Methods for extending k-mac in a non-terrestrial network

Abstract

The disclosure relates to a 5G or 6G communication system for supporting a higher data transmission rate. According to an example of the disclosure, there is provided a method of a UE in a network, the method comprising: transmitting, to a base station (BS), capability information related to supported bands; receiving, from the BS, satellite assistance information for neighbour cells, wherein the satellite assistance information for neighbor cells includes information for extended k-Mac, wherein in case that a specific band is supported based on the capability information related to supported bands, the extended k-Mac is supported, wherein the extended k-Mac is a scheduling offset that is used if uplink and downlink timing is not aligned, wherein a maximum value of the extended k-Mac is larger than 512.

Description

METHODS FOR EXTENDING K-MAC IN A NON-TERRESTRIAL NETWORK

[0001] Certain examples of the present disclosure provide various techniques relating to extending k-Mac, in particular in a non-terrestrial network (NTN), for example within 3rdGeneration Partnership Project (3GPP) 5th Generation (5G) New Radio (NR) and later generation networks.

[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 BWP (BandWidth Part), new channel coding methods such as a LDPC (Low Density Parity Check) 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 V2X (Vehicle-to-everything) 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, NR-U (New Radio Unlicensed) 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, IAB (Integrated Access and Backhaul) 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 DAPS (Dual Active Protocol Stack) handover, and two-step random access for simplifying random access procedures (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 AR (Augmented Reality), VR (Virtual Reality), MR (Mixed Reality) 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 OAM (Orbital Angular Momentum), and RIS (Reconfigurable Intelligent Surface), 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 AI (Artificial Intelligence) 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] Embodiments of the present disclosure is to provide an apparatus and method for effectively providing a service in a wireless communication system.

[0009] 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.

[0010] According to a first aspect of the disclosure, there is provided a method of a first network entity (e.g. a UE) in a network (e.g. a NTN, an IoT NTN, an A2G network), the method comprising: obtaining information indicating use of an extended k-Mac by at least one cell; wherein the information indicating use of an extended k-Mac by at least one cell is received in at least one of: system information (e.g. SIB31, SIB31-NB, SIB1), ephemeris information, satellite assistance information, and neighbouring cell signalling (e.g. SIB32, SIB33).

[0011] According to an example, the information indicating use of an extended k-Mac by at least one cell comprises at least one of: information indicating that the at least one cell is using extended k-Mac, information indicating that the cell operates in a multi-hop mode, and information indicating an extended k-Mac value used by the at least one cell.

[0012] According to an example, the information indicating an extended k-Mac value used by the at least one cell comprises at least one of: an absolute extended k-Mac value, an additive extended k-Mac value, a multiplicative extended k-Mac value.

[0013] According to an example, the method further comprises: determining that at least one cell uses extended k-Mac; determining, if the first network entity supports extended k-Mac, if the first network entity is barred from the at least one cell based on a cellBarred indication only applicable to network entities supporting extended k-Mac.

[0014] According to an example, the cellBarred indication only applicable to network entities supporting extended k-Mac is received in system information (e.g. SIB1).

[0015] According to an example, the method further comprises performing a cell selection or cell reselection procedure based on the information indicating use of an extended k-Mac by the least one cell.

[0016] According to an example, performing a cell selection or cell reselection procedure based on information indicating use of an extended k-Mac by at least one cell comprises: determining that at least one cell uses extended k-Mac; determining, if the first network entity does not support extended k-Mac, if the first network entity is barred from the cell using extended k-Mac based on existing cellBarred indications.

[0017] According to an example, performing a cell selection or cell reselection procedure based on information indicating use of an extended k-Mac by at least one cell comprises: determining that at least one cell uses extended k-Mac based on the information indicating use of an extended k-Mac by at least one cell; and in response to determining that at least one cell uses extended k-Mac, performing at least one of: not searching for the at least one cell using extended k-Mac, deprioritizing the at least one cell using extended k-Mac, and considering the at least one cell using extended k-Mac to be barred.

[0018] According to an example, the method further comprises determining whether a further condition is satisfied; and in response to determining that at least one cell uses extended k-Mac and that the further condition is satisfied, performing at least one of: not searching for the at least one cell using extended k-Mac, deprioritizing the at least one cell using extended k-Mac, and considering the at least one cell using extended k-Mac to be barred.

[0019] According to an example, performing a cell selection or cell reselection procedure based on information indicating use of an extended k-Mac by at least one cell comprises: determining that at least one cell uses an extended k-Mac value greater than a threshold based on the information indicating use of an extended k-Mac by at least one cell; and in response to determining that at least one cell uses extended k-Mac, performing at least one of: not searching for the at least one cell using an extended k-Mac value greater than the threshold, deprioritizing the at least one cell using an extended k-Mac value greater than the threshold, and considering the at least one cell using an extended k-Mac value greater than the threshold to be barred.

[0020] According to an example, the method further comprises determining whether a further condition is satisfied; and in response to determining that at least one cell uses extended k-Mac and that the further condition is satisfied, performing at least one of: not searching for the at least one cell using an extended k-Mac value greater than the threshold, deprioritizing the at least one cell using an extended k-Mac value greater than the threshold, and considering the at least one cell using an extended k-Mac value greater than the threshold to be barred.

[0021] According to an example, the further condition comprises at least one of: determining that at least one other cell does not use extended k-Mac, determining that at least one other cell does not use an extended k-Mac value greater than the threshold, determining that the first network entity is configured to perform a cell selection or cell reselection procedure based on information indicating use of an extended k-Mac; determining that a service or traffic of the first network entity is a predetermined type (e.g. delay intolerant type, voice type, emergency type).

[0022] According to an example, the method further comprises performing a random access procedure with a first cell based on the extended k-Mac value indicated by the information indicating the extended k-Mac value used by the first cell.

[0023] According to an example, the method further comprises determining if information indicating a k-Mac value is signalled for a first cell; determining if information indicating an extended k-Mac value is signalled for the first cell; using the signalled extended k-Mac value for the first cell in response to determining that information indicating a k-Mac value is not signalled for the first cell and that information indicating an extended k-Mac value is signalled for the first cell; using the signalled k-Mac value for the first cell in response to determining that information indicating a k-Mac value is signalled for the first cell and that information indicating an extended k-Mac value is not signalled for the first cell; and using a default k-Mac value for the first cell in response to determining that information indicating a k-Mac value is not signalled for the first cell and that information indicating an extended k-Mac value is not signalled for the first cell.

[0024] According to a second aspect of the disclosure, there is provided a method of a second network entity (e.g. a base station) in a network (e.g. a NTN, an IoT NTN, an A2G network), the method comprising: transmitting, to a first network entity (e.g. a UE) information indicating use of an extended k-Mac by at least one cell; wherein the information indicating use of an extended k-Mac by at least one cell is transmitted in at least one of: system information (e.g. SIB31, SIB31-NB, SIB1), ephemeris information, satellite assistance information, and neighbouring cell signalling (e.g. SIB32, SIB33).

[0025] According to an example, the method further comprises determining that the at least one cell applies extended k-Mac; and transmitting, in response to determining that the at least one cell applies extended k-Mac, the information indicating use of the extended k-Mac by the at least one cell.

[0026] According to an example, the information indicating use of the extended k-Mac by the at least one cell is transmitted in system information; and wherein transmitting, in response to determining that the at least one cell applies extended k-Mac, the information indicating use of the extended k-Mac by the at least one cell comprises initiating a system information update procedure in response to determining that the at least one cell applies extended k-Mac.

[0027] According to a third aspect of the disclosure, there is provided a method of a first network entity (e.g. a UE), the method comprising: transmitting, to a second network entity, at least one of: information indicating that the first network entity supports a specific frequency band, wherein an indication that the first network entity supports a specific frequency band means that the first network entity supports extended k-Mac, information indicating that the first network entity supports internet of things (IoT) non-terrestrial network (NTN) time division duplex (TDD), and information indicating capability of the first network entity to support extended k-Mac.

[0028] According to a fourth aspect of the disclosure, there is provided a method of a second network entity (e.g. a base station), the method comprising: determining whether a first network entity (e.g. a UE) supports extended k-Mac; wherein determining whether the first network entity supports extended k-Mac comprises determining that the first network entity supports extended k-Mac based on receiving, from the first network entity, at least one of:

[0029] information indicating that the first network entity supports a specific frequency band,

[0030] information indicating that the first network entity supports internet of things (IoT) non-terrestrial network (NTN) time division duplex (TDD), and information indicating capability of the first network entity to support extended k-Mac.

[0031] According to a fifth aspect of the disclosure, there is provided a first network entity (e.g. a UE) configured to operate according to a method of the first aspect or third aspect, or any one of the above-described examples related to the first aspect or third aspect.

[0032] According to a sixth aspect of the disclosure, there is provided a second network entity (e.g. a base station) configured to operate according to a method of the second aspect or fourth aspect or any one of the above-described examples related to the second aspect or fourth aspect.

[0033] According to a seventh aspect of the disclosure, there is provided a network (e.g. a NTN, an IoT NTN, an A2G network) or wireless communication system comprising a first network entity according to the fifth aspect and a second network entity according to the sixth aspect.

[0034] According to an eighth aspect of the disclosure, there is provided a computer program comprising instructions which, when the program is executed by a computer or processor, cause the computer or processor to carry out a method according to any one of the first to fourth aspects, or the above-described examples relating to the first to fourth aspects.

