Logging synchronization information

Abstract

A method and apparatus for logging Downlink (DL) / Uplink (UL) (re-)synchronization information is provided. A wireless device receives time information and a logging condition from the network. The wireless device performs DL / UL synchronization based on the time information. The wireless device logs results of the DL / UL synchronization based on the logging condition being met, and reports the results of the DL / UL synchronization to the network.

Description

LOGGING SYNCHRONIZATION INFORMATION

[0001] The present disclosure relates to logging Downlink (DL) / Uplink (UL) (re-)synchronization information.

[0002] 3rd Generation Partnership Project (3GPP) New Radio (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. 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.

[0003] 6G is the successor to 5G cellular technology. 6G networks will be able to use higher frequencies than 5G networks and provide substantially higher capacity and much lower latency. The 6G technology market is expected to facilitate large improvements in the areas of imaging, presence technology and location awareness. Working in conjunction with Artificial Intelligence (AI), the 6G computational infrastructure will be able to identify the best place for computing to occur. This includes decisions about data storage, processing and sharing.

[0004] Non-Terrestrial Network (NTN) is being studied. The basic idea of NTN is to deliver 5G / NR service via space (satellite) or air (airborne platform). If it is realized as expected, it would be able to deliver the 5G service to those places where it is technically very difficult or cost too much to deliver with terrestrial network. Some examples of those places would be a remote area like deep forest that would be too costly with terrestrial delivery, or far islands or ship that would be technically almost forbidden in terrestrial connection.

[0005] In an aspect, a method is provided. The method comprises receiving time information from a network, receiving a logging condition from the network, performing downlink (DL) / uplink (UL) synchronization based on the time information, logging results of the DL / UL synchronization based on the logging condition being met, and reporting the results of the DL / UL synchronization to the network.

[0006] In another aspect, an apparatus for implementing the above method is provided.

[0007] FIG. 1 shows an example of a communication system to which implementations of the present disclosure are applied.

[0008] FIG. 2 shows an example of wireless devices to which implementations of the present disclosure are applied.

[0009] FIG. 3 shows an example of UE to which implementations of the present disclosure are applied.

[0010] FIGS. 4 and 5 show an example of protocol stacks in a 3GPP based wireless communication system to which implementations of the present disclosure are applied.

[0011] FIG. 6 shows a frame structure in a 3GPP based wireless communication system to which implementations of the present disclosure are applied.

[0012] FIG. 7 shows a data flow example in the 3GPP NR system to which implementations of the present disclosure are applied.

[0013] FIG. 8 shows an example of a Non-Terrestrial Network (NTN) to which implementations of the present disclosure are applied.

[0014] FIG. 9 shows an example of illustration of timing relationship for collocated gNB and NTN Gateway to which implementations of the present disclosure are applied.

[0015] FIG. 10 shows an example of a method to which implementations of the present disclosure are applied.

[0016] FIG. 11 shows an example of another method to which implementations of the present disclosure are applied.

[0017] 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, 5G New Radio (NR) and / or 6G.

[0018] 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.

[0019] 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.

[0020] 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".

[0021] 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".

[0022] 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".

[0023] 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".

[0024] 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".

[0025] Technical features that are separately described in one drawing in the present disclosure may be implemented separately or simultaneously.

[0026] 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.

[0027] 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.

[0028] FIG. 1 shows an example of a communication system to which implementations of the present disclosure are applied.

[0029] 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.

[0030] 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).

[0031] 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.

[0032] 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.

[0033] 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.

[0034] 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.

[0035] 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.

[0036] 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.

[0037] 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.

[0038] 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).

[0039] Frequency Range designationCorresponding frequency rangeSubcarrier SpacingFR1450MHz - 6000MHz15, 30, 60kHzFR224250MHz - 52600MHz60, 120, 240kHz

[0040] 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).

[0041] Frequency Range designationCorresponding frequency rangeSubcarrier SpacingFR1410MHz - 7125MHz15, 30, 60kHzFR224250MHz - 52600MHz60, 120, 240kHz

[0042] 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.

[0043] FIG. 2 shows an example of wireless devices to which implementations of the present disclosure are applied.

[0044] 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.

[0045] 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.

[0046] 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.

[0047] 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.

[0048] 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.

[0049] 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.

[0050] 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.

[0051] 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.

[0052] 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.

[0053] 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.

[0054] 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.

[0055] 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.

[0056] 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.

[0057] 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.

[0058] 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.

[0059] 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).

[0060] 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.

[0061] 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.

[0062] In the implementations of the present disclosure, a UE may operate as a transmitting device in UL and as a receiving device in 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.

[0063] In the present disclosure, a BS is also referred to as a node B (NB), an eNode B (eNB), or a gNB.

[0064] FIG. 3 shows an example of UE to which implementations of the present disclosure are applied.

[0065] Referring to FIG. 3, a UE 100 may correspond to the first wireless device 100 of FIG. 2.

[0066] 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.

[0067] 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.

[0068] 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.

[0069] 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.

[0070] 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.

[0071] 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.

[0072] 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.

[0073] 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.

[0074] FIGS. 4 and 5 show an example of protocol stacks in a 3GPP based wireless communication system to which implementations of the present disclosure are applied.

[0075] 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 (i.e., a PHY layer) and Layer 2. Referring to FIG. 5, the control plane protocol stack may be divided into Layer 1 (i.e., a PHY layer), Layer 2, Layer 3 (e.g., 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).

[0076] 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.

[0077] 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.

[0078] 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.

[0079] The RLC sublayer supports three transmission modes: Transparent Mode (TM), Unacknowledged Mode (UM), and Acknowledged Mode (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).

[0080] 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.

[0081] 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.

