Conditional handover timer in network energy saving mode

Abstract

A method of operating a communication device in a wireless communications network that includes a network node configured to provide a serving cell, the network node being capable of entering a network energy saving, NES, mode. The method comprises receiving a NES-based conditional handover, CHO, candidate cell list from the network node. The method further comprises receiving an indication that the network node will enter the NES mode; and subsequent to receiving the indication that the network node will enter the NES mode, initiating a NES-based CHO procedure. The method further comprises receiving an indication of an amount of time between the indication that the network node will enter the NES mode being received and a time that the network node will enter the NES mode from the network node. The method comprises initiating the NES-based CHO procedure comprises initiating the NES-based CHO procedure before the amount of time has elapsed.

Description

CONDITIONAL HANDOVER TIMER IN NETWORK ENERGY SAVING MODETECHNICAL FIELD

[0001] The present disclosure is related to wireless communication systems and more particularly to conditional handover (“CHO”) in network energy saving (“NES”) mode.BACKGROUND

[0002] FIG. 1 illustrates an example of a new radio (“NR”) network (e.g., a 5th Generation (“5G”) network) including a 5G core (“5GC”) network 130, network nodes 120a-b (e.g., 5G base station (“gNB”)), multiple communication devices 110 (also referred to as user equipment (“UE”)).

[0003] Network (“NW”) energy consumption in NR increases with respect to long term evolution (“LTE”) due to more complex hardware (“HW”) (e.g., higher bandwidth (“BW”) and a larger number of transceivers). This can be particularly evident when the NW operates in higher frequencies. Hence it can be important for the NW to turn ON / OFF unused HW modules during inactivity times. For example, in frequency range 2 (“FR2”), an NR gNB can be configured with up to 64 beams and transmit up to 64 synchronization signal blocks (“SSBs”). This implies 64 ports with many transceiver chains involved. Such SSBs can be transmitted every 20ms during 5ms windows for the sake of providing coverage to potential UEs even if there actually are no UEs present in the cell.

[0004] Handovers are normally triggered when a user equipment (“UE”) (also referred to herein as a communication device) is at the cell edge and experiences poor radio conditions. If the UE enters poor radio conditions quickly the conditions may already be so poor that the actual handover procedure may be hard to execute. In some examples, if the uplink (“UL”) is already bad it may lead to the network not being able to detect the measurement report transmitted by the UE and hence the network cannot initiate the handover procedure. In additional or alternative examples, downlink (“DL”) problems may lead to the handover command (e.g., the RRCReconfiguration message with a reconfigurationWithSync field) being unable to successfully reach the UE. In poor radio conditions the DL message can be segmented, which increases the risk of retransmissions with an increased risk that the message doesn’t reach the UE in time. Failed transmission of handover command is a common reason for unsuccessful handovers.

[0005] To improve mobility robustness and address the issues above, a concept known as conditional handover (“CHO”) is introduced in the third generation partnership project (“3GPP”) Release 16. A key idea in CHO is that transmission and execution of the handovercommand are separated. This allows the handover command to be sent earlier to UE when the radio conditions are still good, thus increasing the likelihood that the message is successfully transferred. The execution of the handover command is done at later point in time based on an associated execution condition. The execution condition is typically in the form a threshold (e.g., signal strength of candidate target cell becomes X dB better than the serving cell (sometimes referred to herein as an A3 event) or signal strength of serving cell becomes worse than X dBm and signal strength of candidate target cell becomes better than Y dBm (sometimes referred to herein as an A5 event)).

[0006] In some embodiments herein, a cell for which conditional handover (or other conditional mobility procedure) is configured is denoted “candidate target cell” or “potential target cell”. Similarly, a radio network node controlling a candidate / potential target cell is denoted “candidate target node” or “potential target node.” In a sense, once the CHO execution condition has been fulfilled for a candidate / potential target cell and CHO execution towards this candidate / potential target cell has been triggered, this cell is no longer “potential” or a “candidate” in the normal senses of the words, since it is no longer uncertain whether the CHO will be executed towards it. Hence, after the CHO execution condition has been fulfilled / triggered, the concerned candidate / potential target cell is herein sometimes referred to as “target cell”.

[0007] FIG. 2 illustrates an example of a signaling flow for a conditional handover in NR. The conditional handover is split into three portions: handover preparation 210; handover execution 220; and handover completion 230.

[0008] At blocks 201, the UE and source gNB have an established connection and are exchanging user data. At block 211, a measurement report is transmitted by the UE to the source gNB. At block 212, due to some trigger (e.g., the measurement report from the UE), the source gNB decides to configure one or multiple CHO candidate cells. The threshold used for the measurement reporting should be chosen lower than the one in the handover execution condition. This allows the serving cell to prepare the handover when the radio link to the UE is still stable. The execution of the handover is done at a later point in time (and threshold) which is considered optimal for the handover execution.

[0009] At block 213, the source gNB sends a CHO REQUEST to the target gNB with necessary information to prepare a conditional handover at the target side. The information includes among other things the current source configuration and the UE capabilities.

[0010] At block 214, the target gNB prepares the handover and responds with a CHO REQUEST ACKNOWLEDGE to the source gNB, which includes the handover command (a RRCReconfiguration message) to be sent to the UE and later executed if / when the executioncondition would be fulfilled. The handover command includes information needed by the UE to access the target cell, e.g., random access configuration, a new C-RNTI assigned by the target access node and security parameters enabling the UE to calculate the target security key so the UE can send the handover complete message (a RRCReconfigurationComplete message).

[0011] At blocks 215-216, to configure a candidate target cell the source node sends the CHO configuration (e.g., a RRCReconfiguration message) to the UE which contains the handover command and the associated execution condition. The handover command (also an RRCReconfiguration message) is the same as the one generated by the target node during the handover preparation phase in blocks 213-214 and the execution condition is generated by the source node.

[0012] At blocks 222-223, if the execution condition is met, the UE executes the handover by performing random access and sending the handover complete message (e.g., an RRCReconfigurationComplete message) to the target node.

[0013] At block 224, the target gNB sends a HANDOVER SUCCESS message to the source gNB indicating the UE has successfully established the target connection.

[0014] At blocks 225-226, upon reception of the handover success indication, the source gNB stops scheduling any further DL or UL data to the UE and sends a SN STATUS TRANSFER message to the target gNB indicating the latest PDCP SN transmitter and receiver status. At block 227, the source node now also starts to forward User Data to the target node.

[0015] At block 231, Upon receiving the handover complete message, the target node can start exchanging user data with the UE. The target node also requests the AMF to switch the DL data path from the UPF from the source node to the target node (not shown). At block 232, once the path switch is completed the target node sends the UE CONTEXT RELEASE to the source node.

[0016] The conditional handover concept in 3GPP Rel-16 has been generalized into a generic conditional reconfiguration framework, where a UE may be configured in advance with other types of reconfigurations which can be executed by an RRCReconfiguration message (in NR) or an RRCConnectionReconfiguration message (in LTE) upon a certain associated condition is triggered.

[0017] The Conditional PSCell Addition (“CPA”) and Conditional PSCell Change (“CPC”) are examples of two other types of reconfigurations, which use the conditional reconfiguration framework but operating on the PSCell in the Multi-Radio Dual Connectivity (“MR-DC”) scenario. In CPA and CPC, when an execution condition is met, rather than a handover, a PSCell Addition (in case of CPA) or a PSCell change (in case of CPC) is executed.

[0018] Procedure delays are specified below for all procedures that can command a conditional handover. When the UE receives a radio resource control (“RRC”) message implying conditional handover the UE shall be ready to start the transmission of the new uplink physical random access channel (“PRACH”) channel within DCHO seconds from the end of the last TTI containing the RRC command.DCHO = TRRC + TEvent DU + T measure “I" Tinterrupt “I" TcHO execution Where:TRRC is the RRC procedure delay;TEvent DU is the delay uncertainty which is the time from when the UE successfully decodes a conditional handover command until a condition exists at the measurement reference point which will trigger the conditional handover;Tmeasure is the measurements time;Teno execution is the conditional execution preparation time; andTintemipt is the interruption time.

[0019] FIG. 3 illustrates an example of the procedure flow for conditional handover. To remember that the handover condition may be met before / during the RRC signaling configuration and / or decoding.

[0020] In Rel-18, Network Energy Saving (“NES”) based CHO is introduced with the following agreements. It is agreed to make enhancement in CHO procedure based on the source cell entering “NES mode”. For source cell CHO framework, a reference scenario is assumed where the UE has already performed CHO conditions evaluation by the time the source cell starts some “NES-mode.” As a baseline, UE initiates CHO evaluation upon receiving the CHO configuration.

[0021] Furthermore, a CHO solution can consider NES mode of at least source cell. A specific NES CHO execution condition can be provided based on source cell NES mode. A new LI signaling will not be introduced for the purpose of CHO. Event A3, A4, and A5 can be configured as a CHO execution condition in the NES scenario.

[0022] CHO triggers can be supported for the use case of turning off the cell. At least for cell DTX / DRX, time-based CHO is not to be considered in NES. Using an indication in SIB1 for triggering NES CHO execution condition will not be considered.

[0023] Group common DCI format 2-X is reused to notify the UE that source cell is entering NES mode. One bit of DCI 2-X is added to trigger both use cases of Cell DTX / DRX activation and cell turning off. RAN2 send LS to RANI to request this signaling change.

