at least one processor, such a processor 202, and at least one memory, such as a memory 204. Additional and / or alternatively, the memory 204 may be placed outside of the processing chip 201.

[0058] The processor 202 may control the memory 204 and / or the transceiver 206 and may be adapted to implement the descriptions, functions, procedures, suggestions, methods and / or operational flowcharts described in the present disclosure. For example, the processor 202 may process information within the memory 204 to generate third information / signals and then transmit radio signals including the third information / signals through the transceiver 206. The processor 202 may receive radio signals including fourth information / signals through the transceiver 106 and then store information obtained by processing the fourth information / signals in the memory 204.

[0059] The memory 204 may be operably connectable to the processor 202. The memory 204 may store various types of information and / or instructions. The memory 204 may store a firmware and / or a software code 205 which implements codes, commands, and / or a set of commands that, when executed by the processor 202, perform the descriptions, functions, procedures, suggestions, methods and / or operational flowcharts disclosed in the present disclosure. For example, the firmware and / or the software code 205 may implement instructions that, when executed by the processor 202, perform the descriptions, functions, procedures, suggestions, methods and / or operational flowcharts disclosed in the present disclosure. For example, the firmware and / or the software code 205 may control the processor 202 to perform one or more protocols. For example, the firmware and / or the software code 205 may control the processor 202 to perform one or more layers of the radio interface protocol.

[0060] Herein, the processor 202 and the memory 204 may be a part of a communication modem / circuit / chip designed to implement RAT (e.g., LTE or NR). The transceiver 206 may be connected to the processor 202 and transmit and / or receive radio signals through one or more antennas 208. Each of the transceiver 206 may include a transmitter and / or a receiver. The transceiver 206 may be interchangeably used with RF unit. In the present disclosure, the second wireless device 200 may represent a communication modem / circuit / chip.

[0061] Hereinafter, hardware elements of the wireless devices 100 and 200 will be described more specifically. One or more protocol layers may be implemented by, without being limited to, one or more processors 102 and 202. For example, the one or more processors 102 and 202 may implement one or more layers (e.g., functional layers such as Physical (PHY) layer, Media Access Control (MAC) layer, Radio Link Control (RLC) layer, Packet Data Convergence Protocol (PDCP) layer, Radio Resource Control (RRC) layer, and Service Data Adaptation Protocol (SDAP) layer). The one or more processors 102 and 202 may generate one or more Protocol Data Units (PDUs), one or more Service Data Unit (SDUs), messages, control information, data, or information according to the descriptions, functions, procedures, suggestions, methods and / or operational flowcharts disclosed in the present disclosure. The one or more processors 102 and 202 may generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data, or information according to the descriptions, functions, procedures, suggestions, methods and / or operational flowcharts disclosed in the present disclosure and provide the generated signals to the one or more transceivers 106 and 206. The one or more processors 102 and 202 may receive the signals (e.g., baseband signals) from the one or more transceivers 106 and 206 and acquire the PDUs, SDUs, messages, control information, data, or information according to the descriptions, functions, procedures, suggestions, methods and / or operational flowcharts disclosed in the present disclosure.

[0062] The one or more processors 102 and 202 may be referred to as controllers, microcontrollers, microprocessors, or microcomputers. The 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 the one or more processors 102 and 202. For example, the one or more processors 102 and 202 may be configured by a set of a communication control processor, an Application Processor (AP), an Electronic Control Unit (ECU), a Central Processing Unit (CPU), a Graphic Processing Unit (GPU), and a memory control processor.

[0063] The one or more memories 104 and 204 may be connected to the one or more processors 102 and 202 and store various types of data, signals, messages, information, programs, code, instructions, and / or commands. The 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 drive, register, cash memory, computer-readable storage medium, and / or combinations thereof. The one or more memories 104 and 204 may be located at the interior and / or exterior of the one or more processors 102 and 202. The one or more memories 104 and 204 may be connected to the one or more processors 102 and 202 through various technologies such as wired or wireless connection.

[0064] The 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. The 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, the one or more transceivers 106 and 206 may be connected to the one or more processors 102 and 202 and transmit and receive radio signals. For example, the one or more processors 102 and 202 may perform control so that the one or more transceivers 106 and 206 may transmit user data, control information, or radio signals to one or more other devices. The one or more processors 102 and 202 may perform control so that the one or more transceivers 106 and 206 may receive user data, control information, or radio signals from one or more other devices.

[0065] The one or more transceivers 106 and 206 may be connected to the one or more antennas 108 and 208. Additionally and / or alternatively, the one or more transceivers 106 and 206 may include one or more antennas 108 and 208. The 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, through the one or more antennas 108 and 208. In the present disclosure, the one or more antennas 108 and 208 may be a plurality of physical antennas or a plurality of logical antennas (e.g., antenna ports).

[0066] The one or more transceivers 106 and 206 may convert received user data, control information, radio signals / channels, etc., from RF band signals into baseband signals in order to process received user data, control information, radio signals / channels, etc., using the one or more processors 102 and 202. The one or more transceivers 106 and 206 may convert the user data, control information, radio signals / channels, etc., processed using the one or more processors 102 and 202 from the base band signals into the RF band signals. To this end, the one or more transceivers 106 and 206 may include (analog) oscillators and / or filters. For example, the one or more transceivers 106 and 206 can up-convert OFDM baseband signals to OFDM signals by their (analog) oscillators and / or filters under the control of the one or more processors 102 and 202 and transmit the up-converted OFDM signals at the carrier frequency. The one or more transceivers 106 and 206 may receive OFDM signals at a carrier frequency and down-convert the OFDM signals into OFDM baseband signals by their (analog) oscillators and / or filters under the control of the one or more processors 102 and 202.

[0067] Although not shown in FIG. 2, the wireless devices 100 and 200 may further include additional components. The additional components 140 may be variously configured according to types of the wireless devices 100 and 200. For example, the additional components 140 may include at least one of a power unit / battery, an Input / Output (I / O) device (e.g., audio I / O port, video I / O port), a driving device, and a computing device. The additional components 140 may be coupled to the one or more processors 102 and 202 via various technologies, such as a wired or wireless connection.

[0068] In the implementations of the present disclosure, a UE may operate as a transmitting device in Uplink (UL) and as a receiving device in Downlink (DL). In the implementations of the present disclosure, a BS may operate as a receiving device in UL and as a transmitting device in DL. Hereinafter, for convenience of description, it is mainly assumed that the first wireless device 100 acts as the UE, and the second wireless device 200 acts as the BS. For example, the processor(s) 102 connected to, mounted on or launched in the first wireless device 100 may be adapted to perform the UE behavior according to an implementation of the present disclosure or control the transceiver(s) 106 to perform the UE behavior according to an implementation of the present disclosure. The processor(s) 202 connected to, mounted on or launched in the second wireless device 200 may be adapted to perform the BS behavior according to an implementation of the present disclosure or control the transceiver(s) 206 to perform the BS behavior according to an implementation of the present disclosure.

[0069] In the present disclosure, a BS is also referred to as a node B (NB), an eNode B (eNB), or a gNB.

[0070] FIG. 3 shows an example of UE to which implementations of the present disclosure is applied.

[0071] Referring to FIG. 3, a UE 100 may correspond to the first wireless device 100 of FIG. 2.

[0072] A 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 Identification Module (SIM) card 145, a speaker 146, and a microphone 147.

[0073] The processor 102 may be adapted to implement the descriptions, functions, procedures, suggestions, methods and / or operational 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, procedures, suggestions, methods and / or operational flowcharts disclosed in the present disclosure. Layers of the radio interface protocol may be implemented in the processor 102. The processor 102 may include ASIC, other chipset, logic circuit and / or data processing device. The processor 102 may be an application processor. The processor 102 may include at least one of DSP, CPU, GPU, a modem (modulator and demodulator). An example of the processor 102 may be found in SNAPDRAGONTMseries of processors made by Qualcomm®, EXYNOSTMseries of processors made by Samsung®, A series of processors made by Apple®, HELIOTMseries of processors made by MediaTek®, ATOMTMseries of processors made by Intel®or a corresponding next generation processor.

[0074] The memory 104 is operatively coupled with the processor 102 and stores a variety of information to operate the processor 102. The memory 104 may include ROM, RAM, flash memory, memory card, storage medium and / or other storage device. When the embodiments are implemented in software, the techniques described herein can be implemented with modules (e.g., procedures, functions, etc.) that perform the descriptions, functions, procedures, suggestions, methods and / or operational flowcharts disclosed in the present disclosure. The modules can be stored in the memory 104 and executed by the processor 102. The memory 104 can be implemented within the processor 102 or external to the processor 102 in which case those can be communicatively coupled to the processor 102 via various means as is known in the art.

[0075] The transceiver 106 is operatively coupled with the processor 102, and transmits and / or receives a radio signal. The transceiver 106 includes a transmitter and a receiver. The transceiver 106 may include baseband circuitry to process radio frequency signals. The transceiver 106 controls the one or more antennas 108 to transmit and / or receive a radio signal.

[0076] The power management module 141 manages power for the processor 102 and / or the transceiver 106. The battery 142 supplies power to the power management module 141.

[0077] The display 143 outputs results processed by the processor 102. The keypad 144 receives inputs to be used by the processor 102. The keypad 144 may be shown on the display 143.

[0078] The SIM card 145 is an　integrated circuit　that is intended to　securely store the　International Mobile Subscriber Identity　(IMSI) number and its related　key, which are used to identify and authenticate subscribers on　mobile telephony　devices (such as　mobile phones　and　computers). It is also possible to store contact information on many SIM cards.

[0079] The speaker 146 outputs sound-related results processed by the processor 102. The microphone 147 receives sound-related inputs to be used by the processor 102.

[0080] FIGs. 4 and 5 show an example of protocol stacks in a 3GPP based wireless communication system to which implementations of the present disclosure is applied.

[0081] In particular, FIG. 4 illustrates an example of a radio interface user plane protocol stack between a UE and a BS and FIG. 5 illustrates an example of a radio interface control plane protocol stack between a UE and a BS. The control plane refers to a path through which control messages used to manage call by a UE and a network are transported. The user plane refers to a path through which data generated in an application layer, for example, voice data or Internet packet data are transported. Referring to FIG. 4, the user plane protocol stack may be divided into Layer 1 (L1, for example PHY layer) and Layer 2 (L2, for example MAC / RLC / PDCP layer). Referring to FIG. 5, the control plane protocol stack may be divided into Layer 1 (L1, for example PHY layer), Layer 2 (L2, for example MAC / RLC / PDCP layer), Layer 3 (L3, for example an RRC layer), and a non-access stratum (NAS) layer. Layer 1, Layer 2 and Layer 3 are referred to as an access stratum (AS).

[0082] In the 3GPP LTE system, the Layer 2 is split into the following sublayers: MAC, RLC, and PDCP. In the 3GPP NR system, the Layer 2 is split into the following sublayers: MAC, RLC, PDCP and SDAP. The PHY layer offers to the MAC sublayer transport channels, the MAC sublayer offers to the RLC sublayer logical channels, the RLC sublayer offers to the PDCP sublayer RLC channels, the PDCP sublayer offers to the SDAP sublayer radio bearers. The SDAP sublayer offers to 5G core network quality of service (QoS) flows.

[0083] In the 3GPP NR system, the main services and functions of the MAC sublayer include: mapping between logical channels and transport channels; multiplexing / de-multiplexing of MAC SDUs belonging to one or different logical channels into / from transport blocks (TB) delivered to / from the physical layer on transport channels; scheduling information reporting; error correction through hybrid automatic repeat request (HARQ) (one HARQ entity per cell in case of carrier aggregation (CA)); priority handling between UEs by means of dynamic scheduling; priority handling between logical channels of one UE by means of logical channel prioritization; padding. A single MAC entity may support multiple numerologies, transmission timings and cells. Mapping restrictions in logical channel prioritization control which numerology(ies), cell(s), and transmission timing(s) a logical channel can use.

[0084] Different kinds of data transfer services are offered by MAC. To accommodate different kinds of data transfer services, multiple types of logical channels are defined, i.e., each supporting transfer of a particular type of information. Each logical channel type is defined by what type of information is transferred. Logical channels are classified into two groups: control channels and traffic channels. Control channels are used for the transfer of control plane information only, and traffic channels are used for the transfer of user plane information only. Broadcast control channel (BCCH) is a downlink logical channel for broadcasting system control information, paging control channel (PCCH) is a downlink logical channel that transfers paging information, system information change notifications and indications of ongoing public warning service (PWS) broadcasts, common control channel (CCCH) is a logical channel for transmitting control information between UEs and network and used for UEs having no RRC connection with the network, and dedicated control channel (DCCH) is a point-to-point bi-directional logical channel that transmits dedicated control information between a UE and the network and used by UEs having an RRC connection. Dedicated traffic channel (DTCH) is a point-to-point logical channel, dedicated to one UE, for the transfer of user information. A DTCH can exist in both uplink and downlink. In downlink, the following connections between logical channels and transport channels exist: BCCH can be mapped to broadcast channel (BCH); BCCH can be mapped to downlink shared channel (DL-SCH); PCCH can be mapped to 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 uplink, the following connections between logical channels and transport channels exist: CCCH can be mapped to uplink shared channel (UL-SCH); DCCH can be mapped to UL-SCH; and DTCH can be mapped to UL-SCH.

[0085] The RLC sublayer supports three transmission modes: transparent mode (TM), unacknowledged mode (UM), and acknowledged node (AM). The RLC configuration is per logical channel with no dependency on numerologies and / or transmission durations. In the 3GPP NR system, the main services and functions of the RLC sublayer depend on the transmission mode and include: transfer of upper layer PDUs; sequence numbering independent of the one in PDCP (UM and AM); error correction through ARQ (AM only); segmentation (AM and UM) and re-segmentation (AM only) of RLC SDUs; reassembly of SDU (AM and UM); duplicate detection (AM only); RLC SDU discard (AM and UM); RLC re-establishment; protocol error detection (AM only).

[0086] 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-order delivery; PDCP PDU routing (in case of split bearers); retransmission of PDCP SDUs; ciphering, deciphering 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 duplicate discard indication to lower layers. The main services and functions of the PDCP sublayer for the control plane include: sequence numbering; ciphering, deciphering and integrity protection; transfer of control plane data; reordering and duplicate detection; in-order delivery; duplication of PDCP PDUs and duplicate discard indication to lower layers.

[0087] In the 3GPP NR system, the main services and functions of SDAP include: mapping between a QoS flow and a data radio bearer; marking QoS flow ID (QFI) in both DL and UL packets. A single protocol entity of SDAP is configured for each individual PDU session.

[0088] In the 3GPP NR system, the main services and functions of the RRC sublayer include: broadcast of system information related to AS and NAS; paging initiated by 5GC or NG-RAN; establishment, maintenance and release of an RRC connection between the UE and NG-RAN; security functions including key management; establishment, configuration, maintenance and release of signalling 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; UE measurement reporting and control of the reporting; detection of and recovery from radio link failure; NAS message transfer to / from NAS from / to UE.

[0089] FIG. 6 shows a frame structure in a 3GPP based wireless communication system to which implementations of the present disclosure is applied.

[0090] The frame structure shown in FIG. 6 is purely exemplary and the number of subframes, the number of slots, and / or the number of symbols in a frame may be variously changed. In the 3GPP based wireless communication system, OFDM numerologies (e.g., subcarrier spacing (SCS), transmission time interval (TTI) duration) may be differently configured between a plurality of cells aggregated for one UE. For example, if a UE is configured with different SCSs for cells aggregated for the cell, an (absolute time) duration of a time resource (e.g., a subframe, a slot, or a TTI) including the same number of symbols may be different among the aggregated cells. Herein, symbols may include OFDM symbols (or CP-OFDM symbols), SC-FDMA symbols (or discrete Fourier transform-spread-OFDM (DFT-s-OFDM) symbols).

[0091] Referring to FIG. 6, downlink and uplink transmissions are organized into frames. Each frame has Tf= 10ms duration. Each frame is divided into two half-frames, where each of the half-frames has 5ms duration. Each half-frame consists of 5 subframes, where the duration Tsfper subframe is 1ms. Each subframe is divided into slots and the number of slots in a subframe depends on a subcarrier spacing. Each slot includes 14 or 12 OFDM symbols based on a cyclic prefix (CP). In a normal CP, each slot includes 14 OFDM symbols and, in an extended CP, each slot includes 12 OFDM symbols. The numerology is based on exponentially scalable subcarrier spacing f = 2u*15 kHz.

