Connection recovery in wireless communications

Abstract

The present disclosure is related to connection recovery in wireless communications. According to an embodiment of the present disclosure, a method performed by a communication device adapted to operate in a wireless communication system comprises: receiving information for a zone, and information for one or more frequencies related to the zone; identifying a current position of the communication device; and based on i) the current position of the communication device belonging to the zone, and ii) a serving frequency for the communication device being included in the one or more frequencies related to the zone, switching to a cell on a frequency other than the one or more frequencies related to the zone.

Description

CONNECTION RECOVERY IN WIRELESS COMMUNICATIONS

[0001] The present disclosure is related to connection recovery in wireless communications.

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

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

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

[0005] In wireless communications, there may be many cases where a communication device needs to perform connection recovery. For example, the communication device needs to perform connection recovery when detecting a failure (e.g., radio link failure, beam failure, or other types of failure) on a serving cell / frequency. Additionally, in addition to failure, the communication device can perform recovery procedures in various cases.

[0006] An aspect of the present disclosure is to provide method and apparatus for connection recovery in a wireless communication system.

[0007] According to an embodiment of the present disclosure, a method performed by a communication device adapted to operate in a wireless communication system comprises: receiving information for a zone, and information for one or more frequencies related to the zone; identifying a current position of the communication device; and based on i) the current position of the communication device belonging to the zone, and ii) a serving frequency for the communication device being included in the one or more frequencies related to the zone, switching to a cell on a frequency other than the one or more frequencies related to the zone.

[0008] According to an embodiment of the present disclosure, a method performed by a network node configured to operate in a wireless communication system comprises: transmitting, to a communication device, information for a zone, and information for one or more frequencies related to the zone, wherein the communication device is configured to perform operations comprising: identifying a current position of the communication device; and based on i) the current position of the communication device belonging to the zone, and ii) a serving frequency for the communication device being included in the one or more frequencies related to the zone, switching to a cell on a frequency other than the one or more frequencies related to the zone.

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

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

[0011] For example, even if UE enters a zone and the UE's serving frequency is affected by the zone where the frequency cannot be used for communication, the UE may perform a recovery procedure so that long service interruption or communication deadlock in the zone can be avoided.

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

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

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

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

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

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

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

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

[0020] FIG. 9 shows an example of a method performed by a communication device for recovery procedure according to an embodiment of the present disclosure.

[0021] FIG. 10 shows an example of a signal flow between a communication device and a network node for a recovery procedure according to an embodiment of the present disclosure.

[0022] FIG. 11 show an example of a method for triggering a connection recovery upon entering a special zone according to an embodiment of the present disclosure.

[0023] FIG. 12 shows an example of declaration of RLF upon entering NTZ affecting the PCell according to an embodiment of the present disclosure.

[0024] FIG. 13 shows an example of declaration of MCG RLF upon entering NTZ affecting the MCG according to an embodiment of the present disclosure.

[0025] FIG. 14 shows an example of declaration of SCG RLF upon entering NTZ affecting the SCG according to an embodiment of the present disclosure.

[0026] FIG. 15 shows an example of declaration of serving cell failure upon entering NTZ affecting a SCell according to an embodiment of the present disclosure.

[0027] The following techniques, apparatuses, and systems may be applied to a variety of wireless multiple access systems. Examples of the multiple access systems include a Code Division Multiple Access (CDMA) system, a Frequency Division Multiple Access (FDMA) system, a Time Division Multiple Access (TDMA) system, an Orthogonal Frequency Division Multiple Access (OFDMA) system, a Single Carrier Frequency Division Multiple Access (SC-FDMA) system, and a Multi Carrier Frequency Division Multiple Access (MC-FDMA) system. CDMA may be embodied through radio technology such as Universal Terrestrial Radio Access (UTRA) or CDMA2000. TDMA may be embodied through radio technology such as Global System for Mobile communications (GSM), General Packet Radio Service (GPRS), or Enhanced Data rates for GSM Evolution (EDGE). OFDMA may be embodied through radio technology such as Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, or Evolved UTRA (E-UTRA). UTRA is a part of a Universal Mobile Telecommunications System (UMTS). 3rd Generation Partnership Project (3GPP) Long-Term Evolution (LTE) is a part of Evolved UMTS (E-UMTS) using E-UTRA. 3GPP LTE employs OFDMA in downlink (DL) and SC-FDMA in uplink (UL). Evolution of 3GPP LTE includes LTE-Advanced (LTE-A), LTE-A Pro, and / or 5G New Radio (NR).

[0028] 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.

[0029] 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.

[0030] 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".

[0031] 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".

[0032] 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".

[0033] 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".

[0034] 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".

[0035] Technical features that are separately described in one drawing in the present disclosure may be implemented separately or simultaneously.

[0036] 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.

[0037] 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.

[0038] FIG. 1 shows an example of a communication system to which implementations of the present disclosure is applied.

[0039] 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.

[0040] 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).

[0041] 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.

[0042] 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.

[0043] 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.

[0044] 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.

[0045] 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.

[0046] 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.

[0047] 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.

[0048] 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).

[0049] Frequency Range designationCorresponding frequency rangeSubcarrier SpacingFR1450MHz - 6000MHz15, 30, 60kHzFR224250MHz - 52600MHz60, 120, 240kHz

[0050] 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).

