Early configuration message

Abstract

Example embodiments of the present disclosure are directed to an early configuration message. A method comprises receiving, from a network apparatus, an early configuration message prior to starting a random access channel (RACH) procedure or transitioning to a radio resource control (RRC) idle or inactive state, the early configuration message indicating at least one early configuration comprising a previous configuration used by the terminal apparatus in a previous RRC connected state or a reference configuration indicating the previous configuration; storing information associated with the previous configuration in the RRC idle or inactive state; receiving, from the network apparatus, a random access response (RAR) message comprising an indication associated with the at least one early configuration; and determining, based on at least the indication, a target early configuration of the at least one early configuration.

Description

EARLY CONFIGURATION MESSAGEFIELD

[0001] Various example embodiments of the present disclosure generally relate to the field of telecommunication and in particular, to methods, devices, apparatuses and computer readable storage medium for early configuration message.BACKGROUND

[0002] A communication network may serve as a facility that enables communications between two or more communication devices or provides communication devices access to a data network. A mobile or wireless communication network is one example of a communication network. A communication device may be provided with a service by an application server.

[0003] The communication network may operate in accordance with standards such as those provided by Third Generation Partnership Project (3GPP) or European Telecommunications Standards Institute (ETSI). Examples of standards provided by 3GPP are the so-called 3GPP standards for cellular technology generations, such as 3GPP standards for 4G technology, 5G technology, 6G technology etc.SUMMARY

[0004] In a first aspect of the present disclosure, there is provided a terminal apparatus. The terminal apparatus comprises at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the terminal apparatus to: receive, from a network apparatus, an early configuration message prior to starting a random access channel (RACH) procedure or transitioning to a radio resource control (RRC) idle or inactive state, the early configuration message indicating at least one early configuration; receive, from the network apparatus, a random access response (RAR) message comprising an indication associated with the at least one early configuration; and determine, based on at least the indication, a target early configuration of the at least one early configuration.

[0005] In a second aspect of the present disclosure, there is provided a network apparatus. The network apparatus comprises at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the network apparatus to: transmit an early configuration message to a terminal apparatus in a RRC connected state or transmitting the early configuration message to the terminal apparatus prior to a random access channel (RACH) procedurebeing initiated from the terminal apparatus, the early configuration message indicating at least one early configuration; determine, for the terminal apparatus, a target early configuration of the at least one early configuration; and transmit, to the terminal apparatus, a random access response (RAR) message comprising an indication associated with the target early configuration.

[0006] In a third aspect of the present disclosure, there is provided a method. The method comprises: receiving, at a terminal apparatus and from a network apparatus, an early configuration message prior to starting a random access channel (RACH) procedure or transitioning to a radio resource control (RRC) idle or inactive state, the early configuration message indicating at least one early configuration; receiving, from the network apparatus, a random access response (RAR) message comprising an indication associated with the at least one early configuration; and determining, based on at least the indication, a target early configuration of the at least one early configuration.

[0007] In a fourth aspect of the present disclosure, there is provided a method. The method comprises: transmitting, from a network apparatus an early configuration message to a terminal apparatus in a RRC connected state or transmitting the early configuration message to the terminal apparatus prior to a random access channel (RACH) procedure being initiated from the terminal apparatus, the early configuration message indicating at least one early configuration; determining, for the terminal apparatus, a target early configuration of the at least one early configuration; and transmitting, to the terminal apparatus, a random access response (RAR) message comprising an indication associated with the target early configuration.

[0008] In a fifth aspect of the present disclosure, there is provided a terminal apparatus. The terminal apparatus comprises means for receiving, from a network apparatus, an early configuration message prior to starting a random access channel (RACH) procedure or transitioning to a radio resource control (RRC) idle or inactive state, the early configuration message indicating at least one early configuration; means for receiving, from the network apparatus, a random access response (RAR) message comprising an indication associated with the at least one early configuration; and means for determining, based on at least the indication, a target early configuration of the at least one early configuration.

[0009] In a sixth aspect of the present disclosure, there is provided a network apparatus. The network apparatus comprises means for transmitting an early configuration message to a terminal apparatus in a RRC connected state or transmitting the early configuration message to the terminal apparatus prior to a random access channel (RACH) procedure being initiated from the terminal apparatus, the early configuration message indicating at least one early configuration; means for determining, for the terminal apparatus, a target early configuration of the at least one earlyconfiguration; and means for transmitting, to the terminal apparatus, a random access response (RAR) message comprising an indication associated with the target early configuration.

[0010] In a seventh aspect of the present disclosure, there is provided a computer readable medium. The computer readable medium comprises instructions stored thereon for causing an apparatus to perform at least the method according to the third or fourth aspect.

[0011] In an eighth aspect of the present disclosure, there is provided a terminal apparatus. The terminal apparatus comprises at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the terminal apparatus to: receive, from a network apparatus, an early configuration message prior to starting a random access channel (RACH) procedure or transitioning to a radio resource control (RRC) idle or inactive state, the early configuration message indicating at least one early configuration comprising a previous configuration used by the terminal apparatus in a previous RRC connected state or a reference configuration indicating the previous configuration; store information associated with the previous configuration in the RRC idle or inactive state; receive, from the network apparatus, a random access response (RAR) message comprising an indication associated with the at least one early configuration; and determine, based on at least the indication, a target early configuration of the at least one early configuration.

[0012] In a ninth aspect of the present disclosure, there is provided a method. The method comprises: receiving, at a terminal apparatus and from a network apparatus, an early configuration message prior to starting a random access channel (RACH) procedure or transitioning to a radio resource control (RRC) idle or inactive state, the early configuration message indicating at least one early configuration comprising a previous configuration used by the terminal apparatus in a previous RRC connected state or a reference configuration indicating the previous configuration; storing information associated with the previous configuration in the RRC idle or inactive state; receiving, from the network apparatus, a random access response (RAR) message comprising an indication associated with the at least one early configuration; and determining, based on at least the indication, a target early configuration of the at least one early configuration.

[0013] In a tenth aspect of the present disclosure, there is provided a terminal apparatus. The terminal apparatus comprises means for receiving, from a network apparatus, an early configuration message prior to starting a random access channel (RACH) procedure or transitioning to a radio resource control (RRC) idle or inactive state, the early configuration message indicating at least one early configuration comprising a previous configuration used by the terminal apparatus in a previous RRC connected state or a reference configuration indicating the previous configuration; means for storing information associated with the previous configuration in the RRC idle or inactive state; meansfor receiving, from the network apparatus, a random access response (RAR) message comprising an indication associated with the at least one early configuration; and means for determining, based on at least the indication, a target early configuration of the at least one early configuration.

[0014] In an eleventh aspect of the present disclosure, there is provided a computer readable medium. The computer readable medium comprises instructions stored thereon for causing an apparatus to perform at least the method according to the ninth aspect.

[0015] It is to be understood that the Summary section is not intended to identify key or essential features of embodiments of the present disclosure, nor is it intended to be used to limit the scope of the present disclosure. Other features of the present disclosure will become easily comprehensible through the following description.BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Some example embodiments will now be described with reference to the accompanying drawings, where:

[0017] FIG. 1 illustrates an example communication environment in which example embodiments of the present disclosure can be implemented;

[0018] FIG. 2A illustrates a signaling flow of an example process for an early configuration message in accordance with some example embodiments of the present disclosure;

[0019] FIG. 2B illustrates a signaling flow of another example process for an early configuration message in accordance with some example embodiments of the present disclosure;

[0020] FIG. 2C illustrates a signaling flow of an example process for buffering information associated with a previous configuration in accordance with some example embodiments of the present disclosure;

[0021] FIG. 3 illustrates a signaling flow of an example process for an early configuration of channel state information (CSI) feedback in accordance with some example embodiments of the present disclosure;

[0022] FIG. 4 illustrates a flowchart of an example process for an early configuration of CSI reporting in accordance with some example embodiments of the present disclosure;

[0023] FIG. 5 illustrates a flowchart of an example process for an early configuration of a sounding reference signal (SRS) transmission in accordance with some example embodiments of the present disclosure;

[0024] FIG. 6 illustrates a flowchart of a method implemented at a terminal apparatus in accordance with some example embodiments of the present disclosure;

[0025] FIG. 7 illustrates a flowchart of a method implemented at a network apparatus in accordance with some example embodiments of the present disclosure;

[0026] FIG. 8 illustrates a flowchart of another method implemented at a terminal apparatus in accordance with some example embodiments of the present disclosure;

[0027] FIG. 9 illustrates a simplified block diagram of a device that is suitable for implementing example embodiments of the present disclosure; and

[0028] FIG. 10 illustrates a block diagram of an example computer readable medium in accordance with some example embodiments of the present disclosure.

[0029] Throughout the drawings, the same or similar reference numerals represent the same or similar element.DETAILED DESCRIPTION

[0030] 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 can be implemented in various manners other than the ones described below.

[0031] In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skills in the art to which this disclosure belongs.

[0032] 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, or characteristic, but it is not necessary that every embodiment includes the particular feature, structure, 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 an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

[0033] It shall be understood that although the terms “first,” “second,”..., etc. in front of noun(s) and the like may be used herein to describe various elements, these elements should not be limitedby these terms. These terms are only used to distinguish one element from another and they do not limit the order of the noun(s). 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.

[0034] 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.

[0035] 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.

[0036] 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.

[0037] 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 ci rcuit(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.

[0038] 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 for a mobile device or a similar integrated circuit in server, a cellular network device, or other computing or network device.

[0039] 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 (1 G), the second generation (2G), 2.5G, 2.75G, the third generation (3G), the fourth generation (4G), 4.5G, the fifth generation (5G), 5.5G, 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.

[0040] As used herein, the term “network device” refers to a node in a communication network via which a terminal device accesses the network and receives services therefrom. The network device may refer to 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 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) 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 comprises a Centralized Unit (CU) and a Distributed Unit (DU) at an IAB donor node. An IAB node comprises 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 next-hop IAB node.

[0041] The term “terminal device” refers to any end device that may be capable of wirelesscommunication. By way of example rather than limitation, a terminal device may also be referred to as a communication device, user equipment (UE), a Subscriber Station (SS), a Portable Subscriber Station, a Mobile Station (MS), or an Access Terminal (AT). The terminal 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 terminal 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 “terminal device”, “communication device”, “terminal”, “user equipment” and “UE” may be used interchangeably.

[0042] As used herein, the term “resource,” “transmission resource,” “resource block,” “physical resource block” (PRB), “uplink resource,” or “downlink resource” may refer to any resource for performing a communication, for example, a communication between a terminal device and a network device, 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 combination of the time, frequency, space and / or code domain 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.

[0043] Currently, CSI feedback from the UE and several forms of reference signal (RS) transmissions in downlink (DL) and uplink (UL) are happening when the UE is in a radio resource control (RRC) connected mode (also referred to as a RRC connected state). This comes at the expense of increased latency because these procedures start after the UE turns into the RRC connected mode, thus valuable time is lost until RS signals are transmitted and measured, and CSI feedback is available for efficient link adaptation.