[0092] Table 3 shows the number of OFDM symbols per slot Nslotsymb, the number of slots per frameNframe,uslot, and the number of slots per subframe Nsubframe,uslotfor the normal CP, according to the subcarrier spacing f = 2u*15 kHz.

[0093] uNslotsymbNframe,uslotNsubframe,uslot01410111420221440431480841416016

[0094] Table 4 shows the number of OFDM symbols per slot Nslotsymb, the number of slots per frameNframe,uslot, and the number of slots per subframe Nsubframe,uslotfor the extended CP, according to the subcarrier spacing f = 2u*15 kHz.

[0095] uNslotsymbNframe,uslotNsubframe,uslot212404

[0096] A slot includes plural symbols (e.g., 14 or 12 symbols) in the time domain. For each numerology (e.g., subcarrier spacing) and carrier, a resource grid ofNsize,ugrid,x*NRBscsubcarriers andNsubframe,usymbOFDM symbols is defined, starting at common resource block (CRB)Nstart,ugridindicated by higher-layer signalling (e.g., RRC signalling), whereNsize,ugrid,xis the number of resource blocks (RBs) in the resource grid and the subscript x is DL for downlink and UL for uplink.NRBscis the number of subcarriers per RB. In the 3GPP based wireless communication system,NRBscis 12 generally. There is one resource grid for a given antenna portp, subcarrier spacing configurationu, and transmission direction (DL or UL). The carrier bandwidthNsize,ugridfor subcarrier spacing configurationuis given by the higher-layer parameter (e.g., RRC parameter). Each element in the resource grid for the antenna portpand the subcarrier spacing configurationuis referred to as a resource element (RE) and one complex symbol may be mapped to each RE. Each RE in the resource grid is uniquely identified by an indexkin the frequency domain and an indexlrepresenting a symbol location relative to a reference point in the time domain. In the 3GPP based wireless communication system, an RB is defined by 12 consecutive subcarriers in the frequency domain. As shown in FIG. 6, as SCS doubles, the slot length and symbol length are halved. For example, when SCS is 15kHz, the slot length is 1ms, which is the same as the subframe length. When SCS is 30kHz, the slot length is 0.5ms (=500us), and the symbol length is half of that when the SCS is 15kHz. When SCS is 60kHz, the slot length is 0.25ms (=250us), and the symbol length is half of that when the SCS is 30kHz. When SCS is 120kHz, the slot length is 0.125ms (=125us), and the symbol length is half of that when the SCS is 60kHz. When SCS is 240kHz, the slot length is 0.0625ms (=62.5us), and the symbol length is half of that when the SCS is 120kHz.

[0097] In the 3GPP NR system, RBs are classified into CRBs and physical resource blocks (PRBs). CRBs are numbered from 0 and upwards in the frequency domain for subcarrier spacing configurationu. The center of subcarrier 0 of CRB 0 for subcarrier spacing configurationucoincides with 'point A' which serves as a common reference point for resource block grids. In the 3GPP NR system, PRBs are defined within a bandwidth part (BWP) and numbered from 0 toNsizeBWP,i-1, where i is the number of the bandwidth part. The relation between the physical resource block nPRBin the bandwidth part i and the common resource block nCRBis as follows: nPRB= nCRB+NsizeBWP,i, whereNsizeBWP,iis the common resource block where bandwidth part starts relative to CRB 0. The BWP includes a plurality of consecutive RBs. A carrier may include a maximum of N (e.g., 5) BWPs. A UE may be configured with one or more BWPs on a given component carrier. Only one BWP among BWPs configured to the UE can active at a time. The active BWP defines the UE's operating bandwidth within the cell's operating bandwidth.

[0098] In the present disclosure, the term "cell" may refer to a geographic area to which one or more nodes provide a communication system, or refer to radio resources. A "cell" as a geographic area may be understood as coverage within which a node can provide service using a carrier and a "cell" as radio resources (e.g., time-frequency resources) is associated with bandwidth which is a frequency range configured by the carrier. The "cell" associated with the radio resources is defined by a combination of downlink resources and uplink resources, for example, a combination of a DL component carrier (CC) and a UL CC. The cell may be configured by downlink resources only, or may be configured by downlink resources and uplink resources. Since DL coverage, which is a range within which the node is capable of transmitting a valid signal, and UL coverage, which is a range within which the node is capable of receiving the valid signal from the UE, depends upon a carrier carrying the signal, the coverage of the node may be associated with coverage of the "cell" of radio resources used by the node. Accordingly, the term "cell" may be used to represent service coverage of the node sometimes, radio resources at other times, or a range that signals using the radio resources can reach with valid strength at other times.

[0099] In CA, two or more CCs are aggregated. A UE may simultaneously receive or transmit on one or multiple CCs depending on its capabilities. CA is supported for both contiguous and non-contiguous CCs. When CA is configured, the UE only has one RRC connection with the network. At RRC connection establishment / re-establishment / handover, one serving cell provides the NAS mobility information, and at RRC connection re-establishment / handover, one serving cell provides the security input. This cell is referred to as the primary cell (PCell). The PCell is a cell, operating on the primary frequency, in which the UE either performs the initial connection establishment procedure or initiates the connection re-establishment procedure. Depending on UE capabilities, secondary cells (SCells) can be configured to form together with the PCell a set of serving cells. An SCell is a cell providing additional radio resources on top of special cell (SpCell). The configured set of serving cells for a UE therefore 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). An SpCell supports PUCCH transmission and contention-based random access, and is always activated. The MCG is a group of serving cells associated with a master node, comprised of the SpCell (PCell) and optionally one or more SCells. The SCG is the subset of serving cells associated with a secondary node, comprised of the PSCell and zero or more SCells, for a UE configured with DC. For a UE in RRC_CONNECTED not configured with CA / DC, there is only one serving cell comprised of the PCell. For a UE in RRC_CONNECTED configured with CA / DC, the term "serving cells" is used to denote the set of cells comprised of the SpCell(s) and all SCells. In DC, two MAC entities are configured in a UE: one for the MCG and one for the SCG.

[0100] FIG. 7 shows a data flow example in the 3GPP NR system to which implementations of the present disclosure is applied.

[0101] Referring to FIG. 7, "RB" denotes a radio bearer, and "H" denotes a header. Radio bearers are categorized into two groups: DRBs for user plane data and SRBs for control plane data. The MAC PDU is transmitted / received using radio resources through the PHY layer to / from an external device. The MAC PDU arrives to the PHY layer in the form of a transport block.

[0102] In the PHY layer, the uplink transport channels UL-SCH and random access channel (RACH) are mapped to their physical channels physical uplink shared channel (PUSCH) and physical random access channel (PRACH), respectively, and the downlink transport channels DL-SCH, BCH and PCH are mapped to physical downlink shared channel (PDSCH), physical broadcast channel (PBCH) and PDSCH, respectively. In the PHY layer, uplink control information (UCI) is mapped to physical uplink control channel (PUCCH), and downlink control information (DCI) is mapped to physical downlink control channel (PDCCH). A MAC PDU related to UL-SCH is transmitted by a UE via a PUSCH based on an UL grant, and a MAC PDU related to DL-SCH is transmitted by a BS via a PDSCH based on a DL assignment.

[0103] Hereinafter, a description will be given of mobility.

[0104] The mobility may comprise PCell change, PSCell change (or, secondary node (SN) change), and / or PSCell addition (or, SN addition).

[0105] In the present disclosure, the term "handover (HO)" may mean PCell change, or may be a broad concept that includes not only PCell change but also PSCell change / addition.

[0106] In the present disclosure, the terms "handover" and "mobility" can be used interchangeably.

[0107] In the present disclosure, the description regarding handover can also be applied to other mobility procedures (e.g., PSCell change / addition).

[0108] There may be at least two types of mobility: network-controlled mobility (or, legacy mobility) and UE-based mobility (or, conditional mobility).

[0109] The network-controlled mobility (or, legacy mobility) is a mobility where the network determines a target cell for mobility, and configures UE with the target cell. The network may transmit, to the UE, anRRCReconfigurationmessage comprising a configuration of the target cell. The UE may execute a mobility to the target cell and / or apply the configuration of the target cell, upon receiving the configuration of the target cell.

[0110] The UE-based mobility (or, conditional mobility) is a mobility where the network configures the UE with a plurality of candidate cells, and the UE determines a target cell which satisfies a mobility execution condition among the plurality of candidate cells. The conditional mobility may comprise at least one of a conditional PCell change / conditional handover (CHO) or a conditional PSCell mobility. The conditional PSCell mobility may comprise conditional PSCell addition / change (CPAC), including conditional PSCell addition (CPA) and / or conditional PSCell change (CPC). The network may transmit, to the UE, anRRCReconfigurationmessage comprisingConditionalReconfigurationinformation element (IE)(or, conditional mobility configuration), which comprises a list of candidate configurations for conditional mobility related to the plurality of candidate cells. A candidate configuration for conditional mobility may comprise an identifier of the candidate configuration, a mobility execution condition for the related candidate cell, and a configuration of the related candidate cell. The UE may evaluate the mobility execution conditions for the plurality of candidate cells, and when a mobility execution condition for a candidate cell is satisfied, the UE may consider the candidate cell as a target cell, and execute a mobility to the target cell and / or apply the configuration of the target cell.

[0111] According to various embodiments, the mobility execution condition may be satisfied / met when an entry condition (or, entering condition) for the mobility execution condition is satisfied / met for at least a time-to-trigger (TTT) for the mobility execution condition. The entry condition / entering condition may mean that the mobility execution condition is initially met. Once the entry condition is met, the mobility execution condition will be considered to be met if the entry condition is met for time duration TTT continuously.

[0112] FIG. 8 shows an example of a conditional mobility procedure according to an embodiment of the present disclosure.

[0113] In FIG. 8:

[0114] - the serving BS may be related to a PCell, which may be a source PCell for CHO;

[0115] - the serving BS may be an MN associated with an SN in DC, where the SN may be related to a source PSCell for CPC; and

[0116] - the target cell may be a target PCell for CHO, or a target PSCell for CPA / CPC.

[0117] Referring to FIG. 8, in step S801, UE may receive, from the serving BS, anRRCReconfigurationmessage comprising a conditional reconfiguration information element (IE) (i.e.,CondidtionalReconfiguration). The conditional reconfiguration IE may comprise a list of candidate configurations for conditional mobility related to candidate cells including the target cell. Each candidate configuration in the list may be related to the corresponding candidate cell, and comprises i) an identifier of the corresponding candidate configuration (i.e.,condReconfigId), ii) one or more execution conditions for the related candidate cell (i.e.,condExecutionCond), and / or iii) RRC reconfiguration for the related candidate cell (i.e.,condRRCReconfig) including a configuration of the related candidate cell. The one or more execution conditions may comprise CHO execution condition(s), CPA execution condition(s), and / or CPC execution condition(s).

[0118] In step S803, the UE may start evaluating the one or more execution conditions for the candidate cells.

[0119] In step S805, if the target cell satisfies the corresponding execution condition(s), the UE may execute the conditional mobility towards the target cell and / or apply the RRC reconfiguration for the target cell including a configuration of the target cell. When / upon executing the conditional mobility and / or applying the RRC reconfiguration (e.g.,RRCReconfigurationincludingReconfigurationWithSync) for the target cell, the UE may start a timer (e.g., T304 timer). The timer value of the T304 timer (i.e., T304 timer value) for the target cell may be included in theReconfigurationWithSyncinRRCReconfigurationfor the target cell.

[0120] While the timer is running, the UE may perform DL synchronization and / or UL synchronization (e.g., random access) towards the target cell. The UE may skip the random access towards the target cell if timing advance (TA) information for the target cell is available.

[0121] In step S807, the UE, serving BS and / or BS related to the target cell may perform actions related to conditional mobility completion. For example, upon successful completion of the random access on the corresponding target cell, the UE may stop the timer (e.g., T304 timer).

[0122] The IEs in theConditionalReconfigurationare shown in table 5:

[0123] ConditionalReconfiguration-r16 ::= SEQUENCE {attemptCondReconfig-r16 ENUMERATED {true} OPTIONAL, -- Cond CHOcondReconfigToRemoveList-r16 CondReconfigToRemoveList-r16 OPTIONAL, -- Need NcondReconfigToAddModList-r16 CondReconfigToAddModList-r16 OPTIONAL, -- Need N...,[[scpac-ReferenceConfiguration-r18 SetupRelease {ReferenceConfiguration-r18} OPTIONAL, -- Need MservingSecurityCellSetId-r18 SecurityCellSetId-r18 OPTIONAL, -- Need Msk-CounterConfiguration-r18 SK-CounterConfiguration-r18 OPTIONAL -- Need M]]}CondReconfigToRemoveList-r16 ::= SEQUENCE (SIZE (1.. maxNrofCondCells-r16)) OF CondReconfigId-r16SK-CounterConfiguration-r18 ::= SEQUENCE {sk-CounterConfigToReleaseList-r18 SEQUENCE (SIZE (1..maxSecurityCellSet-r18)) OF SecurityCellSetId-r18 OPTIONAL, -- Need Nsk-CounterConfigToAddModList-r18 SEQUENCE (SIZE (1..maxSecurityCellSet-r18)) OF SK-CounterConfig-r18 OPTIONAL -- Need N}SK-CounterConfig-r18 ::= SEQUENCE {securityCellSetId-r18 SecurityCellSetId-r18,sk-CounterList-r18 SEQUENCE (SIZE (1..maxSK-Counter-r18)) OF SK-Counter}SecurityCellSetId-r18 ::= INTEGER (1.. maxSecurityCellSet-r18)

[0124] In table 5:

[0125] -attemptCondReconfig: if present, the UE shall perform conditional reconfiguration if selected cell is a target candidate cell and it is the first cell selection after failure;

[0126] -condReconfigToAddModList: list of the configuration of candidate SpCells to be added or modified for CHO, CPA or CPC;

[0127] -condReconfigToRemoveList: list of the configuration of candidate SpCells to be removed;

[0128] -scpac-ReferenceConfiguration: includes the reference configuration for the candidate supporting subsequent CPAC;

[0129] -servingSecurityCellSetId: this field identifies the security cell set for serving PSCell. The network does not provide this field for the conditional reconfiguration(s) generated by the SN; and

[0130] -sk-counterConfiguration: includes a list ofsk-Counterfrom which the UE should selectthe sk-counterused to derive S-KgNB for inter-SN subsequent CPAC. The network does not provide this field for the conditional reconfiguration(s) generated by the SN.