[0082] 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 5G Core network (5GC) or Next-Generation Radio Access Network (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 Signaling Radio Bearers (SRBs) and Data Radio Bearers (DRBs); mobility functions (including: handover and context transfer, UE cell selection and reselection and control of cell selection and reselection, inter-RAT mobility); QoS management functions; 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.

[0083] FIG. 6 shows a frame structure in a 3GPP based wireless communication system to which implementations of the present disclosure are applied.

[0084] 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., 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 Cyclic Prefix (CP)-OFDM symbols), SC-FDMA symbols (or Discrete Fourier Transform-spread-OFDM (DFT-s-OFDM) symbols).

[0085] 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 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 Δf = 2u*15 kHz.

[0086] 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 Δf = 2u*15 kHz.

[0087] uNslotsymbNframe,uslotNsubframe,uslot01410111420221440431480841416016

[0088] 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 Δf = 2u*15 kHz.

[0089] uNslotsymbNframe,uslotNsubframe,uslot212404

[0090] 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 signaling (e.g., RRC signaling), 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.

[0091] 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.

[0092] 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.

[0093] 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 Physical Uplink Control Channel (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.

[0094] FIG. 7 shows a data flow example in the 3GPP NR system to which implementations of the present disclosure are applied.

[0095] 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.

[0096] 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 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.

[0097] FIG. 8 shows an example of a Non-Terrestrial Network (NTN) to which implementations of the present disclosure are applied.

[0098] The NTN provides non-terrestrial NR access to the UE by means of an NTN payload and an NTN Gateway. Referring to FIG. 8, a service link between the NTN payload and a UE, and a feeder link between the NTN Gateway and the NTN payload are described.

[0099] The NTN payload transparently forwards the radio protocol received from the UE (via the service link) to the NTN Gateway (via the feeder link) and vice-versa. The following connectivity is supported by the NTN payload:

[0100] - A NTN gateway may serve multiple NTN payloads;

[0101] - An NTN payload may be served by multiple NTN gateways.

[0102] The NTN payload may change the carrier frequency, before re-transmitting it on the service link, and vice versa (respectively on the feeder link).

[0103] For NTN, the following network identities (IDs) are further applied.

[0104] - A Tracking Area (TA) corresponds to a fixed geographical area. Any respective mapping is configured in the RAN;

[0105] - A Mapped Cell ID

[0106] Three types of service links are supported:

[0107] - Earth-fixed: provisioned by beam(s) continuously covering the same geographical areas all the time (e.g., the case of Geosynchronous Orbit (GSO) satellites);

[0108] - Quasi-Earth-fixed: provisioned by beam(s) covering one geographic area for a limited period and a different geographic area during another period (e.g., the case of Non-Geosynchronous Orbit (NGSO) satellites generating steerable beams);

[0109] - Earth-moving: provisioned by beam(s) whose coverage area slides over the Earth surface (e.g., the case of NGSO satellites generating fixed or non-steerable beams).

[0110] With NGSO satellites, the gNB may provide either quasi-Earth-fixed service link or Earth-moving service link, while gNB operating with GSO satellite may provide Earth-fixed service link.

[0111] FIG. 9 shows an example of illustration of timing relationship for collocated gNB and NTN Gateway to which implementations of the present disclosure are applied.

[0112] Regarding scheduling and timing, DL and UL are frame aligned at the uplink time synchronization Reference Point (RP) with an offset given by NTA,offset.

[0113] To accommodate the propagation delay in NTNs, several timing relationships are enhanced by a Common Timing Advance (Common TA) and two offsets Koffsetand Kmac:

[0114] -Common TA is a configured timing offset that is equal to the Round Trip Timer (RTT) between the RP and the NTN payload.

[0115] - Koffsetis a configured scheduling offset that needs to be larger or equal to the sum of the service link RTT and the Common TA.

[0116] - Kmacis a configured offset that is approximately equal to the RTT between the RP and the gNB.

[0117] The scheduling offset Koffsetis used to allow the UE sufficient processing time between a downlink reception and an uplink transmission.

[0118] The offset Kmacis used to delay the application of a downlink configuration indicated by a MAC Control Element (CE) command on PDSCH, and in estimation of UE-gNB RTT. It may be provided by the network when downlink and uplink frame timing are not aligned at gNB. The Kmacis also used in the random access procedure, to determine the start time of RAR window / MsgB window after a Msg1 / MsgA transmission.

[0119] The network may configure the HARQ operation as follows:

[0120] - For downlink, HARQ feedback can be enabled or disabled per HARQ process. Disabling HARQ feedback allows scheduling a HARQ process before one HARQ RTT has elapsed since last scheduled.

[0121] - For uplink, HARQ mode (i.e., HARQ mode A or HARQ mode B) can be configured per HARQ process. HARQ mode B allows scheduling a HARQ process before one HARQ RTT has elapsed since last scheduled.

[0122] For the HARQ processes configured with HARQ feedback enabled / disabled, it is up to network implementation to ensure a proper configuration of HARQ feedback (e.g., either all enabled or all disabled) for HARQ processes used by a Semi-Persistent Scheduling (SPS) configuration. For the HARQ processes configured with HARQ mode, it is up to network implementation to ensure a proper configuration of HARQ mode (e.g., either all HARQ mode A or all HARQ mode B) for HARQ processes used by a Configured Grant (CG) configuration.

[0123] Regarding timing advance and frequency pre-compensation, for the serving cell, the network broadcast valid ephemeris information and Common TA parameters. The UE shall have valid Global Navigation Satellite System (GNSS) position as well as ephemeris and Common TA before connecting to an NTN cell. To achieve synchronization, before and during connection to an NTN cell, the UE shall compute the RTT between UE and the RP based on the GNSS position, the ephemeris, and the Common TA parameters, and autonomously pre-compensate the TTA for the RTT between the UE and the RP as illustrated in FIG. 9.