[0035] According to a ninth aspect of the disclosure, there is provided a computer or processor-readable data carrier having stored thereon a computer program according to the eighth aspect.

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

[0037] Embodiments of the present disclosure is to provide an apparatus and method for effectively providing a service in a wireless communication system.

[0038] FIG. 1a illustrates NTN Release 17 architecture and scenario.

[0039] FIG. 1b illustrates NTN release 19 regenerative architecture and scenario.

[0040] FIG. 2 illustrates an Air-To-Ground network.

[0041] FIG. 3 illustrates the TDD band to operate IoT NTN TDD over.

[0042] FIG. 4 illustrates the timing in a transparent NTN.

[0043] FIG. 5 illustrates an initial / random access procedure.

[0044] FIG. 6 illustrates multihop architecture in a transparent network non-terrestrial network.

[0045] FIG. 7 illustrates a UE procedure in accordance with an example of the present disclosure.

[0046] FIG. 8 illustrates an example method of a first network entity in a network.

[0047] FIG. 9 illustrates an example method of a second network entity in a network.

[0048] FIG. 10 illustrates an example method of a first network entity.

[0049] FIG. 11 illustrates an example method of a second network entity.

[0050] FIG. 12 illustrates an exemplary network entity (e.g. UE or base station) that may be used in examples of the present disclosure.

[0051] Non-Terrestrial Network

[0052] NR NTN (NR_NTN_solutions-Core) [RP-211557] was a 3GPP Work Item in 3GPP Release 17 to define solution enable New Radio (NR) and NG-RAN support Non-Terrestrial Networks. It addressed solutions for Transparent payload for both Geostationary and non-Geostationary network scenarios, with the UE having GNSS capability and the satellite beams being both earth-fixed or earth-moving.

[0053] FIG. 1a illustrates NTN Release 17 architecture and scenario.

[0054] FIG. 1b illustrates NTN release 19 regenerative architecture and scenario.

[0055] IoT NTN was a 3GPP study and work item in 3GPP release 17 to provide Non-Terrestrial Network access for E-UTRAN IoT devices (NB-IoT and LTE-M / eMTC) [RP-202689]. And NR NTN was a work item in Rel-17 to specify adaptation to allow NR to function over NTN [RP-211557]. Non-Terrestrial Network access may be served via satellites that are in Lower Earth Orbit (LEO), Medium Earth Orbit (MEO) and Geostationary Orbit (GEO), as well as through High-Altitude Platform Systems (HAPS).

[0056] Following the Work items in Release 17 there were work items to enhance NR NTN [RP-220953] and IoT NTN [RP-220979] in Release 18.

[0057] NR NTN phase 3 [RP-234078] is a 3GPP Work Item in 3GPP Release 19 aiming to enhance NR NTN with a range of enhancements:

[0058] * Downlink coverage enhancements

[0059] * Uplink capacity and throughput enhancements by using Orthogonal Coverage Codes

[0060] * MBS broadcast over NTN

[0061] * Introduction of regenerative payload

[0062] * Redcap and NTN enhancements

[0063] * Terrestrial E-UTRAN to NR NTN mobility

[0064] Air-To-Ground network

[0065] An Air-To-Ground (abbreviated as ATG or A2G) network is a cellular network that provides connectivity in the air via base stations on the ground. It is different from a Non-Terrestrial Network as the access link is from the ground to the UE in the sky, where as in NTN the access link is from space / sky to the ground, as seen in FIG. 2 which illustrates an Air-To-Ground network.

[0066] One of the main use cases of ATG network is to provide backhaul connectivity to　 access points in aircraft.

[0067] A Study item was started in Rel-18 [RP-221369] in RAN4 to define requirements for coexistence between ATG and IMT terrestrial networks. Furthermore to define RRM performance requirements for ATG UE, demodulation performance requirements for ATG BS / UE, and test procedures for ATG BS conformance testing.

[0068] Bands for NR NTN

[0069] For Rel-17, RAN4 introduced basic support for NTN on lower frequency bands. These are the bands n254, n255 and n256, which have the following characteristics:

[0070] * Band n254 in FDD mode:

[0071] ** UL operating band 1610 - 1626.5 MHz

[0072] ** DL operating band 2483.5 - 2500 MHz

[0073] * Band n255 in FDD mode:

[0074] ** UL operating band 1626.5 - 1660.5 MHz

[0075] ** DL operating band 1525 - 1559 MHz

[0076] * Band n256 in FDD mode:

[0077] ** UL operating band 1980 - 2010 MHz

[0078] ** DL operating band 2170 - 2200 MHz

[0079] For Rel-18, RAN4 has introduced support for NTN for higher frequencies. RAN4 defined FR2-NTN as frequencies in between 17.3 to 30 GHz [38.101-5, V18.5.0], where as FR1-NTN remains in lower band 410 MHz to 7.125 GHz.

[0080] RAN4 introduced the following set of bands for FR2-NTN [38.101-5, V18.5.0]:

[0081] * Band n510 in FDD mode:

[0082] ** UL operating band 27500 - 30000 MHz

[0083] ** DL operating band 17300 - 20200 MHz

[0084] * Band n511 in FDD mode:

[0085] ** UL operating band 28350 - 30000 MHz

[0086] ** DL operating band 17300 - 20200 MHz

[0087] * Band n512 in FDD mode:

[0088] ** UL operating band 27500 - 28350 MHz

[0089] ** DL operating band 17300 - 20200 MHz

[0090] For these bands, SCS of 60 kHz and 120 kHz were introduced [38.101-5, V18.5.0]:

[0091] -------------------------- 38.101-5 V18.5.0 --------------------------

[0092] Table 5.3.2-2:　Maximum transmission bandwidth configuration NRBfor FR2-NTN

[0093]

[0094] -------------------------- 38.101-5 V18.5.0 --------------------------

[0095] NTN system information

[0096] 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) were needed.

[0097] NR NTN have defined the following SIBs for NTN:

[0098] * SIB19: This contains the most important information required for operation in a non-terrestrial network including serving, neighbour cell ephemeris and timing related parameters.

[0099] * SIB25: This contains information to assist in relaxation of neighbour cell measurements of terrestrial cells when a UE is camping on an NTN cell.

[0100] IoT NTN have defined the following SIBs for NTN:

[0101] * SIB31(-NB): This contains the most important information required for operation in a non-terrestrial network such as serving cell ephemeris and timing related parameters.

[0102] * SIB32(-NB): This contains parameters for discontinuous coverage operation, which mostly consist of long term orbital parameters to predict when in time an upcoming satellite pass will occur.

[0103] * SIB33(-NB): This consists of neighbouring satellite assistance information mainly for the purpose of neighbour cell measurements.

[0104] The system information contains the following:

[0105] * Serving cell Ephemeris elements - which allows UE to calculate the satellite position for doppler and time pre-compensation. This can be of two formats:

[0106] ** PVT format - which describes a (X,Y,Z) position as well as a speed vector (vX, vY, vZ)

[0107] ** Orbital parameters - this describes the orbital movements of the satellite which is then used to infer the satellite position

[0108] * 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)

[0109] ** Absolute TA common, taking up 23 bits

[0110] ** Drift of the TA common - how the TA common drifts, i.e. the first derivative, taking up 19 bits

[0111] ** Variation of the TA common - how the TA common varies, i.e. the second derivative of the TA common, taking up 15 bits

[0112] * Synchronization validity duration - used to define how long the ephemeris and TA common is valid

[0113] * Epoch time - when the synchronization validity duration should start

[0114] * K-Offset - scheduling offset for timing relationship in NTN

[0115] * K-Mac - Scheduling offset used when the downlink and uplink frame timing is not aligned

[0116] *NR NTN specific information also includes (as part of 38.331):

[0117] ** T-Service (signaled in SIB3 in IoT NTN)

[0118] ** Reference location and distance threshold - used for location-based measurement initiation in RRC IDLE and RRC Connected mode

[0119] ** Neighbour cell ephemeris

[0120] *** This is used for idle mode measurements

[0121] IoT NTN TDD

[0122] IoT NTN is a work item (RP-243293) in 3GPP Release 19 to specify NB-IoT non-terrestrial network operation in a band with a TDD-structure that is different from 3GPP TDD. The work item description has the following objectives:

[0123] * Specify a new NB-IoT TDD NTN mode based on minimum necessary changes to the NB-IoT NTN FDD frame structure and procedures,　 including:

[0124] ** Definition, configuration (if needed) and signaling (if needed) of the periodic pattern, necessary adaptation (if needed) and associated UE procedures [RAN1, RAN2]

[0125] *** Support a pattern with a period of 9 radio frames for the target mobile satellite services (MSS) allocated band, where D=U=8 with a fixed guard period.RAN1 to consider whether there is a need for a mechanism to achieve an adjustable guard period for the purpose of allowing deployment with the TDD frame structure of the legacy system operating in the target MSS allocated band.

[0126] ** Other necessary impacts on higher layers [RAN2]

[0127] ** RRM and RF core requirements [RAN4]

[0128] * Specify a new NB-IoT TDD operating NTN band for the MSS allocation spanning 1616-1626.5 MHz for DL and UL, based on the outcome of the study, to be used as example band for this WI [RAN4].