[0131] The IEs in thecondReconfigToAddModListare shown in table 6:

[0132] CondReconfigToAddModList-r16 ::= SEQUENCE (SIZE (1.. maxNrofCondCells-r16)) OF CondReconfigToAddMod-r16CondReconfigToAddMod-r16 ::= SEQUENCE {condReconfigId-r16 CondReconfigId-r16,condExecutionCond-r16 SEQUENCE (SIZE (1..2)) OF MeasId OPTIONAL, -- Need McondRRCReconfig-r16 OCTET STRING (CONTAINING RRCReconfiguration) OPTIONAL, -- Cond condReconfigAdd...,[[condExecutionCondSCG-r17 OCTET STRING (CONTAINING CondReconfigExecCondSCG-r17) OPTIONAL -- Need M]],[[condExecutionCondPSCell-r18 SEQUENCE (SIZE (1..2)) OF MeasId OPTIONAL, -- Cond condReconfigCHO-WithSCGsubsequentCondReconfig-r18 SubsequentCondReconfig-r18 OPTIONAL, -- Need MsecurityCellSetId-r18 SecurityCellSetId-r18 OPTIONAL, -- Need Mscpac-ConfigComplete-r18 ENUMERATED {true} OPTIONAL -- Cond CPAC]]}CondReconfigExecCondSCG-r17 ::= SEQUENCE (SIZE (1..2)) OF MeasIdSubsequentCondReconfig-r18 ::= SEQUENCE {condExecutionCondToReleaseList-r18 CondExecutionCondToReleaseList-r18 condExecutionCondToAddModList-r18 CondExecutionCondToAddModList-r18 ...OPTIONAL, -- Need NOPTIONAL, -- Need N}CondExecutionCondToAddModList-r18 ::= SEQUENCE (SIZE (1.. maxNrofCondCells-r16)) OF CondExecutionCondToAddMod-r18CondExecutionCondToAddMod-r18 ::= SEQUENCE {subsequentCondReconfigId-r18 CondReconfigId-r16,subsequentCondExecutionCond-r18 SEQUENCE (SIZE (1..2)) OF MeasId OPTIONAL, -- Need MsubsequentCondExecutionCondSCG-r18 OCTET STRING (CONTAINING CondReconfigExecCondSCG-r17) OPTIONAL, -- Need M...}CondExecutionCondToReleaseList-r18 ::= SEQUENCE (SIZE (1.. maxNrofCondCells-r16)) OF CondReconfigId-r16

[0133] In table 6:

[0134] -condExecutionCond: the execution condition that needs to be fulfilled in order to trigger the execution of a conditional reconfiguration for CHO, CPA, intra-SN CPC without MN involvement, MN initiated inter-SN CPC, MN initiated subsequent CPAC, or SN initiated intra-SN subsequent CPAC without MN involvement. When configuring 2 triggering events (MeasIds) for a candidate cell, the network ensures that both refer to the samemeasObject. The network configures at most one fromcondEventD1,condEventD2orcondEventT1for the same candidate cell. For CPA, MN-initiated inter-SN CPC, and for MN initiated subsequent CPAC, the network only indicatesMeasId(s) associated withcondEventA4. For intra-SN CPC and for SN initiated intra-SN subsequent CPAC without MN involvement, the network only indicatesMeasId(s) associated withcondEventA3orcondEventA5;

[0135] -condExecutionCondPSCell: the execution condition that needs to be fulfilled for the associated PSCell in order to trigger the execution of a conditional reconfiguration for CHO with candidate SCG(s). TheMeasIdsrefer to themeasConfigassociated with the MCG. When configuring 2 triggering events (MeasIds) for a candidate cell, network ensures that both refer to the samemeasObject. The network only indicatesMeasId(s) associated withcondEventA4;

[0136] -condExecutionCondSCG: contains execution condition that needs to be fulfilled in order to trigger the execution of a conditional reconfiguration for SN initiated inter-SN CPC, SN initiated inter-SN subsequent CPAC, or SN initiated intra-SN subsequent CPAC with MN involvement. TheMeasIds refer to themeasConfigassociated with the SCG. When configuring 2 triggering events (MeasIds) for a candidate cell, network ensures that both refer to the samemeasObject. For eachcondReconfigId, the network always configures eithercondExecutionCondorcondExecutionCondSCG(not both). The network only indicatesMeasId(s) associated withcondEventA3orcondEventA5;

[0137] -condRRCReconfig: theRRCReconfigurationmessage to be applied when the condition(s) are fulfilled. TheRRCReconfigurationmessage contained incondRRCReconfigcannot contain the fieldconditionalReconfigurationor the fielddaps-Config;

[0138] -securityCellSetId: this field is used to determine whether the UE should perform security update when conditional reconfiguration containingsubsequentCondReconfigis executed. If the fieldservingSecurityCellSetIdis configured inconditionalReconfiguration, this field is configured for all the candidate configurations for subsequent CPAC;

[0139] -subsequentCondReconfig: contains the execution conditions that need to be fulfilled in order to trigger the execution of a subsequent CPAC. If the field is configured, the configuration of candidate PSCells for subsequent CPAC is supported. The subsequent execution condition is used for conditional reconfiguration evaluation for other candidate cells when theRRCReconfigurationmessage contained incondRRCReconfighas been applied;

[0140] -subsequentCondExecutionCond: the execution condition that needs to be fulfilled in order to trigger the subsequent execution of a conditional reconfiguration for SN initiated intra-SN subsequent CPAC without MN involvement. When configuring 2 triggering events (MeasIds) for a candidate cell, the network ensures that both refer to the samemeasObject. The network only indicatesMeasId(s) associated withcondEventA3orcondEventA5; and

[0141] -subsequentCondExecutionCondSCG: contains execution condition that needs to be fulfilled in order to trigger the subsequent execution of a conditional reconfiguration for SN initiated inter-SN subsequent CPAC, SN initiated intra-SN subsequent CPAC with MN involvement, or MN initiated subsequent CPAC. TheMeasIds refer to themeasConfigassociated with the SCG. When configuring 2 triggering events (MeasIds) for a candidate cell, network ensures that both refer to the samemeasObject. The network only indicatesMeasId(s) associated withcondEventA3orcondEventA5.

[0142] Hereinafter, detailed procedure of the conditional reconfiguration / mobility is described.

[0143] The network configures the UE with one or more candidate target SpCells in the conditional reconfiguration. The UE evaluates the condition (e.g.,condExecutionCond) of each configured candidate target SpCell. The UE applies the conditional reconfiguration (e.g.,condRRCConfig / RRCReconfiguration) associated with one of the target SpCells which fulfils associated execution condition.

[0144] The network can also configure the UE with one or more candidate target PCells associated with one or more candidate target PSCells. In the present disclosure, "associated candidate (target) PSCell (or, candidate (target) PSCell related to / associated with candidate (target) PCell)" refers to a candidate (target) PSCell of which configuration (e.g.,RRCReconfiguration) is included in SCG configuration (e.g.,mrdc-SecondaryCellGroup / nr-SCG) in a configuration (e.g.,condRRCConfig / RRCReconfiguration) of a candidate (target) PCell. The UE evaluates the conditions (e.g.,condExecutionCond) for the candidate target PCells and the conditions (e.g.,condExecutionCondPSCell) for the associated candidate target PSCells in parallel and applies a target configuration that include PCell and PSCell for which the associated execution conditions are fulfilled. That is, the UE applies a configuration (e.g.,RRCReconfiguration) of the candidate (target) PCell and a configuration (e.g.,RRCReconfiguration) of the candidate (target) PSCell when both of the conditions (e.g.,condExecutionCond) for the candidate (target) PCell and the conditions (e.g.,condExecutionCond) for the candidate (target) PSCell are fulfilled. If there are multiple candidate PSCells associated with one candidate target PCell, the network provides multiple conditional configurations for the same candidate target PCell, i.e., each configuration contains one MCG configuration (for the same candidate target PCell) and one SCG configuration (for one of the multiple associated candidate PSCells). For this case, the network may also provide a complementary CHO only configuration, i.e., there is execution condition only for candidate PCell.

[0145] The network provides the configuration parameters for the target SpCell(s) in thecondRRCReconfig.

[0146] In NR-DC, the UE may receive two independentconditionalReconfiguration:

[0147] - aconditionalReconfigurationassociated with MCG, that is included in theRRCReconfigurationmessage received via SRB1; and

[0148] - aconditionalReconfiguration, associated with SCG, that is included in theRRCReconfigurationmessage received via SRB3, or, alternatively, included within aRRCReconfigurationmessage embedded in aRRCReconfigurationmessage received via SRB1.

[0149] In this case:

[0150] - the UE maintains two independentVarConditionalReconfig, one associated with eachconditionalReconfiguration;

[0151] - the UE independently performs all the conditional reconfiguration procedures for eachconditionalReconfigurationand the associatedVarConditionalReconfig, unless explicitly stated otherwise;

[0152] - the UE performs the measurement procedures for theVarConditionalReconfigassociated with the same cell group like themeasConfig.

[0153] In EN-DC, theVarConditionalReconfigis associated with the SCG.

[0154] In NE-DC and when no SCG is configured, theVarConditionalReconfigis associated with the MCG.

[0155] The UE performs the following actions based on a receivedConditionalReconfigurationIE:

[0156] 1> if theConditionalReconfigurationcontains thecondReconfigToRemoveList:

[0157] 2> perform conditional reconfiguration removal procedure;

[0158] 1> if theConditionalReconfigurationcontains thecondReconfigToAddModList:

[0159] 2> perform conditional reconfiguration addition / modification;

[0160] 1> if theConditionalReconfigurationcontains thescpac-ReferenceConfiguration:

[0161] 2> perform subsequent CPAC reference configuration addition / removal;

[0162] 1> if theConditionalReconfigurationcontains thesk-CounterConfiguration:

[0163] 2> performsk-CounterListaddition / modification / removal;

[0164] 1> if theConditionalReconfigurationcontains theservingSecurityCellSetId:

[0165] 2> if the currentVarServingSecurityCellSetIDincludesservingSecurityCellSetId:

[0166] 3> replace theservingSecurityCellSetIdvalue withinVarServingSecurityCellSetIDwith the receivedservingSecurityCellSetID;

[0167] 2> else:

[0168] 3> store the receivedservingSecurityCellSetIdwithinVarServingSecurityCellSetID.

[0169] I. Conditional reconfiguration addition / modification

[0170] For eachcondReconfigIdreceived in thecondReconfigToAddModListIE the UE shall:

[0171] 1> if an entry with the matchingcondReconfigIdexists in thecondReconfigToAddModListwithin theVarConditionalReconfig:

[0172] 2> if the entry incondReconfigToAddModListincludes ancondExecutionCond,condExecutionCondSCG, orcondExecutionCondPSCell;

[0173] 3> replacecondExecutionCond,condExecutionCondSCG, orcondExecutionCondPSCellwithin theVarConditionalReconfigwith the value received for thiscondReconfigId;

[0174] 2> if the entry incondReconfigToAddModListincludessubsequentCondReconfigcontainingcondExecutionCondToAddModList:

[0175] 3> for eachcondReconfigIdreceived incondExecutionCondToAddModList:

[0176] 4> if an entry with the matchingcondReconfigIdexists in thecondExecutionCondToAddModListwithinVarConditionalReconfig;

[0177] 5> replace the entry incondExecutionCondToAddModListwithinVarConditionalReconfigwith the value received for thiscondReconfigId;

[0178] 4> else:

[0179] 5> add a new entry incondExecutionCondToAddModListwithinVarConditionalReconfigwith the value received for thiscondReconfigId;

[0180] 2> if the entry incondReconfigToAddModListincludessubsequentCondReconfigcontainingcondExecutionCondToReleaseList:

[0181] 3> for eachcondReconfigIdreceived incondExecutionCondToReleaseListthat is part of current storedcondExecutionCondToAddModListwithinVarConditionalReconfig:

[0182] 4> remove the entry incondExecutionCondToAddModListwithinVarConditionalReconfigwith the value received for thiscondReconfigId;

[0183] The UE does not consider the message as erroneous if thecondExecutionCondToReleaseListincludes anycondReconfigIdvalue that is not part of the current UE configuration.

[0184] 2> if the entry incondReconfigToAddModListincludes asecurityCellSetId;

[0185] 3> replacesecurityCellSetIdwithin theVarConditionalReconfigwith the value received for thiscondReconfigId;

[0186] The UE should release the entry withinVarServingSecurityCellSetIDin case all the subsequent CPAC configurations are released.

[0187] 2> if the entry incondReconfigToAddModListincludes acondRRCReconfig;

[0188] 3> replacecondRRCReconfigwithin theVarConditionalReconfigwith the value received for thiscondReconfigId;

[0189] 1> else:

[0190] 2> add a new entry for thiscondReconfigIdwithin theVarConditionalReconfig;

[0191] 1> perform conditional reconfiguration evaluation.

[0192] II. Conditional reconfiguration evaluation

[0193] The UE shall:

[0194] 1> for eachcondReconfigIdwithin theVarConditionalReconfig:

[0195] 2> if theRRCReconfigurationwithincondRRCReconfigincludes themasterCellGroupincluding thereconfigurationWithSync:

[0196] 3> if the associatedcondExecutionCondPSCellis configured:

[0197] 4> consider the cell which has a physical cell identity matching the value indicated in theServingCellConfigCommonincluded in thereconfigurationWithSyncwithin themasterCellGroupin the receivedcondRRCReconfigto be applicable cell; and

[0198] 4> consider the cell which has a physical cell identity matching the value indicated in theServingCellConfigCommonincluded in thereconfigurationWithSyncwithin thesecondaryCellGroupwithin thenr-SCGwithin the receivedcondRRCReconfigto be applicable cell;

[0199] 3> else:

[0200] 4> consider the cell which has a physical cell identity matching the value indicated in theServingCellConfigCommonincluded in thereconfigurationWithSyncwithin themasterCellGroupin the receivedcondRRCReconfigto be applicable cell;

[0201] 2> else if theRRCReconfigurationwithincondRRCReconfigincludes thesecondaryCellGroupincluding thereconfigurationWithSync:

[0202] 3> if the cell which has a physical cell identity matching the value indicated in theServingCellConfigCommonincluded in thereconfigurationWithSyncwithin thesecondaryCellGroupwithin the receivedcondRRCReconfigis not the PSCell:

[0203] 4> ifsubsequentCondReconfigis not included for thecondReconfigId; or

[0204] 4> ifsubsequentCondReconfigis not included for the PSCell; or

[0205] 4> ifsubsequentCondReconfigis included for thecondReconfigIdand there is asubsequentCondReconfigfor the PSCell with a matchingcondReconfigIdvalue incondExecutionCondToAddModList:

[0206] 5> consider the cell to be applicable cell;

[0207] 2> ifcondExecutionCondSCGis configured:

[0208] 3> in the remainder of the procedure, consider eachmeasIdindicated in thecondExecutionCondSCGas ameasIdin theVarMeasConfigassociated with the SCGmeasConfig;

[0209] 2> if thecondExecutionCondPSCellis configured:

[0210] 3> in the remainder of the procedure, consider eachmeasIdindicated in thecondExecutionCondPSCellas ameasIdin theVarMeasConfigassociated with the MCGmeasConfig;

[0211] 2> ifcondExecutionCondis configured:

[0212] 3> if it is configured via SRB3 or configured withinnr-SCGor withinnr-SecondaryCellGroupConfigvia SRB1:

[0213] 4> in the remainder of the procedure, consider eachmeasIdindicated in thecondExecutionCondas ameasIdin theVarMeasConfigassociated with the SCGmeasConfig;

[0214] 3> else:

[0215] 4> in the remainder of the procedure, consider eachmeasIdindicated in thecondExecutionCondas ameasIdin theVarMeasConfigassociated with the MCGmeasConfig;

[0216] 2> for eachmeasIdincluded in themeasIdListwithinVarMeasConfigindicated in thecondExecutionCond, condExecutionCondSCG,orcondExecutionCondPSCellof thecondReconfigId:

[0217] 3> ifcondExecutionCond,condExecutionCondSCG, andsubsequentCondReconfigare included for thecondReconfigId:

[0218] 4> ignore themeasId(s)in thecondExecutionCondof thecondReconfigId;

[0219] 3> if thecondTriggerConfigis not configured withnesEvent:

[0220] 4> if thecondEventIdis associated withcondEventT1, and if the entry condition applicable for this event associated with thecondReconfigId, i.e. the event corresponding with thecondEventId(s)of the correspondingcondTriggerConfigwithinVarConditionalReconfig, is fulfilled for the applicable cell; or

[0221] 4> if thecondEventIdis associated withcondEventD1orcondEventD2, and if the entry conditions applicable for this event associated with thecondReconfigId, i.e. the event corresponding with thecondEventId(s)of the correspondingcondTriggerConfigwithinVarConditionalReconfig, is fulfilled for the applicable cell during the correspondingtimeToTriggerdefined for this event within theVarConditionalReconfig; or

[0222] 4> if thecondEventIdis associated withcondEventA3,condEventA4orcondEventA5, and if the entry condition(s) applicable for this event associated with thecondReconfigId, i.e. the event corresponding with thecondEventId(s)of the correspondingcondTriggerConfigwithinVarConditionalReconfig, is fulfilled for the applicable cells for all measurements after layer 3 filtering taken during the correspondingtimeToTriggerdefined for this event within theVarConditionalReconfig:

[0223] 5> consider the event associated to thatmeasIdto be fulfilled;

[0224] 4> if themeasIdfor this event associated with thecondReconfigIdhas been modified; or

[0225] 4> if thecondEventIdis associated withcondEventT1, and if the leaving condition applicable for this event associated with thecondReconfigId, i.e. the event corresponding with thecondEventId(s)of the correspondingcondTriggerConfigwithinVarConditionalReconfig, is fulfilled for the applicable cell; or

[0226] 4>if thecondEventIdis associated withcondEventD1orcondEventD2, and if the leaving condition(s) applicable for this event associated with thecondReconfigId, i.e. the event corresponding with thecondEventId(s)of the correspondingcondTriggerConfigwithinVarConditionalReconfig, is fulfilled for the applicable cell during the correspondingtimeToTriggerdefined for this event within theVarConditionalReconfig; or

[0227] 4> if thecondEventIdis associated withcondEventA3,condEventA4orcondEventA5, and if the leaving condition(s) applicable for this event associated with thecondReconfigId, i.e. the event corresponding with thecondEventId(s)of the correspondingcondTriggerConfigwithinVarConditionalReconfig, is fulfilled for the applicable cells for all measurements after layer 3 filtering taken during the correspondingtimeToTriggerdefined for this event within theVarConditionalReconfig:

[0228] 5> consider the event associated to thatmeasIdto be not fulfilled;

[0229] 3> else:

[0230] 4> if NES mode indication is received from lower layers, indicating that the NES-specific CHO execution condition of the PCell is enabled; and

[0231] 4> if the entry condition(s) applicable for this event associated with thecondReconfigId, i.e. the event corresponding with thecondEventId(s)of the correspondingcondTriggerConfigwithinVarConditionalReconfig, is fulfilled for the applicable cells for all measurements after layer 3 filtering taken during the correspondingtimeToTriggerdefined for this event within theVarConditionalReconfig:

[0232] 5> consider the event associated to thatmeasIdto be fulfilled;

[0233] 4> if themeasIdfor this event associated with thecondReconfigIdhas been modified; or

[0234] 4> if NES mode indication is received from lower layers, indicating that the NES-specific CHO execution condition of the PCell is disabled; or

[0235] 4> if the leaving condition(s) applicable for this event associated with thecondReconfigId, i.e. the event corresponding with thecondEventId(s)of the correspondingcondTriggerConfigwithinVarConditionalReconfig, is fulfilled for the applicable cells for all measurements after layer 3 filtering taken during the correspondingtimeToTriggerdefined for this event within theVarConditionalReconfig:

[0236] 5> consider the event associated to thatmeasIdto be not fulfilled;

[0237] 2> ifcondExecutionCondPSCellis not configured:

[0238] 3> if event(s) associated to allmeasId(s) withincondTriggerConfigfor the applicable cell are fulfilled:

[0239] 4> consider the applicable cell, associated to thatcondReconfigId, as a triggered cell;

[0240] 4> initiate the conditional reconfiguration execution;

[0241] 2> else:

[0242] 3> if event(s) associated to allmeasId(s), as indicated in thecondExecutionCondandcondExecutionCondPSCell,withincondTriggerConfigfor a target candidate cell within the storedcondRRCReconfigare fulfilled:

[0243] 4> consider the target candidate PCell within the storedcondRRCReconfig, associated to thatcondReconfigId, as a triggered PCell;

[0244] 4> consider the target candidate PSCell within the storedcondRRCReconfig, associated to thatcondReconfigId, as a triggered PSCell;

[0245] 4> initiate the conditional reconfiguration execution;

[0246] 2> if one of the events associated to themeasIds withincondTriggerConfigfor the applicable cell within the storedcondRRCReconfigis not configured withnesEvent, and the other event associated to themeasIds withincondTriggerConfigfor the applicable cell within the storedcondRRCReconfigis configured withnesEvent, and at least one of them is fulfilled:

[0247] 3> consider the applicable cell within the storedcondRRCReconfig, associated to thatcondReconfigId, as a triggered cell;

[0248] 3> initiate the conditional reconfiguration execution.

[0249] Up to 2MeasIdcan be configured for eachcondReconfigId, ifcondExecutionCondPSCellis not configured.The conditional reconfiguration event of the 2MeasIdmay have the same or different event conditions, triggering quantity, time to trigger, and triggering threshold.

[0250] For CHO with candidate SCG(s), up to 2MeasIdcan be configured forcondExecutionCondandup to 2MeasIdcan be configured forcondExecutionCondPSCellfor eachcondReconfigId.

[0251] III. Conditional reconfiguration execution

[0252] The UE shall:

[0253] 1> if more than one pair of triggered PCell and associated triggered PSCell exist:

[0254] 2> select one of the triggered PCell(s) and the associated triggered PSCell(s) as the selected cells for conditional reconfiguration execution;

[0255] 1> else if only one pair of triggered PCell and associated triggered PSCell exists:

[0256] 2> consider the triggered PCell and the associated triggered PSCell as the selected cells for conditional reconfiguration execution;

[0257] 1> else if more than one triggered cell exists:

[0258] 2> select one of the triggered cells as the selected cell for conditional reconfiguration execution;

[0259] 1> else:

[0260] 2> consider the triggered cell as the selected cell for conditional reconfiguration execution;

[0261] 1> for the selected cell(s) of conditional reconfiguration execution:

[0262] 2> if thesubsequentCondReconfigis included in the entry inVarConditionalReconfigcontaining theRRCReconfigurationmessage for the selected cell:

[0263] 3> perform the subsequent CPAC execution;

[0264] 2> else:

[0265] 3> apply the storedcondRRCReconfigof the selected cell and perform the actions upon receiving / applying theRRCReconfigurationmessage in thecondRRCReconfig(i.e., perform a mobility to the corresponding SpCell / target cell based on theRRCReconfigurationmessage in thecondRRCReconfig).

[0266] If multiple NR cells are triggered in conditional reconfiguration execution, it is up to UE implementation which one to select, e.g. the UE considers beams and beam quality to select one of the triggered cells for execution.

[0267] IV. Subsequent CPAC execution

[0268] Upon the conditional reconfiguration execution for subsequent CPAC, the UE shall:

[0269] 1> if the selected subsequent CPAC candidate configuration is stored in MCGVarConditionalReconfig:

[0270] 2> for each SRB / DRB in current UE configuration:

[0271] - keep the associated RLC, PDCP and SDAP entities, their state variables, buffers and timers;

[0272] - release all fields related to the SRB / DRB configuration except forsrb-Identity,drb-Identity, andsecurityConfig;

[0273] 2> release / clear all current dedicated radio configuration except for the following:

[0274] - the MCG C-RNTI;

[0275] - the AS security configurations associated with the master key and the secondary key;

[0276] - thelogicalChannelIdentityandlogicalChannelIdentityExtof RLC bearers configured in RLC-BearerConfig and the associated RLC entities, their state variables, buffers, and timers;

[0277] - the bh-LogicalChannelIdentityof BH RLC channels configured inBH-RLC-ChannelConfigand the associated RLC entities, their state variables, buffers, and timers;

[0278] - the UE variablesVarConditionalReconfigandVarServingSecurityCellSetID;

[0279] - the logged measurement configuration.

[0280] 2> release / clear all current common radio configuration, except for theServingCellConfigCommonof the PCell;

[0281] 2> apply the default MAC Cell Group configuration for MCG MAC and SCG MAC;

[0282] 2> use the default values for timers T310, T311 and constants N310, N311, where T310, N310, and N311 are for both MCG and SCG, and T311 is only for the MCG;

[0283] 2> apply the default L1 parameter values as specified in corresponding physical layer specifications for the MCG and SCG;

[0284] 1> else:

[0285] 2> for each SRB / DRB in current UE configuration:

[0286] - keep the associated PDCP and SDAP entities, their state variables, buffers and timers;

[0287] - release all fields related to the SRB / DRB configuration except forsrb-Identity,drb-Identity, andsecurityConfig;

[0288] 2> release / clear all current dedicated radio configuration associated with the SCG except for the following:

[0289] - the AS security configurations associated with the secondary key;

[0290] - the UE variablesVarConditionalReconfig.

[0291] 2> release / clear all current common radio configuration associated with the SCG;

[0292] 2> apply the default MAC Cell Group configuration for the SCG MAC;

[0293] 2> use the default values for timer T310 and constants N310 and N311 for the SCG;

[0294] 2> apply the default L1 parameter values as specified in corresponding physical layer specifications for the SCG;

[0295] 1> if thesecurityCellSetIdis included in the entry inVarConditionalReconfigcontaining theRRCReconfigurationmessage:

[0296] 2> ifservingSecurityCellSetIdis not included withinVarServingSecurityCellSetID; or

[0297] 2> if the value of thesecurityCellSetIdis not equal to the value ofservingSecurityCellSetIdwithinVarServingSecurityCellSetID:

[0298] 3> consider the firstsk-Countervalue in thesk-CounterListassociated with thesecurityCellSetIdwithin theVarConditionalReconfigas the selectedsk-Countervalue, and perform security key update procedure;

[0299] 3> remove the selectedsk-Countervalue from thesk-CounterListassociated with thesecurityCellSetIdwithin theVarConditionalReconfig;

[0300] 3> if the currentVarServingSecurityCellSetIDincludesservingSecurityCellSetId:

[0301] 4> replace the value ofservingSecurityCellSetIdwithinVarServingSecurityCellSetIDwith the value ofsecurityCellSetIdassociated with the selected cell;

[0302] 3> else:

[0303] 4> store theservingSecurityCellSetIdwithinVarServingSecurityCellSetIDwith the value ofsecurityCellSetIdassociated with the selected cell;

[0304] 1> if the selected subsequent CPAC candidate configuration is stored in the SCGVarConditionalReconfig:

[0305] 2> for eachdrb-Identityvalue included in eachRadioBearerConfigin the selected subsequent CPAC candidate configuration that is part of the current UE configuration, the UE shall perform the following actions after the end of this procedure:

[0306] 3> if the bearer is an AM DRB:

[0307] 4> trigger the PDCP entity of the bearer to perform PDCP data recovery;

[0308] 3> re-establish the corresponding RLC entity;

[0309] 1> else:

[0310] 2> for eachdrb-Identityvalue included in eachRadioBearerConfigin the selected subsequent CPAC candidate configuration that is part of the current UE configuration, the UE shall perform the following actions after the end of this procedure:

[0311] 3> if thekeyToUsein theRadioBearerConfigis different from thekeyToUsein the current UE configuration; or

[0312] 3> if the bearer is associated with the secondary key (S-KgNB) as indicated bykeyToUsein the current UE configuration and a newsk-Countervalue has been selected due to the conditional reconfiguration execution for subsequent CPAC:

[0313] 4> if the PDCP entity of this DRB is not configured withcipheringDisabled:

[0314] 5> configure the PDCP entity with the ciphering algorithm and KUPenc key associated with the master key (KgNB) or the secondary key (S-KgNB), as indicated inkeyToUse, i.e., the ciphering configuration shall be applied to all subsequent PDCP PDUs received and sent by the UE;

[0315] 4> if the PDCP entity of this DRB is configured withintegrityProtection:

[0316] 5> configure the PDCP entity with the integrity protection algorithms according tosecurityConfigand apply the KUPint key associated with the master key (KgNB) or the secondary key (S-KgNB) as indicated inkeyToUse;

[0317] 4> ifdrb-ContinueROHCis included inpdcp-Config:

[0318] 5> indicate to lower layer thatdrb-ContinueROHCis configured;

[0319] 4> ifdrb-ContinueEHC-DLis included inpdcp-Config:

[0320] 5> indicate to lower layer thatdrb-ContinueEHC-DLis configured;

[0321] 4> ifdrb-ContinueEHC-ULis included inpdcp-Config:

[0322] 5> indicate to lower layer thatdrb-ContinueEHC-ULis configured;

[0323] 4> ifdrb-ContinueUDCis included inpdcp-Config:

[0324] 5> indicate to lower layer thatdrb-ContinueUDCis configured;

[0325] 4> re-establish the corresponding RLC entity;

[0326] 4> trigger the PDCP entity of the bearer to perform PDCP re-establishment;

[0327] 3> else:

[0328] 4> if there is an associated SCG RLC bearer in the selected subsequent CPAC candidate configuration that is part of the current UE configuration:

[0329] 5> re-establish the SCG RLC entity;

[0330] 4> if the RLC entity of the associated RLC bearer(s) is re-established; or

[0331] 4> if an associated RLC bearer is released in the selected subsequent CPAC candidate configuration:

[0332] 5> if the bearer is an AM DRB:

[0333] 6> trigger the PDCP entity of the bearer to perform PDCP data recovery;

[0334] 2> for eachsrb-Identityincluded inRadioBearerConfigthat is part of the current UE configuration and if the radio bearer is SRB3 or SRB5, the UE shall perform the following actions after the end of this procedure:

[0335] 3> if a newsk-Countervalue has been selected due to the conditional reconfiguration execution for subsequent CPAC:

[0336] 4> configure the PDCP entity to apply the integrity protection algorithm and KRRCint key associated with the secondary key (S-KgNB) as indicated inkeyToUse, i.e. the integrity protection configuration shall be applied to all subsequent messages received and sent by the UE, including the message used to indicate the successful completion of the procedure;

[0337] 4> configure the PDCP entity to apply the ciphering algorithm and KRRCenc key associated with the secondary key (S-KgNB) as indicated inkeyToUse, i.e. the ciphering configuration shall be applied to all subsequent messages received and sent by the UE, including the message used to indicate the successful completion of the procedure;

[0338] 4> trigger the PDCP entity of SRB to perform PDCP re-establishment;

[0339] 3> else:

[0340] 4> trigger the PDCP entity of SRB to perform SDU discard;

[0341] 3> re-establish the corresponding RLC entity;

[0342] 1> ifscpac-ConfigCompleteis not included within theVarConditionalReconfigfor the selected cell:

[0343] 2> if the subsequent CPAC candidate cell configuration is stored in MCGVarConditionalReconfig:

[0344] 3> considerscpac-ReferenceConfigurationin MCGVarConditionalReconfigto be the current UE configuration;

[0345] 2> else:

[0346] 3> considerscpac-ReferenceConfigurationin SCGVarConditionalReconfigto be the current SCG configuration;

[0347] When the UE considers the reference configuration to be the current UE configuration, the UE should store fields and configurations that are part of the reference configuration but should not execute any actions or procedures triggered by the reception of anRRCReconfigurationmessage.

[0348] 1> apply the storedcondRRCReconfigof the selected cell(s) and perform the actions upon receiving / applying theRRCReconfigurationmessage in thecondRRCReconfig(i.e., perform a mobility to the corresponding SpCell / target cell based on theRRCReconfigurationmessage in thecondRRCReconfig);

[0349] 1> release the radio bearer(s) and the associated logical channel(s) that are part of the current UE configuration but not part of the subsequent CPAC candidate configuration for the selected cell, or the subsequent CPAC reference configuration (in case the subsequent CPAC candidate configuration does not includescpac-ConfigComplete).

[0350] Whenscpac-ConfigCompleteis not included for the selected cell, before a subsequent CPAC execution, a UE implementation may generate and store an RRC reconfiguration message by applying the received subsequent CPAC candidate configuration on top of the subsequent CPAC reference configuration, and the stored RRC reconfiguration message is applied for subsequent CPAC execution. The UE needs to ensure that the RRC reconfiguration applied at the time of subsequent CPAC execution is in accordance with the latest receivedscpac-ReferenceConfigurationandcondRRCReconfigfor the subsequent CPAC configuration.

[0351] Hereinafter, radio link failure (RLF) related actions are described.

[0352] FIG. 9 shows an example of an RLF report procedure.

[0353] Referring to FIG. 9, in step S901, UE may detect a failure (e.g., RLF, mobility failure) on a master cell group (MCG).

[0354] For example, the UE may monitor a radio link quality of a primary cell (PCell). Upon receiving　N310　consecutive 'out-of-sync' indications from the physical layer, the UE may start a　T310　timer. If the link is not recovered before the　T310　expires, or if a random access problem is indicated by the MAC layer, or if the RLC layer reaches the maximum number of retransmissions, the UE may declare / detect an RLF.

[0355] For example, upon initiating a mobility procedure (i.e., upon applyingRRCReconfigurationincludingReconfigurationWithSyncfor a corresponding mobility target cell), the UE may start a　T304　timer or a　T312　timer. If the UE fails to successfully complete the random access procedure toward the target cell before the timer expires, the UE may declare / detect a　mobility failure.

[0356] In step S903, the UE may log failure-related information. After detecting a failure (e.g., RLF, mobility failure), the UE may log failure-related information comprising at least one of RLF information or mobility failure information.

[0357] For example, in case of RLF, the UE may log the RLF information comprising at least one of the identity of the last serving cell, the cause of the failure (e.g.,　t310-Expiry,　randomAccessProblem), the radio measurement results (e.g.,　RSRP,　RSRQ, and　SINR) of the serving cell or available neighboring cells at the time of failure.

[0358] For example, in case of mobility failure, the UE may log the mobility failure information comprising at least one of the identity of the target cell (the cell where the handover failed), the signal strength of both the source and target cells, or the elapsed time since the failure occurred.

[0359] The failure-related information may further comprise at least one of geographical location information (if available) or a time-stamp indicating when the failure occurred.

[0360] The transmission of the RLF report is initiated after the UE successfully re-establishes a connection with the network and / or establishes a new RRC connection in a suitable cell.