[0051] Frequency Range designationCorresponding frequency rangeSubcarrier SpacingFR1410MHz - 7125MHz15, 30, 60kHzFR224250MHz - 52600MHz60, 120, 240kHz

[0052] Here, the radio communication technologies implemented in the wireless devices in the present disclosure may include NarrowBand IoT (NB-IoT) technology for low-power communication as well as LTE, NR and 6G. For example, NB-IoT technology may be an example of Low Power Wide Area Network (LPWAN) technology, may be implemented in specifications such as LTE Cat NB1 and / or LTE Cat NB2, and may not be limited to the above-mentioned names. Additionally and / or alternatively, the radio communication technologies implemented in the wireless devices in the present disclosure may communicate based on LTE-M technology. For example, LTE-M technology may be an example of LPWAN technology and be called by various names such as enhanced MTC (eMTC). For example, LTE-M technology may be implemented in at least one of the various specifications, such as 1) LTE Cat 0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTE non-bandwidth limited (non-BL), 5) LTE-MTC, 6) LTE Machine Type Communication, and / or 7) LTE M, and may not be limited to the above-mentioned names. Additionally and / or alternatively, the radio communication technologies implemented in the wireless devices in the present disclosure may include at least one of ZigBee, Bluetooth, and / or LPWAN which take into account low-power communication, and may not be limited to the above-mentioned names. For example, ZigBee technology may generate Personal Area Networks (PANs) associated with small / low-power digital communication based on various specifications such as IEEE 802.15.4 and may be called various names.FIG. 2 shows an example of wireless devices to which implementations of the present disclosure is applied.

[0053] 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.

[0054] 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.

[0055] 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.

[0056] 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.

[0057] 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.

[0058] 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.

[0059] 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.

[0060] 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.

[0061] 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.

[0062] 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.

[0063] 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.

[0064] 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.

[0065] 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.

[0066] 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.

[0067] 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.

[0068] 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).

[0069] 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.

[0070] 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.

[0071] In the implementations of the present disclosure, a UE may operate as a transmitting device in Uplink (UL) and as a receiving device in Downlink (DL). In the implementations of the present disclosure, a BS may operate as a receiving device in UL and as a transmitting device in DL. Hereinafter, for convenience of description, it is mainly assumed that the first wireless device 100 acts as the UE, and the second wireless device 200 acts as the BS. For example, the processor(s) 102 connected to, mounted on or launched in the first wireless device 100 may be adapted to perform the UE behavior according to an implementation of the present disclosure or control the transceiver(s) 106 to perform the UE behavior according to an implementation of the present disclosure. The processor(s) 202 connected to, mounted on or launched in the second wireless device 200 may be adapted to perform the BS behavior according to an implementation of the present disclosure or control the transceiver(s) 206 to perform the BS behavior according to an implementation of the present disclosure.

[0072] In the present disclosure, a BS is also referred to as a node B (NB), an eNode B (eNB), or a gNB.

[0073] FIG. 3 shows an example of UE to which implementations of the present disclosure is applied.

[0074] Referring to FIG. 3, a UE 100 may correspond to the first wireless device 100 of FIG. 2.

[0075] 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.

[0076] 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.

[0077] 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.

[0078] 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.

[0079] 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.

[0080] 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.

[0081] 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.

[0082] 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.

[0083] FIGs. 4 and 5 show an example of protocol stacks in a 3GPP based wireless communication system to which implementations of the present disclosure is applied.

[0084] In particular, FIG. 4 illustrates an example of a radio interface user plane protocol stack between a UE and a BS and FIG. 5 illustrates an example of a radio interface control plane protocol stack between a UE and a BS. The control plane refers to a path through which control messages used to manage call by a UE and a network are transported. The user plane refers to a path through which data generated in an application layer, for example, voice data or Internet packet data are transported. Referring to FIG. 4, the user plane protocol stack may be divided into Layer 1 (L1, for example PHY layer) and Layer 2 (L2, for example MAC / RLC / PDCP layer). Referring to FIG. 5, the control plane protocol stack may be divided into Layer 1 (L1, for example PHY layer), Layer 2 (L2, for example MAC / RLC / PDCP layer), Layer 3 (L3, for example an RRC layer), and a non-access stratum (NAS) layer. Layer 1, Layer 2 and Layer 3 are referred to as an access stratum (AS).

[0085] 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.

[0086] 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.

[0087] 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.

[0088] The RLC sublayer supports three transmission modes: transparent mode (TM), unacknowledged mode (UM), and acknowledged node (AM). The RLC configuration is per logical channel with no dependency on numerologies and / or transmission durations. In the 3GPP NR system, the main services and functions of the RLC sublayer depend on the transmission mode and include: transfer of upper layer PDUs; sequence numbering independent of the one in PDCP (UM and AM); error correction through ARQ (AM only); segmentation (AM and UM) and re-segmentation (AM only) of RLC SDUs; reassembly of SDU (AM and UM); duplicate detection (AM only); RLC SDU discard (AM and UM); RLC re-establishment; protocol error detection (AM only).

[0089] 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.

[0090] 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.

[0091] In the 3GPP NR system, the main services and functions of the RRC sublayer include: broadcast of system information related to AS and NAS; paging initiated by 5GC or NG-RAN; establishment, maintenance and release of an RRC connection between the UE and NG-RAN; security functions including key management; establishment, configuration, maintenance and release of 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.

[0092] FIG. 6 shows a frame structure in a 3GPP based wireless communication system to which implementations of the present disclosure is applied.

[0093] The frame structure shown in FIG. 6 is purely exemplary and the number of subframes, the number of slots, and / or the number of symbols in a frame may be variously changed. In the 3GPP based wireless communication system, OFDM numerologies (e.g., subcarrier spacing (SCS), transmission time interval (TTI) duration) may be differently configured between a plurality of cells aggregated for one UE. For example, if a UE is configured with different SCSs for cells aggregated for the cell, an (absolute time) duration of a time resource (e.g., a subframe, a slot, or a TTI) including the same number of symbols may be different among the aggregated cells. Herein, symbols may include OFDM symbols (or CP-OFDM symbols), SC-FDMA symbols (or discrete Fourier transform-spread-OFDM (DFT-s-OFDM) symbols).

[0094] Referring to FIG. 6, downlink and uplink transmissions are organized into frames. Each frame has Tf= 10ms duration. Each frame is divided into two half-frames, where each of the half-frames has 5ms duration. Each half-frame consists of 5 subframes, where the duration Tsfper subframe is 1ms. Each subframe is divided into slots and the number of slots in a subframe depends on a subcarrier spacing. Each slot includes 14 or 12 OFDM symbols based on a cyclic prefix (CP). In a normal CP, each slot includes 14 OFDM symbols and, in an extended CP, each slot includes 12 OFDM symbols. The numerology is based on exponentially scalable subcarrier spacing βf = 2u*15 kHz.

