WO2023068992A1

WO2023068992A1 - Relaxed measurement procedure for multicarrier operation in rrc connected

Info

Publication number: WO2023068992A1
Application number: PCT/SE2022/050947
Authority: WO
Inventors: Mattias BERGSTRÖM; Muhammad Ali Kazmi; Santhan THANGARASA; Stefan WÄNSTEDT
Original assignee: Telefonaktiebolaget Lm Ericsson (Publ)
Priority date: 2021-10-21
Filing date: 2022-10-19
Publication date: 2023-04-27
Also published as: EP4420393A1

Abstract

Systems and methods for relaxed measurement procedure for multicarrier operation in Radio Resource Control (RRC) connected status of a User Equipment (UE) are disclosed herein. In some embodiments, a method performed by the UE in a multicarrier system with a network node comprises evaluating, based on one or more rules, whether one or more relaxed measurement criteria are met on one or more cells in a Group of Cells (GOCs) and sending a report to the network node. The report comprises a result of evaluating, based on the one or more rules, whether the one or more relaxed measurement criteria are met on the one or more cells in the GOCs.

Description

RELAXED MEASUREMENT PROCEDURE FOR MULTICARRIER OPERATION IN RRC CONNECTED

Related Applications

This application claims the benefit of provisional patent application serial number 63/270,366, filed October 21, 2021, the disclosure of which is hereby incorporated herein by reference in its entirety.

Technical Field

The present disclosure is direct to relaxed measurement procedure for multicarrier operation in Radio Resource Control (RRC) connected status of a User Equipment (UE), in particular, a New Radio (NR) UE.

Background

1.1 Reduced Capability (RedCap) New Radio (NR) Devices

Fifth Generation (5G) is the fifth generation of cellular technology and was introduced in Release 15 of the Third Generation Partnership Project (3GPP) standard. It is designed to increase speed, reduce latency, and improve flexibility of wireless services. The 5G system (5GS) includes both a Next Generation Radio Access Network (NG-RAN) which makes use of a new air interface called NR, and a new Core Network which is referred to as the 5G Core (5GC).

The initial release of 5G in Release 15 is optimized for Mobile BroadBand (MBB) and Ultra-Reliable and Low Latency Communication (URLLC). These services require very high data rates and/or low latency and therefore puts high requirements on the User Equipment (UE). To enable 5G to be used for other services with more relaxed performance requirements, a new low complexity UE type is introduced in Release 17, which is referred to as a Reduced Capability (RedCap) UE. The new low complexity UE type is particularly suited for Machine Type Communication (MTC) services such as wireless sensors or video surveillance, but the new low complexity UE type may also be used for MBB services with lower performance requirements such as wearables. The low complexity UE has reduced capabilities, compared to a Release 15 NR UE, such as a possibility to support lower bandwidth compared to what is currently required for a NR UE and a possibility to support only one reception (Rx) branch and one Multiple-Input Multiple-Output (MIMO) layer. Detailed features of RedCap UEs re described in RP-201918 (titled "Support of reduced capability NR devices") from 3GPP Technical Specification Group (TSG) Radio Access Network (RAN) Meeting #91e (March 2021).

1.2 Radio Resource Management (RRM) Measurement Relaxation

When an NR device is in Radio Resource Control (RRC) connected mode, it may be configured to perform RRM measurements. RRM measurements are, for example, measurements of signal strength at the UE. The UE may be configured to report the RRM measurements of the UE to the network.

The RRM measurements consume the UE's power due to the need to use the receiver and also the transmitter for reporting of those measurements. Hence, it is discussed in 3GPP to introduce relaxed RRM measurements in RRC connected mode. The measurements would be relaxed in the sense that the requirements for the RRM measurements are not as stringent as they normally are, e.g., by decreasing the frequency on how often the UE needs to perform the RRM measurements.

Relaxed RRM measurements may save some UE energy. However, they may at the same time reduce the accuracy of the measurements or some measurements may never be performed or sent to the network. Hence, the relaxed RRM measurements shall only be performed when certain conditions are met.

It has been discussed that the UE shall monitor those certain conditions and report to the network when they are fulfilled and not. One possible condition is that the UE-measured Reference Signal Received Power (RSRP) is above a certain threshold. In response to a report about the UE's measurement about RSRP, the network may configure the UE to perform RRM relaxation. Two approaches are discussed in current standardization activities. First, the network explicitly indicates that the UE shall apply a relaxed RRM measurement behavior, which would likely be specified in a specification, e.g., that the frequency of the measurements is reduced. Second, the network reconfigures the RRM measurement configuration for the UE. For example, the network may configure the UE not to perform measurements on some frequencies or to increase the periodicity of RRM measurement reporting.

1.3 Relaxed Measurements The relaxed monitoring criteria for a neighbor cell are specified in 3GPP Technical Specification (TS) 38.304 V16.4.0. In RRC idle and RRC inactive states, the UE may be configured to relax neighbor cell measurements (e.g., for cell reselection) when the UE meets one or more relaxed measurement criteria. The UE may be configured for applying relaxed measurements via higher layer signaling e.g., in a System Information Block (SIB) such as SIB2. Examples of criteria are UE in low mobility, UE not-at-cell-edge, and combined criterion or combination of two or more criteria (e.g., when both of the conditions (UE in low mobility AND UE not-at-cell-edge criteria) are met).

1.3.1 Relaxed Measurement Criterion for UE with Low Mobility

In one embodiment, the relaxed measurement criterion for a UE with low mobility is fulfilled when the UE speed is below a certain threshold. The UE speed may be expressed in terms of distance per unit time (e.g., Y1 kilometer (km)/hour) and/or in Doppler frequency (e.g., Y2 Hertz). In one embodiment, the relaxed measurement criterion for a UE with low mobility is fulfilled if the UE is stationary, static, or does not move.

In another embodiment, the low mobility criterion is met when the received signal level at the UE with respect to the cell is static or quasi-static over a certain time period (T_s). The received signal at the UE with respect to the cell is static or quasi- static if the received signal at the UE does not change by more than a certain margin over a certain time period, e.g., the variance of the measured signal levels is within a certain threshold. Examples of the received signal are signal strength, path loss, RSRP, Ll-RSRP, Ll-Signal-to-Interference-plus-Noise Ratio (SINR).

In one embodiment, the relaxed measurement criterion for a UE with low mobility based on signal variation is fulfilled when the following condition is met for a cell (e.g., for the serving cell of the UE):

(SrxievRef ^— Srxlev) < SsearchDeltaP, where:

• Srxiev = current Srxiev value of the serving cell (dB),

• SrxievRef = reference Srxiev value of the serving cell (dB), set as follows: o after selecting or reselecting a new cell or if (Srxiev - Sr_XievRef) > 0 or if the relaxed measurement criterion has not been met for a duration of TsearchDeitaP, then the UE sets the value of SrxievRef to the current Srxlev value of the serving cell.

Srxiev is further defined as follows:

Srxlev ⁼ Qrxlevmeas ^— (Qrxievmin + Qrxlevminoffset) ^— Pcompensation ^— Qoffsetemp. where

• Srxiev is the cell selection received (RX) level value (dB),

• Qrxlevmeas is the measured cell RX level value (RSRP),

• Qrxievmin (signaled by the cell) is the minimum required RX level in the cell (dBm),

• Qrxlevminoffset (signaled by the cell) is the offset to the signaled Qrxievmin, and

• Qoffsettemp (signaled by the cell) is the offset temporarily applied to a cell.