[0361] In step S905, the UE may transmit an availability notification to network. During the RRC connection completion procedure, the UE may transmit a specific indicator (e.g.,rlf-InfoAvailable) set to 'true' via an　RRCSetupComplete,RRCResumeComplete, or　RRCReestablishmentComplete　message. The indicator may notify the network that the UE has a logged RLF report containing the RLF information and / or mobility failure information.

[0362] In step S907, the UE may receive a request to provide the RLF report from network. Upon identifying the availability of the RLF report, the network may transmit a　UEInformationRequestmessageto the UE. Within this message, the　rlf-ReportReq　field is set to 'true' to explicitly command the UE to provide the RLF report.

[0363] In response, in step S909, the UE may transmit the RLF report to network. The UE may transmit a　UEInformationResponse　message. This message may include the　rlf-Report　container, which encapsulates the logged　mobility failure information　(e.g.,　failedPCellId,　measResultLastServCell) and / or　radio link failure information.

[0364] In step S911, after a successful confirmation of the delivery of the　UEInformationResponse, the UE may discard the reported failure-related information.

[0365] Hereinafter, actions related to reporting SCG failure information are described.

[0366] UE in a Multi-Radio Dual Connectivity (MR-DC) environment may detect a failure in a Secondary Cell Group (SCG) and report the failure information to a Master Node (MN).

[0367] FIG. 10 shows an example of SCG failure information procedure.

[0368] Referring to FIG. 10, in step S1001, the UE may detect a failure on a secondary cell group (SCG). The failure may comprise at least one of SCG RLF, PSCell addition / change failure, or SCG configuration failure.

[0369] For example, the UE may detect / declare an SCG RLF when (i) a　T310　timer started for a Primary Secondary Cell (PSCell) expires, (ii) the SCG MAC layer indicates a random access problem, or (iii) the SCG RLC layer indicates that the maximum number of retransmissions has been reached.

[0370] For example, the UE may detect / declare PSCell addition / change failure when a　T304　timer, which is started upon initiating the PSCell addition / change (i.e., upon applyingRRCReconfigurationincludingReconfigurationWithSyncfor the SCG / target PSCell), expires before the successful completion of the random access procedure toward the target PSCell.

[0371] For example, the UE may detect the SCG configuration failure when a reconfiguration failure occurs for the SCG or when an integrity check failure is indicated by the SCG SRB3.

[0372] In step S1003, the UE may initiate the SCG failure information procedure to inform the network of the detected failure while maintaining the connection to the MCG. For example, UE may initiate the SCG failure information procedure to report SCG failures when neither MCG nor SCG transmission is suspended and when at least one of the following conditions is met:

[0373] - upon detecting radio link failure for the SCG;

[0374] - upon detecting beam failure of the PSCell while the SCG is deactivated;

[0375] - upon reconfiguration with sync failure of the SCG;

[0376] - upon SCG configuration failure; and / or

[0377] - upon integrity check failure indication from SCG lower layers concerning SRB3.

[0378] If the MCG connection is also lost, the UE may initiate an RRC Connection Re-establishment procedure instead of the SCG failure information procedure.

[0379] In step S1005, upon initiating the SCG failure information procedure, the UE may set the contents of the　SCGFailureInformation　message. For example, theSCGFailureInformation　message comprises at least one of:

[0380] - Failure Type information:　the UE may set the　failureType　field to the specific cause of the failure, such as　t310-Expiry,　randomAccessProblem,　rlc-MaxNumRetx, or　scg-reconfigFailure.

[0381] - Measurement Results:　the UE may include measurement results of the SCG and neighboring frequencies in the　measResultFreqListMRDC　field. This includes　RSRP,　RSRQ, and　SINR　values of the failed PSCell and candidate cells to assist the Master Node to recover the SCG failure.

[0382] - Location Information:　If available, the UE may include geographical coordinates to assist the network in identifying coverage holes in the SCG deployment.

[0383] In step S1007, the UE may transmit the　SCGFailureInformation　message to the Master Node (MN) via the　MCG SRB1 (Signaling Radio Bearer 1). Even if an SRB3 was established for the SCG, the failure report (e.g.,SCGFailureInformation　message) is routed through the MCG to ensure reliable delivery during SCG instability.

[0384] Immediately after or during the transmission of theSCGFailureInformation　message, the UE may suspend all SCG transmissions. However, the UE does not reset the SCG MAC or release the SCG configuration, but rather waits for an　RRCReconfiguration　message from the Master Node to either release, reset, or reconfigure the SCG.

[0385] Meanwhile, mobility mechanisms such as Conditional Handover (CHO) and Conditional PSCell Addition / Change (CPAC) allow a user equipment (UE) to evaluate pre-configured execution conditions before initiating mobility procedures. Further, the UE is allowed to evaluate and / or initiate CHO and associated CPAC simultaneously by the network configuration. In the present disclosure, the expression　'CHO and associated CPAC'　refers to a combination of　CHO to a PCell　and　CPAC (or PSCell mobility) to an associated PSCell, and may be interchangeably referred to as　'CHO+CPAC'.

[0386] While evaluating CHO and associated CPAC execution conditions, if a Radio Link Failure (RLF) occurs in Master Cell Group (MCG) and / or Secondary Cell Group (SCG), the UE logs CHO and the associated CPAC condition evaluation results (i.e., CHO+CPAC evaluation results). Specifically, the UE may include the following information in the RLF report:

[0387] - Whether CHO and / or CPAC conditions were satisfied;

[0388] - Which condition was first met among the CHO and the associated CPAC conditions;

[0389] - The time gap between a time of fulfilling the CHO execution condition and a time of fulfilling the CPAC execution condition (when both of the CHO execution condition and the CPAC execution condition were fulfilled); and / or

[0390] - The time elapsed from a time when whichever of the CHO execution condition and the CPAC execution condition is first satisfied, to the RLF occurrence.

[0391] Also, when SCG RLF occurs, the UE may log the above information in the SCG failure information.

[0392] A problem is when both MCG RLF and SCG RLF occur in succession while the UE is evaluating CHO+CPAC execution conditions. In such a case, the same CHO+CPAC condition evaluation results may be logged redundantly in both RLF-report and SCG failure information, leading to duplicate reporting to the network. As a result, this redundancy can cause incorrect mobility optimizations by the network since the same evaluation results are logged in two different reports and forwarded to the network at different times, and the network may mistakenly treat the same logged data as two separate samples. Then, the network may misinterpret the reported execution conditions and may optimize inappropriate CHO+CPAC execution conditions for similar UEs. This could lead to incorrect mobility timing, causing issues such as too early handover / mobility, resulting in RLF at the target cell and / or unnecessary mobilities / handovers, increasing signaling overhead and / or UE power consumption.

[0393] For example, when SCG RLF occurs, UE may log CHO+CPAC evaluation results in SCG failure information. UE may send the SCG failure information to the source Master Node (MN). Source MN may receive the logging information (e.g., CHO+CPAC evaluation results) via the SCG failure information, as the first log sample.

[0394] Then, MCG RLF may occur, and the UE may log the same CHO+CPAC evaluation results in RLF-report. After RRC Re-establishment, the new PCell (possibly a new MN) receives the RLF-report and forwards it to the source MN. Source MN receives the same logging information (e.g., CHO+CPAC evaluation results) via the RLF-report from the new MN, as the second log sample.

[0395] Since there may be a time gap between the two logs, the network may not recognize them as the same report, leading to an erroneous parameter adjustment.

[0396] Therefore, the present disclosure provides various embodiments for failure information reporting in conditional mobility.

[0397] FIG. 11 shows an example of a method performed by a UE for failure information reporting in conditional mobility according to various embodiments of the present disclosure.

[0398] Referring to FIG. 11, in step S1101, the UE may receive a conditional reconfiguration comprising execution conditions including: one or more execution conditions for CHO for a candidate PCell; and one or more execution conditions for PSCell mobility for a candidate PSCell related to the candidate PCell.

[0399] In step S1103, the UE may evaluate the one or more execution conditions for CHO and the one or more execution conditions for PSCell mobility.

[0400] In step S1105, based on detecting a failure related to an MCG, the UE may transmit an RLF report comprising one or more first evaluation results among evaluation results of the execution conditions.

[0401] In step S1107, based on detecting a failure related to an SCG, the UE may transmit SCG failure information comprising one or more second evaluation results among the evaluation results of the execution conditions.

[0402] The order in which steps S1105 and S1107 are performed　may be changed. That is, these two steps　may be performed concurrently, or step S1107　may be performed prior to　step S1105.

[0403] According to various embodiments, the failure related to the MCG may comprise at least one of a radio link failure (RLF) on the MCG, or a failure of the CHO. The failure related to the SCG may comprise at least one of an RLF on the SCG or a failure of the PSCell mobility.

[0404] According to various embodiments, the conditional reconfiguration may comprise a configuration of the candidate PCell. The configuration of the candidate PCell may comprise an SCG configuration. The SCG configuration may comprise a configuration of the candidate PSCell related to the candidate PCell.

[0405] According to various embodiments, the UE may perform a mobility based on both of i) the one or more execution conditions for CHO and ii) the one or more execution conditions for PSCell mobility being fulfilled. The mobility may comprise at least one of CHO to the candidate PCell, or PSCell mobility to the candidate PSCell.

[0406] According to various embodiments, the one or more first evaluation results may comprise at least one of: at least part of evaluation results of the one or more execution conditions for CHO; or at least part of evaluation results of the one or more execution conditions for PSCell mobility. The one or more second evaluation results may comprise at least one of: remaining part of the evaluation results of the one or more execution conditions for CHO; or remaining part of the evaluation results of the one or more execution conditions for PSCell mobility.

[0407] According to various embodiments, the evaluation results of the one or more execution conditions for CHO may comprise at least one of: information for whether the one or more execution conditions for CHO are fulfilled; information for whether the one or more execution conditions for CHO are fulfilled first among the execution conditions; information for an elapsed time between fulfillments of the one or more execution conditions for CHO and the one or more execution conditions for PSCell mobility; information for an elapsed time between a point in time of fulfilling the one or more execution conditions for CHO and the failure related to the MCG; information for an execution condition that is fulfilled first among the one or more execution conditions for CHO; or information for an elapsed time between points in time of fulfilling the one or more execution conditions for CHO.

[0408] According to various embodiments, the evaluation results of the one or more execution conditions for PSCell mobility may comprise at least one of: information for whether the one or more execution conditions for PSCell mobility are fulfilled; information for whether the one or more execution conditions for PSCell mobility are fulfilled first among the execution conditions; information for an elapsed time between fulfillments of the one or more execution conditions for CHO and the one or more execution conditions for PSCell mobility; information for an elapsed time between a point in time of fulfilling the one or more execution conditions for PSCell mobility and the failure related to the SCG; information for an execution condition that is fulfilled first among the one or more execution conditions for PSCell mobility; or information for an elapsed time between points in time of fulfilling the one or more execution conditions for PSCell mobility.

[0409] According to various embodiments, the RLF report may exclude the one or more second evaluation results. The SCG failure information may exclude the one or more first evaluation results.

[0410] According to various embodiments, the UE may discard the one or more first evaluation results based on logging the one or more first evaluation results in the RLF report. The UE may discard the one or more second evaluation results based on logging the one or more second evaluation results in the SCG failure information.

[0411] According to various embodiments, the one or more first evaluation results may comprise the evaluation results of the one or more execution conditions for CHO. The one or more second evaluation results may comprise the evaluation results of the one or more execution conditions for PSCell mobility.

[0412] According to various embodiments, each of the RLF report and the SCG failure information may comprise: both of the evaluation results of the one or more execution conditions for CHO and the evaluation results of the one or more execution conditions for PSCell mobility; and information informing that both of the RLF report and the SCG failure information comprise same evaluation results.

[0413] According to various embodiments, the PSCell mobility may comprise at least one of a PSCell change to the candidate PSCell, or PSCell addition of the candidate PSCell.

[0414] FIG. 12 shows an example of a signal flow between UE and network node for failure information reporting in conditional mobility according to various embodiments of the present disclosure.

[0415] Referring to FIG. 12, in step S1201, the network node may transmit, to the UE a conditional reconfiguration comprising execution conditions including: one or more execution conditions for CHO for a candidate PCell; and one or more execution conditions for PSCell mobility for a candidate PSCell related to the candidate PCell.

[0416] In step S1203, the UE may evaluate the one or more execution conditions for CHO and the one or more execution conditions for PSCell mobility.

[0417] In step S1205, the network node may receive, from the UE, an RLF report comprising one or more first evaluation results among evaluation results of the execution conditions, based on an occurrence of a failure related to an MCG.

[0418] In step S1207, the network node may receive, from the UE, SCG failure information comprising one or more second evaluation results among the evaluation results of the execution conditions, based on an occurrence of a failure related to an SCG.

[0419] The order in which steps S1205 and S1207 are performed　may be changed. That is, these two steps　may be performed concurrently, or step S1207　may be performed prior to　step S1205.

[0420] Hereinafter, detailed descriptions regarding failure information reporting in conditional mobility are described.

[0421] According to various embodiments, while evaluating one or more execution conditions for CHO and associated CPAC, to prevent duplicate logging and / or incorrect sampling, the UE may perform at least one of the below UE behaviours when MCG RLF and / or SCG RLF is detected.

[0422] In some implementations, the UE may check if the same results of the CHO and / or associated CPAC evaluation has been reported before. If the same results of the CHO and / or associated CPAC evaluation has been reported in SCG failure information, the UE may exclude the results of the CHO and / or associated CPAC evaluation when the UE logs mobility information in MCG RLF report. If the same results of the CHO and associated CPAC evaluation has been reported in MCG RLF report, the UE may exclude the results of the CHO and / or associated CPAC evaluation when the UE logs mobility information in SCG failure information.

[0423] In some implementations, the UE may remove the CHO and associated CPAC evaluation results as soon as the CHO and associated CPAC evaluation results are logged in any report message. That is, the UE may discard the results of the CHO and associated CPAC evaluation once the UE logs the results of the CHO and associated CPAC evaluation in any report message, i.e., among MCG RLF-report and SCG failure information.

[0424] In some implementations, the UE may selectively log CHO+CPAC evaluation results based on the failure domain. For example, MCG RLF-report may include only MCG specific results, i.e., CHO-related evaluation results, comprising at least one of: CHO condition fulfillment / evaluation status; whether CHO execution condition was first fulfilled among the CHO execution condition and associated CPAC execution condition; or a time gap between a time of fulfilling the CHO execution condition and MCG RLF. For example, SCG failure information may include only SCG specific results, i.e., CPAC-related evaluation results, comprising at least one of: CPAC condition fulfillment / evaluation status; whether CPAC execution condition was first fulfilled among the CHO execution condition and associated CPAC execution condition; or a time gap between a time of fulfilling the CPAC execution condition and SCG RLF. For example, for both reports, an identifier may be included to indicate that the reports include the same CHO+CPAC evaluation results, preventing redundant log sampling by the network.