[0095] 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 βf = 2u*15 kHz.

[0096] uNslotsymbNframe,uslotNsubframe,uslot01410111420221440431480841416016

[0097] 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 βf = 2u*15 kHz.

[0098] uNslotsymbNframe,uslotNsubframe,uslot212404

[0099] 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. As shown in FIG. 6, as SCS doubles, the slot length and symbol length are halved. For example, when SCS is 15kHz, the slot length is 1ms, which is the same as the subframe length. When SCS is 30kHz, the slot length is 0.5ms (=500us), and the symbol length is half of that when the SCS is 15kHz. When SCS is 60kHz, the slot length is 0.25ms (=250us), and the symbol length is half of that when the SCS is 30kHz. When SCS is 120kHz, the slot length is 0.125ms (=125us), and the symbol length is half of that when the SCS is 60kHz. When SCS is 240kHz, the slot length is 0.0625ms (=62.5us), and the symbol length is half of that when the SCS is 120kHz.

[0100] 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.

[0101] 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.

[0102] In CA, two or more CCs are aggregated. A UE may simultaneously receive or transmit on one or multiple CCs depending on its capabilities. CA is supported for both contiguous and non-contiguous CCs. When CA is configured, the UE only has one RRC connection with the network. At RRC connection establishment / re-establishment / handover, one serving cell provides the NAS mobility information, and at RRC connection re-establishment / handover, one serving cell provides the security input. This cell is referred to as the primary cell (PCell). The PCell is a cell, operating on the primary frequency, in which the UE either performs the initial connection establishment procedure or initiates the connection re-establishment procedure. Depending on UE capabilities, secondary cells (SCells) can be configured to form together with the PCell a set of serving cells. An SCell is a cell providing additional radio resources on top of special cell (SpCell). The configured set of serving cells for a UE therefore always consists of one PCell and one or more SCells. For dual connectivity (DC) operation, the term SpCell refers to the PCell of the master cell group (MCG) or the primary SCell (PSCell) of the secondary cell group (SCG). An SpCell supports PUCCH transmission and contention-based random access, and is always activated. The MCG is a group of serving cells associated with a master node, comprised of the SpCell (PCell) and optionally one or more SCells. The SCG is the subset of serving cells associated with a secondary node, comprised of the PSCell and zero or more SCells, for a UE configured with DC. For a UE in RRC_CONNECTED not configured with CA / DC, there is only one serving cell comprised of the PCell. For a UE in RRC_CONNECTED configured with CA / DC, the term "serving cells" is used to denote the set of cells comprised of the SpCell(s) and all SCells. In DC, two MAC entities are configured in a UE: one for the MCG and one for the SCG.

[0103] FIG. 7 shows a data flow example in the 3GPP NR system to which implementations of the present disclosure is applied.

[0104] 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.

[0105] In the PHY layer, the uplink transport channels UL-SCH and random access channel (RACH) are mapped to their physical channels physical uplink shared channel (PUSCH) and physical random access channel (PRACH), respectively, and the downlink transport channels DL-SCH, BCH and PCH are mapped to physical downlink shared channel (PDSCH), physical broadcast channel (PBCH) and PDSCH, respectively. In the PHY layer, uplink control information (UCI) is mapped to physical uplink control channel (PUCCH), and downlink control information (DCI) is mapped to physical downlink control channel (PDCCH). A MAC PDU related to UL-SCH is transmitted by a UE via a PUSCH based on an UL grant, and a MAC PDU related to DL-SCH is transmitted by a BS via a PDSCH based on a DL assignment.

[0106] Hereinafter, contents regarding mobility are described.

[0107] The mobility may comprise PCell change, PSCell change (or, secondary node (SN) change), and / or PSCell addition (or, SN addition).

[0108] In the present disclosure, the term "handover (HO)" may mean PCell change, or may be a broad concept that includes not only PCell change but also PSCell change / addition.

[0109] In the present disclosure, the terms "handover" and "mobility" can be used interchangeably.

[0110] In the present disclosure, the description regarding handover can also be applied to other mobility procedures (e.g., PSCell change / addition).

[0111] There may be at least two types of mobility: network-controlled mobility (or, legacy mobility) and UE-based mobility (or, conditional mobility).

[0112] The network-controlled mobility (or, legacy mobility) is a mobility where the network determines a target cell for mobility, and configures UE with the target cell. The network may transmit, to the UE, anRRCReconfigurationmessage comprising a configuration for the target cell. The UE may execute a mobility to the target cell and / or apply the configuration for the target cell, upon receiving the cell configuration for the target cell.

[0113] The UE-based mobility (or, conditional mobility) is a mobility where the network configures the UE with a plurality of candidate cells, and the UE determines a target cell which satisfies a mobility execution condition among the plurality of candidate cells. The conditional mobility may comprise at least one of a conditional PCell change / conditional handover (CHO) or a conditional PSCell mobility. The conditional PSCell mobility may comprise conditional PSCell addition / change (CPAC), including conditional PSCell addition (CPA) and / or conditional PSCell change (CPC). The network may transmit, to the UE, anRRCReconfigurationmessage comprisingConditionalReconfigurationinformation element (IE), which comprises a list of conditional reconfigurations for the plurality of candidate cells. A conditional reconfiguration for a candidate cell may comprise an identifier of the conditional reconfiguration, a mobility execution condition for the candidate cell, and a configuration for the candidate cell (i.e., target cell configuration / candidate cell configuration). The UE may evaluate the mobility execution conditions for the plurality of candidate cells, and when a mobility execution condition for a candidate cell is satisfied, the UE may consider the candidate cell as a target cell, and execute a mobility to the target cell and / or apply the configuration for the target cell (i.e., target cell configuration / candidate cell configuration).

