Terminal device cooperation for receiving signal

Abstract

The present disclosure relates to the field of telecommunication and in particular to methods, apparatuses and computer readable storage media for the cooperation between the terminal devices to receive signal, such as a signal, on-demand signal, and on- demand system information block For example, one of the embodiments provides an apparatus comprising at least one processor, and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to perform: transmitting, to a second user device, a request message requesting an assistance to access a cell which is in an on-demand signal mode; receiving, from the second user device, a response message comprising assistance information; and receiving, from the cell which is in a broadcast mode, a signal based on the assistance information.

Description

TERMINAL DEVICE COOPERATION FOR RECEIVING SIGNALFIELD

[0001] Embodiments of the present disclosure relate to the field of telecommunication and in particular to methods, apparatuses, and computer readable storage media for the cooperation between the terminal devices to receive signal, such as signal, on-demand signal, and on-demand system information block.BACKGROUND

[0002] In the 3GPP (3rd Generation Partnership Project) cellular network, a network energy saving (NES) is important for optimizing energy consumption in the cellular network.

[0003] The radio access network (RAN) accounts for majority of the energy consumed by a typical mobile telecommunications system, and radio units are the most significant factor in total power consumption. RAN energy consumption includes Node B, eNodeB and gNodeB energy usage as well as the energy used by associated infrastructure, such as air conditioning, inverters and rectifiers. It also includes the energy used by repeaters and all energy consumption associated with backhaul transport.SUMMARY

[0004] The scope of protection sought for various example embodiments is set out by the claims. According to some aspects, there is provided the subject matter of the independent claims. Some further aspects are defined in the dependent claims. The example embodiments and features, if any, described in this specification that do not fall under the scope of the claims are to be interpreted as examples useful for understanding various embodiments.

[0005] Other features and advantages of the embodiments of the present disclosure will also be apparent from the following description of specific embodiments when read in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of embodiments of the disclosure.BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Embodiments of the disclosure are presented in the sense of examples and their advantages are explained in greater detail below, with reference to the accompanying drawings.

[0007] FIG. 1 illustrates an example of a wireless communication network.

[0008] FIG. 2 is a schematic diagram illustrating deployments of cells including the NES cell in which example embodiments of the present disclosure may be implemented.

[0009] FIG. 3 is a schematic flow diagram for explaining various methods according to the first aspect of the disclosure.

[0010] FIG. 4 is a schematic flow diagram illustrating example embodiments according to the first aspect of the disclosure.

[0011] FIG. 5 illustrates one of embodiments according to the first aspect of the disclosure.

[0012] FIG. 6 is a schematic flow diagram for explaining various methods according to the second aspect of the disclosure.

[0013] FIG. 7 is a schematic flow diagram illustrating example embodiments according to the second aspect of the disclosure.

[0014] FIG. 8 illustrates the first embodiment according to the second aspect of the disclosure.

[0015] FIG. 9 illustrates the second embodiment according to the second aspect of the disclosure.

[0016] FIG. 10 illustrates an example of an apparatus.

[0017] FIG. 11 illustrates an example of an apparatus.

[0018] Throughout the drawings, the same or similar reference numerals may represent the same or similar element.DETAILED DESCRIPTION

[0019] The following embodiments are exemplifying. Principle of the present disclosure will now be described with reference to some example embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitation as to the scope of the disclosure. Embodiments described herein may be implemented in various manners other than the ones described below.

[0020] In the following description and claims, unless defined otherwise, all technical and scientific terms used herein may have the same meaning as commonly understood by one of ordinary skills in the art to which this disclosure belongs.

[0021] References in the present disclosure to "one embodiment," "an embodiment," "an example embodiment," and the like indicate that the embodiment described may include a particular feature, structure, element or characteristic, but it is not necessary that every embodiment includes the particular feature, structure, element or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with anembodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, element or characteristic in connection with other embodiments whether or not explicitly described.

[0022] It shall be understood that although the terms "first," "second" and the like may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and similarly, a second element could be termed a first element, without departing from the scope of example embodiments. As used herein, the term "and / or" includes any and all combinations of one or more of the listed terms.

[0023] As used herein, "at least one of the following: " and "at least one of " and similar wording, where the list of two or more elements are joined by "and" or "or", mean at least any one of the elements, or at least any two or more of the elements, or at least all the elements.

[0024] As used herein, unless stated explicitly, performing a step "in response to A" does not indicate that the step is performed immediately after "A" occurs and one or more intervening steps may be included.

[0025] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises", "comprising", "has", "having", "includes" and / or "including", when used herein, specify the presence of stated features, elements, and / or components etc., but do not preclude the presence or addition of one or more other features, elements, components and / or combinations thereof.

[0026] As used in this application, the term "circuitry" may refer to one or more or all of the following:(a) hardware-only circuit implementations (such as implementations in only analog and / or digital circuitry) and(b) combinations of hardware circuits and software, such as (as applicable):(i) a combination of analog and / or digital hardware circuit(s) with software / firmware and(ii) any portions of hardware processor(s) with software (including digital signal processor(s)), software, and memory(ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) and(c) hardware circuit(s) and or processor(s), such as a microprocessor(s) or a portion of a microprocessor(s), that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation.

[0027] This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and / or firmware. The term circuitry also covers, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit fora mobile device or a similar integrated circuit in server, a cellular network device, or other computing or network device.

[0028] As used herein, the term "communication network" refers to a network following any suitable communication standards, such as New Radio (NR), Long Term Evolution (LTE), LTE-Advanced (LTE-A), Wideband Code Division Multiple Access (WCDMA), High-Speed Packet Access (HSPA), Narrow Band Internet of Things (NB-loT) and so on. Furthermore, the communications between a terminal device and a network device in the communication network may be performed according to any suitable generation communication protocols, including, but not limited to, the first generation (1G), the second generation (2G), 2.5G, 2.75G, the third generation (3G), the fourth generation (4G), 4.5G, the fifth generation (5G), the sixth generation (6G) communication protocols, and / or any other protocols either currently known or to be developed in the future. Embodiments of the present disclosure may be applied in various communication systems. Given the rapid development in communications, there will of course also be future type communication technologies and systems with which the present disclosure may be embodied. It should not be seen as limiting the scope of the present disclosure to only the aforementioned system.

[0029] As used herein, the term "network device" refers to a node in a communication network via which a user device accesses the network and receives services therefrom. The network device may refer to a network entity, a base station (BS) or an access point (AP), for example, a node B (NodeB or NB), an evolved NodeB (eNodeB or eNB), an NR NB (also referred to as a gNB), a radio access network (RAN) node, a new generation RAN (NG-RAN) node, a Remote Radio Unit (RRU), a radio header (RH), a remote radio head (RRH), a relay, an Integrated Access and Backhaul (IAB) node, a low power node such as a femto, a pico, a non-terrestrial network (NTN) device or non-ground network device such as a satellite network device, a low earth orbit (LEO) satellite and a geosynchronous earth orbit (GEO) satellite, an aircraft network device, and so forth, depending on the applied terminology and technology. In some example embodiments, radio access network (RAN) split architecture includes a Centralized Unit (CU) and a Distributed Unit (DU) at an IAB donor node. An IAB node includes a Mobile Terminal (IAB-MT) part that behaves like a UE toward the parent node, and a DU part of an IAB node behaves like a base station toward the nexthop IAB node.

[0030] The term "user device" refers to any end device that may be capable of wireless communication. By way of example rather than limitation, the user device may also be referred to as a communication device, user equipment (UE), a Subscriber Station (SS), aPortable Subscriber Station, a Mobile Station (MS), a terminal device or an Access Terminal (AT). The user device may include, but not limited to, a mobile phone, a cellular phone, a smart phone, voice over IP (VoIP) phones, wireless local loop phones, a tablet, a wearable terminal device, a personal digital assistant (PDA), portable computers, desktop computer, image capture terminal devices such as digital cameras, gaming terminal devices, music storage and playback appliances, vehicle-mounted wireless terminal devices, wireless endpoints, mobile stations, laptop-embedded equipment (LEE), laptop-mounted equipment (LME), USB dongles, smart devices, wireless customer-premises equipment (CPE), an Internet of Things (loT) device, a watch or other wearable, a head-mounted display (HMD), a vehicle, a drone, a medical device and applications (e.g., remote surgery), an industrial device and applications (e.g., a robot and / or other wireless devices operating in an industrial and / or an automated processing chain contexts), a consumer electronics device, a device operating on commercial and / or industrial wireless networks, and the like. The user device may also correspond to a Mobile Termination (MT) part of an IAB node (e.g., a relay node). In the following description, the terms "user device", "communication device", "terminal", "terminal device", "user equipment" and "UE" may be used interchangeably.

[0031] As used herein, the term "resource," "transmission resource," "resource block," "physical resource block" (PRB), "uplink resource," "downlink resource", "sidelink resource", "channel" may refer to any resource for performing a communication, for example, a communication between a user device and a network entity, such as a resource in time domain, a resource in frequency domain, a resource in space domain, a resource in code domain, or any other resource enabling a communication, and the like. In the following, unless explicitly stated, a resource in both frequency domain and time domain will be used as an example of a transmission resource for describing some example embodiments of the present disclosure. It is noted that example embodiments of the present disclosure are equally applicable to other resources in other domains.

