Method and apparatus for controlling CQI reporting

Abstract

Various examples of the disclosure provide a method of a user equipment (UE) configured to perform contention-based Msg3 transmission, the method comprising: configuring the UE to report a channel quality indicator (CQI); determining to perform a contention-based Msg3 transmission; and determining whether to report CQI in Msg3 based on performing the contention-based Msg3 transmission. According to various examples of the disclosure, a network entity transmits, to a UE, information configuring the UE to report a CQI in Msg3, and receives, from the UE, Msg3 including a CQI in a contention-based Msg3 transmission.

Description

METHOD AND APPARATUS FOR CONTROLLING CQI REPORTING

[0001] Certain examples of the present disclosure relate to methods, apparatus and / or systems for performing RACH-less data transmission, sending contention-based Msg3, and / or controlling CQI reporting. In various examples, a CQI measurement or report is not sent by a UE in contention-based Msg3. In further examples, the UE is configured to measure CQI on Msg2, and, when sending contention-based Msg3, not report any CQI. In an example, the UE is an eMTC UE or a NB-IoT UE. In various examples, a UE is configured to measure CQI on another signal, i.e. other than Msg2, and report the measured CQI when sending contention-based Msg3. In some examples, this other signal is system information; while in some examples, this other signal is PDCCH used for paging. Various examples provide conditions for reporting CQI in a contention-based Msg3, such as carrier- and / or narrowband- related conditions. Various examples provide a method for reporting CQI in Msg5.

[0002] 5G mobile communication technologies define broad frequency bands such that high transmission rates and new services are possible, and can be implemented not only in "Sub 6GHz" bands such as 3.5GHz, but also in "Above 6GHz" bands referred to as mmWave including 28GHz and 39GHz. In addition, it has been considered to implement 6G mobile communication technologies (referred to as Beyond 5G systems) in terahertz bands (for example, 95GHz to 3THz bands) in order to accomplish transmission rates fifty times faster than 5G mobile communication technologies and ultra-low latencies one-tenth of 5G mobile communication technologies.

[0003] At the beginning of the development of 5G mobile communication technologies, in order to support services and to satisfy performance requirements in connection with enhanced Mobile BroadBand (eMBB), Ultra Reliable Low Latency Communications (URLLC), and massive Machine-Type Communications (mMTC), there has been ongoing standardization regarding beamforming and massive MIMO for mitigating radio-wave path loss and increasing radio-wave transmission distances in mmWave, supporting numerologies (for example, operating multiple subcarrier spacings) for efficiently utilizing mmWave resources and dynamic operation of slot formats, initial access technologies for supporting multi-beam transmission and broadbands, definition and operation of BandWidth Part (BWP), new channel coding methods such as a Low Density Parity Check (LDPC) code for large amount of data transmission and a polar code for highly reliable transmission of control information, L2 pre-processing, and network slicing for providing a dedicated network specialized to a specific service.

[0004] Currently, there are ongoing discussions regarding improvement and performance enhancement of initial 5G mobile communication technologies in view of services to be supported by 5G mobile communication technologies, and there has been physical layer standardization regarding technologies such as Vehicle-to-everything (V2X) for aiding driving determination by autonomous vehicles based on information regarding positions and states of vehicles transmitted by the vehicles and for enhancing user convenience, New Radio Unlicensed (NR-U) aimed at system operations conforming to various regulation-related requirements in unlicensed bands, NR UE Power Saving, Non-Terrestrial Network (NTN) which is UE-satellite direct communication for providing coverage in an area in which communication with terrestrial networks is unavailable, and positioning.

[0005] Moreover, there has been ongoing standardization in air interface architecture / protocol regarding technologies such as Industrial Internet of Things (IIoT) for supporting new services through interworking and convergence with other industries, Integrated Access and Backhaul (IAB) for providing a node for network service area expansion by supporting a wireless backhaul link and an access link in an integrated manner, mobility enhancement including conditional handover and Dual Active Protocol Stack (DAPS) handover, and two-step random access for simplifying random access procedure (2-step RACH for NR). There also has been ongoing standardization in system architecture / service regarding a 5G baseline architecture (for example, service based architecture or service based interface) for combining Network Functions Virtualization (NFV) and Software-Defined Networking (SDN) technologies, and Mobile Edge Computing (MEC) for receiving services based on UE positions.

[0006] As 5G mobile communication systems are commercialized, connected devices that have been exponentially increasing will be connected to communication networks, and it is accordingly expected that enhanced functions and performances of 5G mobile communication systems and integrated operations of connected devices will be necessary. To this end, new research is scheduled in connection with eXtended Reality (XR) for efficiently supporting Augmented Reality (AR), Virtual Reality (VR), Mixed Reality (MR) and the like, 5G performance improvement and complexity reduction by utilizing Artificial Intelligence (AI) and Machine Learning (ML), AI service support, metaverse service support, and drone communication.

[0007] Furthermore, such development of 5G mobile communication systems will serve as a basis for developing not only new waveforms for providing coverage in terahertz bands of 6G mobile communication technologies, multi-antenna transmission technologies such as Full Dimensional MIMO (FD-MIMO), array antennas and large-scale antennas, metamaterial-based lenses and antennas for improving coverage of terahertz band signals, high-dimensional space multiplexing technology using Orbital Angular Momentum (OAM), and Reconfigurable Intelligent Surface (RIS), but also full-duplex technology for increasing frequency efficiency of 6G mobile communication technologies and improving system networks, AI-based communication technology for implementing system optimization by utilizing satellites and Artificial Intelligence (AI) from the design stage and internalizing end-to-end AI support functions, and next-generation distributed computing technology for implementing services at levels of complexity exceeding the limit of UE operation capability by utilizing ultra-high-performance communication and computing resources.

[0008] It is an aim of certain examples of the present disclosure to address, solve and / or mitigate, at least partly, at least one of the problems and / or disadvantages associated with the related art, for example at least one of the problems and / or disadvantages described herein. It is an aim of certain examples of the present disclosure to provide at least one advantage over the related art, for example at least one of the advantages described herein.

[0009] According to an aspect of the disclosure, there is provided a method of a user equipment (UE) configured to perform contention-based Msg3 transmission, the method comprising: configuring the UE to report a CQI; determining to perform a contention-based Msg3 transmission; and determining whether to report CQI in Msg3 based on performing the contention-based Msg3 transmission. According to another aspect, a method of a UE configured to perform contention-based Msg3 transmission comprises: configuring CQI reporting; determining to perform a contention-based Msg3 transmission; and determining whether to report CQI in Msg3 based on performing the contention-based Msg3 transmission.

[0010] According to various examples, the contention-based Msg3 transmission is performed without performing a RACH procedure, and / or without the UE previously transmitting Msg1 (e.g. as part of a procedure also involving the transmission of Msg3), and / or without the UE previously receiving Msg2 (e.g. as part of a procedure also involving transmission of Msg3).

[0011] According to various examples, the UE determines to report the CQI in Msg3; and the method comprises transmitting the Msg3 including the CQI.

[0012] According to various examples, the method comprises generating a downlink channel quality report (DCQR) and access stratum (AS) release assistance information (RAI) medium access control (MAC) control element (CE) for reporting the CQI in Msg3.

[0013] According to various examples, the UE is configured to report the CQI in Msg3 by upper layers.

[0014] According to various examples, it is determined to perform the contention-based Msg3 transmission in response to a trigger.

[0015] According to various examples, determining whether to report CQI in Msg3 is based on a carrier associated with performing the contention-based Msg3 transmission.

[0016] According to various examples, determining whether to report CQI in Msg3 comprises: if the carrier associated with performing the contention-based Msg3transmission is different to a carrier associated with the CQI measurement, determining not to report the CQI in Msg3.

[0017] According to various examples, wherein the carrier associated with performing contention-based Msg3 transmission is a carrier on which the Msg3 is transmitted.

[0018] According to various examples, determining whether to report CQI in Msg3 comprises: if the carrier associated with performing the contention-based Msg3transmission is the same as a carrier associated with the CQI measurement, determining to report the CQI in Msg3.

[0019] According to various examples, the method further comprises setting cqi-NPDCCH field of the Msg3 to include latest results of downlink channel quality measurements for reporting the CQI in Msg3.

[0020] According to various examples, the Msg3 includes RRCEarlyDataRequest.

[0021] According to various examples, the UE is a narrowband- (NB-) internet of things (IoT) UE or an enhanced machine-type communication (eMTC) UE.

[0022] According to various examples, the UE supports reporting CQI in Msg3.

[0023] According to various examples, the method further comprises receiving, from a network entity, information configuring CQI reporting at the UE.

[0024] According to various examples, the information is included in system information received from the network entity.

[0025] According to various examples, the information is included in a mpdcch-CQI-Reporting field in SIB2 for an eMTC UE or in a cqi-Reporting field in SIB2-NB for a NB-IoT UE.