[0129] ** Specify band numbering

[0130] ** Specify SAN and UE RF characteristics

[0131] ** Specify DL and UL channelization.

[0132] ** Specify channel bandwidth as 200 kHz

[0133] ** Note1: No NTN-NTN coexistence study needed.

[0134] ** Note2: Leverage existing work as much as possible for TN-NTN coexistence of adjacent bands

[0135] The TDD operation of the specific band can be seen in FIG. 3, which illustrates the TDD band to operate IoT NTN TDD over.

[0136] There are a number of differences between this type of TDD operation compared to a typical 3GPP-like TDD band. First of all, the periodicity of the TDD is 90 ms, which is unusual periodicity in 3GPP, where typical time-related durations are either a multiple of 2 or 10 or both 2 and 10. For instance the system frame number (SFN) is 10 subframes, the Hyper SFN is 1000 SFNs, etc. Each uplink or downlink frame is ~8 milliseconds long, and the boundary between the uplink slots cannot be crossed - it is not possible to transmit a ~16 millisecond long transmission. Another difference is that it is expected that only a single uplink and downlink frame will be available every 90 ms, as already existing services using other waveforms should co-exist on the other frames. The result of this is low duty cycles.

[0137] NTN timing

[0138] The timing in a transparent NTN can be seen in FIG. 4.

[0139] The TTA is what the UE estimates based on the UE position, the position of the satellite (computed via the acquired ephemeris) as well as the Common TA. The Common TA is also signalled along with the first and second derivative of its change.

[0140] The full TTAfor NR NTN is:

[0141]

[0142] The full TTAfor IoT NTN is:

[0143]

[0144] Where the component is based on UE position, satellite ephemeris and Common TA.

[0145] k-Mac is a scheduling offset that is used if the uplink and downlink timing is not aligned at the base station, which is approximately equal to the RTT between the Reference Point (RP) and the base station.

[0146] The k-Offset is a configured scheduling offset that is larger or equal to the sum of the service link RTT (also referred to as the access link RTT in FIG. 4) and the common TA. The k-Offset among different things tell the UE when the uplink transmission timing shall apply. The cell specific k-Offset is broadcasted while the UE specific, some times referred to as the differential k-Offset, can be configured via MAC CE. The full k-Offset is then calculate as k-Offset_cell - k-Offset_MACCE.

[0147] All of these parameters are signalled in SIB19.

[0148] There is furthermore the UE-gNB / eNB RTT internal value. This is the sum of the UEs timing advance value, which is partly estimated, and the k-Mac. This is used in order to delay certain procedures in the MAC specifications. For instance, after having sent a preamble, msg1, the UE waits UE-gNB / eNB RTT before monitoring for a response. Similar is done for monitoring for Msg4 after sending Msg3 as well as during DRX procedures when the UE monitors for new scheduling and / or ACK / NACKs.

[0149] Initial / random access procedure in NTN

[0150] Initial / random access procedure can be seen in FIG. 5. The steps are normally as follows:

[0151] 1. UE determines the timing advance pre-compensation using the UE position and the satellite position. The UE position via GNSS, but other methods that does 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.

[0152] 2. UE uses the pre-compensation and sends Msg1 which is the RACH 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.

[0153] 3. If the network is able to detect and the determine the RACH preamble, the eNB responds with Msg2 or RAR. The UE monitors for the Msg2 or RAR during the random access response window. This window has a configurable length and in NTN, it is started roughly UE-gNB / eNB RTT after having sent the Msg1.

[0154] 4. UE sends Msg3, which is sent using PUSCH. This message will contain 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.

[0155] 5. Since it is possible that two UEs select the same RAPID, there is a chance of collision. So in Msg4, sent over PDSCH 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. Monitoring for Msg4 is done in the MAC contention resolution timer, which is started UE-gNB / eNB RTT after sending the Msg3.

[0156] 6. 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.

[0157] Idle and inactive mode operation

[0158] Idle and inactive mode mobility is based on a UE autonomously performing measurements and deciding according to some rules whether a UE shall re-select to another cell or not to camp on.

[0159] During cell selection, the UE identifies suitable cells, which is according to a cell suitability criteria based on signal strength and signal quality measurements. After identifying one or several suitable cells, the UE can choose any of them. For instance the UE can select the cell with the strongest signal strength and signal quality within a PLMN. Cell selection can performed following PLMN selection (which may be after a UE is turned on), after being released by a network, or during the RRC re-establishment procedure and a number of other cases.

[0160] A cell may be classified into a number of different types of cells. A suitable cell is a cell that fulfills the cell selection criteria, the cell is not barred etc. and is part of the tracking area of the UE - thus a normal type of cell. An acceptable cell is a cell on which the UE is only allowed to camp for specific reasons such as emergency cases, but the cell cannot be barred and the cell selection criteria need to be fulfilled. A UE only camps on such a cell if it cannot find a suitable cell. A reserved cell is a reserved if the system information indicates that it is reserved.

[0161] When camped on a cell, the UE shall perform the cell reselection procedures which includes searching and detecting cells and camping on a better or more suitable cell.

[0162] In the cell reselection procedure, the UE searches intra-frequency cells, inter-frequencies cells and inter-RAT cells following the signalling by the serving cell. Each frequency (inter-RAT or intra-RAT) may have a specific cell reselection priority. The cell reselection algorithm is designed to ensure that the UE chooses a cell with highest priority, given that it is not barred or not allowed to camp on. A UE shall always select an inter-frequency or inter-RAT cell with a higher priority over a lower priority cell. If frequencies of equal priority are detected, then the UE shall rank all of the cells, where the ranking metric is based on signal strength and signal quality measurements and then choose the best candidate. The UE then camps on the newly re-selected cell.

[0163] There are also certain rules on for how long a new cell shall be better than the serving cell before camping on the new cell. This parameter is called Treselection and can be specific for a RAT or for other cases. There are also thresholds for the signal strength of signal quality that may need to be fulfilled before selecting a new cell to camp on, which may depend on whether the cell is lower or higher priority, and depend on whether the cell is inter-frequency or inter-RAT.

[0164] As part of the idle mode and inactive procedures, the UE also checks whether a cell is barred or not. If a cell is barred, the UE is not allowed to connect to the cell, not allowed to camp or consider the cell for cell reselection. The barring bit, which is used for the first release of the UE may be signalled in MIB or in SIB1, depending on the RAT. In 4G LTE, eMTC and NB-IoT, the barring bit is in SIB1 and in MIB for 5G NR. However, other barring bits may be signalled in SIB1. This is for instance for cases where the cell is not backwards compatible.

[0165] Inter-RAT may be considered any other than the current RAT. As an example for 4G E-UTRA UE, the following may be considered inter-RAT: 2G, 3G, 4G NB-IoT, 5G NR or 6G.

[0166] Inter-RAT may be considered any other than the current RAT. As an example for 4G E-UTRA UE, the following may be considered inter-RAT: 2G, 3G, 4G NB-IoT, 5G NR or 6G.

[0167] The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present invention.

[0168]

[0169] The following description of examples of the present disclosure, with reference to the accompanying drawings, is provided to assist in a comprehensive understanding of the present invention, as defined by the claims.　 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.

[0170] The same or similar components may be designated by the same or similar reference numerals, although they may be illustrated in different drawings.

[0171] 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.

[0172] 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 examples disclosed herein.

[0173] Throughout the description and claims, the words "comprise", "contain" and "include", and variations thereof, for example "comprising", "containing" and "including", means "including but not limited to", and is not intended to (and does not) exclude other features, elements, components, integers, steps, processes, functions, characteristics, and the like.

[0174] Throughout the description and claims, 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.

[0175] Throughout the description and claims, language in the general form of "X for Y" (where Y is some action, process, function, activity or step and X is some means for carrying out that action, process, function, activity or step) encompasses means X adapted, configured or arranged specifically, but not necessarily exclusively, to do Y.

[0176] Features, elements, components, integers, steps, processes, functions, characteristics, and the like, described in conjunction with a particular aspect, embodiment, example or claim are to be understood to be applicable to any other aspect, embodiment, example or claim disclosed herein unless incompatible therewith.

[0177] 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.

[0178] 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. For example, the functionality of a UE, base station, cell, or satellite in the examples below may be applied to any other suitable type of entity performing functions of a UE, base station, cell, or satellite, respectively.

[0179] The skilled person will appreciate that certain examples of the present disclosure may not be directly related to standardization but rather proprietary implementation of some of the extended k-Mac functions of NR Rel-17 and beyond networks.

[0180] The skilled person will appreciate that the present invention is not limited to the specific examples disclosed herein. For example:

[0181] * The techniques disclosed herein are not limited to 3GPP 5G.

[0182] * The techniques disclosed herein are not limited to NTN.

[0183] * 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.

[0184] * 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.

[0185] * One or more further elements, entities and / or messages may be added to the examples disclosed herein.

[0186] * One or more non-essential elements, entities and / or messages may be omitted in certain examples.

[0187] * 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.

[0188] * 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.

[0189] * Information carried by a particular message in one example may be carried by two or more separate messages in an alternative example.

[0190] * Information carried by two or more separate messages in one example may be carried by a single message in an alternative example.

[0191] * The order in which operations are performed may be modified, if possible, in alternative examples.

[0192] * 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.

[0193] 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.