[0024] FIG. 4 illustrates an example of a NES scenario for using the CHO framework when a cell (e.g., a capacity / booster cell) provided by a first network node 420a is about to turn offand the UEs 110 need to be handed over to another cell provided by a second network node 420b, typically a coverage / overlapping cell on another carrier. In the cell which is about to turn off, dedicated messages are transmitted to UEs one by one whereby they are handed over to the coverage cell. Through this CHO framework, instead the UEs are provided CHO configuration earlier (e.g., already upon connection setup), and when the cell is about to turn off, a common DCI 2_9 including a specific bit / indicator is transmitted to trigger the handover commonly for the UEs 110.SUMMARY

[0025] There currently exist certain challenges. When a user equipment (“UE”) (also referred to herein as a communication device) is configured with a conditional handover (“CHO”), the UE needs to start measuring on the target cells and keep measuring throughout the connection period so that it is prepared for a potential handover scenario (e.g., if it suddenly at any point in time experiences poor coverage such as when it gets close to cell edge). The applicant has appreciated however that this scenario is quite different from the network energy saving (“NES”) scenario in which the network (“NW”) in a controlled manner and at a known point in time decides to turn off a cell. It is quite wasteful in terms of energy to let the UE measure on, for example, another carrier, throughout the whole connection just in case the NW would decide to turn off the cell. It may even be that the NW does not turn off the cell in which case the UE measurement efforts were in vain.

[0026] The “turn-off ’ / NES indication is sent to the UEs via a DCI transmission. The NES CHO conditions are only relevant from this point onwards so that the UE can leave the cell and, for example, handover to the coverage cell. However, the UE cannot wait for the DCI before it initiates the CHO measurements as it does not know how long after the DCI the NW may turn off the cell. The UE may need to spend a long time to perform condition checking and CHO execution. Therefore, based on current agreements, the UE has no other choice than to keep measuring at all times throughout the connection before the DCI.

[0027] Certain aspects of the disclosure and their embodiments may provide solutions to these or other challenges.

[0028] The present invention is defined in the independent claims, to which reference is now directed.

[0029] According to the present invention, there is provided a method of operating a communication device in a wireless communications network that includes a network node configured to provide a serving cell. The network node is capable of entering a network energy saving, NES, mode. The method comprises receiving aNES-based conditional handover, CHO,candidate cell list from the network node. The method further comprises receiving an indication that the network node will enter the NES mode. The method further comprises, subsequent to receiving the indication that the network node will enter the NES mode, initiating a NES-based CHO procedure. The method further comprises receiving an indication of an amount of time between the indication that the network node will enter the NES mode being received and a time that the network node will enter the NES mode from the network node. The initiating the NES- based CHO procedure comprises initiating the NES-based CHO procedure before the amount of time has elapsed.

[0030] Receiving the indication that the network node will enter the NES mode may comprise receiving a downlink control information, DCI, comprising the indication that the network node will enter the NES mode. The DCI may be a group common DCI.

[0031] In some embodiments, initiating the NES-based CHO procedure may comprise completing the NES-based CHO procedure before the amount of time has elapsed.

[0032] The method may further comprise performing a measurement associated with each candidate cell in the NES-based CHO candidate cell list before the amount of time has elapsed.

[0033] In some embodiments, performing a measurement associated with each candidate cell in the NES-based CHO candidate cell list before the amount of time has elapsed may comprise, when the amount of time is greater than a threshold time, initiating the measurement associated with each candidate cell in the NES-based CHO candidate cell list subsequent to receiving the indication that the network node will enter the NES mode.

[0034] In some embodiment, performing a measurement associated with each candidate cell in the NES-based CHO candidate cell list before the amount of time has elapsed may comprise, when the amount of time is less than a threshold time, initiating the measurements prior to receiving the indication that the network node will enter the NES mode.

[0035] Advantageously, in some embodiments, the indication of the amount of time may be received prior to the indication that the network node will enter the NES mode.

[0036] In some embodiments, the indication of the amount of time may be received in a RadioResource Control, RRC, message. For example, the indication of the amount of time may be received in Information Element, IE, CondTriggerConfig.

[0037] In other embodiments, the indication of the amount of time may be received in the DCI comprising the indication that the network node will enter the NES mode.

[0038] The indication of the amount of time may indicate an amount of time from a plurality of candidate amounts of time.

[0039] The amount of time may be an integer of time, for example with unit of a milli-second.

[0040] According to the present invention, there is also provided a method of operating a network node in a wireless communications network that includes a communication device. The network node is configured to provide a serving cell to the communication device and the network node is capable of entering a network energy saving, NES, mode. The method comprises transmitting a NES-based conditional handover, CHO, candidate cell list to the communication device. The method further comprises transmitting, to the communication device, an indication that the network node will enter the NES mode. The method further comprises transmitting, to the wireless communication device, an indication of an amount of time between the indication that the network node will enter the NES mode being received by the communication device and a time that the network node will enter the NES mode; and after the amount of time elapsing, entering the NES mode.

[0041] The indication of the amount of time may be transmitted prior to the indication that the network node will enter the NES mode.

[0042] In some embodiments, entering the NES mode may comprise switching off the serving cell.

[0043] According to the present invention, there is further provided a communication device. The communication device is configured to perform operations comprising: receiving a NES- based conditional handover, CHO, candidate cell list from the network node; receiving an indication that the network node will enter the NES mode; and subsequent to receiving the indication that the network node will enter the NES mode, initiating a NES-based CHO procedure. The communication device is further configured to perform an operation comprising receiving an indication of an amount of time between the indication that the network node will enter the NES mode being received and a time that the network node will enter the NES mode from the network node. The operation comprising initiating the NES- based CHO procedure comprises initiating the NES-based CHO procedure before the amount of time has elapsed.

[0044] There is further provided a network node configured to perform operations comprising: transmitting a NES-based conditional handover, CHO, candidate cell list to the communication device, and transmitting an indication that the network node will enter the NES mode to the communication device. The network node is further configured to perform operations comprising transmitting, to the wireless communication device, an indication of an amount of time between the indication that the network node will enter the NES mode being received by the communication device and a time that the network node will enter the NES mode; and, after the amount of time elapsing, entering the NES mode.

[0045] Certain aspects of these embodiments may provide technical advantages.

[0046] In some embodiments, the UE can save energy since it does not constantly have to measure before the actual NES CHO trigger.

[0047] In additional or alternative embodiments, a fast conditional handover for NES mode is introduced. The UE can speed up the conditional handover procedure to avoid radio link failure (“RLF”) due to the serving cell entering the NES mode. The network can also have confidence to enter the NES mode based on such fast conditional handover defined.

[0048] In additional or alternative embodiments, the UE does not need to be configured with gaps (configured for the sake of CHO NES) interrupting the connected mode constantly during the connection. Instead the gaps are only relevant after the NES CHO trigger.BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this application, illustrate certain non-limiting embodiments of inventive concepts. In the drawings:

[0050] FIG. 1 is a schematic diagram illustrating an example of a 5thgeneration (“5G”) network;

[0051] FIG. 2 is a signal flow diagram illustrating an example of a conditional handover in NR;

[0052] FIG. 3 is a procedural flow illustrating an example of a reference flow for conditional handover;

[0053] FIG. 4 is a schematic diagram illustrating an example of a 5G network prepared for a NES CHO;

[0054] FIG. 5 is a flow chart illustrating an example of operations performed by a communication device;

[0055] FIG. 6 is a flow chart illustrating an example of operations performed by a network node;

[0056] FIG. 7 is a flow chart illustrating an example of operations performed by a communication device according to embodiments;

[0057] FIG. 8 is a flow chart illustrating an example of operations performed by a network node according to embodiments;

[0058] FIG. 9 is a block diagram of a communication system in accordance with some embodiments;

[0059] FIG. 10 is a block diagram of a user equipment in accordance with some embodiments; and

[0060] FIG. 11 is a block diagram of a network node in accordance with some embodiments.DETAILED DESCRIPTION

[0061] Some of the embodiments contemplated herein will now be described more fully with reference to the accompanying drawings. Embodiments are provided by way of example to convey the scope of the subject matter to those skilled in the art, in which examples of embodiments of inventive concepts are shown. Inventive concepts may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of present inventive concepts to those skilled in the art. It should also be noted that these embodiments are not mutually exclusive. Components from one embodiment may be tacitly assumed to be present / used in another embodiment.

[0062] Additional information is described in Appendix A.

[0063] As mentioned above, FIG. 4 illustrates an example of a NES scenario for using the CHO framework when a cell (e.g., a capacity / booster cell) provided by a first network node 420a is about to turn off and the UEs 110 need to be handed over to another cell provided by a second network node 420b, typically a coverage / overlapping cell on another carrier. In the cell which is about to turn off, dedicated messages could be transmitted to UEs one by one whereby they are handed over to the coverage cell. However, through the CHO framework, instead the UEs are provided CHO configuration earlier (e.g., already upon connection setup), and when the cell is about to turn off, a common DCI 2_9 including a specific bit / indicator is transmitted to trigger the handover commonly for the UEs 110.

[0064] The UE performs measurements on one or more DL and / or UL reference signal (“RS”) of one or more cells in different UE activity states (e.g., RRC idle state, RRC inactive state, or RRC connected state). The measured cell may belong to or operate on the same carrier frequency as of the serving cell (e.g. intra-frequency carrier) or it may belong to or operate on different carrier frequency as of the serving cell (e.g., non-serving carrier frequency). The non-serving carrier may be called as inter-frequency carrier if the serving and measured cells belong to the same radio access technology (“RAT”) bit different carriers. The non-serving carrier may be called as inter-RAT carrier if the serving and measured cells belong to different RATs. Examples of downlink RS are signals in SSB, channel state information RS (“CSI-RS”), cell specific reference signal (“CRS”), demodulation reference signal (“DMRS”), primary synchronization signal (“PSS”), secondary synchronization signal(“SSS”), signals in SS / PBCH block (“SSB”), discovery reference signal (“DRS”), and positioning reference signal (“PRS”). Examples of uplink RS are signals in SRS or DMRS.

