OA20545A - Handling of inactive/idle measurement configurations and inactive/idle measurements upon inter-RAT cell reselection. - Google Patents

Abstract

Systems and methods are disclosed herein that relate to handling of dormant state measurement configurations and associated measurements upon inter-Radio Access Technology (RAT) cell reselection. In some embodiments, a method performed by a wireless device comprises receiving one or more dormant state measurement configurations from a network node of a source RAT, performing measurements while in a dormant state in accordance with at least one of the one or more dormant state measurement configurations, and performing an inter-RAT cell reselection from the source RAT to a target RAT while in the dormant state. The method further comprises, upon performing the inter-RAT cell reselection, performing one or more actions to handle dormant state measurement configurations and/or measurements performed in accordance with dormant state measurement configurations. Corresponding embodiments of a wireless device are also disclosed.

Description

HANDLING OF 1NACT1VE/1DLE MEASUREMENT CONFIGURATIONS AND INACTIVE/IDLE MEASUREMENTS UPON INTER-RAT CELL RESELECTION

Related Applications

This application daims the benefit of provisional patent application serial number 62/825,430, filed March 28, 2019, the disclosure of which is hereby incorporated herein by reference in its entirety.

Technicai Field

The present disdosure relates to inactive/ide measurements performed by a wireless device and, in particuiar, io handïing of înad^ve/idle measurements upon interRadio Access Technology (RAT) cell reselection.

Backqround

1.1 Carrier Aggregation (CA) and Dual Connectivity (DC) in Long Term Evolution (LTE)

In Release 10, CA was introduced in LTE to enabie the User Equipment (UE) to transmit and/or receive information via mdtipte cells (so called Secondary Cells = SCe!l(s)) from multiple carrier fréquences such that the UE can benefît from the exîsting non-contiguous and contiguous carriers. In CA tenminology, the Primary Cell (PCelt) is the cell towards which the UE establishes the Radio Resource Control (RRC) connection or performs handover. In CA, cells are aggregated on the Medium Access Control (MAC) level. The MAC layer gets grants for a certain cell and multiplexes data from different bearers to one transport biock being sent on that cell. Also, the MAC layer Controls how that process is dune. This is iliustratêd în Figure 1.

SCells can be added (i.e., configured) for the UE using RRC signaling (e.g., RRCConnectionReconfiguration), which takes on the order of hundreds of milliseconde. A cell which is configured for the UE becomes a “serving cell for this UE. An SCell may also be associated with an SCell state. When configured/added via RRC, an SCell starts in deactivated State, in LTE Release 15, frie enhanced or evolved Node B (eNB) can indicate to activate-upon-configuration, or change the State, at least in RRCReconfiguration, as shown below (from Third Génération Partnership Project (3GPP) Technicai Spécification (TS) 36.331 V15.3.0):

1> for each SCeiî configured for the UE other than the PSCeik

2> if the received RRCConnectionReconfiguration message includes sCellState for the SCell and indicates activated:

3> configure loweriayersto considerthe SCell to be in activated State;

2>else if the received RRCConnectionReconfiguration message includes sCellState for the SCeli and indicates dormant

3> configure lower layers to consider the SCell to be in dormant State;

2>else:

> configure Icwer layers to consider the SCel! to be in deactivated State,

In LTE Release 15, a new intermediate state between the deactivated and active State has been introduced for enhanced upünk operation. This new intermediate state is referred to as the “dormant” state. A MAC Control Elément (CE) can be used to change the SCell state between the three States as shown in Figure 2. There are also timers in the MAC layer to move a cell between deactivated/activated/dormant. These timers are:

- sCeliHibernationTimer, which moves the SCell from activated state to dormant state,

- sCeNDeactivationTimer, which moves the SCell from activated state to deactivated state, dormantSCellDeactivationTimer, which moves the SCell from donnant State to deactivated state.

The MAC leve! SCell activation takes on the order of 20-30 milliseconds (ms).

Once the network understands the need to configure and/or activate CA. the question is which cells to initially configure and/or activate, if they are configured, and/or whether a cell/carrier is good enough in terms of radio quality/coverage (e.g., Reference Signal Received Power (RSRP) and Reference Signal Received Quality (RSRQ)). To understand the conditions on SCeli(s) or potential SCell(s) on a given available carrier, the network may configure the UE to perforrn Radio Rësourcë Management (RRM) measurements.

Typically, the network may be assisted by RRM measurements to be reported by a UE. The network may configure the UE with measurement Identities (IDs) associated to reportConfig with event A1 (serving cell becomes better than threshold) in case this is a configured SCell, or A4 (neighbor cell becomes better than threshold) for carriers without a configured SCell. The measurement objects are associated to the carrier the network wants reports on. If the network is aware of the exact cells it wants the UE to measure, a so-called white cell list can be configured in the measurement object so that the UE is only required to measure these ceiis in that carrier.

F igure 3 illustrâtes a process in which the network décidés to setup CA or DC for a UE. The network then configures the UE to perforrn measurements, and the UE sends the appropriate measurement reports to the network. Based on the received measurement reports, the network makes a decision on SCell addition or SCell activation and then configures the UE to add the selected SCell(s).

With the introduction of DC in Release 12, it was possible to add what is called 5 Secondary Cell Group (SCG) configuration fo the UE. The main benefit would be that the UE could in principle add a cell from another eNB. Protocol-wise, that would require different MAC entities, one for each cell group. The UE wilt hâve two cell groups, one associated to the PCell (master node) and another associated to a Pnmary Secondary Cell (PSCell) (of the secondary eNB), where each group may possibly hâve their own 10 associated SCells.

When it cornes to adding SCeîis, when the UE is in single connectivity, the RRCConnection Reconfiguration message may carry a cell index (so MAC identifiers are optimized, Le., shorter), cell identifier and carrier frequency, common parameters, and state information, intrcduced in Release 15 (activated or dormant).

Below the SCellToAddModList included in the RRCConnectionReconfiguration is iilustrated and described.

SCelIToAddModList-rlO :i= SCellToAddMod-r10	SEQUENCE (SIZE	(1..maxSCe!l-r10))	OF
SCellToAddMod-r10 :: = sCelllndex-r10 cellldentification-r10 physCellîd-r10 dl-CarrierFreq-r10 }	SEQUENCE{ SCe!llndex-r10, SEQUENCE{ PhysCellîd, ARFCN-ValueEUTRA OPTIONAL,-	Cond

SCell Add radioResourceConfigCommonSCell-rlO RadioResourceConfigCommonSCell· r10 OPTiONAL, — Cond SCëiiAdd radioResourceConfigDedicatedSCell-r10 RadioResourceConfigDedicatedSCell-r10

[[ dl-CarnerFreq-v1090 ARFCN-ValueEUTRA-v9eO OPTIONAL Cond EARFCN-max

H.

[[ antennalnfoDedicatedSCell-v10i0 AntennalnfoDedicated-v10i0

OPTIONAL- Need ON h,

[[ srs-SwitchFromServCelllndex-r14 INTEGER (0.. 31) OPTIONAL - Need ON

]].

[[ sCeilState-r15 ENUmERATED {activated, dormant}

OPTiONAL -- Need ON

Ώ

I RRCConnectionReconfiguration field descriptions j sCeilConfigCommon i Indicates the common configuration forthe SCell group.

sCelIGroupIndex

Indicates the idenfity of SCell groups forwhich a common configuration is provided.

i sCeH/ndex ! In case of DC, the SCellIndex is unique within the scope of the UE i.e. an SCG cell cas I not use the same value as used for an MCG cell. For pSCellToAddMod, if sCellindex-r!

is présent the UE shall ignore sCelllndex-r12. sCei!lndex-r13 in sCelIToAddModLîstExi r13 shall not hâve same values as sCeilindex-r10 in sCeîlToAddModList-r10.

sCcllGroupToAddModList, sCellGroupToAddModListSCG

I ί Indicates the SCell group to be added or modified. E-UTRAN only configures at most <

! SCell groups per UE over aii ceil groups.

sCellGroupfoReieaseList

I Indicates the SCell group to be released.

[ s Ce!!State ; δ fjeîd that indicates whether the SCell shall be considered to be in activated o r

i dormant State upon SCell configuration.

! sCeilToAddModList sCeHToAddModListExt !

i indicates the SCell to be added or modified. Field sCeüToAddModüst is used to add the ; î first 4 SCells for a UE with sCellindex-rlO while sCellToAddModListExtis used to add this i : rest. If E-UTRAN includes sCei!ToAddModListExt-v1430 it includes the same number cf | entries, and Iisted in the same order, as in sCeliToAddrâodUstExt-r13. If E-UTRAN i includes sCel!ToAddModList-v10IO it includes the same number of entries, and iisted in j i the same order, as in sCellToAddModUst-rlO. If E-UTRAN include / ' sCelIToAddModListExt-vl 370 it includes the same number of entries, and iisted in the i j same order, as in sCellToAddModUstExt-rlO. If E-UTRAN include >i | sCellToAddModListExt-v13cO it includes the same number of entries, and Iisted in the | ; same order, as in sCellToAddMQdüstExt-r13. J sCellToAddModListSCG, sCeilToAddModUstSCG-Ext 5 j Indicates the SCG cell to be added or modified. The field is used for SCG cells otherthan j ; the PSCel! (which is added/ modified by field pSCellToAddMod). Field ;

sCellToAddModListSCG is used to add the first 4 SCells for a UE with sCeliindex-rî ) ; while sCe!IToAddModListSCG-Ext is used to add the rest. If E-UTRAN include ï î ; sCelIToAddModüstSCG-vlOlO it includes the same number of entries, and Iisted in the i | same order, as in sCe!IToAddModUstSCG-r12. If E-UTRAN includes j î sCellToAddModListSCG-Ext-vl 370 it includes the same number of entries, and Iisted in j î the same order, as in sCellToAddModListSCG-Ext-r13. !f E-UTRAN include 5 l sCellToAddModListSCG-Ext-vl3c0 it includes the same number of entries, and Iisted in î the same order, as in sCeÎîToAddModListSCG-Exî-rl3. j sCe/ZToRc/easeListSCG, sCeHToReleaseListSCG-Ext । Indicates the SCG cell to be released. The field is also used to release the PSCell e.g. i | upon change of PSCell, upon System information change for the PSCell,

The procedure to add SCells to the Master Ce!! Group (MCG) in LTE (or to modify) is described as follows (as in 3GPP TS 36.331 V15.3.0):

5.3.5.3 Réception of an RRCConnectionReconfiguration not including the mobifityControIlnfo by the UE

If the RRCConnectionReconfiguration message does not include the mobilityControIlnfo and the UE is able to comply with the configuration included in this message, the UE shall:

1>if the received RRCConnectionReconfiguration includes the sCelIToAddModList: 2> perform SCell addition or modification as specified in 5.3.10.3b;

5.3.10.3b SCell addition/ modification

The UE shall:

1>for each sCellIndex value included either in the sCelIToAddModList or in the sCellToAddModListSCG that is not part of the current UE configuration (SCell addition):

2>add the SCell, corresponding to the cellIdentification, in accordance with the radioResourceConfigCommonSCeli and radioResourceConfigDedicatedSCeli, both included either in the sCelIToAddModList or in the sCellToAddModListSCG·,

2> if sCellState is configured for the SCell and indicates activated:

3> configure lower layers to consider the SCell to be in activated state;

2> else if sCeiiState is configured for the SCell and indicates dormant:

3> configure lower layers to consider the SCell to be in dormant state;

2> e!se:

3> configure lower layers to consider the SCell to be in deactivated state;

2> for each measld included in the measIdList within VarMea-sConfig:

3>if SCells are not applicable for the associated measurement; and

3> if the concerned SCell is included in cellsTriggeredList defîned within the

VarMeasReportList for this measld:

4>remove the concerned SCell from cellsTriggeredList defîned within the VarMeasReportList for this measld;

1>for each sCellIndex value included either in the sCelIToAddModList or in the sCellToAddModListSCG that is part of the current UE configuration (SCell modification);

2>modify the SCell configuration in accordance with the radioResourceConfigDedicatedSCeil, included either in the sCelIToAddModList or in the sCellToAddModListSCG',

1.2 inter- Radio Access Technology (RAT) and Inter Fifth Génération Core (5GC) interworking in LTE and New Radio (NR)

Fifth Génération (5G) in 3GPP introduces both a new core network, which is referred to as the 5GC, and a new Radio Access Network (RAN), which is referred to as NR. The 5GC will, however, also support RATs other than NR. It has been agreed that LTE (i.e., Evolved Universal Terrestnal Radio Access (E-UTRA)) should also be connected to 5GC. LTE base stations (eNBs) that are connected to 5GC are called ngeNBs and are part of Next Génération RAN (NG-RAN), which also includes NR base stations called gNBs. Figure 4 shows howthe base stations are connected îo each other and the nodes in 5GC. In particular, Figure 4 is the 5G System (5GS) architecture containing 5GC and NG-RAN.