[0032] FIG. 1 depicts an example of a simplified wireless communication network showing some physical and logical network entities. The connections shown in FIG. 1 may be physical connections or logical connections. It is apparent to a person skilled in the art that the wireless communication network may also comprise other physical and logical entities than those shown in FIG. 1.

[0033] The example embodiments described herein are not, however, restricted to the wireless communication network given as an example but a person skilled in the art may apply the embodiments described herein to other wireless communication networks provided with necessary properties.

[0034] The example wireless communication network shown in FIG. 1 includes an access network, such as a radio access network (RAN), and a core network 110.

[0035] FIG. 1 shows user equipment (UE) 100, 102 configured to be in a wireless connection on one or more communication channels in a radio cell with an access node (AN)104 of an access network. The AN 104 may be an evolved NodeB (abbreviated as eNB or eNodeB), or a next generation evolved NodeB (abbreviated as ng-eNB), or a next generation NodeB (abbreviated as gNB or gNodeB), providing the radio cell. The wireless connection (e.g., radio link) from a UE to the access node 104 may be called uplink (UL) or reverse link, and the wireless connection (e.g., radio link) from the access node to the UE may be called downlink (DL) or forward link. UE 100 may also communicate directly with UE 102, and vice versa, via a wireless connection generally referred to as a sidelink (SL). It should be appreciated that the access node 104 or its functionalities may be implemented by using any node, host, server or access point etc. entity suitable for providing such functionalities.

[0036] The access network may comprise more than one access node, in which case the access nodes may also be configured to communicate with one another over links, wired or wireless. These links between access nodes may be used for sending and receiving control plane signaling and also for routing data from one access node to another access node.

[0037] The access node may comprise a computing device configured to control the radio resources of the access node. The access node may also be referred to as a network entity, a base station, a base transceiver station (BTS), an access point, a cell site, a radio access node or any other type of node capable of being in a wireless connection with a UE (e.g., UEs 100, 102). The access node may include or be coupled to transceivers. From the transceivers of the access node, a connection may be provided to an antenna unit that establishes bi-directional radio links to UEs 100, 102. The antenna unit may comprise an antenna or antenna element, or a plurality of antennas or antenna elements.

[0038] The access node 104 may further be connected to a core network (CN) 110. The core network 110 may comprise an evolved packet core (EPC) network and / or a 5th generation core network (5GC). The EPC may comprise network entities, such as a serving gateway (S-GW for routing and forwarding data packets), a packet data network gateway (P- GW) for providing connectivity of UEs to external packet data networks, and a mobility management entity (MME). The 5GC may comprise network functions, such as a user plane function (UPF), an access and mobility management function (AMF), and a location management function (LMF).

[0039] The core network 110 may also be able to communicate with one or more external networks 113, such as a public switched telephone network or the Internet, or utilize services provided by them. For example, in 5G wireless communication networks, the UPF of the core network 110 may be configured to communicate with an external data network via an N6 interface. In LTE wireless communication networks, the P-GW of the core network 110 may be configured to communicate with an external data network.

[0040] The illustrated UE 100, 102 is one type of an apparatus to which resources on the air interface may be allocated and assigned. The UE 100, 102 may also be called a wireless communication device, a subscriber unit, a mobile station, a remote terminal, an access terminal, a user terminal, a terminal device, or a user device just to mention but a few names.The UE may be a computing device operating with or without a subscriber identification module (SIM), including, but not limited to, the following types of computing devices: a mobile phone, a smartphone, a personal digital assistant (PDA), a handset, a computing device comprising a wireless modem (e.g., an alarm or measurement device, etc.), a laptop computer, a desktop computer, a tablet, a game console, a notebook, a multimedia device, a reduced capability (RedCap) device, a wearable device (e.g., a watch, earphones or eyeglasses) with radio parts, a sensor comprising a wireless modem, or any computing device comprising a wireless modem integrated in a vehicle.

[0041] It should be appreciated that a UE may also be a nearly exclusive uplink-only device, of which an example may be a camera or video camera loading images or video clips to a network. A UE may also be a device having capability to operate in an Internet of Things (loT) network, which is a scenario in which objects may be provided with the ability to transfer data over a network without requiring human-to-human or human-to-computer interaction. The UE may also utilize cloud. In some applications, the computation may be carried out in the cloud or in another UE.

[0042] The wireless communication network may also be able to support the usage of cloud services, for example at least part of core network operations may be carried out as a cloud service (this is depicted in FIG. 1 by "cloud" 114). The wireless communication network may also comprise a central control entity, or the like, providing facilities for wireless communication networks of different operators to cooperate for example in spectrum sharing.

[0043] 5G enables using multiple input - multiple output (MIMO) antennas in the access node 104 and / or the UE 100, 102, many more base stations or access nodes than an LTE network (a so-called small cell concept), including macro sites operating in co-operation with smaller stations and employing a variety of radio technologies depending on service needs, use cases and / or spectrum available. 5G wireless communication networks may support a wide range of use cases and related applications including video streaming, augmented reality, different ways of data sharing and various forms of machine type applications, such as (massive) machine-type communications (mMTC), including vehicular safety, different sensors and real-time control.

[0044] In 5G wireless communication networks, access nodes and / or UEs may have multiple radio interfaces, namely below 6GHz, cmWave and mmWave, and also being integrable with existing legacy radio access technologies, such as the LTE. Integration with the LTE may be implemented, for example, as a system, where macro coverage may be provided by the LTE, and 5G radio interface access may come from small cells by aggregation to the LTE. In other words, a 5G wireless communication network may support both inter- RAT operability (such as LTE-5G) and inter-RI operability (inter-radio interface operability, such as below 6GHz - cmWave - mmWave). One of the concepts considered to be used in 5G wireless communication networks may be network slicing, in which multiple independent and dedicated virtual sub-networks (network instances) may be created withinthe substantially same infrastructure to run services that have different requirements on latency, reliability, throughput and mobility.

[0045] In some example embodiments, an access node (e.g., access node 104) may comprise: a radio unit (RU) comprising a radio transceiver (TRX), i.e., a transmitter (Tx) and a receiver (Rx); one or more distributed units (DUs) 105 that may be used for the so-called Layer 1 (LI) processing and real-time Layer 2 (L2) processing; and a central unit (CU) 108 (also known as a centralized unit) that may be used for non-real-time L2 and Layer 3 (L3) processing. The CU 108 may be connected to the one or more DUs 105 for example via an Fl interface. Such an embodiment of the access node may enable the centralization of CUs relative to the cell sites and DUs, whereas DUs may be more distributed and may even remain at cell sites. The CU and DU together may also be referred to as baseband or a baseband unit (BBU). The CU and DU may also be comprised in a radio access point (RAP).

[0046] The CU 108 may be a logical node hosting radio resource control (RRC), service data adaptation protocol (SDAP) and / or packet data convergence protocol (PDCP), of the NR protocol stack for an access node. The DU 105 may be a logical node hosting radio link control (RLC), medium access control (MAC) and / or physical (PHY) layers of the NR protocol stack for the access node. The operations of the DU may be at least partly controlled by the CU. It should also be understood that the distribution of functions between DU 105 and CU 108 may vary depending on implementation. The CU may comprise a control plane (CU-CP), which may be a logical node hosting the RRC and the control plane part of the PDCP protocol of the NR protocol stack for the access node. The CU may further comprise a user plane (CU-UP), which may be a logical node hosting the user plane part of the PDCP protocol and the SDAP protocol of the CU for the access node.

[0047] Cloud computing systems may also be used to provide the CU 108 and / or DU 105. A CU provided by a cloud computing system may be referred to as a virtualized CU (vCU). In addition to the vCU, there may also be a virtualized DU (vDU) provided by a cloud computing system. Furthermore, there may also be a combination, where the DU may be implemented on so-called bare metal solutions, for example application-specific integrated circuit (ASIC) or customer-specific standard product (CSSP) system-on-a-chip (SoC).

[0048] Edge cloud may be brought into the access network (e.g., RAN) by utilizing network function virtualization (NFV) and software defined networking (SDN). Using edge cloud may mean access node operations to be carried out, at least partly, in a computing system operationally coupled to a remote radio head (RRH) or a radio unit (RU) of an access node. It is also possible that access node operations may be performed on a distributed computing system or a cloud computing system located at the access node. Application of cloud RAN architecture enables RAN real-time functions being carried out at the access network (e.g., in a DU 105) and non-real-time functions being carried out in a centralized manner (e.g., in a CU 108).

[0049] It should also be understood that the distribution of functions between corenetwork operations and access node operations may differ in future wireless communication networks compared to that of the LTE or 5G, 6G, or even be non-existent. Some other technology advancements that may be used include big data and all-IP, which may change the way wireless communication networks are being constructed and managed. 5G (or new radio, NR) wireless communication networks may support multiple hierarchies, where multi-access edge computing (MEC) servers may be placed between the core network 110 and the access node 104. It should be appreciated that MEC may be applied in LTE wireless communication networks as well.