[0194] 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, claim, example and / or embodiment disclosed herein. Certain embodiments of the present disclosure provide a machine-readable storage storing such a program.

[0195] As part of the IoT NTN TDD work item, there have been proposals to introduce an extended k-Mac. One of the purposes to introduce this is to enable multihop architecture in a transparent network non-terrestrial network. This is because in some cases a satellite may not have a ground gateway to perform processing and in these cases the only option in a transparent architecture would be to have multiple hops to reach a ground gateway. This can be seen in FIG. 6

[0196] However, one issue is that k-Mac is a fundamental parameter for the access procedures, so careful considerations need to be made to consider backwards compatibility. Aspects of the present disclosure are intended to address some of these issues.

[0197] Aspects of the present disclosure include methods for supporting extended k-Mac.

[0198] Aspects of the present disclosure are described using eNBs and from the perspective of NB-IoT (IoT NTN), but the disclosure may equally apply to gNBs or NG-RAN (5G NR), or even 6G RAN. The disclosure may also apply to a eMTC / LTE-M / NB-IoT UE, or 5G NR UE, or E-UTRAN UE. The disclosure may also apply to any type of Air-to-Ground or High Altitude Platform system.

[0199] The methods in this disclosure may also apply if other types of timing related parameters are changed. For instance if k-Offset is changed, many of the below methods may apply, as well as common TA. For instance, if multiple parameters of the common TA is implemented, or if the common TA is extended or made more precise.

[0200] Extending k-Mac

[0201] In examples of the present disclosure, several methods are introduced for supporting an extended k-Mac. The extended k-Mac can for instance extend the k-Mac beyond its original maximum value of 512 slots / subframes / milliseconds. This can for instance be done by signalling a new value. For example, the UE may obtain information indicating use of an extended k-Mac by at least one cell (or satellite), wherein the information indicates an extended k-Mac value. The new value (i.e. the extended k-Mac value) may be a new absolute value, an additive value or a multiplicative value. The new extended value can be in any type of time unit, such as slots, subframes, symbols in any subcarrier spacing (7.5, 15, 30, 45, 60, 120, 240 or 480 kHz) or milliseconds or microseconds. If the extended value is an additive value, this may mean that the extended value is added to the already introduced k-Mac. Thus the final k-Mac value to be used (k-Mac-final) would be equal to k-Mac + k-Mac-Ext. If the extended value is a multiplicative value, this may mean that the extended value is multiplied by the already introduced k-Mac. Thus the final k-Mac value to be used (k-Mac-final) would be equal to k-Mac Х k-Mac-Ext. If the extended value is an absolute value, the extended value may replace the already introduced k-Mac. That is, k-Mac final = k-Mac-Ext. If the extended value has a different unit than the original value, then the additive value may be first converted to absolute time.

[0202] The extended k-Mac may be signalled in system information, for example in SIB31 / SIB31-NB, in SIB1 or in any other SIB. The k-Mac may also be extended for any neighbouring cell signalling. This may mean that it would be a part of SIB32, SIB33 or any other neighbour cell or satellite assistance information.

[0203] If the already introduced k-Mac is not signalled, then in the prior art the UE will be configured to assume a value of 0. Thus if the k-Mac is not configured, then the UE may not assume a k-Mac of 0 if the extended k-Mac is signalled. In other words, if the k-Mac is not signalled, then the UE may use the extended k-Mac, if signalled, else the UE assumes a value of 0 for k-Mac. This example can be seen in Specification example 2 for serving satellite and specification example 4 for neighbouring satellite.

[0204] For example, the UE may determine whether information indicating a k-Mac value is signalled for a first cell (or satellite) and determine whether information indicating an extended k-Mac value is signalled for the first cell (or satellite). The UE may use the signalled extended k-Mac value for the first cell (or satellite) in response to determining that information indicating a k-Mac value is not signalled for the first cell (or satellite) and that information indicating an extended k-Mac value is signalled for the first cell (or satellite). The UE may use the signalled k-Mac value for the first cell (or satellite) in response to determining that information indicating a k-Mac value is signalled for a first cell (or satellite) and that information indicating an extended k-Mac value is not signalled for the first cell (or satellite). The UE may use a default k-Mac value for the first cell (or satellite) in response to determining that information indicating a k-Mac value is not signalled for a first cell (or satellite) and that information indicating an extended k-Mac value is not signalled for the first cell (or satellite).

[0205] In some cases, if the extended k-Mac is indicated for a neighbouring satellite or cell, then this may be indicated in a separate list of satellites or cells. This can be important as some UEs that do not supported extended k-Mac may not need to search, detect or measure for satellites that are operating with extended k-Mac. This may mean that a UE that do not support extended k-Mac will not be configured or able to parse information indicating satellites or cells that support or operate extended k-Mac. Similarly, only UEs that support extended k-Mac may search, detect or measure cells that operate with extended k-Mac. In other words, these UEs will be able to parse information indicating support or operation of extended k-Mac.

[0206] One issue with the extended k-Mac is that it is essential during the random access procedure for knowing how long that a UE for instance shall wait for the random access response after sending the Msg1. If there for instance are ambiguities of the k-Mac to apply, this may make access procedures not function at all. This means that there may not be much backwards compatibility if extended k-Mac is used.

[0207] One method of solving the issue, is that if UE supports a specific band, then the UE will be configured to support extended k-Mac. Such a band may for instance be the IoT NTN TDD band, but it may also be other bands. If it is the IoT NTN TDD band it may for instance be the band on 1616-1626.5 MHz, or any other band deploying or cell signaling that IoT NTN TDD is used.　This can mean that if the UE signals that it is capable of operating or supporting a specific band, then this means that the UE is capable of extended k-Mac. One example of this can be seen in specification example 3. Capable of extended k-Mac may thus mean that the UE is capable of access procedures and cell operation with extended k-Mac.

[0208] For example, a base station may determine that a UE supports extended k-Mac based on receiving, from the UE, information indicating that the UE supports a specific frequency band and / or information indicating that the UE supports IoT NTN TDD.

[0209] In some cases, the use of extended k-Mac may be sporadic and thus not always applied by a network. This means that there may be device that does not have support for it. In this case it may make sense to bar devices that do not have support for extended k-Mac. This can for instance be done by utilizing currently used barring bits such as cellBarred in MIB and cellBarred-NTN in SIB1. This bars all of the legacy UEs not supporting extended k-Mac.

[0210] So to solve this, in one example of the present disclosure, another cellBarred indication may be introduced for UEs supporting extended k-Mac. The UEs supporting extended k-Mac may use a new indication, for instance named cellBarred-K-Mac, to determine whether the UE is barred or not. This can have the values barred and notBarred. The UEs that support extended k-Mac may thus ignore the other barring indications. This barring indication may indicate whether NTN UEs capable of extended k-Mac shall be barred or not barred. The UE procedure can be seen in FIG. 7. The cell that supports the extended k-Mac or the cell that has configured an extended k-Mac may need to apply this cell barred indication. Thus the network that signals the extended k-Mac may need to apply this barring indication at the same time. The network may or may not also broadcast the cellBarred-NTN in SIB1 if this new indication is broadcasted. The cellBarred-NTN may be required for UEs to determine whether the cell is an NTN cell or not.

[0211] For example, a UE may determine, if the UE does not support extended k-Mac, whether the UE is barred from the cell using extended k-Mac based on existing cellBarred indications. If the UE does support extended k-Mac, the UE may determine whether the UE is barred from the cell using extended k-Mac based on a (new) extended k-Mac cellBarred indication.

[0212] If the system information is updated and the cell applies the extended k-Mac (i.e the extended k-Mac was not applied previously) then the network may have to initiate the system information update procedures. This is a procedure that requires the network to page UEs regarding the updated system information.

[0213] This for instance is valid in many deployments where the satellite network only performs multi-hop transmissions when operating over ocean, or over otherwise very remote areas without ground stations.

[0214] Other use of extended k-Mac

[0215] Extending k-Mac means that RTT can be increased compared to not extending the k-Mac. This means that the delay will be increased, which means that some services may be difficult to provide. This means that it may be useful for a network or a UE to take the extended k-Mac into account for several procedures to determine the service or access.

[0216] For instance, in examples of the present disclosure, an extended k-Mac can be used for the UE to deprioritize a cell, for instance during cell selection or cell reselection procedures when the UE is RRC_IDLE or RRC_INACTIVE. This may for instance mean that if the UE has determined that a cell has extended its k-Mac, the UE will deprioritize the cell and prioritize another cell that has not extended its k-Mac or has a lower k-Mac.

[0217] For example, when performing a cell selection or cell reselection procedure, the UE may determine that at least one cell (or satellite) uses extended k-Mac. In response to determining that at least one cell (or satellite) uses extended k-Mac, the UE may then deprioritize the at least one cell (or satellite) using extended k-Mac.

[0218] For example, when performing a cell selection or cell reselection procedure, the UE may determine that at least one cell (or satellite) uses an extended k-Mac value greater than a threshold value. In response to determining that at least one cell (or satellite) uses an extended k-Mac value greater than the threshold value, the UE may then deprioritize the at least one cell (or satellite) using an extended k-Mac value greater than the threshold value.