[0065] Each SSB carries NR-PSS, NR-SSS, and NR-PBCH in 4 successive symbols. One or multiple SSBs are transmit in one SSB burst which is repeated with certain periodicity (e.g., 5 ms, 10 ms, 20 ms, 40 ms, 80 ms and 160 ms). The UE is configured with information about SSB on cells of certain carrier frequency by one or more SS / PBCH block measurement timing configuration (“SMTC”) configurations. The SMTC configuration comprising parameters such as SMTC periodicity, SMTC occasion length in time or duration, SMTC time offset with regards to reference time (e.g., serving cell’s system frame number (“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).

[0066] Examples of measurements are cell identification (e.g., physical cell identifier (“PCI”) acquisition, PSS / SSS detection, cell detection, or cell search), Reference Symbol Received Power (“RSRP”), Reference Symbol Received Quality (“RSRQ”), secondary synchronization RSRP (“SS-RSRP”), SS-RSRQ, signal interference-to-noise ratio (“SINR”), RS-SINR, SS-SINR, CSI-RSRP, CSI-RSRQ, received signal strength indicator (“RSSI”), acquisition of system information (“SI”), cell global ID (“CGI”) acquisition, Reference Signal Time Difference (“RSTD”), UE RX-TX time difference measurement, Radio Link Monitoring (“RLM”), which consists of Out of Synchronization (out of sync) detection and In Synchronization (in-sync) detection..

[0067] The UE can be configured by the network (e.g., via RRC message) with measurement configuration and measurement reporting configuration (e.g., measurement gap pattern, carrier frequency information, types of measurements (e.g., RSRP), higher layer filtering coefficient, time to trigger report, or reporting mechanism (e.g., periodic, event triggered reporting, or event triggered periodic reporting)).

[0068] The measurements are done for various purposes. Some example measurement purposes are: UE mobility (e.g., cell change, cell selection, cell reselection, handover, or RRC connection re-establishment), UE positioning or location determination self-organizing network (“SON”), minimization of drive tests (“MDT”), operation and maintenance (“O&M”), and network planning and optimization.

[0069] As mentioned above, when a user equipment (“UE”) (also referred to herein as a communication device) is configured with a conditional handover (“CHO”), the UE needs to start measuring on the target cells and keep measuring throughout the connection period so that it is prepared for a potential handover scenario (e.g., if it suddenly at any point in time experiences poor coverage such as when it gets close to cell edge). However, the applicant hasappreciated that this scenario is quite different from the network energy saving (“NES”) scenario in which the network (“NW”) in a controlled manner and at a known point in time decides to turn off a cell. It is quite wasteful in terms of energy to let the UE measure on, for example, another carrier, throughout the whole connection just in case the NW would decide to turn off the cell. It may even be that the NW does not turn off the cell in which case the UE measurement efforts were in vain.

[0070] The “turn-off ’ / NES indication is sent to the UEs via a DCI transmission. The NES CHO conditions are only relevant from this point onwards so that the UE can leave the cell and, for example, handover to the coverage cell. However, according to existing agreements, the UE cannot wait for the DCI before it initiates the CHO measurements as it does not know how long after the DCI the NW may turn off the cell. The UE may need to spend a long time to perform condition checking and CHO execution. Therefore, the UE has no other choice than to keep measuring at all times throughout the connection before the DCI.

[0071] Various aspects herein describe a procedure that applies to a NES-based conditional handover scenario where the NW indicates that it is entering the NES mode.

[0072] In some examples, the UE is requested to handover to target cells as fast as possible to avoid unnecessary RLF due to serving cell switch off or Cell DTX.

[0073] In some examples, a conditional handover timer is defined for the NES-triggered CHO scenario. The UE is requested to execute the conditional handover within the timer. The timer can be pre-defined or configured by NW, such as RRC or DCI. As such, it will be known to the UE how long time there is between the DCI reception and the NW NES state entrance (e.g., if the NW turns off the cell some seconds after the DCI indication). The UE then knows whether the time is long enough to delay its measurement efforts on potential target cells until after the DCI, or whether it needs to measure already before.

[0074] In additional or alternative examples, the CHO timer applies only to candidate target cell which is configured with only NES specific CHO execution condition. The execution condition may mean, the candidate target cell is configured with NES specific thresholds in the event configuration. Or, that the measld is tagged or otherwise indicated to be NES specific and this candidate target cell is not configured with another measld not tagged or indicated to be NES specific.

[0075] In additional or alternative examples, since a network can make antenna muting / power reduction decisions after it receives CSI feedback for different hypotheses (or sub-configurations) from a UE, the UE may start to perform measurement for conditional HO when it receives the DCI / MAC-CE that is used to trigger CSI feedback for different hypotheses(or sub-configurations). In this way, UE can be prepared for CHO before the actual tum- off / NES indicator sent to UE but not perform conditional HO too early.

[0076] Herein, the term “node” is used which can be a network node or a user equipment (“UE”). Examples of network nodes are NodeB, base station (“BS”), multi-standard radio (“MSR”) radio node such as MSR BS, eNodeB, gNodeB, MeNB, SeNB, location measurement unit (“LMU”), integrated access backhaul (“IAB”) node, network controller, radio network controller (“RNC”), base station controller (“BSC”), relay, donor node controlling relay, base transceiver station (“BTS”), Central Unit (e.g., in a gNB), Distributed Unit (e.g., in a gNB), Baseband Unit, Centralized Baseband, C-RAN, access point (“AP”), transmission points, transmission nodes, transmission reception point (“TRP”), RRU, RRH, nodes in distributed antenna system (“DAS”), core network node (e.g., MSC or MME), O&M, OSS, SON, or positioning node (e.g., E-SMLC).

[0077] Further, herein, the non-limiting term “UE” refers to any type of wireless device communicating with a network node and / or with another UE in a cellular or mobile communication system. Examples of UE are target device, device to device (“D2D”) UE, vehicular to vehicular (“V2V”), machine type UE, MTC UE or UE capable of machine to machine (“M2M”) communication, PDA, tablet, mobile terminals, smart phone, laptop embedded equipment (“LEE”), laptop mounted equipment (“LME”), or USB dongles.

[0078] The term radio access technology, (“RAT”), may refer to any RAT (e.g., UTRA, E- UTRA, narrow band internet of things (“NB-IoT”), WiFi, Bluetooth, next generation RAT, New Radio (“NR”), 4G, 5G, NR NTN, loT NTN, or LTE NTN). Any of the equipment denoted by the term node, network node or radio network node may be capable of supporting a single or multiple RATs.

[0079] The term signal or radio signal used herein can be any physical signal or physical channel. Examples of DL physical signals are reference signal (“RS”) such as PSS, SSS, CSI- RS, DMRS signals in SS / PBCH block (“SSB”), discovery reference signal (“DRS”), CRS, or PRS. RS may be periodic (e.g., RS occasion carrying one or more RSs may occur with certain periodicity (e.g., 20 ms, or 40 ms)). The RS may also be aperiodic. Each SSB carries NR-PSS, NR-SSS and NR-PBCH in 4 successive symbols. One or multiple SSBs are transmit in one SSB burst which is repeated with certain periodicity e.g. 5 ms, 10 ms, 20 ms, 40 ms, 80 ms and 160 ms. The UE is configured with information about SSB on cells of certain carrier frequency by one or more SS / PBCH block measurement timing configuration (“SMTC”) configurations. The SMTC configuration comprising parameters such as SMTC periodicity, SMTC occasion length in time or duration, SMTC time offset with regards to reference time (e.g., serving cell’s SFN).Therefore, SMTC occasion may also occur with certain periodicity (e.g., 5 ms, 10 ms, 20 ms, 40ms, 80 ms and 160 ms). Examples of UL physical signals are reference signal such as SRS or DMRS. The term physical channel refers to any channel carrying higher layer information (e.g., data, control). Examples of physical channels are PBCH, NPBCH, PDCCH, PDSCH, sPUCCH, sPDSCH, sPUCCH, sPUSCH, MPDCCH, NPDCCH, NPDSCH, E-PDCCH, PUSCH, PUCCH, orNPUSCH.

[0080] Various embodiments herein aim to help the UE to conserve energy and potentially postpone its measurement efforts until a CHO is triggered for NES. In some embodiments, it speeds up the CHO execution procedure in NES mode compared with traditional CHO.

[0081] In some embodiments, a UE is configured with aNES-based CHO candidate cell list and a timer which indicates the time between the NES indication (e.g., DCI 2 9 including the NES bit) and the time the NW enters NES mode (e.g., from the DCI until cell actually turns off). The UE receives the group common DCI to indicate the source cell is entering NES mode. The UE executes the measurement to evaluate the channel condition. The UE executes the NES- based CHO. In some examples, after parsing the NES mode DCI, the UE shall perform the conditional handover. For example, the cell will switch off. Or the cell will enter NES mode, but the legacy UE cannot support NES mode.