There are dînèrent ways to depioy a 5G network with or without interworking with LTE and Evolved Racket Core (EPC), as depicted in Figure 5. In principle, NR and LTE can be deployed without any interworking, denoted by NR Stand-Alone (SA) operation, that is the gNB in N R can be connected to 5GC and the eNB can be connected to EPC with no interconnection between the two (Option 1 and Option 2 in Figure 5). On the other hand, the first supported version of NR is the so-called Evolved Universal Terrestnal Radio Access Network (E-UTRAN) NR DC (EN-DC), illustrated by Option 3 in Figure 5. In such a déployaient, DC between NR and LTE is appiied with LTE as the master and NR as the secondary node. The RAN node (gNB) supporting NR may not hâve a control plane connection to the core network (EPC); instead, the gNB relies on the LTE as master node (Master eNB (MeNB)). This is also called “Non-standalone NR. Notice that in this case the functiûnahty of an N R ce il is lirniied and would be used for connected mode UEs as a booster and/or diversity leg, but an RRC_IDLE UE cannot camp on these N R cell s.

With introduction of 5GC, other options may be also valid. As mentioned above, Option 2 in Figure 5 supports SA NR depioyment where the gNB is connected to 5GC. Simslarly, LTE can also be connected to 5GC using Option 5 (also known as enhanced LTE (eLTE), E-UTRA/5GC, or LTE/5GC and the node can be referred to as an ng-eNB). In these cases, both NR and LTE are seen as part of the NG-RAN (and both the ng-eNB and the gNB can be referred to as NG-RAN nodes). It is worth noting that Option 4 and Option 7 are other variants of DC between LTE and NR which wiii be standardized as part of NG-RAN connected to 5GC, denoted by Multi-Radio DC (MR-DC). Under the MRDC umbrella, we hâve:

• EN-DC (Option 3): LTE is the master node and NR is the secondary node (EPC Core Network (CN) employed) • NR E-UTRA (NE) - DC (Option 4): NR is the master node and LTE is the secondary node (5GC employed) • Next Génération (NGEN) DC (Option 7): LTE is the master node and NR is the secondary node (5GC employed) « NR-DC (variant of Option 2): DC where both the master and secondary nodes are NR (5GC employed).

As migration for these options may differ from different operators, it is possible to hâve deployments with multiple options in parallel in the same network, e.g. there could be an eNB base station supporting options 3, 5, and 7 in the same network as an NR base station supporting options 2 and 4. In combination with DC solutions between LTE and NR, it is also possible to support CA in each cell group (i.e,, MCG and SCG) and DC between nodes on the same RAT (e.g., NR-NR DC). For the LTE cells, a conséquence of these different deployments is the co-existence of LTE cells associated to eNBs connected to EPC, 5GC, or both EPC/5GC.

1.3 Suspend/Resume in LTE and Relation to CA/SCel! and SCG Additions

A very typical scénario or use case is a UE with some burst traffic that cornes and goes, e.g. some video packets and idle période of transmission/reception, then cornes live again. To save UE power, the network transitions the UE from connected to idle during these periods. Then, the UE cornes back again, either via paging or UE request to get connected, and accesses the network.

In LTE Release 13, a mechanism was introduced for the UE to be suspended by the network in a suspended State similar to RRC_ïDLE but with the différence that the UE stores the Access Stratum (AS) context or RRC context. This makes it possible to reduce the signaling when the UE is becoming active again by resuming the RRC connection, instead of as prior to establish the RRC connection from scratch. Reducing the signaling could hâve several benefits:

reduced latency, e.g., for smart phones accessing the Internet, and reduced signaling, which leads to reduced battery consumption for machine type devices sendîng very little data.

The Release 13 solution is based on the UE sending an RRCConnectionResumeRequest message to the network and, in response, the UE may receive an RRCConnectionResume from frie network. The RRCConnectionResume is not encrypted but integrity protected.

The résumé procedure in LTE can be found in the RRC spécifications (3GPP TS 36.331). As the UE performing résumé is in RRG_!DLE with suspended AS context, a transition from RRCJDLE to RRC_CONNECTED is triggered. Hence, this is modelled in the spécifications in the same subclause that captures the RRC connection establishment (i.e., subclause 5.3.3 RRC connection establishment).

There are few things relevant to highüght in the SCG configurations and SCel!

configurations for MCGs in relation to suspend/resume procedures. Upon suspension, it is defined that the UE stores its used RRC configuration. In other words, if the UE is operating in any DC mode and has an SCG configuration or just has configured SCeils in the MCG, the UE stores ail these configurations. However, upon résumé, at least until Release 15, it is defined that the UE reieases the SCG configurations and SCell configurations, as shown below:

5.3.3.2 Initiation

The UE initiâtes the procedure when upper layers request establishment or résumé of an RRC connection while the UE is in RRCJDLE or when upper layers request résumé of an RRC connection or RRC layer requests résumé of an RRC connection for, e.g. RNAU or réception of RAN paging while the UE is in RRCJNACTIVE.

Except for NB-loT, upon initiating the procedure, if connected to EPC or 5GC, the UE shall:

1> if the UE is resuming an RRC connection from a suspended RRC connection or from RRCJNACTIVE:

2> if the UE is resuming an RRC connection from a suspended RRC connection:

3> if the UE was configured with EN-DC:

4>perform EN-DC release, as specified in TS 38.331 [82], clause 5.3.5.10;

2> release the MCG SCelf(s), if configured, in accordance with 5.3.10.3a;

2> release the entire SCG configuration, if configured, except for the DRB configuration (as configured by drb-ToAddModLîstSCG);

Hence, when the UE comes from RRCJDLE with the context, if the network wants to add SCeil(s) to the MCG or add an SCG, the network needs to do that from scratch, even if the UE is suspending and resuming in the same cell/area where ail the previous PCell and SCell configurations are still valid from a radio conditions perspective.

As the use case of UEs with burst traffic constantly being suspended and resumed in the same cell is quite typical, 3GPP has standardized a solution in LTE to enable the UE to assist the network with measurements performed while the UE is in RRCJDLE so that the network could speed up the setup of CA or DC. That solution is described below.

1.4 Existing Solution for Early Measurements upon Idle to Connected Transition in LTE (Release 15) !n LTE Release 15, it is possible to configure the UE to report so-called early measurements upon the transition from idle to connected State. These measurements are measurements that the UE can perform in idle State, and accordîng to a configuration provided by the source cell, The intention is for the source cell to receive these measurements immediately after the UE is connected such that the source cell can quickly set up CA and/or other forms of DC (e.g., EN-DC, MR-DC, etc.) without the need to first provide a measurement configuration (measConfig) to the UE in RRC_CONNECTED, as shown in previous sections, and then wait for hundreds of milliseconds untii first samples are collected and monitored and then the first reports are triggered and transmiüed to the network.

1.4.1 Measurement configuration for early measurements upon résumé in LTE

A first aspect of the existing solution, as standardized in E-UTRA 36.331, is described in 5.6.20 Idle Mode Measurements. The UE can receive these idle mode measurement configurations in the System information (System Information Block 5 (SIB5)) in the field MeasIdleConfîgSiB-rl5, indicatîng up to 8 cells or ranges of cell IDs on which to perform measurements. In addition, the UE can be configured, upon the transition from RRC_CONNECTED to RRCJDLE, with a dedicated measurement configuration in the RRCConnectionReiease message with the measidieDedicated-rî 5 which overrides the broadeasted configurations in SIB5. The broadeasted and dedicated signaling ss shown below:

RRCConnectionRelease message

- ASN1START

RRCConnectionRelease	SEQUENCE{
rrc-Transaciion Identifier	RRC-Transaciionïdeniifier,
criti cal Extensions	CHOICE {
cl	CHOICE {
rrcConnectionRelease-r8	RRCConnectionRelease-r8-IEs,

spare3 NULL, spare2 NULL, sparel NULL

}, critica! Exten sionsFutu re

SEQUENCE $

} }

-- other info has been omitted

RRCConnectionRelease-vl530-1 Es ::	= SEQUENCE{
drb-ContinueROHC-r15	ENUMERATED {true} OPTIONAL,
nextHopChainingCount-r15 Cond UP-EDT	NextHopChainingCount OPTIONAL,
measldieConfig-r15 OPTIONAL, - Need ON rrc-înactiveConfig-r15 Need OR	MeasldieConfîgDedicated-r15 RRC-lnactiveConfig-r15 OPTIONAL,
cn-Type-r15 OPTIONAL - Need OR nonCntrcalExtension	ENUMERATED {epc,fivegc} SEQUENCE {} OPTIONAL

}

- ASN1STOP

Meas/dleConfig information element

- ASN1START

MeasldleConfîgSIB-r15 ::= SEQUENCE { measidleCarrierListEUTRA-r15 EUTRA-CarrierList-r15, }

MeasldieConngDedicated-r15 :;= SEQUENCE { measldleCarnerListEUTRA-r15EUTRA-CarrierList-r15 OPTIONAL,

Need OR measldleDuration-r15 ENUMERATED {sec10, sec30, secGQ, sec 120, seçisû. seç24û, see300, spare}, }

EUTRA-CarnerList-r15 :;= SEQUENCE (SIZE (1..maxFreqldle-r15)) MeasldleCarrierEUTRA-r15	OF
MeasldleCarrierEUTRA-r15::= SEQUENCE { carnerFœq-r15 ARFCN-ValueEUTRA-r9, allowedMeasBandwidth-r1 5 AIlowedMeasBandwidth,
validityArea-r15 CeIILîst-r15 OPTIONAL, Need OR	—
measCellList-r15 CeliList-r15 OPTIONAL, Need OR reportQuantities ENUMERATED {rsrp, rsrq, both}, qua!ityThreshold-r15 SEQUENCE { idieRSRP-Threshold-r15 RSRP-Range OPTIONAL. - Need OR idleRSRQ-Threshold-r15 RSRQ-Range-r13 OPTIONAL- Need OR
} OPTIONAL, Need OR	—

}

CellList-r15 ::= SEQUENCE (SIZE (1.. maxCellMeasldle-r15)) OF PhysCelildRange

—	ASN1STOP
	MeasIdleConfig fieid descriptions i
	aflowedMeasBandwidth If absent, the value correspond ing to the downlink bandwidth indicated by the dfBandwidth included in MasterlnfonvationBlock of serving cell applies.
	carrierFœq Indicates the E-UTRA carrier frequency to be used for measurements during IDLE mode.
	measIdleCarrierListEUTRA Indicates the E-UTRA carriers to be measured during IDLE mode.
	measldieDuratÎQn Indicates the duration for performing measurements during IDLE mode for measurements assigned via RRCConnectîonRelease. Value secIO correspond to 10 seconds, value sec30 to 30 seconds and so on.
	quafifyThreshoid Indicates the qualîty thresholds for reporting the measured cells for IDLE mode measurements.
	reportQuantities Indicates which measurment quantifies UE is requested to report in the IDLE mode measurement report.
	measCelIList Indicates the list of cells which the UE is requested to measure and report for IDLE mode measurements.
	validityArea Indicates the list of cells within which UE is requested to do IDLE mode measurements. If the UE reselects to a cell outside this list, the measurements are no longer required.

Carrier information and cell list: The UE is provided with a list of carriers and optionally with a list of cells on which the UE shah perform measurements. The fieid sNonlntraSearch in SystemlnformationBlockType3 does not affect the UE measurement procedures in IDLE mode.

Timer T331: Upon the réception of that measurement configuration, the UE starts a timer T331 with the value provided in measIdleDuration, which can go from 0 to 300 seconds. The timer stops upon receiving RRCConnectionSetup, RRCConnectionRésumé which indicates a transition to RRC_CONNECTED. That concept exists to iimit the amount of time the UE perfomns measurements for that purpose of early measurements.