[0050] A 5G wireless communication network ("5G network") may also comprise a nonterrestrial communication network, such as a satellite communication network, to enhance or complement the coverage of the 5G radio access network. For example, satellite communication may support the transfer of data between the 5G radio access network and the core network, enabling more extensive network coverage. Possible use cases may be providing service continuity for machine-to-machine (M2M) or Internet of Things (loT) devices or for passengers on board of vehicles, or ensuring service availability for critical communications, and future railway / maritime / aeronautical communications. Satellite communication may utilize geostationary earth orbit (GEO) satellite systems, but also low earth orbit (LEO) satellite systems, in particular mega-constellations (systems in which hundreds of (nano)satellites are deployed). A given satellite 106 in the mega-constellation may cover several satellite-enabled network entities that create on-ground cells. The on- ground cells may be created through an on-ground relay access node or by an access node 104 located on-ground or in a satellite.

[0051] It is obvious for a person skilled in the art that the access node 104 depicted in FIG. 1A is just an example of a part of an access network (e.g., a radio access network) and in practice, the access network may comprise a plurality of access nodes, the UEs 100, 102 may have access to a plurality of radio cells, and the access network may also comprise other apparatuses, such as physical layer relay access nodes or other entities. At least one of the access nodes may be a Home eNodeB or a Home gNodeB. A Home gNodeB or a Home eNodeB is a type of access node that may be used to provide indoor coverage inside a home, office, or other indoor environment.

[0052] Additionally, in a geographical area of an access network (e.g., a radio access network), a plurality of different kinds of radio cells as well as a plurality of radio cells may be provided. Radio cells may be macro cells (or umbrella cells) which may be large cells having a diameter of up to tens of kilometers, or smaller cells such as micro-, femto- or picocells. The access node(s) of FIG. 1A may provide any kind of these cells. A cellular radio network may be implemented as a multilayer access networks including several kinds of radio cells. In multilayer access networks, one access node may provide one kind of a radio cell or radio cells, and thus a plurality of access nodes may be needed to provide such a multilayer access network.

[0053] For fulfilling the need for improving performance of access networks, the conceptof "plug-and-play" access nodes may be introduced. An access network which may be able to use "plug-and-play" access nodes, may include, in addition to Home eNodeBs or Home gNodeBs, a Home Node B gateway, or HNB-GW (not shown in FIG. 1A). An HNB-GW, which may be installed within an operator's access network, may aggregate traffic from a large number of Home eNodeBs or Home gNodeBs back to a core network of the operator.

[0054] 1. Sidelink communication

[0055] The UE may support sidelink communication in all RRC states (see, TS 38.331). Note that when the UE undergoes the state transitions i.e., from IDLE state or INACTIVE state to RRC CONNECTED state, it applies the NR sidelink communications parameters provided in this new state. Until the new configuration is acquired, the selected resources for establishing the sidelink communication are derived from the configuration in the previous RRC state. This ensures seamless communication and maintains the integrity of ongoing sidelink operations during state transitions (see, section 5.8.9.1.1 of TS 38.331).

[0056] Based on the technical specifications of the 3GPP, regardless of UE's RRC state, the UE may acquire NR sidelink communications parameters by:- RRC reconfiguration, if the UE is in a RRC connected state or if the UE is in an IDLE / INACTIVE state, while the previous state is RRC connected; or- By system information, if the UE is in an IDLE / INACTIVE state and not being in connected state previously.

[0057] In addition, according to 3GPP (see, section 16.9.3.3 of TS 38.300), the UE is allowed to autonomously select suitable resources for sidelink communication from an exceptional transmission resource pool.

[0058] Furthermore, RRC Protocol Specification and Conditions for NR sidelink communication and / or discovery operation is defined in section 5.8.2 of TS 38.331 as following:

[0059] As explained above, the UE may support the sidelink communication in all RRC states and applies NR sidelink parameters upon transitioning to RRC-connected state. Until then, the UE may use the sidelink configuration from the previous state. NR sidelink parameters can be acquired via RRC reconfiguration when in RRC-connected or from system information when the UE is in IDLE / INACTIVE state.

[0060] 2. Network Energy Saving (NES)

[0061] FIG. 2 is a schematic diagram illustrating deployments of cells including the NES cell in which example embodiments of the present disclosure may be implemented.

[0062] The present disclosure may be based on the progress and discussion for Release 19 (Rel-19) on NES enhancements. The objectives Release 19 Work Item related to the on- demand system information block 1 (OD-SIB1) operation for network energy saving (NES) was the following:- Study procedures and signaling method(s) to support on-demand SIB1 for UEs in idle / inactive mode, including:-- Triggering method by uplink wake-up-signal using an existing signal / channel, and-- Wake-up-signal configuration provisioning to UE; and- Information exchange between gNBs at least for the configuration of wake-up signal, if necessary.

[0063] The NES cell operating with OD-SIB1 mode will not periodically broadcast the SIB1 as per legacy procedure. Instead, the SIB1 will be provided on-demand, i.e., based on the UE (in RRC idle or RRC inactive) requesting its transmission. As can be seen from the objectives, the UE will trigger the SIB1 transmission by sending a wake-up signal (WUS). This requires that the UE is configured with resources and information to transmit the WUS. FIG.2(a) discloses the case when the UE 102 (e.g., NES UE) obtains the UL WUS configuration from a cell A (or normal cell) which is an anchor or coverage cell (a cell with regular SIB1 transmission), and FIG. 2(b) discloses the case when the UE 102 obtains the UL WUS configuration from the NES cell.

[0064] In the present disclosure, the NES cell is operating with an OD-SIB1 mode (or, NES mode), which means that the SIB1 is only provided based on a request from a UE. In this case, UEs must be 1) configured with the necessary information required to transmit the WUS to the NES Cell and the UEs are 2) capable of transmitting the WUS to NES Cell. However, there can be possible two situations according to the cases of FIG.2.

[0065] For example, referring back to FIG. 2(a), a network device 104a controls / manages a cell A. UE 100 is a non-NES UE (e.g., UEs supporting NR) and it connects with the network device 104a. In the area of cell A, a NES cell that is controlled / managed by a network device 104b. The network device 104b is a NES capable network device supporting the NES. In thiscase, the UE 102 which is able to support beyond 5G (e.g., 6G) and / or NES locates in the NES cell. Even though UE 100 located in the NES cell area, the UE 100 has no ability to access the NES cell.

[0066] Under this situation, at least one non-NES UE 100 may experience poor radio channel conditions towards Cell A and may not be able to establish a reliable link to Cell A (e.g., emergency case, sensing, etc.), to achieve its desired QoS requirement. However, the non-NES UEs 100 are in good coverage to an NES cell, but the NES cell is not providing SIB1 due to the OD-SIB1 (NES) mode. Note that, the non-NES UEs are not NES-capable, and thus, have no understanding of WUS configuration and are also not capable of signaling WUS to NES Cell for OD-SIB1 request. Hence, such non-NES UEs are not able to start service in the NES cell, even if the NES cell is determined as suitable for communication.

[0067] Referring back to FIG. 2(b), the network device 104b is the NES capable network device supporting the NES, and the NES cell is a standalone cell. In this case, the UE 102 which is able to support beyond 5G (e.g., 6G) and / or NES locates in the NES cell, thus the UE 102 may receive the WUS configuration from the network device 104b of the NES cell.

[0068] At least one NES-capable UEs 102 may be required to have a WUS configuration for requesting OD-SIB1 from a NES cell. The WUS configuration can be signaled to the NES- capable UEs 102 with an RRC release message or in SIBx. However, in the case of the standalone scenario, the newly arriving idle / inactive state UEs (e.g., UE 100), whose RRC connection was released in a cell different from the NES cell, may not have a valid WUS configuration to request SIB1 towards the current NES cell. Therefore, the access to the NES cell is barred for the UE 100. Hence, the following problems need to be addressed efficiently in a practical, clear, and proper manner.

[0069] Isolated non-NES UEs 100 of FIG. 2(a) are unable to access the NES cell operating in the OD-SIB1 mode, which can be critical, e.g., when immediate communication and seamless connectivity are necessary particularly for some type of services (e.g., emergency case, sensing, etc.).

[0070] In another case, the newly arriving NES-capable idle / inactive UEs 100 of FIG. 2(b) which are not aware of the WUS configuration to be used for requesting SIB1 in a standalone scenario.

[0071] The starting point for beyond 5G (e.g., 6G) design is to ensure seamless connectivity while ensuring network energy savings, thus the above highlighted issues may be prerequisites for on-demand operations and need to be addressed.