[0114] According to various embodiments, the mobility execution condition may be satisfied / met when an entry condition (or, entering condition) for the mobility execution condition is satisfied / met for at least a time-to-trigger (TTT) for the mobility execution condition. The entry condition / entering condition may mean that the mobility execution condition is initially met. Once the entry condition is met, the mobility execution condition will be considered to be met if the entry condition is met for time duration TTT continuously.

[0115] FIG. 8 shows an example flow of a recovery procedure according to an embodiment of the present disclosure.

[0116] Referring to FIG. 8, UE may detect SCG / MCG failure. For example, UE may detect / declare RLF separately for the MCG and for the SCG.

[0117] If radio link failure is detected for MCG, fast MCG link recovery is configured and the SCG is not deactivated, the UE triggers fast MCG link recovery. Otherwise, the UE initiates the RRC connection re-establishment procedure. During the execution of PSCell addition or PSCell change, if radio link failure is detected for MCG, the UE initiates the RRC connection re-establishment procedure.

[0118] During fast MCG link recovery, the UE suspends MCG transmissions for all radio bearers, except SRB0, and, if any, BH RLC channels and reports the failure withMCGFailureInformationmessage to the MN via the SCG, using the SCG leg of split SRB1 or SRB3.

[0119] The UE includes in theMCGFailureInformationmessage the measurement results available according to current measurement configuration of both the MN and the SN. Once the fast MCG link recovery is triggered, the UE maintains the current measurement configurations from both the MN and the SN, and continues measurements based on configuration from the MN and the SN, if possible. The UE initiates the RRC connection re-establishment procedure if it does not receive anRRCConnectionReconfigurationmessage,RRCReconfigurationmessage,MobilityFromNRCommandmessage,MobilityFromEUTRACommandmessage,RRCConnectionReleasemessage orRRCReleasemessage within a certain time after fast MCG link recovery was initiated.

[0120] Upon reception of theMCGFailureInformationmessage, the MN can sendRRCConnectionReconfigurationmessage,RRCReconfigurationmessage,MobilityFromNRCommandmessage,MobilityFromEUTRACommandmessage,RRCConnectionRelease message orRRCReleasemessage to the UE, using the SCG leg of split SRB1 or SRB3. Upon receiving anRRCConnectionReconfigurationmessage,RRCReconfigurationmessage,MobilityFromNRCommandmessage orMobilityFromEUTRACommandmessage, the UE resumes MCG transmissions for all radio bearers. For example, UE may receive theRRCConnectionReconfigurationmessage,RRCReconfigurationmessage,MobilityFromNRCommandmessage orMobilityFromEUTRACommandmessage may comprise a switch command for a target PCell comprising a configuration for the target PCell. The UE may switch to the target PCell based on the switch command by applying the configuration for the target PCell. Upon receiving anRRCConnectionReleasemessage orRRCReleasemessage, the UE releases all the radio bearers and configurations.

[0121] It is up to network implementation to guarantee that the RRC-related messages are delivered to the UE by the SN before the release of its control plane resources.

[0122] The following SCG failure cases are supported:

[0123] - SCG RLF;

[0124] - SCG beam failure while the SCG is deactivated;

[0125] - SN addition / change failure;

[0126] - For EN-DC, NGEN-DC and NR-DC, SCG configuration failure or CPC configuration failure (only for messages on SRB3);

[0127] - For EN-DC, NGEN-DC and NR-DC, SCG RRC integrity check failure (on SRB3);

[0128] - For EN-DC, NGEN-DC and NR-DC, consistent UL LBT failure on PSCell;

[0129] - For IAB-MT, reception of a BH RLF indication from SCG;

[0130] - CPA / CPC or subsequent CPAC execution failure;

[0131] - SCG LTM cell switch failure.

[0132] Upon SCG failure, if MCG transmissions of radio bearers are not suspended, the UE suspends SCG transmissions for all radio bearers and, if any, BH RLC channels, if the SCG failure is not triggered by SCG beam failure, and reports theSCGFailureInformationto the MN, instead of triggering re-establishment. If SCG failure is detected while MCG transmissions for all radio bearers are suspended, the UE initiates the RRC connection re-establishment procedure.

[0133] SCG / MCG failure handling by UE also applies to IAB MT.

[0134] In all SCG failure cases, the UE maintains the current measurement configurations from both the MN and the SN and the UE continues measurements based on configuration from the MN and the SN if possible. The SN measurements configured to be routed via the MN will continue to be reported after the SCG failure.

[0135] UE may not continue measurements based on configuration from the SN after SCG failure in certain cases (e.g., UE cannot maintain the timing of PSCell).

[0136] The UE includes in theSCGFailureInformationmessage the measurement results available according to current measurement configuration of both the MN and the SN. The MN handles theSCGFailureInformationmessage and may decide to keep, change, or release the SN / SCG. For example, after transmitting theSCGFailureInformationmessage, UE may receive a switch command for a target PSCell comprising a configuration for the target PSCell. The UE may switch to the target PSCell based on the switch command by applying the configuration for the target PSCell. In all the cases, the measurement results according to the SN configuration and the SCG failure type may be forwarded to the old SN and / or to the new SN.

[0137] In case of CPA / CPC, upon transmission of theSCGFailureInformationmessage to the MN, the UE stops evaluating the CPA / CPC execution condition. In case of subsequent CPAC, upon transmission of theSCGFailureInformationmessage to the MN or upon transmission of theMCGFailureInformationmessage to the SN, the UE stops evaluating the subsequent CPAC execution condition. The UE is not required to continue measurements for candidate PSCell(s) for execution condition upon transmission of theSCGFailureInformationmessage to the MN.

[0138] Upon / after initiating the connection re-establishment procedure, the UE may perform cell selection in accordance with the cell selection process. Upon / after selecting a suitable cell as a result of the cell selection in accordance with the cell selection process, the UE shall:

[0139] 1> ifattemptCondReconfigis configured; and

[0140] 1> if the selected cell is a candidate cell among the configured candidate cells for conditional mobility:

[0141] 2> perform the conditional mobility to the candidate cell based on applying candidate cell configuration / target cell configuration for the candidate cell (i.e., switch to the candidate cell by applying a configuration of the candidate cell);

[0142] 1> else:

[0143] 2> initiate transmission of theRRCReestablishmentRequestmessage.