Vaiidity Area: Another concept introduced in the LTE Reîease 15 solution is a validity area, which comprises a list of Physicai Cell Identifies (PCls). The intention is to Iimit the area where CA or DC may be setup later when the UE resumes/sets up the connection, so the early measurements are somewhat useful for that purpose. If validityArea is configured and UE reselects to a serving cell whose PCI does not match any entry in validityArea for the corresponding carrier frequency, the timer T331 is stopped. Then, UE stops to perform IDLE measurements and reieases the configuration (i.e., VarMeasIdleConfig). Notice that this does not necessariiy imply that the UE reieases the idle measurements that were configured and that were performed, i.e. these may still be stored and possibiy requested by the network. In addition, the UE may continue with IDLE mode measurements according to the broadcasted S!B5 configuration after the timer T331 has expired or stopped.

Minimum quality threshold: Notice also that only measurements above a certain threshold shah be stored as the ce!! candidates for CA setup need to be within a minimum acceptable threshold. How the UE performs measurements in IDLE mode is up to UE implémentation as long as RAN4 requirements for measurement reporting defined in 36.133 are met.

The UE behavîor is shown below in more detail as captured in 3GPP TS 36.331 :

5.6.20 Idle Mode Measurements

5.6.20,1 General

This procedure spécifiés the measurements done by a LIE in RRCJDLE when it has an IDLE mode measurement configuration and the storage of the available measurements by a UE in boih RRCJDLE and RRC_CONNECTED.

5.6.20.2 Initiation

While T331 is running, the UE shaît

1> perform the measurements in accordance with the following:

2>foreach entry in measIdleCamerUstEUTRA within VarMeasIdleConffg:

3> if UE supports carrier aggregation between serving carrier and the carrier frequency and bandwidth indicated by canierFreq and allowedMeasBandwidth within the correspondsng entry;

4> perform measurements in the carrier frequency and bandwidth indicated by camerFreq and allowedMeasBandwidth within the corresponding entry;

NOTE: The fields s-Non IntraSearch in SystemlnformationBlockType3 do not affect the UE measurement procedures in IDLE mode. How the UE performs measurements in IDLE mode is up to UE implémentation as long as the requirements in TS 36.133 [16] are met for measurement reporting. UE is not required to perform idle measurements if SIB2 idle measurement indication is not configured.

4>ifthe measCellList is included:

5> consider PCel! and cells identifted by each entry within the measCellList to be applicable for idle mode measurement reporting;

4>else:

5> consider PCell and up to maxCellMeasldle strongest identified cells whose RSRP/RSRQ measurement results are above the value(s) provided in qualityThreshold (if any) to be applicable for idle mode measurement reporting;

4> store measurement results for cells applicable for idle mode measurement reporting within the VarMeasIdleReport,

3>else:

4>do not consider the carrier frequency to be applicable for idle mode measurement reporting;

> if validityArea is configured in VarMeasIdleConfîg and UE reselects to a serving cell whose physical cell identity does not match any entry in validityArea for the corresponding carrier frequency:

2> stop T331;

5.6.20.3 T331 expiryorstop

The UE shalï:

1> îf T331 expires or is siopped:

2> reiease the VarMeasIdleConfig;

NOTE: If is up to UE implémentation whether to continue IDLE mode measurements according to SIB5 configuration after T331 has expired or stopped.

Notice that it is not mandatoty for the source node releasing/suspending the UE to provide a dedicated idle measurement configuration for the purpose of early measurements. If the UE is released/suspended to idle without being provided with a list of carriers to be measured, the UE obtains that from SIB2, as written below:

1>if the RRCConnectionRelease message includes the measIdleConfig:

2> clear VarMeasIdleConfig and VarMeasIdleReport

2> store the received measIdleDuration in VarMeasIdleConfig;

2>start T331 with the value of measidieDuration;

2> if the measIdleConfig conta in s measIdleCarherListEUTRA:

3> store the received measIdleCamerListEUTRA in VarMeasIdleConfig;

2>else:

3> store the measld!eCarrierListFUTRA received in SIB5 in VarMeasIdleConfig;

2> start performing idle mode measurements as specified in 5.6.20;

And, in that case of the list not being provided in RRCConnectionRelease, at every cell reselection the UE performs the SIB5 acquisition to possibly update its list of carriers to measure as shown below:

5.2 .2.12 Actions upon réception of SystemlnformationBlockType5

Upon receiving SystemlnfarmationBlockType5, the UE shall:

1>if in RRCJDLE and UE has stored Va/7Vfeas/d/eConfig_and SIB5 includes the meas/dleConfïgSiB and the UE is capable of IDLE mode measurements for CA:

2> if T331 is running and VarMeasldfeConfig does not contain measldleCarnerLsstE'JTRA received from the RRCConneciionReleasa message:

3> store the measIdleCamertistEUTRA of measIdleConfigSIB within VarMeasIdle Config·,

2> perform idle mode measurements on supported carriers as specîfied in 5.6.20;

If the UE enters a cell within the validity area that is not broadcasting the measurement configuration in S1B5, the UE continues to perfomn idle measurements according to the S1B5 acquired in the source cell (i.e., the cell the UE was suspended or released).

1.5 RRCINACTIVE in N R and possible in L TE Release 15

As part of the standardized work on 5G NR in 3GPP, it has been decided that NR should support an RRCJNACTIVE state with similar properties as the suspended State in LTE Release 13. The RRCJNACTIVE has slightly different properties from the late State in that it is a separate RRC State and not part of RRCJDLE as in LTE. Additionally, the CN/RAN connection (NG or N2 interface) is kept for RRCJNACTIVE whîle it was suspended in LTE. Figure 6 shows possible State transitions in NR.

The properties of the States shown in Figure 6 are as foliows:

. RRCJDLE:

o A UE spécifie Discontinuous Réception (DRX) may be configured by upper layers;

o UE Gontrolled mobility based on network configuration;

o The UE:

Monitors a paging channel for CN paging using 5G System Architecture Evolution Temporary Mobile Subscriber Identity (STMSi);

Performs neighboring cell measurements and cell (re-)selection;

Acquires System information.

• RRCJNACTIVE:

ο A UE spécifie DRX may be configured by upper layers or by RRC layer;

o UE controlled mobility based on network configuration;

o The UE stores the AS context;

o The UE:

• Monitors a paging charme! for CN paging using 5G-S-TMSI and RAN paging using Inactive Radio Network Temporary Identifier (lRNTI);

Performs neighboring cell measurements and cell (re-) sélection;

Performs RAN-based notification area updates periodically and when moving outside the RAN-based notification area;

- Acquîtes System information, • RRC_CONNECTED:

o The UE stores the AS context;

o Transfer of unicast data to/from UE;

o At lower layers, the UE may be configured with a UE spécifie DRX;

o For UEs supporting CA, use of one or more SCeüs, aggregated with the Spécial Cell (SpCell), for increased bandwidth;

o For UEs supporting DC, use of one SCG. aggregated with the MCG, for increased bandwidth;

o Network controlled mobility, i.e. handover wîthin NR and to/from EUTRAN;

o The UE:

« Monitors a paging channel;

Monitors control channels associated with the shared data channel to détermine if data is scheduled for it;

• Provides channel quality and feedback information;

- Performs neighboring cell measurements and measurement reporting;

Acquires System information.

1.6 Introducing of eariy measurements upon idle/inactive to connected transition in NR (Reiease 16)

A work item has been approved in Reiease 16 to enhance the setup of CA/DC in NR. The Work Item Description (WID) “Enhancing CA Utilization” was approved in RAN#80 in RP-181469 and updated in RAN#81 in RP-182076, and one ofthe objectives is the following;

Early Measurement reporting: Early and fast reporting of measurements information availability from neighbor and serving cells to reduce delay settîng up MR-DC and/or CA. [RAN2, RAN4] o This objective applies to MR-DC, NR-NR DC and CA o The objective should consider measurements in IDLE, INACTIVE mode and CONNECTED mode o The impacts on UE power consomption should be minimized o The LTE Rei-15 euCA work should be utilized, when applicable

Hence, 3GPP is going to investigate solutions to enable early measurements performed when the UE is in RRCJNACTIVE or RRC_IDLE State and reporting mechanisms for when the UE enfers RRC_CONNECTED.

Based on contributions submitted to RAN2#105 to Athens, three different kinds of solutions are going to be considered:

1. UE reports early measurements in UEInformationResponse after a request from a network in U El nformation Request is transmitted after the UE sends an RRCResumeComplete/RRCConnectionResumeComplete, or after security is activated when the UE cornes from idle without stored context;

2. UE reports early measurements with (e.g., multiplexed with or as part of the message)

RRCResurneComplete/RRCCûnneciiûnResumeCompleté/RRCSëtupComplëÎè/R RCConnectionSetupComplete/SecurityModeComplete, etc.;

3. UE reports early measurements with (e.g., multiplexed with or as part of the message)

RRCResumeRequest/RRCConnectionResumeRequest/RRCSetupRequest/RRC ConnectionSetupRequest.

There are some différences in details of each of these solutions, and not ail of them may be applicable for RRCJDLE in the same way they are for RRCJNACTIVE. However, in any of these solutions for the reporting, the UE relies on a measurement configuration, which may be provided with dedicated signaling when the UE is suspended to RRCJNACTIVE or when the UE is released to RRCJDLE. That measurement configuration indicates how the UE is to perform these measurements to be reported when the UE résumés (in the case of coming from RRCJ N ACTIVE or sets up a connection, in the case of coming from RRCJDLE).

Problems with Existing Solutions

The currently exist certain challenge(s). In regard to inter-RAT cell sélection in RRCJDLE or RRCJNACTIVE, according to current RRC spécifications (3GPP TS 38.331 Rel-15, V15.4.0 (2018-12)), a UE in RRCJNACTIVE, which re-se!ects to an interRAT cell will transition to RRCJDLE. Specifically, the UE behavior in NR RRCJNACTIVE according to 3GPP TS 38.331 is: 5.3.13.12 Inter RAT cell reselection

Upon reselecting to an inter-RAT cell, the UE shall;

1> perform the actions upon going to RRCJDLE as specified in 5.3.11, with reiease cause 'other¹.

Similarly, the UE behavior in E-UTRA/5GC RRCJNACTIVE according to 3GPP TS 36.331 is:

5.3.17.3 Inter RAT cell reselection or CN type change

Upon reselecting to an inter-RAT ceïl or to another CN type, the UE shall:

1> perform the actions upon leaving RRCJNACTIVE as specified in 5.3.12, with releass cause 'other*.

UE behavior in E-UTRA RRCJNACTIVE according to 3GPP TS 36.304~ïs:

5.2.4.11 Cell reselection when storing UE AS context

For UEs storing UE AS context and resumeldentity as specified in TS 36.331 [3], upon cell reselection to another RAT, the UE shall discard the stored UE AS context and resumeldentity.

It is not clear the UE behavior should be regarding idle/inactive measurements when the UE re-selects to an inter-RAT cell assuming the existing inter-RAT re-selection handling solution. The reason is that, if the UE is in RRCJNACTIVE, the UE will transition to RRCJDLE and reiease the UE inactive AS Context, which is also known as UE AS Context in E-UTRA. In LTE, where the idle measurement configuration/reporting has been specified, it is not clear how the idle measurement configurations and resuIts are handled, which can cause ambiguity between the behavior of the UE and that of the network (e.g., the UE may keep the measurement configurations/resuIts. whiie network expects the UE to reiease them).

Summary

Systems and methods are disclosed herein that relate to handling of dormant state (e.g., IDLE/INACTIVE State) measurement configurations and associated measurements upon inter-Radio Access Technology (RAT) cell reselection in a cellular communications System. Embodiments of a method performed by a wireless device and corresponding embodiments of a wireless device are disclosed. In some embodiments, a method performed by a wireless device comprises receiving one or more dormant State measurement configurations from a network node of a source RAT, performing measurements white in a first dormant State in accordance with at least one of the one or more dormant State measurement configurations, and performing an inter-RAT cell reselection from the source RAT to a target RAT while in the first dormant State. The method further comprises, upon performing the inter-RAT cell reselection from the source RAT to the target RAT while in the first dormant State, performing one or more actions to handle dormant State measurement configurations, to handle early measurements performed in accordance with dormant State measurement configurations, or to handle both dormant state measurement configurations and measurements performed in accordance with dormant state measurement configurations.