[0219] In examples of the present disclosure, a cell may indicate in a neighbour cell satellite information whether a cell is configured to extend the k-Mac. Alternatively, the extended k-Mac may also be signalled. This could for instance be used in the idle mode procedures, such as to deprioritize or view associated cells as barred. Deprioritizing a cell or satellite that has extended k-Mac may mean that UE will not search for the cell or the satellite, or that the UE will consider the cells with an extended k-Mac or high k-Mac as a lower priority compared to other cells without extended k-Mac.

[0220] For example, when performing a cell selection or cell reselection procedure, the UE may determine that at least one cell (or satellite) uses extended k-Mac. In response to determining that at least one cell (or satellite) uses extended k-Mac, the UE may then not search for the at least one cell (or satellite) using extended k-Mac, and / or may consider the at least one cell (or satellite) using extended k-Mac to be barred.

[0221] For example, when performing a cell selection or cell reselection procedure, the UE may determine that at least one cell (or satellite) uses an extended k-Mac value greater than a threshold value. In response to determining that at least one cell (or satellite) uses an extended k-Mac value greater than the threshold value, the UE may then not search for the at least one cell (or satellite) using an extended k-Mac value greater than the threshold value, and / or may consider the at least one cell using an extended k-Mac value greater than the threshold value to be barred.

[0222] If the UE views the cells as barred, this can be under the condition that there are other cells that either does not use an extended k-Mac or a high value k-Mac. In other words, the UE considers cells as barred if the cell information or satellite information indicates that an extended k-Mac is used if there are other cells that does not use extended k-Mac. This example can be seen in specification example 1. This could for instance be done by only considering satellites and its associated cells that does not broadcast extended k-Mac in SIB33 (SIB19 in NR NTN, in neighbouring satellite info) as not barred, if the at least one of the satellites in SIB33 broadcasts the extended k-Mac. Whether the UE may downprioritize or bar cells with extended k-Mac may be configurable. This can for instance be configurable in cell selection or cell reselection parameters, or in access parameters such as SIB1 or in NTN-related parameters such as SIB31 (SIB19 in NR NTN). In other words, the serving cell or the cell that the UE camps on may indicate whether it is allow to deprioritize neighbouring (or potentially also the serving / camping cell) that are configured with extended k-Mac.

[0223] For example, the UE may determine whether a further condition is satisfied; and in response to determining that at least one cell (or satellite) uses extended k-Mac (or an extended k-Mac value greater than the threshold value) and that the further condition is satisfied, the UE may not search / deprioritize / consider barred the at least one cell (or satellite) using extended k-Mac (or an extended k-Mac value greater than the threshold value). For example, the further condition may be determining that at least one other cell (or satellite) does not use extended k-Mac (or an extended k-Mac value greater than the threshold value) and / or determining that the UE is configured to perform a cell selection or cell reselection procedure based on information indicating use of an extended k-Mac.

[0224] If it is indicated in a satellite assistance information that it is using extended k-Mac, since this information is associated with an ephemeris information, which the UE can use to search for cells on a frequency, then if the extended k-Mac is signalled can be done by the UE not being required to search for the satellite using the ephemeris. Also, the satellite assistance information may be associated with a specific frequency. If one or more or all of the satellite assistance information elements associated with that frequency indicate that k-Mac is extended, then the UE may be configured to not measure or not be required to measure that specific frequency or RAT.

[0225] The signalling of the extended k-Mac can either indicate the exact value that the neighbouring satellite or neighbouring cells are using, or the signalling may indicate that the cell, cells or cells associated with the satellite are applying extended k-Mac and not the exact value. This may thus only be a single bit indication indicating that the cell, cells or cell associated with the satellite are applying extended k-Mac. The indication may also indicate whether the cell, cells or cells associated with the satellite may apply extended k-Mac. This may mean that extended k-Mac may not always be used.

[0226] For example, the UE may obtain information indicating use of an extended k-Mac by at least one cell (or satellite) wherein the information comprises at least one of information indicating that the at least one cell (or satellite) is using extended k-Mac, and information indicating an extended k-Mac value used by the at least one cell (or satellite).

[0227] Similarly, cells without extended k-Mac may be prioritized over cells that use extended k-Mac.

[0228] The downprioritization (or prioritization if not used) or the barring of a cell that uses an extended k-Mac may depend on the specific service that UE is serving. For instance, for latency tolerant traffic, the UE may not downprioritize the cells. For delay intolerant services, such as voice services and emergency cases, the UE may downprioritize the cells. The UE may also bar all of the cells that indicate extended k-Mac for voice services.

[0229] The cells that extend the k-Mac may for instance not be considered to support voice services, which may mean that these cells may not indicate support of IMS voice, voice over 5G / NR or IMS emergency calls. A UE with these services may still be allowed to camp on a cell with extended k-Mac for emergency purposes. For instance to receive public warning signalling, i.e. emergency messages that are broadcasted.

[0230] For example, the UE may determine whether a further condition is satisfied; and in response to determining that at least one cell (or satellite) uses extended k-Mac (or an extended k-Mac value greater than the threshold value) and that the further condition is satisfied, the UE may not search / deprioritize / consider barred the at least one cell (or satellite) using extended k-Mac (or an extended k-Mac value greater than the threshold value). For example, the further condition may be determining that a service or traffic of the UE is a predetermined type (e.g. delay intolerant type, voice type, emergency type).

[0231] Other aspects

[0232] A UE may indicate its capabilities to support an extended k-Mac to a network. This can for instance facilitate the UE being redirected or handed over to a cell that operates with extended k-Mac. The network may thus decide whether to handover or redirect the UE to an NTN cell / frequency / network that uses extended k-Mac depending on whether the UE supports extended k-Mac. This decision may be made by a source or target cell during a handover procedure.

[0233] For example, a base station may determine that a UE supports extended k-Mac based on receiving, from the UE, information indicating capability of the UE to support extended k-Mac.

[0234] Similarly, if the network indicates that the cell operates in a multi-hop mode, some aspects of the invention may be applicable. For instance, the network may indicate that the cell operates in a multi-hop mode, where the UE can use this information to determine that the k-Mac may be extended. The aspects related to barring and idle mode operation such as prioritization and support of certain services may all be applicable.

[0235] For example, the UE may obtain information indicating use of an extended k-Mac by at least one cell (or satellite) wherein the information comprises information indicating that the at least one cell (or satellite) operates in a multi-hop mode.

[0236] FIG. 8 illustrates an example method of a first network entity (e.g. a UE) in a network (e.g. a NTN, an IoT NTN, an A2G network).

[0237] In step 802, the method comprises obtaining information indicating use of an extended k-Mac by at least one cell.

[0238] The information indicating use of an extended k-Mac by at least one cell is received in at least one of: system information (e.g. SIB31, SIB31-NB, SIB1), ephemeris information, satellite assistance information, and neighbouring cell signalling (e.g. SIB32, SIB33).

[0239] FIG. 9 illustrates an example method of a second network entity (e.g. a base station) in a network (e.g. a NTN, an IoT NTN, an A2G network).

[0240] In step 902, the method comprises transmitting, to a first network entity (e.g. a UE) information indicating use of an extended k-Mac by at least one cell.

[0241] The information indicating use of an extended k-Mac by at least one cell is transmitted in at least one of: system information (e.g. SIB31, SIB31-NB, SIB1), ephemeris information, satellite assistance information, and neighbouring cell signalling (e.g. SIB32, SIB33).

[0242] FIG. 10 illustrates an example method of a first network entity (e.g. a UE).

[0243] In step 1002, the method comprises transmitting, to a second network entity, at least one of: information indicating that the first network entity supports a specific frequency band (wherein an indication that the first network entity supports a specific frequency band means that the first network entity supports extended k-Mac), information indicating that the first network entity supports internet of things (IoT) non-terrestrial network (NTN) time division duplex (TDD), and information indicating capability of the first network entity to support extended k-Mac.

[0244] FIG. 11 illustrates an example method of a second network entity (e.g. a base station).

[0245] In step 1102, the method comprises determining whether a first network entity (e.g. a UE) supports extended k-Mac.

[0246] Determining whether the first network entity supports extended k-Mac comprises determining that the first network entity supports extended k-Mac based on receiving, from the first network entity, at least one of: information indicating that the first network entity supports a specific frequency band, information indicating that the first network entity supports internet of things (IoT) non-terrestrial network (NTN) time division duplex (TDD), and information indicating capability of the first network entity to support extended k-Mac.

[0247] FIG. 12 is a block diagram of an exemplary network entity (e.g. UE or base station) that may be used in examples of the present disclosure. The skilled person will appreciate that the network entity illustrated in FIG. 12 may be implemented, for example, as a network element on a dedicated hardware, as a software instance running on a dedicated hardware, or as a virtualised function instantiated on an appropriate platform, e.g. on a cloud infrastructure.

[0248] The network entity 1200 comprises a processor 1201 (or controller), a transmitter 1203 and a receiver 1205. The receiver 1205 is configured for receiving one or more messages from one or more other network entities. The transmitter 1203 is configured for transmitting one or more messages to one or more other network entities. The processor 1201 is configured for performing operations as described above.

[0249] According to an example, there is provided a method of a first network entity (e.g. a UE) in a network (e.g. a NTN, an IoT NTN, an A2G network), the method comprising: obtaining information indicating use of an extended k-Mac by at least one cell.

[0250] According to an example, the method further comprises performing a cell selection or cell reselection procedure based on the information indicating use of an extended k-Mac by the least one cell.