[0124] The UE shall compute the frequency Doppler shift of the service link, and autonomously pre-compensate for it in the uplink transmissions, by considering UE position and the ephemeris. If the UE does not have a valid GNSS position and / or valid ephemeris and Common TA, it shall not transmit until both are regained.

[0125] In connected mode, the UE shall be able to continuously update the Timing Advance and frequency pre-compensation.

[0126] The UE may be configured to report Timing Advance during Random Access procedures or in connected mode. In connected mode, event-triggered reporting of the Timing Advance is supported.

[0127] While the pre-compensation of the instantaneous Doppler shift experienced on the service link is to be performed by the UE, the management of Doppler shift experienced over the feeder link and transponder frequency error is left to the network implementation.

[0128] Mobility in RRC_CONNECTED for NTN may include a mobility procedure which may be called a satellite switch with re-synchronization. Upon both hard and soft satellite switch over in the quasi-Earth fixed scenario with the same SSB frequency and the same gNB, the satellite switch with re-synchronization procedure is supported. The satellite switch with re-synchronization avoids a L3 mobility for UEs in the cell by maintaining the same PCI on the geographical area covered by quasi-Earth fixed beam.

[0129] For soft satellite switch over, the UE can start synchronizing with the target satellite before the source satellite ends to serve the cell. It is not required for the UE to be connected to source satellite when the UE switches to target satellite.

[0130] For hard satellite switch over, the UE can only start synchronizing with the target satellite after the source satellite ends to serve the cell.

[0131] When both Conditional Handover (CHO) and Satellite switch with re-synchronization are configured, it is up to UE implementation which procedure to initiate, if both of them are triggered simultaneously.

[0132] For the re-synchronization to the target satellite, random access can be triggered by a PDCCH order via the target satellite.

[0133] As mentioned above, in NTN, there is a mobility procedure (e.g., satellite switch with re-synchronization) from a source satellite to a target satellite that the PCI does not change. In this mobility procedure, the UE may consider the source satellite to be changed to the target satellite at the time which is based on the timing information (e.g.,t-Service) provided by the network. When initiating this mobility procedure, the UE may just (re-)synchronize the layer 1 DL / UL synchronization while maintaining the current cell configuration. The timing information (e.g.,t-Service) may be provided to the UE via broadcasting signaling (e.g., SIB19).

[0134] If another timing information (e.g.,t-ServiceStart) is provided to the UE via broadcasting signaling (e.g., SIB19), the UE can softly re-synchronize with the target satellite (e.g., soft satellite switch with re-synchronization). The softly re-synchronizing may involve performing DL synchronization with the target satellite between thet-ServiceStartand thet-Service(i.e., early DL synchronization with the target satellite).

[0135] For example, a UE capable of hard satellite switch with resynchronization in RRC_CONNECTED may initiate the procedure whenSatSwitchWithReSyncandt-Serviceare included inSIB19.

[0136] Upon initiating the procedure, the UE shall:

[0137] 1> ift-ServiceStartis included inSIB19and the UE supports soft satellite switch with resynchronization:

[0138] 2> start acquiring DL synchronization with the SpCell served by the satellite indicated byntn-ConfiginSatSwitchWithReSyncbetween the time indicated byt-ServiceStartand the time indicated byt-Servicefor the serving cell;

[0139] 1> upon the time indicated byt-Service:

[0140] 2> stop timer T430 if running;

[0141] 2> inform lower layers that UL synchronization is lost due to satellite switch with resynchronization;

[0142] 2> synchronize to the DL of the SpCell served by the satellite indicated byntn-ConfiginSatSwitchWithReSync, if the UE has not previously synchronized to the DL of the SpCell;

[0143] 2> start timer T430 with the timer value set tontn-UlSyncValidityDurationfrom the subframe indicated byepochTimeinntn-ConfiginSatSwitchWithReSync;

[0144] 2> inform lower layers when UL synchronization is obtained.

[0145] The UE should attempt to re-acquireSIB19after satellite switch with resynchronization. The exact time is left to UE implementation.

[0146] The fieldsatSwitchWithReSyncprovides parameters for the target satellite required to perform satellite switch with resynchronization. This field is only present in an NTN cell and its presence indicates that satellite switch without PCI change is supported in the cell.

[0147] The fieldt-Serviceindicates the time information on when a cell provided via NTN is going to stop serving the area it is currently covering. This field applies for both service link switches in NTN quasi-Earth fixed cell and feeder link switches for both NTN quasi-Earth fixed and Earth-moving cell. The field indicates a time in multiples of 10 ms after 00:00:00 on Gregorian calendar date 1 January, 1900 (midnight between Sunday, December 31, 1899 and Monday, January 1, 1900). The exact stop time is between the time indicated by the value of this field minus 1 and the time indicated by the value of this field. The reference point fort-Serviceis the uplink time synchronization reference point of the cell. This field is only present in an NTN cell.

[0148] The fieldt-ServiceStartindicates the time information on when the target satellite is going to start serving the area currently covered by the serving satellite. The field indicates a time in multiples of 10ms after 00:00:00 on Gregorian calendar date 1st January 1900 (midnight between Sunday, December 31, 1899, and Monday, January 1, 1900). The exact start time is between the time indicated by the value of this field minus 1 and the time indicated by the value of this field. The reference point fort-ServiceStartis the uplink time synchronization reference point of the serving satellite.