1.3.2 Relaxed Measurement Criterion for UE Not at Cell Edge

In one embodiment, the relaxed measurement criterion for UE not at cell edge is fulfilled when the received signal level at the UE with respect to a cell is above threshold, e.g., signal strength is above signal strength threshold and/or signal quality is above signal quality threshold.

In another embodiment, the relaxed measurement criterion for UE not at cell edge is fulfilled when the following condition is met for a cell (e.g., for the serving cell of the UE):

Srxlev > SsearchThreshoIdP/ and

Squai > SsearchThresholdQ/ if SsearchThresholdQ iS Configured, where

• Srxiev = current Srxiev value of the serving cell (dB), and

• Squai = current S_quai value of the serving cell (dB).

Squai is further defined as follows:

Squai ⁼ Qqualmeas ^— (Qqualmin + Qqualminoffset) " Qoffsetemp where

• Squai is the cell selection quality value (dB),

• Qquaimeas is the measured cell quality level value (RSRQ),

• Qquaimin (signaled by the cell) is the minimum required quality level in the cell (dB), and

• Qqualminoffset (signaled by the cell) is the offset to the signaled Qquaimin. 1.4 Multi-Carrier System

In a multi-carrier system, the UE may operate using multiple carriers (sometimes referred to as cells) that the network has available. With a greater number of carriers, more spectrum may be used by the UE and hence higher throughput may be achieved. Examples of operations in the multi-carrier system are Carrier Aggregation (CA), Dual Connectivity (DC), and Multi-Connectivity (MuC). A carrier frequency in the multi-carrier system is also called as a Component Carrier (CC), a frequency layer, a serving carrier, a frequency channel, etc.

A UE may be configured with a subset of the cells offered by the network and the number of aggregated cells configured for one UE may change dynamically through time based on, for example, a terminal traffic demand, a type of service used by the terminal, and a system load. A cell that a terminal or a UE is configured to use is referred to as a "serving cell" for that terminal or the UE. Examples of serving cells are a Special Cell (SpCell) and a Secondary Cell (SCell). Examples of SpCell are a Primary Cell (PCell) and a Primary Secondary Cell (PSCell). The carrier frequencies of the SpCell, the SCell, the PCell, and the PSCell are referred to as a Special CC (SpCC) or simply a SpC, a Secondary CC (SCC), a Primary CC (PCC), and a Primary Secondary CC (PSCC) or simply a PSC, respectively.

In CA, the UE has one Primary Cell (PCell) and zero or more Secondary Cells (SCells). The term "serving cell" includes both the PCell and the SCells. A UE's PCell is UE-specific. The PCell is considered more important and, for example, some control signaling is handled via the PCell.

DC includes a Master Cell Group (MCG) that contains at least a PCell and a Secondary Cell Group (SCG). Each of the MCG and the SCG may further contain one or more SCells. The PCell manages (e.g., configures, changes, or releases) all SCells in an MCG and a PSCell in a SCG. The PSCell manages all SCells in the SCG. The cells in the MCG and the SCG may belong to the same Radio Access Technology (RAT) (e.g., all cells are NR in both the MCG and the SCG, like in NR DC (NR-DC)) or they may belong to different RATs (e.g., Long Term Evolution (LTE) cells in a MCG and NR cells in a SCG, like in Evolved Universal Terrestrial Access (E-UTRA)/NR DC (EN-DC); or NR cells in a MCG and LTE cells in a SCG like in NR/E-UTRA DC (NE-DC)).

In addition, the concept of "configuration" of cells or the concept of "activation" has been introduced for SCells (not for the PCell). Cells may be configured (or reconfigured) using RRC signaling, which may be slow, and the SCells may be activated (or deactivated) using a Medium Access Control (MAC) Control Element (CE), which is faster. Since the activation process is based on MAC CEs, an activation/de-activation process may quickly adjust the number of activated cells to match the number of activated cells that are required to fulfill data rate needed at any given time. Activation therefore provides the possibility to keep multiple cells configured for activation on an as-needed basis.

An SCell may be activated/de-activated via: (a) SCell Activation/Deactivation MAC CE, (b) sCellDeactivationTimer timer, or (c) RRC (re-)configuration (sCellState). The sCellDeactivationTimer is a timer which, upon expiry triggers the UE to deactivate the SCell. There is one such timer per SCell. The timer is started/restarted when the UE is using the cell, e.g., when the UE is scheduled on the SCell.

Summary

Systems and methods for relaxed measurement procedure for multicarrier operation in Radio Resource Control (RRC) connected status of a User Equipment (UE) (in particular, a New Radio (NR) UE) are disclosed herein. In one embodiment, a method performed by a UE configured for multi-carrier operation in a cellular communications system comprises evaluating, based on one or more rules, whether one or more relaxed measurement criteria are met on one or more cells in a Group of Cells (GOCs) configured for the UE for multi-carrier operation and sending a report to the network node, the report comprising a result of evaluating, based on the one or more rules, whether the one or more relaxed measurement criteria are met on the one or more cells in the GOCs. In this manner, the UE's power consumption and signaling overheads may be reduced.

In one embodiment, the multi-carrier operation is one of Carrier Aggregation (CA), Dual Connectivity (DC), or Multi-Connectivity (MC).

In one embodiment, the GOCs is a Master Cell Group (MCG) or a Secondary Cell Group (SCG).

In one embodiment, the GOCs comprises a Primary Cell (PCell), and one or more Secondary Cells (SCells). In one embodiment, the one or more cells in the GOCs evaluated based on the one or more rules comprise: (a) the PCell, (b) at least one of the one or more SCells, or (c) both the PCell and at least one of the one or more SCells.

In one embodiment, the GOCs comprises a Primary Secondary Cell (PSCell), and one or more SCells. In one embodiment, the one or more cells in the GOCs evaluated based on the one or more rules comprise: (a) the PSCell, (b) at least one of the one or more SCells, or (c) both the PSCell and at least one of the one or more SCells.

In one embodiment, the one or more cells in the GOCs evaluated based on the one or more rules consist of all cells in the GOCs.

In one embodiment, the one or more cells in the GOCs evaluated based on the one or more rules consist of a subset of the one or more cells in the GOCs. In one embodiment, the subset of the one or more cells in the GOCs is predefined or configured. In another embodiment, the subset of the one or more cells in the GOCs dynamically changes over time as configurations of the UE for multi-carrier operation change. In one embodiment, the subset of the one or more cells in the GOCs evaluated based on the one or more rules consist of a single cell. In another embodiment, the subset of the one or more cells in the GOCs evaluated based on the one or more rules consist of all cells in a same MCG or all cells in a same SCG.

In one embodiment, the one or more relaxed measurement criteria are met when signal quality of the UE is above a signal quality threshold.

In one embodiment, the one or more relaxed measurement criteria are criteria that must be met in order for the UE to perform relaxed measurements when in connected stated and configured for multi-carrier operation. In one embodiment, the relaxed measurements are relaxed Radio Resource Management (RRM) measurements. In one embodiment, the relaxed measurements have one or more relaxed requirements comprising a relaxed measurement time, a relaxed measurement accuracy, or a relaxed measurement reporting periodicity. In another embodiment, the relaxed measurements have one or more relaxed requirements comprising a relaxed evaluation period. In another embodiment, the relaxed measurements have one or more relaxed requirements comprising a relaxed measurement time which is a function of a normal measurement time and a scaling factor.

In one embodiment, one or more parameters related to the one or more rules are received from the network node.

In one embodiment, the one or more rules are pre-defined.