[0251] According to an example, performing a cell selection or cell reselection procedure based on information indicating use of an extended k-Mac by at least one cell comprises: determining that at least one cell uses extended k-Mac based on the information indicating use of an extended k-Mac by at least one cell; and　 in response to determining that at least one cell uses extended k-Mac, performing at least one of: not searching for the at least one cell using extended k-Mac, deprioritizing the at least one cell using extended k-Mac, and considering the at least one cell using extended k-Mac to be barred.

[0252] According to an example, the method further comprises determining whether a further condition is satisfied; and in response to determining that at least one cell uses extended k-Mac and that the further condition is satisfied, performing at least one of: not searching for the at least one cell using extended k-Mac, deprioritizing the at least one cell using extended k-Mac, and considering the at least one cell using extended k-Mac to be barred.

[0253] According to an example, performing a cell selection or cell reselection procedure based on information indicating use of an extended k-Mac by at least one cell comprises: determining that at least one cell uses an extended k-Mac value greater than a threshold based on the information indicating use of an extended k-Mac by at least one cell; and　 in response to determining that at least one cell uses extended k-Mac, performing at least one of: not searching for the at least one cell using an extended k-Mac value greater than the threshold, deprioritizing the at least one cell using an extended k-Mac value greater than the threshold, and considering the at least one cell using an extended k-Mac value greater than the threshold to be barred.

[0254] According to an example, the method further comprises determining whether a further condition is satisfied; and in response to determining that at least one cell uses extended k-Mac and that the further condition is satisfied, performing at least one of: not searching for the at least one cell using an extended k-Mac value greater than the threshold, deprioritizing the at least one cell using an extended k-Mac value greater than the threshold, and considering the at least one cell using an extended k-Mac value greater than the threshold to be barred.

[0255] According to an example, the further condition comprises at least one of: determining that at least one other cell does not use extended k-Mac, determining that at least one other cell does not use an extended k-Mac value greater than the threshold, determining that the first network entity is configured to perform a cell selection or cell reselection procedure based on information indicating use of an extended k-Mac; determining that a service or traffic of the first network entity is a predetermined type (e.g. delay intolerant type, voice type, emergency type).

[0256] According to an example, performing a cell selection or cell reselection procedure based on information indicating use of an extended k-Mac by at least one cell comprises: determining that at least one cell uses extended k-Mac; determining, if the first network entity does not support extended k-Mac, if the first network entity is barred from the cell using extended k-Mac based on existing cellBarred indications.

[0257] According to an example, the method further comprises determining, if the first network entity does support extended k-Mac, if the first network entity is barred from the cell using extended k-Mac based on an extended k-Mac cellBarred indication.

[0258] According to an example, the information indicating use of an extended k-Mac by at least one cell comprises at least one of: information indicating that the at least one cell is using extended k-Mac,　 information indicating that the cell operates in a multi-hop mode, and information indicating an extended k-Mac value used by the at least one cell.

[0259] According to an example, the information indicating an extended k-Mac value used by the at least one cell comprises at least one of: an absolute extended k-Mac value, an additive extended k-Mac value, a multiplicative extended k-Mac value.

[0260] According to an example, the method further comprises performing a random access procedure with a first cell based on the extended k-Mac value indicated by the information indicating the extended k-Mac value used by the first cell.

[0261] According to an example, the method further comprises determining if information indicating a k-Mac value is signalled for a first cell; determining if information indicating an extended k-Mac value is signalled for the first cell; using the signalled extended k-Mac value for the first cell in response to determining that information indicating a k-Mac value is not signalled for the first cell and that information indicating an extended k-Mac value is signalled for the first cell; using the signalled k-Mac value for the first cell in response to determining that information indicating a k-Mac value is signalled for the first cell and that information indicating an extended k-Mac value is not signalled for the first cell; and using a default k-Mac value for the first cell in response to determining that information indicating a k-Mac value is not signalled for the first cell and that information indicating an extended k-Mac value is not signalled for the first cell.

[0262] According to an example, the information indicating use of an extended k-Mac by at least one cell is received in at least one of: system information (e.g. SIB31, SIB31-NB, SIB1),　 ephemeris information,　 satellite assistance information, and neighbouring cell signalling (e.g. SIB32, SIB33).

[0263] According to an example, there is provided a method of a first network entity (e.g. a UE), the method comprising: transmitting, to a second network entity, at least one of: information indicating that the UE supports a specific frequency band, information indicating that the UE supports internet of things (IoT) non-terrestrial network (NTN) time division duplex (TDD), and information indicating capability of the first network entity to support extended k-Mac.

[0264] According to an example, there is provided a method of a second network entity (e.g. a base station), the method comprising: determining whether a first network entity (e.g. a UE) supports extended k-Mac; wherein determining whether the first network entity supports extended k-Mac comprises determining whether the first network entity supports extended k-Mac based on receiving, from the first network entity, at least one of: information indicating that the UE supports a specific frequency band, information indicating that the UE supports internet of things (IoT) non-terrestrial network (NTN) time division duplex (TDD), and information indicating capability of the first network entity to support extended k-Mac.

[0265] According to an example, there is provided a first network entity (e.g. a UE) configured to operate according to a method of any of the above-described examples.

[0266] According to an example, there is provided a second network entity (e.g. a base station) configured to operate according to a method of any of the above-described examples

[0267] According to an example, there is provided a network (e.g. a NTN, an IoT NTN, an A2G network) or wireless communication system comprising a first network entity according to any of the above-described examples and a second network entity according to any of the above-described examples.

[0268] According to an example, there is provided a computer program comprising instructions which, when the program　 is executed by a computer or processor, cause the computer or processor to carry out a method according to any one of the above-described examples.

[0269] According to an example, there is provided a computer or processor-readable data carrier having stored thereon a computer program comprising instructions which, when the program　 is executed by a computer or processor, cause the computer or processor to carry out a method according to any one of the above-described examples.

[0270] In a first example, there is provided a method of a first network entity (e.g. a UE) in a network (e.g. a NTN, an IoT NTN, an A2G network), the method comprising: obtaining information indicating use of an extended k-Mac by at least one cell.

[0271] In a second example, there is provided the method of the first example, further comprising performing a cell selection or cell reselection procedure based on the information indicating use of an extended k-Mac by the least one cell.

[0272] In a third example, there is provide the method of the second example, wherein performing a cell selection or cell reselection procedure based on information indicating use of an extended k-Mac by at least one cell comprises: determining that at least one cell uses extended k-Mac based on the information indicating use of an extended k-Mac by at least one cell; and　 in response to determining that at least one cell uses extended k-Mac, performing at least one of: not searching for the at least one cell using extended k-Mac, deprioritizing the at least one cell using extended k-Mac, and considering the at least one cell using extended k-Mac to be barred.

[0273] In a fourth example, there is provided the method of the third example, further comprising determining whether a further condition is satisfied; and in response to determining that at least one cell uses extended k-Mac and that the further condition is satisfied, performing at least one of: not searching for the at least one cell using extended k-Mac, deprioritizing the at least one cell using extended k-Mac, and considering the at least one cell using extended k-Mac to be barred.

[0274] In a fifth example, there is provided the method of the second example, wherein performing a cell selection or cell reselection procedure based on information indicating use of an extended k-Mac by at least one cell comprises: determining that at least one cell uses an extended k-Mac value greater than a threshold based on the information indicating use of an extended k-Mac by at least one cell; and　 in response to determining that at least one cell uses extended k-Mac, performing at least one of: not searching for the at least one cell using an extended k-Mac value greater than the threshold, deprioritizing the at least one cell using an extended k-Mac value greater than the threshold, and considering the at least one cell using an extended k-Mac value greater than the threshold to be barred.

[0275] In a sixth example, there is provided the method of the fifth example, further comprising determining whether a further condition is satisfied; and in response to determining that at least one cell uses extended k-Mac and that the further condition is satisfied, performing at least one of: not searching for the at least one cell using an extended k-Mac value greater than the threshold, deprioritizing the at least one cell using an extended k-Mac value greater than the threshold, and considering the at least one cell using an extended k-Mac value greater than the threshold to be barred.

[0276] In a seventh example, there is provided the method of the fourth or sixth example, wherein the further condition comprises at least one of: determining that at least one other cell does not use extended k-Mac, determining that at least one other cell does not use an extended k-Mac value greater than the threshold, determining that the first network entity is configured to perform a cell selection or cell reselection procedure based on information indicating use of an extended k-Mac; determining that a service or traffic of the first network entity is a predetermined type (e.g. delay intolerant type, voice type, emergency type).

[0277] In an eighth example, there is provided the method of the second example, wherein performing a cell selection or cell reselection procedure based on information indicating use of an extended k-Mac by at least one cell comprises: determining that at least one cell uses extended k-Mac; determining, if the first network entity does not support extended k-Mac, if the first network entity is barred from the cell using extended k-Mac based on existing cellBarred indications.

[0278] In a ninth example, there is provided the method of the eighth example, further comprising: determining, if the first network entity does support extended k-Mac, if the first network entity is barred from the cell using extended k-Mac based on an extended k-Mac cellBarred indication.