[0044] In other words, it has been identified that there is a unreasonable or significant latency when the UE is coming to the RRC connected state from idle or inactive state. Thus, an early configurationfor preparing, for example, SRS, CSI-RS, CSI feedback is desired for the UE to perform associated operations in advance, for example, to make timely transmission of these signals possible right after the UE transitions into the connected state.

[0045] In accordance with some example embodiments of the present disclosure, there is provided a solution for an early configuration message. In one solution, a terminal apparatus receives from a network apparatus, an early configuration message prior to starting a random access channel (RACH) procedure or transitioning to a RRC idle or inactive state and the early configuration message indicates at least one early configuration. The terminal apparatus further receives, from the network apparatus, a random access response (RAR) message comprising an indication associated with the at least one early configuration. Based on at least the indication, the terminal apparatus determines a target early configuration of the at least one early configuration.

[0046] With this solution, at least one early configuration may be indicated to the terminal apparatus prior to a RACH procedure or prior to the terminal apparatus transitioning into the RRC idle or inactive state, such that the terminal apparatus can perform operations such as CSI measurements corresponding to the early configuration(s) in advance.

[0047] Example embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings.

[0048] Reference is first made to FIG. 1 . FIG. 1 shows an example communication environment 100 in which example embodiments of the present disclosure may be implemented. The network communication 100 comprises one or more terminal apparatuses, such as a terminal apparatus 110, and one or more network apparatuses such as a network apparatus 120. Although illustrated as a base station, the network apparatus 120 may be or may be comprised in any other suitable network device. Although illustrated as a UE, the terminal apparatus 110 may be or may be comprised in any other suitable terminal device.

[0049] In some example embodiments, a communication direction from the network apparatus 120 to the terminal apparatus 110 is referred to as a downlink (DL), and a communication direction from the terminal apparatus 110 to the network apparatus 120 is referred to as an uplink (UL). In DL, the network apparatus 120 is a transmitting (TX) apparatus (or a transmitter) and the terminal apparatus 110 is a receiving (RX) apparatus (or a receiver). In UL, the terminal apparatus 110 is a TX apparatus (or a transmitter) and the network apparatus 120 is a RX apparatus (or a receiver).

[0050] Communications in the communication environment 100 may be implemented according to any proper communication protocol (s), comprising, but not limited to, cellular communication protocols,wireless local network communication protocols such as Institute for Electrical and Electronics Engineers (IEEE) 802.11 and the like, and / or any other protocols currently known or to be developed in the future. Moreover, the communication may utilize any proper wireless communication technology, comprising but not limited to: Code Division Multiple Access (CDMA), Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA), Frequency Division Duplex (FDD), Time Division Duplex (TDD), Multiple-Input Multiple-Output (MIMO), Orthogonal Frequency Division Multiple (OFDM), Discrete Fourier Transform spread OFDM (DFT-s-OFDM) and / or any other technologies currently known or to be developed in the future.

[0051] In the following, for the purpose of illustration, some example embodiments may be described with the terminal apparatus 110 operating as a terminal device. However, in some example embodiments, operations described in connection with a terminal device may be implemented at a network device or other device, and operations described in connection with a network device may be implemented at a terminal device or other device.

[0052] It is to be understood that the number of apparatuses and their connections shown in FIG. 1 are only for the purpose of illustration without suggesting any limitation. The communication environment 100 may include any suitable number of apparatuses configured to implement example embodiments of the present disclosure. Although not shown, it would be appreciated that one or more additional apparatuses may be deployed in the communication environment 100.

[0053] FIG. 2A illustrates a signaling flow of an example process 200 for an early configuration message in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the process 200 will be described below with reference to the terminal apparatus 110 and network apparatus 120 in FIG. 1.

[0054] As illustrated in FIG. 2A, in the process 200, the network apparatus 120 transmits 222, to the terminal apparatus 110, an early configuration message indicating at least one early configuration. The terminal apparatus 110 receives 224 the early configuration message prior to starting a random access channel (RACH) procedure or transitioning to a radio resource control (RRC) idle or inactive state.

[0055] In some embodiments, the early configuration(s) indicated in the early configuration may comprise one or more sounding reference signal (SRS) configurations, one or more channel state information (CSI) reference signal (RS) configurations and / or one or more CSI report configurations. Thus, an early SRS transmission, CSI-RS transmission and measurement and / or CSI acquisition and reporting may be configured in the early configuration message in advance.

[0056] In some embodiments, the early configuration message may comprise a SIB message indicating at least one early configuration. The terminal apparatus 110 may receive the SIB message prior to a RACH procedure. The SIB message may be any suitable SIB message defined based on a SIB message in 3GPP specification. For example, the SIB message indicating the early configuration(s) may be defined based on the existing SIB11 , SIB12 or SIB13. In the following, the newly defined SIB message indicating the early configuration(s) may be referred to as early SIB message, SIB message or SIBx message for short.

[0057] In some examples, an early SRS transmission configuration (e.g., parametrization) may be provided to the terminal apparatus based on the indication of one or more SIB messages for an SRS transmission (also referred to as the SRS SIB message, e.g., denoted as SIB1 Ox). The SRS SIB message may include one or more early SRS configurations. The early SRS configuration may provide support for any suitable SRS functionality, and the scope of the present disclosure is not limited in this regard.

[0058] In some examples, the early SRS configuration may include at least one of the following SRS functionalities: UL SRS resources with usage codebook without frequency hopping (no full or partial hopping); UL SRS with UL PC by using SSB as pathloss reference and enabling network to configure with limited set of power control parameters; or UL SRS resource support the following options: 1) comb-2, comb-4 and comb-8 and related cyclic-shift values, 2) transmission occasion in any place within slot from symbol index 0 to 13, 3) repetition factors of 1 , 2, 4, 5, 6, 7, 8, 10, 12, 14, 4) comboffset hopping for interference randomization for comb-4 and comb-8, or 5) restricted set of periodicities and slots offset.

[0059] One example implementation of the SIB1 Ox including configuration of UL SRS resources for idle / inactive UEs is shown as follows:- ASN1 START- TAG-SIB1 OX-START SIB10X-6G ::=-void text — SRS-ResourceSet ::= sequence { srs-ResourceSetld 0 srs-ResourceldList SEQUENCE (SIZE(1..maxNrofSRS-ResourcesPerSet)) OF SRS-Resourceld usage ENUMERATED { codebook } pO INTEGER (-202..24) pathlossReferenceRS SSB-lndex } SRS-ResourceSet ::= sequence { srs-ResourceSetld 1 usage ENUMERATED { antennaSwitching } pO INTEGER (-202..24) pathlossReferenceRS SSB-lndex } SRS-Resource ::= SEQUENCE { srs-Resourceld SRS-Resourceld nrofSRS-Ports ENUMERATED {portl , ports2 , ports4},transmissionComb CHOICE { n2 SEQUENCE { combOffset-n2 INTEGER (0..1), cyclicShift-n2 INTEGER (0..7) }. n4 SEQUENCE ! combOffset-n4 INTEGER (0..3), cyclicShift-n4 INTEGER (0..11) }N8 SEQUENCE ! combOffset-n8 INTEGER (0..7), cyclicShift-n8 INTEGER (0...5) }}. resourceMapping SEQUENCE { startPosition INTEGER (0..13), nrofSymbols ENUMERATED {n1 , n2, n4, n8, n10, n12, n14}, repetitionFactor ENUMERATED {n1 , n2, n4, n5, n6, n7, n8, n10, n12, n14} }, } freqDomainPosition INTEGER (0..67), freqDomainShift INTEGER (0..268), sequenceld INTEGER (0..1023),SRS-SpatialRelationlnfo ::= SEQUENCE { referencesignal ssb-lndex SSB-lndex, combOffsetHopping SEQUENCE { hoppingid INTEGER (0..1023) OPTIONAL, - Need R hoppingSubset CHOICE { transmissionComb-n4 BIT STRING (SIZE (4)), transmissionComb-n8 BIT STRING (SIZE (8))} hoppingWithRepetition ENUMERATED {symbol, repetition} OPTIONAL -- Need R }SRS-PeriodicityAndOffset ::= CHOICE { sl10 INTEGER(0..9), sl40 INTEGER(0..39), sl80 INTEGER(0..79),SI160 INTEGER(0..159),SI320 INTEGER(0..319),SI640 INTEGER(0..639),SI1280 INTEGER(0..1279), SI2560 INTEGER(0..2559) }}--void text —- ASN1 STOP- TAG-SIB1 OX-STOP

[0060] In some examples, an early CSI-RS transmission configuration (e.g., parametrization) may be provided to the terminal apparatus based on the indication of one or more SIB messages for a CSI- RS configuration (also referred to as the CSI-RS SIB message, e.g., denoted as SI B20x). The CSI- RS SIB message may include one or more early CSI-RS configurations. The early CSI-RS configuration may provide support for any suitable CSI-RS functionality, and the scope of the present disclosure is not limited in this regard.

[0061] In some examples, the early CSI-RS configuration may include CSI-RS functionalities such as CSI-RS resources with 1 ) one port; no CDM; density 3 (to be used for initial high qualitymeasurement in case of initial new cell operation), 2) one port; no CDM; density 0.5 (to be used when a previous connected mode has a potential indication of the channel state quality); 3) two port; density 1 , FD-CDM2; 4) four port; density 1 , FD-CDM2; 5) eight port; density 1 , CDM4; 6) 12, 16, 24, 32 port, density 1 .

[0062] Alternatively or additionally, the early CSI-RS configuration may include CSI-RS functionalities such as that quasi co-location (QCL) information is the follow-QCL of the SSB to which the UE is attached. Alternatively or additionally, the CSI-RS SIB message may contain information related to the frequency domain allocation and first OFDM symbol in time domain, and the time / frequency resources needed to estimate the CSI-RS.

[0063] In some examples, an early CSI report configuration (e.g., parametrization) may be provided to the terminal apparatus based on the indication of one or more SIB messages for CSI reporting (also referred to as CSI report SIB message, e.g., denoted as SI B30x). The SIB message for CSI reporting may include one or more early CSI report configurations. The early CSI report configuration may provide support for any suitable CSI report functionality, and the scope of the present disclosure is not limited in this regard. For example, the S I B30x may provide support for existing CSI-ReportConfig, CSI-ResourceConfig, and / or CSI-AperiodicTriggerStateList where selected resources for UL reporting are provided.

[0064] Alternatively or additionally to the SIB message, the early configuration message may comprise a RRC release message and / or a RRC suspend message. The terminal apparatus 110 may receive the RRC release message prior to transitioning into a RRC idle state or receive the RRC suspend message prior to transitioning into a RRC inactive state.