[0072] The present disclosure may exploit the sidelink (SL) communications framework. For example, the non- NES UEs 100 of FIG. 2(a) may relay the information to the NES cell via sidelink and provide indication / request to fallback to legacy broadcast SIB1 operation to be able to camp and to initiate service in a NES cell. Alternatively or additionally, the non-NES UE 100 of FIG. 2(a) may transmit OD-SIB request to the NES UEs via the sidelinkcommunication and receives the OD-SIB from the NES UEs via the SL.

[0073] For the newly arriving NES capable UEs of FIG. 2(b) in an RRC idle / inactive state may obtain the WUS configuration for initiating the on-demand SIB1 acquisition and / or SIB1 payload over the sidelink and enabling them to camp and to initiate service in NES cell.

[0074] The NES cells of the present disclosure may switch between a broadcast mode (e.g., regular SIB1 broadcast mode) and on-demand SIB1 mode (e.g., NES mode) as required by the network operations.

[0075] 3. Cooperation for on-demand services

[0076] Hereinafter, various aspects of the present disclosure are explained more in detail. In order to explain the various aspects of the disclosure, the technical features disclosed by FIG. 1 and the description thereof and by sections 1 to 2 above may be applied.

[0077] 3.1 A first aspect of the disclosure

[0078] FIG. 3 is a schematic flow diagram illustrating some example embodiments according to the first aspect of the disclosure.

[0079] Referring to FIG. 3, the first user device 100, the second user device 102 and the network device 104 are disclosed. The first user device 100 may be the UE 100 (e.g., a non- NES UE or 5G UEs supporting up to Rel-18) of FIGs. 1 or 2(a), and the second user device 102 may be the UE 102 (e.g., a 6G and / or NES UE supporting NES) of FIGs. 1 or 2(a). There may be more than one user device in the cell (not shown). The network device 104 may be the network device 104b of FIG. 2(a) supporting the NES. That is to say, the first aspect is related to the situation explained in FIG. 2(a).

[0080] Regarding the first user device 100, an apparatus for communication is to be explained. The apparatus may perform a method Al, and the apparatus may be the first user device 100 (or referred to a first apparatus) supporting legacy communication system (e.g., LTE, LTE-A, and / or 5G etc.). Alternatively or additionally, the apparatus may be embedded or to be embedded in the first user device 100.

[0081] Referring to FIG. 3, method Al includes steps S310, S340 and S360 which are performed by the apparatus (i.e., the first user device 100).

[0082] The apparatus for Al may comprise at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to perform at least one of the following methods Al, A2, and A6 to A9.

[0083] Alternatively or additionally, the apparatus for Al may comprise one or more means to perform at least one of the following methods Al, A2, and A6 to A9.

[0084] At step S310, the apparatus 100 (e.g., the first user device 100, non-NES UE)transmits, to a second user device 102 (i.e., NES capable UE), a request message requesting an access assistance to access a cell that is managed / controlled by the network device and is in an on-demand signal mode (or referred to as a first mode, on-demand mode or NES mode).

[0085] At step S340 the apparatus 100 receives, from the second user device 102, a response message comprising assistance information.

[0086] At step S360, the apparatus 100 receives, from the cell which is in a broadcast mode (or referred to as a second mode, default mode, or normal mode), a signal based on the assistance information. The mode of the cell has been transited from the on-demand signal mode to the broadcast mode at step S350 to be explained.

[0087] As a method A2, the apparatus 100 of Al is further caused to perform the steps of:- receiving, from the second user device 102, a request message requesting at least one measurement associated with a cell identifier of the cell; and- transmitting, to the second user device 102, a response message comprising at least one measurement result.

[0088] The at least one measurement may include at least one of a synchronization signal block reference signal received power (SSB-RSRP) measurement, reference signal received quality (RSRQ) measurement or received signal strength indicator (RSSI) measurement.

[0089] Referring to FIG. 3, method A3 includes steps of S310, S320, S330, and S340.

[0090] Regarding the second user device 102, an apparatus for communication is to be explained. The apparatus for method A3 may be the second user device 102 (or referred to a second apparatus, or NES capable UE) supporting the NES communication system (e.g., beyond 5G or 6G etc.). Alternatively or additionally, the apparatus may be embedded or to be embedded in the second user device 102.

[0091] The apparatus for A3 may comprise at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to perform at least one of the following methods A3 to A9.

[0092] The apparatus for A3 may comprise one or more means to perform at least one of the following methods A3 to A9.

[0093] At step S310, the apparatus 102 receives, from a first user device 100 (e.g., the non- NES UE), a request message requesting an access assistance to access a cell which is in an on-demand signal mode (or referred to as a first mode, on-demand mode or NES mode). The on-demand signal mode may includes OD-SIB1 mode.

[0094] At step S320, the apparatus 102 transmits, to the cell which is in the OD-SIB mode, a wake up signal (WUS) including additional information related to the assistance to access the cell. The WUS may be transmitted via a physical random access channel (PRACH) or message (Msg) 3 during a RACH procedure. Additionally or alternatively, an assistancerequest message may be used instead of the WUS.

[0095] At step S330, the apparatus 102 receives, from the cell, a WUS response in response to the WUS. The WUS response may comprises assistance information.

[0096] At step S340, the apparatus 102 transmits, to the first user device 100, a response message comprising the assistance information.

[0097] The assistance information may indicate at least one of 1) one or more beams to be used to transmit the signal or 2) timing information related to the signal.

[0098] At step S350, the network device 104 may changes the mode from the on-demand signal mode to the broadcast mode. Then, the network device 104 may broadcast the signal in the cell at step 360.

[0099] As a method A4, the apparatus 102 of A3 may further caused to perform the steps of:- transmitting, to the first user device 100, a request message requesting at least one measurement (e.g., the SSB-RSRP, RSSI, or RSRQ measurement) associated with a cell identifier of the cell;- receiving, from the first user device 100, a response message comprising at least one measurement result; and- determining whether the first user device 100 is in-coverage to the cell based on the at least one measurement result.

[0100] As a method A5, the additional information of A3 or A4 may comprise a beam index indicative of a best beam of the first user device 100.

[0101] As a method A6, the response message comprising at least one measurement result of methods A2, A4 or A5 may further comprise a beam index (SSB beam index) indicative of a best beam.

[0102] At a method A7, the request message and the response message of any one of the methods Al to A6 may be transmitted and received via a sidelink, respectively.

[0103] As a method A8, the assistance information of any one of methods Al to A7 may indicate at least one or more beams to be used to transmit the signal or timing information related to the signal.

[0104] As a method A9, the on-demand signal mode of any one of methods Al to A8 may be an on-demand system information block (SIB) mode. In this case, the signal may be an SIBx (where, x = 1, 2, 3, ... or , 21) or an SSB.

[0105] In order to implement the present disclosure, a computer program comprising instructions, which when executed by the apparatus (e.g., the first user device 100 or the second user device 102), may cause the apparatus to perform the method of any one of Al to A9. In this case, a computer readable storage medium may have stored thereon the computer program. The computer readable storage medium may be a non-transitorycomputer readable medium.

[0106] FIG. 4 is a schematic flow diagram illustrating example embodiments according to the first aspect of the disclosure.

[0107] Hereinafter, it is explained that the case when the first aspect of the disclosure is applied to FIG. 2(a).

[0108] Referring to FIG. 4 and FIG. 2(a), the cell A (or referred to as a first cell or non-NES cell) may be a normal cell (e.g., primary cell (Pcell), primary secondary cell (PScell), or a serving cell (Scell)) that is controlled and / or managed by the network device 104a (or referred to as a first network device). Within the coverage of the cell A, one or more non- NES UEs and NES UEs may camp on it. The first user device 100 is one of the non-NES UEs. Meanwhile, the NES cell (or referred to a cell B or a second cell) may be located within the coverage of the cell A (or the coverage of the NES cell may be partially overlapped with that of the cell A). Within the coverage of the NES cell, one or more NES capable UEs may camp on it. The second user device 102 is one of the NES capable UEs. The NES cell may be controlled or managed by the network device 104b (or referred to as a second network device) of FIG. 2(a) or the network device 104 of FIG.3. The first user device 100 may be the UE 100 of FIGs. 1 or 2(a), and the second user device 102 may be the UE 102 of FIGs. 1 or 2(a). There may be more than one user devices in the cell (not shown).

[0109] In the embodiments of the present disclosure, when the user devices transmit or receive the signals or messages to or from the cells, the actual end points of the communication are the user devices and the network devices.

[0110] Referring to FIG. 4, the first user device 100 (e.g., non-NES UE) and the second user device 102 may be preconfigured with parameters required for sidelink communication setup. For example, the network device 104a of the cell A transmits a configuration for the sidelink communication set up to the first user device 100 and the network device 104b of the cell B transmits a configuration forthe sidelink communication set up to the second user device 102. Alternatively, the network device 104a of the cell A configures the sidelink communication set up both the first user device 100 and the second user device 102.

[0111] At step S405, the NES cell (i.e., the cell B) is in the on-demand SIB1 mode. The NES cell may have transited from the broadcast mode (i.e., normal mode, or default mode) to the OD-SIB1 mode. The broadcast mode stands for a first mode that the network device 104b broadcasts the SIB1 (or SSB) based on a pre-determined period, and the OD-SIB1 mode stands for a second mode that the network device 104B transmits the SIB1 (or SSB) only if it is requested by the specific user device.