[0279] In a tenth example, there is provided the method of any of the first to ninth examples, wherein the information indicating use of an extended k-Mac by at least one cell comprises at least one of: information indicating that the at least one cell is using extended k-Mac,　 information indicating that the cell operates in a multi-hop mode, and information indicating an extended k-Mac value used by the at least one cell.

[0280] In an eleventh example, there is provided the method of the tenth example, wherein the information indicating an extended k-Mac value used by the at least one cell comprises at least one of: an absolute extended k-Mac value, an additive extended k-Mac value, a multiplicative extended k-Mac value.

[0281] In a twelfth example, there is provided the method of the tenth or eleventh example, further comprising: performing a random access procedure with a first cell based on the extended k-Mac value indicated by the information indicating the extended k-Mac value used by the first cell.

[0282] In a thirteenth example, there is provided the method of any of the first to twelfth examples, further comprising: determining if information indicating a k-Mac value is signalled for a first cell; determining if information indicating an extended k-Mac value is signalled for the first cell; using the signalled extended k-Mac value for the first cell in response to determining that information indicating a k-Mac value is not signalled for the first cell and that information indicating an extended k-Mac value is signalled for the first cell; using the signalled k-Mac value for the first cell in response to determining that information indicating a k-Mac value is signalled for the first cell and that information indicating an extended k-Mac value is not signalled for the first cell; and using a default k-Mac value for the first cell in response to determining that information indicating a k-Mac value is not signalled for the first cell and that information indicating an extended k-Mac value is not signalled for the first cell.

[0283] In a fourteenth example, there is provided the method of any of the first to thirteenth examples, wherein the information indicating use of an extended k-Mac by at least one cell is received in at least one of: system information (e.g. SIB31, SIB31-NB, SIB1),　 ephemeris information,　 satellite assistance information, and neighbouring cell signalling (e.g. SIB32, SIB33).

[0284] In a fifteenth example, there is provided a method of a first network entity (e.g. a UE), the method comprising: transmitting, to a second network entity, at least one of: information indicating that the UE supports a specific frequency band, information indicating that the UE supports internet of things (IoT) non-terrestrial network (NTN) time division duplex (TDD), and information indicating capability of the first network entity to support extended k-Mac.

[0285] In a sixteenth example, there is provided a method of a second network entity (e.g. a base station), the method comprising: determining whether a first network entity (e.g. a UE) supports extended k-Mac; wherein determining whether the first network entity supports extended k-Mac comprises determining whether the first network entity supports extended k-Mac based on receiving, from the first network entity, at least one of: information indicating that the UE supports a specific frequency band, information indicating that the UE supports internet of things (IoT) non-terrestrial network (NTN) time division duplex (TDD), and information indicating capability of the first network entity to support extended k-Mac.

[0286] In a seventeenth example, there is provided a first network entity (e.g. a UE) configured to operate according to a method of any of the first to fifteenth examples.

[0287] In an eighteenth example, there is provided a second network entity (e.g. a base station) configured to operate according to a method of the sixteenth example.

[0288] In a nineteenth example, there is provided a network (e.g. a NTN, an IoT NTN, an A2G network) or wireless communication system comprising a first network entity according to the seventeenth example and a second network entity according to the eighteenth example.

[0289] In a twentieth example, there is provided a computer program comprising instructions which, when the program　 is executed by a computer or processor, cause the computer or processor to carry out a method according to any one of the first to sixteenth examples.

[0290] In a twenty-first example, there is provided a computer or processor-readable data carrier having stored thereon a computer program according to　the twentieth example.

[0291] In a first instance, there is provided a method of a first network entity (e.g. a UE) in a network (e.g. a NTN, an IoT NTN, an A2G network), the method comprising: obtaining information indicating use of an extended k-Mac by at least one cell; wherein the information indicating use of an extended k-Mac by at least one cell is received in at least one of: system information (e.g. SIB31, SIB31-NB, SIB1), ephemeris information, satellite assistance information, and neighbouring cell signalling (e.g. SIB32, SIB33).

[0292] In a second instance, there is provided the method of the first instance, wherein the information indicating use of an extended k-Mac by at least one cell comprises at least one of: information indicating that the at least one cell is using extended k-Mac, information indicating that the cell operates in a multi-hop mode, and information indicating an extended k-Mac value used by the at least one cell.

[0293] In a third instance, there is provided the method of the second instance, wherein the information indicating an extended k-Mac value used by the at least one cell comprises at least one of: an absolute extended k-Mac value, an additive extended k-Mac value, a multiplicative extended k-Mac value.

[0294] In a fourth instance, there is provided the method of any one of the first to third instances, wherein the method further comprises: determining that at least one cell uses extended k-Mac; determining, if the first network entity supports extended k-Mac, if the first network entity is barred from the at least one cell based on a cellBarred indication only applicable to network entities supporting extended k-Mac.

[0295] In a fifth instance, there is provided the method of the fourth instance, wherein the cellBarred indication only applicable to network entities supporting extended k-Mac is received in system information (e.g. SIB1).

[0296] In a sixth instance, there is provided the method of any one of the first to fifth instances, wherein the method further comprises performing a cell selection or cell reselection procedure based on the information indicating use of an extended k-Mac by the least one cell.

[0297] In a seventh instance, there is provided the method of the sixth instance, wherein performing a cell selection or cell reselection procedure based on information indicating use of an extended k-Mac by at least one cell comprises: determining that at least one cell uses extended k-Mac; determining, if the first network entity does not support extended k-Mac, if the first network entity is barred from the cell using extended k-Mac based on existing cellBarred indications.

[0298] In an eighth instance, there is provided the method of any one of the fourth to seventh instances, wherein performing a cell selection or cell reselection procedure based on information indicating use of an extended k-Mac by at least one cell comprises: determining that at least one cell uses extended k-Mac based on the information indicating use of an extended k-Mac by at least one cell; and in response to determining that at least one cell uses extended k-Mac, performing at least one of: not searching for the at least one cell using extended k-Mac, deprioritizing the at least one cell using extended k-Mac, and considering the at least one cell using extended k-Mac to be barred.

[0299] In a ninth instance, there is provided the method of the eighth instance, wherein, the method further comprises determining whether a further condition is satisfied; and in response to determining that at least one cell uses extended k-Mac and that the further condition is satisfied, performing at least one of: not searching for the at least one cell using extended k-Mac, deprioritizing the at least one cell using extended k-Mac, and considering the at least one cell using extended k-Mac to be barred.

[0300] In a tenth instance, there is provided the method of the fourth instance, wherein performing a cell selection or cell reselection procedure based on information indicating use of an extended k-Mac by at least one cell comprises: determining that at least one cell uses an extended k-Mac value greater than a threshold based on the information indicating use of an extended k-Mac by at least one cell; and in response to determining that at least one cell uses extended k-Mac, performing at least one of: not searching for the at least one cell using an extended k-Mac value greater than the threshold, deprioritizing the at least one cell using an extended k-Mac value greater than the threshold, and considering the at least one cell using an extended k-Mac value greater than the threshold to be barred.

[0301] In an eleventh instance, there is provided the method of the tenth instance, wherein the method further comprises determining whether a further condition is satisfied; and in response to determining that at least one cell uses extended k-Mac and that the further condition is satisfied, performing at least one of: not searching for the at least one cell using an extended k-Mac value greater than the threshold, deprioritizing the at least one cell using an extended k-Mac value greater than the threshold, and considering the at least one cell using an extended k-Mac value greater than the threshold to be barred.

[0302] In a twelfth instance, there is provided the method of the ninth or eleventh instance, wherein the further condition comprises at least one of: determining that at least one other cell does not use extended k-Mac, determining that at least one other cell does not use an extended k-Mac value greater than the threshold, determining that the first network entity is configured to perform a cell selection or cell reselection procedure based on information indicating use of an extended k-Mac; determining that a service or traffic of the first network entity is a predetermined type (e.g. delay intolerant type, voice type, emergency type).

[0303] In a thirteenth instance, there is provided the method of the second or third instance, wherein the method further comprises performing a random access procedure with a first cell based on the extended k-Mac value indicated by the information indicating the extended k-Mac value used by the first cell.

[0304] In a fourteenth instance, there is provided the method of any one of the first to thirteenth instances, wherein the method further comprises determining if information indicating a k-Mac value is signalled for a first cell; determining if information indicating an extended k-Mac value is signalled for the first cell; using the signalled extended k-Mac value for the first cell in response to determining that information indicating a k-Mac value is not signalled for the first cell and that information indicating an extended k-Mac value is signalled for the first cell; using the signalled k-Mac value for the first cell in response to determining that information indicating a k-Mac value is signalled for the first cell and that information indicating an extended k-Mac value is not signalled for the first cell; and using a default k-Mac value for the first cell in response to determining that information indicating a k-Mac value is not signalled for the first cell and that information indicating an extended k-Mac value is not signalled for the first cell.

[0305] In a fifteenth instance, there is provided a method of a second network entity (e.g. a base station) in a network (e.g. a NTN, an IoT NTN, an A2G network), the method comprising: transmitting, to a first network entity (e.g. a UE) information indicating use of an extended k-Mac by at least one cell; wherein the information indicating use of an extended k-Mac by at least one cell is transmitted in at least one of: system information (e.g. SIB31, SIB31-NB, SIB1), ephemeris information, satellite assistance information, and neighbouring cell signalling (e.g. SIB32, SIB33).