[0082] In additional or alternative embodiments, after the NW configures the NES -based candidate cell list but before receiving the NES DCI indication, the UE does not perform measurement to evaluate the candidate cells in NES-based CHO candidate cell list. The NES- based CHO delay will start from UE receiving the DCI indication and includes the uncertainty from UE successfully decoding the DCI until aNES-based condition exists.

[0083] In additional or alternative embodiments, after the NW configures the NES-based candidate cell list, the UE will perform measurement to evaluate the candidate cells. Once UE receives the NES DCI indication, the UE will execute the CHO to any target cell which meets the condition configured by the NW.

[0084] Aspects associated with the CHO Execution Timer are described below. In some embodiments, when the UE receives the group common DCI to indicate the source cell is entering the NES mode, the UE evaluates the candidate cells (e.g., from the NES-based CHO candidate cell list) and handover to the target cell which fulfills the condition as soon as possible. Especially, when the DCI further indicates the serving cell will go to switch off.

[0085] In some embodiments, to serve the intended purpose, a timer which henceforth is referred as TimeToNESMode can be provided to the UE. In additional or alternative embodiments, the UE may start the timer TimeToNESMode upon the UE receiving the group common DCI from the network node, after that, the UE completes cell change before the TimeToNESMode expires.

[0086] In some examples, the UE finishes the CHO evaluation and executes handover to the target cell with respect to the embodiments introduced in this disclosure within the left time interval of the TimeToNESMode provided the UE is configured with CHO configuration and receives the group common DCI. Alternatively, the UE shall start cell change or at the least complete partial CHO procedure, e.g., the RSRP / RSRQ measurements meet conditions for CHO, before expiry of the TimeToNESMode.

[0087] In additional or alternative embodiments, after the UE completes cell change (e.g., CHO) before expiry of the TimeToNESMode, the UE shall stop the TimeToNESMode. In some examples, if the UE fails to complete cell change (e.g., CHO) due to some reasons e.g., failure detect target cell, radio link failure or fail complete RACH procedure, before expiry of the TimeToNESMode, then the UE shall declare handover failure and perform cell selection (or any similar action such as go to RRC idle etc.) and stop the TimeToNESMode.

[0088] In additional or alternative embodiments, if the TimeToNESMode is shorter than the typical time it takes for the UE to measure and evaluate the CHO candidates after the DCI, the UE instead initiates the measurement / evaluation procedures for the target cells already before the DCI (e.g., already from the point in time the CHO configuration is received.

[0089] In some examples, if there are more than one CHO configuration, the UE shall complete cell change with respect to at the least one CHO configuration before expiry of the TimeToNESMode, otherwise, the UE shall declare handover failure and perform cell selection (or any similar action such as go to RRC idle etc.).

[0090] The TimeToNESMode indicates the time interval left for handover / CHO before the serving / source cell enters the NES mode. When the TimeToNESMode expires, it is expected or indicates that the serving cell will enter the NES mode, for example, the serving cell will switch off.

[0091] In some examples, the length / duration of TimeToNESMode can be pre-defined, such as 10s in the spec. In additional or alternative examples, the timer TimeToNESMode can be differentiated by the target cells belonging to FR1 or FR2 scenarios. For example, the timer to target cell in FR1 can be Xms, and the timer to the target cells in FR2 can be Yms which consider the beam sweeping in evaluation.

[0092] In additional or alternative embodiments, the length / duration of TimeToNESMode can be further indicated by the NW in various approaches. In some examples, when NW indicates the UE the source cell is entering NES mode by group common DCI, NW can further indicate the length / duration of the TimeToNESMode together and start the TimeToNESMode. In additional or alternative examples, the length / duration of TimeToNESMode is comprised in aRRC message, which is signaled to the UE by the NW. The timer can be configured for example in IE CondTriggerConfig or it may be associate to a specific Measld.

[0093] The length / duration of TimeToNESMode provided by the NW may be one of the the candidate TimeToNESMode list, e.g., {... , 500 ms, 1000 ms, 2000 ms, 10000 ms, ... }, or an integer with unit of milli-second determined by the NW.

[0094] In additional or alternative embodiments, if the TimeToNESMode has a value of 0, it means that the NW will enter NES mode immediately after the DCI indication. UE shall perform handover to any cell regardless of whether the conditional handover condition is met. In one example, UE shall perform handover to any cell or best cell based on cell’s quality, e.g. one of detectable cells or the cell having highest RSRP / RSRQ regardless of whether the conditional handover condition is met.

[0095] In additional or alternative embodiments, when the TimeToNESMode is expired, the UE shall perform handover to any cell or best cell based on cell’s quality regardless of whether the conditional handover condition is met.

[0096] In additional or alternative embodiments, at the moment the cell switch off or Cell DTX / DRX, the UE shall perform handover to any cell or best cell based on cell’s quality regardless of whether the conditional handover condition is met.

[0097] In some examples, the source NW may request the candidate target NWs in CHO to provide the start time instant of the TimeToNESMode ( i.e., the time instant when the candidate target NWs sends the group common DCI in the corresponding cells) respectively and the length / duration of the TimerNESCHO or alternatively the left time interval of the TimeToNESMode when the candidate target NWs receive the request provided the candidate target NWs support NES mode and enable the group common DCI. Wherein, the request to the candidate target NWs and the feedback provided by the candidate target NWs can be comprised in the CHO request and the CHO request acknowledge signaling flow by extension between the source NW and the candidate target NWs in CHO.

[0098] In some examples, on account of the feedback by the candidate target NWs, the source NW may determine the candidate target NWs which meets certain criteria, e.g., the left intervals of the TimeToNESMode are larger than a threshold, and send the list of them in the RRCReconfiguration message to the UE. In another way, the source NW provides the candidate target NWs associated with the respective TimeToNESMode in the RRCReconfiguration message to the UE, the UE may determine the target NWs to be switched which the left intervals of the TimeToNESMode are larger than a threshold.

[0099] In Rel-18, it has already been agreed that in order to let gNB have a better NES decision, gNB can send DCI / MAC-CE to UE to trigger UE sending CSI report for differentantenna muting / power reduction hypotheses. After gNB received the CSI report of all relevant hypotheses, it will make the final decision to go into NES mode, e.g. mute some antenna or reduce transmission power.

[0100] Therefore, it may not be necessary for UE to start to perform measurement of the candidate cells when it receives the CHO condition. Instead, UE may start to perform measurement of the candidate cells when it receives the DCI / MAC-CE that triggers UE to feedback CSI for different hypotheses (or sub-configurations in RRC signaling).

[0101] Operations of the communication device 200 (implemented using the structure of Figure 2) will now be discussed with reference to the flow chart of FIG. 5 according to some embodiments of inventive concepts. For example, modules may be stored in memory 210 of Figure 2, and these modules may provide instructions so that when the instructions of a module are executed by respective communication device processing circuitry 202, communication device 200 performs respective operations of the flow chart.

[0102] FIG. 5 illustrates an example of operations performed by a communication device in a wireless communications network that includes a network node. In some embodiments, the network node is configured to provide a serving cell to the communication device. The network node may be capable of entering a NES mode in which the serving cell is switched to off.

[0103] At block 510, processing circuitry 202 determines a NES-based CHO candidate cell list. In some embodiments, determining the NES-based CHO candidate cell list includes receiving the NES-based CHO candidate cell list from the network node.

[0104] At block 520, processing circuitry 202 determines an amount of time between an indication that the network node will enter the NES mode being communicated and a time that the network node will enter the NES mode. In some examples, the time that the indication that the network node will enter the NES mode is communicated is the time that the indication that the network node will enter the NES mode is received by the communication device.

[0105] In some examples, determining the amount of time between the indication that the network node will enter the NES mode being communicated and the time that the network node will enter the NES mode includes receiving an indication of the amount of time from the network node.

[0106] In additional or alternative examples, determining the amount of time between the indication that the network node will enter the NES mode being communicated and the time that the network node will enter the NES mode includes determining the amount of time between the indication that the network node will enter the NES mode being communicated and the time that the network node will enter the NES mode based on a frequency range of a candidate cell in the NES-based CHO candidate cell list.

[0107] At block 530, processing circuitry 202 determines whether the amount of time is less than a threshold amount of time. In some embodiments, the threshold amount of time is based on a time that it takes for the communication device to measure and / or evaluate a NES-based CHO candidate cell.

[0108] At block 540, processing circuitry 202 receives, via communication interface 212, the indication that the network node will enter the NES mode. In some embodiments, receiving the indication that the network node will enter the NES mode includes receiving at least one of group common downlink control information, DCI; and media access control, MAC, control element, CE.

[0109] At block 550, processing circuitry 202 initializes a timer based on the amount of time.

[0110] At block 560, processing circuitry 202 determines a measurement associated with each candidate cell in the NES-based CHO candidate cell list.

[0111] In some examples, determining whether the amount of time is less than the threshold amount of time includes determining that the amount of time is less than the threshold time. Determining the measurement associated with each candidate cell in the NES-based CHO candidate list includes, responsive to determining that the amount of time is less than the threshold time, initiating a measurement associated with a candidate cell in the NES-based CHO candidate list prior to receiving the indication that the network node will enter the NES mode.’

[0112] In additional or alternative examples, determining whether the amount of time is less than the threshold amount of time includes determining that the amount of time is greater than a threshold time. In some examples, determining the measurement associated with each candidate cell in the NES-based CHO candidate list includes, responsive to determining that the amount of time is greater than the threshold time, initiating the measurement associated with each candidate cell in the NES-based CHO candidate list subsequent to receiving the indication that the network node will enter the NES mode.