[0112] At step S410, the first user device 100 may determine whether the cell B is barred or not. In order to do this, the first user device 100 may have received and measured SSBs transmitted from both Cell A and NES cell. If the NES cell doesn't provide SIB1 because the NES cell operates in the OD-SIB1 mode (see, S405), then the NES cell is identified as 'barred' after a specified wait timer that is related to the SIB1 transmission periodicity (e.g., 160ms).

[0113] At step S415, the first user device 100 may detect one or more events. For example, after or during the SSB measurements, if the first user device 100 may have experienced poor channel conditions towards the cell A and identified it as less suitable to achieve its quality of service (QoS) requirements. In contrast, if the NES cell provides good radio conditions to the first user device 100, hence considered as suitable for camping and initiating service during emergency situations, sensing applications where immediate / priority communication and seamless reliable connection is critical, and / or isolated situation.

[0114] The first user device 100 determined that the NES cell is barred, the first user device 100 is not able to access to the NES cell. Thus, at step S420, the first user device 100 may perform a sidelink discovery procedure based on the preconfigured sidelink communication setup. That is, the non-NES UE 100 may initiate the sidelink communication session using the legacy procedures. Additionally or alternatively, the second user device (i.e., the NES- capable UE 102) may initiate the sidelink discovery procedure.

[0115] At step S425, the first user device 100 may request the second user device 102 for providing assistance to access the NES cell using a sidelink message. This can be achieved via a direct sidelink communication path established between two UEs over the PC5 interface. For example, in order to request the assistance, the first user device may transmit an assistant request message to the second user device via the sidelink (SL).

[0116] At step S430, the second user device 102 may inquire to the first user device 100 to provide SSB-RSRP measurements associated with the cell ID. For example, the second user device 102 may transmit the measurement request message to the first user device 100 to request the SSB-RSRP measurement (In the embodiments of the first aspect of the present disclosure, one of RSSI and RSRQmeasurements may be used additionally or instead of SSB-RSRP measurements).

[0117] At step S435, the first user device 100 may transmit a measurement response message (or measurement report message) comprising measurement results of the SSB- RSRP measurements.

[0118] At step S440, upon reception of the measurement response message, the second user device 102 may check if the first user device 100 is in-coverage to the NES cell and can camp, e.g., by comparing the SSB-RSRP measurements. For example, the second user device 102 may have performed SSB-RSRP measurements for the NES cell periodically, requested, or event triggered manner. Therefore, the second user device 102 may compare the reported SSB-RSRP results and the measured SSB-RSRP values.

[0119] Thus, at step S445b, if the second user device 102 determines the first user device 100 is not proper to camp on the NES cell at step S440, then the second user device 102 may transmit the NACK signal to the first user device 100 to deny access to the NES cell.

[0120] At step S445a, if the second user device 102 determines the first user device 100 is proper to camp on the NES cell at step S440, then the second user device 102 may transmitWUS signal to the network device 104b of the NES cell (i.e., cell B).

[0121] Alternatively or additionally, steps S430, S435, S440, S445b, and S445a may be optional. Thus, these steps may not be performed. Meanwhile, steps S430 to S445 ensure that the first user device 100 has minimum required SSB-RP measurements to the NES cell, and thus, avoid any redundant waking-up of NES cell.

[0122] Alternatively or additionally, regardless of steps S430 to S445, when the second user device 102 receives the assistance request message (at S420), the second user device 102 transmits an assistance request message to the NES cell, at step S445a. The assistance request may be transmitted by using WUS signal. The WUS may be transmitted by via a RACH preamble (i.e., PRACH) or Msg 3 during the RACH procedure.

[0123] At step S445a, when the second user device 102 sends the assistance request to NES cell at step 445a, the assistance request may include any additional information received (or derived) from the first user device 100 in the above steps.

[0124] In one possible example case, the additional information may comprise at least one index of at least one SSB beam (e.g., best SSB beam index). For example, the second user device 102 may identify or derive the best SSB beam for the first user device from the received SSB-RSRP measurements. Alternatively or additionally, the first user device 100 may measure the best beam and provide the beam index to the second user device at step S425 or S435. Note that it is less likely that both user devices 100, 102 belong to the same beam. Thus, the second user device may send the WUS (e.g., PRACH and / or Msg3 of random access (RA) procedure, etc) associated with the best SSB beam indicated by the first user device, rather than on its own best SSB beam. This ensures that the NES cell transmits the on-demand signal (e.g., SIB1 or SSB) associated on the best SSB beam indicated by the non- NES UE, thereby enabling it to camp onto the (NES) cell. The best SSB beam may be determined by the first user device 100 when the first user device received the SSBs (or MIB) of the NES cell.

[0125] Upon reception of the assistant request (e.g., WUS), at step S450, the network device 104b of the NES cell may decide to continue the current OD-SIB1 mode of operation or fallback to the broadcast mode (e.g., the legacy regular SIB1 transmission mode).

[0126] If the network device 104b decided to transfer to the broadcast mode, the NES cell may provide an indication including any additional information for the first user device. For example, at step S455, the network device 104b of the NES cell may transmit WUS response message comprising the assistance information.

[0127] In one possible example of the aspect, the assistance information may be, but not limited to, the indication on which SSB beam(s) will be used to transmit the signal (e.g., SIB1 or SSB). Additionally or alternatively, the WUS response message may include timing information for when the signal (e.g., SIB1 or SSB) will be transmitted (or broadcast), etc.

[0128] At step 460, the second user device 102 may provide the assistance information(e.g., received indication / information) to the first user device 100.

[0129] At step 465, the first user device 100 may receive and decode the signal (e.g., signal including the SIB1 or SSB etc.) based on the assistance information transmitted from the second user device 102. For example, the first user device 100 may receive the signal by using the indicated SSB beam at the time indicated by the timing information.

[0130] FIG. 5 illustrates one of embodiments according to the first aspect of the disclosure.

[0131] The pre-requisite of FIG. 5 is the same as that of FIG. 4. The detailed explanations of FIG. 5 can be referred to the same reference numbers of FIG. 4.

[0132] The NES UE 102 (or 6G capable UE) is in a RRC connected state with the NES cell that is in the NES mode for OD-SIB1 operation. The NES UE 102 may monitor and receive the SSB broadcast from the NES cell (S410). In this case, the non-NES UE 100 has no RRC connected state with the NES cell. When the non-NES UE 100 receives the SSB from the NES cell, the non-NES UE determines it is barred (S410).

[0133] The non-NES UE 100 and the NES UE may perform a sidelink UE discovery procedure and initiate SL communication (S420).

[0134] The non-NES UE 100 may transmit an assistance request to the NES UE 102 (S425).

[0135] Upon receiving the assistance request from the non-NES UE 100, the 6G / NES UE may transmit an uplink WUS to the NES cell (S445a).

[0136] When the NES cell receives the UL WUS from the NES UE, the NES cell may transit from the NES mode to the broadcast mode to perform the broadcast SIB1 operation. Then the NES cell broadcasts SIB1 within its coverage (S465).

[0137] If the non-NES UE receives the SIB1, then the non-NES UE may receive necessary system information based on the received SI Bl.

[0138] 5.2 A second aspect of the disclosure

[0139] FIG. 6 is a schematic flow diagram for explaining various methods according to the second aspect of the disclosure.

[0140] Referring to FIG. 6, the first user device 100, the second user device 102 and the network device 104 are disclosed. The first user device 100 and the second user device 102 may be a UE supporting beyond 5G (e.g., 6G) and / or NES of FIGs. 1 or 2(b). There may be more than two user devices in the cell (not shown) including the first and second user devices. In this case, it is assumed that the UE 100 is a UE that camps on the NES cell after the cell has transited to the NES mode. The network device 104 may be the network device 104b of FIG. 2(b) supporting the NES cell. That is to say, the second aspect is related to the situation explained in FIG. 2(b).

[0141] Regarding the first user device 100, an apparatus for communication is to beexplained. The apparatus may perform method Bl, and the apparatus may be the first user device 100 (or referred to a first apparatus). Alternatively or additionally, the apparatus may be embedded or to be embedded in the first user device 100.

[0142] Referring to FIG. 6, method Bl includes steps S610 and S620 which are performed by the apparatus (i.e ., the first user device 100).

[0143] The apparatus for Bl may comprise at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to perform at least one of the following methods B1-B4 and B8-B13.

[0144] Alternatively or additionally, the apparatus for Bl may comprise one or more means to perform at least one of the following methods B1-B4 and B8-B13.

[0145] At step S610, the apparatus (hereinafter referred to as the first user device 100) transmits, to a second user device 102, a request message requesting to access a cell which is in an on-demand signal mode.

[0146] At step S620, the first user device 100, receives, from the second user device, a response message comprising assistance information related to the on-demand signal mode.