[0144] The UE may transmit theRRCReestablishmentRequestmessage to the selected cell. When theRRCReestablishmentmessage is received from the selected cell in response to theRRCReestablishmentRequestmessage, the UE may consider that the connection re-establishment procedure succeeded, switch to the selected cell and / or transmit theRRCReestablishmentCompletemessage to the selected cell.

[0145] Meanwhile, in some area, UE may be prevented from transmitting a signal on a certain frequency resource according to national regulations and / or mobile operator's desire / requirement. For example, no-transmit-zone (NTZ) may be enforced for aerial UEs, where the UE is not allowed to transmit a signal on a frequency or a frequency range affected by the NTZ zone.

[0146] The NTZ may be a specific zone where UE should refrain from using a certain frequency resources, e.g., due to regulation requirements. For example, for a certain frequency region, a certain area may be defined as NTZ. UE may be required to stop transmitting a signal on the frequency region if the UE is in the NTZ area.

[0147] If UE enters the area (e.g., NTZ) and the current serving frequency cannot be used for transmission due to the regulation of the requirements in the area, the communication between the UE and the network may be lost. The UE cannot initiate mobility based on mobility / handover command because UE cannot confirm the reception of the mobility / handover command due to the transmission blocking.

[0148] While the UE remains in the concerned area (e.g., NTZ), the DL quality may be still good, and hence physical layer problem may not be detected. Since the UL transmission is completely blocked, UL transmission based RLF declaration may not be detected or may be detected with some delay. In the meantime, the UE may experience service interruption.

[0149] To avoid the interruption and / or communication deadlock in the special zone (e.g., NTZ), if UE enters the zone and the UE's serving frequency is affected by the zone, the UE may declare the failure of the serving cell and hence initiate a recovery procedure.

[0150] FIG. 9 shows an example of a method performed by a communication device for recovery procedure according to an embodiment of the present disclosure. The method may also be performed by UE and / or wireless device.

[0151] Referring to FIG. 9, in step S901, the communication device may receive information for a zone, and information for one or more frequencies related to the zone.

[0152] In step S903, the communication device may identify a current position of the communication device.

[0153] In step S905, based on i) the current position of the communication device belonging to the zone, and ii) a serving frequency for the communication device being included in the one or more frequencies related to the zone, the communication device may switch to a cell on a frequency other than the one or more frequencies related to the zone.

[0154] According to various embodiments, the communication device may detect a failure of a serving cell on the serving frequency, based on i) the current position of the communication device belonging to the zone, and ii) the serving frequency being included in the one or more frequencies related to the zone.

[0155] According to various embodiments, the communication device may initiate a connection re-establishment procedure for a recovery of the failure of the serving cell on the serving frequency. The communication device may select the cell on the frequency other than the one or more frequencies related to the zone during the connection re-establishment procedure.

[0156] According to various embodiments, the communication device may transmit a re-establishment request message via the selected cell. The communication device may receive a re-establishment message via the selected cell. The communication device may switch to the selected cell after receiving the re-establishment message.

[0157] According to various embodiments, the communication device may be configured with configurations of candidate cells for conditional mobility. Based on the cell being a candidate cell for conditional mobility, the communication device may switch to the candidate cell by applying a configuration of the candidate cell.

[0158] According to various embodiments, the serving cell may comprise primary cell (PCell) and the failure comprises a master cell group (MCG) radio link failure (RLF). The communication device may transmit MCG failure information message based on detecting the MCG failure. After transmitting the MCG failure information message, the communication device may receive a switch command for the cell on the frequency other than the one or more frequencies related to the zone. The communication device may switch to the cell based on the switch command.

[0159] According to various embodiments, the serving cell may comprise primary secondary cell (PSCell) and the failure comprises a secondary cell group (SCG) radio link failure (RLF). The communication device may transmit SCG failure information message based on detecting the SCG failure. After transmitting the SCG failure information message, the communication device may receive a switch command for the cell on the frequency other than the one or more frequencies related to the zone. The communication device may switch to the cell based on the switch command.

[0160] According to various embodiments, the communication device may transmit report information (e.g., RLF report) indicating the failure of the serving cell. The report information may comprise at least one of information for the serving cell or a failure cause set to a transmission blocking by the zone.

[0161] According to various embodiments, the failure of the serving cell may be detected while a physical layer problem is not detected on the serving cell, a random access transmission problem is not detected on the serving cell, and a maximum number of radio link control (RLC) retransmissions has not been reached.

[0162] According to various embodiments, a signal quality of the cell may be worse than that of one or more cells on the serving frequency.

[0163] According to various embodiments, based on i) the current position of the communication device belonging to the zone, and ii) the serving frequency being included in the one or more frequencies related to the zone, the communication device may search for a frequency other than the one or more frequencies related to the zone. Based on there being no frequency other than the one or more frequencies related to the zone, the communication device may enter a non-connected state (e.g., idle / inactive state). The communication device may suspend a communication. Based on the current position of the communication device leaving the zone, the communication device may resume the communication.

[0164] According to various embodiments, the zone may comprise a no-transmit zone (NTZ) where the communication device is not allowed to transmit a signal on the one or more frequencies related to the zone.

[0165] According to various embodiments, the communication device may receive a configuration including zone　information and frequency information associated with the　zone. The communication device may identify the current position. Based on the current position entering the zone and the current serving frequency being the frequency associated with the zone, the communication device may initiate a connection recovery procedure.