[0113] At block 570, processing circuitry 202 initiating a NES-based CHO procedure. In some examples, initiating the NES-based CHO procedure includes initiating the NES-based CHO procedure before the amount of time has elapsed.

[0114] In additional or alternative examples, initiating the NES-based CHO procedure includes completing the NES-based CHO procedure before the amount of time has elapsed.

[0115] In additional or alternative examples, initiating the NES-based CHO procedure includes: determining that the amount of time has elapsed; and responsive to determining that the amount of time has elapsed, performing a handover to a cell regardless of whether a condition associated with the NES-based CHO is met.

[0116] At block 580, processing circuitry 202 declares a handover failure. In some examples, declaring the handover failure includes performing cell selection or a similar action such as transitioning to a RRC idle state.

[0117] V arious operations from the flow chart of FIG. 5 may be optional with respect to some embodiments of communication devices and related methods.

[0118] Operations of the network node 300 (implemented using the structure of Figure 3) will now be discussed with reference to the flow chart of FIG. 6 according to some embodiments of inventive concepts. For example, modules may be stored in memory 304 of Figure 3, and these modules may provide instructions so that when the instructions of a module are executed by respective network node processing circuitry 302, network node 300 performs respective operations of the flow chart.

[0119] FIG. 6 illustrates an example of operations performed by a network node in a wireless communications network that includes a communication device. In some embodiments, the network node is configured to provide a serving cell to the communication device. The network node can be capable of entering a NES mode in which the serving cell is switched off.

[0120] At block 610, processing circuitry 302 transmits, via communication interface 306, an indication of a NES-based CHO candidate cell list.

[0121] At block 620, processing circuitry 302 determines an amount of time between the indication that the network node will enter the NES mode being communicated and a time that the network node will enter the NES mode. In some examples, determining the amount of time includes determining the amount of time based on a frequency range of a candidate cell in the NES-based CHO candidate cell list.

[0122] In additional or alternative examples, determining the amount of time includes: receiving information from a target cell in the NES-based CHO candidate cell list; and determining the amount of time based on the information.

[0123] In additional or alternative examples, determining the amount of time includes determining the amount of time based on a frequency range of a candidate cell in the NES-based CHO candidate cell list.

[0124] At block 630, processing circuitry 302 transmits, via communication interface 306, an indication of the amount of time. In some examples, transmitting the indication of the amount of time to the communication device includes transmitting a message to the network node including the indication that the network node will enter the NES mode and the indication of the amount of time.

[0125] At block 640, processing circuitry 302 transmits, via communication interface 306, an indication that the network node will enter the NES mode. In some examples, transmitting the indication that the network node will enter the NES mode includes transmitting at least one of: group common downlink control information, DCI; and media access control, MAC, control element, CE.

[0126] At block 650, processing circuitry 302 receives, via communication interface 306, a report from the communication device.

[0127] At block 660, processing circuitry 302 determines that it is time to enter the NES mode based on the report.

[0128] At block 670, processing circuitry 302 enters the NES mode. In some examples, entering the NES mode includes switching off the serving cell.

[0129] Various operations from the flow chart of FIG. 6 may be optional with respect to some embodiments of network nodes and related methods.

[0130] Figure 7 is a flow chart showing a method of operating a communication device in a wireless communications network that includes a network node configured to provide a serving cell according to embodiments. The network node is capable of entering a network energy saving, NES, mode.

[0131] The method comprises at block 710 receiving a NES-based conditional handover, CHO, candidate cell list from the network node.

[0132] The method further comprises at block 730 receiving an indication that the network node will enter the NES mode.

[0133] The method further comprises, subsequent to receiving at block 730 the indication that the network node will enter the NES mode, at block 740 initiating a NES-based CHO procedure.

[0134] The method further comprises at block 720 receiving an indication of an amount of time between the indication that the network node will enter the NES mode being received and a time that the network node will enter the NES mode from the network node. Block 470, initiating the NES-based CHO procedure, comprises initiating the NES-based CHO procedure before the amount of time has elapsed.

[0135] At block 730 the indication that the network node will enter the NES mode may be comprised within a downlink control information, DCI. This DCI may be a group common DCI.

[0136] In some embodiments block 740, initiating the NES-based CHO procedure, may comprise completing the NES-based CHO procedure before the amount of time has elapsed.

[0137] The method may further comprise at block 745 performing a measurement associated with each candidate cell in the NES-based CHO candidate cell list before the amount of time has elapsed. In some embodiments, block 745 may comprise, when the amount of time is greater than a threshold time, initiating the measurement associated with each candidate cell in the NES-based CHO candidate cell list subsequent to receiving the indication that the network node will enter the NES mode. In some embodiment, in addition or alternatively, block 745 may comprise, when the amount of time is less than a threshold time, initiating the measurement associated with each candidate cell in the NES-based CHO candidate cell list prior to receiving the indication that the network node will enter the NES mode.

[0138] In some embodiments, the indication of the amount of time may be received, at block 720, prior to the indication that the network node will enter the NES mode at block 730.

[0139] In some embodiments, the indication of the amount of time may be received in a RadioResource Control, RRC, message. For example, the indication of the amount of time may be received in Information Element, IE, CondTriggerConfig.

[0140] In other embodiments, the indication of the amount of time may be received in the DCI comprising the indication that the network node will enter the NES mode. Thus, in these embodiments, the indication of the amount of time may be received at the same time as the indication that the network node will enter the NES mode.

[0141] The indication of the amount of time may indicate an amount of time from a plurality of candidate amounts of time. In some examples, the amount of time may be an integer of time with a unit of a milli-second.

[0142] Figure 8 is a flow chart showing a method of operating a network node in a wireless communications network that includes a communication device. The network node is configured to provide a serving cell to the communication device. Further, the network node is capable of entering a network energy saving, NES, mode.

[0143] The method comprises at block 800 transmitting a NES-based conditional handover, CHO, candidate cell list to the communication device.

[0144] The method further comprises at block 840 transmitting an indication that the network node will enter the NES mode to the communication device.

[0145] The method further comprises at block 820 transmitting, to the wireless communication device, an indication of an amount of time between the indication that the network node will enter the NES mode being received by the communication device and a time that the network node will enter the NES mode.

[0146] The method further comprises at block 860, after the amount of time elapsing, entering the NES mode. Entering the NES mode may comprise switching off the serving cell.

[0147] At block 840 the indication that the network node will enter the NES mode may be transmitted within a downlink control information, DCI. This DCI may be a group common

[0148] In some embodiments the indication of the amount of time may be transmitted to the communication device, at block 820, prior to transmitting, at block 840, the indication that the network node will enter the NES mode.

[0149] In some embodiments, the indication of the amount of time may be transmitted in a Radio Resource Control, RRC, message. For example, the indication of the amount of time may be transmitted in Information Element, IE, CondTriggerConfig.

[0150] In other embodiments, the indication of the amount of time may be transmitted in the DCI comprising the indication that the network node will enter the NES mode.

[0151] The indication of the amount of time may indicate an amount of time from a plurality of candidate amounts of time. In some examples, the amount of time may be an integer of time with a unit of a milli-second.

[0152] Figure 9 shows an example of a communication system 100 in accordance with some embodiments.

[0153] In the example, the communication system 100 includes a telecommunication network 102 that includes an access network 104, such as a radio access network (RAN), and a core network 106, which includes one or more core network nodes 108. The access network 104 includes one or more access network nodes, such as network nodes 110a and 110b (one or more of which may be generally referred to as network nodes 110), or any other similar 3rd Generation Partnership Project (3GPP) access node or non-3GPP access point. Moreover, as will be appreciated by those of skill in the art, the network nodes 110 are not necessarily limited to an implementation in which a radio portion and a baseband portion are supplied and integrated by a single vendor. Thus, it will be understood that the network nodes 110 may include disaggregated implementations or portions thereof. For example, in some embodiments, the telecommunication network 102 includes one or more Open-RAN (ORAN) network nodes. An ORAN network node is a node in the telecommunication network 102 that supports an ORAN specification (e.g., a specification published by the O-RAN Alliance, or any similar organization) and may operate alone or together with other nodes to implement one or more functionalities of any node in the telecommunication network 102, including one or more network nodes 110 and / or core network nodes 108.

[0154] Examples of an ORAN network node include an open radio unit (O-RU), an open distributed unit (O-DU), an open central unit (O-CU), including an O-CU control plane (O-CU- CP) or an O-CU user plane (O-CU-UP), a RAN intelligent controller (near-real time or non-real time) hosting software or software plug-ins, such as a near-real time RAN control application (e.g., xApp) or a non-real time RAN automation application (e.g., rApp), or any combination thereof (the adjective “open” designating support of an ORAN specification). The network node may support a specification by, for example, supporting an interface defined by the ORAN specification, such as an Al, Fl, Wl, El, E2, X2, Xn interface, an open fronthaul user plane interface, or an open fronthaul management plane interface. Intents and content-aware notifications described herein may be communicated from a 3GPP network node or an ORAN network node over 3GPP-defined interfaces (e.g., N2, N3) and / or ORAN Alliance-defined interfaces (e.g., Al, 01). Moreover, an ORAN network node may be a logical node in a physical node. Furthermore, an ORAN network node may be implemented in a virtualization environment (described further below) in which one or more network functions are virtualized. For example, the virtualization environment may include an O-Cloud computing platform orchestrated by a Service Management and Orchestration Framework via an 0-2 interface defined by the 0-RAN Alliance. The network nodes 110 facilitate direct or indirect connection of user equipment (UE), such as by connecting wireless devices 112a, 112b, 112c, and 112d (one or more of which may be generally referred to as UEs 112) to the core network 106 over one or more wireless connections. The network nodes 110 facilitate direct or indirect connection of user equipment (UE), such as by connecting UEs 112a, 112b, 112c, and 112d (one or more of which may be generally referred to as UEs 112) to the core network 106 over one or more wireless connections.