[0026] According to various examples, the UE is configured to measure CQI based on the information.

[0027] According to another aspect of the disclosure, there is provided a UE configured to perform contention-based Msg3 transmission; wherein the UE is configured to report a channel quality indicator (CQI); and wherein the UE is configured to: determine to perform a contention-based Msg3 transmission, and determine whether to report CQI in Msg3 based on performing the contention-based Msg3 transmission.

[0028] According to various examples, the UE is configured to perform a method according to any one or more of the examples relating to a method of a UE given above.

[0029] According to another aspect of the disclosure, there is provided a method of a network entity, the method comprising: transmitting, to a user equipment (UE), information configuring the UE to report a channel quality indicator (CQI) in Msg3; and receiving, from the UE, Msg3 including a CQI in a contention-based Msg3 transmission.

[0030] According to various examples, the Msg3 includes a downlink channel quality report (DCQR) and access stratum (AS) release assistance information (RAI) medium access control (MAC) control element (CE) for reporting the CQI in Msg3.

[0031] According to various examples, the information configuring the UE to transmit the CQI in Msg3 is included in system information.

[0032] According to various examples, the information configuring the UE to transmit the CQI in Msg3 is included in a mpdcch-CQI-Reporting field in SIB2 when the UE is an enhanced machine-type communication (eMTC) UE or in a cqi-Reporting field in SIB2-NB when the UE is a narrowband- (NB-) internet of things (IoT) UE.

[0033] According to another aspect of the disclosure, there is provided a network entity configured to: transmit, to a user equipment (UE), information configuring the UE to report a channel quality indicator (CQI) in Msg3; and receive, from the UE, Msg3 including a CQI in a contention-based Msg3 transmission.

[0034] According to various examples, the network entity is configured to perform a method according to any one or more of the examples relating to a method of a network entity given above.

[0035] According to another aspect of the disclosure, there is provided a computer-readable storage medium comprising instructions which, when executed by at least one processor of an electronic device, cause the electronic device to perform a method according to any one of the aspects and / or examples given above.

[0036] Other aspects, advantages, and salient features of the disclosure will become apparent to those skilled in the art from the following detailed description taken in conjunction with the accompanying drawings.

[0037] Embodiments / examples of the present disclosure are further described hereinafter with reference to the accompanying drawings, in which:

[0038] Figure 1 shows a schematic representation of an example of a NTN.

[0039] Figure 2 shows examples of ephemeris synchronization operations where a) SIB31 functions normally and b) where RLF is triggered.

[0040] Figure 3 is a call flow diagram showing a random access procedure according to various examples.

[0041] Figure 4 is a call flow diagram showing an EDT procedure according to various examples.

[0042] Figure 5 is a call flow diagram showing a PUR procedure according to various examples.

[0043] Figure 6 is a call flow diagram showing reporting CQI in Msg3 of the random access procedure according to various examples.

[0044] Figure 7 is a call flow diagram showing a method for sending contention-based Msg3 according to various examples of the present disclosure.

[0045] Figures 8A and 8B are a call flow diagrams each showing a method for sending contention-based Msg3 according to various examples of the present disclosure.

[0046] Figure 9 is a flow diagram illustrating a method of controlling reporting of CQI in a contention-based Msg3 according to various examples of the present disclosure.

[0047] Figure 10 is a call flow diagram illustrating a method of sending a CQI report according to various examples of the present disclosure.

[0048] Figure 11 is a block diagram illustrating an example structure of a network entity according to various examples of the present disclosure.

[0049] Figure 12 is a flow diagram illustrating a method of a UE according to various examples of the present disclosure.

[0050] Figure 13 is a flow diagram illustrating a method of a network entity according to various examples of the present disclosure.

[0051] The following description of examples of the present disclosure, with reference to the accompanying drawings, is provided to assist in a comprehensive understanding of certain examples of the present disclosure. The description includes various specific details to assist in that understanding but these are to be regarded as merely exemplary. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the examples described herein can be made without departing from the scope of the invention or disclosure.

[0052] The same or similar components may be designated by the same or similar reference numerals, although they may be illustrated in different drawings.

[0053] Detailed descriptions of techniques, structures, constructions, functions or processes known in the art may be omitted for clarity and conciseness, and to avoid obscuring the subject matter of the present disclosure.

[0054] The terms and words used herein are not limited to the bibliographical or standard meanings, but are merely used to enable a clear and consistent understanding of the disclosure.

[0055] Throughout the description of this specification, the words "comprise", "include" and "contain" and variations of the words, for example "comprising" and "comprises", means "including but not limited to", and is not intended to (and does not) exclude other features, elements, components, integers, steps, processes, operations, functions, characteristics, properties and / or groups thereof.

[0056] Throughout the description of this specification, the singular form, for example "a", "an" and "the", encompasses the plural unless the context otherwise requires. For example, reference to "an object" includes reference to one or more of such objects.

[0057] Throughout the description, the expression "at least one of A, B and / or C" (or the like), the expression "and / or", and the expression "one or more of A, B and / or C" (or the like) should be seen to separately include all possible combinations, for example: A, B, C, A and B, A and C, A and B and C.

[0058] Throughout the description of this specification, language in the general form of "X for Y" (where Y is some action, process, operation, function, activity or step and X is some means for carrying out that action, process, operation, function, activity or step) encompasses means X adapted, configured or arranged specifically, but not necessarily exclusively, to do Y.

[0059] Features, elements, components, integers, steps, processes, operations, functions, characteristics, properties and / or groups thereof described or disclosed in conjunction with a particular aspect, embodiment or example are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith.

[0060] Certain examples of the present disclosure relate to methods, apparatus and / or systems for performing RACH-less data transmission, sending contention-based Msg3, and / or controlling CQI reporting. In various examples, a CQI measurement or report is not sent by a UE in contention-based Msg3. In further examples, the UE is configured to measure CQI on Msg2, and, when sending contention-based Msg3, not report any CQI. In an example, the UE is a eMTC UE or a NB-IoT UE. In various examples, a UE is configured to measure CQI on another signal, i.e. other than Msg2, and report the measured CQI when sending contention-based Msg3. In some examples, this other signal is system information; while in some examples, this other signal is PDCCH used for paging. Various examples provide conditions for reporting CQI in a contention-based Msg3, such as carrier- and / or narrowband- related conditions. Various examples provide a method for reporting CQI in Msg5.

[0061] The following examples are applicable to, and use terminology associated with, 3GPP 5G. However, the skilled person will appreciate that the techniques disclosed herein are not limited to these examples or to 3GPP 5G, and may be applied in any suitable system or standard, for example one or more existing and / or future generation wireless communication systems or standards. The skilled person will appreciate that the techniques disclosed herein may be applied in any existing or future releases of 3GPP 5G NR or any other relevant standard. For example, the functionality of the various network entities and other features disclosed herein may be applied to corresponding or equivalent entities or features in other communication systems or standards. Corresponding or equivalent entities or features may be regarded as entities or features that perform the same or similar role, function, operation or purpose within the network. In particular, the following disclosure should be considered at least in relation to 6G also, which is expected to use at least part of the 5G architecture, or equivalent, and to which the present disclosure also relates.

[0062] A particular network entity may be implemented as a network element on a dedicated hardware, as a software instance running on a dedicated hardware, and / or as a virtualised function instantiated on an appropriate platform, e.g. on a cloud infrastructure.

[0063] The skilled person will appreciate that the present disclosure is not limited to the specific examples disclosed herein. For example:

[0064] -　The techniques disclosed herein are not limited to 3GPP LTE, LTE-A, 5G, B5G or 6G.

[0065] -　One or more entities in the examples disclosed herein may be replaced with one or more alternative entities performing equivalent or corresponding functions, processes or operations.

[0066] -　One or more of the messages in the examples disclosed herein may be replaced with one or more alternative messages, signals or other type of information carriers that communicate equivalent or corresponding information.

[0067] -　One or more further elements, entities and / or messages may be added to the examples disclosed herein.

[0068] -　One or more non-essential elements, entities and / or messages may be omitted in certain examples.

[0069] -　The functions, processes or operations of a particular entity in one example may be divided between two or more separate entities in an alternative example.

[0070] -　The functions, processes or operations of two or more separate entities in one example may be performed by a single entity in an alternative example.

[0071] -　Information carried by a particular message in one example may be carried by two or more separate messages in an alternative example.

[0072] -　Information carried by two or more separate messages in one example may be carried by a single message in an alternative example.

[0073] -　The order in which operations are performed may be modified, if possible, in alternative examples.

[0074] -　The transmission of information between network entities is not limited to the specific form, type and / or order of messages described in relation to the examples disclosed herein.