[0147] As a method B2, the assistance information of method Bl may comprise a wake up signal (WUS) configuration that is to be used to access the cell. The WUS configuration may be used to request an on-demand signal.

[0148] Method B3 may further comprise steps of S630 and S640 in addition to method Bl or B2. For example, at step S630, the first user device 100 may transmit, to a network device 104, a WUS to request an on-demand signal based on the WUS configuration. At step S640, the first user device may receive, from the network device, the on-demand signal transmitted in response to the WUS.

[0149] As a method B4, the first user device 100 may be further caused to perform steps of:- receiving, from the second user device, a request message requesting at least one measurement (e.g., SSB-RSRP measurement) associated with a cell identifier of the cell; and- transmitting, to the second user device, a response message comprising at least one measurement result.

[0150] Referring to FIG. 6, method B5 includes steps of S610 and S620.

[0151] Regarding the second user device 102, an apparatus for communication is to be explained. The apparatus for method B5 may be the second user device 102 (or referred to as a second apparatus, or NES capable UE) supporting the NES communication system (e.g., beyond 5G or 6G etc.).

[0152] The apparatus for B5 may comprise at least one processor, and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatusat least to perform at least one of the following methods B5 to B13.

[0153] The apparatus for B5 may comprise one or more means to perform at least one of the following methods B5 to B13.

[0154] At step A610, the apparatus (hereinafter referred to as the second user device 102) receives, from the first user device 100, a request message requesting an access assistance to access a cell which is in an on-demand signal mode.

[0155] At step A620, the second user device 102 transmits, to the first user device 100, a response message comprising the assistance information related to the on-demand signal mode.

[0156] As a method B6, the assistance information of B5 may comprise a wake up signal (WUS) configuration that is to be used to access the cell.

[0157] As a method B7, the second user device of B5 or B6 may be further caused to perform steps of:- transmitting, to the first user device, a request message requesting at least one measurement associated with a cell identifier of the cell;- receiving, from the first user device, a response message comprising at least one measurement result; and- determining whether the first user device is in-coverage to the cell based on the at least one measurement result.

[0158] The at least one measurement of B7 may include an SSB-RSRP measurement.

[0159] As a method B8, the response message, comprising at least one measurement result, of B4 or B7 may further comprise a beam index (e.g., SSB beam index) indicative of a best beam.

[0160] As a method B9, the request message and the response message of any one of methods Bl to B8 may be transmitted and received via a sidelink, respectively.

[0161] As a method B10, the assistance information of methods Bl or B5 may comprise an on-demand signal related to the on-demand signal mode.

[0162] As a method Bll, the on-demand signal of B10 may have been stored at the second user device.

[0163] As a method B12, the assistance information of any one of methods Bl to Bll may indicates at least one of 1) one or more beams to be used to transmit the on-demand signal or 2) timing information related to the on-demand signal.

[0164] As a method B13, the on-demand signal mode of any one of methods Bl to B12 may be an on-demand system information block (SIB) mode. In this case, the on-demand signal may be an on-demand SIB. The on-demand signal mode may be an OD-SSB mode and the on-demand signal may be an SSB.

[0165] FIG. 7 is a schematic flow diagram illustrating example embodiments according to the second aspect of the disclosure.

[0166] Hereinafter, it is explained that the case when the second aspect of the disclosure is applied to FIG. 2(b).

[0167] Referring to FIG. 7 and FIG. 2(b), NES cell (or referred to as cell B or a second cell) may be a standalone cell that is apart from cell A. Within the coverage of the NES cell, one or more NES capable UEs may camp on it. The first and second user devices 100, 102 are two of the NES capable UEs of FIGs. 1 or 2(b). The NES cell may be controlled or managed by the network device 104b (or referred to as a second network device) of FIG. 2(b) or the network device 104 of FIG. 7. There may be more than one user devices in the NES cell (not shown).

[0168] In the embodiments of the present disclosure, when the user devices transmit or receive the signals or messages to or from the cells, the actual end points of the communication are the user devices and the network devices.

[0169] Referring to FIG. 7, the first user device 100 and the second user device 102 may be preconfigured with parameters required for sidelink communication setup. For example, the network device 104b of NES cell (e.g., cell B) may transmit a configuration for the sidelink communication set up to the second user device 102. At that moment, it is assumed that the first user device is not in the coverage of the NES cell.

[0170] Before switching to OD-SIB1 mode, at step S705, the NES cell was operating in the broadcast mode (e.g., referred to as a normal mode, regular mode or default mode). During the broadcast mode, the network device 104b may transmit or broadcast a WUS configuration to the second user device 102 via 1) a RRC release message or 2) a SIBx message (where, x=l, 2, ..., or 21). In addition, the network device 104b may transmit or broadcast an OD-SIB1 payload to the second user device 102 for subsequent network access. Hence, the second user device 102 may store and use the WUS configuration to access to the NES cell during the OD-SIB1 operation.

[0171] At step S710, the NES cell (i.e., the cell B) switches from the broadcast mode to the on-demand SIB1 mode. For example, the network device 104b of the NES cell may transit from the broadcast mode to the OD-SIB1 mode. The broadcast mode stands for a first mode that the network device 104b broadcasts the SIB1 (or SSB) based on a pre-determined period. The OD-SIB1 mode stands for a second mode that the network device 104B transmits the SIB1 (or SSB) only if it is requested by the specific user device.

[0172] In the case of the standalone scenario, newly arriving RRC idle / inactive state UE (e.g., the first user device 100) to the NES cell which is in the OD-SIB1 mode, whose RRC connection was released / suspended in a different cell (e.g., Cell A), not aware of the WUS configuration, may not be able to request an SIB1 from this NES cell. Hence, such first user device 100 should be provided with the required WUS configuration (and / or the OD-SIB1 payload) to be able to camp in the NES cell and to initiate service.

[0173] At 715, the first user device moves to the NES cell and receives SSBs from the NES cell. The first user device may derive a cell ID of the NES cell by decoding MIB of the NES cell and identify that the NES cell is in "OD-SIB1" mode.

[0174] The explanations of steps S720 to S745b are the same as steps of S420 to S445b, thus the details of steps S720 to S745b can be referred to steps of S420 to S445b. Hereinafter, different embodiments compared with FIG. 4 will be explained.

[0175] At step S745a, if the second user device 102 determines the first user device 100 is proper to camp on the NES cell at step S740, then the second user device 102 may transmit assistance response message to the first user device 100.

[0176] Additionally or alternatively, as a first embodiment of the second aspect of the present disclosure, the assistance response message may comprise WUS configuration stored by the second user device. For example, the first user device 100 may acquire the required UL WUS configuration from the second user device 102 via a direct sidelink communication path established between the two UEs over the PC5 interface. It is preassumed that the second user device 102 have already obtained the information directly from the NES cell before it transitions to the OD-SIB1 mode at step S705.

[0177] At step S755 the first user device 100 may transmit WUS directly to the NES cell based on the WUS configuration.

[0178] At step S760, the network device 104b of the NES cell may transmit on-demand SIB1 (or SSB) to the first user device in response to the WUS.

[0179] FIG. 8 illustrates the first embodiment according to the second aspect of the disclosure.

[0180] The pre-requisite of FIG. 8 is the same as that of FIG. 7. The detailed explanations of FIG. 8 can be referred to the same reference numbers of FIG. 7.

[0181] The NES UE 102 (hereinafter called as the second UE 102) is in a RRC connected state with the NES cell that is in the broadcast mode for broadcast SIB1 operation. The NES UE 102 receives UL WUS configuration via SIBx or RRC release message on the NES cell (S705).

[0182] After the NES cell has been transited to the NES mode, the NES UE 100 (hereinafter called as the first UE 100) may arrive within the NES cell.

[0183] The NES cell which is in the NES mode broadcast the SSB within the cell area. The frist UE 100 and second UE 102 may monitor and receive the SSB broadcast from the NES cell. In this case, the first UE may derive the cell ID from the SSB and it can identify that the NES cell is in the NES mode (S715).

[0184] The first UE 100 and the second UE 102 may perform a sidelink UE discovery procedure and initiate SL communication (S720).

[0185] The first UE 100 may transmit an assistance request to the second UE 102 via thesidelink (S725).

[0186] Upon receiving the assistance request from the first UE 100, the second UE 102 may transmit an assistance response including the WUS configuration to the first UE 100 (S745a).

[0187] The assistance response message may further include the additional information indicating an SSB beam index indicating a best beam of OD-SIB1 (or OD-SSB) and timing information indicating when the OD-SIB (or OD-SSB) is transmitted.

[0188] The first UE 100 may directly transmit WUS to request the OD-SIB1 to the NES cell based on the WUS configuration (S755).

[0189] The NES cell may transmit OD-SIB1 (or OD-SSB) to the first UE 100 in response to the WUS, and the first UE 100 may receive the OD-SIB1 (or OD-SSB) based on the additional information (S760).

[0190] Hereinafter, a second embodiment of the second aspect of the present disclosure is explained by using FIG. 7. For the second embodiment, steps of S755 and S760 are not performed.