[0065] In the RRC idle state, no transmission may be possible from the UE side. In the RRC connected state, an RRC connection may be established and RRC signaling is possible to the UE. In the RRC inactive state, UE may be in a sleep mode and monitor periodically paging messages. The UE may be unable to have data transmission, except for performing a physical random access channel (PRACH) transmission when trying to transition from the inactive to connected states (i.e., RRCResumeRequest). The UE may perform a 4-step or 2-step RACH procedure to transition into the RRC connected state. Details will be described with reference to FIG. 3 in the following specification.

[0066] With continued reference to FIG. 2A, based on the early configuration message (e.g., a SIB message or RRC release / suspend message) indicating the early configuration(s), the terminal apparatus 110 may perform operation(s) corresponding to the early configuration(s). For example, if the early configuration(s) comprise a CSI-RS configuration and / or a CSI report configuration, theterminal apparatus 110 may perform a CSI measurement and / or CSI calculation based on the CSI-RS configuration and / or the CSI report configuration. In some cases, the terminal apparatus 110 may perform the operations corresponding to the early configuration(s) indicated by the early configuration message without waiting for any further indication for the early configurations.

[0067] As illustrated in FIG. 2A, the network apparatus 120 further determines 226 a target early configuration of the early configurations for the terminal apparatus 110. Note that, the target early configuration may comprise one or more early configurations such as an SRS configuration, a CSI- RS configuration, or a CSI report configuration.

[0068] The network apparatus 120 transmits 228 a RAR message comprising an indication associated with the target early configuration to the terminal apparatus 110. The terminal apparatus 110 receives 230 the RAR message and determines 232 the target early configuration of the at least one early configuration based on the indication in the RAR message.

[0069] The target early configuration may be a selected early configuration of the early configurations indicated by the early configuration message and it may be indicated to the terminal apparatus 110 based on the RAR message. For example, the SIB message may include a plurality of early configurations, and a target early configuration of the plurality of early configurations may be indicated to the terminal apparatus 110 based on the RAR message. In this way, the cell-specific SIB message can be converted into a UE-specific configuration.

[0070] In some embodiments, the terminal apparatus 110 may perform the operation corresponding to the target early configuration until it determines the target early configuration, without performing any operation corresponding to other configuration(s) indicated by the early configuration message. Alternatively, as discussed above, the terminal apparatus 110 may perform the operations corresponding to various early configurations in the early configurations before it receives the RAR message or before it determines the target early configuration, but the terminal apparatus 110 may only proceed with the operation corresponding to the target early configuration after it determines the target early configuration. For example, the terminal apparatus 110 may perform more than one CSI measurements corresponding the more than one CSI-RS configurations in the early configuration message, but only use one CSI measurement corresponding to the target CSI-RS configuration for later CSI reporting.

[0071] The indication associated with the at least one early configuration may be indicated by one or more bits in the RAR message. The one or more bits may comprise a CSI request bit, a bit in a physical uplink shared channel (PUSCH) frequency resource allocation field, and / or one or morerepurposed bits in the RAR message. As an example, in the RAR message defined in 3GPP TS 38.213, a CSI request bit is reserved. The CSI request bit may be used for indicating the target early configuration of the at least one early configurations indicated by the early configuration message. As another example, one or more bits in the PUSCH frequency resource field (which may have e.g., 14 bits) may be used for indicating the target early configuration. As another example, any other suitable bit(s) in the RAR message may be repurposed for indicating the target early configuration. That is, the bit(s) may be defined or configured initially for a different purpose and may be reused / repurposed for indicating the target early configuration.

[0072] In some embodiments, the terminal apparatus 110 may determine, based on the CSI request bit, a part of the PUSCH frequency resource allocation field, and determine based on the part of the PUSCH frequency resource allocation field, the target early configuration of the at least one early configuration. In other words, the CSI request bit may be used for changing the interpretation of the PUSCH frequency source allocation field, i.e., reinterpretation of the bits in the RAR message may be achieved for indicating the target early configuration. Alternatively or additionally, the terminal apparatus 110 may determine, based on the one or more repurposed bits in the RAR, the target early configuration of the at least one early configuration.

[0073] As an example, 14 bits of the PUSCH frequency source allocation field may be split such that half of them, 7 bits, are used for indicating the target early configuration. The target early configuration may include one or more of an SRS configuration, a CSI-RS configuration, or a CSI report configuration.

[0074] In some examples, it is understood that the 7 bits are creating 128 states which may be used to represent various early configurations of SRS, CSI-RS and / or CSI reporting. Without loss of generality, among multiple SIBx configurations for SRS, CSI-RS, CSI feedback, the UE may be configured with one SIBx configuration for an SRS transmission and / or one SIBx for a CSI-RS transmission and / or one SIBx for CSI feedback reporting. The one or more SIBx configurations may be indicated by the 7 bits of the PUSCH frequency source allocation field or one or more repurposed bits in the RAR message. Thus, based on the RAR message, the cell specific nature of SIBs (i.e., the SIB configuration may be configured to multiple UEs) may be converted into UE specific nature of SIBs.

[0075] In some embodiments, the at least one early configuration (and the target early configuration) may comprise a previous configuration used for the terminal apparatus 110 in a previous RRC connected state or a reference configuration indicating the previous configuration. That is, SRS, CSI- RS and / or CSI configurations used before the UE went to the idle or inactive state may be re-configured in the early configuration message. For example, the SIBx message may contain a CSI- RS configuration which has been used by the UEs during the previous RRC connected mode. If such SIBx message is discovered by the UEs prior to starting the RACH procedure, measurements of such CSI-RS and CSI feedback computation may commence prior to the RACH procedure. Thus, in acknowledgement (e.g., a hybrid automatic repeat request (HARQ)-ACK) of a message 4 in the RACH procedure, the UE may already have CSI feedback to transmit to the gNB. Details of reusing the previous configuration will be described below with reference to FIG. 2B.

[0076] FIG. 2B illustrates a signaling flow of another example process 250 for an early configuration message in accordance with some example embodiments of the present disclosure. The process 250 may be deemed as a detailed example of the process 200 in FIG. 2A. Specifically, the process 250 relates to reusing the previous configuration indicated in the early configuration message. For the purpose of simplicity, detailed description of operations corresponding to the operations in FIG. 2A may be omitted.

[0077] As illustrated in FIG. 2B, similar to FIG. 2A, the network apparatus 120 transmits 252 an early configuration message to the terminal apparatus 110. The terminal apparatus 110 receives 254 the early configuration message. The network apparatus 120 further transmits 258 a RAR message to the terminal apparatus 110. The terminal apparatus 110 receives 260 the RAR message and determines 262 a target early configuration based on the indication in the RAR message.

[0078] Note that, in FIG. 2B, the early configuration message indicates at least one early configuration comprising a previous configuration used for the terminal apparatus 110 in a previous RRC connected state or a reference configuration indicating the previous configuration. The reference configuration may be used for differentially identifying / reusing the previous configuration.

[0079] The terminal apparatus 110 may store information associated with the previous configuration to further facilitate the reusing of the previous configuration. The information associated with the previous configuration may comprise the previous configuration itself, e.g., previous parameterization of the previous configuration. Alternatively or additionally, the information associated with the previous configuration may comprise information used in association with the previous configuration. For example, in a case where the previous configuration is a CSI report configuration, the information associated with the previous configuration may comprise one or more of a CSI measurement, a reference signal configuration used for a CSI measurement, a CSI report quantity (parameter), or CSI calculation information (including, e.g., a calculation algorithm or calculations related to channel estimation filter construction like Wiener filter weights). Depending on the early configuration message, the information associated with the previous configuration may be stored at different moments.

[0080] In some examples, the early configuration message indicating the early config u ration (s) comprising the previous configuration may be a RRC release message or a RRC suspend message. In response to receiving the RRC release or suspend message, the terminal apparatus 110 may determine to store 256 the information associated with the previous configuration in the RRC idle or inactive state in the previous RRC connected state. That is, contrary to flushing the information of the previously used configuration when transitioning from the RRC connected state to the idle or inactive state, the terminal apparatus 110 may continue storing the information in the idle or inactive state. For example, the terminal apparatus 110 may keep buffering the information in a memory. The terminal apparatus 110 may store the information associated with the previous configuration in any suitable manner, and the scope of the present disclosure is not limited in this regard. It will be appreciated that throughout the specification, the term “buffer” and derivations therefrom when used in conjunction with information are to be understood to mean “store” or “keep” and corresponding derivations therefrom.

[0081] In some embodiments, the early configuration message indicating the early configuration(s) comprising the previous configuration may be a SIB message. The terminal apparatus 110 may receive the SIB message in a RRC idle / inactive state prior to starting a RACH procedure. In this case, the previous configuration may be the configuration used in a previous RRC connected state prior to the RRC idle / inactive state where the SIB message is received, and the terminal apparatus 110 may determine to store 257 the information after transitioning from the previous RRC connected state to the RRC idle or inactive state where the SIB message is received. For example, in response to receiving a RRC release / suspend message in the previous RRC connected state, the terminal apparatus 110 may determine to keep buffering the information in the memory. Details of the buffering of the information associated the previous configuration will be described below with reference to FIG. 2C.

[0082] FIG. 2C illustrates a signaling flow of an example process 280 for buffering information associated with a previous configuration in accordance with some example embodiments of the present disclosure. As illustrated in FIG. 2C, the process 280 involves a UE 281 and a gNB 282. The UE 281 may be an example of the terminal apparatus 110 in FIG. 1 and the gNB 282 may be an example of the network apparatus 120 in FIG. 1.

[0083] In the process 280, at TO, the UE 281 is in a previous RRC connected state and is configured with CSI measurement and CSI feedback through different or same (higher and lower layer) configurations. At T1 , the UE 281 receives a RRC release (with suspend) message and transitions into the RRC idle / inactive state.

[0084] Between TO and T1 , the gNB 282 may write 285, i.e., include the previous configuration usedby the UE 281 in a SIBx message(s). At T1 , the UE 281 receives the RRC release / suspend message and at T2 the UE 281 buffers / keeps in its memory, information associated with the previous configuration, e.g., the previous parametrization of the previous CSI-RS configuration, previous SRS configuration, and / or previous CSI reporting configuration. The UE 281 may buffer also various quantities it used for the measurement and calculation of the CSI feedback, such as calculations related to channel estimation filter construction like Wiener filter weights.

[0085] At T3, the UE 281 receives a RRC resume message and starts a RACH procedure. Prior to transmitting a Message 1 to the UE 281 , the gNB 282 may transmit 287 the SIBx message(s) indicating at least the previous configuration. The UE 281 receives 289 the SIBx message(s) as the early configuration message(s). At T4, the RACH procedure is successful and the UE 281 transitions to a RRC connected state again. Between TO and T4, the UE 281 stores the buffered information described above in the memory despite the RRC release / suspend signaling received when the UE 281 is not required to perform other types of measurements. In other words, although the UE 281 may not perform other operations in the idle / inactive state, the UE 281 may store the information associated with the previous configuration and may perform operations corresponding to the previous configuration before it transitions to the RRC connected state.