[0075] Certain examples of the present disclosure may be provided in the form of an apparatus / device / network entity configured to perform one or more defined network functions and / or a method therefor. Such an apparatus / device / network entity may comprise one or more elements, for example one or more of receivers, transmitters, transceivers, processors, controllers, modules, units, and the like, each element configured to perform one or more corresponding processes, operations and / or method steps for implementing the techniques described herein. For example, an operation / function of X may be performed by a module configured to perform X (or an X-module). Certain examples of the present disclosure may be provided in the form of a system (e.g., a network) comprising one or more such apparatuses / devices / network entities, and / or a method therefor.

[0076] It will be appreciated that examples of the present disclosure may be realized in the form of hardware, software or a combination of hardware and software. Certain examples of the present disclosure may provide a computer program comprising instructions or code which, when executed, implement a method, system and / or apparatus in accordance with any aspect, example and / or embodiment disclosed herein. Certain embodiments of the present disclosure provide a machine-readable storage storing such a program.

[0077] A network according to one or more of the examples disclosed herein may include one or more of a Network Data Analytics Function (NWDAF) entity, an Access and Mobility Management Function (AMF) entity, a Session Management Function (SMF) entity, a Network Slice Selection Function (NSSF) entity, a Network Repository Function (NRF) entity, Application Function (AF) entity, and an Operation and Maintenance (OAM) entity. The network may include one or more Service Consumers (including one or more of the entities mentioned above and / or one or more other entities) that receive analytics from NWDAF. The skilled person will appreciate that a network may omit one or more of the entities mentioned above and / or may comprise one or more additional entities

[0078] As described above, the UE may perform the Msg3 transmission without having performed Msg1 and receiving Msg2. In that case, there needs to be methods to handle how to deal with any CQI reports in Msg3, as the UE will not receive a Msg2. That is, a problem may arise in that the UE has not received Msg2 yet may be configured to include CQI in Msg3 transmission. Various examples of the present disclosure aim to solve, address or mitigate issues(s) relating to such.

[0079] An aspect of the present disclosure relates to, or includes, methods for reporting, or determining / choosing how to report, CQI when the UE performs contention-based Msg. It is to be understood that all examples, aspects, embodiments, teachings etc. disclosed herein may also apply for NR NTN, LTE-M / eMTC NTN, E-UTRA NTN, and 6G NTN - i.e. the present disclosure is not limited to the specific cases used in the illustrative examples described herein.

[0080] Here, the term "Contention-based Msg3" is used, at times, to 1) indicate a procedure where data along with control plane signaling can be transmitted in a contention-based manner without having to perform random access, or 2) indicate any procedure where random access is performed but Msg1 and Msg2 is skipped. This may also be called, or the methods may also apply for, any of "contention-based PUR", "EDT without msg1", "RACH-less EDT", "RACH-less data transmission" or similar. Contention-based Msg3 may be termed "Msg3 without random access". This can be a generalization of RACH-less (E)DT where any procedure which normally uses the random access procedure may perform the random access procedure but only transmit Msg3.

[0081] Here, the term "Contention-based Msg3 transmission" may be used, which may be taken to mean transmitting the first message of a Contention-based Msg3 procedure as disclosed herein. Due to similarities to the random access procedures, this message may also be referred to as "Msg3", since it is an access procedure without the random access procedure, i.e. without Msg1 and Msg2.

[0082] Herein, any mention of physical downlink control channel (PDCCH) may refer to any type of PDCCH such as normal LTE PDCCH, NR PDCCH, EPDCCH, Machine-type PDCCH (MPDCCH) or NB-IoT PDCCH (NPDCCH).

[0083] While the term CQI and CQI reporting is used below, another term that may be used can be Downlink channel quality or Downlink channel quality reporting. The CQI or Downlink Channel Quality may provide the serving eNB with information about the minimum PDCCH repetition level or the minimum PDCCH aggregation level to satisfy a hypothetical PDCCH block error rate of 1%. Thus what is reported is the PDCCH repetition level and / or PDCCH aggregation level given block error rate of 1%.

[0084]

[0085] The content of the following documents is referred to below and / or their content provides background information that the following disclosure should be considered in the context of:

[0086] [1]　3GPP RP-202689 - MediaTek Inc., "New Study WID on NB-IoT / eTMC support for NTN"; 3GPP TSG RAN Meeting #90; Electronic Meeting, December 7 - 11, 2020.

[0087] [2]　3GPP RP-211557 - Thales, "Solutions for NR to support non-terrestrial networks (NTN)"; 3GPP TSG RAN meeting #91-e; e-meeting, March 22 - 26th, 2021.

[0088] [3]　3GPP RP-220953 - Thales, "NR NTN (Non-Terrestrial Networks) enhancements"; 3GPP TSG RAN Meeting #95e; Electronic Meeting, March 17 - 23, 2022.

[0089] [4]　3GPP RP-223519 - MediaTek Inc., "Revised WID on IoT NTN enhancements"; 3GPP TSG RAN Meeting #98e; Electronic, 12-16 December 2022.

[0090] [5]　3GPP RP-234077 - Deutsche Telekom (moderator, RAN VC), "New WID: Non-Terrestrial Networks (NTN) for Internet of Things (IoT) Phase 3"; 3GPP TSG RAN Meeting #102 ; Edinburgh, Scotland, December 11-15, 2023.

[0091] [6]　3GPP TS 38.331 -5G; NR; Radio Resource Control (RRC); Protocol specification, Release 18 (e.g., V18.1.0).

[0092] [7]　3GPP TS 36.331 - Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification, Release 18 (e.g. V18.1.0).

[0093]

[0094] Note: indicated version numbers are provided for illustrative purposes, other (including future) versions of these documents are considered also.

[0095]

[0096] Wireless or mobile (cellular) communications networks in which a mobile terminal (e.g., user equipment (UE), such as a mobile handset) communicates via a radio link with a network of base stations, or other wireless access points or nodes, have undergone rapid development through a number of generations. The 3rdGeneration Partnership Project (3GPP) design, specify and standardise technologies for mobile wireless communication networks. Fourth Generation (4G) and Fifth Generation (5G) systems (5GS) are now widely deployed, while beyond 5G (B5G) and 6G systems are being considered.

[0097] 3GPP standards for 4G systems include an Evolved Packet Core (EPC) and an Enhanced-UTRAN (E-UTRAN: an Enhanced Universal Terrestrial Radio Access Network). The E-UTRAN uses Long Term Evolution (LTE) radio technology. LTE is commonly used to refer to the whole system including both the EPC and the E-UTRAN, and LTE is used in this sense in the remainder of this document. LTE should also be taken to include LTE enhancements such as LTE Advanced and LTE Pro, which offer enhanced data rates compared to LTE.

[0098] In 5G systems a new air interface has been developed, which may be referred to as 5G New Radio (5G NR) or simply NR. NR is designed to support the wide variety of services and use case scenarios envisaged for 5G networks, though builds upon established LTE technologies B5G systems, such as 6G, are currently being considered and developed, and are expected to at least partly build on 5G systems.

[0099] New frameworks and architectures are being developed as part of 5G network (and beyond, such as 6G networks) in order to increase the range of functionality and use cases available through 5G networks.

[0100] IoT (Internet of Things) NTN (Non-Terrestrial Network) was a 3GPP study and work item in 3GPP release 17 to provide Non-Terrestrial Network access for E-UTRAN IoT devices (NB-IoT (Narrowband-IoT) and LTE-M / eMTC (Long-Term Evolution Machine Type Communication / enhanced machine-type communication)) (RP-202689 [1]].

[0101] An example of a NTN is shown in Figure 1. The NTN is shown to comprise NTN cell 110 and a NTN entity 180 associated with (e.g. controlling or configuring) NTN cell 110. The NTN entity 180 is connected to a gateway 120 via feeder link 170. The gateway 120 is connected to eNB / gNB 130, which communicates with core network 140. It will be appreciated that gateway and eNB / gNB 130 may be co-located or implemented together. A UE 150 is located with NTN cell 110. The UE 150 is connected to NTN entity 180 via access link 160. Accordingly, the UE 150 is connected to core network 140 via the NTN entity 180.

[0102] NR NTN was a work item in Rel-17 to specify adaptation to allow NR to function over NTN (RP-211557 [2]). Non-Terrestrial Network access may be through Lower Earth Orbit (LEO), Medium Earth Orbit (MEO) and Geostationary Orbit (GEO), as well as through High-Altitude Platform Systems (HAPS).

[0103] Following the Work items in Release 17 there were work items to enhance NR NTN (RP-220953 [3]) and IoT NTN (RP-223519 [4]) in Release 18.

[0104] The work item description for IoT NTN Rel-19 is the following (RP-234077 [5]):

[0105]

[0106] Narrowband Internet of Things and LTE-M

[0107] Narrowband Internet of Things (NB-IoT) is a 3GPP-defined network based on 4G E-UTRAN that supports ultra-low complexity devices with very narrow bandwidth that was introduced in 3GPP Release 13. It supports the massive Machine Type Communication (mMTC) 5G use case for IMT-2020. The use case of NB-IoT is to serve massive IoT application, where requirements for instance are to support enhanced coverage, power-efficient operation and a massive number of devices. Some of the features introduced are:

[0108] -　Support for enhanced coverage through low bandwidth and extreme amounts of repetitions.