In some embodiments, the one or more dormant state measurement configurations comprise one or more dormant state measurement configurations for the source RAT of the wireless device, and the one or more actions comprise stopping performance of measurements made in accordance with the one or more dormant state measurement configurations for the source RAT. in some embodiments, stopping performance of early measurements made in accordance with the one or more dormant state measurement configurations for the source RAT comprises stopping a timer that limits an amount of time that the wireless device is to perform measurements in accordance with the one or more dormant state measurement configurations for the source RAT. In some embodiments, stopping performance of measurements made in accordance with the one or rnore dormant state measurement configurations for the source RAT comprises releasing the one or more dormant State measurement configurations for the source RAT. In some embodiments, the one or more actions further comprise transitioning to a second dormant state in the target RAT.

In some embodiments. the one or more actions comprise stopping performance of measurements made while in a dormant state.

In some embodiments, at least one of the one or more actions is configured by the network node.

In some embodiments, the one or more dormant state measurement configurations received from the network node comprise one or more dormant state measurement configurations for measuring on cetis, frequencies, and/or beams associated with the source RAT. In some embodiments, the one or more dormant state measurement configurations received from the network node comprise one or more dormant state measurement configurations for measuring on cells, frequencies, and/or beams associated with the target RAT. In some embodiments, the one or more dormant state measurement configurations received from the network node comprise one or more dormant State measurement configurations for measuring on ceils, frequencies, and/or beams associated with the source RAT and the target RAT.

In some embodiments, the method further comprises reporting the early measurements to a target RAT network node.

In some embodiments. a wireless device is adapted to receive one or more dormant state measurement configurations from a network node of a source RAT, perform measurements while in a first dormant state in accordance with at least one of the one or more dormant state measurement configurations, and perform an inter-RAT cell reselection from the source RAT to a target RAT while in the first dormant state. The wireless device is further adapted to, upon performing the inter-RAT cell reselection from the source RAT to the target RAT while in the first dormant State, perform one or more actions to handle dormant state measurement configurations, to handle measurements performed in accordance with dormant state measurement configurations, or to handle both dormant state measurement configurations and measurements performed in accordance with dormant state measurement configurations.

In some embodiments, the wireless device comprises one or more transmitters, one or more receivers, and processing circuitry associated with the one or more transmitters and the one or more receivers. The processing circuitry is configured to cause the wireless device to receive the one or more dormant state measurement configurations from the network node of the source RAT, perform the measurements while in the first dormant state in accordance with the at least one of the one or more dormant state measurement configurations, perform the inter-RAT cell reselection from the source RAT to the target RAT while in the first dormant state, and, upon performing the inter-RAT cell reselection from the source RAT to the target RAT while in the first dormant State, perform the one or more actions to handle dormant State measurement configurations, to handle measurements performed in accordance with dormant state measurement configurations, or to handle both dormant state measurement configurations and measurements performed in accordance with dormant State measurement configurations.

Embodiments of a method performed by a base station are also disclosed. In some embodiments, a method performed by a base station using a source radio RAT composes providing one or more dormant state measurement configurations to a wireless device in the source RAT and providing, to the wireless device, information that indicates one or more actions to be performed by the wirele-ss device upon inter-RAT cell reselection from the source RAT to a target RAT while in a dormant State in order to handle measurements performed in accordance with dormant State measurernent configurations, or to handle both dormant State measurernent configurations and measurements performed in accordance with dormant state measurernent configurations.

In some embodiments, the one or more dormant State measurernent configurations provided to the wireless device comprise one or more dormant State measurernent configurations for measuring on cells, frequencies, and/or beams associated with the source RAT, one or more dormant state measurernent configurations for measuring on cells, frequencies, and/or beams associated with the target RAT, or one or more dormant state measurernent configurations for measuring on cells, frequencies, and/or beams associated with the source RAT and the target RAT.

in some embodiments, tne one or more actions comprise any one or combination of the following actions: transitioning to a second dormant state in the target RAT; stop performing measurernent according to one or more source RAT measurernent configurations, the one or more source RAT measurernent configurations being comprised in the one or more dormant state measurernent configurations; stop performing early measurements; releasing current measurements performed according to the one or more dormant state measurernent configurations.

Corresponding embodiments of a base station are also disclosed. In some embodiments, a base is adapted to provide one or more dormant state measurernent configurations to a wireless device using a source RAT and provide, to the wireless device, information that indicates one or more actions to be performed by the wireless device upon inter-RAT cell reselection from the source RAT to a target RAT while in a dormant state in order to handle measurements performed in accordance with dormant state measurernent configurations, or to handle both dormant state measurernent configurations and measurements performed in accordance with dormant state measurernent configurations.

In some embodiments, the base station comprises Processing circuitry configured to cause the base station to provide the one or more dormant state measurernent configurations to the wireless device using the source RAT and provide, to the wireless device, the information that indicates the one or more actions to be performed by the wireless device upon inter-RAT cell reselection from the source RAT to the target RAT while in a dormant state in order to handle measurements performed in accordance with dormant state measurernent configurations, or to handle both dormant state measurernent configurations and measurements performed in accordance with dormant state measurernent configurations.

Brief Description of the Drawings

The accompanying drawîng figures ïncorporated in and forming a part of this spécification iilustrate several aspects of the disclosure, and together with the description serve to expia in the principles of the disclosure.

Figure 1 illustrâtes the operation of the Medium Access Control (MAC) layer for Carrier Aggregation (CA);

Figure 2 illustrâtes transitions between three User Equipment (UE) States in Long Term Evolution (LTE);

Figure 3 illustrâtes a conventional process in which the network décidés to setup CA or Dual Connectivity (DC) for a UE;

Figure 4 shows interconnections between base stations and other base stations and core network nodes in a Fifth Génération (5G) System (5GS),

Figure 5 illustrâtes different ways to deploy a 5G network with or without interworking with LTE;

Figure 6 shows possible State transitions for a UE in 5G New Radio (NR);

Figure 7 illustrâtes one example of a cellular communications System in which embodiments of the présent disclosure may be implemented;

Figure 8 is a flow chart that illustrâtes the operation of a UE in accordance with embodiments of the présent disclosure;

Figure 9 is a flow chart that illustrâtes the operation of a base station in a source Radio Access Technology (RAT) of an inter-RÀT ceii reseiection for a UE in accordance with some embodiments of the présent disclosure;

Figure 10 is a flow chart that illustrâtes the operation of a base station in a target RAT of an inter-RAT cell reseiection for a UE in accordance with some embodiments of the présent disclosure;

Figures 1 1 through 13 are schematic block diagrams of example embodiments of a radio access node, such as a base station;

Figures 1 4 and 15 are schematic block diagrams of example embodiments of a UE;

Figure 16 illustrâtes another example of a System in which embodiments of the présent disclosure may be implemented;

Figure 17 iîîustrate example embodiments of the host computer, base station, and UE in the System of Figure 16;

Figures 1 8 through 21 are flowcharts illustrating method implemented in a communication system, in accordance with some embodiments of the présent disclosure.

Detailed Description

The embodiments set forth beiow represent information to enabie those skilled in the art to practice the embodiments and iîlustrate 8» best mode of practicing the embodiments. Upon reading the following description in light of the accompanying drawing figures, fri ose skiiled in ths art wi8 undsrstand ihe concepts of the disclosure and will recognize applications of these concepts not particularly addressed herein. It should be understood that these concepts and applications fall within the scope of the disclosure.

Radio Node: As used herein, a “radio node is either a radio access node or a wireless device.

Radio Access Node: As used herein, a “radio access node’’ or “radio network node” is any node in a Radio Access Network (RAN) of a cellular communications network that opérâtes to wirelessly transmit and/or receive signais. Some examples of a radio access node include, but are not limited to, a base station (e.g., a New Radio (NR) base station (gNB) in a Third Génération Partnership Project (3GPP) Fifth Génération (5G) N R network or an enhanced or evolved Mode B (eNB) in a 3GPP Long Term Evolution (LTE) network), a high-power or macro base station, a iow-power base station (e.g., a micro base station, a ptco base station, a home eNB, or the like), and a relay node,

Core Network Node: As used herein, a “core network node” is any type of node in a Core Network (CN) or any node that impiements a core network fonction. Some examples of a core network node include, e.g., a Mobility Management Entity (MME), a Racket Data Network Gateway (F-GW), a Service Capabiüty Exposure Function (SCEF), a Home Subscriber Server (HSS). or frie like. Some other examples of a core network node include a node implementing an Access and Mobility Management Function (AMF), a User Plane Function (UPF), a Session Management Function (SMF), an Authentication Server Function (AUSF), a Network Slice Sélection Function (NSSF), a Network Exposure Function (NEF), a Network Reposiîory Function (NRF), a Policy Control Function (PCF), a Unified Data Management (UDM), or the like.

Wireless Device: As used herein, a hwireless device” is any type of device that has access to (i.e., is served by) a cellular communications network by wirelessly transmitting and/or receiving signais ίο a radio access node(s). Some examples of a wireless device include, but are not limited to, a User Equipment (UE) in a 3GPP network and a Machine Type Communication (MTC) device.

Network Node: As used herein, a “network node” is any node that is either part of the RAN or the core network of a cellular communications network/system.

Note that the description given herein focuses on a 3GPP cellular communications System and, as such, 3GPP termînology or temninology similar to 3GPP terminology is oftentimes used, However, the concepts disclosed herein are not limited to a 3GPP System.

Note that, in the description herein. référencé may be made to the term ceir; however, particulariy with respect to 5G NR concepts, beams may be used instead of cells and, as such, it is important to note that the concepts described herein are equaily applicable to both cells and beams.

Embodiments of the present disclosure apply to the case where a UE performs inter-Radio Access Technology (RAT) and or inter-system cei! reselectîon while in a dormant State (e.g., LTE/NR IDLE, LTE/NR INACTIVE, LTE ÎDLE with suspended). The example embodiments described be'ow are mostly regarding the handling of idle/inactive measurements during an inter-RAT cell reselectîon while in dormant State in NR. However, the embodiments described herein are equaily applicable to LTE (e.g., LTE IDLE, LTE IDLE with suspended, LTE INACTIVE).

In the example embodiments, the term source RAT and source node refer to the RAT and network node respectively which the UE was connected to when it was reieased to the dormant State. Sîmilariy, the term target RAT and target node refer to the RAT and network node in which the UE re-selects to while in the dormant State.

The term source RAT and target RAT should also be considered to represent the case wnere the source RAT and target RAT are of the santé type, but connected to different core networks, i.e. Evolved Universal Terrestrial Radio Access (E-UTRA) connected to Evolved Packet Core (EPC) or E-UTRA connected to 5G Core (5GC).

The terms node, cell, and RAT are used interchangeably when refemng to a source or target node/cell/RAT.

It should be noted that the UE behavior can either be configured by the network via broadcasted or dedicated signaling, or specified in the standards (here we cover the details of the case where the network configures the UE behavior).

Certain aspects of the present disclosure and their embodiments may provide solutions to the aforementioned challenges related to idie mode measurements and interRAT reselectîon or other challenges. The present disclosure provides embodiments of a UE and a network node and correspond!ng embodiments of methods of operation of a UE and a network node that handîe idle/inactive measurements when the UE performs inter-RAT reseleciion. Several options are proposée! on how to handie the previous measurement configurations and resuits, namely:

• reiease both the measurement configurations and resuits, or • release the measurement configuration but keep the resuits, • keep the measurement configuration but cîear the resuits, or • keep both the measurement configuration and the resuits.

In case the measurement configurations and/or resuits are kept when moving from one RAT to another RAT, the format and content of the configurations and/or resuits may be adapted, converted, or modified to match the specified format of the target RAT.

Some sub-cases and combinations of the above are also possible, as described below (e.g., keeping only part of the previous measurement configuration and/or resuits).

Embodiments of the présent disclosure résolve the ambiguity regarding the idle/inactive measurements configurations and resuits when a UE performs inter-RAT cell re-selection and provide flexible mechanisms where the network can configure the UE to keep or release idle/inactive measurement configurations and/or resuits to the target RAT (or UE behavior specified in the standards).

Embodiments of the présent disclosure further allow the UE to adapt the idle/inactive measurement configurations and/or resuits from the source RAT to the target RAT configuration or format in order to ensure the idle/inactive measurement resuits can be reported in the target RAT in a format the target RAT can interpret.