[0086] As another example, the UE in the previous RRC connected state may have computed a form of CSI based on RRC and DCI signaling, then it transitions to the idle / inactive state. The form of the CSI and / or previous information which led to the previous CSI computation may be stored in the idle / inactive state, such that they can be reused for a fresh CSI computation when the UE transitions back to a RRC connected state.

[0087] Referring back to FIG. 2B, in some embodiments, the terminal apparatus 110 may receive at least a portion of the stored information from the network apparatus 120, e.g., in the previous RRC connected state. The stored information associated with the previous configuration may comprise a portion received from the network apparatus 120 and a portion determined based on implementation of the terminal apparatus 110. For example, the stored CSI measurement may be determined by the terminal apparatus 110 and may not be received from the network apparatus 120.

[0088] In some embodiments, the terminal apparatus 110 may reuse the information associated with the previous configuration after determining, based on the indication in the RAR message, that the previous configuration is at least a portion of the target early configuration. That is, after determining the target early configuration indicated by the RAR message, the terminal apparatus 110 may reuse the stored information associated with the previous information.

[0089] In some embodiments, the terminal apparatus 110 may reuse the information associated with the previous configuration prior to starting the RACH procedure. For example, if the information is stored since the previous RRC connected state and the UE receives the SIB message prior to starting the RACH, the UE may reuse the information associated with the previous configuration to perform the operation based on the previous configuration, e.g., performing CSI calculation based on the stored CSI measurements.

[0090] Alternatively, the terminal apparatus 110 may reuse the information associated with the previous configuration after transitioning to a RRC connected state. For example, the UE may keep buffering the information associated with the previous configuration and reuse it after the UE transitions to a new RRC connected state.

[0091] In some embodiments, in response to receiving the early configuration message indicating at least the previous configuration, the terminal apparatus 110 may determine whether the information associated with the previous configuration is stored in the terminal apparatus, i.e., determine whether related information has been stored. In accordance with a determination that the information associated with the previous configuration is stored in the terminal apparatus, the terminal apparatus 110 may determine to perform an operation based on the previous configuration by reusing the information associated with the previous configuration.

[0092] For example, when receiving the SIB message indicating the previous configuration, the terminal apparatus 110 may determine whether there is a match between the stored information and previous configuration. If it is determined that there is stored information that can be used in association with the previous configuration, the terminal apparatus 110 may perform an operation corresponding to the previous configuration by reusing the stored information. In this way, the match procedure can achieve an implicit signaling of triggering the performance of the previous configuration.

[0093] With reference to the above FIGS. 2A, 2B and 2C, solutions for the early configuration message according to the embodiments of the present disclosure are described. In the processes 200, 250 and 280, the early config u ration (s) may be indicated to the terminal apparatus 110 prior to a RACH procedure or prior to the terminal apparatus 110 transitioning into the RRC idle or inactive state, such that the terminal apparatus 110 can perform operations such as CSI measurements corresponding to the early configuration(s) in advance. Particularly, the terminal apparatus 110 can perform operations corresponding to the previous configuration based on the stored information associated with the previous configuration.

[0094] FIG. 3 illustrates a signaling flow of an example process 300 for an early configuration ofchannel state information (CSI) feedback in accordance with some example embodiments of the present disclosure. The process 300 may be deemed as a detailed example of the process 200, 250 or 280. As illustrated in FIG. 3, the process 300 involves a UE 310 and a gNB 320. The UE 310 may be an example of the terminal apparatus 110 in FIG. 1 and the gNB 320 may be an example of the network apparatus 120 in FIG. 1.

[0095] In the process 300, the gNB 320 may transmit 352 a synchronization signal block(SSB) / physical broadcast channel (PBCH) to the UE 310. The UE 310 receives 354 the SSB / PBCH. The gNB 320 may transmit 356 a SIB message to the UE 310 prior to a RACH procedure being initiated from the UE 310. The UE 310 receives 358 the SIB message. The SIB message may comprise a SIB1 configuration and / or a SIBx configuration for different configurations of SRS, CSI-RS and CSI.

[0096] Based on receiving 358 the SIB message, the UE 310 may perform 359 CSI measurements as indicated by the SIBx configuration prior to starting a RACH procedure. For example, the UE 310 may perform the CSI measurements by reusing the stored information associated with the previous configuration.

[0097] When starting a RACH procedure, the UE 310 may transmit a random access preamble (also referred to as message 1 or Msg1) to the gNB 320. The gNB 320 receives 362 the Msg1 and may determine, for the UE 310, a target early configuration of the early configuration(s) indicated in the SIB message. The gNB 320 may use a RAR message to indicate the target early configuration. The gNB 320 may perform 364 reinterpretation of bits in the RAR message to use one or more bits to indicate the target early configuration of the early configuration(s) indicated in the SIB message. Then the gNB 320 may transmit 366 the RAR message (also referred to as message 2 or Msg2) to the UE 310. The UE 310 receives 368 the RAR message and may determine the target early configuration based on the RAR message.

[0098] The RAR message may further comprise timing advance information as well as UL grant information, and based on this information the UE 310 may transmit 370 a scheduled transmission (also referred to as message 3 or Msg3) to the gNB 320. In some examples, the UE 310 may transmit 373 CSI feedback to the gNB 320 in the Msg3, such that the CSI feedback may be performed before the UE 310 transitions to the RRC connected state.

[0099] The gNB 320 receives 372 the scheduled transmission and may transmit 374 a contention resolution (also referred to as message 4 or Msg4) to the UE 310. The UE 310 may receive 376 the contention resolution and determine that the RACH procedure is successful. In some examples, afterthe UE 310 transitions to the RRC connected state, the UE 310 may transmit 378 the CSI feedback to the gNB 320 in a UL transmission based on the SIBx configuration and a follow-up indication. On the network side, the gNB 320 receives 380 the UE CSI feedback.

[0100] The follow-up indication may be the indication in the RAR message that identifies the target early configuration. For example, the UE 310 may select the performed CSI measurement corresponding to the target early configuration for CSI feedback. Alternatively or additionally, the follow-up indication may be a physical uplink control channel (PUCCH) resource or PUSCH resource to carry the CSI feedback report, and this indication may be indicted by the downlink control information (DCI) scheduling a physical downlink shared channel (PDSCH) for the Msg4 of the RACH procedure.

[0101] In some embodiments, before completion of a RACH procedure, the terminal apparatus 110 may further transmit, to the network apparatus 120, the UE’s capability information associated with the at least one early configuration. In some embodiments, the RAR message may comprise a request for the capability information. In this case, the terminal apparatus 110 may transmit the capability information in the Msg3 as a response to the request in the RAR message.

[0102] In some examples, the RAR message may carry request information to request the UE to indicate in Msg3 whether it has CSI report to be provided to the network and / or they are capable of performing SRS sounding or an SRS transmission.

[0103] In a case where the UE indicates in the Msg3 that it has a CSI report to be provided to the network, the network may indicate the UE PUCCH resource or PUSCH resources that it can carry both Msg4-HARQ-ACK and the CSI report. The indication may be in the DCI that schedules the PDSCH carrying the Msg4 to the UE. As an example, in the examples of FIG. 3, the UE 310 may transmit, in the Msg3, the capability information indicating a CSI report to be provided to the gNB 320.

[0104] As another example (not shown in FIG. 3), the terminal apparatus 110 may transmit, to the network apparatus 120, in the Msg3, the UE’s capability information indicating an early SRS transmission. For example, the UE may indicate in the Msg3 that it is capable of SRS sounding / transmission, the network may trigger an SRS transmission according to one transmission configuration in the SIBx message. Upon receiving the SRS trigger in the DCI scheduling the PDSCH carrying the Msg4, the UE may transmit, according to the SRS trigger, the SRS transmission (according to the configuration in SIBx).

[0105] Details of the capability information request and response will be described below with reference to FIG. 4 and FIG. 5.

[0106] FIG. 4 illustrates a flowchart of an example process 400 for an early configuration of CSI reporting in accordance with some example embodiments of the present disclosure. The process 400 may relate to CSI reporting based on the early configuration as part of a RACH procedure. For the purpose of discussion, the process 400 may be performed by the terminal apparatus 110 in FIG. 1. The process 400 may be deemed as a detailed example of the process 200, 250 or 280 in FIG. 2A, 2B or 2C.

[0107] As illustrated in FIG. 4, at block 410, the terminal apparatus 110 may perform CSI measurements based on a CSI measurement configuration in a SIB message. The terminal apparatus 110 may receive the SIB message from the network prior to a RACH procedure. The SIB message may indicate a previous configuration that is used by the terminal apparatus 110 in a previous RRC connected state and the information associated with the previous configuration may be stored in the terminal apparatus 110. The terminal apparatus 110 may store the associated information in the previous RRC connected state and keep the associated information even after transitioning from the previous RRC connected state to an idle / inactive state. The terminal apparatus 110 may further receive DL reference signals from the gNB, such as an SSB, tracking reference signal (TRS), CSI-RS.

[0108] Prior to performing the RACH procedure, the terminal apparatus 110 may use the stored SIB information associated with the previous configuration for CSI measurements / computation. As an example, the terminal apparatus 110 may perform channel measurements as indicated by the previous CSI-RS configuration. As another example, the terminal apparatus 110 may compute CSI feedback in terms of layer 1 (L1) reference signal received power (L1-RSRP), L1 -signal to interference plus noise ratio (SINR), rank indicator (Rl), channel quality indicator (CQI), precoding matrix indicator (PMI), and / or layer Indicator (LI).

[0109] At block 420, the terminal apparatus 110 may initiate a RACH procedure and receive a RAR message including a request for the terminal apparatus 110 to indicate in a Msg3 whether it has a CSI report to be sent. In other words, the RAR message may further indicate a request for capability information of CSI reporting based on the early configuration. This indication may be indicated by one or more bits in the RAR, for example, the CSI request bit.

[0110] At block 430, the terminal apparatus 110 may indicate in the Msg3 that it has a CSI report to be sent. At block 440, the terminal apparatus 110 may receive a DCI scheduling a PDSCH for the Msg4 and the DCI may indicate a PUCCH or PUSCH resource for the terminal apparatus 110 to send acknowledgement of the Msg4 and the CSI report. That is, the terminal apparatus 110 may transmit the CSI feedback on the UL resource as indicated by the DCI in an upcoming UL transmission.

[0111] FIG. 5 illustrates a flowchart of an example process 500 for an early configuration of a sounding reference signal (SRS) transmission in accordance with some example embodiments of the present disclosure. The process 500 may relate to an SRS transmission based on the early configuration as part of a RACH procedure. For the purpose of discussion, the process 500 may be performed by the terminal apparatus 110 in FIG. 1. The process 500 may be deemed as a detailed example of the process 200 or 250in FIG. 2A or 2B.