[0191] Referring back to FIG. 7, the last SIB1 instance broadcasted by the NES cell (which may also include SIB1 payload) is stored at the second user device 102 before the NES cell transits to OD-SIB1 mode. Upon the assistance request (step 725) from the first user device, the second user device 102 may transmit the assistance response including the stored SIB1 payload via the sidelink operation (S745a).

[0192] The first user device 100 may receive necessary system information based on the SIB1 payload.

[0193] The second embodiment of the second aspect may lead to higher UE power consumption due to the transmission of stored SIB1 payload. However, it increases the network energy savings, e.g., by prolonging the ongoing sleep state of NES cell.

[0194] FIG. 9 illustrates the second embodiment according to the second aspect of the disclosure.

[0195] The pre-requisite of FIG. 8 is the same as that of FIG. 7. The detailed explanations of FIG. 9 can be referred to the same reference numbers of FIG. 7.

[0196] The NES UE 102 (hereinafter called as the second UE 102) is in a RRC connected state with the NES cell that is in the broadcast mode for broadcast SIB1 (and / or SSB) operation. The second UE 102 receives SIB1 broadcast on the NES cell and stores the SIB1 payload (S705).

[0197] After the NES cell has been transited to the NES mode, the 6G / NES UE 100 (hereinafter called as the first UE 100) may arrive within the NES cell.

[0198] The NES cell which is in the NES mode broadcast the SSB within the cell area. The first UE 100 and second UE 102 may monitor and receive the SSB broadcast from the NES cell. In this case, the first UE may derive the cell ID from the SSB and it can identify that theNES cell is in the NES mode (S715).

[0199] The first UE 100 and the second UE 102 may perform a sidelink UE discovery procedure and initiate SL communication (S720).

[0200] The first UE 100 may transmit an access assistance request to the second UE 102 via the sidelink (S725).

[0201] Upon receiving the assistance request from the first UE 100, the second UE 102 may transmit an assistance response including the SIB1 payload to the first UE 100 (S745a).

[0202] The first UE 100 may perform necessary operations with the NES cell based on the SIB1 payload.

[0203] Hereinafter the sidelink procedure that can be applied to step of S420 or S720 is explained.

[0204] In 5G NR, unicast communication over PC5 interface is supported. The same sidelink unicast communication may be supported even in 6G SL communication. A Direct Communication Request between (source) non-NES UE and NES-capable (destination) UE is achieved through PC5-S signaling. For this, the (source) non-NES UE may give priority for the SyncRef UE (which is NES-capable UE and also indicated as in coverage UE).

[0205] In other case, the (source) non-NES UE may act as SyncRef UE and initiate the SL discovery procedure to pair a link with NES-capable UE. The Tx UE's source layer 2 ID and destination UEs layer 2 ID are paired to identify a unicast link. The destination UE verifies the layer 2 ID. Sidelink data can be transmitted after this successful PC5 unicast link establishment. The same layer 2 IDs can be used for subsequent data transmissions.

[0206] The resource allocation mode for establishing the unicast communication between the UEs is resource allocation mode 2. The resource allocation mode 2 is categorized by the autonomous resource allocation done by the UE.

[0207] The UE is capable of transmitting data inside the NG-RAN coverage no matter what RRC state it is in. The side link resources are selected from the resource pools by using broadcast system information or dedicated signaling inside NG-RAN coverage. UE's preconfigurations are used outside of NG-RAN coverage. The resource pools are linked to certain validity areas. While the UE is moving in the assigned validity area, it does not need to change resource pools.

[0208] FIG. 10 illustrates an example of an apparatus 1000 comprising means for performing one or more of the example embodiments described above. For example, the apparatus 1000 may be, or comprise, or be comprised in, the first user device 100 or the second user device 102. The apparatus 1000 may perform the operations disclosed in FIGs. I to 9.

[0209] The apparatus 1000 may comprise a circuitry or a chipset applicable for realizing one or more of the example embodiments described above. For example, the apparatus 1000 may comprise at least one processor 1010. The at least one processor 1010 interprets instructions (e.g., computer program instructions) and processes data. The at least one processor 1010 may comprise one or more programmable processors. The at least one processor 1010 may comprise programmable hardware with embedded firmware and may, alternatively or additionally, comprise one or more application-specific integrated circuits (ASICs).

[0210] The at least one processor 1010 is coupled to at least one memory 1020. The at least one processor is configured to read and write data to and from the at least one memory 1020. The at least one memory 1020 may comprise one or more memory units. The memory units may be volatile or non-volatile. It is to be noted that there may be one or more units of non-volatile memory and one or more units of volatile memory or, alternatively, one or more units of non-volatile memory, or, alternatively, one or more units of volatile memory. Volatile memory may be for example random-access memory (RAM), dynamic random-access memory (DRAM) or synchronous dynamic random-access memory (SDRAM). Non-volatile memory may be for example read-only memory (ROM), programmable read-only memory (PROM), electronically erasable programmable read-only memory (EEPROM), flash memory, optical storage or magnetic storage. In general, memories may be referred to as non-transitory computer readable media. The term "non- transitory," as used herein, is a limitation of the medium itself (i.e., tangible, not a signal) as opposed to a limitation on data storage persistency (e.g., RAM vs. ROM). The at least one memory 1020 stores computer readable instructions that are executed by the at least one processor 1010 to perform one or more of the example embodiments described above. For example, non-volatile memory stores the computer readable instructions, and the at least one processor 1010 executes the instructions using volatile memory for temporary storage of data and / or instructions. The computer readable instructions may refer to computer program code.

[0211] The computer readable instructions may have been pre-stored to the at least one memory 1020 or, alternatively or additionally, they may be received, by the apparatus, via an electromagnetic carrier signal and / or may be copied from a physical entity such as a computer program product. Execution of the computer readable instructions by the at least one processor 1010 causes the apparatus 1000 to perform one or more of the aspects of the disclosure described above. That is, the at least one processor and the at least one memory storing the instructions may provide the means for providing or causing the performance of any of the methods and / or blocks described above.

[0212] The apparatus 1000 may further comprise, or be connected to, an input unit 1030. The input unit 1030 may comprise one or more interfaces for receiving input. The one or more interfaces may comprise for example one or more temperature, motion and / or orientation sensors, one or more cameras, one or more accelerometers, one or moremicrophones, one or more buttons and / or one or more touch detection units. Further, the input unit 1030 may comprise an interface to which external devices may connect to.

[0213] The apparatus 1000 may also comprise an output unit 1040. The output unit may comprise or be connected to one or more displays capable of rendering visual content, such as a light emitting diode (LED) display, a liquid crystal display (LCD) and / or a liquid crystal on silicon (LCoS) display. The output unit 1040 may further comprise one or more audio outputs. The one or more audio outputs may be for example loudspeakers.

[0214] The apparatus 1000 further comprises a connectivity unit 1050. The connectivity unit 1050 enables wireless connectivity to one or more external devices. The connectivity unit 1050 comprises at least one transmitter and at least one receiver that may be integrated to the apparatus 1000 or that the apparatus 1000 may be connected to. The at least one transmitter comprises at least one transmission antenna, and the at least one receiver comprises at least one receiving antenna. The connectivity unit 1050 may comprise an integrated circuit or a set of integrated circuits that provide the wireless communication capability for the apparatus 1000. Alternatively, the wireless connectivity may be a hardwired application-specific integrated circuit (ASIC). The connectivity unit 1050 may also provide means for performing at least some of the blocks or functions of one or more example embodiments described above. The connectivity unit 1050 may comprise one or more components, such as: power amplifier, digital front end (DFE), analog-to-digital converter (ADC), digital-to-analog converter (DAC), frequency converter, (de)modulator, and / or encoder / decoder circuitries, controlled by the corresponding controlling units.

[0215] It is to be noted that the apparatus 1000 may further comprise various components not illustrated in FIG. 10. The various components may be hardware components and / or software components.

[0216] The apparatus 1000 may perform or be applied with the embodiments described above. More specifically, the apparatus 1000 may be the first user device 100 or the second user device 102, and the user devices 100, 102 may be configured to perform one of the methods explained by using FIGs. 1 to 9.

[0217] FIG. 11 illustrates an example of an apparatus 1100 comprising means for performing one or more of the example embodiments described above. For example, the apparatus 1100 may be an apparatus such as, or comprising, or comprised in, the network entity or the network device 104, 104a, or 104b, and support the embodiments and examples described above.

[0218] The network device may also be referred to, for example, as a network element, a next generation radio access network (NG-RAN) node, a NodeB, an eNB, a gNB, a base transceiver station (BTS), a base station, an NR base station, a 5G base station, an access node, an access point (AP), a cell site, a relay node, a repeater, an integrated access and backhaul (IAB) node, an IAB donor node, a distributed unit (DU), a central unit (CU), abaseband unit (BBU), a radio unit (RU), a radio head, a remote radio head (RRH), or a transmission and reception point (TRP).