In one embodiment, the one or more relaxed measurement criteria relate to mobility of the UE. In one embodiment, evaluating, based on the one or more rules, whether the one or more relaxed measurement criteria are met on the one or more cells in the GOCs comprises evaluating whether the mobility of the UE is below a threshold on the one or more cells in the GOCs. In one embodiment, the one or more relaxed measurement criteria relate to the UE located not at an edge of the cell. In one embodiment, evaluating, based on the one or more rules, whether the one or more relaxed measurement criteria are met on the one or more cells in the GOCs comprises evaluating whether a signal strength of the UE is above a threshold on the one or more cells in the GOCs.

In one embodiment, the method further comprises receiving, from the network node, a message to perform the evaluating the one or more relaxed measurement criteria, wherein the report is sent to the network node within a time period from a reference time. In one embodiment, the reference time is the time when the UE receives, from the network node, the message to perform the evaluating the one or more relaxed measurement criteria. In another embodiment, the reference time is the time which occurs at a future time after the UE receives, from the network node, the message to perform the evaluating the one or more relaxed measurement criteria.

In one embodiment, the report comprises at least one of (a) the UE's indication for which cells the relaxed measurement criteria are fulfilled, (b) information about cells in the GOCs which meet the relaxed measurement criteria but do not belong to a subset of the GOCs, and (c) information about the relaxed measurement criteria that are not met for certain cells.

In one embodiment, the UE sends the report to the network node via a signaling message, which correspond to at least one of (a) layer 1 message, (b) a Physical Random Access Channel (PRACH) message, (c) a Medium Access Control (MAC) message, and (d) a Radio Resource Control (RRC) message.

Corresponding embodiments of a UE are also disclosed. In one embodiment, a UE in a multi-carrier system with a network node is adapted to evaluate, based on one or more rules, whether one or more relaxed measurement criteria are met on one or more cells in a GOCs and send a report to the network node, the report comprising a result of evaluating, based on the one or more rules, whether the one or more relaxed measurement criteria are met on the one or more cells in the GOCs.

In another embodiment, a UE for a multi-carrier system with a network node 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 UE to evaluate, based on one or more rules, whether one or more relaxed measurement criteria are met on one or more cells in a GOCs and send a report to the network node, the report comprising a result of evaluating, based on the one or more rules, whether the one or more relaxed measurement criteria are met on the one or more cells in the GOCs.

Embodiments of a method performed by a network node in a multi-carrier system with a UE are also disclosed. In one embodiment, a method performed by a network node in a multi-carrier system with a UE comprises configuring one or more parameters related to one or more rules to the UE and receiving a report from the UE, the report comprising a result of an evaluation at the UE, based on the one or more rules, whether one or more relaxed measurement criteria are met on one or more cells in a GOCs.

In one embodiment, the method further comprises performing one or more operational tasks in response to the report received from the UE.

In one embodiment, the method further comprises sending, to the UE, a message instructing the UE to evaluate, based on the one or more rules, whether the one or more relaxed measurement criteria are met on the one or more cells in the GOCs.

In one embodiment, the one or more operational tasks comprise at least one of

(a) configuring the UE such that the UE is allowed to perform a relaxed measurement;

(b) reconfiguring a relaxation factor to allow relaxation of one or more measurement requirements at the UE; and (c) adapting one or more measurement configuration parameters for the UE.

In one embodiment, the one or more operational tasks comprise, for a cell where the relaxed measurement criteria are not fulfilled, at least one of (a) disabling relaxed measurement for the cell at the UE; (b) reconfiguring an existing relaxation factor for relaxed measurements for the cell at the UE; and (c) configuring more resources.

Corresponding embodiments of a network node are also disclosed. In one embodiment, a network node for a multi-carrier system with a UE is adapted to configure one or more parameters related to one or more rules to the UE and receive a report from the UE, the report comprising a result of an evaluation at the UE, based on the one or more rules, whether one or more relaxed measurement criteria are met on one or more cells in a GOCs.

In another embodiment, a network node for a multi-carrier system with a UE comprises processing circuitry configured to cause the network node to configure one or more parameters related to one or more rules to the UE and receive a report from the UE, the report comprising a result of an evaluation at the UE, based on the one or more rules, whether one or more relaxed measurement criteria are met on one or more cells in a GOCs.

Brief of the

The accompanying drawing figures incorporated in and forming a part of this specification illustrate several aspects of the disclosure, and together with the description serve to explain the principles of the disclosure.

Figure 1 illustrates one example of a cellular communications system in which embodiments of the present disclosure may be implemented.

Figure 2 illustrates an example embodiment of the present disclosure.

Figure 3 illustrates a schematic block diagram of a radio access node according to some embodiments of the present disclosure.

Figure 4 illustrates a schematic block diagram that illustrates a virtualized embodiment of the radio access node according to some embodiments of the present disclosure.

Figure 5 illustrates a schematic block diagram of the radio access node according to some other embodiments of the present disclosure.

Figure 6 illustrates a schematic block diagram of a wireless communication device according to some embodiments of the present disclosure.

Figure 7 illustrates a schematic block diagram of the wireless communication device according to some other embodiments of the present disclosure.

Detailed

The embodiments set forth below represent information to enable those skilled in the art to practice the embodiments and illustrate the best mode of practicing the embodiments. Upon reading the following description in light of the accompanying drawing figures, those skilled in the art will understand the 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 communication device.

Radio Access Node: As used herein, a "radio access node" or "radio network node" or "radio access network node" is any node in a Radio Access Network (RAN) of a cellular communications network that operates to wirelessly transmit and/or receive signals. 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 Generation Partnership Project (3GPP) Fifth Generation (5G) NR network or an enhanced or evolved Node B (eNB) in a 3GPP Long Term Evolution (LTE) network), a high-power or macro base station, a low-power base station (e.g., a micro base station, a pico base station, a home eNB, or the like), a relay node, a network node that implements part of the functionality of a base station (e.g., a network node that implements a gNB Central Unit (gNB-CU) or a network node that implements a gNB Distributed Unit (gNB-DU)) or a network node that implements part of the functionality of some other type of radio access node.

Core Network Node: As used herein, a "core network node" is any type of node in a core network or any node that implements a core network function. Some examples of a core network node include, e.g., a Mobility Management Entity (MME), a Packet Data Network Gateway (P-GW), a Service Capability Exposure Function (SCEF), a Home Subscriber Server (HSS), or the 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 Selection Function (NSSF), a Network Exposure Function (NEF), a Network Function (NF) Repository Function (NRF), a Policy Control Function (PCF), a Unified Data Management (UDM), or the like.

Communication Device: As used herein, a "communication device" is any type of device that has access to an access network. Some examples of a communication device include, but are not limited to: mobile phone, smart phone, sensor device, meter, vehicle, household appliance, medical appliance, media player, camera, or any type of consumer electronic, for instance, but not limited to, a television, radio, lighting arrangement, tablet computer, laptop, or Personal Computer (PC). The communication device may be a portable, hand-held, computer-comprised, or vehiclemounted mobile device, enabled to communicate voice and/or data via a wireless or wireline connection.

Wireless Communication Device: One type of communication device is a wireless communication device, which may be any type of wireless device that has access to (i.e., is served by) a wireless network (e.g., a cellular network). Some examples of a wireless communication device include, but are not limited to: a User Equipment device (UE) in a 3GPP network, a Machine Type Communication (MTC) device, and an Internet of Things (loT) device. Such wireless communication devices may be, or may be integrated into, a mobile phone, smart phone, sensor device, meter, vehicle, household appliance, medical appliance, media player, camera, or any type of consumer electronic, for instance, but not limited to, a television, radio, lighting arrangement, tablet computer, laptop, or PC. The wireless communication device may be a portable, hand-held, computer-comprised, or vehicle-mounted mobile device, enabled to communicate voice and/or data via a wireless connection.