[0155] Example wireless communications over a wireless connection include transmitting and / or receiving wireless signals using electromagnetic waves, radio waves, infrared waves, and / or other types of signals suitable for conveying information without the use of wires, cables, or other material conductors. Moreover, in different embodiments, the communication system 100 may include any number of wired or wireless networks, network nodes, UEs, and / or any other components or systems that may facilitate or participate in the communication of data and / or signals whether via wired or wireless connections. The communication system 100 may include and / or interface with any type of communication, telecommunication, data, cellular, radio network, and / or other similar type of system.

[0156] The UEs 112 may be any of a wide variety of communication devices, including wireless devices arranged, configured, and / or operable to communicate wirelessly with the network nodes 110 and other communication devices. Similarly, the network nodes 110 arearranged, capable, configured, and / or operable to communicate directly or indirectly with the UEs 112 and / or with other network nodes or equipment in the telecommunication network 102 to enable and / or provide network access, such as wireless network access, and / or to perform other functions, such as administration in the telecommunication network 102.

[0157] In the depicted example, the core network 106 connects the network nodes 110 to one or more hosts, such as host 116. These connections may be direct or indirect via one or more intermediary networks or devices. In other examples, network nodes may be directly coupled to hosts. The core network 106 includes one more core network nodes (e.g., core network node 108) that are structured with hardware and software components. Features of these components may be substantially similar to those described with respect to the UEs, network nodes, and / or hosts, such that the descriptions thereof are generally applicable to the corresponding components of the core network node 108. Example core network nodes include functions of one or more of a Mobile Switching Center (MSC), Mobility Management Entity (MME), Home Subscriber Server (HSS), Access and Mobility Management Function (AMF), Session Management Function (SMF), Authentication Server Function (AUSF), Subscription Identifier De-concealing function (SIDF), Unified Data Management (UDM), Security Edge Protection Proxy (SEPP), Network Exposure Function (NEF), and / or a User Plane Function (UPF).

[0158] The host 116 may be under the ownership or control of a service provider other than an operator or provider of the access network 104 and / or the telecommunication network 102, and may be operated by the service provider or on behalf of the service provider. The host 116 may host a variety of applications to provide one or more service. Examples of such applications include live and pre-recorded audio / video content, data collection services such as retrieving and compiling data on various ambient conditions detected by a plurality of UEs, analytics functionality, social media, functions for controlling or otherwise interacting with remote devices, functions for an alarm and surveillance center, or any other such function performed by a server.

[0159] As a whole, the communication system 100 of Figure 1 enables connectivity between the UEs, network nodes, and hosts. In that sense, the communication system may be configured to operate according to predefined rules or procedures, such as specific standards that include, but are not limited to: Global System for Mobile Communications (GSM); Universal Mobile Telecommunications System (UMTS); Long Term Evolution (LTE), and / or other suitable 2G, 3G, 4G, 5G standards, or any applicable future generation standard (e.g., 6G); wireless local area network (WLAN) standards, such as the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standards (WiFi); and / or any other appropriate wireless communication standard, such as the Worldwide Interoperability for Microwave Access(WiMax), Bluetooth, Z-Wave, Near Field Communication (NFC) ZigBee, LiFi, and / or any low- power wide-area network (LPWAN) standards such as LoRa and Sigfox.

[0160] In some examples, the telecommunication network 102 is a cellular network that implements 3GPP standardized features. Accordingly, the telecommunications network 102 may support network slicing to provide different logical networks to different devices that are connected to the telecommunication network 102. For example, the telecommunications network 102 may provide Ultra Reliable Low Latency Communication (URLLC) services to some UEs, while providing Enhanced Mobile Broadband (eMBB) services to other UEs, and / or Massive Machine Type Communication (mMTC)ZMassive loT services to yet further UEs.

[0161] In some examples, the UEs 112 are configured to transmit and / or receive information without direct human interaction. For instance, a UE may be designed to transmit information to the access network 104 on a predetermined schedule, when triggered by an internal or external event, or in response to requests from the access network 104. Additionally, a UE may be configured for operating in single- or multi -RAT or multi-standard mode. For example, a UE may operate with any one or combination of Wi-Fi, NR (New Radio) and LTE, i.e. being configured for multi-radio dual connectivity (MR-DC), such as E-UTRAN (Evolved- UMTS Terrestrial Radio Access Network) New Radio - Dual Connectivity (EN-DC).

[0162] In the example, the hub 114 communicates with the access network 104 to facilitate indirect communication between one or more UEs (e.g., UE 112c and / or 112d) and network nodes (e.g., network node 110b). In some examples, the hub 114 may be a controller, router, content source and analytics, or any of the other communication devices described herein regarding UEs. For example, the hub 114 may be a broadband router enabling access to the core network 106 for the UEs. As another example, the hub 114 may be a controller that sends commands or instructions to one or more actuators in the UEs. Commands or instructions may be received from the UEs, network nodes 110, or by executable code, script, process, or other instructions in the hub 114. As another example, the hub 114 may be a data collector that acts as temporary storage for UE data and, in some embodiments, may perform analysis or other processing of the data. As another example, the hub 114 may be a content source. For example, for a UE that is a VR headset, display, loudspeaker or other media delivery device, the hub 114 may retrieve VR assets, video, audio, or other media or data related to sensory information via a network node, which the hub 114 then provides to the UE either directly, after performing local processing, and / or after adding additional local content. In still another example, the hub 114 acts as a proxy server or orchestrator for the UEs, in particular in if one or more of the UEs are low energy loT devices.

[0163] The hub 114 may have a constant / persistent or intermitent connection to the network node 110b. The hub 114 may also allow for a different communication scheme and / or schedule between the hub 114 and UEs (e.g., UE 112c and / or 112d), and between the hub 114 and the core network 106. In other examples, the hub 114 is connected to the core network 106 and / or one or more UEs via a wired connection. Moreover, the hub 114 may be configured to connect to an M2M service provider over the access network 104 and / or to another UE over a direct connection. In some scenarios, UEs may establish a wireless connection with the network nodes 110 while still connected via the hub 114 via a wired or wireless connection. In some embodiments, the hub 114 may be a dedicated hub - that is, a hub whose primary function is to route communications to / from the UEs from / to the network node 110b. In other embodiments, the hub 114 may be a non-dedicated hub - that is, a device which is capable of operating to route communications between the UEs and network node 110b, but which is additionally capable of operating as a communication start and / or end point for certain data channels.

[0164] Figure 10 shows a UE 200 in accordance with some embodiments. In particular, UE 200 may be configured to perform any of the methods described above as performed by a wireless communication device. As used herein, a UE refers to a device capable, configured, arranged and / or operable to communicate wirelessly with network nodes and / or other UEs. Examples of a UE include, but are not limited to, a smart phone, mobile phone, cell phone, voice over IP (VoIP) phone, wireless local loop phone, desktop computer, personal digital assistant (PDA), wireless cameras, gaming console or device, music storage device, playback appliance, wearable terminal device, wireless endpoint, mobile station, tablet, laptop, laptop-embedded equipment (LEE), laptop-mounted equipment (LME), smart device, wireless customer-premise equipment (CPE), vehicle-mounted or vehicle embedded / integrated wireless device, etc. Other examples include any UE identified by the 3rd Generation Partnership Project (3 GPP), including a narrow band internet of things (NB-IoT) UE, a machine type communication (MTC) UE, and / or an enhanced MTC (eMTC) UE.

[0165] A UE may support device-to-device (D2D) communication, for example by implementing a 3GPP standard for sidelink communication, Dedicated Short-Range Communication (DSRC), vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), or vehicle- to-everything (V2X). In other examples, a UE may not necessarily have a user in the sense of a human user who owns and / or operates the relevant device. Instead, a UE may represent a device that is intended for sale to, or operation by, a human user but which may not, or which may not initially, be associated with a specific human user (e.g., a smart sprinkler controller).Alternatively, a UE may represent a device that is not intended for sale to, or operation by, anend user but which may be associated with or operated for the benefit of a user (e.g., a smart power meter).

[0166] The UE 200 includes processing circuitry 202 that is operatively coupled via a bus 204 to an input / output interface 206, a power source 208, a memory 210, a communication interface 212, and / or any other component, or any combination thereof Certain UEs may utilize all or a subset of the components shown in Figure 2. The level of integration between the components may vary from one UE to another UE. Further, certain UEs may contain multiple instances of a component, such as multiple processors, memories, transceivers, transmitters, receivers, etc.

[0167] The processing circuitry 202 is configured to process instructions and data and may be configured to implement any sequential state machine operative to execute instructions stored as machine-readable computer programs in the memory 210. The processing circuitry 202 may be implemented as one or more hardware-implemented state machines (e.g., in discrete logic, field-programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), etc.); programmable logic together with appropriate firmware; one or more stored computer programs, general-purpose processors, such as a microprocessor or digital signal processor (DSP), together with appropriate software; or any combination of the above. For example, the processing circuitry 202 may include multiple central processing units (CPUs).