[0149] Meanwhile, a timer-based mobility failure may not be supported for the satellite switch with re-synchronization. For example, a timer (e.g., T304) may not be used for the satellite switch with re-synchronization. If the layer 1 DL / UL synchronization fails, the UE may just declare a radio link failure due to the out-of-sync indication. However, the network cannot know if the Layer 1 DL / UL synchronization is succeeded but there was / were one or more temporarily out-of-sync indication that did not require the UE to declare the radio link failure due to the out-of-sync indication.

[0150] If the timing information is incorrectly configured due to mis-coordination between the source satellite and the target satellite, there may be a case where the UE succeeded the layer 1 DL / UL synchronization with the temporarily out-of-sync indication. Due to this reason, it would be beneficial for the network to optimize the timing configuration for the mobility procedure from a source satellite to a target satellite that the PCI does not change if the UE can report the temporarily out-of-sync indication even in the success case of the mobility.

[0151] According to implementations of the present disclosure, in order to determine a proper near failure of the unchanged PCI satellite mobility (e.g., satellite switch with re-synchronization), a new logging condition may be considered based on reception of a significant number of out-of-sync indications during the mobility.

[0152] According to implementations of the present disclosure, the UE may determine to perform logging of results of a DL and / or UL synchronization based on a logging condition received from the network and / or out-of-sync indication status. For example, if the logging condition is met based on considering the indicated number of out-of-sync indications, the UE may perform logging results of the DL and / or UL synchronization. The DL and / or UL synchronization may be time-based layer 1 DL and / or UL synchronization. The DL and / or UL synchronization may be used for a mobility procedure from a source satellite to a target satellite that the PCI does not change (e.g., satellite switch with re-synchronization).

[0153] According to implementations of the present disclosure, the network may provide a timing value for the DL and / or UL synchronization. The timing value may be used by the UE to determine when to perform DL and / or UL synchronization. When the time arrives based on the promised standard time between the UE and the network, the UE may perform DL and / or UL (re-)synchronization for data transmission with the network. The timing value may bet-Service.

[0154] According to implementations of the present disclosure, the logging condition may be a ratio threshold related to indicated number of out-of-sync indications during performing the time-based DL and / or UL synchronization. Or, the logging condition may be a count value.

[0155] For example, in case that the logging condition is the ratio threshold, the UE may check a ratio between indicated number of out-of-sync indications during the DL and / or UL synchronization and the maximum number of out-of-sync indications to declare a radio link failure. If the ratio is greater than the ratio threshold, the UE may consider that the logging condition is met. If one or more out-of-sync indications was / were being indicated before the DL and / or UL synchronization, the UE may consider the received number of out-of-sync indications before the DL and / or UL synchronization together with the number of out-of-sync indications during the time-based DL and / or UL synchronization when checking the ratio between the indicated number of out-of-sync indications and the maximum number of out-of-sync indication. Otherwise, the UE may not consider the received number of out-of-sync indications before the DL and / or UL synchronization. That is, the UE may initialize the number of out-of-sync indications before the DL and / or UL synchronization to zero to consider only the number of out-of-sync indications during the DL and / or UL synchronization.

[0156] For example, in case that the logging condition is the count value, the UE may check if the indicated number of out-of-sync indications during the DL and / or UL synchronization is greater than (and / or equal to) the count value. If the indicated number of out-of-sync indications is greater than (and / or equal to) the count value, the UE may consider that the logging condition is met. If one or more out-of-sync indication was / were being indicated before the DL and / or UL synchronization, the UE may consider the received number of out-of-sync indications before the DL and / or UL synchronization together with the number of out-of-sync indications during the time-based DL and / or UL synchronization when checking if the logging condition is met.

[0157] For example, in case that the logging condition is the count value, the UE may check if the indicated number of out-of-sync indications is same as the count value. If the indicated number of out-of-sync indications is below than the count value, the UE may consider that the logging condition is not met.

[0158] Alternatively, if the network does not provide the logging condition(s), the UE may not consider the logging condition and the UE may perform the logging for the DL and / or UL synchronization whenever performing the DL and / or UL synchronization.

[0159] According to implementations of the present disclosure, when performing logging results of the DL and / or UL synchronization, at least one of the following information may be optionally logged:

[0160] 1) Actual initiation time of the DL and / or UL synchronization; and / or

[0161] 2) Timing of the DL and / or UL synchronization provided from the network (e.g.,t-Service), and / or

[0162] 3) Timing of early initiation of the DL and / or UL synchronization provided from the network (e.g.,t-ServiceStart): This time information allows the UE to perform DL and / or UL synchronization more quickly than t-Service (e.g., soft DL and / or UL synchronization). This time information indicates that the target satellite is already in the area where it will soon provide service; and / or

[0163] 4) The indicated number of out-of-sync indications: If one or more out-of-sync indications occurred before the DL and / or UL synchronization, the out-of-sync indications occurred before the DL and / or UL synchronization and the out-of-sync indications occurred during the DL and / or UL synchronization may be merged. That is, the indicated number of out-of-sync indications may include the out-of-sync indications occurred before the DL and / or UL synchronization and the out-of-sync indications occurred during the DL and / or UL synchronization. Alternatively, the UE may report the number of out-of-sync indications occurred before the DL and / or UL synchronization separately from the number of out-of-sync indications during the DL and / or UL synchronization.

[0164] According to implementations of the present disclosure, if the number of out-of-sync indications meets the condition for declaring a radio link failure (e.g., reaches the maximum number of out-of-sync indications), the UE may declare a radio link failure and may perform radio link failure logging (e.g., RLF-report) regardless of the logging conditions being met or not. When performing the radio link failure logging, the UE may include the above information related to the DL and / or UL synchronization.