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 terminology or terminology 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, reference may be made to the term "cell"; however, particularly 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 equally applicable to both cells and beams.

There currently exist certain challenge(s). In Radio Resource Control (RRC) connected state, a UE may be configured in multi-carrier operation e.g., with two or more serving cells. The UE may be configured with relaxed measurement in RRC connected state to save the UE's power. There is no procedure for allowing relaxed measurement in RRC connected state when the UE is configured in multi-carrier operation. If the UE applies the legacy relaxed measurement procedure, then, in some scenarios, the UE may not enter in the relaxed measurement mode where, in fact, it might be possible to operate in the relaxed measurement mode. Therefore, the UE may not be able to save its power or may not achieve sufficient power saving. In multicarrier operation, in some scenarios, the UE may also be configured with very large number of cells, e.g., in Frequency Range 2 (FR2). Therefore, new procedures are needed for allowing the UE to evaluate and report when a relaxed measurement criterion is met in RRC connected state.

Certain aspects of the present disclosure and their embodiments may provide solutions to the aforementioned or other challenges. Embodiments of the solutions described herein are related to a scenario in which the UE is configured for multi-carrier operation with at least two serving cells (e.g., Special Cell (SpCell) and Secondary Cell (SCell); two SpCells). In some embodiments, the UE is configured (e.g., based on pre-defined rule and/or configured by the network) to evaluate whether it meets one or more relaxed measurement criteria on all cells in a group of cells (GOCs). The UE further obtains one or more relaxed measurement criteria based on a rule which may be pre-defined and/or configured by the network node. The UE evaluates and reports results to the network node if the UE meets the obtained one or more relaxed measurement criteria on all cells in the GOCs.

In some embodiments, the UE is configured (e.g., based on pre-defined rule and/or configured by the network) to evaluate whether it meets the relaxed measurement criteria (which may be pre-defined or configured by the network) on a subset (Sb) of cells in a GOCs. In one embodiment, Sb comprises one cell, e.g., SpCell. The UE further obtains one or more relaxed measurement criteria based on a rule, which may be pre-defined and/or configured by the network node. The UE evaluates and reports (or transmits) results to the network node if the UE meets the obtained one or more relaxed measurement criteria on at least the subset (Sb) of the cells in the GOCs. The UE may further report results to the network node if the UE does not meet the obtained one or more relaxed measurement criteria for one or more cells in the GOCs.

The network node may further use the received reports from the UE for performing one or more operational tasks allowing the UE to perform relaxed measurement (e.g., configuring the UE with a fewer number of carriers for measurements, a fewer number of cells for measurements, a longer Discontinuous Reception (DRX) cycle, a longer measurement time for measurement) compared to the case when the UE is not allowed to perform relaxed measurement.

Certain embodiments may provide one or more of the following technical advantage(s). Embodiments of the present disclosure may reduce the UE's power consumption and signaling overheads. Embodiments of the present disclosure may enable the UE to evaluate the relaxed measurement criteria in multi-carrier system over a shorter time period.

Figure 1 illustrates one example of a cellular communications system 100 in which embodiments of the present disclosure may be implemented. In the embodiments described herein, the cellular communications system 100 is a 5G system (5GS) including a Next Generation RAN (NG-RAN) and a 5G Core (5GC). In this example, the RAN includes base stations 102-1 and 102-2, which in the 5GS include NR base stations (gNBs) and optionally next generation eNBs (ng-eNBs) (e.g., LTE RAN nodes connected to the 5GC), controlling corresponding (macro) cells 104-1 and 104-2. The base stations 102-1 and 102-2 are generally referred to herein collectively as base stations 102 and individually as base station 102. Also, the base stations 102 are also called as the network node 102 or RAN node 102 or radio access node 102 throughout the present disclosure. Likewise, the (macro) cells 104-1 and 104-2 are generally referred to herein collectively as (macro) cells 104 and individually as (macro) cell 104. The RAN may also include a number of low power nodes 106-1 through 106-4 controlling corresponding small cells 108-1 through 108-4. The low power nodes 106-1 through 106-4 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 108-1 through 108-4 may alternatively be provided by the base stations 102. The low power nodes 106-1 through 106-4 are generally referred to herein collectively as low power nodes 106 and individually as low power node 106. Likewise, the small cells 108-1 through 108-4 are generally referred to herein collectively as small cells 108 and individually as small cell 108. The cellular communications system 100 also includes a core network 110, which in the 5G System (5GS) is referred to as the 5GC. The base stations 102 (and optionally the low power nodes 106) are connected to the core network 110.

The cells illustrated in Figure 1, 104 and 108, may correspond to the cells described in the above section "1.4 Multi-carrier System"; Primary Cell (PCell), Primary Secondary Cell (PSCell), and Secondary Cell (SCell).

The base stations 102 and the low power nodes 106 provide service to wireless communication devices 112-1 through 112-5 in the corresponding cells 104 and 108. The wireless communication devices 112-1 through 112-5 are generally referred to herein collectively as wireless communication devices 112 and individually as wireless communication device 112. In the following description, the wireless communication devices 112 are oftentimes UEs 112, but the present disclosure is not limited thereto.

2.1 Overview

Figure 2 illustrates an example embodiment of the present disclosure. In step 200, the UE 112 evaluates, based on one or more rules, whether one or more relaxed measurement criteria are met on one or more cells in a group of cells. In step 202, the UE 112 sends a report to the network node 102. The report comprises a result of evaluating, based on the one or more rules, whether the one or more relaxed measurement criteria are met on the one or more cells in the group of cells. Optionally, in step 204, after receiving the report from the UE 112, the network node 102 performs one or more operation tasks. Optionally, in step 206, the network node 102 sends (e.g., configures) the one or more rules (e.g., one or more parameters related to the one or more rules) to the UE 102 (e.g., prior to the evaluation in step 200 as shown in Figure 2). Optionally, in step 208, the network node 102 sends a message to the UE 102, which instructs the UE 102 to evaluate the relaxed measurement criteria (e.g., prior to the evaluation in step 200 as shown in Figure 2).

Detailed features of the above steps of Figure 2 are described below. It will be described how the UE 112 handles the report sent to the network for Radio Resource Management (RRM) measurement relaxation criteria fulfillment. The report may be referred to herein as the "RRM relaxation report" or simply the "report."

It will be described how the UE 112 considers the "cells" of the UE 112. As described in the background section above, with the carrier aggregation feature, the UE 112 may be configured with multiple serving cells. However, serving cells of the UE 112 may also be activated or deactivated. When it herein says that the UE 112 is performing an action considering the "cells" of the UE 112, it means that the UE 112 may consider all serving cells of the UE 112, meaning regardless of the activation/deactivation-state. However, it would also be possible that the UE 112 considers only the currently activated serving cells, meaning that if it says, for example, that the UE 112 considers all cells when determining whether to send the report, the UE 112 may consider only the activated serving cells, but not the deactivated serving cells.

The UE 112 performs measurements on one or more downlink (DL) and/or uplink (UL) Reference Signal (RS) of one or more cells in different UE activity states (e.g., RRC idle state, RRC inactive state, and RRC connected state). The measured cell may belong to or operate on the same carrier frequency as of the serving cell (e.g., intrafrequency carrier) or it may belong to or operate on a different carrier frequency as of the serving cell (e.g., non-serving carrier frequency). Examples of the RS are discovery signal or Discovery Reference Signal (DRS), Channel State Information Reference Signal (CSI-RS), Cell-specific Reference Signal (CRS), Demodulation Reference Signal (DM RS), Sounding Reference Signal (SRS), signals in Synchronization Signal (SS)/ Physical Broadcast Channel (PBCH) block (SSB), Primary Synchronization Signal (PSS), and Secondary Synchronization Signal (SSS). Each SSB carries NR-PSS, NR-SSS and NR- PBCH in four successive symbols.