[0168] In the example, the input / output interface 206 may be configured to provide an interface or interfaces to an input device, output device, or one or more input and / or output devices. Examples of an output device include a speaker, a sound card, a video card, a display, a monitor, a printer, an actuator, an emitter, a smartcard, another output device, or any combination thereof. An input device may allow a user to capture information into the UE 200. Examples of an input device include a touch-sensitive or presence-sensitive display, a camera (e.g., a digital camera, a digital video camera, a web camera, etc.), a microphone, a sensor, a mouse, a trackball, a directional pad, a trackpad, a scroll wheel, a smartcard, and the like. The presence-sensitive display may include a capacitive or resistive touch sensor to sense input from a user. A sensor may be, for instance, an accelerometer, a gyroscope, a tilt sensor, a force sensor, a magnetometer, an optical sensor, a proximity sensor, a biometric sensor, etc., or any combination thereof. An output device may use the same type of interface port as an input device. For example, a Universal Serial Bus (USB) port may be used to provide an input device and an output device.

[0169] In some embodiments, the power source 208 is structured as a battery or battery pack. Other types of power sources, such as an external power source (e.g., an electricity outlet), photovoltaic device, or power cell, may be used. The power source 208 may further includepower circuitry for delivering power from the power source 208 itself, and / or an external power source, to the various parts of the UE 200 via input circuitry or an interface such as an electrical power cable. Delivering power may be, for example, for charging of the power source 208. Power circuitry may perform any formatting, converting, or other modification to the power from the power source 208 to make the power suitable for the respective components of the UE 200 to which power is supplied.

[0170] The memory 210 may be or be configured to include memory such as random access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable readonly memory (EEPROM), magnetic disks, optical disks, hard disks, removable cartridges, flash drives, and so forth. In one example, the memory 210 includes one or more application programs 214, such as an operating system, web browser application, a widget, gadget engine, or other application, and corresponding data 216. The memory 210 may store, for use by the UE 200, any of a variety of various operating systems or combinations of operating systems.

[0171] The memory 210 may be configured to include a number of physical drive units, such as redundant array of independent disks (RAID), flash memory, USB flash drive, external hard disk drive, thumb drive, pen drive, key drive, high-density digital versatile disc (HD-DVD) optical disc drive, internal hard disk drive, Blu-Ray optical disc drive, holographic digital data storage (HDDS) optical disc drive, external mini-dual in-line memory module (DIMM), synchronous dynamic random access memory (SDRAM), external micro-DIMM SDRAM, smartcard memory such as tamper resistant module in the form of a universal integrated circuit card (UICC) including one or more subscriber identity modules (SIMs), such as a USIM and / or ISIM, other memory, or any combination thereof. The UICC may for example be an embedded UICC (eUICC), integrated UICC (iUICC) or a removable UICC commonly known as ‘SIM card.’ The memory 210 may allow the UE 200 to access instructions, application programs and the like, stored on transitory or non-transitory memory media, to off-load data, or to upload data. An article of manufacture, such as one utilizing a communication system may be tangibly embodied as or in the memory 210, which may be or comprise a device-readable storage medium.

[0172] The processing circuitry 202 may be configured to communicate with an access network or other network using the communication interface 212. The communication interface 212 may comprise one or more communication subsystems and may include or be communicatively coupled to an antenna 222. The communication interface 212 may include one or more transceivers used to communicate, such as by communicating with one or more remote transceivers of another device capable of wireless communication (e.g., another UE or a networkT1node in an access network). Each transceiver may include a transmitter 218 and / or a receiver 220 appropriate to provide network communications (e.g., optical, electrical, frequency allocations, and so forth). Moreover, the transmitter 218 and receiver 220 may be coupled to one or more antennas (e.g., antenna 222) and may share circuit components, software or firmware, or alternatively be implemented separately.

[0173] In the illustrated embodiment, communication functions of the communication interface 212 may include cellular communication, Wi-Fi communication, LPWAN communication, data communication, voice communication, multimedia communication, short- range communications such as Bluetooth, near-field communication, location-based communication such as the use of the global positioning system (GPS) to determine a location, another like communication function, or any combination thereof. Communications may be implemented in according to one or more communication protocols and / or standards, such as IEEE 802.11, Code Division Multiplexing Access (CDMA), Wideband Code Division Multiple Access (WCDMA), GSM, LTE, New Radio (NR), UMTS, WiMax, Ethernet, transmission control protocol / intemet protocol (TCP / IP), synchronous optical networking (SONET), Asynchronous Transfer Mode (ATM), QUIC, Hypertext Transfer Protocol (HTTP), and so forth.

[0174] Regardless of the type of sensor, a UE may provide an output of data captured by its sensors, through its communication interface 212, via a wireless connection to a network node. Data captured by sensors of a UE can be communicated through a wireless connection to a network node via another UE. The output may be periodic (e.g., once every 15 minutes if it reports the sensed temperature), random (e.g., to even out the load from reporting from several sensors), in response to a triggering event (e.g., when moisture is detected an alert is sent), in response to a request (e.g., a user initiated request), or a continuous stream (e.g., a live video feed of a patient).

[0175] As another example, a UE comprises an actuator, a motor, or a switch, related to a communication interface configured to receive wireless input from a network node via a wireless connection. In response to the received wireless input the states of the actuator, the motor, or the switch may change. For example, the UE may comprise a motor that adjusts the control surfaces or rotors of a drone in flight according to the received input or to a robotic arm performing a medical procedure according to the received input.

[0176] A UE, when in the form of an Internet of Things (loT) device, may be a device for use in one or more application domains, these domains comprising, but not limited to, city wearable technology, extended industrial application and healthcare. Non-limiting examples of such an loT device are a device which is or which is embedded in: a connected refrigerator or freezer, a TV, a connected lighting device, an electricity meter, a robot vacuum cleaner, a voicecontrolled smart speaker, a home security camera, a motion detector, a thermostat, a smoke detector, a door / window sensor, a flood / moisture sensor, an electrical door lock, a connected doorbell, an air conditioning system like a heat pump, an autonomous vehicle, a surveillance system, a weather monitoring device, a vehicle parking monitoring device, an electric vehicle charging station, a smart watch, a fitness tracker, a head-mounted display for Augmented Reality (AR) or Virtual Reality (VR), a wearable for tactile augmentation or sensory enhancement, a water sprinkler, an animal- or item-tracking device, a sensor for monitoring a plant or animal, an industrial robot, an Unmanned Aerial Vehicle (UAV), and any kind of medical device, like a heart rate monitor or a remote controlled surgical robot. A UE in the form of an loT device comprises circuitry and / or software in dependence of the intended application of the loT device in addition to other components as described in relation to the UE 200 shown in Figure 2.

[0177] As yet another specific example, in an loT scenario, a UE may represent a machine or other device that performs monitoring and / or measurements, and transmits the results of such monitoring and / or measurements to another UE and / or a network node. The UE may in this case be an M2M device, which may in a 3GPP context be referred to as an MTC device. As one particular example, the UE may implement the 3GPP NB-IoT standard. In other scenarios, a UE may represent a vehicle, such as a car, a bus, a truck, a ship and an airplane, or other equipment that is capable of monitoring and / or reporting on its operational status or other functions associated with its operation.

[0178] In practice, any number of UEs may be used together with respect to a single use case. For example, a first UE might be or be integrated in a drone and provide the drone’s speed information (obtained through a speed sensor) to a second UE that is a remote controller operating the drone. When the user makes changes from the remote controller, the first UE may adjust the throttle on the drone (e.g. by controlling an actuator) to increase or decrease the drone’s speed. The first and / or the second UE can also include more than one of the functionalities described above. For example, a UE might comprise the sensor and the actuator, and handle communication of data for both the speed sensor and the actuators.

[0179] Figure 11 shows a network node 300 in accordance with some embodiments. In particular, network node 300 may be configured to perform any of the methods described above as performed by a network node. As used herein, network node refers to equipment capable, configured, arranged and / or operable to communicate directly or indirectly with a UE and / or with other network nodes or equipment, in a telecommunication network. Examples of network nodes include, but are not limited to, access points (APs) (e.g., radio access points), base stations (BSs) (e.g., radio base stations, Node Bs, evolved Node Bs (eNBs), NR NodeBs (gNBs)), O-RAN nodes, or components of an O-RAN node (e.g., intelligent controller, O-RU, O-DU, O- CU).

[0180] Base stations may be categorized based on the amount of coverage they provide (or, stated differently, their transmit power level) and so, depending on the provided amount of coverage, may be referred to as femto base stations, pico base stations, micro base stations, or macro base stations. A base station may be a relay node or a relay donor node controlling a relay. A network node may also include one or more (or all) parts of a distributed radio base station such as centralized digital units and / or remote radio units (RRUs), sometimes referred to as Remote Radio Heads (RRHs). Such remote radio units may or may not be integrated with an antenna as an antenna integrated radio. Parts of a distributed radio base station may also be referred to as nodes in a distributed antenna system (DAS).

[0181] Other examples of network nodes include multiple transmission point (multi -TRP) 5G access nodes, multi-standard radio (MSR) equipment such as MSR BSs, network controllers such as radio network controllers (RNCs) or base station controllers (BSCs), base transceiver stations (BTSs), transmission points, transmission nodes, multi-cell / multicast coordination entities (MCEs), Operation and Maintenance (O&M) nodes, Operations Support System (OSS) nodes, Self-Organizing Network (SON) nodes, positioning nodes (e.g., Evolved Serving Mobile Location Centers (E-SMLCs)), and / or Minimization of Drive Tests (MDTs).