[0109] -　Power efficient operation by allowing the UE to sleep for very long times, relaxed requirements and more efficient signal to establish with a cell.

[0110] LTE-M (or eMTC) is another technology that serves the mMTC 5G use case. Compared to NB-IoT, an LTE-M device is more like a simplified 4G E-UTRAN device with certain simplifications allowing for easier and cheaper implementation. It addressed a slight wider use case compared to NB-IoT, with higher data rates and is not quite as power efficient as NB-IoT. This type of device may also be referred to as a Cat M1 / 2 device or as Bandwidth Limited (BL) UE and UE in enhanced coverage.

[0111] Both LTE-M and NB-IoT are specified with what is known as User plane and Control plane enhancements for reduced signaling. In user plane solution, the UE supports AS security and Data radio bearers. In control plane, the UE does not support AS security and instead relies on NAS for security, which means that all data is routed through MME. Control plane is mandatory for NB-IoT and optional for LTE-M.

[0112] NTN System Information

[0113] As NTN has a number of NTN-specific information elements that are only required when accessing an NTN cell, and also due to the rather large information elements it was agreed that new system information blocks (SIB) was needed.

[0114] In NR NTN, SIB19 contains the required information to access an NTN cell. Referring to TS 38.331 [6], the following is disclosed in relation to SIB19:

[0115] (Start of excerpt from 38.331 V18.1.0 [6] )

[0116]

[0117]

[0118]

[0119]

[0120] (End of excerpt from 38.331 V18.1.0 [6] )

[0121] In IoT NTN, SIB31 contains the required information to access an IoT NTN cell. Referring to TS 38.331 [6], the following is disclosed in relation to SIB31:

[0122] (Start of excerpt from 36.331 V18.1.0 [7] )

[0123]

[0124]

[0125] (End of excerpt from 36.331 V18.1.0 [7] )

[0126] The system information contains the following:

[0127] -　Serving cell Ephemeris elements - which allows UE to calculate the satellite position for doppler and time pre-compensation. This can be of two formats:

[0128] - PVT format - which describes a (X,Y,Z) position as well as a speed vector (vX, vY, vZ).

[0129] - Orbital parameters - this describes the orbital movements of the satellite which is then used to infer the satellite position.

[0130] -　TA common parameters - this provides the common timing advance parameters which is introduced to compensate for the feeder link delays. The signaling consists of (in total taking up 57 bits)

[0131] - Absolute TA common, taking up 23 bits.

[0132] - Drift of the TA common - how the TA common drifts, i.e. the first derivative, taking up 19 bits.

[0133] - Variation of the TA common - how the TA common varies, i.e. the second derivative of the TA common, taking up 15 bits.

[0134] -　Synchronization validity duration - used to define how long the ephemeris and TA common is valid.

[0135] -　Epoch time - when the synchronization validity duration should start.

[0136] -　K-Offset - scheduling offset for timing relationship in NTN.

[0137] -　K-Mac - Scheduling offset used when the downlink and uplink frame timing is not aligned.

[0138] -　NR NTN specific information also include (as part of TS 38.331 [6]):

[0139] - T-Service (signaled in SIB3 in IoT NTN).

[0140] - Reference location and distance threshold - used for location-based measurement initiation in RRC IDLE and RRC Connected mode.

[0141] - Neighbour cell ephemeris

[0142] - This is used for idle mode measurements.

[0143] NTN System Information acquisition

[0144] As the ephemeris constantly changes due to the movement of the NTN payload, there is a need to make sure that the UE is correctly synchronized. Thus whenever a UE is connected to an eNB, the UE needs to read the system information. There is furthermore a timer (T317) associated with the ephemeris element that is started every time SIB31 is read. At expiry of T317, the UE is no longer considered synchronized and it will have to re-acquire SIB31 in order to stay synchronized. In NR NTN, the UE shall ensure that it has a recent ephemeris (SIB19 in NR) by reading the SIB in time by UE implementation. In IoT NTN, since an IoT UE (LTE-M and NB-IoT UE) is not expected to be able to acquire system information in connected mode, the UE tunes away and is likely unreachable while reading SIB31. If the IoT NTN UE is unable to read the SIB31 within a timer (T318) with a configured duration, the UE performs RLF (radio link failure) similar to other cases where RLF is performed. This operation can be seen in Figure 2.

[0145] Figure 2 illustrates receipt of SIB31 and timers T317 and T318 according to an example. That is, Figure 2 illustrates an ephemeris synchronization operation, where in a) SIB31 functions as normal and b) where UE fails to read SIB31 during T318 which then expires and triggers RLF.

[0146] In Figure 2 a), SIB31 is received (e.g. by a UE) at a time corresponding to 210. Upon or following expiration of timer T317, timer T318 starts. At a time corresponding to 215, SIB31 is received, before expiration of timer T318.

[0147] In Figure 2 b), SIB31 is received (e.g. by a UE) at a time corresponding to 220. Upon or following expiration of timer T317, timer T318 starts. At a time corresponding to 225, timer T318 has expired without SIB31 having been received. RLF is therefore triggered.

[0148] The T317 timer is different compared to a normal timer in RRC (radio resource control) as it is not started at having received the SIB31. This is because the ephemeris has an epoch time, which is the reference point in time of when the ephemeris is defined. Thus the T317 is started from the epoch time, which may be in the past or in the future relative to have received SIB31. This means that in a UE implementation, the timer may be started with a different value with what was signaled according to what was signaled in the field ul-SyncValidityDuration in SIB31.

[0149] Initial / random access procedure in IoT NTN

[0150] An example of an initial access procedure can be seen in Figure 3.

[0151] Briefly, the steps of Figure 3 may be considered as follows:

[0152] -　S310 - UE in RRC idle.

[0153] -　S320 - 0. GNSS measurement, acquire SIB31 and self pre-compensate.

[0154] -　S330 - 1. Msg1 / preamble.

[0155] -　S340 - 2. Msg2 / RAR.

[0156] -　S350 - Scheduling Msg3.

[0157] -　S360 - 3. Msg3 (PUSCH).

[0158] -　S370 - 4. Msg4 / Contention Resolution (PDSCH).

[0159] -　S380 - 5. Msg5 (PUSCH)

[0160] In more detail, the steps of Figure 3 may be described as follows:

[0161] In operation S310, the UE is in RRC idle mode.

[0162] In operation S320, the UE determines the timing advance (TA) pre-compensation using the UE position and the satellite position. The UE position is via GNSS, but other methods that do not rely on the network may also potentially be used, such as using inertial navigation system or similar. The satellite position is acquired via SIB19 and the UE also pre-compensates using TA-Common, which is the common timing advance from the satellite to the ground gate way where the base station resides.

[0163] In operation S330, the UE uses the pre-compensation and sends Msg1 which is the RACH (random access channel) preamble. The RACH preamble will represent a number between 1 and 64. The number selected by the is random, but there exists several rules to determine the range of preambles, depending on configurations and conditions - sometimes referred to as preamble division.

[0164] In operation S340, if the network (e.g. eNB, CN etc.) is able to detect and the determine the RACH preamble, the eNB responds with Msg2 or RAR (random access response).

[0165] In operations S350 and S360 (note, these may be combined into a single operation of scheduling and sending Msg3), the UE sends Msg3, which is sent using PUSCH (physical uplink shared channel). This message contains the first RRC message. The RRC message depends on the specific reason why the random access procedure was triggered. For example: for initial access it will be RRCSetupRequest; for resuming it is RRCConnectionResumeRequest; for re-establishing RRC it is RRCConnectionReestablishmentRequest; for CP-EDT it is RRCEarlyDataRequest etc.

[0166] In operation S370, since it is possible that two UEs select the same RAPID (random access preamble ID), there is a chance of collision. So in Msg4, sent over PDSCH in operation S370, this contention may be resolved using the Contention Resolution MAC CE. Msg4 also contains an RRC message that is a response to Msg3. This can for instance be RRCConnectionSetup, RRCConnectionResume, RRCConnectionReestablishment, RRCReject, RRCEarlyDataComplete etc.

[0167] In operation S380, the UE sends Msg5. Msg5 is a further message that is scheduled uplink message which would consist of the reply to the downlink RRC message in Msg4. Msg5 is sometimes not considered a part of the random access procedure, but a part of any access procedures. The RRC message carried in Msg5 may be RRCConnectionSetupComplete, RRCConnectionResumeComplete, RRCConnectionReestablishmentComplete and so on.

[0168] Early Data Transmission (EDT)

[0169] EDT (early data transmission) is a feature that allows a UE to start to transmit data already in Msg3. This is mostly for power-saving purposes where in the best case the UE would be able to transmit all of its data and then be released already in Msg4. In RRC Resume, the UE may not start transmitting data until after RRCResumeComplete in Msg5.