Certain embodiments may provide one or more of the following technical advantage(s). For exampie, in LTE, even though the idle measurement configuration and early measurement reporting hâve been specified, the behavior when the UE performs inter-RAT cell reseleciion is not fully specified. This could lead to the network expecting the UE to behave in one way whiïe the UE behaves in another (e.g., ihe network expects the UE to keep measuring based on previous configurations, while the UE releases the measurement configurations/results or vice versa), tf the LTE solutions are adopted in NR, the same issue will be carried over to NR. Embodiments of the présent disclosure résolve this ambiguity and provide flexible mechanisms where the network can configure the UE to keep or release idle/inactive measurement configurations and/or resuits (or UE behavior specified in the standards).

In this regard, Figure 7 illustrâtes one example of a cellular communications System 700 in which embodiments of the présent disclosure may be implemented. fn the embodiments described hêrein, the cellular communications System 700 is an LTE or 5G NR network. ]n this example, ihe cellular communications System 700 includes a radio access network including base stations 702Ί and 702-2, which in LTE are referred to as eNBs and in 5G N R are referred to as gNBs, contrai ling correspond ing macro cells 704-1 and 704-2. The base stations 702-1 and 702-2 are generalîy referred to herein collectiveiy as base stations 702 and individually as base station 702. Likewise, the macro cells 704-1 and 704-2 are generalîy referred to herein collectiveiy as macro cells 704 and individually as macro cell 704. The radio access network of the cellular communications System 700 may also include a number of low power nodes 706-1 through 706-4 controlling corresponding small cells 708-1 through 708-4. The low power nodes 706-1 through 706-4 can be small base stations (such as pico or femto base stations) or Remote Radio Heads (RRHs), or the like. Notably, while not illustrated, one or more of the small cells 708-1 through 708-4 may alternative^ be provided by the base stations 702. The low power nodes 706-1 through 706-4 are generalîy referred to herein collectiveiy as low power nodes 706 and individually as low power node 706. Likewise, the small cells 708-1 through 708-4 are generalîy referred to herein collectiveiy as small cells 708 and individually as small cell 708. The cellular communications system 700 also includes a core network 710 to which the base stations 702 (and optionally the low power nodes 706) are connected.

The base stations 702 and the low power nodes 706 provide service to wireless devices 712-1 through 712-5 in the corresponding cells 704 and 708. The wireless devices 712-1 through 712-5 are generalîy referred to herein collectiveiy as wireless devices 712 and individually as wireless device 712. The wireless devices 712 are also sometimes referred to herein as UEs.

Now, the discussion will turn to details regarding some example embodiments of the présent disclosure. These examp le embodiments are described with respect to LTE and NR and, as such, LTE and NR terminology is oftentimes used. Note, however, the présent disclosure is not limited to LTE and NR. Rather, the embodiments described herein may be implemented in any suitable type of wireless communication System.

UE Embodiments

Embodiments of a method executed by the UE for the handling of inactive/idle measurement configuration the UE appiies during a dormant State (LTE/NR IDLE, LTE IDLE with suspended, LTE/NR INACTIVE), specifically upon perfomning inter-RAT cell reselection, are disclosed herein. In some embodiments, as illustrated in Figure 8, the method executed by the UE includes:

• Step 800: The UE reçoives a measurement CQnfiguration(s) in a source RAT to perform idle/inactive measurement configurations (e.g., via RRCRelease, RRCConnectionRelease, system information broadcast, etc.). Unis measurement configuration(s) is aiso referred to herein as a dormant state measurement configuration, a dormant State early measurement configuration, or a power saving state measurement configuration.

o In one sub-variant the UE is configured to measure on cells, frequencies, and/or beams associated with foe source RAT, o In one sub-variant, the UE is configured to measure on cells, frequencies, and/or beams associated with the target RAT;

o In one sub-variant, the UE is configured to measure on cells, frequencies, and/or beams associated with the source RAT and the target RAT.

• Step 802 (Optional): The UE enters a dormant state and starts a timer (e.g., T331) or keeps the timer running.

• Step 804: While in the dormant state (and while the timer is running), the UE performs dormant state early measurements (i.e., idle/inactive state or mode measurements) in accordance with the measurement configu ratio n(s).

• Step 806 (Optional): The UE décidés to perform inter-RAT cell reselection based on idle/inactive mode cell reselection procedures.

• Step 808: The UE performs inter-RAT cell reselection.

• Step 810: Upon performing the inter-RAT ce!! reselection procedure while performing idle/inactive measurements, the UE performs one or more actions to handle dormant state measurement configu ration (s) and/or dormant state measurement results with respect to the inter-RAT reselection. These one or more actions may include any one or any combination ofthe following:

o In one variant, the UE remains in the same power saving state (e.g., RRCJNACTIVE, RRCJDLE with suspended RRC Connection, RRCJDLE without suspended RRC Connection, etc.). Note that the terms power saving state and dormant state are used interchangeably herein.

o In another variant, the UE transitions to another power saving state (e.g., RRCJNACTIVE, RRCJDLE with suspended RRC Connection, RRCJDLE without suspended RRC Connection).

o In one variant related to the idle/inactive measurement configurations (C1):

The UE stops performing idle/inactive measurements according to the source RAT configuration.

This includes stopping ail actions related to early inactive/idle measurements, such as stopping rimer T331, stopping performing measurements, releasing the measurement configurations for early idle/inactive measurements, etc.

In one sub-variant, if the target RAT has provided an idle/inactive mode measurement configuration via System information broadcast, the UE applies these configurations and starts performing idle measurements accordingly.

« in one sub-variant, the UE will not perform idie measurements anymore, even if the target RAT has provided an idle/inactive mode configuration via System information broadcast.

o in another variant reiated to the idie/inactive measurement configurations (C2):

» The UE keeps performing the early measurements according to the previous idle/inactive measurement configurations.

in one sub-variant, the UE keeps a subset of the measurement configurations and continues measuring according to these configurations. - This could be measurements that are relevant only while camping at the target RAT (e.g., if the cell sélection was from NR to LTE, only keep measurement configurations at the cell îevel instead of beam level on NR frequencies after the cell reselection); and/or The UE keeps a subset of the measurement configurations that are relevant to the IDLE mode (e.g., reiated to beam measurements and/or CS1-RS measurements, that are relevant to the INACTIVE mode but not to the IDLE mode; and/or

In another sub-variant, the UE keeps the ancillary configuration parameters such as the validity area, idieMeasDuration, etc.

• The UE may not restart the timer T331 (e.g., if the timer in the source RAT was set to x seconds, and the UE performs ths interRAT reselection after y seconds, the UE will keep running the timer for an extra x-y seconds after the ceH reselection, or it will start a new timer with a value of x-y seconds upon cell reselection.

* The UE may restart the timer T331 with the initial value configured in the source RAT.

In one sub-variant, if the target RAT has provided an idle/inactive mode measurement configuration via System information broadcast, the UE applies these configurations on top of the previous configuration from the source RAT (or whatever configurations were decided to be kept according to the sub-variants above) (i.e., delta configuration).

In one sub-variant, the UE keeps the idle measurements configurations (or whatever configurations were decided to be kept according to the su b variants above) only if the target RAT has not provided an idle/inactive mode measurement configuration via system information broadcast.

o In one variant, the UE couverts the configurations provided by the source RAT to the format of the target RAT and starts the idle/inactive measurements according to the target RAT.

In one sub-variant, the source RAT indicates ta the UE how to convert the measurement configurations if the UE re-selects to an inter-RAT cell

In another sub-variant, the target RAT indicates to the UE how to convert the measurement configurations, when the UE re-selects ta an inter-RAT cell.

o In one variant related to the idle/inactive measurement results (R1):

³ The UE releases the current measurement results performed according to the source RAT.

in one sub-variant, such a release of the measurement results is performed only if the target RAT has provided an idle/inactive mode measurement configuration via system information broadcast.

in one sub-variant, such a release of the measurement results is performed even if the target RAT has not provided an idle/inactive mode measurement configuration via system information broadcast.

o In another variant related to the eariy measurement results (R2):

• In one sub-variant (R2-1), the UE keeps the current measurement results regardless of the handling of the current measurement configurations (i.e., both for cases C1 orC2 above).

- In another sub-variant (R2-2), the UE keeps the current measurement results only if the handling of the measurement configurations is such that the current configurations are kept (i.e., only for C2 above).

In another sub-variant (R2-3), the UE keeps the current measurement results only if the handling of the measurement configurations is such that the current configurations are kept and the timerT331 is not restarted.

In another sub-variant (R2-4), the UE keeps the current measurement results only if the handling of the measurement configurations is such that the current configurations are kept whether the timer T331 is restarted or not.

In one sub-variant (R2-5), the UE releases a subset of the measurement results, e.g. reiated to beam measurements and/or CSI-RS measurements, that are relevant to the INACTIVE mode but not to the IDLE mode. The LIE will keep the remaining measurement results.

In one sub-variant (R2-6), the UE releases a subset of the measurement results, e.g. reiated to beam measurements and/or CSI-RS measurements, that are relevant to the source RAT but not to the target RAT. The UE will keep the remaining measurement results.

if the decision by the UE was to keep the oid measurement results:

The new and the old measurement results are kept in the same UE parameter (e.g., VarMeasldleReport if the target RAT is E-UTRA); or The new and old measurement results are kept in different UE parameters (e.g., if the source RATwas E-UTRA and the target RAT Is NR, the previous results will be kept îû a UE variable (e.g., VarMeasldleReport) and the new results can be kept in another variable (i.e., VarMeasIdlelnactiveReport); or

Some of the old measurements are converted to the target RAT format kept with the new measurements în one UE parameter (e.g., VarMeasldleReport), and the rest of the old measurements are kept in another UE variable (e.g., VarMeasIdlelnactiveReport); or

Some of the old measurements are converted to the target RAT format kept with the new measurements in one UE parameter (e.g., VarMeasldleReport), and the rest of the old measurements are released.

* Step 812 (Optional): Upon establishing a connection from RRC_IDLE or resuming a connection from RRCJNACTIVE or RRC_IDLE with suspend, the UE reports the avaîlable (if any) idie/inactive measurements usîng procedures applicable for eariy measurement reporting in RRCJDLE or RRCJNACTIVE.

o In one sub-variant, if the target and source RAT measurement configurations are different and/or if the IDLE and INACTIVE measurement configurations are different and the configuration of the UE was so that the UE keeps the measurements performed in the source and target RATs, then the eariy measurement reporting signaling is enhanced to include the measurements performed in the source and target RATs, and/or in the INACTIVE and IDLE states.

ο In one sub-variant, the UE indicates the availability of measurements belonging to the source and target RAT with a single indication.

o In another sub-variant, the UE indicates the availability of measurements belonging to the source and target RAT using separate indications.

o In another sub-variant, the UE does not indicate the availability of measurements, but the network can request the measurements blindly or usina information about the UE configuration.

in one alternative, upon establishing a connection from a dormant State, the UE indicates that it has a certain idle/inactive measurement configuration, e.g. from one or several spécifie RAT(s), and/or measurement results based on such idle/inactive measurement configuration (s) avaiîabie. The network then indicates to the UE through dedîcated signaling (as part of the procedure to estabiish/resume the connection) whether to maintain or release each such available idle/inactive measurement configuration and/or whether to provide (or not) the corresponding measurement result(s). The network can also indicate to the UE through such dedîcated signaling whether the UE should continue the measurements, e.g. whether to keep at least parts of the idle/inactive measurement configuration and keep the duration timer (e.g., T331) running, or alternatives restarting the duration timer.

It should be noted that the above behavior (e.g., C1/C2 with regard to idle/inactive measurement configurations and/or R1/R2 regarding the idle/inactive measurement results) can be configured by the network (e.g., in RRCReiease, via System Information Block (S!B) signaling, etc.) or via specified behavior in the standards.

An alternative method is for the UE to be configured with separate source and target RAT idle/inactive measurement configurations and when the UE performs interRAT cell reselection, it releases the source RAT measurement configurations/results and applies the target RAT idle/inactive measurement configurations.