[0165] According to implementations of the present disclosure, the UE may use the existing reporting information (e.g.,successHO-Report(SHR) orMobilityHistoryReport(MHR)) to report to the network. If the network does not provide the logging condition, the UE may report the logging results based on the existing logging condition of the existing logging procedure (e.g., existing logging conditions of SHR).

[0166] According to implementations of the present disclosure, each time the UE establishes an RRC connection, the UE may check if the security information has been logged. During the (re)establishment and / or resumption of the RRC connection, the UE may notify the network of an availability of the logging or report the logging results. If the UE is (re)establishing the RRC connection, the UE may first inform the network of the availability via RRC signaling. If the UE is resuming the suspended RRC connection, the UE may directly report the logging results related to the security information to the network via RRC signaling.

[0167] According to implementations of the present disclosure, the UE may also report the logging information to the network while maintaining the RRC connection. In this case, the UE may notify the network of the availability or directly report the logging results in the RRC message sent as a response to a received RRC message from the network.

[0168] The following drawings are created to explain specific embodiments of the present disclosure. The names of the specific devices or the names of the specific signals / messages / fields shown in the drawings are provided by way of example, and thus the technical features of the present disclosure are not limited to the specific names used in the following drawings.

[0169] An embodiment of the present disclosure related to a specific drawing described below may be combined with various embodiments of the present disclosure related to other drawings, and some descriptions, functions, procedures, proposals, methods and / or operations of the embodiment may be omitted.

[0170] FIG. 10 shows an example of a method to which implementations of the present disclosure are applied.

[0171] In step S1000, the method comprises receiving time information from a network.

[0172] In step S1010, the method comprises receiving a logging condition from the network.

[0173] In step S1020, the method comprises performing DL / UL synchronization based on the time information.

[0174] In step S1030, the method comprises logging results of the DL / UL synchronization based on the logging condition being met.

[0175] In step S1040, the method comprises reporting the results of the DL / UL synchronization to the network.

[0176] In some implementations, the logging condition may include a ratio threshold. For example, the logging condition may be met based on a ratio of the number of out-of-sync indications and a maximum number of out-of-sync indications being greater than the ratio threshold.

[0177] In some implementations, the number of out-of-sync indications may include the number of out-of-sync indications during the DL / UL synchronization and the number of out-of-sync indications before the DL / UL synchronization.

[0178] Or, the number of out-of-sync indications may include only the number of out-of-sync indications during the DL / UL synchronization, and does not include the number of out-of-sync indications before the DL / UL synchronization. In this case, the number of out-of-sync indications may be initialized to zero before the DL / UL synchronization.

[0179] In some implementations, the logging condition may include a count value. For example, the logging condition may be met based on the number of out-of-sync indications being greater than the count value.

[0180] In some implementations, the results of the DL / UL synchronization may include at least one of i) an actual initiation time of the DL / UL synchronization, ii) a timing of the DL / UL synchronization provided from the network, iii) a timing of early initiation of the DL / UL synchronization provided from the network, iv) the number of out-of-sync indications, and / or v) an availability of the results of the DL / UL synchronization.

[0181] In some implementations, the DL / UL synchronization may be related to a satellite switch without PCI change.

[0182] In some implementations, the DL / UL synchronization may include time-based DL / UL synchronization.

[0183] In some implementations, the time information and / or the logging condition may be received from a source satellite, and the results of the DL / UL synchronization may be reported to a target satellite.

[0184] In some implementations, the time information may be used to determine when to perform the DL / UL synchronization.

[0185] In some implementations, the time information includes at least one oft-Service, and / ort-ServiceStart.

[0186] In some implementations, the method may further comprise declaring a radio link failure and perform radio link failure logging, based on the number of out-of-sync indications satisfying a condition for declaring the radio link failure regardless of the logging condition. For example, the radio link failure logging may include logging of results of the DL / UL synchronization.

[0187] In some implementations, the results of the DL / UL synchronization may be reported based on an SHR and / or an MHR.

[0188] In some implementations, the results of the DL / UL synchronization may be reported during establishment, re-establishment and / or resumption of an RRC connection with the network.

[0189] In some implementations, the method is performed by a wireless device in communication with at least one of a mobile device, a network, and / or autonomous vehicles other than the wireless device.

[0190] For example, the results of the DL / UL synchronization may be reported by the following procedures.

[0191] The UE information procedure is used by the network to request the UE to report information.

[0192] The network initiates the procedure by sending theUEInformationRequestmessage. The network should initiate this procedure only after successful security activation.

[0193] Upon receiving theUEInformationRequestmessage, the UE shall, only after successful security activation:

[0194] ...

[0195] 1> ifrlf-ReportReqis set totrue:

[0196] 2> if the UE has radio link failure information or handover failure information available inVarRLF-Reportand if the RPLMN is included inplmn-IdentityListstored inVarRLF-Report; or

[0197] 2> if the UE has radio link failure information or handover failure information available inVarRLF-Reportand if the current registered SNPN identity is included insnpn-IdentityListstored inVarRLF-Report:

[0198] 3> settimeSinceFailureinVarRLF-Reportto the time that elapsed since the last radio link failure or handover failure in NR;

[0199] 3> set therlf-Reportin theUEInformationResponsemessage to the value ofrlf-ReportinVarRLF-Report;

[0200] 3> discard therlf-ReportfromVarRLF-Reportupon successful delivery of theUEInformationResponsemessage confirmed by lower layers;

[0201] ...