[0170] An example of the EDT procedure can be seen in Figure 4, from the perspective of PHY layer, MAC and RRC.

[0171] Briefly, the steps of Figure 4 may be considered as follows:

[0172] -　S410 - UE in RRC idle

[0173] -　S420 - 0. GNSS measurement, acquire SIB31 and self pre-compensate.

[0174] -　S430 - 1. Msg1 / preamble.

[0175] -　S440 - 2. Msg2 / RAR.

[0176] -　S450 - Scheduling Msg3.

[0177] -　S460 - 3. Msg3 (PUSCH)

[0178] RRCEarlyData - CP /

[0179] RRCResumeRequest + Data - UP.

[0180] -　S470 - 4. Msg4 / Contention Resolution (PDSCH)

[0181] RRCearlyDataComplete - CP /

[0182] RRCConnectionRelease - UP.

[0183] In more detail, the steps may be described as follows:

[0184] Operation S410 - UE is in RRC idle mode.

[0185] Operation S420 - same as in any random access procedure (e.g. see operation S320 of Figure 3).

[0186] Operation S430 - same as in any random access procedure (e.g. see operation S330 of Figure 3), but the UE selects a RACH preamble from a specific set of preambles that indicates that the UE will perform EDT.

[0187] In operation S440, if the network is able to detect and the determine the RACH preamble, the eNB responds with Msg2 or RAR.

[0188] In operations S450 and S460 (note, these may be combined into a single operation of scheduling and sending Msg3) UE sends Msg3. Msg3 may include user data transmissions. In User plane EDT, the Msg3 consists of the RRC message RRCConnectionResumeRequest along with data from a Data Radio Bearer (DRB). In Control plane EDT, the Msg3 consist of the RRC message RRCEarlyDataRequest which in turn contains a field for sending NAS messages which may contain data.

[0189] Since it is possible that two UEs select the same RAPID, there is a chance of collision. In operation S470, the Msg4 is sent by the network. That is, through Msg4, sent over PDSCH, this contention may be resolved using the Contention Resolution MAC CE. Msg4 may also contain an RRC message that is a response to Msg3. This can for instance be RRCSetup, RRCConnectionResume, RRCConnectionReestablishment, RRCReject, RRCEarlyDataComplete etc.

[0190] Preconfigured Uplink Resources (PUR)

[0191] PUR (preconfigured uplink resources) is a feature that allows for pre-configuring uplink transmissions without the need for random access. It also means that data can be transmitted without the UE needing to move to RRC connected, saving time and power consumption.

[0192] The PUR procedure can be seen in Figure 5, from the perspective of PHY layer, MAC and RRC.

[0193] Briefly, the steps of Figure 5 may be considered as follow:

[0194] -　S510 - 1. PURConfigurationRequest.

[0195] -　S520 - 2. RRCConnectionRelease (pur-Config).

[0196] -　S530 - 3. UE suspends RRC connection and goes to RRC idle.

[0197] -　S540 - 4. Data arrives in UL buffer.

[0198] -　S550 - 5. GNSS measurement, acquire SIB31 and self pre-compensate.

[0199] -　S560 - 6. PUR (PUSCH)

[0200] -　S570 - 7. Response.

[0201] In more detail, the steps of Figure 5 may be described as follows:

[0202] In operation S510, a UE may optionally send a request to request the UE to be configured with PUR. This request contains the requested number of PUR occasions, the periodicity and offset as well as the Transport Block Size (TBS), i.e. the size of the allocation for PUR.

[0203] In operation S520, if the network determines that the UE shall go to RRC idle and that it would be beneficial for the UE to be configured with PUR, then the network releases the UE and configures pur-Config (e.g. a PUR configuration) in the RRCConnectionRelease message.

[0204] The PUR configuration contains the parameters that gives the PUR resource, such as periodicity and offset, the startSFN, the start subframe, the number of PUR occasions, the PUR-RNTI, the pur-TimeAlignmentTimer, and RSRP threshold, a response window timer, the configurations for MPDCCH, PDSCH, PUCCH and PUSCH and the PDSCH frequency hopping.

[0205] In operation S530, the UE suspends the RRC connection and moves to RRC idle.

[0206] In operation S540, traffic arrives in the uplink buffer.

[0207] In operation S550, in an NTN the UE would at least have to self-precompensate the timing advance. The UE may potentially also have to acquire the GNSS position as well as acquire SIB31 to ensure that it has the most updated satellite ephemeris.

[0208] In operation S560, the UE uses the configured PUR-resources and performs uplink transmission using PUSCH:

[0209] a. In control plane (CP) solution the PUR message consist of the RRC message RRCEarlyDataRequest, which contains the transparent NAS container which may contain data or NAS signalling.

[0210] b. In user plane (UP) solution the PUR message consists of the RRCConnectionResumeRequest as well as uplink data from any of the radio bearers that triggered the PUR.

[0211] In operation S570, the network responds to the PUR:

[0212] a. In CP solution the response may include 1) a Layer 1 acknowledgement, 2) a Timing Advance MAC CE command that updates the TA or 3) an RRCEarlyDataComplete. If none of these are received, the UE considers the procedure to not be completed.

[0213] b. In UP solution the response either include the RRCConnectionRelease message which successfully completes the PUR transmission. The response may also (i.e. optionally) include downlink data transmissions.

[0214] In 3GPP Release 19 IoT NTN there is the following objective (from RP-234077 [5]):

[0215]

[0216] In both eMTC and NB-IoT, enhancements have been introduced whereby a UE can be configured to report CQI (channel quality indicator, sometimes known as Downlink Channel Quality) in a Msg3 of the random access procedure. In this case, the UE will be configured in advance via system information (e.g.: mpdcch-CQI-Reporting in SIB2 for eMTC, and cqi-Reporting in SIB2-NB for NB-IoT) to measure the CQI on the PDCCH of Msg2, and then report it in Msg3. An example of this can be seen in Figure 6.

[0217] Briefly, the steps of Figure 6 may be considered as follows:

[0218] -　S610 - UE in RRC idle

[0219] -　S620 - 1. Msg1 / preamble.

[0220] -　S630 - 2. Msg2 / RAR.

[0221] -　S640 - Measure CQI (or downlink channel quality).

[0222] -　S460 - 3. Msg3 (PUSCH) including CQI (or downlink channel quality).

[0223] -　S470 - 4. Msg4 / Contention Resolution (PDSCH).

[0224] As mentioned, the UE measures CQI (or downlink channel quality) on the PDCCH of Msg2 (i.e. based on Msg2), and reports the measurement in Msg3.

[0225] However, in the IoT NTN objective of 'Support of Capacity enhancements for uplink', the UE may perform the Msg3 transmission without having performed Msg1 and receiving Msg2. In that case, there needs to be methods to handle how to deal with any CQI reports in Msg3, as the UE will not receive a Msg2.

[0226]

[0227] 1.　CQI Reporting in a Contention-based Msg3

[0228] The present disclosure provides various examples, embodiments etc. to handle CQI reporting in Msg3 if a UE performed contention-based Msg3. It will be appreciated that any two or more of these examples / embodiments may be combined.

[0229]

[0230] eMTC-related aspects

[0231] According to various embodiments of the present disclosure, for an eMTC UE that has been configured to report CQI in Msg3, e.g. via mpdcch-CQI-Reporting, the UE may be configured (e.g. via / by receiving configuration information from a cell, base station, network or other entity) to not report any CQI if the UE is performing contention-based Msg3. In other words, a UE may be configured to omit CQI reporting if performing contention-based Msg3, or to perform contention-based Msg3 without reporting CQI. In some examples, this may also mean that a UE performing RACH-based Msg3, i.e. first sending Msg1 and Msg2, will be configured to report CQI if it performs RACH-based Msg3.

[0232] For example, since the CQI reported in Msg3 can be done via the downlink channel quality report (DCQR) and access stratum (AS) release assistance information (RAI) medium access control (MAC) control element (CE) (DCQR and AS RAI MAC CE), this can be done either by not reporting the CQI or by reporting the information field but not setting it. If the UE is configured to not report the DCQR and AS RAI MAC CE, then this may be under condition that the network has configured mpdcch-CQI-Reporting and that the UE performs contention-based Msg3. The condition to report the DCQR and AS RAI MAC CE may also be that the UE performs RACH-based access, for instance RACH-based EDT.

[0233] One issue is that the DCQR and AS RAI MAC CE report two unrelated fields. It may still be beneficial that a UE reports the fields in AS RAI MAC CE. In this case the UE may still be configured to report the AS RAI fields when performing contention-based Msg3 transmissions. Thus, in various examples the UE may still report any type of AS RAI indication. This may be done by reusing fields in a MAC header, e.g. the F2 and R field. Additionally or alternatively, this may also be done by including a new MAC CE, or alternatively that the UE includes any type of AS RAI indication in an RRC message, such as RRCResumeRequest, RRCEarlyDataRequest or similar. Any type of AS RAI indication may for instance include the values 'No RAI information', 'No subsequent DL and UL data transmission is expected' or 'A single subsequent DL transmissions is expected'.