As an alternative in the above variants, the behavior, i.e. whether to keep or release an idle/inactive measurement configuration and/or related measurements, is dépendent on to what RAT, carrier, and/or cell the UE has reseîected. The configuration that the UE has received can then indicate what behavior to apply for different RATs, carriers and/or cells, where different behaviors can be indicated for different RATs, carriers and/or cells. As an exampie, the idie/inactive measurement configuration that the UE receives in, e.g., an RRCConnectîonRelease message (in LTE) may include indications that the UE shall keep the early measurement configuration and measurements if it moves to an NR carrier X, whereas it shall release the early measurement configuration and measurements if it moves to another N R carrier Y.

Network Embodiments

Embodiments of a method executed by the network node (e.g., a base station 702 such as, e.g., a gNB (NR) or eNB (LTE)) for the handling of inactive/idle measurement configuration the UE applies during a dormant State (LTE/NR IDLE, LTE IDLE with suspended, LTE/NR INACTIVE), specifically when the UE performs inter-RAT cell reselection while in dormant State performing dormant state measurements, are disclosed herein. In some embodiments. as illustrated in Figure 9, the method executed by a source RAT network node includes:

• Step 900: The network node in a source RAT provides a configuration to a UE to perform idle/inactive measurement configurations (e.g., RRCRelease, RRCConnectionRelease, System information broadcast, etc ).

o In one sub-variant, the network configures the UE with measurement configurations for cells/frequencies/beams associated with the source RAT.

o In one sub-variant, the network configures the UE with measurement configurations for cells/frequencies/beams associated with the target RAT.

o In one sub-variant, the network configures the UE with measurement configurations for cells/frequencies/beams associated with the source RAT and the target RAT.

• Step 902 (Optional): The network node configures the UE with îdle/inactive measurement configurations handling in case the UE performs inter-RAT cell reselection, while in dormant State (C1). in other words, the network node configures the UE to perform one or more actions to handle dormant State measurement configurations and/or dormant State measurements in the case of inter-RAT cell reselection while in dormant State. The configuration of the one or more actions may include any one or any combination of the following;

o In one sub-variant, the network configures the UE to reiease the oid idle/inactive measurement configurations and stop Idle/inactive measurements.

o In another sub-variant, the network configures the UE to obtain full idle/inactive measurement configurations from the target RAT cell.

o in another sub-variant, the network configures the UE to keep the old idle/inactive measurement configurations.

In one sub-variant, the network configures the UE to keep a subset of the old measurement configurations.

This could be measurements that are relevant only while camping at the target RAT (e.g., if the cel! sélection was from N R to LTE, only keep measurement configurations at the cell level instead of beam level on NR frequencies after the cell reselection); and/or

This could be a subset of the measurement configurations that are relevant to the IDLE mode (e.g., retated to beam measurements and/or CSI-RS measurements, that are relevant to the INACTIVE mode but not to the IDLE mode; and/or

- This could be ancillary configuration parameters such as the validity area, idleMeasDuration, etc

In another sub-variant, the network configures the UE to obtain idie/inactive measurement configurations from the target RAT ceil which are applied on top of the old configurations.

In some embodiments, as illustrated in Figure 10, the method executed by a target RAT network node includes:

« Step 1000: The target RAT network node receives an establishment or résumé request from the UE in the target RAT.

• Step 1002: Upon receiving an establishment or résumé request from UE, the target RAT network node sends a request to the UE that requests that the UE report early measurements. More specificaîly, some example variants are as follows:

o In one variant, the establishment or résumé requests include an indication that the UE has early measurements to report. Upon receiving the establishment or résumé request including this indication, the target RAT network node sends a request to the UE to request for the UE to report early measurements. In a sub-variant, the establishment or résumé request includes separate indications for the source RAT and the target RAT measurements.

In one sub-variant, the target network node sends a request for the early measurements from the UE based on the indication from the UE for;

ail early measurements available; or only the eariy measurements from the RAT which the UE has indicated; or only the eariy measurements from the target RAT; or

- only the eariy measurements from the source RAT.

o In another variant, the target RAT network node sends a message to the source RAT network node to request a UE context of the UE with the idie/inactive measurement configurations. The se idie/inactive measurement configurations may be for the source RAT and/or the target RAT. in some embodiments, the target RAT network nodes send the request to the (JE to report eariy measurements based on the received UE context.

In a sub-variant, the UE context oniy contains measurement configurations for one of the RATs (source or target RAT).

In another sub-variant, the target network node sends a request for the early measurements from the UE based on the information in the UE context received from the source node:

If the UE context contains any idie/inactive measurement configurations, the target network node requests:

• all early measurements; or • early measurements associated with the source RAT; or • early measurements associated with the target RAT.

If the UE context contains any idie/inactive measurement configurations for only the source RAT or if the UE context contains any idie/inactive measurement configurations for only the target RAT, the target network node requests:

• all early measurements; or • only the early measurements associated with the source RAT; or • only the early measurements associated with the target RAT.

if the UE context contain configurations for early measurements for both the source and target RAT, the target network node requests:

• all early measurements; or • only the early measurements associated with the source RAT; or • only the early measurements associated with the target RAT.

o in another variant, the network has no indication that the UE has early measurements to report, but the network requests the idie/inactive measurements blindly.

o In another sub-variant, the target network node sends a request for the early measurements from the UE based on which RAT types can be configured and signaled in the early measurement report:

If the source RAT and the target RAT support configuring the same idie/inactive measurement configurations for both the source RAT and the target RAT and the target RAT support receiving early measurement be appreciated by on of ordinary skill in the art. The processors 1402 are also referred to herein as Processing circuitry. The transceivers 1406 are also referred to herein as radio circuitry. In some ernbodirnents, the functionality of the UE 1400 described above (e.g., one or more fonctions of a network node described herein, e.g., in the “UE Embodiments section) may be fully or partially implemented in software that is, e.g., stored in the memory 1404 and executed by the processor(s) 1402. Note that the UE 1400 may include additional components not illustrated in Figure 14 such as, e.g., one or more user interface components (e.g., an input/output interface including a display, buttons, a touch screen, a microphone, a speaker(s), and/or the îike and/or any other components for allowing input of information into the UE 1400 and/or allowing output of information from the UE 1400), a power supply (e.g., a battery and associated power circuitry), etc.

In some embodiments, a computer program including instructions which, when executed by at least one processor, causes the at least one processor to carry out the functionality of the UE 1400 according to any of the embodiments described herein (e.g., one or more fonctions of a network node described herein, e.g., in the UE Embodiments section) is provided. In some embodiments, a carrier comprising the aforementioned computer program product is provided. The carrier is one of an electronic signal, an optical signai, a radio signal or a computer readable storage medium (e.g., a nontransîtory computer readabie medium such as memory).

Figure 15 is a schematic block diagram of the UE 1400 according to some other embodiments of the présent disclosure, The UE 1400 includes one or more modules 1500, each of which is implemented in software. The module(s) 1500 provide the functionality of the UE 1400 described herein (e.g., one or more fu net ions of s network node described herein, e.g., in the “UE Embodiments” section).

With reference to Figure 16, in accordance with an embodiment, a communication System includes a télécommunication network 1600, such as a 3GPP-type cellular network, which comprises an access network 1602, such as a RAN, and a core network 1604. The access network 1602 comprises a plurality of base stations 1606A, 1606B, 1606C, such as Node Bs, eNBs, gNBs, or other types of wireless Access Points (APs), each defining a corresponding coverage area 1608A, 1608B, 1608C. Each base station 1606A, 1606B, 1606C is connectable to the core network 1604 over a wired or wireless connection 1610. A first UE 1612 located in coverage area 1608C îs configured to wirelessly connect to, or be paged by, the corresponding base station 1606C. A second UE 1614 in coverage area 1608A is wirelessly connectable to the corresponding base station 1606A. While a plurality of UEs 1612, 1614 are illustrated in this example, the connection 1716 termînating at the UE 1714 and the host computer 1702. In providing the service to the user, the client application 1742 may receîve request data from the host application 1712 and provide user data in response to the request data. The OTT connection 1716 may transfer both the request data and the user data, The client application 1742 may internet with the user to generate the user data that it provides.

It is noted that the host computer 1702, the base station 1718, and the UE 1714 illustrated in Figure 17 may be similar or identicaî to the host computer 1616, one of the base stations 1606A, 1606B, 1606C, and one of the UEs 1612, 1614 of Figure 16, respectively. This is to say, the inner workings of these entities may be as shown in Figure 17 and îndependently, the surrounding network topology may be that of Figure 16.

în Figure 17, the OTT connection 1716 has been drawn abstractly to il lu strate the communication between the host computer 1702 and the UE 1714 via the base station 1718 without explicit reference to any intermediary devices and the précisé routing of messages via these devices. The network infrastructure may détermine the routing, which may be configured to hide from the UE 1714 or from the service pro vider operating the host computer 1702, or both. While the OTT connection 1716 is active, the network infrastructure may further take decisions by which il dynamicalîy changes the routing (e.g., on the basis of load balancing considération or reconfiguration of the network).

The wireless connection 1726 between the UE 1714 and the base station 1718 is in accordance with the teachings of the embodiments described throughout this disclosure. One or more of the various embodiments improve the performance of OTT services provided to the UE 1714 using the OTT connection 1716, in which the wireless connection 1726 forms the last segment.

A measurement procedure may be provided for the purpose of monitoring data rate, latency, and other factors on which the one or more embodiments improve. There may further be an optional network functionality for reconfiguring the OTT connection 1716 between the host computer 1702 and the UE 1714, in response to variations in the measurement results. The measurement procedure and/or the network functionality for reconfiguring the OTT connection 1716 may be implemented in the software 1710 and the hardware 1704 of the host computer 1702 or in the software 1740 and the hardware 1734 of the UE 1714, or both. In some embodiments, sensors (not shown) may be deployed in or in association with communication devices through which the OTT connection 1716 passes; the sensors may participate in the measurement procedure by supplying values of ihe monitored quantifies exemplified above, or supplying values of other physical quantifies from which the software 1710, 1740 may compute or estimate the monitored quantifies. The reconfiguring of the OTT connection 1716 may include message format, retransmission settings, preferred routing, etc.; the reconfiguring need not affect the base station 1748, and Ü may be unknown ογ imperceptible to the base station 1718. Sudt procedures and functionalitiês may be known and practiced in the art. in certain embodiments, measurements may involve proprietary UE signaling facilitaîing the host computer 1702 s measurements of throughput, propagation times, latency, and the like. The measurements may be implemented in that the software 1710 and 1740 causes messages to be transmitted, in particular empty or ‘dummy' messages, using the OTT connection 1716 while it monitors propagation times, errors, etc.

Figure 18 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment The communication System includes a host computer, a base station, and a UE which may be those described with reference to Figures 16 and 17. For simplicity of the présent disciosure, oniy drawing référencés to Figure 18 will be included in this section, In step 1800, the host computer provides user data. In sub-step 1802 (wtiich may be optional) of step 1800, the host computer provides the user data by executing a host application in step 1804, the host computer initiâtes a transmission carrying the user data to the UE. !n step 1806 (which may be optional), the base station transmits to the UE the user data which was carried in the transmission that the host computer initiated, in accordance with the teachings of the embodiments described throughout this disclosure. în step 1808 (which may also be optional), the UE executes a client application associated with the host application executed by the host computer.

Figure 19 ts a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment The communication system includes a host computer, a base station, and a UE which may be those described with reference to Figures 16 and 17. For simp^city of the présent disclosure, only drawing référencés to Figure 19 will be included in this section. In step 1900 of the method, the host computer provides user data. In an optional sub-step (not shown) the host computer provides the user data by executing a host application. In step 1902, the host computer initiâtes a transmission carrying the user data to the UE. The transmission may pass via the base station, in accordance with the teachings of the embodiments described throughout this disclosure. In step 1904 (which may be optional), the UE receives the user data carried in the transmission.

Figure 20 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station, and a UE which may be those described with reference to Figures 16 and 17. For simplicity of the présent disclosure, only drawing référencés to

Figure 20 will be included in this section. !n step 2000 (which may be optiona!), the UE receives input data provided by the host computer. Additionaliy or afternatively, in step 2002, the UE provides user data, in sub-step 2004 (which may be optiona!) of step 2000, the UE provides the user data by executing a client application. In sub-step 2006 (which may be optiona!) of step 2002, the UE executes a client application which provides the user data in reaction to the received input data provided by the host computer. In provïding the user data, the executed client application may further consider user input received from the user. Regardless of the spécifie manner in which the user data was provided, the UE initiâtes, in sub-step 2008 (which may be optional), transmission of the user data to the host computer. In step 2010 of the method, the host computer receives the user data transmitted from the UE, in accordance with the teachings of the embodiments described throughout this disclosure.