[0202] 1> ifconnEstFailReportReqis set totrueand the UE has connection establishment failure or connection resume failure information inVarConnEstFailReportorVarConnEstFailReportListand if the RPLMN is equal toplmn-Identitystored inVarConnEstFailReportorin at least one of the entries ofVarConnEstFailReportList:

[0203] 1> ifconnEstFailReportReqis set totrueand if the UE has connection establishment failure information or connection resume failure information available inVarConnEstFailReportorVarConnEstFailReportListand if the registered SNPN identity is equal tosnpn-identityinnetworkIdentitystored inVarConnEstFailReportor any entry ofVarConnEstFailReportList:

[0204] 2> settimeSinceFailureinVarConnEstFailReportto the time that elapsed since the last connection establishment failure or connection resume failure in NR;

[0205] 2> set theconnEstFailReportin theUEInformationResponsemessage to the value ofconnEstFailReportinVarConnEstFailReport;

[0206] 2> if the UE supports multiple CEF report:

[0207] 3> for eachconnEstFailReportin theconnEstFailReportListinVarConnEstFailReportList:

[0208] 4> settimeSinceFailureto the time that elapsed since the associated connection establishment failure or connection resume failure in NR;

[0209] 2> for eachconnEstFailReportin theconnEstFailReportListin theUEInformationResponsemessage, set the value to the value ofconnEstFailReportinVarConnEstFailReportinVarConnEstFailReportList;

[0210] 2> discard theconnEstFailReportfromVarConnEstFailReportandVarConnEstFailReportListupon successful delivery of theUEInformationResponsemessage confirmed by lower layers;

[0211] 1> if themobilityHistoryReportReqis set totrue:

[0212] 2> include themobilityHistoryReportand set it to includevisitedCellInfoListfromVarMobilityHistoryReport;

[0213] 2> include in themobilityHistoryReportan entry for the current PCell, possibly after removing the oldest entry if required, and set its fields as follows:

[0214] 3> setvisitedCellIdto the global cell identity or the physical cell identity and carrier frequency of the current PCell:

[0215] 3> set fieldtimeSpentto the time spent in the current PCell;

[0216] 3> if the UE supports PSCell mobility history information and ifvisitedPSCellInfoListis present inVarMobilityHistoryReport:

[0217] 4> for the newest entry of the PCell in themobilityHistoryReport, includevisitedPSCellInfoListfromVarMobilityHistoryReport;

[0218] 4> if the UE is configured with a PSCell:

[0219] 5> for the newest entry of the PCell in themobilityHistoryReport, include the current PSCell information in thevisitedPSCellInfoListReport,possibly after removing the oldest PSCell entry of a PCell in themobilityHistoryReport, if required, and set its fields as follows:

[0220] 6> setvisitedCellIdto the global cell identity or the physical cell identity and carrier frequency of the current PSCell:

[0221] 6> set fieldtimeSpentto the time spent in the current PSCell while being connected to the current PCell;

[0222] 4> else:

[0223] 5> for the newest entry of the PCell in themobilityHistoryReport, include a new entry in thevisitedPSCellInfoListReport,possibly after removing the oldest PSCell entry of a PCell in themobilityHistoryReport, if required, and set its fields as follows:

[0224] 6> set fieldtimeSpentto the time spent without PSCell in the current PCell since last PSCell release since connected to the current PCell in RRC_CONNECTED;

[0225] 3> else if the UE supports PSCell mobility history information:

[0226] 4> if the UE is configured with a PSCell:

[0227] 5> for the newest entry of the PCell in themobilityHistoryReport, include the current PSCell information in thevisitedPSCellInfoListReport,possibly after removing the oldest PSCell entry of a PCell in themobilityHistoryReport, if required, and set its fields as follows:

[0228] 6> setvisitedCellIdto the global cell identity or the physical cell identity and carrier frequency of the current PSCell:

[0229] 6> set fieldtimeSpentto the time spent in the current PSCell while being connected to the current PCell;

[0230] 4> else:

[0231] 5> for the newest entry of the PCell in themobilityHistoryReport, include a new entry in thevisitedPSCellInfoListReport,possibly after removing the oldest PSCell entry of a PCell in themobilityHistoryReport, if required, and set its fields as follows:

[0232] 6> set fieldtimeSpentto the time spent without PSCell in the current PCell since connected to the current PCell in RRC_CONNECTED;

[0233] 1> if thesuccessHO-ReportReqis set totrueand if the UE has successful handover related information available inVarSuccessHO-Reportand if the RPLMN is included in theplmn-IdentityListstored inVarSuccessHO-Report; or

[0234] 1> if thesuccessHO-ReportReqis set totrueand if the UE has successful handover related information available inVarSuccessHO-Reportand if the current registered SNPN identity is included insnpn-IdentityListif stored in theVarSuccessHO-Report:

[0235] 2> if thesuccessHO-Reportin theVarSuccessHO-Reportconcerns a DAPS handover and if a PDCP PDU has been received from the source cell of the concerned HO and a non-duplicated PDCP PDU has been received from the target cell of the concerned HO:

[0236] 3> setupInterruptionTimeAtHOinVarSuccessHO-Reportto include the time elapsed between the time of arrival of the last PDCP PDU received from the source cell of the concerned handover and the time of arrival of the first non-duplicate PDCP PDU received from the target cell of the concerned handover, as measured at the time of arrival of the first non-duplicate PDCP PDU received from the target cell;

[0237] 2> if thesuccessHO-Reportin theVarSuccessHO-Reportconcerns amobilityFromNRCommand:

[0238] 3> settimeSinceSHRinVarSuccessHO-Reportto the time that elapsed since the successful handover report determination;

[0239] 2> set thesuccessHO-Reportin theUEInformationResponsemessage to the value ofsuccessHO-Reportin theVarSuccessHO-Report, if available;

[0240] 2> discard theVarSuccessHO-Reportupon successful delivery of theUEInformationResponsemessage confirmed by lower layers;

[0241] 1> if thesuccessPSCell-ReportReqis set totrueand if the UE has successful PSCell change or addition information available inVarSuccessPSCell-Reportand if the RPLMN is included inplmn-IdentityListstored inVarSuccessPSCell-Report; or

[0242] 1> if thesuccessPSCell-ReportReqis set totrueand if the UE has successful PSCell change or addition information available inVarSuccessPSCell-Reportand if the current registered SNPN identity is included insnpn-IdentityListif stored in theVarSuccessPSCell-Report:

[0243] 2> set thesuccessPSCell-Reportin theUEInformationResponsemessage to the value ofsuccessPSCell-Reportin theVarSuccessPSCell-Report;

[0244] 2> discard theVarSuccessPSCell-Reportupon successful delivery of theUEInformationResponsemessage confirmed by lower layers;

[0245] ...