[0234] In various examples, if the UE still reports the CQI but does not set the fields, then the UE may either report the CQI via the DCQR and AS RAI MAC CE or reusing fields in a MAC header (F2 and R field).

[0235] In various examples, if the UE is configured to report the DCQR and AS RAI MAC CE, but not report the CQI, then the UE may still set the AS RAI parts, but may, for example, set the DCQR to any value, or a set value such as noMeasurements. This can be advantageous, as the AS RAI part of the DCQR and AS RAI MAC CE may be valuable for the network. Not setting the AS RAI fields may impact the access procedures. In other words, in various examples, the condition for sending the DCQR and AS RAI MAC CE but not reporting the CQI parts may be that: (i) the network has configured CQI reporting, e.g. via mpdcch-CQI-Reporting, (ii) the UE is capable of CQI reporting in Msg3, and (iii) the UE is performing contention-based Msg3. For instance, this may mean that the UE sets the value of the CQI Quality report to no measurement or the like (e.g. a predetermined value or indicator). A specification example can be seen in Specification Example #1 below. This may mean that the configuration of CQI reporting for contention-based Msg3 may be considered to only configure AS RAI reporting in Msg3. An example may be found in Figure 7.

[0236] Briefly, the steps of Figure 7 may be considered to read as follows:

[0237] -　S710 - UE in RRC idle.

[0238] -　S720 - 1. Configure the UE to measure CQI on Msg2 PDDCH.

[0239] -　S730 - 2. UE determines to perform contention-based Msg3 (without Msg1 / Msg2).

[0240] -　S740 - 3. Contention-based Msg3 including DCQR and AS RAI MAC CE, where CQI report is not set.

[0241] -　S750 - 4. Network ignores CQI report in DCQR and AS RAI MAC CE.

[0242] Operation 750 is optional, particularly from the UE perspective.

[0243] The network may be configured to ignore any CQI reporting associated in a contention-based Msg3.

[0244] In various examples, for contention-based Msg3 transmissions, the UE may be configured to report the DCQR and AS RAI MAC CE if a contention-based Msg3 transmission is being initiated or triggered. An example of this can be seen in specification example #2 below. This is different from reporting a CQI measurement in a RACH-based Msg3, where the trigger for including the DCQR and AS RAI MAC CE in the Msg3 is normally that the UE receives an uplink grant on the PDCCH for the MAC entity's RA-RNTI (random access (RA)- Radio Network Temporary Identifier (RNTI)).

[0245]

[0246] NB-IoT-related aspects

[0247] According to various embodiments of the present disclosure, CQI (this may also be called DL channel quality) reporting for contention-based Msg3 is not considered supported. In other words, if the network configures CQI reporting, or cqi-Reporting, then for contention-based Msg3 the UE will not report the CQI in a message for contention based Msg3. For example, if the UE is configured to perform Contention-based Msg3 or EDT (early data transmission), the UE supports reporting CQI in Msg3 and the network has configured CQI reporting (e.g. cqi-Reporting), then the UE may not report the CQI measurement. The UE may also be considered to (e.g. configured to, or determines / chooses to) disregard the CQI configuration. In some examples, the UE considers (or determines, chooses etc.) or is configured to report (or only report) CQI measurement in Msg3 if the UE is not performing contention-based Msg3. An example of this is shown in specification example #3 below. In various examples, this also means that the UE reports the CQI if the UE performs RACH-based Msg3.

[0248] In various examples, the UE sets the cqi-NPDCCH field to no measurements if a UE performs Contention-based Msg3 and the network has configured CQI reporting.

[0249]

[0250] Common to NB-IoT and eMTC aspects

[0251] In various embodiments of the present disclosure, a separate configuration to specifically configure CQI reporting for contention-based Msg3 is provided to configure whether a UE shall report CQI in a Msg3. This may be configured in broadcasted system information. For example, it may be considered that the UE receives system information (e.g. broadcast in a cell) which configures CQI reporting for contention-based Msg3 (e.g. how to handle CQI reporting for contention-based Msg3, such as according to one of the methods above or not to report CQI measurement), or that the UE receives configuration information, e.g. in broadcast system information, which configures CQI reporting for contention-based Msg3.

[0252] In order to be able to report the CQI, CQI may need to be measured on a different signal other than the PDCCH transmission in Msg2, for instance on a different PDCCH. Various embodiments of the present disclosure relate to methods for such CQI measuring.

[0253] According to various embodiments of the present disclosure, the UE uses the CQI measured at any PDCCH before performing the contention-based Msg3. This may include measuring the CQI of a PDCCH used to schedule system information. Here, the UE may measure the CQI from a PDCCH that schedules system information, and saves / stores the value. When the UE later performs contention-based Msg3, the UE may report the saved / stored CQI value. The saved or stored CQI value may be any one or more of a last saved or stored CQI value, any measured CQI value, an average of the CQI values (e.g. measured or stored CQI values), the maximum CQI value (e.g. among measured or stored CQI values) or the minimum CQI value (e.g. among measured or stored CQI values). As a UE, in general, always needs to acquire system information, this method of measuring CQI may be a suitable replacement to measuring CQI based on Msg2, i.e. may be a suitable solution as to how to measure CQI when a UE is configured to perform contention-based Msg3. In an example, in the case of acquiring SystemInformationBlockType31, which is crucial for NTN, the UE may need to acquire the SIB just before accessing the cell - this ensures that the measure CQI is recent enough. An example of this is illustrated in Figure 8A. An example of this is also shown in specification example #4 below. In some examples, this (e.g. using the CQI measured at any PDCCH before performing the contention-based Msg3, such as CQI measured based on or from a PDCCH that schedules system information) may be configured in system information, e.g. in a SIB1 message or in a SIB2 message. One advantage of configuring it in a SIB1 message is that SIB1 is not scheduled by PDCCH, whereas SIB2 is.

[0254] Briefly, the steps of Figure 8A may be considered to read as follows:

[0255] -　S810 - UE in RRC idle.

[0256] -　S820 - 1. Configure the UE to measure CQI on PDCCH used to schedule system information.

[0257] -　S830 - Network sends PDCCH.

[0258] -　S840 - 2. UE measures CQI from PDCCH used to schedule system information.

[0259] -　S850 - 3. Contention-based Msg3 {include CQI measured on PDCCH}.

[0260]

[0261] According to various embodiments of the present disclosure, for reporting CQI in Msg3, the UE measures the PDCCH that is used for paging. This may be done for reporting CQI in the case of Mobile Terminated (MT) access, i.e. when contention-based Msg3 is transmitted for mobile terminated access. In an example, the UE is configured, when in idle mode, by a network to measure CQI of PDCCH used for paging. In a second step, when the UE monitors paging, the UE measures and saves / stores the CQI. In a third step, if the paging message is intended for the UE, the UE initiates MT access via contention-based Msg3 and then the UE reports the CQI of the PDCCH used for paging. An example of this is illustrated in Figure 8B. An example of this is also shown in specification example #4 below.

[0262] Briefly, the steps of Figure 8B may be considered to read as follows:

[0263] -　S850 - UE in RRC idle.

[0264] -　S860 - 1. Configure the UE to measure CQI on PDCCH used for paging.

[0265] -　S870 - Paging.

[0266] -　S880 - 2. UE measures CQI from PDCCH used for paging.

[0267] -　S890 - 3. Contention-based Msg3 {include CQI measured on PDCCH}.

[0268]

[0269] In various examples, using PDCCH from Paging and / or system information scheduling may be configured in a separate configuration. In various examples, using PDCCH from Paging and / or system information scheduling may be considered configured if the network has configured CQI reporting and the UE supports contention-based Msg3. It may also (i.e. additionally or alternatively) be configured in a RRC Connection Release message when the UE is released to RRC idle by the network. It may also (i.e. additionally or alternatively) be configured in a Paging message or be considered configured in a Paging message when mt-EDT is included.

[0270] According to various embodiments of the present disclosure, the CQI is derived (e.g. measured, obtained, determined etc.) from RSRP measurements used to estimate the UE coverage level.

[0271] There may be a restriction that the CQI measurement on the PDCCH needs to be performed on the same carrier or narrowband as that which the UE is performing access on or that which the UE is performing the contention-based Msg3 attempt on. Accordingly, in circumstances where the carrier or narrowband is different, then the CQI may not be considered valid. For example, if the PDCCH scheduling system information is received on one carrier but the access attempt is performed on another carrier or narrowband, then the CQI measurement may not be considered valid and thus not reported. An example of this is illustrated in Figure 9. The method of Figure 9 may be performed by a UE.