[0306] In a sixteenth instance, there is provided the method of the fifteenth instance, wherein the method further comprises determining that the at least one cell applies extended k-Mac; and transmitting, in response to determining that the at least one cell applies extended k-Mac, the information indicating use of the extended k-Mac by the at least one cell.

[0307] In a seventeenth instance, there is provided the method of the sixteenth instance, wherein the information indicating use of the extended k-Mac by the at least one cell is transmitted in system information; and wherein transmitting, in response to determining that the at least one cell applies extended k-Mac, the information indicating use of the extended k-Mac by the at least one cell comprises initiating a system information update procedure in response to determining that the at least one cell applies extended k-Mac.

[0308] In an eighteenth instance, there is provided a method of a first network entity (e.g. a UE), the method comprising: transmitting, to a second network entity, at least one of: information indicating that the first network entity supports a specific frequency band, wherein an indication that the first network entity supports a specific frequency band means that the first network entity supports extended k-Mac, information indicating that the first network entity supports internet of things (IoT) non-terrestrial network (NTN) time division duplex (TDD), and information indicating capability of the first network entity to support extended k-Mac.

[0309] In a nineteenth instance, there is provided a method of a second network entity (e.g. a base station), the method comprising: determining whether a first network entity (e.g. a UE) supports extended k-Mac; wherein determining whether the first network entity supports extended k-Mac comprises determining that the first network entity supports extended k-Mac based on receiving, from the first network entity, at least one of: information indicating that the first network entity supports a specific frequency band, information indicating that the first network entity supports internet of things (IoT) non-terrestrial network (NTN) time division duplex (TDD), and information indicating capability of the first network entity to support extended k-Mac.

[0310] In a twentieth instance, there is provided a first network entity (e.g. a UE) configured to operate according to a method of any one of the first to fourteenth or eighteenth examples.

[0311] In a twenty-first instance, there is provided a second network entity (e.g. a base station) configured to operate according to a method of any one of the fifteenth to seventeenth or nineteenth examples.

[0312] In a twenty-second instance, there is provided a network (e.g. a NTN, an IoT NTN, an A2G network) or wireless communication system comprising a first network entity according to the twentieth instance and a second network entity according to the twenty-first instance.

[0313] In a twenty-third instance, there is provided a computer program comprising instructions which, when the program is executed by a computer or processor, cause the computer or processor to carry out a method according to any one of the first to nineteenth instances.

[0314] In a twenty-fourth instance, there is provided a computer or processor-readable data carrier having stored thereon a computer program according to the twenty-third instance.

[0315] While the invention has been shown 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 invention.

[0316] Certain examples of the present disclosure provide one or more techniques as disclosed in the appended annex to the description. The skilled person will appreciate that any of these techniques may be applied in combination with any of the techniques described above and illustrated in the Figures.

[0317] ANNEX

[0318] By way of further explanation, examples of how the existing 3GPP standards might be modified in view of certain aspects of the present disclosure are provided.

[0319] Example #1

[0320] Changes indicated in underlined bold type for LTE and NR specifications:

[0321] -------------------------- Example based on 36.331 V18.4.0 --------------------------

[0322] - SystemInformationBlockType1-NB

[0323] TheSystemInformationBlockType1-NBmessagecontains information relevant when evaluating if a UE is allowed to access a cell and defines the scheduling of other system information.

[0324] Signalling radio bearer: N / A

[0325] RLC-SAP: TM

[0326] Logical channel: BCCH

[0327] Direction: E-UTRAN to UE

[0328] SystemInformationBlockType1-NB message

[0329]

[0330]

[0331] -------------------------- Example based on 36.331 V18.4.0 --------------------------

[0332]

[0333] -------------------------- Example based on 38.331 V18.4.0 --------------------------

[0334] SIB1 message

[0335]

[0336]

[0337]

[0338] -------------------------- Example based on 38.331 V18.4.0 --------------------------

[0339]

[0340] Example #2

[0341] Changes indicated in underlined bold type for LTE specifications:

[0342]

[0343] -------------------------- Example based on 36.331 V18.4.0 --------------------------

[0344] - SystemInformationBlockType31

[0345] The IESystemInformationBlockType31contains satellite assistance information for the serving cell.SystemInformationBlockType31is only signalled for an NTN cell.

[0346] SystemInformationBlockType31 information element

[0347]

[0348]

[0349]

[0350] -SystemInformationBlockType31-NB

[0351] The IESystemInformationBlockType31-NBcontains satellite assistance information.SystemInformationBlockType31-NBis only signalled in a NTN cell.

[0352] SystemInformationBlockType31-NB information element

[0353]

[0354]

[0355] -------------------------- Example based on 36.331 V18.4.0 --------------------------

[0356]

[0357]

[0358] Example #3

[0359] Changes indicated in underlined bold type for LTE specifications:

[0360] -------------------------- Example based on 36.306 V18.4.0 --------------------------

[0361] 7 Conditionally Mandatory features

[0362] ...

[0363] 7.10 Other features

[0364] ...

[0365] 7.10.XExtended K-Mac

[0366] It is mandatory to support extended k-Mac for UEs that indicate support of IoT NTN TDD band(s), see TS 36.102.

[0367] -------------------------- Example based on 36.306 V18.4.0 --------------------------

[0368]

[0369] Example #4

[0370] Changes indicated in underlined bold type for LTE specifications:

[0371]

[0372] -------------------------- Example based on 36.331 V18.4.0 --------------------------

[0373] - SystemInformationBlockType33

[0374] The IESystemInformationBlockType33contains satellite assistance information for neighbour cells.

[0375] SystemInformationBlockType33 information element

[0376]

[0377]

[0378] - SystemInformationBlockType33-NB

[0379] The IESystemInformationBlockType33-NBcontains satellite assistance information for neighbour cells.

[0380] SystemInformationBlockType33-NB information element

[0381]

[0382] -------------------------- Example based on 36.331 V18.4.0 --------------------------

Claims

1.A method of a user equipment (UE) in a network, the method comprising:transmitting, to a base station (BS), capability information related to supported bands;receiving, from the BS, satellite assistance information for neighbour cells, wherein the satellite assistance information for neighbor cells includes information for extended k-Mac,wherein in case that a specific band is supported based on the capability information related to supported bands, the extended k-Mac is supported,wherein the extended k-Mac is a scheduling offset that is used if uplink and downlink timing is not aligned,wherein a maximum value of the extended k-Mac is larger than 512.2.The method of claim 1,wherein the satellite assistance information is included in system information block (SIB) 33-NB.3.The method of claim 1, wherein the maximum value of the extended k-Mac is 1024.4.The method of claim 1, further comprising:receiving, from the BS, cell barring related information associated with non-terrestrial network (NTN),determining whether the cell is barred based on the cell barring related information associated with NTN, in case that the extended k-Mac is supported.5.A method of a base station (BS) in a network, the method comprising:receiving, from a user equipment (UE), capability information related to supported bands;transmitting, to the UE, satellite assistance information for neighbour cells, wherein the satellite assistance information for neighbor cells includes information for extended k-Mac,wherein in case that a specific band is supported based on the capability information related to supported bands, the extended k-Mac is supported,wherein the extended k-Mac is a scheduling offset that is used if uplink and downlink timing is not aligned,wherein a maximum value of the extended k-Mac is larger than 512.6.The method of claim 5,wherein the satellite assistance information is included in system information block (SIB) 33-NB.7.The method of claim 5, wherein the maximum value of the extended k-Mac is 1024.8.The method of claim 5, further comprising:transmitting, to the UE, cell barring related information associated with non-terrestrial network (NTN),wherein whether the cell is barred is determined based on the cell barring related information associated with NTN, in case that the extended k-Mac is supported.9.A user equipment (UE) in a network, comprising:a transceiver; anda controller coupled to the transceiver and configured to:transmit, to a base station (BS), capability information related to supported bands,receive, from the BS, satellite assistance information for neighbour cells, wherein the satellite assistance information for neighbor cells includes information for extended k-Mac,wherein in case that a specific band is supported based on the capability information related to supported bands, the extended k-Mac is supported,wherein the extended k-Mac is a scheduling offset that is used if uplink and downlink timing is not aligned,wherein a maximum value of the extended k-Mac is larger than 512.10.The UE of claim 9,wherein the satellite assistance information is included in system information block (SIB) 33-NB.11.The UE of claim 9, wherein the maximum value of the extended k-Mac is 1024.12.The UE of claim 9, wherein the controller is further configured to:receive, from the BS, cell barring related information associated with non-terrestrial network (NTN),determine whether the cell is barred based on the cell barring related information associated with NTN, in case that the extended k-Mac is supported.13.A base station (BS) in a network, comprising:a transceiver; anda controller coupled to the transceiver and configured to:receive, from a user equipment (UE), capability information related to supported bands,transmit, to the UE, satellite assistance information for neighbour cells, wherein the satellite assistance information for neighbor cells includes information for extended k-Mac,wherein in case that a specific band is supported based on the capability information related to supported bands, the extended k-Mac is supported,wherein the extended k-Mac is a scheduling offset that is used if uplink and downlink timing is not aligned,wherein a maximum value of the extended k-Mac is larger than 512.14.The BS of claim 13,wherein the satellite assistance information is included in system information block (SIB) 33-NB.15.The BS of claim 13, wherein the maximum value of the extended k-Mac is 1024.

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