[0425] The UE shall determine the content in the RLF report (i.e.,VarRLF-Report) as follows:

[0426] 1> clear the information included inVarRLF-Report, if any;

[0427] 1> if the UE is not in SNPN access mode, set theplmn-IdentityListto include the list of EPLMNs stored by the UE (i.e. including the RPLMN);

[0428] 1> else if the UE is in SNPN access mode, set thesnpn-IdentityListto include the list of equivalent SNPNs stored by the UE (i.e., including the registered SNPN identity);

[0429] 1> set themeasResultLastServCellto include the cell level RSRP, RSRQ and the available SINR, of the source PCell (in case HO failure) or PCell (in case RLF) based on the available SSB and CSI-RS measurements collected up to the moment the UE detected failure;

[0430] 1> if the UE supports RLF-Report for conditional handover with candidate SCG and if the UE was configured withcondExecutionCondandcondExecutionCondPSCell;

[0431] 2> set themeasResultLastServPSCellto include the cell level RSRP, RSRQ and the available SINR, of the source PSCell (in case of PSCell change) or PSCell (in case of no PSCell change) based on the available SSB and CSI-RS measurements collected up to the moment the UE detected the failure;

[0432] 2> if the UE does not support RLF-Report for fast MCG recovery procedure or if T316 is not configured:

[0433] 3> setpSCellIdto the global cell identity and tracking area code, if available, and otherwise the physical cell identity and carrier frequency of the source PSCell (in case of PSCell change) or PSCell (in case of no PSCell change);

[0434] 1> if the UE supports RLF-Report for conditional handover with time-based or location-based trigger condition and if one entry ofchoConfigconcernscondEventD2;

[0435] 2> setdistanceFromReference1to the measured distance between the UE and the serving cell moving reference location;

[0436] 1> ifmeasRSSI-ReportConfigis configured for themeasObjectindicated as theservingCellMOof the source PCell (in case HO failure) or PCell (in case of RLF), set themeasResultLastServCellRSSIto the linear average of the available RSSI sample value(s) provided by lower layers for the frequency of the source PCell (in case HO failure) or PCell (in case of RLF) up to the moment the UE detected the failure;

[0437] 1> if the SS / PBCH block-based measurement quantities are available:

[0438] 2> set thersIndexResultsinmeasResultLastServCellto include all the available measurement quantities of the source PCell (in case HO failure) or PCell (in case RLF), ordered such that the highest SS / PBCH block RSRP is listed first if SS / PBCH block RSRP measurement results are available, otherwise the highest SS / PBCH block RSRQ is listed first if SS / PBCH block RSRQ measurement results are available, otherwise the highest SS / PBCH block SINR is listed first, based on the available SS / PBCH block based measurements collected up to the moment the UE detected failure;

[0439] 2> if the UE supports RLF-Report for conditional handover with candidate SCG and if the UE was configured withcondExecutionCondandcondExecutionCondPSCell:

[0440] 3> set thersIndexResultsinmeasResultLastServPSCellto include all the available measurement quantities of the source PSCell (in case of PSCell change) or PSCell (in case of no PSCell change) if the UE was configured withcondExecutionCondandcondExecutionCondPSCell, ordered such that the highest SS / PBCH block RSRP is listed first if SS / PBCH block RSRP measurement results are available, otherwise the highest SS / PBCH block RSRQ is listed first if SS / PBCH block RSRQ measurement results are available, otherwise the highest SS / PBCH block SINR is listed first, based on the available SS / PBCH block based measurements collected up to the moment the UE detected failure;

[0441] 1> if the CSI-RS based measurement quantities are available:

[0442] 2> set thersIndexResultsinmeasResultLastServCellto include all the available measurement quantities of the source PCell (in case HO failure) or PCell (in case RLF), ordered such that the highest CSI-RS RSRP is listed first if CSI-RS RSRP measurement results are available, otherwise the highest CSI-RS RSRQ is listed first if CSI-RS RSRQ measurement results are available, otherwise the highest CSI-RS SINR is listed first, based on the available CSI-RS based measurements collected up to the moment the UE detected failure;

[0443] 2> if the UE supports RLF-Report for conditional handover with candidate SCG and if the UE was configured withcondExecutionCondandcondExecutionCondPSCell:

[0444] 3> set thersIndexResultsinmeasResultLastServPSCellto include all the available measurement quantities of the source PSCell (in case of PSCell change) or PSCell (in case of no PSCell change), ordered such that the highest CSI-RS RSRP is listed first if CSI-RS RSRP measurement results are available, otherwise the highest CSI-RS RSRQ is listed first if CSI-RS RSRQ measurement results are available, otherwise the highest CSI-RS SINR is listed first, based on the available CSI-RS based measurements collected up to the moment the UE detected failure;

[0445] 1> if the UE supports RLF-Report for MCG LTM cell switch and if the UE was configured withltm-Configassociated with the MCG when connected to the source PCell (in case of HO failure) or PCell (in case of RLF) and if the SS / PBCH block-based L1-RSRP measurements performed based onLTM-CSI-ReportConfigare available:

[0446] 2> set theresultsSSB-IndexesinmeasResultL1-LastServCellto include all the available SS / PBCH block-based L1-RSRP values of the source PCell (in case HO failure) or PCell (in case RLF), ordered such that the highest SS / PBCH block L1-RSRP measurement is listed first, based on the available SS / PBCH block-based L1-RSRP collected up to the moment the UE detected failure;

[0447] 1> for each of the configuredmeasObjectNRin which measurements are available or in which the associatedreportConfigNRis configured as conditional handover with time-based or location-based trigger condition:

[0448] 2> if the SS / PBCH block-based measurement quantities are available:

[0449] 3> set themeasResultListNRinmeasResultNeighCellsto include all the available measurement quantities of the best measured cells, other than the source PCell (in case HO failure) or PCell (in case RLF) and other than the source PSCell (in case of PSCell change) or PSCell (in case of no PSCell change) if the UE was configured withcondExecutionCondandcondExecutionCondPSCelland if the UE supports RLF-Report for conditional handover with candidate SCG, ordered such that the cell with highest SS / PBCH block RSRP is listed first if SS / PBCH block RSRP measurement results are available, otherwise the cell with highest SS / PBCH block RSRQ is listed first if SS / PBCH block RSRQ measurement results are available, otherwise the cell with highest SS / PBCH block SINR is listed first, based on the available SS / PBCH block based measurements collected up to the moment the UE detected failure;

[0450] 3> for each neighbour cell included, include the optional fields that are available;

[0451] For the neighboring cells included inmeasResultListNRinmeasResultNeighCellsordered based on the SS / PBCH block measurement quantities, UE also includes the CSI-RS based measurement quantities, if available.

[0452] 2> if the CSI-RS based measurement quantities are available:

[0453] 3> set themeasResultListNRinmeasResultNeighCellsto include all the available measurement quantities of the best measured cells, other than the source PCell (in case HO failure) or PCell (in case RLF), and other than the source PSCell (in case of PSCell change) or PSCell (in case of no PSCell change) if the UE was configured withcondExecutionCondandcondExecutionCondPSCelland if the UE supports RLF-Report for conditional handover with candidate SCG, ordered such that the cell with highest CSI-RS RSRP is listed first if CSI-RS RSRP measurement results are available, otherwise the cell with highest CSI-RS RSRQ is listed first if CSI-RS RSRQ measurement results are available, otherwise the cell with highest CSI-RS SINR is listed first, based on the available CSI-RS based measurements collected up to the moment the UE detected radio link failure;

[0454] 3> for each neighbour cell included, include the optional fields that are available;

[0455] For ordering the neighboring cells based on the CSI-RS measurement quantities, UE includes measurements only for the cells not yet included inmeasResultListNRinmeasResultNeighCellsto avoid overriding SS / PBCH block-based ordered measurements.

[0456] 2> if measurement quantities are not available:

[0457] 3> setphysCellIdinmeasResultListNRinmeasResultNeighCellsto include the physical cell identity of the neighbour cells that are candidate cells for which thereconfigurationWithSyncis included in themasterCellGroupin the MCGVarConditionalReconfigat the moment of the detected failure;

[0458] 3> for each neighbour cell included, include the optional fields that are available;

[0459] 2> for each neighbour cell, if any, included inmeasResultListNRinmeasResultNeighCells:

[0460] 3> if the UE supports RLF-Report for conditional handover and if the neighbour cell is one of the candidate cells for which thereconfigurationWithSyncis included in themasterCellGroupin the MCGVarConditionalReconfigat the moment of the detected failure and if the related MCGVarConditionalReconfigonly concerns measurement-based trigger condition; or

[0461] 3> if the UE supports RLF-Report for conditional handover with time-based and location-based trigger conditions in NTN and if the neighbour cell is one of the candidate cells for which thereconfigurationWithSyncis included in themasterCellGroupin the MCGVarConditionalReconfigat the moment of the detected failure; or

[0462] 3> if the UE supports RLF-Report for conditional handover with candidate SCG and if the neighbour cell is one of the candidate cells for which thereconfigurationWithSyncis included in themasterCellGroupin the MCGVarConditionalReconfigat the moment of the detected failure:

[0463] 4> setchoConfiginMeasResult2NRto the execution condition for eachmeasIdwithincondTriggerConfigassociated to the neighbour cell within the MCGVarConditionalReconfig;

[0464] 4> if the first entry ofchoConfigcorresponds to a fulfilled execution condition at the moment of handover failure, or radio link failure; or

[0465] 4> if the second entry ofchoConfig, if available, corresponds to a fulfilled execution condition at the moment of handover failure, or radio link failure:

[0466] 5> setfirstTriggeredEventto the execution conditioncondFirstEventcorresponding to the first entry ofchoConfigor to the execution conditioncondSecondEventcorresponding to the second entry ofchoConfig, whichever execution condition was fulfilled first in time;

[0467] 5> settimeBetweenEventsto the elapsed time between the point in time of fulfilling the condition inchoConfigthat was fulfilled first in time, and the point in time of fulfilling the condition inchoConfigthat was fulfilled second in time, if both the first execution condition corresponding to the first entry and the second execution condition corresponding to the second entry in thechoConfigwere fulfilled;

[0468] 4> if the UE supports RLF-Report for conditional handover with time-based or location-based trigger condition and if one entry ofchoConfigconcernscondEventD2;

[0469] 5> setdistanceFromReference2to the measured distance between the UE and the moving reference location of the neighbour cell, at the moment of handover failure, or radio link failure;

[0470] 1> for each entry ofcondReconfigListin the MCGVarConditionalReconfigincluding bothcondExecutionCondandcondExecutionCondPSCell, include an entry incho-WithCandidateSCGInfoListand set the values as follows:

[0471] 2> if all triggering eventsof bothcondExecutionCondandcondExecutionCondPSCellof the concerned entry ofcondReconfigListare fulfilled:

[0472] 3> setfirstFulfilledConfigtochoifcondExecutionCondwas fulfilled first orcpcifcondExecutionCondPSCellwas fulfilled first;

[0473] 3> settimeBetweenFulfillmentto the elapsed time between the fulfillments of the last triggering events of the two execution conditions;

[0474] 2> else if all triggering eventsof only one of thecondExecutionCondorcondExecutionCondPSCellof the concerned entry ofcondReconfigListis fulfilled:

[0475] 3> setfirstFulfilledConfigtochoorcpc, whichever was fulfilled;

[0476] 3> settimeBetweenLastFulfillmentAndEventto the elapsed time between the point in time of fulfilling the last triggering event of the fulfilled execution condition and the RLF;

[0477] 2> set thepCellIdto the global cell identity and tracking area code, if available, and otherwise the physical cell identity and carrier frequency, of the target candidate PCell stored in thecondRRCReconfigof the concerned entry ofcondReconfigList;

[0478] 2> set thepsCellIdto the global cell identity and tracking area code, if available, and otherwise the physical cell identity and carrier frequency, of the target candidate PSCell stored in thecondRRCReconfigof the concerned entry ofcondReconfigList;

[0479] 2> if after receiving this CHO with candidate SCG configuration, the UE received a conditional handover configuration includingcondRRCReconfigfor the same target candidate PCell as set inpCellId:

[0480] 3> setfulfilledConfigWhenChoOnlytochoifcondExecutionCondwas fulfilled at the time of receiving the conditional handover configuration orcpcifcondExecutionCondPSCellwas fulfilled at the time of receiving the conditional handover configuration, otherwise setfulfilledConfigWhenChoOnlytoneither;

[0481] 1> if the UE supports RLF-Report for MCG LTM cell switch, for each neighbour MCG LTM candidate cell:

[0482] 2> if SS / PBCH block-based L1-RSRP measurement quantities performed based onLTM-CSI-ReportConfigare available:

[0483] 3> set themeasResultL1-NeighCellsto include all the available SS / PBCH block-based L1-RSRP measurement results, ordered such that the cell with highest SS / PBCH block-based L1-RSRP (of all SS / PBCH block-based L1-RSRP measurement results for the cell) is listed first;

[0484] 3> for each neighbour frequency included, include the optional fields that are available;

[0485] 1> for each of the configuredmeasObjectNRassociated with neighboring cellsif the associatedreportConfigNRincludesmeasRSSI-ReportConfig:

[0486] 2> set themeasResultNeighFreqRSSIin themeasResultNeighFreqListRSSIto the linear average of the available RSSI sample value(s) provided by lower layers for the frequencies other than the frequency of the source PCell (in case HO failure) or of the PCell (in case RLF), up to the moment the UE detected failure:

[0487] 3> for each neighbour frequency included, include the optional fields that are available;

[0488] 1> for each of the configured EUTRA frequencies in which measurements are available;

[0489] 2> set themeasResultListEUTRAinmeasResultNeighCellsto include the best measured cells ordered such that the cell with highest RSRP is listed first if RSRP measurement results are available, otherwise the cell with highest RSRQ is listed first, and based on measurements collected up to the moment the UE detected failure;

[0490] 3> for each neighbour cell included, include the optional fields that are available;

[0491] The measured quantities are filtered by the L3 filter as configured in the mobility measurement configuration. The measurements are based on the time domain measurement resource restriction, if configured. Exclude-listed cells are not required to be reported.

[0492] 1> set thec-RNTIto the C-RNTI used in the source PCell (in case HO failure) or PCell (in case RLF);

[0493] 1> if the failure is detected due to reconfiguration with sync failure as described in 5.3.5.8.3, set the fields inVarRLF-reportas follows:

[0494] 2> set theconnectionFailureTypetohof;

[0495] 2> if the UE supports RLF-Report for DAPS handover and if any DAPS bearer was configured while T304 was running:

[0496] 3> setlastHO-Typetodaps;

[0497] 3> if radio link failure was detected in the source PCell:

[0498] 4> settimeConnSourceDAPS-Failureto the time between the initiation of the DAPS handover execution and the radio link failure detected in the source PCell while T304 was running;

[0499] 4> set therlf-Causeto the trigger for detecting the source radio link failure;

[0500] 2> if the UE supports RLF-Report for conditional handover and if configuration of the conditional handover is available in the MCGVarConditionalReconfigat the moment of the handover failure:

[0501] 3> if the UE executed a conditional handover toward target PCell according to thecondRRCReconfigof the target PCell:

[0502] 4> settimeSinceCHO-Reconfigto the time elapsed between the execution of the lastRRCReconfigurationmessage includingreconfigurationWithSyncfor the target PCell of the failed conditional handover, and the reception in the source PCell of the lastconditionalReconfigurationincluding thecondRRCReconfigof the target PCell of the failed conditional handover;

[0503] 3> else:

[0504] 4> settimeSinceCHO-Reconfigto the time elapsed between the execution of the lastRRCReconfigurationmessage includingreconfigurationWithSyncfor the target PCell of the failed handover, and the reception in the source PCell of the lastconditionalReconfigurationincluding thecondRRCReconfig;

[0505] 3> setchoCandidateCellListto include the global cell identity, if available, and otherwise to the physical cell identity and carrier frequency of each of the candidate target cells for conditional handover included incondRRCReconfigwithin the MCGVarConditionalReconfigat the time of the failed handover, excluding the candidate target cells included inmeasResultNeighCells;

[0506] 2> if the UE supports RLF-Report for conditional handover and if the last executedRRCReconfigurationmessage includingreconfigurationWithSyncwas concerning a conditional handover:

[0507] 3> setlastHO-Typetocho;

[0508] 2> else if the UE supports RLF-Report for MCG LTM cell switch and the last executedRRCReconfigurationmessage includingreconfigurationWithSyncwas concerning an LTM cell switch:

[0509] 3> setlastHO-Typetoltm;

[0510] 2> if the UE supports RLF-Report for conditional handover with candidate SCG and if the last executedRRCReconfigurationmessage includingreconfigurationWithSyncwas concerning conditional handover with candidate SCG:

[0511] 3> setlastHO-TypetochoWithCandidateSCG;

[0512] 2> set thenrFailedPCellIdinfailedPCellIdto the global cell identity and tracking area code, if available, and otherwise to the physical cell identity and carrier frequency of the target PCell of the failed handover or a failed LTM cell switch;

[0513] 2> includenrPreviousCellinpreviousPCellIdand set it to the global cell identity and tracking area code of the PCell where the lastRRCReconfigurationmessage includingreconfigurationWithSyncwas applied;

[0514] 2> set thetimeConnFailureto the elapsed time since the execution of the lastRRCReconfigurationmessage including thereconfigurationWithSync;

[0515] 1> else if the failure is detected due to Mobility from NR failure, set the fields inVarRLF-reportas follows:

[0516] 2> set theconnectionFailureTypetohof;

[0517] 2> if lastMobilityFromNRCommandconcerned a failed inter-RAT handover from NR to E-UTRA and if the UE supports Radio Link Failure Report for Inter-RAT MRO EUTRA (NR to EUTRA):

[0518] 3> set theeutraFailedPCellIdinfailedPCellIdto the global cell identity and tracking area code, if available, and otherwise to the physical cell identity and carrier frequency of the target PCell of the failed handover;

[0519] 2> includenrPreviousCellinpreviousPCellIdand set it to the global cell identity and tracking area code of the PCell where the lastMobilityFromNRCommandmessage was received;

[0520] 2> set thetimeConnFailureto the elapsed time since the initialization of the handover associated to the lastMobilityFromNRCommandmessage;