[0112] As illustrated in FIG. 5, at block 510, the terminal apparatus 110 may receive a SIBx message from the network, and the SIBx message comprises at least a previous SRS configuration. Similarly to FIG. 4, information associated with the previous SRS configuration (also referred to as SIBx information) may be stored in the terminal apparatus 110 from a previous RRC connected state where such associated SIBx information was used. The SIBx information may contain the previous configuration transmitted to the terminal apparatus 110, e.g., detailed parametrization for transmitting an SRS.

[0113] At block 520, the terminal apparatus 110 may initiate a RACH procedure and receive a RAR message including a request for the terminal apparatus 110 to indicate in a Msg3 whether it is capable of performing an early SRS transmission. In other words, the RAR message may further indicate a request for the UE’s capability information regarding an SRS transmission based on the early configuration. This indication may be indicated by one or more bits in the RAR, for example, the CSI request bit.

[0114] At block 530, the terminal apparatus 110 may indicate in the Msg3 that it can transmit an SRS as part of the RACH procedure. The terminal apparatus 110 may also indicate a candidate SRS configuration and / or a resource needed for the early SRS transmission. The candidate SRS configuration may be one or more SRS configurations indicated by the SIBx message or one or more SRS configurations of the target early configuration indicated by the RAR message. For example, the terminal apparatus 110 may transmit the SRS configuration which may be used and needed resources to fulfil the requested SRS transmission, such as one port transmission, and the needed number of antenna switches, etc.

[0115] At block 540, the terminal apparatus 110 may receive a DCI scheduling a PDSCH for Msg4 and the DCI triggers the terminal apparatus 110 to transmit an SRS according to the certain SRS configuration indicated by the DCI. For example, the DCI may indicate the certain SRS configuration of the candidate SRS configurations.

[0116] FIG. 6 shows a flowchart of an example method 600 implemented at a terminal apparatus inaccordance with some example embodiments of the present disclosure. For the purpose of discussion, the method 600 will be described from the perspective of the terminal apparatus 110 in FIG. 1.

[0117] At block 610, the terminal apparatus 110 receives, from a network apparatus, an early configuration message prior to starting a random access channel (RACH) procedure or transitioning to a radio resource control (RRC) idle or inactive state, the early configuration message indicating at least one early configuration.

[0118] At block 620, the terminal apparatus 110 receives, from the network apparatus, a random access response (RAR) message comprising an indication associated with the at least one early configuration.

[0119] At block 630, the terminal apparatus 110 determines, based on at least the indication, a target early configuration of the at least one early configuration.

[0120] In some example embodiments, the early configuration message comprises at least one of: a system information block (SIB) message, a RRC release message, or a RRC suspend message.

[0121] In some example embodiments, the target early configuration comprises at least one of: a sounding reference signal (SRS) configuration, a channel sate information (CSI) reference signal (RS)configuration, or a CSI report configuration.

[0122] In some example embodiments, the at least one early configuration comprises a previous configuration used for the terminal apparatus in a previous RRC connected state or a reference configuration indicating the previous configuration.

[0123] In some example embodiments, the method 600 further comprises: storing the previous configuration or the reference configuration after transitioning from the previous RRC connected state to a RRC idle or inactive state.

[0124] In some example embodiments, the indication associated with the at least one early configuration is indicated by one or more bits in the RAR message and the one or more bits comprise at least one of: a CSI request bit, a bit in a physical uplink shared channel (PUSCH) frequency resource allocation field, or one or more repurposed bits in the RAR message.

[0125] In some example embodiments, determining, based on the indication, the target early configuration of the at least one early configuration comprises: determining, based on the CSI request bit, a part of the PUSCH frequency resource allocation field; and determining, based on the part of the PUSCH frequency resource allocation field, the target early configuration of the at least one early configuration.

[0126] In some example embodiments, determining, based on the indication, the target early configuration of the at least one early configuration comprises: determining, based on the one or more repurposed bits in the RAR, the target early configuration of the at least one early configuration.

[0127] In some example embodiments, the method 600 further comprises: transmitting, to the network apparatus and before completion of a RACH procedure, capability information associated with the at least one early configuration.

[0128] In some example embodiments, the RAR message further comprises a request for the capability information.

[0129] In some example embodiments, transmitting to the network apparatus the capability information comprises: transmitting, in a message 3 of the RACH procedure, the capability information indicating a CSI report to be provided to the network apparatus.

[0130] In some example embodiments, the method 600 further comprises: receiving, from the network apparatus, downlink control information (DCI) indicating a PUCCH resource or a PUSCH resource for carrying the CSI report, the DCI scheduling a physical downlink shared channel (PDSCH) for a message 4 of the RACH procedure.

[0131] In some example embodiments, the method 600 further comprises: transmitting, to the network apparatus, the CSI report in acknowledgement of the message4.

[0132] In some example embodiments, the method 600 further comprises: performing a CSI-RS measurement based on the CSI-RS configuration prior to starting the RACH procedure, performing a CSI-RS measurement based on the CSI-RS configuration prior to receiving the RAR message in the RACH procedure, or performing a CSI-RS measurement based on the CSI-RS configuration after determining that the CSI-RS configuration is the target early configuration based on the indication in the RAR message.

[0133] In some example embodiments, transmitting to the network apparatus the capability information comprises: transmitting, in a message 3 of the RACH procedure, the capability information indicating an early SRS transmission.

[0134] In some example embodiments, the method 600 further comprises: receiving, from the network apparatus, downlink control information (DCI) indicating a trigger of transmitting a SRS, the DCI scheduling a PDSCH for a message 4 of the RACH procedure.

[0135] In some example embodiments, the method 600 further comprises: determining, from the at least one early configuration, an SRS configuration as the target early configuration based on theindication in the RAR message; and transmitting the SRS based on the SRS configuration to the network apparatus.

[0136] In some example embodiments, the method 600 further comprises: transmitting an SRS based on the SRS configuration to the network apparatus prior to starting the RACH procedure.

[0137] In some example embodiments, the early configuration message comprises a system information block (SIB) message indicating at least one of a CSI-RS configuration or a CSI report configuration, and the method 600 further comprises: performing at least one of a CSI measurement or CSI calculation based on the at least one of the CSI-RS configuration or the CSI report configuration prior to starting the RACH procedure or prior to receiving the RAR message in the RACH procedure.

[0138] In some example embodiments, the method 600 further comprises: determining, from the at least one of the CSI measurement or the CSI calculation, a CSI report based on the indication in the RAR message; and transmitting, in a messages of the RACH procedure, a CSI report based on the CSI report configuration and the CSI measurement.

[0139] FIG. 7 shows a flowchart of an example method 700 implemented at a network apparatus in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the method 700 will be described from the perspective of the network apparatus 120 in FIG. 1.

[0140] At block 710, the network apparatus 120 transmits an early configuration message to a terminal apparatus in a RRC connected state or transmits the early configuration message to the terminal apparatus prior to a random access channel (RACH) procedure being initiated from the terminal apparatus, the early configuration message indicating at least one early configuration.

[0141] At block 720, the network apparatus 120 determines, for the terminal apparatus, a target early configuration of the at least one early configuration.

[0142] At block 730, the network apparatus 120 transmits, to the terminal apparatus, a random access response (RAR) message comprising an indication associated with the target early configuration.

[0143] In some example embodiments, transmitting the early configuration message to the terminal apparatus in the RRC connected state comprises transmitting a RRC release message or a RRC suspend message to the terminal apparatus, and transmitting the early configuration message to the terminal apparatus prior to the random access channel (RACH) procedure being initiated from the terminal apparatus comprises transmitting a system information block (SIB) message to the terminal apparatus.

[0144] In some example embodiments, the target early configuration comprises at least one of: a sounding reference signal (SRS) configuration, a channel sate information (CSI) reference signal (RS)configuration, or a CSI report configuration.

[0145] In some example embodiments, the at least one early configuration comprises a previous configuration used for the terminal apparatus in a previous RRC connected state or a reference configuration indicating the previous configuration.

[0146] In some example embodiments, the method 700 further comprises: including the previous configuration or the reference configuration in the at least one early configuration.

[0147] In some example embodiments, the indication associated with the target early configuration is indicated by one or more bits in the RAR message and the one or more bits comprise at least one of: a CSI request bit, a bit in a physical uplink shared channel (PUSCH) frequency resource allocation field, or one or more repurposed bits in the RAR message.

[0148] In some example embodiments, the CSI request bit indicates a part of the PUSCH frequency resource allocation field indicating the target early configuration.

[0149] In some example embodiments, the method 700 further comprises: receiving, from the terminal apparatus and before completion of a RACH procedure, capability information associated with the at least one early configuration.

[0150] In some example embodiments, the RAR message further comprises a request for the capability information.

[0151] In some example embodiments, receiving from the terminal apparatus the capability information comprises: receiving, in a message 3 of the RACH procedure, the capability information indicating a CSI report to be provided to the network apparatus.

[0152] In some example embodiments, the method 700 further comprises: transmitting, to the terminal apparatus, downlink control information (DCI) indicating a PUCCH resource or a PUSCH resource for carrying the CSI report, the DCI scheduling a PDSCH for a message 4 of the RACH procedure.

[0153] In some example embodiments, the method 700 further comprises: receiving, from the terminal apparatus, the CSI report in acknowledgement of the message4.

[0154] In some example embodiments, receiving from the terminal apparatus the capability information comprises: receiving, in a message 3 of the RACH procedure, the capability information indicating an early SRS transmission.

[0155] In some example embodiments, the method 700 further comprises: transmitting, to the terminal apparatus, downlink control information (DCI) indicating a trigger of transmitting an SRS, the DCI scheduling a PDSCH for a message 4 of the RACH procedure.

[0156] In some example embodiments, the method 700 further comprises: receiving, from the terminal apparatus, the SRS transmitted based on an SRS configuration associated with the target early configuration.

[0157] In some example embodiments, the method 700 further comprises: receiving an SRS transmitted based on the SRS configuration from the terminal apparatus prior to the initiation of the RACH procedure.

[0158] In some example embodiments, the early configuration message comprises a system information block (SIB) message indicating at least one of a CSI-RS configuration or a CSI report configuration, and the method 700 further comprises: receiving, in a message 3 of a RACH procedure, a CSI report based on the at least one of the CSI-RS configuration or the CSI report configuration from the terminal apparatus.

[0159] In some example embodiments, a terminal apparatus capable of performing any of the method 600 (for example, the terminal apparatus 110 in FIG. 1) may comprise means for performing the respective operations of the method 600. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module. The terminal apparatus may be implemented as or included in the terminal apparatus 110 in FIG. 1 .

[0160] In some example embodiments, the terminal apparatus comprises means for receiving, from a network apparatus, an early configuration message prior to starting a random access channel (RACH) procedure or transitioning to a radio resource control (RRC) idle or inactive state, the early configuration message indicating at least one early configuration; means for receiving, from the network apparatus, a random access response (RAR) message comprising an indication associated with the at least one early configuration; and means for determining, based on at least the indication, a target early configuration of the at least one early configuration.