[0246] 1> if thelogMeasReportis included in theUEInformationResponse:

[0247] 2> submit theUEInformationResponsemessage to lower layers for transmission via SRB2;

[0248] 2> discard the logged measurement entries included in thelogMeasInfoListfromVarLogMeasReportupon successful delivery of theUEInformationResponsemessage confirmed by lower layers;

[0249] 1> else:

[0250] 2> submit theUEInformationResponsemessage to lower layers for transmission via SRB1.

[0251] Furthermore, the wireless device may be implemented by the first wireless device 100 shown in FIG. 2 and / or the UE 100 shown in FIG. 3.

[0252] The wireless device comprises at least one transceiver, at least one processor, and at least one memory operably connectable to the at least one processor and storing instructions that, based on being executed by the at least one processor, cause the wireless device to perform the method described in FIG. 10.

[0253] More specifically, the wireless device receives time information from a network.

[0254] The wireless device receives a logging condition from the network.

[0255] The wireless device performs DL / UL synchronization based on the time information.

[0256] The wireless device logs results of the DL / UL synchronization based on the logging condition being met.

[0257] The wireless device reports the results of the DL / UL synchronization to the network.

[0258] In some implementations, the logging condition may include a ratio threshold. For example, the logging condition may be met based on a ratio of the number of out-of-sync indications and a maximum number of out-of-sync indications being greater than the ratio threshold.

[0259] In some implementations, the number of out-of-sync indications may include the number of out-of-sync indications during the DL / UL synchronization and the number of out-of-sync indications before the DL / UL synchronization.

[0260] Or, the number of out-of-sync indications may include only the number of out-of-sync indications during the DL / UL synchronization, and does not include the number of out-of-sync indications before the DL / UL synchronization. In this case, the number of out-of-sync indications may be initialized to zero before the DL / UL synchronization.

[0261] In some implementations, the logging condition may include a count value. For example, the logging condition may be met based on the number of out-of-sync indications being greater than the count value.

[0262] In some implementations, the results of the DL / UL synchronization may include at least one of i) an actual initiation time of the DL / UL synchronization, ii) a timing of the DL / UL synchronization provided from the network, iii) a timing of early initiation of the DL / UL synchronization provided from the network, iv) the number of out-of-sync indications, and / or v) an availability of the results of the DL / UL synchronization.

[0263] In some implementations, the DL / UL synchronization may be related to a satellite switch without PCI change.

[0264] In some implementations, the DL / UL synchronization may include time-based DL / UL synchronization.

[0265] In some implementations, the time information and / or the logging condition may be received from a source satellite, and the results of the DL / UL synchronization may be reported to a target satellite.

[0266] In some implementations, the time information may be used to determine when to perform the DL / UL synchronization.

[0267] In some implementations, the time information includes at least one oft-Service, and / ort-ServiceStart.

[0268] In some implementations, the wireless device may declare a radio link failure and perform radio link failure logging, based on the number of out-of-sync indications satisfying a condition for declaring the radio link failure regardless of the logging condition. For example, the radio link failure logging may include logging of results of the DL / UL synchronization.

[0269] In some implementations, the results of the DL / UL synchronization may be reported based on an SHR and / or an MHR.

[0270] In some implementations, the results of the DL / UL synchronization may be reported during establishment, re-establishment and / or resumption of an RRC connection with the network.

[0271] Furthermore, the method described above in FIG. 10 may be performed by control of a processing apparatus. The processing apparatus may be implemented by the processor 102 included in the first wireless device 100 shown in FIG. 2 and / or the processor 102 included in the UE 100 shown in FIG. 3.

[0272] The processing apparatus comprises at least one processor that is integrated with a wireless device, and at least one memory comprising processor-executable instructions stored thereon that are configured to cause the at least one processor to perform the method described in FIG. 10.

[0273] Furthermore, the method described above in FIG. 10 may be performed by a software code 105 stored in the memory 104 included in the first wireless device 100 shown in FIG. 2.

[0274] The technical features of the present disclosure may be embodied directly in hardware, in a software executed by a processor, or in a combination of the two. For example, a method performed by a wireless device in a wireless communication may be implemented in hardware, software, firmware, or any combination thereof. For example, a software may reside in RAM, flash memory, ROM, EPROM, EEPROM, registers, hard disk, a removable disk, a CD-ROM, or any other storage medium.

[0275] Some example of storage medium may be coupled to the processor such that the processor can read information from the storage medium. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC. For other example, the processor and the storage medium may reside as discrete components.

[0276] The computer-readable medium may include a tangible and non-transitory computer-readable storage medium.

[0277] For example, non-transitory computer-readable media may include RAM such as Synchronous DRAM (SDRAM), ROM, Non-Volatile RAM (NVRAM), EEPROM, flash memory, magnetic or optical data storage media, or any other medium that can be used to store instructions or data structures. Non-transitory computer-readable media may also include combinations of the above.