[0166] According to various embodiments, the communication device may declare a radio link failure based on the current position entering the zone and the current serving frequency being the frequency associated with the zone. While performing the connection recovery procedure, the communication device may deprioritize the frequency associated with the zone for cell selection / reselection / mobility. Based on identifying that any detected cell is on the frequency being the frequency associated with the zone, the communication device may leave RRC_CONNECTED. Based on leaving RRC_CONNECTED, the communication deivce may indicate to upper layers that communication is suspended. Based on the current position leaving the zone while the communication is suspended, the communication device may indicate to upper layers that communication can be resumed

[0167] FIG. 10 shows an example of a signal flow between a communication device and a network node for a recovery procedure according to an embodiment of the present disclosure. The network node may comprise a base station (BS).

[0168] Referring to FIG. 10, in step S1001, the network node may transmit, to a communication device, information for a zone, and information for one or more frequencies related to the zone.

[0169] In step S1003, the communication device may identify a current position of the communication device.

[0170] In step S1005, based on i) the current position of the communication device belonging to the zone, and ii) a serving frequency for the communication device being included in the one or more frequencies related to the zone, the communication device may switch to a cell on a frequency other than the one or more frequencies related to the zone.

[0171] Hereinafter, detailed implementations regarding triggering a connection recovery upon entering a special zone (e.g., NTZ) are described.

[0172] FIG. 11 show an example of a method for triggering a connection recovery upon entering a special zone according to an embodiment of the present disclosure.

[0173] Referring to FIG. 11, in step S1101, UE receive zone information and frequency information related to the corresponding zone(s).

[0174] The zone information may comprise information for one or more zones. Each zone may represent a 3-dimensional closure. Each zone may be represented by a collection of polygons, where each polygon represents a certain polygon in 3D coordinates. Each zone may be represented by a 3D coordinate (e.g., {latitude, longitude, altitude}) and radius.

[0175] The frequency information may comprise one or more frequencies affected by the corresponding zone(s). The association between zone information and frequency information may be configured such that for each zone, affected frequencies are configured or such that for each frequency, affected zones are configured.

[0176] In step S1103, UE may identify its current position and determine whether the current position is included in a zone indicated by the zone information.

[0177] In step S1105, if UE's current position is included in the zone and the UE identifies that the UE's special cell (SpCell) frequency (e.g., PCell frequency / serving frequency) is affected by the zone, the UE may initiate connection recovery procedure.

[0178] To initiate the recovery procedure, the UE may declare a radio link failure (RLF) that leads to initiation of RRC connection re-establishment or initiation of a fast recovery procedure indicating the failure of the SpCell (or failure of MCG / SCG) to network via other available cell or cell group.

[0179] For another example, to declare an RLF in the zone, the UE may consider that UE's lower layer experiences "out-of-sync" consecutively, which results in physical layer problem detection and starting an RLF related timer (e.g., T310). The RLF related timer (e.g., T310) may expire (or, RLF is detected) earlier by using a shorter timer value or zero value.

[0180] While performing the recovery procedure, the UE may de-prioritize the frequency of the previous SpCell / or and the UE may de-prioritize a frequency affected by the zone, based on the frequency information related to the zone.

[0181] In case of cell (re)selection during RRC re-establishment, UE may deprioritize the frequency affected by the zone and / or cells on the frequency affected by the zone.

[0182] In case of performing mobility to a (pre-)configured candidate cell for recovery, UE may deprioritize a candidate cell on the frequency affected by the zone.

[0183] In step S1107, the UE may switch to a cell on a frequency that is not affected by the zone.

[0184] In some implementations, if UE identifies that all detected cells are affected by the zone, UE may leave RRC_CONNECTED and enter RRC_IDLE / RRC_INACTIVE. Upon leaving RRC_CONNECTED, UE may indicate to upper layers that communication is suspended. If the UE detects that the current position of the UE leaves the zone while the communication is suspended, UE may indicate to upper layers that communication can be resumed.

[0185] FIG. 12 shows an example of declaration of RLF upon entering NTZ affecting the PCell according to an embodiment of the present disclosure. In FIG. 12, it is assumed that UE is configured with only a PCell.

[0186] Referring to FIG. 12, in step S1201, UE may UE receive zone information related to the NTZ and frequency information on frequencies affected by the NTZ.

[0187] In step S1203, UE may detect that the UE enters the NTZ and / or the current PCell frequency (i.e., serving frequency) is not allowed for transmission due to NTZ.

[0188] In step S1205, UE may declare a radio link failure upon detecting that the UE enters the NTZ and / or the current PCell frequency is not allowed for transmission due to NTZ.

[0189] In step S1207, the UE may initiate re-establishment as a result of declaring the RLF. The UE may initiate re-establishment even if physical layer problem has not been detected or random access transmission problem has not been detected, or RLC max retransmission has not been reached.

[0190] In step S1209, during re-establishment, UE does not select a cell on the previous PCell frequency (i.e., serving frequency) even if the cell's signal quality is very strong, but select a cell on other frequency (i.e., frequency other than the serving frequency) that is not affected by the NTZ. For example, the signal quality of the selected cell may be worse than that of one or more cells on the serving frequency.

[0191] In step S1211, UE may switch to the selected cell on the frequency that is not affected by the NTZ.

[0192] FIG. 13 shows an example of declaration of MCG RLF upon entering NTZ affecting the MCG according to an embodiment of the present disclosure. In FIG. 13, it is assumed that UE is configured with MCG and SCG.

[0193] Referring to FIG. 13, in step S1301, UE may receive zone information related to NTZ and frequency information on frequencies affected by the NTZ.

[0194] In step S1303, UE may detect that the UE enters the NTZ and / or the current PCell of MCG frequency (i.e., serving frequency) is affected by the NTZ.

[0195] In step S1305, UE declare a failure of MCG upon detecting that the UE enters the NTZ and / or the current PCell of MCG frequency is affected by the NTZ.

[0196] In step S1307, the UE may initiate a fast MCG recovery procedure upon declaring the failure of MCG.

[0197] In step S1309, during the fast MCG recovery procedure, the UE may transmit to Master Node via the SCG a message (i.e.,MCGFailureInformationmessage) indicating the failure of the MCG.