Figure 21 is a flowehart illustrating a method implemented in a communication System, in accordance with one embodiment. The communication System incîudes a host computer, a base station, and a UE which may be those described with reference to Figures 16 and 17. For simplicity of the présent disclosure, only drawing référencés to Figure 21 will be included in this section. In step 2100 (which may be optional), in accordance with the teachings of the embodiments described throughout this disclosure, the base station receives user data from the UE. !n step 2102 (which may be optional), the base station initiâtes transmission of the received user data to the host computer. In step 2104 (which may be optional), the host computer receives the user data carried in the transmission initiated by the base station.

Any appropriais steps, methods, features, functions, or benefits disclosed herein may be performed through one or more functional units or modules of one or more Virtual apparatuses. Each Virtual apparatus may comprise a number of these functional units. These functional units may be implemented via processing circuitry, which may include one or more microprocessor or microcontroflers, as well as other digital hardware, which may include Digital Signal Processor (DSPs), special-purpose digital logic, and the like. The processing circuitry may be configured to execute program code stored in memory, which may include one or several types of memory such as Read Only Memory (ROM), Random Access Memory (RAM), cache memory, flash memory devices, optical storage devices, etc. Program code stored in memory incîudes program instructions for executing one or more télécommunications and/or data communications protocole as well as instructions for carrying out one or more of the techniques described herein. In some implémentations, the processing circuitry may be used to cause the respective functional unit to perform corresponding functions accordîng one or more embodiments of the présent disclosure.

While processes in the figures may show a particuîar order of operations performed by certain embodiments of the présent disciosure, it should be understood that such order is exemplary (e.g., alternative embodiments may perform the operations in a different order, combine certain operations, overlap certain operations, etc.).

Some example embodiments of the présent disclosure are as foiiows.

Group A Embodiments

Embodiment 1 : A method performed by a wireless device, the method comprising one or more of: receiving (800), from a source RAT network node, one or more measurement configurations for dormant State (e.g., IDLE State, INACTIVE State) early measurements; performing (804), in a first dormant State, early measurements in accordance with at least one of the one or more measurement configurations; performing (808) an inter-RAT œil reselectîon to a target RAT whife in the first dormant State; and, upon performing the inter-RAT cell reselectîon to the target RAT while in the first dormant State, performing (810) one or more actions to handle dormant State measurement configurations and/or dormant State early measurements.

Embodiment 2: The method of embodiment 1 wherein the one or more measurement configurations received from the source RAT network node, comprise:

□ one or more measurement configurations for measuring on cells, frequencies, and/or beams associated with the source RAT;

□ one or more measurêment configurations for measuring on cells, frequencies, and/or beams associated with the target RAT; or □ one or more measurement configurations for measuring on cells, frequencies, and/or beams associated with the source RAT and the target RAT.

Embodiment 3: The method of embodiment 1 or 2 wherein the one or more actions comprise any one or combination of the following actions:

D remaining in the first dormant State in the target RAT;

□ transitioning to a second dormant State in the target RAT;

□ stop performing early measurement accordîng to one or more source RAT measurement configurations, the one or more source RAT measurement configurations being comprised in the one or more measurement configurations for dormant State eariy measurements received from the source RAT network node;

□ start performing early measurements according to one or more target RAT measurement configurations for dormant State early measurements;

□ stop performing early measurements;

□ keep performing early measurements according to the one or more measurement configurations;

O keep a subset of the one or more measurement configurations and keep performing early measurements in accordance with the subset of the one or more measurement configurations;

□ applying one or more measurement configurations for the target RAT on top ofthe one or more measurement configurations and perform early measurements in accordance with the resulting measurement configurations;

□ releasing current eariy measurements performed according to the one or more measurement configurations;

D keeping the current early measurements;

O keeping the current early measurements only if handling of measurement configurations is such that the current measurement configurations are kept;

□ keeping the current early measurements only if handling of measurement configurations is such that the current measurement configurations are kept and an associated timer is not restarted;

G releasing a subset of the early measurements (e.g., those related to the first dormant State but not a second dormant State);

□ releasing a subset of the early measurements that are relevant to the source RAT but not the target RAT ;

□ converting at least some of the early measurements to a format that is suitable for the second RAT.

Embodiment 4: The method of any one of embodiments 1 to 3 wherein at least one of the one or more actions is configured by the source RAT network node.

Embodiment 5: The method of any one of embodiments 1 to 4 further comprising reporting the early measurements to a target RAT network node.

Embodiment 6: The method of any of the previous embodiments, further comprising: providing user data; and forwarding the user data to a host computer via the transmission to the base station.

Group B Embodiments

Embodiment 7: A method performed by a base station in a source RAT, the method comprising: providing (900), to a UE in the source RAT, one or more measurement configurations for dormant State (e.g., IDLE State, INACTIVE State) early measurements; and providing (902), to the UE, information that indicates one or more actions to be performed by the UE upon inter-RAT ceii reselection to a target RAT while in a dormant State.

Embodiment 8: The method of embodiment 7 wherein the one or more measurement configurations provided to the UE comprise:

□ one or more measurement configurations for measuring on cells, frequencies, and/or beams associated with the source RAT;

□ one or more measurement configurations for measuring on cells, frequencies, and/or beams associated with the target RAT; or

D one or more measurement configurations for measuring on cells, frequencies, and/or beams associated with the source RAT and the target RAT.

Embodiment 9: The method of embodiment 7 or 8 wherein the one or more actions comprise any one or combinâtion of the following actions;

□ remaining in a first dormant State in the target RAT;

□ transitioning to a second dormant State in the target RAT;

□ stop performing early measurement according to one or more source RAT measurement configurations, the one or more source RAT measurement configurations being comprised in the one or more measurement configurations for dormant state early measurements received from the source RAT network node;

D start performing early measurements according to one or more target RAT measurement configurations for dormant state early measurements;

G stop performing early measurements;

□ keep performing early measurements according to the one or more measurement configurations;

G keep a subset of the one or more measurement configurations and keep performing early measurements in accordance with the subset of the one or more measurement configurations;

□ applying one or more measurement configurations for the target RAT on top of the one or more measurement configurations and perform early measurements in accordance with the resulting measurement configurations;

□ reieasing current early measurements performed according to the one or more measurement configurations;

□ keeping the current early measurements;

□ keeping the current early measurements only if handiing of measurement configurations is such that the current measurement configurations are kept;

□ keeping the current early measurements only if handiing of measurement configurations is such that the current measurement configurations are kept and an associated timer is not restarted;

□ releasing a subset of the early measurements (e.g., those reiated to the first dormant State but not a second dormant state);

□ releasing a subset of the early measurements that are relevant to the source RAT but not the target RAT ;

□ converting at least some of the early measurements to a format that is suitable for the second RAT

Embodiment 10: A method perfomned by a base station in a target RAT of an inter-RAT cell reselection of a UE, the method comprising: receiving (1000), from the UE, an establishment request or a résumé request after an inter-RAT œil reselection from a source RAT to the target RAT; sending (1002), to the UE, a request for the UE to report early measurements (i.e., dormant state measurements); and receiving (1004), from the UE, one or more early measurements.

Embodiment 11: The method of embodiment 10 wherein the establishment request or résumé request comprises an indication that the UE has early measurements to report.

Embodiment 12: The method of embodiment 10 wherein the establishment request or résumé request comprises a first indication that the UE has early measurements to report for the source RAT and a second indication that the UE has early measurements to report for the target RAT

Embodiment 13; The method of embodiment 10 wherein the request for the UE to report early measurements requests early measurements for the source RAT if the establishment request or résumé request comprises a first indication that the UE has early measurements to report for the source RAT and requests early measurements for the target RAT if the establishment request or résumé request comprises a second indication that the UE has early measurements to report for the source RAT.

Embodiment 14: The method of embodiment 10 wherein the request for the UE to report early measurements requests early measurements for: both the source RAT and the target RAT; only the source RAT; only the target RAT; or only from the RAT from which the UE has indicated that early measurements are available.

Embodiment 15: The method of embodiment 10 further comprising obtaining a UE context of the UE from a source RAT network node, wherein the UE context comprises: information regarding measurement configurations for the UE for the source RAT; information regarding measurement configurations for the UE for the target RAT; or information regarding measurement configurations for the UE for both the source RAT and the second RAT,

Embodiment 16: The method of embodiment 15 wherein the request is based on the UE context of the UE.

Embodiment 17: The method of embodiment 10 wherein sending (1002) the request to the UE comprises sending the request to the UE blindly.

Embodiment 18: The method of embodiment 10 wherein sending (1002) the request to the UE comprises sending the request to the UE based on which RAT types can be configured and signaled in the early measurement report,

Embodiment 19: The method of any of the previous embodiments, further comprising: obtaining user data; and forwardîng the user data to a host computer or a wireless device.

Group C Embodiments

Embodiment 20: A wireless device comprising: processing circuitry configured to perform any of the steps of any of the Group A embodiments: and power supply circuitry configured to supply power to the wireless device.

Embodiment 21: A base station comprising: processing circuitry configured to perform any of the steps of any of the Group B embodiments; and power supply circuitry configured to supply power to the base station.

Embodiment 22: A User Equîprnënt, UE, comprising: an antenna configured to send and receive wireless signais; radio front-end circuitry connected to the antenna and to processing circuitry, and configured to condition signais communicated between the antenna and the processing circuitry; the processing circuitry being configured to perform any of the steps of any of the Group A embodiments; an input interface connected to the processing circuitry and configured to ailow input of information into the UE to be processed by the processing circuitry; an output interface connected to the processing circuitry and configured to output information from the UE that has been processed by the processing circuitry; and a battery connected to the processing circuitry and configured to supply power to the UE.

Embodiment 23: A communication system including a host computer comprising: processing circuitry configured to provide user data; and a communication interface configured to forward the user data to a cellular network for transmission to a User Equipment, UE; wherein the cellular network comprises a base station having a radio interface and Processing circuitry, the base station’s Processing circuitry configured to perform any of the steps of any of the Group B embodiments.

Embodiment 24: The communication System of the previous embodiment further inciuding the base station.

Embodiment 25: The communication System of the previous 2 embodiments, further inciuding the UE, wherein the UE is configured to communicate with the base station.

Embodiment 26: The communication System of the previous 3 embodiments, wherein: the Processing circuitry of the host computer is configured to execute a host application, thereby providing the user data; and the UE comprises processing circuitry configured to execute a client application associated with the host application.

Embodiment 27: A method implemented in a communication System inciuding a host computer, a base station, and a User Equipaient, UE, the method comprising: at the host computer, providing user data; and at the host computer, initiating a transmission carrying the user data to the UE via a cellular network comprising the base station, wherein fine base station performs any of the steps of any of the Group B embodiments.

Embodiment 28: The method of the previous embodiment, further comprising, at the base station, transmitting the user data.

Embodiment 23: The method of the previous 2 embodiments, wherein the user data is provided at the host computer by executing a host application, the method further comprising, at the UE, executing a client application associated with the host application.

Embodiment 30: A User Equipment, UE, configured to communicate with a base station, the UE comprising a radio interface and processing circuitry configured to perform the method of the previous 3 embodiments.

Embodiment 31: A communication System inciuding a host computer comprising: processing circuitry configured to provide user data; and a communication interface configured to forward user data to a cellular network for transmission to a User Equipment, UE; wherein the UE comprises a radio interface and processing circuitry, the UE’s components configured to perform any of the steps of any of the Group A embodiments.

Embodiment 32: The communication System of the previous embodiment, wherein the cellular network further includes a base station configured to communicate with the UE.

Embodiment 33: The communication System of the previous 2 embodiments, wherein: the processing circuitry of the host computer is configured to execute a host application, thereby providing the user data; and the UE’s processing circuitry is configured to execute a client application associated with the host application.

Embodiment 34: A rnethod impfemenîed in a communication System including a host computer, a base station, and a User Equipment, UE, the method comprising: at the host computer, providing user data; and at the host computer, initiating a transmission carrying the user data to the UE via a cellular network comprising the base station, wherein the UE performs any of the steps of any of the Group A embodiments.