One or multiple SSBs are transmitted in one SSB burst which is repeated with certain periodicity (e.g., 5 milliseconds (ms), 10 ms, 20 ms, 40 ms, 80 ms and 160 ms). The UE 112 is configured with information about the SSB on cells of certain carrier frequency by one or more SS/PBCH block Measurement Timing Configuration (SMTC) configurations. The SMTC configuration comprises parameters such as SMTC periodicity, SMTC occasion length in time or duration, and SMTC time offset with respect to reference time (e.g., serving cell's System Frame Network (SFN)). Therefore, SMTC occasion may also occur with certain periodicity (e.g., 5 ms, 10 ms, 20 ms, 40 ms, 80 ms and 160 ms).

A measurement may also be referred to herein as an "RRM measurement." The measurement may be used for one or more procedures, e.g., mobility, positioning, SelfOrganizing Network (SON), and Minimization of Drive Test (MDT). Examples of measurements are cell identification (e.g. Physical Cell Identity (PCI) acquisition, cell detection), Reference Symbol Received Power (RSRP), Reference Symbol Received Quality (RSRQ), secondary synchronization RSRP (SS-RSRP), SS-RSRQ, SINR, RS-SINR, SS-SINR, CSI-RSRP, CSI-RSRQ, acquisition of system information (SI), cell global ID (CGI) acquisition, Reference Signal Time Difference (RSTD), UE RX-TX time difference measurement, radio link quality, Radio Link Monitoring (RLM), which comprises Out of Synchronization (out of sync) detection and In Synchronization (in-sync) detection, Layer-1 RSRP (Ll-RSRP), Layer-1 SINR (Ll-SINR).

The term "relaxed measurement (RM)" or "relaxed RRM measurement" used herein refers to performing a certain measurement, which is: (a) associated with one or more relaxed requirements compared to those associated with the normal measurement, and/or (b) associated with one or more reduced measurement configuration parameters compared to those associated with the normal mode of operation of that measurement.

2.2 Method of Configuring the UE to Evaluate the RRM Relaxation

In one embodiment, the UE 112 is configured (e.g., in step 206 of the process of Figure 2) with one or more rules (e.g., one or more parameters related to one or more rules) to evaluate whether one or more relaxed measurement criteria is met or fulfilled on one or more cells in a group of cells (GOCs), which comprises at least two cells. The number of cells in GOCs may be dynamic which is created and modified autonomously in the UE 112 over time as the Multi-Connectivity (MuC) configuration changes. The UE 112 may be configured with one or more GOCs. For example, the UE 112 may be configured with j number of GOCs denoted by set G = [Gl, G2, G3, Gj] where each GOCs, Gj, in set G may comprise at least two cells. The rules may be predefined and/or configured by the network node 102. The one or more rules, which is the information (e.g., cell ID, carrier frequency, and FR) about the one or more cells for which the measurement criteria is to be evaluated by the UE 112, may be pre-defined in a memory of the UE 102. Alternatively, as illustrated in Figure 2 (step 206), the UE 102 may receive the one or more rules (e.g., one or more parameters related to the one or more rules) from the network node 102, thus the UE 102 is configured by the network node 102. Examples of the rules are disclosed below.

In a first embodiment of the rule, the UE 112 is configured to evaluate whether one or more relaxed measurement criteria are met on all the cells in the GOCs.

• In one embodiment of the rule, the GOCs may contain or may be applicable to any set of cells, e.g., all serving cells of the UE 112.

• In another embodiment of this rule, the GOCs may contain or may be applicable to cells configured for a particular scenario or configured with a specific configuration or cells which are related to each other by certain relation. Examples of the particular scenario, the specific configuration, or relation are: o All cells operating on the same frequency band belong to GOCs (e.g., cells in intra-band multi-carrier operation). In one embodiment, the cells operate on adjacent or contiguous carriers in the same frequency band (e.g., cells in intra-band contiguous multi-carrier operation). In another embodiment, the cells operate on non-adjacent or non-contiguous carriers in the same frequency band (e.g., cells in intra-band non-contiguous multi-carrier operation). o All cells operating on adjacent carriers in the frequency domain belong to GOCs. In one embodiment, the adjacent or contiguous carriers may belong to the same frequency band (e.g., cells in intra-band contiguous multi-carrier operation). In another embodiment, the adjacent carriers may belong to or distributed over two or more frequency bands. o All cells operating on the same FR belong to GOCs. Examples of FR are FR1 and FR2. In one embodiment, the frequency of carriers in FR1 is smaller than the frequency of carriers in FR2. In one embodiment, FR1 comprises frequencies between 410-7125 MHz; and FR2 comprises frequencies between 24-71 GHz. o All cells operating in the same cell group (CG) in multi-connectivity belong to GOCs, e.g., all cells in the MCG, all cells in the SCG. o All cells operating in the same Timing Advance Group (TAG) belong to GOCs, e.g., all cells in a primary TAG (PTAG), all cells in a secondary TAG (STAG), all cells in a primary secondary TAG (PSTAG).

In a second embodiment of the rule, the UE 112 is configured to evaluate whether one or more relaxed measurement criteria are met on a Sb of cells in the GOCs. The Sb may be pre-defined and/or configured by the network node 102. The cells in the Sb may be dynamic, so those cells are created and modified autonomously in the UE 112 over the time as the MuC configuration changes.

• In one embodiment, the Sb of the cells may comprise one cell. In one embodiment, one cell may be any cell in the GOCs. In another embodiment, one cell may be a particular cell in the GOCs, e.g., SpCell.

• In another embodiment, the Sb of the cells may comprise one cell per frequency band.

• In another embodiment, the Sb of the cells may comprise cells operating on the same frequency band.

• In another embodiment, the Sb of the cells may comprise cells operating on the same FR.

• In another embodiment, the Sb of the cells may comprise cells operating in the same CG in multi-connectivity, e.g., all cells in an MCG, all cells in a SCG.

• In another embodiment, the Sb of the cells may comprise cells operating in the same TAG belong to GOCs, e.g., all cells in a primary TAG (PTAG), all cells in a STAG, all cells in a PSTAG.

• In another embodiment, the Sb may comprise at least one particular type of cell or at least one cell with specific characteristics or properties or configuration.

Examples of such cells are: o A SpCell, a PCell, and a PSCell. o A serving cell configured for sending an uplink signal or a particular type of UL signals (e.g., Physical Random Access Channel (PRACH), Physical Uplink Control Channel (e.g., PUCCH)). For example, a SCell with PUCCH or a PUCCH SCell. o A cell whose bandwidth is largest among all the cells in the Sb or in the GOCs. o A cell whose bandwidth is above a certain threshold. o A cell operating on one or more of: a particular carrier frequency, a particular frequency band and a particular FR (e.g., FR1, FR2). For example, it may be a cell operating on the lowest carrier frequency in a frequency domain, a cell operating on the lowest frequency band in the frequency domain, or a cell operating on FR1.

2.3 Which Cells to Consider for Triggering the RRM Relaxation Report

As illustrated in Figure 2 (step 200), the UE 112 evaluates whether the UE 112 meets one or more relaxed measurement criteria on one or more cells in the GOCs configured in the above embodiment (section 2.2). The UE 112 may obtain information about one or more relaxed measurement criteria based on one or more rules before the evaluation. The rules for the relaxed measurement criteria may be pre-defined and/or configured by the network node 102. Examples of the relaxed measurement criteria are described in the above "1.3 Relaxed measurements section.