[0219] The apparatus 1100 may comprise, for example, a circuitry or a chipset applicable for realizing one or more of the example embodiments described above. The apparatus 1100 may be an electronic device comprising one or more electronic circuitries. The apparatus 1100 may comprise a communication control circuitry 1110 such as at least one processor, and at least one memory 1120 storing instructions 1122 which, when executed by the at least one processor, cause the apparatus 1100 to carry out one or more of the example embodiments described above. Such instructions 1122 may, for example, include computer program code (software). The at least one processor and the at least one memory storing the instructions may provide the means for providing or causing the performance of any of the methods and / or blocks described above.

[0220] The processor is coupled to the memory 1120. The processor is configured to read and write data to and from the memory 1120. The memory 1120 may comprise one or more memory units. The memory units may be volatile or non-volatile. It is to be noted that there may be one or more units of non-volatile memory and one or more units of volatile memory or, alternatively, one or more units of non-volatile memory, or, alternatively, one or more units of volatile memory. Volatile memory may be for example random-access memory (RAM), dynamic random-access memory (DRAM) or synchronous dynamic random-access memory (SDRAM). Non-volatile memory may be for example read-only memory (ROM), programmable read-only memory (PROM), electronically erasable programmable read-only memory (EEPROM), flash memory, optical storage or magnetic storage. In general, memories may be referred to as non-transitory computer readable media. The term "non-transitory," as used herein, is a limitation of the medium itself (i.e., tangible, not a signal) as opposed to a limitation on data storage persistency (e.g., RAM vs. ROM). The memory 1120 stores computer readable instructions that are executed by the processor. For example, non-volatile memory stores the computer readable instructions, and the processor executes the instructions using volatile memory for temporary storage of data and / or instructions.

[0221] The computer readable instructions may have been pre-stored to the memory 1120 or, alternatively or additionally, they may be received, by the apparatus, via an electromagnetic carrier signal and / or may be copied from a physical entity such as a computer program product. Execution of the computer readable instructions causes the apparatus 1100 to perform one or more of the functionalities described above.

[0222] The memory 1120 may be implemented using any suitable data storage technology, such as semiconductor-based memory devices, flash memory, magnetic memory devices and systems, optical memory devices and systems, fixed memory and / or removable memory.

[0223] The apparatus 1100 may further comprise or be connected to a communicationinterface 1130, such as a radio unit, comprising hardware and / or software for realizing communication connectivity with one or more wireless communication devices according to one or more communication protocols. The communication interface 1130 comprises at least one transmitter (Tx) and at least one receiver (Rx) that may be integrated to the apparatus 1100 or that the apparatus 1100 may be connected to. The communication interface 1130 may provide means for performing some of the blocks for one or more example embodiments described above. The communication interface 1130 may comprise one or more components, such as: power amplifier, digital front end (DFE), analog-to-digital converter (ADC), digital-to-analog converter (DAC), frequency converter, (de)modulator, and / or encoder / decoder circuitries, controlled by the corresponding controlling units.

[0224] The communication interface 1130 provides the apparatus with radio communication capabilities to communicate in the wireless communication network. The communication interface may, for example, provide a radio interface to one or more wireless communication devices. The apparatus 1100 may further comprise or be connected to another interface towards a core network such as the network coordinator apparatus or AMF, and / or to the access nodes of the wireless communication network.

[0225] The apparatus 1100 may further comprise a scheduler 1140 that is configured to allocate radio resources. The scheduler 1140 may be configured along with the communication control circuitry 1110 or it may be separately configured.

[0226] It is to be noted that the apparatus 1100 may further comprise various components not illustrated in FIG. 11. The various components may be hardware components and / or software components.

[0227] The apparatus 1100 may perform or be applied with the embodiments described above. More specifically, the apparatus 1100 may be the network device 104, and the network device 104 may be configured to perform one of the methods explained by using FIGs. I to 9.

[0228] The techniques and methods described herein may be implemented by various means. For example, these techniques may be implemented in hardware (one or more devices), firmware (one or more devices), software (one or more modules), or combinations thereof. For a hardware implementation, the apparatus(es) of example embodiments may be implemented within one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), graphics processing units (GPUs), processors, controllers, micro-controllers, microprocessors, other electronic units designed to perform the functions described herein, or a combination thereof. For firmware or software, the implementation can be carried out through modules of at least one chipset (for example procedures, functions, and so on) that perform the functions described herein. The software codes may be stored in a memory unit and executed by processors. The memory unit may be implemented within the processor or externally to the processor. Inthe latter case, it can be communicatively coupled to the processor via various means, as is known in the art. Additionally, the components of the systems described herein may be rearranged and / or complemented by additional components in order to facilitate the achievements of the various aspects, etc., described with regard thereto, and they are not limited to the precise configurations set forth in the given figures, as will be appreciated by one skilled in the art.

[0229] It will be obvious to a person skilled in the art that, as technology advances, the inventive concept may be implemented in various ways. The embodiments are not limited to the example embodiments described above, but may vary within the scope of the claims. Therefore, all words and expressions should be interpreted broadly, and they are intended to illustrate, not to restrict, the embodiments.

Claims

WHAT IS CLAIMED IS:

1. An apparatus comprising at least one processor, and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to perform: transmitting, to a second user device, a request message requesting an access assistance to access a cell which is in an on-demand signal mode; receiving, from the second user device, a response message comprising assistance information; and receiving, from the cell which is in a broadcast mode, a signal based on the assistance information.

2. The apparatus of claim 1, wherein the apparatus is further caused to perform: receiving, from the second user device, a request message requesting at least one measurement associated with a cell identifier of the cell; and transmitting, to the second user device, a response message comprising at least one measurement result.

3. An apparatus comprising at least one processor, and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to perform: receiving, from a first user device, a request message requesting an access assistance to access a cell which is in an on-demand signal mode; transmitting, to the cell, a wake up signal, WUS, including additional information related to the assistance to access the cell; receiving, from the cell, a WUS response in response to the WUS, the WUS response comprising assistance information; and transmitting, to the first user device, a response message comprising the assistance information.

4. The apparatus of claim 3, wherein the apparatus is further caused to perform: transmitting, to the first user device, a request message requesting at least one measurement associated with a cell identifier of the cell; receiving, from the first user device, a response message comprising at least one measurement result; and determining whether the first user device is in-coverage to the cell based on the at least one measurement result.

5. The apparatus of claim 3 or 4, wherein the additional information comprises a beam index indicative of a best beam of the first user device.

6. The apparatus of any one of claims 2, 4 and 5, wherein the response message comprising at least one measurement result further comprises a beam index indicative of a best beam.

7. The apparatus of any one of claims 1 to 6, wherein the request message and the response message are transmitted and received via a sidelink, respectively.

8. The apparatus of any one of claims 1 to 7, wherein the assistance information indicating at least one or more beams to be used to transmit the signal or timing information related to the signal.

9. The apparatus of any one of claims 1 to 8, wherein the on-demand signal mode is an on-demand system information block, SIB, mode, and wherein the signal is an SIB.

10. A method for communication, comprising: transmitting, to a second user device, a request message requesting an access assistance to access a cell which is in an on-demand signal mode; receiving, from the second user device, a response message comprising assistance information; and receiving, from the cell which is in a broadcast mode, a signal based on the assistance information.

11. The method of claim 10, further comprising: receiving, from the second user device, a request message requesting at least one measurement associated with a cell identifier of the cell; and transmitting, to the second user device, a response message comprising at least one measurement result.

12. A method for communication, comprising: receiving, from a first user device, a request message requesting an access assistance to access a cell which is in an on-demand signal mode; transmitting, to the cell (which is in the OD-SIB mode), a wake up signal, WUS, including additional information related to the assistance to access the cell; receiving, from the cell, a WUS response in response to the WUS, the WUSresponse comprising assistance information; and transmitting, to the first user device, a response message comprising the assistance information.

13. The method of claim 12, further comprising: transmitting, to the first user device, a request message requesting at least one measurement associated with a cell identifier of the cell; receiving, from the first user device, a response message comprising at least one measurement result; and determining whether the first user device is in-coverage to the cell based on the at least one measurement result.

14. The method of claim 12 or 13, wherein the additional information comprises a beam index indicative of a best beam of the first user device.

15. The method of any one of claims 11, 13 and 14, wherein the response message comprising at least one measurement result further comprises a beam index indicative of a best beam.

16. The method of any one of claims 10 to 15, wherein the request message and the response message are transmitted and received via a sidelink, respectively.

17. The method of any one of claims 10 to 16, wherein the assistance information indicating at least one or more beams to be used to transmit the signal or timing information related to the signal.

18. The method of any one of claims 10 to 17, wherein the on-demand signal mode is an on-demand system information block, SIB, mode, and wherein the signal is an SIB.

19. A computer program comprising instructions, which when executed by an apparatus, cause the apparatus to perform the method of any one of claims 10 to 18.

20. A computer readable storage medium having stored thereon the computer program of claim 19.

21. The computer readable storage medium of claim 20, wherein the computer readable storage medium is a non-transitory computer readable medium.

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