Embodiment 35: The method of the previous embodiment, further comprising at the UE, receiving the user data from the base station.

Embodiment 36: A communication system including a host computer comprising: communication interface configured to receive user data originating from a transmission from a User Equipment, UE, to a base station; wherein the UE comprises a radio interface and processing circuitry, the UE’s processing circuitry configured to perform any of the steps of any of the Group A embodiments.

Embodiment 37: The communication system of the previous embodiment, further including the UE.

Embodiment 38: The communication system of the previous 2 embodiments, further including the base station, wherein the base station comprises a radio interface configured to communicate with the UE and a communication interface configured to forward to the host computer the user data carried by a transmission from the UE to the base station.

Embodiment 39: The communication System of the previous 3 embodiments, wherein: The processing circuitry of the host computer is configured to execute a host application; and the UE’s processing circuitry is configured to execute a client application associated with the host application, thereby providing the user data.

Embodiment 40: The communication system of the previous 4 embodiments, wherein: The processing circuitry of the host computer is configured to execute a host application, thereby providing request data; and the UE’s processing circuitry is configured to execute a client application associated with the host application, thereby providing the user data in response to the request data.

Embodiment 41: T method implemented in a communication system including a host computer, a base station, and a User Equipment, UE, the method comprising: at the host computer, receiving user data transmitted to the base station from the UE, wherein the UE performs any of the steps of any of the Group A embodiments.

Embodiment 42: The method of the previous embodiment, further comprising, at the UE, providing the user data to the base station.

Embodiment 43: The method of the previous 2 embodiments, further comprising: at the UE, executing a client application, thereby providing the user data to be transmitted; and at the host computer, executing a host application associated with the client application.

Embodiment 44: The method of the previous 3 embodiments, further comprising: at the UE, executing a client application; and at the UE, receiving input data to the client application, the input data being provided at the host computer by executing a host application associated with the client application; wherein the user data to be transmitted is provided by the client application in response to the input data.

Embodiment 45: A communication System including a host computer comprising a communication interface configured to receive user data originating from a transmission from a User Equîpment, UE, to a base station, wherein the base station comprises a radio interface and processing circuitry, the base station’s processing circuitry configured to perform any of the steps of any of the Group B embodiments.

Embodiment 46: The communication System of the previous embodiment further including the base station.

Embodiment 47: The communication System of the previous 2 embodiments, further including the UE, wherein the UE is configured to communicate with the base station,

Embodiment 48: The communication System of the previous 3 embodiments, wherein; the processing circuitry of the host computer is configured to execute a host application; and the UE is configured to execute a client application associated with the host application, thereby providing the user data to be received by the host computer.

Embodiment 49: A method implemented in a communication System including a host computer, a base station, and a User Equîpment, UE, the method comprising: at the host computer, receiving, from the base station, user data originating from a transmission which the base station has received from the UE, wherein the UE performs any of the steps of any of the Group A embodiments.

Embodiment 50: The method of the previous embodiment, further comprising at the base station, receiving the user data from the UE.

Embodiment 51: The method of the previous 2 embodiments, further comprising at the base station, initiating a transmission of the received user data to the host computer.

At least some of the following abbreviations may be used in this disclosure. If there is an inconsistency between abbreviations, preference should be given to how it is

used above.	!f listed multiple times below, the first listing should be preferred over any
	subséquent listing(s). • 3GPP	Third Génération Partnership Project
	•	5G	Fifth Génération
5	•	5GC	Fifth Génération Core
	•	5GS	Fifth Génération System
	«	AMF	Access and Mobility Management Function
	•	AP	Access Point
	£	AS	Access Stratum
10	•	ASIC	Application Spécifie Integrated Circuit
	B	AUSF	Authentication Server Function
	•	CA	Carrier Aggregation
	•	CE	Control Elément
	•	CN	Core Network.
15	•	CPU	Central Processing Unit
	•	DC	Dual Connectivity
	•	DRX	Discontinuous Réception
	•	DSP	Digital Signal Processor
	•	eNB	Enhanced or Evolved Node B
20	B	EN-DC	Evolved Universal Terre striai Radio Access Network New
	*	eLTE	Radio Dual Connectivity Enhanced Long Term Evolution
	B	EPC	Evolved Packet Core
	B	E-UTRA	Evolved Universal Terrestrial Radio Access
25	•	E-UTRAN	Evolved Universal Terrestrial Radio Access Network
	•	FPGA	Fieid Programmable Gâte Array
	B	gNB	New Radio Base Station
	V	HSS	Home Subscnber Server
	B	ID	Identity
30	*	1-RNTI	Inactive Radio Network Temporary identifier
	B	LTE	Long Term Evolution
	B	MAC-	Medium Access Control
	B	MCG	Master Cell Group
	♦	MeNB	Master Enhanced or Evolved Node B
35	B	MME	Mobility Management Entity

•	MR-DC	Multi-Radio Dual Connectivity
•	ms	Millisecond
•	MTC	Machine Type Communication
•	NE	New Radio Evolved Universal Terrestrial Radio Access
5	NEF	Network Exposure Function
•	NGEN-DC	Next Génération Dual Connectivity
•	NG-RAN	Next Génération Radio Access Network
•	NR	New Radio
	NRF	Network Repository Function
10	NSSF	Network Slice Sélection Function
	OTT	Over-the-Top
•	PCeii	Primary Cell
•	PCF	Policy Contrai Function
«	PCI	Physical Cell identity
15	P-GW	Packet Data Network Gateway
•	PSCell	Primary Secondary Cell
•	RAM	Random Access Memory
•	RAN	Radio Access Network
•	RAT	Radio Access Technology
20	ROM	Read Only Memory
•	RRC	Radio Resource Contra!
•	RRH	Remote Radio Head
*	RRM	Radio Resource Management
•	RSRP	Référencé Signal Received Power
25	RSRQ	Référencé Signal Received Quality
♦	SA	Stand-Aione
•	SCEF	Service Capability Exposure Function
•	SCell	Secondary Cell
»	SCG	Secondary Cell Group
30	SI B	System Information Block
•	SMF	Session Management Function
β	SpCeü	Spécial Cell
•	S-TMSI	System Architecture Evolution Temporary Mobile Subscriber Identity
35	TS	Technical Spécification

	58
• UDM	Unified Data Management
• UE	User Equipment
• UPF	User Plane Function
• W1D	Work item Description
5 Those skilled	in the art witï recognize improvements and modifications to the

embodiments of the présent disclosure. Ail such improvements and modifications are considered within the scope of the concepts disclosed herein.

Claims (14)

1. A method performed by a wireless device (712), the method comprising:

receiving (800) one or more dormant state measurement configurations from a network node of a source Radio Access Technology, RAT;

performing (804) measurements while in a first dormant state in accordance with at least one of the one or more dormant state measurement configurations;

performing (808) an inter-RAT cell reselection from the source RAT to a target RAT while in the first dormant state;

upon performing the inter-RAT cell reselection from the source RAT to the target RAT while in the first dormant state, performing (810) one or more actions to handle dormant state measurement configurations, to handle measurements performed in accordance with dormant state measurement configurations, or to handle both dormant state measurement configurations and measurements performed in accordance with dormant State measurement configurations, wherein the one or more dormant state measurement configurations comprise one or more dormant state measurement configurations for the source RAT of the wireless device (712), and the one or more actions comprise stopping performance of measurements made in accordance with the one or more dormant state measurement configurations for the source RAT;

reporting (812) the measurements to a target RAT network node; and wherein the one or more dormant state measurement configurations received from the network node comprise one or more dormant state measurement configurations for measuring on cells, frequencies, and/or beams associated with the source RAT.

2. The method of claim 1 wherein stopping performance of measurements made in accordance with the one or more dormant State measurement configurations for the source RAT comprises stopping a timer that limits an amount of time that the wireless device is to perform measurements in accordance with the one or more dormant state measurement configurations for the source RAT.

3. The method of claim 1 or 2 wherein stopping performance of measurements made in accordance with the one or more dormant State measurement configurations for the source RAT comprises releasing the one or more dormant state measurement configurations for the source RAT.

4. The method of any of daims 1 to 3 wherein the one or more actions further comprise transitioning to a second dormant State in the target RAT.

5. The method of daim 1 wherein the one or more actions comprise stopping performance of measurements made while in a dormant state.

6. The method of any one of daims 1 to 5 wherein at least one of the one or more actions is configured by the network node.

7. The method of daim 1 wherein the one or more dormant State measurement configurations received from the network node comprise one or more dormant State measurement configurations for measuring on cells, frequencies, and/or beams associated with the target RAT.

8. The method of any one of daims 1 to 7 further comprising reporting (812) the measurements to a target RAT network node.

9. A wireless device (712) adapted to:

receive (800) one or more dormant State measurement configurations from a network node of a source Radio Access Technology, RAT;

perform (804) measurements while in a first dormant State in accordance with at least one ofthe one or more dormant state measurement configurations;

perform (808) an inter-RAT cell reselection from the source RAT to a target RAT while in the first dormant state;

upon performing the inter-RAT cell reselection from the source RAT to the target RAT while in the first dormant state, perform (810) one or more actions to handle dormant State measurement configurations, to handle measurements performed in accordance with dormant state measurement configurations, or to handle both dormant state measurement configurations and measurements performed in accordance with dormant state measurement configurations, wherein the one or more dormant state measurement configurations comprise one or more dormant state measurement configurations for the source RAT of the wireless device (712), and the one or more actions comprise stopping performance of measurements made in accordance with the one or more dormant state measurement configurations for the source RAT;

reporting (812) the measurements to a target RAT network node; and wherein the one or more dormant State measurement configurations recetved from the network node comprise one or more dormant State measurement configurations for measuring on cells, frequencies, and/or beams associated with the source RAT

10. The wireless device (712) of claim 9 wherein the wireless device (712) is further adapted to perform the method of any of claims 2 to 8.

11. A method performed by a base station (702) using a source Radio Access Technology, RAT, the method comprising:

providing (900), to a wireless device (712) using the source RAT, one or more dormant state measurement configurations; and providing (902), to the wireless device (712), information that indicates one or more actions to be performed by the wireless device (712) upon inter-RAT cell reselection from the source RAT to a target RAT while in a dormant state in order to handle measurements performed in accordance with dormant state measurement configurations, or to handle both dormant state measurement configurations and measurements performed in accordance with dormant state measurement configurations, wherein the one or more actions comprise: stop performing measurement according to one or more source RAT measurement configurations, the one or more source RAT measurement configurations being comprised in the one or more dormant state measurement configurations, and wherein the one or more dormant state measurement configurations provided to the wireless device (712) comprise:

□ one or more dormant state measurement configurations for measuring on cells, frequencies, and/or beams associated with the source RAT;

□ one or more dormant state measurement configurations for measuring on cells, frequencies, and/or beams associated with the target RAT; or □ one or more dormant state measurement configurations for measuring on cells, frequencies, and/or beams associated with the source RAT and the target RAT.

12. The method of claim 11 wherein the one or more actions comprise any one or combination of the following actions:

• transitioning to a second dormant state in the target RAT;

• releasing current measurements performed according to the one or more dormant State measurement configurations.

13. A base station (702) adapted to:

provide (900) one or more dormant state measurement configurations to a wireless device (712) using source Radio Access Technology, RAT; and provide (902), to the wireless device (712), information that indicates one or more actions to be performed by the wireless device (712) upon inter-RAT cell reselection from the source RAT to a target RAT while in a dormant state in orderto handle measurements performed in accordance with dormant state measurement configurations, or to handle both dormant state measurement configurations and measurements performed in accordance with dormant state measurement configurations, wherein the one or more actions comprise: stop performing measurement according to one or more source RAT measurement configurations, the one or more source RAT measurement configurations being comprised in the one or more dormant state measurement configurations, and wherein the one or more dormant state measurement configurations provided to the wireless device (712) comprise:

□ one or more dormant state measurement configurations for measuring on cells, frequencies, and/or beams associated with the source RAT;

□ one or more dormant state measurement configurations for measuring on cells, frequencies, and/or beams associated with the target RAT; or □ one or more dormant state measurement configurations for measuring on cells, frequencies, and/or beams associated with the source RAT and the target RAT.

14. The base station (702) of claim 13 wherein the base station (702) is further adapted to perform the method of claim 12.