[0272] In operation S910 of Figure 9, the UE is configured (e.g. by the network) to acquire CQI on a downlink signal, and the UE acquires CQI. More generally, operation S910 may be considered to describe an operation of the UE acquiring CQI on a downlink signal.

[0273] In operation S920, the UE determines a carrier to perform random access on.

[0274] In operation S930, it is determined whether the selected carrier is the same as the carrier on which the CQI measurement is performed on.

[0275] If so (YES path), in operation S940 the UE reports CQI in a contention-based Msg3.

[0276] If not (NO path), in operation S950 the UE does not report CQI in a contention-based Msg3.

[0277] More generally, operations S930-S950 may be considered to describe: based on a selected carrier (to perform RA on) being the same as the carrier on which CQI measurement was performed on, report CQI in a contention-based Msg3. In another, more-general example, operations S930-S950 may be considered to describe: based on a selected carrier (to perform RA on) being different to as the carrier on which CQI measurement was performed on, do not report CQI in a contention-based Msg3. In other words, whether or not to report CQI in a contention-based Msg3 may be based on the carrier on which the CQI measurement was performed and a carrier on which RA is to be performed.

[0278] In various examples, it is also the case that if the CQI is derived from RSRP measurements used to estimate the UE coverage level, and contention-based Msg3 is performed on a different carrier or narrowband other than where the RSRP measurement was performed, the UE may not include the measurement. In which case, the UE may set the reported value to noMeasurements.

[0279] In various examples, the UE may also (i.e. additionally or alternatively) be configured to report a CQI measurement performed on another carrier or narrowband regardless.

[0280] If the UE is configured to perform CQI measurement on any PDCCH or any other signal from the network, the UE may indicate in a message what signal that the UE used to perform the CQI measurement. For example, if the DCQR and AS RAI MAC CE is used, then certain reserved fields of the MAC CE may be used to indicate which signal was used. In an example, '00' may mean that PDCCH for system information was used, '01' may mean that PDCCH for paging was used, '10' may mean that a broadcasted reference signal is used and / or '11' means that a measurement for determining the UE coverage level was used. It will be appreciated that these examples are non-limiting, and that all combinations of these example meanings for '00', '01', '10' and / or '11' are included herein.

[0281] In various examples, the UE may also (i.e. additionally or alternatively) use a CQI measurement performed and stored previously (i.e. a stored CQI measurement). This may be advantageous if the UE performs random access where it was previously connected to an eNB. For instance, if a UE performs RRC re-establishment, or performs random access in a cell where it is already connected, the UE can be configured to use this CQI measurement (e.g. the CQI measurement from the performed random access) to report in a Msg3.

[0282] According to various embodiments of the present disclosure, the CQI is not reported in a Msg3 (e.g. contention-based Msg3), but rather reported in a -Complete message, e.g. a Msg5 message. In this case, the CQI may be measured on (or based on) Msg4, which may be the PDCCH of Msg4. Msg4 may be received by the UE after sending contention-based Msg3. After having measured the CQI on Msg4, it is then reported in a message that follows or subsequent message, e.g. a Msg5. In various examples, this is reported in a MAC CE, which may be the DCQR and AS RAI MAC CE or any other MAC CE. It may also (i.e. additionally or alternatively) be reported in a -Complete message; for example in RRCResumeComplete or RRCConnectionSetupComplete. An example of this is shown in Figure 10. In various examples, this behaviour (i.e. the UE reporting CQI in a -Complete message, such as Msg5, instead of in Msg3) is configured in system information. In some examples, this behaviour is considered to be configured if the network configures cqi-Reporting (for NB-IoT) or mpdcch-CQI-Reporting (for eMTC), or there may be a separate configuration. In other words, in various examples, where a UE is configured by the network to report CQI, the UE reports measured (or stored) CQI in a -Complete message such as Msg5

[0283] Briefly, the steps of Figure 10 may be considered to read as follows:

[0284] -　S1010 - UE in RRC idle.

[0285] -　S1020 - 1. Msg3 (PUSCH) - RRCConnectionResumeRequest - Data.

[0286] -　S1030 - 2. Msg4 / Contention Resolution - RRCConnectionResume.

[0287] -　S1040 - 3. Msg5 - RRCConnectionResumeComplete + CQI report.

[0288]

[0289] As mentioned, the CQI reported in S1040 may be measured based on Msg4 received in S1030, e.g. the PDCCH of Msg4. Operation S1020 may be the sending of a contention-based Msg3, e.g. as described above in relation to other examples.

[0290] In various examples, the UE also (i.e. additionally or alternatively) reports the CQI in a Msg5, but the CQI is measured from the PDCCH which schedules the Msg5 PUSCH (i.e. as opposed to being based on Msg4).

[0291] In various embodiments of the present disclosure, a UE, which may be a 5G or 6G UE, reports measurements of an SSB in a contention-based Msg3. This may be configured specifically for SSB (synchronization signal block) measurements. For example, the network configures the UE to report SSB quality or signal strength in a first initial access message. In this case, RSRP may be reported. In an example, the UE is configured (e.g. via configuration information received from the network, a cell, a base station etc.) to perform a measurement on SSB and report the result in an initial access message (e.g. first initial access message).

[0292]

[0293] There are now provided several examples of changes to standards specification (in this case, TS 36.321 or TS 36.331) to implement various features disclosed herein. The text shownunderlinedindicates a change, e.g. addition, to the existing version of the specification.

[0294]

[0295] Example #1

[0296]

[0297] Example #2

[0298]

[0299] Example #3

[0300]

[0301] Example #4

[0302]

[0303] Figure 11 is a block diagram of an exemplary apparatus, or network entity, that may be used in examples of the present disclosure. The skilled person will appreciate said entity may be implemented, for example, as a network element on a dedicated hardware, as a software instance running on a dedicated hardware, and / or as a virtualised function instantiated on an appropriate platform, e.g. on a cloud infrastructure.

[0304] The entity 1100 comprises a processor (or controller) 1101, a transmitter 1103 and a receiver 1105. The receiver 1105 is configured for receiving one or more messages from one or more other network entities, for example as described above. The transmitter 1103 is configured for transmitting one or more messages to one or more other network entities, for example as described above. The processor 1101 is configured for performing one or more operations, for example according to the operations as described above. It will be appreciated that an entity as described herein may be a virtual or logical entity, which may be implemented using or in an apparatus which comprises a processor, an antenna, a receiver and / or a transmitter etc. but which does not itself have a physical form (i.e. would not be said to comprise a processor, an antenna, a receiver and / or a transmitter etc.).

[0305] Figure 12 illustrates a method of a UE according to an embodiment of the present disclosure.

[0306] In step S1210, the UE is configured for CQI reporting. For example, step 1210 may describe configuring the UE to report a CQI.

[0307] In step 1220, the UE determines to perform a contention-based Msg3 transmission.

[0308] In step 1230, the UE determines whether to report CQI in Msg3 based on performing the contention-based Msg3 transmission.

[0309] Figure 13 illustrates a method of a network entity according to an embodiment of the present disclosure.

[0310] In step 1310, the network entity transmits, to a UE, information configuring the UE to report a CQI in Msg3. For example, receiving the information may cause the UE to configure itself to report a CQI in Msg3 based on the information.

[0311] In step 1320, the network receives, from the UE, Msg3 including a CQI in a contention-based Msg3 transmission.

[0312] It will be appreciated that, in each example / embodiment / aspect etc. described above, one or more features or operations may be omitted, modified or moved (e.g., to change the order of the features or the operations), if desired and appropriate. For example, referring to the method shown by the call flow diagram of any of the figures, it will be understood that one or more of the operations of these methods may be omitted, such as one or more operations which do not describe an aspect of the disclosure such as conditions for performing data transmission without RACH, selecting resources for data transmission without RACH, falling back from performing data transmission without RACH, or performing data transmission without RACH. Further, it will be appreciated that various examples may relate solely to conditions for performing data transmission without RACH, selecting resources for data transmission without RACH, falling back from performing data transmission without RACH, or performing data transmission without RACH - i.e. in some aspects of the present disclosure it is not necessary to recite all of these operations in combination. Additionally, one or more features or operations from any example / embodiment may be combined with features or operations from any other example / embodiment. In particular, regardless of whether or not a pointer towards a combination of features / examples is found herein, the present disclosure should be considered to include all combinations of two or more of the embodiments, examples etc. disclosed herein, and all combinations of two or more of the features disclosed herein.

[0313] The techniques described herein may be implemented using any suitably configured apparatus and / or system. Such an apparatus and / or system may be configured to perform a method according to any aspect, embodiment or example disclosed herein. Such an apparatus may comprise one or more elements, for example one or more of receivers, transmitters, transceivers, processors, controllers, modules, units, and the like, each element configured to perform one or more corresponding processes, operations and / or method steps for implementing the techniques described herein. For example, an operation / function of X may be performed by a module configured to perform X (or an X-module). The one or more elements may be implemented in the form of hardware, software, or any combination of hardware and software.