[0198] In step S1311, after transmitting theMCGFailureInformationmessage, the UE may receive a switch command for a new PCell on other frequency (i.e., frequency other than the serving frequency) that is not affected by the NTZ. The switch command may comprise a configuration for the new PCell.

[0199] In step S1313, the UE may switch to the new PCell on the frequency that is not affected by the NTZ based on the switch command (i.e., based on applying the configuration for the new PCell).

[0200] FIG. 14 shows an example of declaration of SCG RLF upon entering NTZ affecting the SCG according to an embodiment of the present disclosure. In FIG. 14, it is assumed that UE is configured with MCG and SCG.

[0201] Referring to FIG. 14, in step S1401, UE may receive zone information related to NTZ and frequency information on frequencies affected by the NTZ.

[0202] In step S1403, UE may detect that the UE enters the NTZ and / or the current SpCell of SCG frequency (i.e., serving frequency) is affected by the NTZ.

[0203] In step S1405, UE may declare a failure of SCG upon detecting that the UE enters the NTZ and / or the current SpCell of SCG frequency is affected by the NTZ.

[0204] In step S1407, UE may initiate a fast SCG recovery procedure upon declaring the failure of SCG.

[0205] In step S1409, during the fast SCG recovery procedure, UE may transmit to Secondary Node via the MCG a message (i.e.,SCGFailureInformationmessage) indicating the failure of the SCG.

[0206] In step S1411, after transmitting theSCGFailureInformationmessage, the UE may receive a switch command for a new PSCell on other frequency (i.e., frequency other than the serving frequency) that is not affected by the NTZ. The switch command may comprise a configuration for the new PSCell.

[0207] In step S1413, the UE may switch to the new PSCell on the frequency that is not affected by the NTZ based on the switch command (i.e., based on applying the configuration for the new PSCell).

[0208] FIG. 15 shows an example of declaration of serving cell failure upon entering NTZ affecting a SCell according to an embodiment of the present disclosure. In FIG. 15, it is assumed that UE is configured with multiple serving cells (e.g., PCell and SCell(s)).

[0209] Referring to FIG. 15, in step S1501, UE may receive zone information related to NTZ and frequency information on frequencies affected by the NTZ.

[0210] In step S1503, UE may detect that the UE enters the NTZ and / or one of the serving cell other than a special cell (PCell) is affected by the NTZ (i.e., SCell is affected).

[0211] In step S1505, UE may declare a failure of the serving cell upon detecting that the UE enters the NTZ and / or one of the serving cell other than a special cell is affected by the NTZ.

[0212] In step S1507, UE may transmit, to the network, an RLF report indicating the failure of the serving cell. UE may indicate to network the failure of the serving cell by sending a RRC message comprising the RLF report. The RRC message / RLF report may indicate the serving cell and / or a failure cause set to transmission blocking and / or communication blocking.

[0213] Furthermore, the method in perspective of the communication device described in the present disclosure (e.g., in FIG. 9) may be performed by the first wireless device 100 shown in FIG. 2 and / or the UE 100 shown in FIG. 3.

[0214] More specifically, the communication device comprises at least one transceiver comprising a first receiver and a second receiver, at least processor, and at least one computer memory operably connectable to the at least one processor and storing instructions that, based on being executed by the at least one processor, perform operations.

[0215] The operations comprise: receiving information for a zone, and information for one or more frequencies related to the zone; identifying a current position of the communication device; and based on i) the current position of the communication device belonging to the zone, and ii) a serving frequency for the communication device being included in the one or more frequencies related to the zone, switching to a cell on a frequency other than the one or more frequencies related to the zone.

[0216] Furthermore, the method in perspective of the communication device described in the present disclosure (e.g., in FIG. 9) may be performed by a software code 105 stored in the memory 104 included in the first wireless device 100 shown in FIG. 2.

[0217] More specifically, at least one computer readable medium (CRM) stores instructions that, based on being executed by at least one processor, perform operations comprising: receiving information for a zone, and information for one or more frequencies related to the zone; identifying a current position of the communication device; and based on i) the current position of the communication device belonging to the zone, and ii) a serving frequency for the communication device being included in the one or more frequencies related to the zone, switching to a cell on a frequency other than the one or more frequencies related to the zone.

[0218] Furthermore, the method in perspective of the communication device described in the present disclosure (e.g., in FIG. 9) may be performed by control of the processor 102 included in the first wireless device 100 shown in FIG. 2 and / or by control of the processor 102 included in the UE 100 shown in FIG. 3.

[0219] More specifically, an apparatus configured to / adapted to operate in a wireless communication system (e.g., communication device / UE) comprises at least processor, and at least one computer memory operably connectable to the at least one processor. The at least one processor is configured to / adapted to perform operations comprising: receiving information for a zone, and information for one or more frequencies related to the zone; identifying a current position of the communication device; and based on i) the current position of the communication device belonging to the zone, and ii) a serving frequency for the communication device being included in the one or more frequencies related to the zone, switching to a cell on a frequency other than the one or more frequencies related to the zone.

[0220] Furthermore, the method in perspective of a network node described in the present disclosure (e.g., in FIG. 10) may be performed by the second wireless device 200 shown in FIG. 2. The network node may be related to a serving cell.

[0221] More specifically, the network node comprises at least one transceiver, at least processor, and at least one computer memory operably connectable to the at least one processor and storing instructions that, based on being executed by the at least one processor, perform operations.

[0222] The operations comprise: transmitting, to a communication device, information for a zone, and information for one or more frequencies related to the zone, wherein the communication device is configured to perform operations comprising: identifying a current position of the communication device; and based on i) the current position of the communication device belonging to the zone, and ii) a serving frequency for the communication device being included in the one or more frequencies related to the zone, switching to a cell on a frequency other than the one or more frequencies related to the zone.

[0223] The present disclosure may have various advantageous effects.

[0224] For example, even if UE enters a zone and the UE's serving frequency is affected by the zone where the frequency cannot be used for communication, the UE may perform a recovery procedure so that long service interruption or communication deadlock in the zone can be avoided.