[0278] In addition, the method described herein may be realized at least in part by a computer-readable communication medium that carries or communicates code in the form of instructions or data structures and that can be accessed, read, and / or executed by a computer.

[0279] According to some implementations of the present disclosure, a non-transitory Computer-Readable Medium (CRM) stores instructions that, based on being executed by at least one processor, perform the method described in FIG. 10.

[0280] FIG. 11 shows an example of another method to which implementations of the present disclosure are applied.

[0281] In step S1100, the method comprises transmitting time information to a wireless device, wherein DL / UL synchronization is performed based on the time information.

[0282] In step S1110, the method comprises transmitting a logging condition to the wireless device.

[0283] In step S1120, the method comprises receiving logging results of the DL / UL synchronization from the wireless device based on the logging condition being met.

[0284] Furthermore, the method described above in FIG. 11 may be performed by a base station. The base station may be implemented by the second wireless device 200 shown in FIG. 2.

[0285] The base station comprises at least one transceiver, at least one processor, and at least one memory operably connectable to the at least one processor and storing instructions that, based on being executed by the at least one processor, cause the base station to perform the method described in FIG. 11.

[0286] More specifically, the base station transmits time information to a wireless device, wherein DL / UL synchronization is performed based on the time information.

[0287] The base station transmits a logging condition to the wireless device.

[0288] The base station receives logging results of the DL / UL synchronization from the wireless device based on the logging condition being met.

[0289] The present disclosure may have various advantageous effects.

[0290] For example, the network can know the situation where the UE succeeded the layer 1 DL / UL synchronization with the temporarily out-of-sync indication. Thus, the network can optimize the time configuration for the mobility to prevent the temporarily out-of-sync indication in the future.

[0291] 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.

[0292] 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 time information from a network;receiving a logging condition from the network;performing downlink (DL) / uplink (UL) synchronization based on the time information;logging results of the DL / UL synchronization based on the logging condition being met; andreporting the results of the DL / UL synchronization to the network.2.The method of claim 1, wherein the logging condition includes a ratio threshold.3.The method of claim 2, wherein the logging condition is met based on a ratio of the number of out-of-sync indications and a maximum number of out-of-sync indications being greater than the ratio threshold.4.The method of claim 2 or 3, wherein the number of out-of-sync indications includes the number of out-of-sync indications during the DL / UL synchronization and the number of out-of-sync indications before the DL / UL synchronization.5.The method of claim 2 or 3, wherein the number of out-of-sync indications includes only the number of out-of-sync indications during the DL / UL synchronization, and does not include the number of out-of-sync indications before the DL / UL synchronization.6.The method of claim 5, wherein the number of out-of-sync indications is initialized to zero before the DL / UL synchronization.7.The method of claim 1, wherein the logging condition includes a count value.8.The method of claim 7, wherein the logging condition is met based on the number of out-of-sync indications being greater than the count value.9.The method of any claims 1 to 8, wherein the results of the DL / UL synchronization include at least one of i) an actual initiation time of the DL / UL synchronization, ii) a timing of the DL / UL synchronization provided from the network, iii) a timing of early initiation of the DL / UL synchronization provided from the network, iv) the number of out-of-sync indications, and / or v) an availability of the results of the DL / UL synchronization.10.The method of any claims 1 to 9, wherein the DL / UL synchronization is related to a satellite switch without physical Cell Identity (PCI) change.11.The method of any claims 1 to 10, wherein the DL / UL synchronization includes time-based DL / UL synchronization.12.The method of any claims 1 to 11, wherein the time information and / or the logging condition is received from a source satellite, andwherein the results of the DL / UL synchronization are reported to a target satellite.13.The method of any claims 1 to 12, wherein the time information is used to determine when to perform the DL / UL synchronization.14.The method of any claims 1 to 13, wherein the time information includes at least one oft-Service, and / ort-ServiceStart.15.The method of any claims 1 to 14, wherein the method further comprises declaring a radio link failure and perform radio link failure logging, based on the number of out-of-sync indications satisfying a condition for declaring the radio link failure regardless of the logging condition.16.The method of claim 15, wherein the radio link failure logging includes logging of results of the DL / UL synchronization.17.The method of any claims 1 to 16, wherein the results of the DL / UL synchronization are reported based on a successful handover report (SHR) and / or a mobility history report (MHR).18.The method of any claims 1 to 16, wherein the results of the DL / UL synchronization are reported during establishment, re-establishment and / or resumption of a radio resource control (RRC) connection with the network.19.The method of any claims 1 to 18, wherein the method is performed by a wireless device in communication with at least one of a mobile device, a network, and / or autonomous vehicles other than the wireless device.20.A wireless device comprising:at least one transceiver;at least one processor; andat least one memory operably connectable to the at least one processor and storing instructions that, based on being executed by the at least one processor, cause the wireless device to perform the method of any claims 1 to 19.21.A processing apparatus comprising:at least one processor that is integrated with a wireless device; andat least one memory comprising processor-executable instructions stored thereon that are configured to cause the at least one processor to perform the method of any claims 1 to 19.22.A non-transitory Computer Readable Medium (CRM) storing instructions that, based on being executed by at least one processor, perform the method of any claims 1 to 19.23.A method comprising:transmitting time information to a wireless device, wherein DL / UL synchronization is performed based on the time information;transmitting a logging condition to the wireless device; andreceiving logging results of the DL / UL synchronization from the wireless device based on the logging condition being met.24.A base station comprising:at least one transceiver;at least one processor; andat least one memory operably connectable to the at least one processor and storing instructions that, based on being executed by the at least one processor, cause the base station to perform the method of claim 23.

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