[0161] In some example embodiments, the early configuration message comprises at least one of: a system information block (SIB) message, a RRC release message, or a RRC suspend message.

[0162] In some example embodiments, the target early configuration comprises at least one of: a sounding reference signal (SRS) configuration, a channel state information (CSI) reference signal (RS) configuration, or a CSI report configuration.

[0163] In some example embodiments, the at least one early configuration comprises a previous configuration used by the terminal apparatus in a previous RRC connected state or a reference configuration indicating the previous configuration.

[0164] In some example embodiments, the terminal apparatus further comprises: means for storing the previous configuration or the reference configuration after transitioning from the previous RRC connected state to a RRC idle or inactive state.

[0165] In some example embodiments, the indication associated with the at least one early configuration is indicated by one or more bits in the RAR message and the one or more bits comprise at least one of: a CSI request bit, a bit in a physical uplink shared channel (PUSCH) frequency resource allocation field, or one or more repurposed bits in the RAR message.

[0166] In some example embodiments, the means for determining, based on the indication, the target early configuration of the at least one early configuration comprises: means for determining, based on the CSI request bit, a part of the PUSCH frequency resource allocation field; and means for determining, based on the part of the PUSCH frequency resource allocation field, the target early configuration of the at least one early configuration.

[0167] In some example embodiments, the means for determining, based on the indication, the target early configuration of the at least one early configuration comprises: means for determining, based on the one or more repurposed bits in the RAR, the target early configuration of the at least one early configuration.

[0168] In some example embodiments, the terminal apparatus further comprises: means for transmitting, to the network apparatus and before completion of a RACH procedure, capability information associated with the at least one early configuration.

[0169] In some example embodiments, the RAR message further comprises a request for the capability information.

[0170] In some example embodiments, the means for transmitting to the network apparatus the capability information comprises: means for transmitting, in a message 3 of the RACH procedure, the capability information indicating a CSI report to be provided to the network apparatus.

[0171] In some example embodiments, the terminal apparatus further comprises: means for receiving, from the network apparatus, downlink control information (DCI) indicating a PUCCH resource or a PUSCH resource for carrying the CSI report, the DCI scheduling a physical downlink shared channel (PDSCH) for a message 4 of the RACH procedure.

[0172] In some example embodiments, the terminal apparatus further comprises: means for transmitting, to the network apparatus, the CSI report in acknowledgement of the messaged

[0173] In some example embodiments, the terminal apparatus further comprises: means for performing a CSI-RS measurement based on the CSI-RS configuration prior to starting the RACH procedure, means for performing a CSI-RS measurement based on the CSI-RS configuration prior to receiving the RAR message in the RACH procedure, or means for performing a CSI-RS measurement based on the CSI-RS configuration after determining that the CSI-RS configuration is the target early configuration based on the indication in the RAR message.

[0174] In some example embodiments, the means for transmitting to the network apparatus the capability information comprises: means for transmitting, in a message 3 of the RACH procedure, the capability information indicating an early SRS transmission.

[0175] In some example embodiments, the terminal apparatus further comprises: means for receiving, from the network apparatus, downlink control information (DCI) indicating a trigger of transmitting a SRS, the DCI scheduling a PDSCH for a message 4 of the RACH procedure.

[0176] In some example embodiments, the terminal apparatus further comprises: means for determining, from the at least one early configuration, an SRS configuration as the target early configuration based on the indication in the RAR message; and means for transmitting the SRS based on the SRS configuration to the network apparatus.

[0177] In some example embodiments, the terminal apparatus further comprises: means for transmitting an SRS based on the SRS configuration to the network apparatus prior to starting the RACH procedure.

[0178] In some example embodiments, the early configuration message comprises a system information block (SIB) message indicating at least one of a CSI-RS configuration or a CSI report configuration, the terminal apparatus further comprises: means for performing at least one of a CSI measurement or CSI calculation based on the at least one of the CSI-RS configuration or the CSI report configuration prior to starting the RACH procedure or prior to receiving the RAR message in the RACH procedure.

[0179] In some example embodiments, the terminal apparatus further comprises: means for determining, from the at least one of the CSI measurement or the CSI calculation, a CSI report based on the indication in the RAR message; and transmitting, in a messages of the RACH procedure, a CSI report based on the CSI report configuration and the CSI measurement.

[0180] In some example embodiments, a network apparatus capable of performing any of the method 700 (for example, the network apparatus 120 in FIG. 1) may comprise means for performing the respective operations of the method 700. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module. The network apparatus may be implemented as or included in the network apparatus 120 in FIG. 1 .

[0181] In some example embodiments, the network apparatus comprises means for transmitting an early configuration message to a terminal apparatus in a RRC connected state or transmitting the early configuration message to the terminal apparatus prior to a random access channel (RACH) procedure being initiated from the terminal apparatus, the early configuration message indicating at least one early configuration; means for determining, for the terminal apparatus, a target early configuration of the at least one early configuration; and means for transmitting, to the terminal apparatus, a random access response (RAR) message comprising an indication associated with the target early configuration.

[0182] In some example embodiments, the means for transmitting the early configuration message to the terminal apparatus in the RRC connected state comprises means for transmitting a RRC release message or a RRC suspend message to the terminal apparatus, and the means for transmitting the early configuration message to the terminal apparatus prior to the random access channel (RACH) procedure being initiated from the terminal apparatus comprises means for transmitting a system information block (SIB) message to the terminal apparatus.

[0183] In some example embodiments, the target early configuration comprises at least one of: a sounding reference signal (SRS) configuration, a channel sate information (CSI) reference signal (RS)configuration, or a CSI report configuration.

[0184] In some example embodiments, the at least one early configuration comprises a previous configuration used for the terminal apparatus in a previous RRC connected state or a reference configuration indicating the previous configuration.

[0185] In some example embodiments, the network apparatus further comprises: means for including the previous configuration or the reference configuration in the at least one early configuration.

[0186] In some example embodiments, the indication associated with the target early configuration is indicated by one or more bits in the RAR message and the one or more bits comprise at least one of: a CSI request bit, a bit in a physical uplink shared channel (PUSCH) frequency resource allocation field, or one or more repurposed bits in the RAR message.

[0187] In some example embodiments, the CSI request bit indicates a part of the PUSCH frequency resource allocation field indicating the target early configuration.

[0188] In some example embodiments, the network apparatus further comprises: means for receiving, from the terminal apparatus and before completion of a RACH procedure, capability information associated with the at least one early configuration.

[0189] In some example embodiments, the RAR message further comprises a request for the capability information.

[0190] In some example embodiments, the means for receiving from the terminal apparatus the capability information comprises: means for receiving, in a message 3 of the RACH procedure, the capability information indicating a CSI report to be provided to the network apparatus.

[0191] In some example embodiments, the network apparatus further comprises: means for transmitting, to the terminal apparatus, downlink control information (DCI) indicating a PUCCH resource or a PUSCH resource for carrying the CSI report, the DCI scheduling a PDSCH for a message 4 of the RACH procedure.

[0192] In some example embodiments, the network apparatus further comprises: means for receiving, from the terminal apparatus, the CSI report in acknowledgement of the message4.

[0193] In some example embodiments, the means for receiving from the terminal apparatus the capability information comprises: means for receiving, in a message 3 of the RACH procedure, the capability information indicating an early SRS transmission.

[0194] In some example embodiments, the network apparatus further comprises: means for transmitting, to the terminal apparatus, downlink control information (DCI) indicating a trigger of transmitting an SRS, the DCI scheduling a PDSCH for a message 4 of the RACH procedure.

[0195] In some example embodiments, the network apparatus further comprises: means for receiving, from the terminal apparatus, the SRS transmitted based on an SRS configuration associated with the target early configuration.

[0196] In some example embodiments, the network apparatus further comprises: means for receiving an SRS transmitted based on the SRS configuration from the terminal apparatus prior to the initiation of the RACH procedure.

[0197] In some example embodiments, the early configuration message comprises a system information block (SIB) message indicating at least one of a CSI-RS configuration or a CSI report configuration, and the network apparatus further comprises: means for receiving, in a message 3 of aRACH procedure, a CSI report based on the at least one of the CSI-RS configuration or the CSI report configuration from the terminal apparatus.

[0198] FIG. 8 illustrates a flowchart of another method implemented at a terminal apparatus in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the method 800 will be described from the perspective of the terminal apparatus 110 in FIG. 1.

[0199] At block 810, the terminal apparatus 110 receives from a network apparatus, an early configuration message prior to starting a random access channel (RACH) procedure or transitioning to a radio resource control (RRC) idle or inactive state, the early configuration message indicating at least one early configuration comprising a previous configuration used by the terminal apparatus in a previous RRC connected state or a reference configuration indicating the previous configuration.

[0200] At block 820, the terminal apparatus 110 stores information associated with the previous configuration in the RRC idle or inactive state.

[0201] At block 830, the terminal apparatus 110 receives from the network apparatus, a random access response (RAR) message comprising an indication associated with the at least one early configuration.

[0202] At block 840, the terminal apparatus 110 determines based on at least the indication, a target early configuration of the at least one early configuration.

[0203] In some example embodiments, the early configuration message comprises at least one of: a system information block (SIB) message, a RRC release message, or a RRC suspend message.

[0204] In some example embodiments, the target early configuration comprises at least one of: a sounding reference signal (SRS) configuration, a channel state information (CSI) reference signal (RS) configuration, or a CSI report configuration.

[0205] In some example embodiments, the method 800 further comprises: reusing the information associated with the previous configuration prior to starting the RACH procedure, after transitioning to a RRC connected state, or after determining based on the indication that the previous configuration is at least a portion of the target early configuration.

[0206] In some example embodiments, reusing the information associated with the previous configuration prior to starting the RACH procedure or after transitioning to the RRC connected state comprises: in response to receiving the early configuration message, determining whether the information associated with the previous configuration is stored in the terminal apparatus; and in accordance with a determination that the information associated with the previous configuration isstored in the terminal apparatus, determining to perform an operation based on the previous configuration by reusing the information associated with the previous configuration.

[0207] In some example embodiments, the information associated with the previous configuration comprises at least one of: previous parametrization of the previous configuration, a CSI measurement, a reference signal configuration used for a CSI measurement, a CSI report quantity, or CSI calculation information.

[0208] In some example embodiments, the method 800 further comprises: receiving, from the network apparatus, at least a portion of the information associated with the previous configuration in the previous RRC connected state.

[0209] In some example embodiments, storing the information associated with the previous configuration in the RRC idle or inactive state comprises: in response to receiving a RRC release message or a RRC suspend message in the previous RRC connected state, determining to store the information associated with the previous configuration in the RRC idle or inactive state.

[0210] In some example embodiments, the indication associated with the at least one early configuration is indicated by one or more bits in the RAR message and the one or more bits comprise at least one of: a CSI request bit, a bit in a physical uplink shared channel (PUSCH) frequency resource allocation field, or one or more repurposed bits in the RAR message.