In one embodiment, if the UE 112 is configured with the first rule described in the embodiment in section 2.2 (e.g., evaluate if all cells in GOCs to meet relaxation criteria), then the UE 112 sends the report to the network node 102 when all cells fulfill the configured relaxed measurement criterion or condition. This would mean that if the UE 112 should trigger a report, e.g., in response to the measurement (e.g., RSRP, SS- SINR, SS-RSRQ) being above a certain threshold (which may be interpreted as the UE 112 is close to the cell center (i.e., not at cell edge)), the UE 112 would trigger the report only if the measured value of each cell in the GOCs is above a threshold.

In this embodiment, the UE 112 may further be required to evaluate and report the results of the evaluation within a certain time period (Tl) starting from a reference time ("Trefl"). As illustrated in Figure 2 (step 208), optionally, the UE 112 may receive a message from the network node 102 to evaluate the relaxed measurement criteria. In one embodiment, Trefl is the time when the UE 112 has received a message from the network node 102 to evaluate the relaxed measurement criteria on all cells in GOCs. In another embodiment, Trefl is the time which occurs at a future time after the reception of the message from the network node 102 to evaluate the relaxed measurement criterion on all cells in GOCs. The future time, Trefl, may be configured as a certain time resource occurring in the future such as a System Frame Number (SFN) number XI, a slot number X2, or a subframe number X3 of a certain serving cell. The evaluation time period C'Tl") may further depend on the number of cells in the GOCs, as their frequency characteristics are exemplified in the above section 2.2. For example, T1 increases with the increase in the number of cells in GOCs or if they belong to same or different frequencies. In another embodiment, T1 is larger than a certain threshold ("Hl") if the number of cells in GOCs is above a certain threshold ("H2"). The evaluation time period C'Tl") may further depend on the type of or characteristics cells in the GOCs, e.g., cells belonging to the same band. The UE 112 may be further required to evaluate the criteria with a certain periodicity (e.g., every Nth DRX cycle or every 2 seconds), upon a certain event of cell change or change in measured value.

In another embodiment, if the UE 112 is configured with the second rule described in the above section 2.2 (e.g., evaluate if at least Sb of cells (in a particular example, just one cell) in GOCs to meet relaxation criteria), then the UE 112 sends the report to the network node 102 when the Sb of cells (e.g., one cell) fulfills the configured relaxed measurement criterion or condition. This would mean that if the UE 112 is configured with two cells but only one of the cells fulfills the relaxed measurement criterion or condition, the UE 112 would send the report, even if the other cell does not fulfill the condition, i.e., the Sb of cells comprises only one cell.

If the relaxed measurement criterion for at least the Sb in the GOCs fulfills the criterion, then the UE 112 may or may not evaluate the relaxed measurement criterion for the remaining cells in the GOCs. In this embodiment, the UE 112 may further be required to evaluate and report the results of the evaluation within a certain time period C'T2") starting from a reference time ("Tref2").

In one embodiment, Tref2 is the time when the UE 112 has received a message from the network node 102 to evaluate the relaxed measurement criterion on the Sb of cells in GOCs. In another embodiment, Tref2 is the time that occurs at a future time after the reception of the message from the network node 102 to evaluate the relaxed measurement criterion on the Sb of cells in GOCs. The future time, Tref2, may be configured as a time resource occurring in the future such as a SFN number Yl, a slot number Y2, or a subframe number Y3 of a certain serving cell. The evaluation time period C'T2") may further depend on the number of cells in the Sb belonging to the GOCs. For example, T2 increases with the increase in the number of cells in the Sb. In another embodiment, T2 is larger than a certain threshold C'H3") if the number of cells in the Sb is above a certain threshold C'H4"). The evaluation time period C'T2") may further depend on the type of or characteristics cells in the Sb, for example, cells belonging to the same band.

In one embodiment, the evaluation time periods, T1 and T2, may be the same. In another embodiment, T1 and T2 may be different. In one specific embodiment, T1 > T2. The parameters, Tl, T2, Trefl, Tref2, XI, X2, X3, Yl, Y2, Y3, Hl, H2, H3 and H4 may be predefined and/or configured by the network node 102.

2.4 Per Cell Thresholds

As described in the previous sections, the UE 112 may be configured to trigger a report, for example, in response to a signal metric (e.g., a signal strength metric such as RSRP, a signal quality metric such as RSRQ, SINR) being above a certain threshold.

In one embodiment, the network would configure the UE 112 with multiple thresholds. For example, the UE 112 may receive one (set of) threshold(s) per serving cell. For example, in a scenario of two carriers, where the UE 112 has a PCell and an SCell, the UE 112 may have one threshold to determine if the PCell fulfills the condition to transmit the report, and another threshold to determine if the SCell fulfills the relaxed measurement criterion or condition.

2.5 Content of the Report in Multi-Carrier Scenarios

The UE 112 configured with multiple cells may indicate, in the report, information relevant for the multi-carrier scenario where the UE 112 is located in. For example, the UE 112 may indicate for which cells the relaxed measurement criteria are fulfilled. That may be indicated with a set of flags where each flag is associated with a serving cell. The flags could be implemented by using a bitmap where each bit in the bitmap is associated with a cell of a certain identity. For example, the first bit in the bitmap corresponds to a serving cell with index 0.

The UE 112 may further transmit, to the network node 102, information about the cell(s), which meet the relaxed measurement criterion but do not belong to the Sb. The UE 112 may further transmit, to the network node 102, information about the cell(s) which do not meet the relaxed measurement criterion. The UE 112 may further transmit, to the network node 102, information about the relaxed measurement criteria, which are not met for certain cells.

The report may be sent to the network node 102 via a signaling message, e.g. LI message (e.g., PUCCH, PUSCH), PRACH (e.g., 2-step Random Access Channel (RACH)), Medium Access Control (MAC), and RRC.

As illustrated in Figure 2 (step 204), the network node 102 may further use the received reports from the UE 112 for performing one or more operational tasks. For example, if the received report indicates that the UE 112 meets one or more relaxed measurement criteria, the operational tasks in the network node 102 may comprise one or more of the following:

• Configuring the UE 112 allowing the UE 112 to perform relaxed measurements e.g., perform measurement over longer time period compared to the case when the UE 112 to is not allowed to perform relaxed measurements.

• Reconfiguring the current relaxation factors to allow even more relaxation, e.g., modifying the relaxation factor for 2 to 4.

• Adapting one or more measurement configuration parameters, e.g., o Configuring the UE 112 with a fewer number of carriers for measurements compared to the case when the UE 112 is not allowed to perform relaxed measurements. o Configuring the UE 112 with a fewer number of cells for measurements compared to the case when the UE 112 is not allowed to perform relaxed measurements. o Configuring the UE 112 with a fewer number of resources for measurements (e.g., fewer resources for Radio Link Monitoring (RLM) and a link recovery procedure) compared to the case when the UE 112 is not allowed to perform relaxed measurements. Examples of the resources are the RS such as SSBs and CSI-RS. o Configuring the UE 112 with a DRX cycle. o Configuring the UE 112 with a longer DRX cycle compared to the case when the UE 112 is not allowed to perform relaxed measurements. o Configuring the UE 112 to perform a measurement over a longer measurement time compared to the case when the UE 112 to is not allowed to perform relaxed measurements. 2.6 Actions based on the Report in Multi-Carrier System

Based on the information received from the UE 112 indicating for which cells the relaxation criteria are not fulfilled, the network node 102 may perform one or more of following operational tasks: (a) disabling the measurement relaxation for the indicated cells; (b) reconfiguring the current relaxation factors, so that UE 112 shall fulfill more stringent requirements, e.g. modifying the relaxation factor for 4 to 2; (c) configuring more cells/carriers or measurement resources; (d) when the information received from the UE 112 (GOCs on same carrier) states that the UE 112 fulfils RRM relaxation in the PCell, the NW will let the UE 112 do relaxed measurements for the entire GOCs; and (e) when the UE 112 instead only has a SCell that fulfils criteria, allow relaxed measurements in the SCell only.