[0521] 2> if the UE supports RLF report for inter-system handover for voice fallback and ifvoiceFallbackIndicationis included in the lastMobilityFromNRCommand:

[0522] 3> include the voiceFallbackHO;

[0523] 1> else if the failure is detected due to radio link failure, set the fields inVarRLF-reportas follows:

[0524] 2> set theconnectionFailureTypetorlf;

[0525] 2> set therlf-Causeto the trigger for detecting radio link failure;

[0526] 2> set thenrFailedPCellIdinfailedPCellIdto the global cell identity and the tracking area code, if available, and otherwise to the physical cell identity and carrier frequency of the PCell where radio link failure is detected;

[0527] 2> if anRRCReconfigurationmessage including thereconfigurationWithSyncwas received before the connection failure:

[0528] 3> if the last successfully executedRRCReconfigurationmessage including thereconfigurationWithSyncconcerned an intra NR handover or an LTM cell switch and the target cell of the intra NR handover or LTM cell switch was the PCell where radio link failure is detected; and

[0529] 3> if T316 was not running before entering the PCell in which the radio link failure was detected; and

[0530] 3> if T311 was not running before entering the PCell in which the radio link failure was detected:

[0531] 4> include thenrPreviousCellinpreviousPCellIdand set it to the global cell identity and the tracking area code of the source PCell of the intra NR handover or LTM cell switch concerning the last successfully executedRRCReconfigurationmessage includingreconfigurationWithSync;

[0532] 4> if the UE supports RLF-Report for DAPS handover and if the last executedRRCReconfigurationmessage includingreconfigurationWithSyncwas concerning a DAPS handover:

[0533] 5> setlastHO-Typetodaps;

[0534] 4> else if the UE supports RLF-Report for conditional handover and if the last executedRRCReconfigurationmessage includingreconfigurationWithSyncwas concerning a conditional handover:

[0535] 5> setlastHO-Typetocho;

[0536] 4> else if the UE supports RLF-Report for MCG LTM cell switch and the last executedRRCReconfigurationmessage includingreconfigurationWithSyncwas concerning an LTM cell switch:

[0537] 5> setlastHO-Typetoltm;

[0538] 4> if the UE supports RLF-Report for conditional handover with candidate SCG and if the last executedRRCReconfigurationmessage includingreconfigurationWithSyncwas concerning conditional handover with candidate SCG:

[0539] 5> setlastHO-TypetochoWithCandidateSCG;

[0540] 4> set thetimeConnFailureto the elapsed time since the execution of the lastRRCReconfigurationmessage including thereconfigurationWithSync;

[0541] 3> else if the lastRRCReconfigurationmessage including thereconfigurationWithSyncconcerned a handover to NR from E-UTRA and if the UE supports Radio Link Failure Report for Inter-RAT MRO EUTRA:

[0542] 4> include theeutraPreviousCellinpreviousPCellIdand set it to the global cell identity and the tracking area code of the E-UTRA PCell where the lastRRCReconfigurationmessage includingreconfigurationWithSyncwas received embedded in E-UTRA RRC messageMobilityFromEUTRACommandmessage;

[0543] 4> set thetimeConnFailureto the elapsed time since reception of the lastRRCReconfigurationmessage including thereconfigurationWithSyncembedded in E-UTRA RRC messageMobilityFromEUTRACommandmessage;

[0544] 2> if configuration of the conditional handover is available in the MCGVarConditionalReconfigat the moment of declaring the radio link failure:

[0545] 3> settimeSinceCHO-Reconfigto the time elapsed between the detection of the radio link failure, and the reception, in the source PCell, of the lastconditionalReconfigurationincluding thecondRRCReconfigmessage;

[0546] 3> setchoCandidateCellListto include the global cell identity if available, and otherwise to the physical cell identity and carrier frequency of each of all the candidate target cells for conditional handover included incondRRCReconfigwithin the MCGVarConditionalReconfigat the time of radio link failure, excluding the candidate target cells included inmeasResultNeighCells;

[0547] 1> ifconnectionFailureTypeisrlfand therlf-Causeis set torandomAccessProblemorbeamFailureRecoveryFailure; or

[0548] 1> ifconnectionFailureTypeisrlfand therlf-Causeis set tolbtFailureand the radio link failure is detected during the random access procedure; or

[0549] 1> ifconnectionFailureTypeishofand if the failed handover is an intra-RAT reconfiguration with sync and if a random-access procedure was triggered for the failed reconfiguration with sync:

[0550] 2> set thera-InformationCommonto include the random-access related information;

[0551] 1> ifconnectionFailureTypeisrlfand therlf-Causeis set tolbtFailure, and the radio link failure is not detected during the random access procedure:

[0552] 2> set thelocationAndBandwidthandsubcarrierSpacinginbwp-Infoassociated to the UL BWP in which the consistent uplink LBT failure was detected;

[0553] 1> if therlf-Causeis set tot310-Expiryort312-Expiry:

[0554] 2> set thessbRLMConfigBitmapand / orcsi-rsRLMConfigBitmapinmeasResultLastServCellto include the radio link monitoring configuration of the last serving cell, if available;

[0555] 1> if available, set thelocationInfo.

[0556] The UE may discard the radio link failure information or handover failure information, i.e. release the UE variableVarRLF-Report, 48 hours after the radio link failure / handover failure is detected.

[0557] In the present disclosure, the term 'handover failure' has been used to refer to 'mobility failure' and / or 'reconfiguration with sync failure'.

[0558] The UE shall set the contents of theSCGFailureInformationmessage as follows:

[0559] 1> if the UE initiates transmission of theSCGFailureInformationmessage due to T310 expiry:

[0560] 2> set thefailureTypeast310-Expiry;

[0561] 1> else if the UE initiates transmission of theSCGFailureInformationmessage due to T312 expiry:

[0562] 2> set thefailureTypeasotherand set thefailureType-v1610ast312-Expiry;

[0563] 1> else if the UE initiates transmission of theSCGFailureInformationmessage to provide reconfiguration with sync failure information for an SCG:

[0564] 2> set thefailureTypeassynchReconfigFailureSCG;

[0565] 1> else if the UE initiates transmission of theSCGFailureInformationmessage to provide random access problem indication from SCG MAC:

[0566] 2> if the random access procedure was initiated for beam failure recovery:

[0567] 3> set thefailureTypeasotherand set thefailureType-v1610asbeamFailureRecoveryFailure;

[0568] 2> else:

[0569] 3> set thefailureType asrandomAccessProblem;

[0570] 1> else if the UE initiates transmission of theSCGFailureInformationmessage to provide indication from SCG RLC that the maximum number of retransmissions has been reached:

[0571] 2> set thefailureTypeasrlc-MaxNumRetx;

[0572] 1> else if the UE initiates transmission of theSCGFailureInformationmessage due to SRB3 IP check failure:

[0573] 2> set thefailureTypeassrb3-IntegrityFailure;

[0574] 1> else if the UE initiates transmission of theSCGFailureInformationmessage due to Reconfiguration failure of NR RRC reconfiguration message:

[0575] 2> set thefailureTypeasscg-reconfigFailure;

[0576] 1> else if the UE initiates transmission of theSCGFailureInformationmessage due to consistent uplink LBT failures:

[0577] 2> set thefailureTypeasotherand set thefailureType-v1610asscg-lbtFailure;

[0578] 1> else if connected as an IAB-node and theSCGFailureInformationis initiated due to the reception of a BH RLF indication on BAP entity from the SCG:

[0579] 2> set thefailureTypeasotherand setfailureType-v1610asbh-RLF;

[0580] 1> else if the UE initiates transmission of theSCGFailureInformationmessage due to beam failure of the PSCell while the SCG is deactivated:

[0581] 2> set thefailureTypeasotherand setfailureType-v1610asbeamFailure;

[0582] 1> include and setMeasResultSCG-Failure;

[0583] 1> for eachMeasObjectNRconfigured by aMeasConfigassociated with the MCG, and for which measurement results are available:

[0584] 2> include an entry inmeasResultFreqList;

[0585] 2> if there is ameasIdconfigured with theMeasObjectNRand areportConfigwhich hasrsTypeset tossb:

[0586] 3> setssbFrequencyinmeasResultFreqListto the value indicated byssbFrequencyas included in theMeasObjectNR;

[0587] 2> if there is ameasIdconfigured with theMeasObjectNRand areportConfigwhich hasrsTypeset tocsi-rs:

[0588] 3> setrefFreqCSI-RSinmeasResultFreqListto the value indicated byrefFreqCSI-RSas included in the associated measurement object;

[0589] 2> if a serving cell is associated with theMeasObjectNR:

[0590] 3> setmeasResultServingCellinmeasResultFreqListto include the available quantities of the concerned cell and in accordance with the performance requirements;

[0591] 2> set themeasResultNeighCellListinmeasResultFreqListto include the best measured cells, ordered such that the best cell is listed first, and based on measurements collected up to the moment the UE detected the failure, and set its fields as follows;

[0592] 3> ordering the cells with sorting as follows:

[0593] 4> based on SS / PBCH block if SS / PBCH block measurement results are available and otherwise based on CSI-RS;

[0594] 4> using RSRP if RSRP measurement results are available, otherwise using RSRQ if RSRQ measurement results are available, otherwise using SINR;

[0595] 3> if the UE supports SCG failure information for mobility robustness optimization for conditional PSCell change or addition or if the UE supports SCG failure information for mobility robustness optimization for CHO with candidate SCG, for each neighbour cell, if any, included inmeasResultListNRinmeasResultFreqList:

[0596] 4> if the neighbour cell is one of the candidate cells for which thereconfigurationWithSyncis included in thesecondaryCellGroupin the MCGVarConditionalReconfig(for CPA or inter-SN CPC in NR-DC) or SCGVarConditionalReconfig(for intra-SN CPC) at the moment of the detected SCG failure (radio link failure at PSCell or PSCell change or addition failure):

[0597] 5> if the first entry ofcondExecutionCondorcondExecutionCondSCGassociated to the neighbour cell corresponds to a fulfilled execution condition at the moment of SCG failure; or

[0598] 5> if the second entry ofcondExecutionCondorcondExecutionCondSCGassociated to the neighbour cell, if available, corresponds to a fulfilled execution condition at the moment of SCG failure:

[0599] 6> setfirstTriggeredEventto the execution conditioncondFirstEventcorresponding to the first entry ofcondExecutionCondorcondExecutionCondSCGassociated to the neighbour cell or to the execution conditioncondSecondEventcorresponding to the second entry ofcondExecutionCondorcondExecutionCondSCGassociated to the neighbour cell, whichever execution condition was fulfilled first in time;

[0600] 6> settimeBetweenEventsto the elapsed time between the point in time of fulfilling the condition incondExecutionCondorcondExecutionCondSCGassociated to the neighbour cell that was fulfilled first in time, and the point in time of fulfilling the condition incondExecutionCondorcondExecutionCondSCGassociated to the neighbour cell that was fulfilled second in time, if both the first execution condition corresponding to the first entry and the second execution condition corresponding to the second entry in thecondExecutionCondorcondExecutionCondSCGassociated to the neighbour cellwere fulfilled;

[0601] 3> if the UE supports SCG failure information for mobility robustness optimization for conditional handover with candidate SCG, for each neighbour cell, if any, included inmeasResultListNRinmeasResultFreqList:

[0602] 4> if the neighbour cell is one of the candidate cells for which thereconfigurationWithSyncis associated with bothcondExecutionCondandcondExecutionCondPSCellin the MCGVarConditionalReconfigat the moment of the detected SCG failure (radio link failure at PSCell or PSCell change or addition failure):

[0603] 5> if the first entry ofcondExecutionCondassociated to the neighbour cell corresponds to a fulfilled execution condition at the moment of SCG failure; or

[0604] 5> if the second entry ofcondExecutionCondassociated to the neighbour cell, if available, corresponds to a fulfilled execution condition at the moment of SCG failure:

[0605] 6> setfirstTriggeredEventto the execution conditioncondFirstEventcorresponding to the first entry ofcondExecutionCondassociated to the neighbour cell or to the execution conditioncondSecondEventcorresponding to the second entry ofcondExecutionCondassociated to the neighbour cell, whichever execution condition was fulfilled first in time;

[0606] 6> settimeBetweenEventsto the elapsed time between the point in time of fulfilling the condition incondExecutionCondassociated to the neighbour cell that was fulfilled first in time, and the point in time of fulfilling the condition incondExecutionCondassociated to the neighbour cell that was fulfilled second in time, if both the first execution condition corresponding to the first entry and the second execution condition corresponding to the second entry in thecondExecutionCondassociated to the neighbour cellwere fulfilled;

[0607] 3> for each neighbour cell included:

[0608] 4> include the optional fields that are available.

[0609] The measured quantities are filtered by the L3 filter as configured in the mobility measurement configuration. The measurements are based on the time domain measurement resource restriction, if configured. Exclude-listed cells are not required to be reported.

[0610] FieldmeasResultSCG-Failureis used to report available results for NR frequencies the UE is configured to measure by SCG RRC signalling.

[0611] 1> for each entry ofcondReconfigListin the MCGVarConditionalReconfigincluding bothcondExecutionCondandcondExecutionCondPSCell, include an entry incho-WithCandidateSCGInfoListand set the values as follows:

[0612] 2> if all triggering eventsof bothcondExecutionCondandcondExecutionCondPSCellof the concerned entry ofcondReconfigListare fulfilled:

[0613] 3> setfirstFulfilledConfigtochoifcondExecutionCondwas fulfilled first orcpcifcondExecutionCondPSCellwas fulfilled first;

[0614] 3> settimeBetweenFulfillmentto the elapsed time between the fulfillments of the last triggering events of the two execution conditions;

[0615] 2> else if all triggering eventsof only one of thecondExecutionCondorcondExecutionCondPSCellof the concerned entry ofcondReconfigListis fulfilled:

[0616] 3> setfirstFulfilledConfigtochoorcpc, whichever was fulfilled;

[0617] 3> settimeBetweenLastFulfillmentAndEventto the elapsed time between the point in time of fulfilling the last triggering event of the fulfilled execution condition and the SCG failure;

[0618] 2> else if all triggering events of any ofcondExecutionCondandcondExecutionCondPSCellare fulfilled:

[0619] 3> set thepCellIdto the global cell identity and tracking area code, if available, and otherwise the physical cell identity and carrier frequency, of the target candidate PCell stored in thecondRRCReconfigof the concerned entry ofcondReconfigList;

[0620] 3> set thepsCellIdto the global cell identity and tracking area code, if available, and otherwise the physical cell identity and carrier frequency, of the target candidate PSCell stored in thecondRRCReconfigof the concerned entry ofcondReconfigList;

[0621] 1> if available, set thelocationInfoaccording to theotherConfigassociated with the NR MCG.

[0622] 1> if the UE supports SCG failure for mobility robustness optimization:

[0623] 2> if thefailureTypeis set tosynchReconfigFailureSCG; or

[0624] 2> if thefailureTypeis set torandomAccessProblemand the SCG failure was declared while T304 was running:

[0625] 3> setperRAInfoListto indicate the performed random access procedure related information.

[0626] 3> set thefailedPSCellIdto the physical cell identity and carrier frequency of the target PSCell of the failed PSCell change or failed PSCell addition;

[0627] 3> if the failure occurred during a subsequent CPC:

[0628] 4> set thepreviousPSCellIdto the physical cell identity and carrier frequency of the source PSCell associated to the last execution ofRRCReconfigurationmessage includingreconfigurationWithSyncfor the SCG, if available;

[0629] 3> else:

[0630] 4> set thepreviousPSCellIdto the physical cell identity and carrier frequency of the source PSCell associated to the last receivedRRCReconfigurationmessage includingreconfigurationWithSyncfor the SCG, if available;

[0631] 3> set thetimeSCGFailureto the elapsed time since the last execution ofRRCReconfigurationmessage including thereconfigurationWithSyncfor the SCG until declaring the SCG failure;

[0632] 2> else:

[0633] 3> set thefailedPSCellIdto the physical cell identity and carrier frequency of the PSCell in which the SCG failure was declared;

[0634] 3> if the lastRRCReconfigurationmessage including thereconfigurationWithSyncfor the SCG was received to enter the PSCell in which the SCG failure was declared:

[0635] 4> set thetimeSCGFailureto the elapsed time since the last execution ofRRCReconfigurationmessage including thereconfigurationWithSyncfor the SCG until declaring the SCG failure;

[0636] 4> if the failure occurred after a subsequent CPC:

[0637] 5> set thepreviousPSCellIdto the physical cell identity and carrier frequency of the source PSCell associated to the last execution ofRRCReconfigurationmessage includingreconfigurationWithSyncfor the SCG, if available;

[0638] 4> else:

[0639] 5> set thepreviousPSCellIdto the physical cell identity and carrier frequency of the source PSCell associated to the last receivedRRCReconfigurationmessage includingreconfigurationWithSyncfor the SCG;

[0640] 1> releasesuccessPSCell-Configconfigured by the source PSCell, if available.