[0314] It will be appreciated that examples of the present disclosure may be implemented in the form of hardware, software or any combination of hardware and software. Any such software may be stored in the form of volatile or non-volatile storage, for example a storage device like a ROM, whether erasable or rewritable or not, or in the form of memory such as, for example, RAM, memory chips, device or integrated circuits or on an optically or magnetically readable medium such as, for example, a CD, DVD, magnetic disk or magnetic tape or the like.

[0315] It will be appreciated that the storage devices and storage media are embodiments of machine-readable storage that are suitable for storing a program or programs comprising instructions that, when executed, implement certain examples of the present disclosure. Accordingly, certain examples provide a program comprising code for implementing a method, apparatus or system according to any example, embodiment and / or aspect disclosed herein, and / or a machine-readable storage storing such a program. Still further, such programs may be conveyed electronically via any medium, for example a communication signal carried over a wired or wireless connection.

[0316] While the present disclosure has been shown, illustrated and described with reference to certain examples, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the scope of the disclosure.

[0317] The reader's attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

[0318] Various examples of the disclosure are in accordance with the following numbered paragraphs:

[0319] Paragraph 1.　A method of a user equipment configured to perform random access channel (RACH)-less data transmission, the method comprising: configuring the UE to measure channel quality indicator (CQI) on a signal received from an entity; determining whether to perform a RACH-less data transmission procedure; and controlling reporting of CQI based on the result of the determination.

[0320] Paragraph 2.　The method of Paragraph 1, wherein controlling reporting of CQI based on the result of the determination comprises: not reporting the CQI when it is determined to perform the RACH-less data transmission procedure, and / or not measuring the CQI when it is determined to perform the RACH-less data transmission procedure.

[0321] Paragraph 3.　The method of Paragraph 1 or Paragraph 2, further comprising: if it is determined to perform the RACH-less data transmission procedure, performing RACH-less data transmission without reporting CQI.

[0322] Paragraph 4.　The method of Paragraph 3, wherein the RACH-less data transmission includes information fields relating to CQI where the information fields are not set or are set to a preconfigured value (e.g. zero).

[0323] Paragraph 5.　The method of Paragraph 3 or Paragraph 4, wherein the information fields are included in downlink channel quality report (DCQR) and access stratum (AS) release assistant information (RAI) medium access control (MAC) control element (CE) (DCQR and AS RAI MAC CE).

[0324] Paragraph 6.　The method of any one of Paragraphs 3 to 5, wherein performing the RACH-less data transmission comprises: sending contention-based Msg3 to the entity.

[0325] Paragraph 7.　The method of any of one of Paragraphs 1 to 6, wherein the signal is Msg2 physical downlink control channel (PDCCH).

[0326] Paragraph 8.　The method of any one of Paragraphs 1 to 7, further comprising: disregarding the configuration to measure CQI when it is determined to perform the RACH-less data transmission procedure.

[0327] Paragraph 9.　The method of any one of Paragraphs 1 to 8, wherein controlling reporting of CQI based on the result of the determination comprises: reporting the CQI (e.g. in Msg3) when it is determined not to perform the RACH-less data transmission procedure.

[0328] Paragraph 10.　The method of Paragraph 1, wherein the signal is for a PDCCH used to schedule system information or for a PDCCH used for paging; and wherein controlling reporting of CQI based on the result of the determination comprises: reporting the CQI when performing the RACH-less data transmission procedure.

[0329] Paragraph 11.　The method of Paragraph 10, further comprising: performing RACH-less data transmission, the RACH-less data transmission including a stored CQI value.

[0330] Paragraph 12.　The method of Paragraph 11, wherein the stored CQI value is one of: a stored value of a CQI measurement on the PDCCH used to schedule system information, an average value of a number of stored values of CQI measurements (e.g. on different PDCCH used to schedule system information), a maximum value among a number of stored values of CQI measurements (e.g. on different PDCCH used to schedule system information), or a minimum value among a number of stored values of CQI measurements (e.g. on different PDCCH used to schedule system information).

[0331] Paragraph 13.　The method of any one of Paragraphs 10 to 12, further comprising: if the system information is SystemInformationBlockType31, measuring the CQI on the signal before (e.g. just before, or a set time before, or within a set period before) accessing.

[0332] Paragraph 14.　The method of any one of Paragraphs 10 to 13, further comprising: receiving (e.g. by broadcast) system information (e.g. SIB1 message or SIB2 message) to configure the UE to measure CQI on the signal.

[0333] Paragraph 15.　The method of any one of Paragraphs 10 to 14, wherein the CQI is derived from RSRP measurements used to estimate UE coverage level.

[0334] Paragraph 16.　The method of any one of Paragraphs 10 to 15, wherein a carrier or narrowband on which the CQI measurement is performed is the same as a carrier or narrowband, respectively, on which the RACH-less data transmission is attempted on.

[0335] Paragraph 17.　The method of Paragraph 1, wherein the signal is for a PDCCH used to schedule system information or for a PDCCH used for paging; and wherein controlling reporting of CQI based on the result of the determination comprises: when it is determined to perform the RACH-les data transmission procedure, performing the RACH-less data transmission procedure, including performing RACH-less data transmission, without reporting the CQI when a carrier or narrowband on which the CQI measurement is performed is different to a carrier or narrowband, respectively, on which the RACH-less data transmission is attempted on.

[0336] Paragraph 18.　The method of any one of Paragraphs 10 to 16, further comprising: sending, to the entity, an indication of the signal on which the CQI is measured.

[0337] Paragraph 19.　The method of any one of Paragraphs 1 to 18, further comprising: re-using a stored CQI value when reporting the CQI, based on the UE being previously connected to the entity.

[0338] Paragraph 20.　The method of Paragraph 1, wherein controlling reporting of CQI based on the result of the determination comprises: if it is determined to perform the RACH-less data transmission procedure, performing RACH-less data transmission without reporting CQI; and wherein the method further comprises: sending a -Complete message or Msg5 to the entity, the -Complete message or Msg5 including the CQI.

[0339] Paragraph 21.　The method of Paragraph 20, wherein the signal is for PDCCH of Msg4.

[0340] Paragraph 22.　The method of Paragraph 20 or Paragraph 21, wherein the UE is configured (e.g. by the network and / or in system information) to report the CQI in the -Complete message or Msg5.

[0341] Paragraph 23.　A UE configured to perform the method of any one of Paragraphs 1 to 22.

[0342]

Claims

1.A method performed by a user equipment (UE), the method comprising:receiving information for configuring the UE to report a downlink channel quality;identifying a carrier associated with a downlink channel quality measurement;determining whether a contention-based Msg3 is transmitted on the carrier associated with the downlink channel quality measurement; andin case that the contention-based Msg3 is transmitted on the carrier associated with the downlink channel quality measurement, transmitting a result of the downlink channel quality measurement in the contention-based Msg3.2.The method of claim 1, wherein the UE is in a radio resource control (RRC) idle state.3.The method of claim 1 or 2,wherein in case that the contention-based Msg3 is not transmitted on the carrier associated with the downlink channel quality measurement, the result of the downlink channel quality measurement is not transmitted in the contention-based Msg3.4.The method of any one of claims 1 to 3, wherein the UE is a narrowband-internet of things (NB-IoT) UE.5.The method of any one of claims 1 to 4, wherein the information is included in system information received from a network entity.6.The method of claim 5, wherein the information is included in a cqi-Reporting field in a system information block 2 narrowband (SIB2-NB).7.The method of any one of claims 1 to 6, wherein the contention-based Msg3 is transmitted without a Msg1 transmission and a Msg2 reception.8.A user equipment (UE) configured to perform the method according to any one of claims 1 to 7.9.A method performed by a network entity, the method comprising:transmitting, to a user equipment (UE), information for configuring the UE to report a downlink channel quality, wherein the information causes the UE to:identify a carrier associated with a downlink channel quality measurement,determine whether a contention-based Msg3 is transmitted on the carrier associated with the downlink channel quality measurement, andin case that the contention-based Msg3 is transmitted on the carrier associated with the downlink channel quality measurement, transmit a result of the downlink channel quality measurement in the contention-based Msg3.10.The method of claim 9, wherein the UE is in a radio resource control (RRC) idle state.11.The method of claim 9 or 10,wherein in case that the contention-based Msg3 is not transmitted on the carrier associated with the downlink channel quality measurement, the result of the downlink channel quality measurement is not transmitted in the contention-based Msg3.12.The method of any one of claims 9 to 11, wherein the UE is a narrowband-internet of things (NB-IoT) UE.13.The method of any one of claims 9 to 12, wherein the information is included in system information.14.The method of claim 13, wherein the information is included in a cqi-Reporting field in a system information block 2 narrowband (SIB2-NB).15.A network entity configured to perform the method according to any one of claims 9 to 14.

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