[0211] In some example embodiments, determining, based on the indication, the target early configuration of the at least one early configuration comprises: determining, based on the CSI request bit, a part of the PUSCH frequency resource allocation field; and determining, based on the part of the PUSCH frequency resource allocation field, the target early configuration of the at least one early configuration.

[0212] In some example embodiments, determining, based on the indication, the target early configuration of the at least one early configuration comprises: determining, based on the one or more repurposed bits in the RAR, the target early configuration of the at least one early configuration.

[0213] In some example embodiments, the method 800 further comprises: transmitting, to the network apparatus and before completion of a RACH procedure, capability information associated with the at least one early configuration.

[0214] In some example embodiments, the RAR message further comprises a request for the capability information.

[0215] In some example embodiments, transmitting to the network apparatus the capabilityinformation comprises: transmitting, in a message 3 of the RACH procedure, the capability information indicating a CSI report to be provided to the network apparatus.

[0216] In some example embodiments, the method 800 further comprises: receiving, from the network apparatus, downlink control information (DCI) indicating a PUCCH resource or a PUSCH resource for carrying the CSI report, the DCI scheduling a physical downlink shared channel (PDSCH) for a message 4 of the RACH procedure.

[0217] In some example embodiments, the method 800 further comprises: transmitting, to the network apparatus, the CSI report in acknowledgement of the message 4.

[0218] In some example embodiments, the method 800 further comprises: performing a CSI-RS measurement based on the CSI-RS configuration prior to starting the RACH procedure, performing a CSI-RS measurement based on the CSI-RS configuration prior to receiving the RAR message in the RACH procedure, or performing a CSI-RS measurement based on the CSI-RS configuration after determining that the CSI-RS configuration is the target early configuration based on the indication in the RAR message.

[0219] In some example embodiments, the method 800 further comprises: determining the CSI report based on the stored information associated with the at least one early configuration.

[0220] In some example embodiments, transmitting to the network apparatus the capability information comprises: transmitting, in a message 3 of the RACH procedure, the capability information indicating an early SRS transmission.

[0221] In some example embodiments, the method 800 further comprises: transmitting, in the message 3 of the RACH procedure, at least one of a candidate SRS configuration or a resource needed for the early SRS transmission.

[0222] In some example embodiments, the method 800 further comprises: receiving, from the network apparatus, downlink control information (DCI) indicating a trigger of transmitting an SRS, the DCI scheduling a PDSCH for a message 4 of the RACH procedure.

[0223] In some example embodiments, the method 800 further comprises: determining, from the at least one early configuration, an SRS configuration as the target early configuration based on the indication in the RAR message; and transmitting the SRS based on the SRS configuration to the network apparatus.

[0224] In some example embodiments, the method 800 further comprises: transmitting an SRS based on the SRS configuration to the network apparatus prior to starting the RACH procedure.

[0225] In some example embodiments, the method 800 further comprises: performing at least one of a CSI measurement or CSI calculation based on the at least one of the CSI-RS configuration or the CSI report configuration prior to starting the RACH procedure or prior to receiving the RAR message in the RACH procedure.

[0226] In some example embodiments, the method 800 further comprises: determining, from the at least one of the CSI measurement or the CSI calculation, a CSI report based on the indication in the RAR message; and transmitting, in a message 3 of the RACH procedure, the CSI report.

[0227] In some example embodiments, a terminal apparatus capable of performing any of the method 800 (for example, the terminal apparatus 110 in FIG. 1) may comprise means for performing the respective operations of the method 800. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module. The terminal apparatus may be implemented as or included in the terminal apparatus 110 in FIG. 1 .

[0228] In some example embodiments, the terminal apparatus comprises means for receiving, from a network apparatus, an early configuration message prior to starting a random access channel (RACH) procedure or transitioning to a radio resource control (RRC) idle or inactive state, the early configuration message indicating at least one early configuration comprising a previous configuration used by the terminal apparatus in a previous RRC connected state or a reference configuration indicating the previous configuration; means for storing information associated with the previous configuration in the RRC idle or inactive state; means for receiving, from the network apparatus, a random access response (RAR) message comprising an indication associated with the at least one early configuration; and means for determining, based on at least the indication, a target early configuration of the at least one early configuration.

[0229] In some example embodiments, the early configuration message comprises at least one of: a system information block (SIB) message, a RRC release message, or a RRC suspend message.

[0230] In some example embodiments, the target early configuration comprises at least one of: a sounding reference signal (SRS) configuration, a channel state information (CSI) reference signal (RS) configuration, or a CSI report configuration.

[0231] In some example embodiments, the terminal apparatus further comprises: means for reusing the information associated with the previous configuration prior to starting the RACH procedure, after transitioning to a RRC connected state, or after determining based on the indication that the previous configuration is at least a portion of the target early configuration.

[0232] In some example embodiments, the means for reusing the information associated with theprevious configuration prior to starting the RACH procedure or after transitioning to the RRC connected state comprises: means for in response to receiving the early configuration message, determining whether the information associated with the previous configuration is stored in the terminal apparatus; and means for in accordance with a determination that the information associated with the previous configuration is stored in the terminal apparatus, determining to perform an operation based on the previous configuration by reusing the information associated with the previous configuration.

[0233] In some example embodiments, the information associated with the previous configuration comprises at least one of: previous parametrization of the previous configuration, a CSI measurement, a reference signal configuration used for a CSI measurement, a CSI report quantity, or CSI calculation information.

[0234] In some example embodiments, the terminal apparatus further comprises: means for receiving, from the network apparatus, at least a portion of the information associated with the previous configuration in the previous RRC connected state.

[0235] In some example embodiments, the means for storing the information associated with the previous configuration in the RRC idle or inactive state comprises: means for in response to receiving a RRC release message or a RRC suspend message in the previous RRC connected state, determining to store the information associated with the previous configuration in the RRC idle or inactive state.

[0236] In some example embodiments, the indication associated with the at least one early configuration is indicated by one or more bits in the RAR message and the one or more bits comprise at least one of: a CSI request bit, a bit in a physical uplink shared channel (PUSCH) frequency resource allocation field, or one or more repurposed bits in the RAR message.

[0237] In some example embodiments, the means for determining, based on the indication, the target early configuration of the at least one early configuration comprises: means for determining, based on the CSI request bit, a part of the PUSCH frequency resource allocation field; and means for determining, based on the part of the PUSCH frequency resource allocation field, the target early configuration of the at least one early configuration.

[0238] In some example embodiments, the means for determining, based on the indication, the target early configuration of the at least one early configuration comprises: means for determining, based on the one or more repurposed bits in the RAR, the target early configuration of the at least one early configuration.

[0239] In some example embodiments, the terminal apparatus further comprises: means for transmitting, to the network apparatus and before completion of a RACH procedure, capability information associated with the at least one early configuration. In some example embodiments, the RAR message further comprises a request for the capability information.

[0240] In some example embodiments, the means for transmitting to the network apparatus the capability information comprises: means for transmitting, in a message 3 of the RACH procedure, the capability information indicating a CSI report to be provided to the network apparatus.

[0241] In some example embodiments, the terminal apparatus further comprises: means for receiving, from the network apparatus, downlink control information (DCI) indicating a PUCCH resource or a PUSCH resource for carrying the CSI report, the DCI scheduling a physical downlink shared channel (PDSCH) for a message 4 of the RACH procedure.

[0242] In some example embodiments, the terminal apparatus further comprises: means for transmitting, to the network apparatus, the CSI report in acknowledgement of the message 4.

[0243] In some example embodiments, the terminal apparatus further comprises: means for performing a CSI-RS measurement based on the CSI-RS configuration prior to starting the RACH procedure, means for performing a CSI-RS measurement based on the CSI-RS configuration prior to receiving the RAR message in the RACH procedure, or means for performing a CSI-RS measurement based on the CSI-RS configuration after determining that the CSI-RS configuration is the target early configuration based on the indication in the RAR message.

[0244] In some example embodiments, the terminal apparatus further comprises: means for determining the CSI report based on the stored information associated with the at least one early configuration.

[0245] In some example embodiments, the means for transmitting to the network apparatus the capability information comprises: means for transmitting, in a message 3 of the RACH procedure, the capability information indicating an early SRS transmission.

[0246] In some example embodiments, the terminal apparatus further comprises: means for transmitting, in the message 3 of the RACH procedure, at least one of a candidate SRS configuration or a resource needed for the early SRS transmission.

[0247] In some example embodiments, the terminal apparatus further comprises: means for receiving, from the network apparatus, downlink control information (DCI) indicating a trigger of transmitting an SRS, the DCI scheduling a PDSCH for a message 4 of the RACH procedure.

[0248] In some example embodiments, the terminal apparatus further comprises: means for determining, from the at least one early configuration, an SRS configuration as the target early configuration based on the indication in the RAR message; and means for transmitting the SRS based on the SRS configuration to the network apparatus.

[0249] In some example embodiments, the terminal apparatus further comprises: means for transmitting an SRS based on the SRS configuration to the network apparatus prior to starting the RACH procedure.

[0250] In some example embodiments, the terminal apparatus further comprises: means for performing at least one of a CSI measurement or CSI calculation based on the at least one of the CSI- RS configuration or the CSI report configuration prior to starting the RACH procedure or prior to receiving the RAR message in the RACH procedure.

[0251] In some example embodiments, the terminal apparatus further comprises: means for determining, from the at least one of the CSI measurement or the CSI calculation, a CSI report based on the indication in the RAR message; and means for transmitting, in a message 3 of the RACH procedure, the CSI report.

[0252] FIG. 9 is a simplified block diagram of a device 900 that is suitable for implementing example embodiments of the present disclosure. The device 900 may be provided to implement a communication device, for example, the terminal apparatus 110 or the network apparatus 120 as shown in FIG. 1. As shown, the device 900 includes one or more processors 910, one or more memories 920 coupled to the processor 910, and one or more communication modules 940 coupled to the processor 910.

[0253] The communication module 940 is for bidirectional communications. The communication module 940 has one or more communication interfaces to facilitate communication with one or more other modules or devices. The communication interfaces may represent any interface that is necessary for communication with other network elements. In some example embodiments, the communication module 940 may include at least one antenna.

[0254] The processor 910 may be of any type suitable to the local technical network and may include one or more of the following: general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on multicore processor architecture, as non-limiting examples. The device 900 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock which synchronizes the main processor.

[0255] The memory 920 may include one or more non-volatile memories and one or more volatile memories. Examples of the non-volatile memories include, but are not limited to, a Read Only Memory (ROM) 924, an electrically programmable read only memory (EPROM), a flash memory, a hard disk, a compact disc (CD), a digital video disk (DVD), an optical disk, a laser disk, and other magnetic storage and / or optical storage. Examples of the volatile memories include, but are not limited to, a random-access memory (RAM) 922 and other volatile memories that will not last in the power-down duration.