[0641] The UE shall submit theSCGFailureInformationmessage to lower layers for transmission.

[0642] According to various embodiments, UE may declare an SCG Radio Link Failure (RLF) due to a radio problem in the PSCell. The UE may construct SCG failure information. The SCG failure information may include only CPAC-related logging information from CHO and associated CPAC execution condition evaluation results. The CPAC-related logging information may comprise information for a time gap between the first satisfied condition and the SCG RLF occurrence. The UE may include an identifier in the SCG failure information to indicate that the CHO and the associated CPAC evaluation results originated from the same timing. The UE may send the SCG failure information to the network for SCG recovery. The UE may declare an MCG RLF due to a radio problem in the PCell. The UE may construct an MCG RLF-report comprising only CHO-related logging information from CHO and the associated CPAC execution condition evaluation results. The CHO-related logging information may comprise information for a time gap between the first satisfied condition and the MCG RLF occurrence. The UE may include the identifier in the RLF-report to indicate that the CHO and the associated CPAC evaluation results originated from the same timing.

[0643] According to various embodiments, UE may declare an SCG Radio Link Failure (RLF) due to a radio problem in the PSCell. The UE may construct SCG failure information. The SCG failure information may include CHO and the associated CPAC information from CHO and the associated CPAC execution condition evaluation results. The SCG failure information may comprise information for a time gap between the first satisfied condition and the SCG RLF occurrence. The UE may send the SCG failure information to the network for SCG recovery. The UE may declare an MCG RLF due to a radio problem in the PCell. The UE may check if the CHO and / or the associated CPAC information are logged before. The UE may construct an MCG RLF-report, where the RLF-report excludes the CHO and / or the associated CPAC information.

[0644] According to various embodiments, UE may declare an SCG Radio Link Failure (RLF) due to a radio problem in the PSCell. The UE may construct SCG failure information. The SCG failure information may include CHO and the associated CPAC information from CHO and the associated CPAC execution condition evaluation results. The SCG failure information may comprise information for a time gap between the first satisfied condition and the SCG RLF occurrence. The UE may send the SCG failure information to the network for SCG recovery. The UE may remove the CHO and the associated CPAC execution condition evaluation results before / after sending the SCG failure information. The UE may declare an MCG RLF due to a radio problem in the PCell. The UE may check if the CHO and / or the associated CPAC information are logged before. The UE may construct an MCG RLF-report, where the RLF-report excludes the CHO and / or the associated CPAC information.

[0645] Furthermore, the method in perspective of the communication device / UE described in the present disclosure (e.g., in FIG. 11) may be performed by the first wireless device 100 shown in FIG. 2 and / or the UE 100 shown in FIG. 3.

[0646] More specifically, the communication device / UE comprises at least one transceiver, at least processor, and at least one computer memory operably connectable to the at least one processor and storing instructions that, based on being executed by the at least one processor, perform operations.

[0647] The operations comprise: receiving a conditional reconfiguration comprising execution conditions including: one or more execution conditions for conditional handover (CHO) for a candidate primary cell (PCell); and one or more execution conditions for primary secondary cell (PSCell) mobility for a candidate PSCell related to the candidate PCell; evaluating the one or more execution conditions for CHO and the one or more execution conditions for PSCell mobility; based on detecting a failure related to a master cell group (MCG), transmitting a radio link failure (RLF) report comprising one or more first evaluation results among evaluation results of the execution conditions; and based on detecting a failure related to a secondary cell group (SCG), transmitting SCG failure information comprising one or more second evaluation results among the evaluation results of the execution conditions.

[0648] Furthermore, the method in perspective of the communication device / UE described in the present disclosure (e.g., in FIG. 11) may be performed by a software code 105 stored in the memory 104 included in the first wireless device 100 shown in FIG. 2.

[0649] More specifically, at least one computer readable medium (CRM) stores instructions that, based on being executed by at least one processor, perform operations comprising: receiving a conditional reconfiguration comprising execution conditions including: one or more execution conditions for conditional handover (CHO) for a candidate primary cell (PCell); and one or more execution conditions for primary secondary cell (PSCell) mobility for a candidate PSCell related to the candidate PCell; evaluating the one or more execution conditions for CHO and the one or more execution conditions for PSCell mobility; based on detecting a failure related to a master cell group (MCG), transmitting a radio link failure (RLF) report comprising one or more first evaluation results among evaluation results of the execution conditions; and based on detecting a failure related to a secondary cell group (SCG), transmitting SCG failure information comprising one or more second evaluation results among the evaluation results of the execution conditions.

[0650] Furthermore, the method in perspective of the communication device / UE described in the present disclosure (e.g., in FIG. 11) may be performed by control of the processor 102 included in the first wireless device 100 shown in FIG. 2 and / or by control of the processor 102 included in the UE 100 shown in FIG. 3.

[0651] More specifically, an apparatus configured to / adapted to operate in a wireless communication system (e.g., communication device / UE) comprises at least processor, and at least one computer memory operably connectable to the at least one processor. The at least one processor is configured to / adapted to perform operations comprising: receiving a conditional reconfiguration comprising execution conditions including: one or more execution conditions for conditional handover (CHO) for a candidate primary cell (PCell); and one or more execution conditions for primary secondary cell (PSCell) mobility for a candidate PSCell related to the candidate PCell; evaluating the one or more execution conditions for CHO and the one or more execution conditions for PSCell mobility; based on detecting a failure related to a master cell group (MCG), transmitting a radio link failure (RLF) report comprising one or more first evaluation results among evaluation results of the execution conditions; and based on detecting a failure related to a secondary cell group (SCG), transmitting SCG failure information comprising one or more second evaluation results among the evaluation results of the execution conditions.

[0652] Furthermore, the method in perspective of a network node described in the present disclosure (e.g., in FIG. 12) may be performed by the second wireless device 200 shown in FIG. 2. The network node may be related to a serving cell.

[0653] More specifically, the network node comprises at least one transceiver, at least processor, and at least one computer memory operably connectable to the at least one processor and storing instructions that, based on being executed by the at least one processor, perform operations.

[0654] The operations comprise: transmitting, to a user equipment (UE), a conditional reconfiguration comprising execution conditions including: one or more execution conditions for conditional handover (CHO) for a candidate primary cell (PCell); and one or more execution conditions for primary secondary cell (PSCell) mobility for a candidate PSCell related to the candidate PCell; receiving, from the UE, a radio link failure (RLF) report comprising one or more first evaluation results among evaluation results of the execution conditions, based on an occurrence of a failure related to a master cell group (MCG); and receiving, from the UE, SCG failure information comprising one or more second evaluation results among the evaluation results of the execution conditions, based on an occurrence of a failure related to a secondary cell group (SCG).

[0655] The present disclosure may have various advantageous effects.

[0656] For example, the UE can prevent redundant reporting of the same evaluation results across different reports. Thus, the network can correctly sample and adjust the CHO and the associated CPAC configuration without misinterpretation. Therefore, it can　reduce the risk of　incorrect handover timing,　prevent　unnecessary RLFs, and　optimize　power consumption.

[0657] Advantageous effects which can be obtained through specific embodiments of the present disclosure are not limited to the advantageous effects listed above. For example, there may be a variety of technical effects that a person having ordinary skill in the related art can understand and / or derive from the present disclosure. Accordingly, the specific effects of the present disclosure are not limited to those explicitly described herein, but may include various effects that may be understood or derived from the technical features of the present disclosure.

[0658] Claims in the present disclosure can be combined in a various way. For instance, technical features in method claims of the present disclosure can be combined to be implemented or performed in an apparatus, and technical features in apparatus claims can be combined to be implemented or performed in a method. Further, technical features in method claim(s) and apparatus claim(s) can be combined to be implemented or performed in an apparatus. Further, technical features in method claim(s) and apparatus claim(s) can be combined to be implemented or performed in a method. Other implementations are within the scope of the following claims.

Claims

1.A method comprising:receiving a conditional reconfiguration comprising execution conditions including:one or more execution conditions for conditional handover (CHO) for a candidate primary cell (PCell); andone or more execution conditions for primary secondary cell (PSCell) mobility for a candidate PSCell related to the candidate PCell;evaluating the one or more execution conditions for CHO and the one or more execution conditions for PSCell mobility;based on detecting a failure related to a master cell group (MCG), transmitting a radio link failure (RLF) report comprising one or more first evaluation results among evaluation results of the execution conditions; andbased on detecting a failure related to a secondary cell group (SCG), transmitting SCG failure information comprising one or more second evaluation results among the evaluation results of the execution conditions.2.The method of claim 1, wherein the failure related to the MCG comprises at least one of a radio link failure (RLF) on the MCG, or a failure of the CHO; andwherein the failure related to the SCG comprises at least one of an RLF on the SCG or a failure of the PSCell mobility.3.The method of claim 1, wherein the conditional reconfiguration comprises a configuration of the candidate PCell,wherein the configuration of the candidate PCell comprises an SCG configuration, andwherein the SCG configuration comprises a configuration of the candidate PSCell related to the candidate PCell.4.The method of claim 1, further comprising performing a mobility based on both of i) the one or more execution conditions for CHO and ii) the one or more execution conditions for PSCell mobility being fulfilled,wherein the mobility comprises at least one of CHO to the candidate PCell, or PSCell mobility to the candidate PSCell.5.The method of claim 1, wherein the one or more first evaluation results comprise at least one of:at least part of evaluation results of the one or more execution conditions for CHO; orat least part of evaluation results of the one or more execution conditions for PSCell mobility; andwherein the one or more second evaluation results comprise at least one of:remaining part of the evaluation results of the one or more execution conditions for CHO; orremaining part of the evaluation results of the one or more execution conditions for PSCell mobility.6.The method of claim 5, wherein the evaluation results of the one or more execution conditions for CHO comprise at least one of:information for whether the one or more execution conditions for CHO are fulfilled;information for whether the one or more execution conditions for CHO are fulfilled first among the execution conditions;information for an elapsed time between fulfillments of the one or more execution conditions for CHO and the one or more execution conditions for PSCell mobility;information for an elapsed time between a point in time of fulfilling the one or more execution conditions for CHO and the failure related to the MCG;information for an execution condition that is fulfilled first among the one or more execution conditions for CHO; orinformation for an elapsed time between points in time of fulfilling the one or more execution conditions for CHO.7.The method of claim 5, wherein the evaluation results of the one or more execution conditions for PSCell mobility comprise at least one of:information for whether the one or more execution conditions for PSCell mobility are fulfilled;information for whether the one or more execution conditions for PSCell mobility are fulfilled first among the execution conditions;information for an elapsed time between fulfillments of the one or more execution conditions for CHO and the one or more execution conditions for PSCell mobility;information for an elapsed time between a point in time of fulfilling the one or more execution conditions for PSCell mobility and the failure related to the SCG;information for an execution condition that is fulfilled first among the one or more execution conditions for PSCell mobility; orinformation for an elapsed time between points in time of fulfilling the one or more execution conditions for PSCell mobility.8.The method of claim 1, wherein the RLF report excludes the one or more second evaluation results, andwherein the SCG failure information excludes the one or more first evaluation results.9.The method of claim 1, further comprising:discarding the one or more first evaluation results based on logging the one or more first evaluation results in the RLF report; anddiscarding the one or more second evaluation results based on logging the one or more second evaluation results in the SCG failure information.10.The method of claim 1, wherein the one or more first evaluation results comprise the evaluation results of the one or more execution conditions for CHO, andwherein the one or more second evaluation results comprise the evaluation results of the one or more execution conditions for PSCell mobility.11.The method of claim 1, wherein each of the RLF report and the SCG failure information comprises:both of the evaluation results of the one or more execution conditions for CHO and the evaluation results of the one or more execution conditions for PSCell mobility; andinformation informing that both of the RLF report and the SCG failure information comprise same evaluation results.12.The method of claim 11, wherein the information comprises at least one of an identifier of the PCell or an identifier of the PSCell.13.The method of claim 1, wherein the PSCell mobility comprises at least one of a PSCell change to the candidate PSCell, or PSCell addition of the candidate PSCell.14.The method of claims 1 to 13, wherein the method is performed by a user equipment (UE) in communication with at least one of a mobile device, a network, or autonomous vehicles.15.A user equipment (UE) comprising:at least one transceiver;at least one processor; andat least one memory operatively coupled to the at least one processor and storing instructions that, based on being executed by the at least one processor, perform operations comprising:receiving a conditional reconfiguration comprising execution conditions including:one or more execution conditions for conditional handover (CHO) for a candidate primary cell (PCell); andone or more execution conditions for primary secondary cell (PSCell) mobility for a candidate PSCell related to the candidate PCell;evaluating the one or more execution conditions for CHO and the one or more execution conditions for PSCell mobility;based on detecting a failure related to a master cell group (MCG), transmitting a radio link failure (RLF) report comprising one or more first evaluation results among evaluation results of the execution conditions; andbased on detecting a failure related to a secondary cell group (SCG), transmitting SCG failure information comprising one or more second evaluation results among the evaluation results of the execution conditions.16.An apparatus comprising:at least processor; andat least one memory operatively coupled to the at least one processor and storing instructions that, based on being executed by the at least one processor, perform operations comprising:receiving a conditional reconfiguration comprising execution conditions including:one or more execution conditions for conditional handover (CHO) for a candidate primary cell (PCell); andone or more execution conditions for primary secondary cell (PSCell) mobility for a candidate PSCell related to the candidate PCell;evaluating the one or more execution conditions for CHO and the one or more execution conditions for PSCell mobility;based on detecting a failure related to a master cell group (MCG), transmitting a radio link failure (RLF) report comprising one or more first evaluation results among evaluation results of the execution conditions; andbased on detecting a failure related to a secondary cell group (SCG), transmitting SCG failure information comprising one or more second evaluation results among the evaluation results of the execution conditions.17.A non-transitory computer readable medium (CRM) having stored thereon a program code implementing instructions that, based on being executed by at least one processor, perform operations comprising:receiving a conditional reconfiguration comprising execution conditions including:one or more execution conditions for conditional handover (CHO) for a candidate primary cell (PCell); andone or more execution conditions for primary secondary cell (PSCell) mobility for a candidate PSCell related to the candidate PCell;evaluating the one or more execution conditions for CHO and the one or more execution conditions for PSCell mobility;based on detecting a failure related to a master cell group (MCG), transmitting a radio link failure (RLF) report comprising one or more first evaluation results among evaluation results of the execution conditions; andbased on detecting a failure related to a secondary cell group (SCG), transmitting SCG failure information comprising one or more second evaluation results among the evaluation results of the execution conditions.18.A method comprising:transmitting, to a user equipment (UE), a conditional reconfiguration comprising execution conditions including:one or more execution conditions for conditional handover (CHO) for a candidate primary cell (PCell); andone or more execution conditions for primary secondary cell (PSCell) mobility for a candidate PSCell related to the candidate PCell;receiving, from the UE, a radio link failure (RLF) report comprising one or more first evaluation results among evaluation results of the execution conditions, based on an occurrence of a failure related to a master cell group (MCG); andreceiving, from the UE, SCG failure information comprising one or more second evaluation results among the evaluation results of the execution conditions, based on an occurrence of a failure related to a secondary cell group (SCG).19.A network node comprising:at least one transceiver;at least one processor; andat least one memory operatively coupled to the at least one processor and storing instructions that, based on being executed by the at least one processor, perform operations comprising:transmitting, to a user equipment (UE), a conditional reconfiguration comprising execution conditions including:one or more execution conditions for conditional handover (CHO) for a candidate primary cell (PCell); andone or more execution conditions for primary secondary cell (PSCell) mobility for a candidate PSCell related to the candidate PCell;receiving, from the UE, a radio link failure (RLF) report comprising one or more first evaluation results among evaluation results of the execution conditions, based on an occurrence of a failure related to a master cell group (MCG); andreceiving, from the UE, SCG failure information comprising one or more second evaluation results among the evaluation results of the execution conditions, based on an occurrence of a failure related to a secondary cell group (SCG).

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