Additional Description

Figure 3 is a schematic block diagram of a radio access node 300 according to some embodiments of the present disclosure. Optional features are represented by dashed boxes. The radio access node 300 may be, for example, a base station 102 or 106 or a network node that implements all or part of the functionality of the base station 102 or gNB described herein. As illustrated, the radio access node 300 includes a control system 302 that includes one or more processors 304 (e.g., Central Processing Units (CPUs), Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs), and/or the like), memory 306, and a network interface 308. The one or more processors 304 are also referred to herein as processing circuitry. In addition, the radio access node 300 may include one or more radio units 310 that each includes one or more transmitters 312 and one or more receivers 314 coupled to one or more antennas 316. The radio units 310 may be referred to or be part of radio interface circuitry. In some embodiments, the radio unit(s) 310 is external to the control system 302 and connected to the control system 302 via, e.g., a wired connection (e.g., an optical cable). However, in some other embodiments, the radio unit(s) 310 and potentially the antenna(s) 316 are integrated together with the control system 302. The one or more processors 304 operate to provide one or more functions of a radio access node 300 as described herein. In some embodiments, the function(s) are implemented in software that is stored, e.g., in the memory 306 and executed by the one or more processors 304. Figure 4 is a schematic block diagram that illustrates a virtualized embodiment of the radio access node 300 according to some embodiments of the present disclosure. This discussion is equally applicable to other types of network nodes. Further, other types of network nodes may have similar virtualized architectures. Again, optional features are represented by dashed boxes.

As used herein, a "virtualized" radio access node is an implementation of the radio access node 300 in which at least a portion of the functionality of the radio access node 300 is implemented as a virtual component(s) (e.g., via a virtual machine(s) executing on a physical processing node(s) in a network(s)). As illustrated, in this example, the radio access node 300 may include the control system 302 and/or the one or more radio units 310, as described above. The control system 302 may be connected to the radio unit(s) 310 via, for example, an optical cable or the like. The radio access node 300 includes one or more processing nodes 400 coupled to or included as part of a network(s) 402. If present, the control system 302 or the radio unit(s) are connected to the processing node(s) 400 via the network 402. Each processing node 400 includes one or more processors 404 (e.g., CPUs, ASICs, FPGAs, and/or the like), memory 406, and a network interface 408.

In this example, functions 410 of the radio access node 300 described herein are implemented at the one or more processing nodes 400 or distributed across the one or more processing nodes 400 and the control system 302 and/or the radio unit(s) 310 in any desired manner. In some particular embodiments, some or all of the functions 410 of the radio access node 300 described herein are implemented as virtual components executed by one or more virtual machines implemented in a virtual environment(s) hosted by the processing node(s) 400. As will be appreciated by one of ordinary skill in the art, additional signaling or communication between the processing node(s) 400 and the control system 302 is used in order to carry out at least some of the desired functions 410. Notably, in some embodiments, the control system 302 may not be included, in which case the radio unit(s) 310 communicate directly with the processing node(s) 400 via an appropriate network interface(s).

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 radio access node 300 or a node (e.g., a processing node 400) implementing one or more of the functions 410 of the radio access node 300 in a virtual environment according to any of the embodiments described herein 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 signal, a radio signal, or a computer readable storage medium (e.g., a non-transitory computer readable medium such as memory).

Figure 5 is a schematic block diagram of the radio access node 300 according to some other embodiments of the present disclosure. The radio access node 300 includes one or more modules 500, each of which is implemented in software. The module(s) 500 provide the functionality of the radio access node 300 described herein. This discussion is equally applicable to the processing node 400 of Figure 4 where the modules 500 may be implemented at one of the processing nodes 400 or distributed across multiple processing nodes 400 and/or distributed across the processing node(s) 400 and the control system 302.

Figure 6 is a schematic block diagram of a wireless communication device 600 according to some embodiments of the present disclosure. An example of the wireless communication device 600 is the UE 102. As illustrated, the wireless communication device 600 includes one or more processors 602 (e.g., CPUs, ASICs, FPGAs, and/or the like), memory 604, and one or more transceivers 606 each including one or more transmitters 608 and one or more receivers 610 coupled to one or more antennas 612. The transceiver(s) 606 includes radio-front end circuitry connected to the antenna(s) 612 that is configured to condition signals communicated between the antenna(s) 612 and the processor(s) 602, as will be appreciated by on of ordinary skill in the art. The processors 602 are also referred to herein as processing circuitry. The transceivers 606 are also referred to herein as radio circuitry. In some embodiments, the functionality of the wireless communication device 600 described above may be fully or partially implemented in software that is, e.g., stored in the memory 604 and executed by the processor(s) 602. Note that the wireless communication device 600 may include additional components not illustrated in Figure 6 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 like and/or any other components for allowing input of information into the wireless communication device 600 and/or allowing output of information from the wireless communication device 600), 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 wireless communication device 600 according to any of the embodiments described herein 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 signal, a radio signal, or a computer readable storage medium (e.g., a non-transitory computer readable medium such as memory).

Figure 7 is a schematic block diagram of the wireless communication device 600 according to some other embodiments of the present disclosure. The wireless communication device 600 includes one or more modules 700, each of which is implemented in software. The module(s) 700 provide the functionality of the wireless communication device 600 described herein.

Any appropriate 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 microcontrollers, 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 includes program instructions for executing one or more telecommunications and/or data communications protocols as well as instructions for carrying out one or more of the techniques described herein. In some implementations, the processing circuitry may be used to cause the respective functional unit to perform corresponding functions according one or more embodiments of the present disclosure.

While processes in the figures may show a particular order of operations performed by certain embodiments of the present disclosure, 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.).

Those skilled in the art will recognize improvements and modifications to the embodiments of the present disclosure. All such improvements and modifications are considered within the scope of the concepts disclosed herein.

Claims

1. A method performed by a User Equipment, UE, (112) configured for multi-carrier operation in a cellular communications system (100), comprising: evaluating (200), based on one or more rules, whether one or more relaxed measurement criteria are met on one or more cells in a Group of Cells, GOCs, configured for the UE (112) for multi-carrier operation; and sending (202) a report to the network node (102), the report comprising a result of evaluating, based on the one or more rules, whether the one or more relaxed measurement criteria are met on the one or more cells in the GOCs.

2. The method of claim 1, wherein the multi-carrier operation is one of Carrier Aggregation, Dual Connectivity, or Multi-Connectivity.

3. The method of any of claims 1 or 2, wherein the GOCs is a Master Cell Group, MCG, or a Secondary Cell Group, SCG.

4. The method of claim 1 or 2, wherein the GOCs comprises a Primary Cell, PCell, and one or more Secondary Cells, SCells.

5. The method of claim 4, wherein the one or more cells in the GOCs evaluated based on the one or more rules comprise: (a) the PCell, (b) at least one of the one or more SCells, or (c) both the PCell and at least one of the one or more SCells.

6. The method of claim 1 or 2, wherein the GOCs comprises a Primary Secondary Cell, PSCell, and one or more Secondary Cells, SCells.