[0256] A computer program 930 includes computer executable instructions that are executed by the associated processor 910. The instructions of the program 930 may include instructions for performing operations / acts of some example embodiments of the present disclosure. The program 930 may be stored in the memory, e.g., the ROM 924. The processor 910 may perform any suitable actions and processing by loading the program 930 into the RAM 922.

[0257] The example embodiments of the present disclosure may be implemented by means of the program 930 so that the device 900 may perform any process of the disclosure as discussed with reference to FIG. 2 to FIG. 8. The example embodiments of the present disclosure may also be implemented by hardware or by a combination of software and hardware.

[0258] In some example embodiments, the program 930 may be tangibly contained in a computer readable medium which may be included in the device 900 (such as in the memory 920) or other storage devices that are accessible by the device 900. The device 900 may load the program 930 from the computer readable medium to the RAM 922 for execution. In some example embodiments, the computer readable medium may include any types of non-transitory storage medium, such as ROM, EPROM, a flash memory, a hard disk, CD, DVD, and the like. 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).

[0259] FIG. 10 shows an example of the computer readable medium 1000 which may be in form of CD, DVD or other optical storage disk. The computer readable medium 1000 has the program 930 stored thereon.

[0260] Generally, various embodiments of the present disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects may be implemented in hardware, and other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. Although various aspects of embodiments of the present disclosure are illustrated and described as block diagrams, flowcharts, orusing some other pictorial representations, it is to be understood that the block, apparatus, system, technique or method described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

[0261] Some example embodiments of the present disclosure also provide at least one computer program product tangibly stored on a computer readable medium, such as a non-transitory computer readable medium. The computer program product includes computer-executable instructions, such as those included in program modules, being executed in a device on a target physical or virtual processor, to carry out any of the methods as described above. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, or the like that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or split between program modules as desired in various embodiments. Machineexecutable instructions for program modules may be executed within a local or distributed device. In a distributed device, program modules may be located in both local and remote storage media.

[0262] Program code for carrying out methods of the present disclosure may be written in any combination of one or more programming languages. The program code may be provided to a processor or controller of a general-purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program code, when executed by the processor or controller, cause the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The program code may execute entirely on a machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

[0263] In the context of the present disclosure, the computer program code or related data may be carried by any suitable carrier to enable the device, apparatus or processor to perform various processes and operations as described above. Examples of the carrier include a signal, computer readable medium, and the like.

[0264] The computer readable medium may be a computer readable signal medium or a computer readable storage medium. A computer readable medium may include but not limited to an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the computer readable storage medium would include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random-access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-onlymemory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0265] Further, although operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Likewise, although several specific implementation details are contained in the above discussions, these should not be construed as limitations on the scope of the present disclosure, but rather as descriptions of features that may be specific to particular embodiments. Unless explicitly stated, certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, unless explicitly stated, various features that are described in the context of a single embodiment may also be implemented in a plurality of embodiments separately or in any suitable subcombination.

[0266] Although the present disclosure has been described in languages specific to structural features and / or methodological acts, it is to be understood that the present disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

WHAT IS CLAIMED IS:1 . A terminal apparatus comprising: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the terminal apparatus to: receive, from a network apparatus, an early configuration message prior to starting a random access channel (RACH) procedure or transitioning to a radio resource control (RRC) idle or inactive state, the early configuration message indicating at least one early configuration comprising a previous configuration used by the terminal apparatus in a previous RRC connected state or a reference configuration indicating the previous configuration; store information associated with the previous configuration in the RRC idle or inactive state; receive, from the network apparatus, a random access response (RAR) message comprising an indication associated with the at least one early configuration; and determine, based on at least the indication, a target early configuration of the at least one early configuration.

2. The terminal apparatus of claim 1 , wherein the early configuration message comprises at least one of: a system information block (SIB) message, a RRC release message, or a RRC suspend message.

3. The terminal apparatus of claim 1 or 2, wherein the target early configuration comprises at least one of: a sounding reference signal (SRS) configuration, a channel state information (CSI) reference signal (RS) configuration, or a CSI report configuration.

4. The terminal apparatus of any of claims 1 to 3, wherein the terminal apparatus is further caused to: reuse the information associated with the previous configuration prior to starting the RACH44 procedure, after transitioning to a RRC connected state, or after determining based on the indication that the previous configuration is at least a portion of the target early configuration.

5. The terminal apparatus of claim 4, wherein reusing the information associated with the previous configuration prior to starting the RACH procedure or after transitioning to the RRC connected state comprises: in response to receiving the early configuration message, determining whether the information associated with the previous configuration is stored in the terminal apparatus; and in accordance with a determination that the information associated with the previous configuration is stored in the terminal apparatus, determining to perform an operation based on the previous configuration by reusing the information associated with the previous configuration.

6. The terminal apparatus of any of claims 1 to 5, wherein the information associated with the previous configuration comprises at least one of: previous parametrization of the previous configuration, a CSI measurement, a reference signal configuration used for a CSI measurement, a CSI report quantity, orCSI calculation information.

7. The terminal apparatus of any of claims 1 to 6, wherein the terminal apparatus is further caused to: receive, from the network apparatus, at least a portion of the information associated with the previous configuration in the previous RRC connected state.

8. The terminal apparatus of any of claims 1 to 7, wherein storing the information associated with the previous configuration in the RRC idle or inactive state comprises: in response to receiving a RRC release message or a RRC suspend message in the previous RRC connected state, determining to store the information associated with the previous configuration in the RRC idle or inactive state.

9. The terminal apparatus of any of claims 1 to 8, wherein the indication associated with the at least one early configuration is indicated by one or more bits in the RAR message and the one or more bits comprise at least one of:a CSI request bit, a bit in a physical uplink shared channel (PUSCH) frequency resource allocation field, or one or more repurposed bits in the RAR message.

10. The terminal apparatus of claim 9, wherein determining, based on the indication, the target early configuration of the at least one early configuration comprises: determining, based on the CSI request bit, a part of the PUSCH frequency resource allocation field; and determining, based on the part of the PUSCH frequency resource allocation field, the target early configuration of the at least one early configuration.11 . The terminal apparatus of claim 9, wherein determining, based on the indication, the target early configuration of the at least one early configuration comprises: determining, based on the one or more repurposed bits in the RAR, the target early configuration of the at least one early configuration.

12. The terminal apparatus of any of claims 1 to 11 , wherein the terminal apparatus is further caused to: transmit, to the network apparatus and before completion of a RACH procedure, capability information associated with the at least one early configuration.

13. The terminal apparatus of claim 12, wherein the RAR message further comprises a request for the capability information.

14. The terminal apparatus of claim 12 or 13, wherein transmitting to the network apparatus the capability information comprises: transmitting, in a message 3 of the RACH procedure, the capability information indicating a CSI report to be provided to the network apparatus.

15. The terminal apparatus of claim 14, wherein the terminal apparatus is further caused to: receive, from the network apparatus, downlink control information (DCI) indicating a PUCCH resource or a PUSCH resource for carrying the CSI report, the DCI scheduling a physical downlink shared channel (PDSCH) for a message 4 of the RACH procedure.

16. The terminal apparatus of claim 15, wherein the terminal apparatus is further caused to: transmit, to the network apparatus, the CSI report in acknowledgement of the message 4.

17. The terminal apparatus of any of claims 14 to 16, wherein the early configuration message comprises a system information block (SIB) message indicating a CSI-RS configuration, and the terminal apparatus is further caused to: perform a CSI-RS measurement based on the CSI-RS configuration prior to starting the RACH procedure, perform a CSI-RS measurement based on the CSI-RS configuration prior to receiving the RAR message in the RACH procedure, or perform a CSI-RS measurement based on the CSI-RS configuration after determining that the CSI-RS configuration is the target early configuration based on the indication in the RAR message.

18. The terminal apparatus of any of claims 14 to 17, wherein the terminal apparatus is further caused to: determine the CSI report based on the stored information associated with the at least one early configuration.

19. The terminal apparatus of claim 12 or 13, wherein transmitting to the network apparatus the capability information comprises: transmitting, in a message 3 of the RACH procedure, the capability information indicating an early SRS transmission.

20. The terminal apparatus of claim 19, wherein the terminal apparatus is further caused to: transmitting, in the message 3 of the RACH procedure, at least one of a candidate SRS configuration or a resource needed for the early SRS transmission.21 . The terminal apparatus of claim 19 or 20, wherein the terminal apparatus is further caused to: receive, from the network apparatus, downlink control information (DCI) indicating a trigger of transmitting an SRS, the DCI scheduling a PDSCH for a message 4 of the RACH procedure.

22. The terminal apparatus of claim 21 , wherein the terminal apparatus is further caused to: determine, from the at least one early configuration, an SRS configuration as the target earlyconfiguration based on the indication in the RAR message; and transmit the SRS based on the SRS configuration to the network apparatus.

23. The terminal apparatus of any of claims 1 to 13, wherein the early configuration message comprises a system information block (SIB) message indicating an SRS configuration, and the terminal apparatus is further caused to: transmit an SRS based on the SRS configuration to the network apparatus prior to starting the RACH procedure.

24. The terminal apparatus of any of claims 1 to 13, wherein the early configuration message comprises a system information block (SIB) message indicating at least one of a CSI-RS configuration or a CSI report configuration, and the terminal apparatus is further caused to: perform at least one of a CSI measurement or CSI calculation based on the at least one of the CSI-RS configuration or the CSI report configuration prior to starting the RACH procedure or prior to receiving the RAR message in the RACH procedure.

25. The terminal apparatus of claim 24, the terminal apparatus is further caused to: determine, from the at least one of the CSI measurement or the CSI calculation, a CSI report based on the indication in the RAR message; and transmit, in a message 3 of the RACH procedure, the CSI report.

26. A method comprising: receiving, at a terminal apparatus and from a network apparatus, an early configuration message prior to starting a random access channel (RACH) procedure or transitioning to a radio resource control (RRC) idle or inactive state, the early configuration message indicating at least one early configuration comprising a previous configuration used by the terminal apparatus in a previous RRC connected state or a reference configuration indicating the previous configuration; storing information associated with the previous configuration in the RRC idle or inactive state; receiving, from the network apparatus, a random access response (RAR) message comprising an indication associated with the at least one early configuration; and determining, based on at least the indication, a target early configuration of the at least one early configuration.

27. A terminal apparatus comprising:48 means for receiving, from a network apparatus, an early configuration message prior to starting a random access channel (RACH) procedure or transitioning to a radio resource control (RRC) idle or inactive state, the early configuration message indicating at least one early configuration comprising a previous configuration used by the terminal apparatus in a previous RRC connected state or a reference configuration indicating the previous configuration; means for storing information associated with the previous configuration in the RRC idle or inactive state; means for receiving, from the network apparatus, a random access response (RAR) message comprising an indication associated with the at least one early configuration; and means for determining, based on at least the indication, a target early configuration of the at least one early configuration.

28. A non-transitory computer readable medium comprising instructions stored thereon for causing an apparatus at least to perform the method of claim 26.

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