[0225] 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.

[0226] 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 performed by a communication device adapted to operate in a wireless communication system, the method comprising:receiving information for a zone, and information for one or more frequencies related to the zone;identifying a current position of the communication device; andbased on i) the current position of the communication device belonging to the zone, and ii) a serving frequency for the communication device being included in the one or more frequencies related to the zone, switching to a cell on a frequency other than the one or more frequencies related to the zone.2.The method of claim 1, further comprising:detecting a failure of a serving cell on the serving frequency, based on i) the current position of the communication device belonging to the zone, and ii) the serving frequency being included in the one or more frequencies related to the zone.3.The method of claim 2, further comprising:initiating a connection re-establishment procedure for a recovery of the failure of the serving cell on the serving frequency;selecting the cell on the frequency other than the one or more frequencies related to the zone during the connection re-establishment procedure.4.The method of claim 3, further comprising:transmitting a re-establishment request message via the selected cell;receiving a re-establishment message via the selected cell,wherein the switching comprises switching to the selected cell after receiving the re-establishment message.5.The method of claim 1 or 3, wherein the communication device is configured with configurations of candidate cells for conditional mobility, andwherein the switching comprises:based on the cell being a candidate cell for conditional mobility, switching to the candidate cell by applying a configuration of the candidate cell.6.The method of claim 2, wherein the serving cell comprises primary cell (PCell) and the failure comprises a master cell group (MCG) radio link failure (RLF),wherein the method further comprises:transmitting MCG failure information message based on detecting the MCG failure; andafter transmitting the MCG failure information message, receiving a switch command for the cell on the frequency other than the one or more frequencies related to the zone, andwherein the switching comprises switching to the cell based on the switch command.7.The method of claim 2, wherein the serving cell comprises primary secondary cell (PSCell) and the failure comprises a secondary cell group (SCG) radio link failure (RLF),wherein the method further comprises:transmitting SCG failure information message based on detecting the SCG failure; andafter transmitting the SCG failure information message, receiving a switch command for the cell on the frequency other than the one or more frequencies related to the zone, andwherein the switching comprises switching to the cell based on the switch command.8.The method of claim 2, further comprising transmitting report information indicating the failure of the serving cell,wherein the report information comprises at least one of information for the serving cell or a failure cause set to a transmission blocking by the zone.9.The method of claim 2, wherein the failure of the serving cell is detected while a physical layer problem is not detected on the serving cell, a random access transmission problem is not detected on the serving cell, and a maximum number of radio link control (RLC) retransmissions has not been reached.10.The method of claim 1, where a signal quality of the cell is worse than that of one or more cells on the serving frequency.11.The method of claim 1, further comprising:based on i) the current position of the communication device belonging to the zone, and ii) the serving frequency being included in the one or more frequencies related to the zone, searching for a frequency other than the one or more frequencies related to the zone;based on there being no frequency other than the one or more frequencies related to the zone, entering a non-connected state;suspending a communication; andbased on the current position of the communication device leaving the zone, resuming the communication.12.The method of claim 1, wherein the zone comprises a no-transmit zone (NTZ) where the communication device is not allowed to transmit a signal on the one or more frequencies related to the zone.13.The method of claims 1, wherein the communication device is in communication with at least one of a user equipment (UE), a mobile device, a network, or autonomous vehicles.14.A communication device configured to operate in a wireless communication system, the UE comprising:at least one transceiver comprising a first receiver and a second receiver;at least one processor; andat least one memory operatively coupled to the at least one processor and storing instructions that, based on being executed by the at least one processor, perform operations comprising:receiving information for a zone, and information for one or more frequencies related to the zone;identifying a current position of the communication device;based on i) the current position of the communication device belonging to the zone, and ii) a serving frequency for the communication device being included in the one or more frequencies related to the zone, switching to a cell on a frequency other than the one or more frequencies related to the zone.15.The communication device of claim 14, wherein the communication device is adapted to implement a method of one of claims 2 to 13.16.A network node configured to operate in a wireless communication system, the network node comprising:at least one transceiver;at least one processor; andat least one memory operatively coupled to the at least one processor and storing instructions that, based on being executed by the at least one processor, perform operations comprising:transmitting, to a communication device, information for a zone, and information for one or more frequencies related to the zone,wherein the communication device is configured to perform operations comprising:identifying a current position of the communication device; andbased on i) the current position of the communication device belonging to the zone, and ii) a serving frequency for the communication device being included in the one or more frequencies related to the zone, switching to a cell on a frequency other than the one or more frequencies related to the zone.17.A method performed by a network node configured to operate in a wireless communication system, the method comprising:transmitting, to a communication device, information for a zone, and information for one or more frequencies related to the zone,wherein the communication device is configured to perform operations comprising:identifying a current position of the communication device; andbased on i) the current position of the communication device belonging to the zone, and ii) a serving frequency for the communication device being included in the one or more frequencies related to the zone, switching to a cell on a frequency other than the one or more frequencies related to the zone.18.The method of claim 17, wherein the communication device is adapted to implement a method of one of claims 1 to 13.19.An apparatus adapted to operate in a wireless communication system, the apparatus comprising:at least processor; andat least one memory operatively coupled to the at least one processor and storing instructions that, based on being executed by the at least one processor, perform operations comprising:receiving information for a zone, and information for one or more frequencies related to the zone;identifying a current position of the communication device; andbased on i) the current position of the communication device belonging to the zone, and ii) a serving frequency for the communication device being included in the one or more frequencies related to the zone, switching to a cell on a frequency other than the one or more frequencies related to the zone.20.A non-transitory computer readable medium (CRM) having stored thereon a program code implementing instructions that, based on being executed by at least one processor, perform operations comprising:receiving information for a zone, and information for one or more frequencies related to the zone;identifying a current position of the communication device; andbased on i) the current position of the communication device belonging to the zone, and ii) a serving frequency for the communication device being included in the one or more frequencies related to the zone, switching to a cell on a frequency other than the one or more frequencies related to the zone.

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