7. The method of claim 6, wherein the one or more cells in the GOCs evaluated based on the one or more rules comprise: (a) the PSCell, (b) at least one of the one or more SCells, or (c) both the PSCell and at least one of the one or more SCells.

8. The method of claim 1 or 2, wherein the one or more cells in the GOCs evaluated based on the one or more rules consist of all cells in the GOCs.

9. The method of claim 1 or 2, wherein the one or more cells in the GOCs evaluated based on the one or more rules consist of a subset of the one or more cells in the GOCs.

10. The method of claim 9, wherein the subset of the one or more cells in the GOCs is predefined or configured.

11. The method of claim 9, wherein the subset of the one or more cells in the GOCs dynamically changes over time as configurations of the UE for multi-carrier operation change.

12. The method of any of claims 9 to 11, wherein the subset of the one or more cells in the GOCs evaluated based on the one or more rules consist of a single cell.

13. The method of any of claims 9 to 11, wherein the subset of the one or more cells in the GOCs evaluated based on the one or more rules consist of all cells in a same Master Cell Group, MCG, or all cells in a same Secondary Cell Group, SCG.

14. The method of any of claims 1 to 13, wherein the one or more relaxed measurement criteria are met when signal quality of the UE is above a signal quality threshold.

15. The method of any of claims 1 to 14, wherein the one or more relaxed measurement criteria are criteria that must be met in order for the UE to perform relaxed measurements when in connected stated and configured for multi-carrier operation.

16. The method of claim 15, wherein the relaxed measurements are relaxed Radio Resource Management, RRM, measurements.

17. The method of claim 15 or 16, wherein the relaxed measurements have one or more relaxed requirements comprising a relaxed measurement time, a relaxed measurement accuracy, or a relaxed measurement reporting periodicity.

18. The method of claim 15 or 16, wherein the relaxed measurements have one or more relaxed requirements comprising a relaxed evaluation period.

19. The method of claim 15 or 16, wherein the relaxed measurements have one or more relaxed requirements comprising a relaxed measurement time which is a function of a normal measurement time and a scaling factor.

20. The method of any of claims 1 to 19, wherein one or more parameters related to the one or more rules are received (206) from the network node (102).

21. The method of any of claims 1 to 19, wherein the one or more rules are predefined.

22. The method of any of claims 1 to 21, wherein the one or more relaxed measurement criteria relate to mobility of the UE (112).

23. The method of claim 22, wherein evaluating, based on the one or more rules, whether the one or more relaxed measurement criteria are met on the one or more cells in the GOCs comprises evaluating whether the mobility of the UE (112) is below a threshold on the one or more cells in the GOCs.

24. The method of any of claims 1 to 21, wherein the one or more relaxed measurement criteria relate to the UE (112) located not at an edge of the cell.

25. The method of claim 24, wherein evaluating, based on the one or more rules, whether the one or more relaxed measurement criteria are met on the one or more cells in the GOCs comprises evaluating whether a signal strength of the UE (112) is above a threshold on the one or more cells in the GOCs.

26. The method of any of claims 1 to 25, further comprising receiving (208), from the network node (102), a message to perform the evaluating (200) the one or more relaxed measurement criteria, wherein the report is sent (202) to the network node (102) within a time period (Tl) from a reference time (Trefl).

27. The method of claim 26, wherein the reference time (Trefl) is the time when the UE (112) receives (208), from the network node (102), the message to perform the evaluating (200) the one or more relaxed measurement criteria.

28. The method of claim 26, wherein the reference time (Trefl) is the time which occurs at a future time after the UE (112) receives (208), from the network node (102), the message to perform the evaluating (200) the one or more relaxed measurement criteria.

29. The method of any of claims 1 to 28, wherein the report comprises at least one of (a) the UE's indication for which cells the relaxed measurement criteria are fulfilled,

(b) information about cells in the GOCs which meet the relaxed measurement criteria but do not belong to a subset of the GOCs, and (c) information about the relaxed measurement criteria that are not met for certain cells.

30. The method of any of claims 1 to 29, wherein the UE (112) sends (202) the report to the network node (102) via a signaling message, which correspond to at least one of (a) layer 1 message, (b) a Physical Random Access Channel, PRACH, message,

(c) a Medium Access Control, MAC, message, and (d) a Radio Resource Control, RRC, message.

31. A User Equipment, UE, (112) in a multi-carrier system with a network node (102), adapted to: evaluate (200), based on one or more rules, whether one or more relaxed measurement criteria are met on one or more cells in a group of cells, GOCs; and send (202) a report to the network node (102), the report comprising a result of evaluating, based on the one or more rules, whether the one or more relaxed measurement criteria are met on the one or more cells in the GOCs.

32. The UE of claim of 31, wherein the UE (112) is further adapted to perform the method of any of claims 2 to 30.

33. A User Equipment, UE, (112) in a multi-carrier system with a network node (102), comprising: 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 configured to cause the UE (112) to: evaluate (200), based on one or more rules, whether one or more relaxed measurement criteria are met on one or more cells in a group of cells, GOCs; and send (202) a report to the network node (102), the report comprising a result of evaluating, based on the one or more rules, whether the one or more relaxed measurement criteria are met on the one or more cells in the group of GOCs.

34. The UE of claim 33, wherein the processing circuitry is further configured to cause the UE (112) to perform the method of any of claims 2 to 30.

35. A method performed by a network node (102) in a multi-carrier system with a User Equipment, UE, (112) comprising: configuring (206) one or more parameters related to one or more rules to the UE (112); and receiving (202) a report from the UE (112), the report comprising a result of an evaluation at the UE, based on the one or more rules, whether one or more relaxed measurement criteria are met on one or more cells in a group of cells, GOCs.

36. The method of claim 35 further comprising performing (204) one or more operational tasks in response to the report received from the UE (112).

37. The method of claim 35 or 36 further comprising sending (208), to the UE (112), a message instructing the UE (112) to evaluate, based on the one or more rules, whether the one or more relaxed measurement criteria are met on the one or more cells in the GOCs.

38. The method of any of claims 36 to 37, wherein the one or more operational tasks comprise at least one of (a) configuring the UE (112) such that the UE (112) is allowed to perform a relaxed measurement; (b) reconfiguring a relaxation factor to allow relaxation of one or more measurement requirements at the UE (112); and (c) adapting one or more measurement configuration parameters for the UE (112).

39. The method of any of claims 36 to 37, wherein the one or more operational tasks comprise, for a cell where the relaxed measurement criteria are not fulfilled, at least one of (a) disabling relaxed measurement for the cell at the UE (112); (b) reconfiguring an existing relaxation factor for relaxed measurements for the cell at the UE (112); and (c) configuring more resources.

40. A network node (102) for a multi-carrier system with a User Equipment, UE, (112), the network node (102) adapted to: configure (206) one or more parameters related to one or more rules to the UE (112); and receive (202) a report from the UE (112), the report comprising a result of an evaluation at the UE, based on the one or more rules, whether one or more relaxed measurement criteria are met on one or more cells in a group of cells, GOCs.

41. The network node (102) of claim of 40, wherein the network node (102) is further adapted to perform the method of any of claims 36 to 39.

42. A network node (102) for a multi-carrier system with a User Equipment, UE, (112), the network node (102) comprising processing circuitry configured to cause the network node (102) to: configure (206) one or more parameters related to one or more rules to the UE (112); and receive (202) a report from the UE (112), the report comprising a result of an evaluation at the UE, based on the one or more rules, whether one or more relaxed measurement criteria are met on one or more cells in a group of cells, GOCs.

43. The network node (102) of claim 42, wherein the processing circuitry is further configured to cause the network node (102) to perform the method of any of claims 36 to 39.