[0182] The network node 300 includes a processing circuitry 302, a memory 304, a communication interface 306, and a power source 308. The network node 300 may be composed of multiple physically separate components (e.g., aNodeB component and a RNC component, or a BTS component and a BSC component, etc.), which may each have their own respective components. In certain scenarios in which the network node 300 comprises multiple separate components (e.g., BTS and BSC components), one or more of the separate components may be shared among several network nodes. For example, a single RNC may control multiple NodeBs. In such a scenario, each unique NodeB and RNC pair, may in some instances be considered a single separate network node. In some embodiments, the network node 300 may be configured to support multiple radio access technologies (RATs). In such embodiments, some components may be duplicated (e.g., separate memory 304 for different RATs) and some components may be reused (e.g., a same antenna 310 may be shared by different RATs). The network node 300 may also include multiple sets of the various illustrated components for different wireless technologies integrated into network node 300, for example GSM, WCDMA, LTE, NR, WiFi, Zigbee, Z-wave, LoRaWAN, Radio Frequency Identification (RFID) or Bluetooth wireless technologies. These wireless technologies may be integrated into the same or different chip or set of chips and other components within network node 300.

[0183] The processing circuitry 302 may comprise a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application-specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software and / or encoded logic operable to provide, either alone or in conjunction with other network node 300 components, such as the memory 304, to provide network node 300 functionality.

[0184] In some embodiments, the processing circuitry 302 includes a system on a chip (SOC). In some embodiments, the processing circuitry 302 includes one or more of radio frequency (RF) transceiver circuitry 312 and baseband processing circuitry 314. In some embodiments, the radio frequency (RF) transceiver circuitry 312 and the baseband processing circuitry 314 may be on separate chips (or sets of chips), boards, or units, such as radio units and digital units. In alternative embodiments, part or all of RF transceiver circuitry 312 and baseband processing circuitry 314 may be on the same chip or set of chips, boards, or units.

[0185] The memory 304 may comprise any form of volatile or non-volatile computer- readable memory including, without limitation, persistent storage, solid-state memory, remotely mounted memory, magnetic media, optical media, random access memory (RAM), read-only memory (ROM), mass storage media (for example, a hard disk), removable storage media (for example, a flash drive, a Compact Disk (CD) or a Digital Video Disk (DVD)), and / or any other volatile or non-volatile, non-transitory device-readable and / or computer-executable memory devices that store information, data, and / or instructions that may be used by the processing circuitry 302. The memory 304 may store any suitable instructions, data, or information, including a computer program, software, an application including one or more of logic, rules, code, tables, and / or other instructions capable of being executed by the processing circuitry 302 and utilized by the network node 300. The memory 304 may be used to store any calculations made by the processing circuitry 302 and / or any data received via the communication interface 306. In some embodiments, the processing circuitry 302 and memory 304 is integrated.

[0186] The communication interface 306 is used in wired or wireless communication of signaling and / or data between a network node, access network, and / or UE. As illustrated, the communication interface 306 comprises port(s) / terminal(s) 316 to send and receive data, for example to and from a network over a wired connection. The communication interface 306 also includes radio front-end circuitry 318 that may be coupled to, or in certain embodiments a part of, the antenna 310. Radio front-end circuitry 318 comprises filters 320 and amplifiers 322. The radio front-end circuitry 318 may be connected to an antenna 310 and processing circuitry 302. The radio front-end circuitry may be configured to condition signals communicated between antenna 310 and processing circuitry 302. The radio front-end circuitry 318 may receive digitaldata that is to be sent out to other network nodes or UEs via a wireless connection. The radio front-end circuitry 318 may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters using a combination of filters 320 and / or amplifiers 322. The radio signal may then be transmitted via the antenna 310. Similarly, when receiving data, the antenna 310 may collect radio signals which are then converted into digital data by the radio front-end circuitry 318. The digital data may be passed to the processing circuitry 302. In other embodiments, the communication interface may comprise different components and / or different combinations of components.

[0187] In certain alternative embodiments, the network node 300 does not include separate radio front-end circuitry 318, instead, the processing circuitry 302 includes radio front-end circuitry and is connected to the antenna 310. Similarly, in some embodiments, all or some of the RF transceiver circuitry 312 is part of the communication interface 306. In still other embodiments, the communication interface 306 includes one or more ports or terminals 316, the radio front-end circuitry 318, and the RF transceiver circuitry 312, as part of a radio unit (not shown), and the communication interface 306 communicates with the baseband processing circuitry 314, which is part of a digital unit (not shown).

[0188] The antenna 310 may include one or more antennas, or antenna arrays, configured to send and / or receive wireless signals. The antenna 310 may be coupled to the radio front-end circuitry 318 and may be any type of antenna capable of transmitting and receiving data and / or signals wirelessly. In certain embodiments, the antenna 310 is separate from the network node 300 and connectable to the network node 300 through an interface or port.

[0189] The antenna 310, communication interface 306, and / or the processing circuitry 302 may be configured to perform any receiving operations and / or certain obtaining operations described herein as being performed by the network node. Any information, data and / or signals may be received from a UE, another network node and / or any other network equipment.Similarly, the antenna 310, the communication interface 306, and / or the processing circuitry 302 may be configured to perform any transmitting operations described herein as being performed by the network node. Any information, data and / or signals may be transmitted to a UE, another network node and / or any other network equipment.

[0190] The power source 308 provides power to the various components of network node 300 in a form suitable for the respective components (e.g., at a voltage and current level needed for each respective component). The power source 308 may further comprise, or be coupled to, power management circuitry to supply the components of the network node 300 with power for performing the functionality described herein. For example, the network node 300 may be connectable to an external power source (e.g., the power grid, an electricity outlet) via an inputcircuitry or interface such as an electrical cable, whereby the external power source supplies power to power circuitry of the power source 308. As a further example, the power source 308 may comprise a source of power in the form of a battery or battery pack which is connected to, or integrated in, power circuitry. The battery may provide backup power should the external power source fail.

[0191] Embodiments of the network node 300 may include additional components beyond those shown in Figure 3 for providing certain aspects of the network node’s functionality, including any of the functionality described herein and / or any functionality necessary to support the subject matter described herein. For example, the network node 300 may include user interface equipment to allow input of information into the network node 300 and to allow output of information from the network node 300. This may allow a user to perform diagnostic, maintenance, repair, and other administrative functions for the network node 300.

[0192] Although the computing devices described herein (e.g., UEs, network nodes, hosts) may include the illustrated combination of hardware components, other embodiments may comprise computing devices with different combinations of components. It is to be understood that these computing devices may comprise any suitable combination of hardware and / or software needed to perform the tasks, features, functions and methods disclosed herein.Determining, calculating, obtaining or similar operations described herein may be performed by processing circuitry, which may process information by, for example, converting the obtained information into other information, comparing the obtained information or converted information to information stored in the network node, and / or performing one or more operations based on the obtained information or converted information, and as a result of said processing making a determination. Moreover, while components are depicted as single boxes located within a larger box, or nested within multiple boxes, in practice, computing devices may comprise multiple different physical components that make up a single illustrated component, and functionality may be partitioned between separate components. For example, a communication interface may be configured to include any of the components described herein, and / or the functionality of the components may be partitioned between the processing circuitry and the communication interface. In another example, non-computationally intensive functions of any of such components may be implemented in software or firmware and computationally intensive functions may be implemented in hardware.

[0193] In certain embodiments, some or all of the functionality described herein may be provided by processing circuitry executing instructions stored on in memory, which in certain embodiments may be a computer program product in the form of a non-transitory computer- readable storage medium. In alternative embodiments, some or all of the functionality may beprovided by the processing circuitry without executing instructions stored on a separate or discrete device-readable storage medium, such as in a hard-wired manner. In any of those particular embodiments, whether executing instructions stored on a non-transitory computer- readable storage medium or not, the processing circuitry can be configured to perform the described functionality. The benefits provided by such functionality are not limited to the processing circuitry alone or to other components of the computing device, but are enjoyed by the computing device as a whole, and / or by end users and a wireless network generally.

[0194] Example Embodiments are included below.

[0195] Embodiment 1. A method of operating a communication device (200) in a wireless communications network that includes a network node configured to provide a serving cell, the network node being capable of entering a network energy saving, NES, mode in which the serving cell will be switched off, the method comprising: determining (510) aNES-based conditional handover, CHO, candidate cell list; receiving (540) the indication that the network node will enter the NES mode; and subsequent to receiving the indication that the network node will enter the NES mode, initiating (570) aNES-based CHO procedure.

[0196] Embodiment 2. The method of Embodiments 1, further comprising: determining (520) an amount of time between the indication that the network node will enter the NES mode and a time that the network node will enter the NES mode.

[0197] Embodiment s. The method of Embodiment 2, wherein determining the amount of time between the indication that the network node will enter the NES mode and the time that the network node will enter the NES mode comprises receiving an indication of the amount of time from the network node.

[0198] Embodiment 4. The method of Embodiment 2, wherein determining the amount of time between the indication that the network node will enter the NES mode and the time that the network node will enter the NES mode comprises determining the amount of time between the indication that the network node will enter the NES mode and the time that the network node will enter the NES mode based on a frequency range of a candidate cell in the NES-based CHO candidate cell list.

[0199] Embodiment s. The method of any of Embodiments 2-4, further comprising: responsive to receiving the indication that the network node will enter the NES mode, initializing (550) a timer based on the amount of time.

[0200] Embodiment 6. The method of any of Embodiments 2-5, further comprising: determining (560) a measurement associated with each candidate cell in the NES-based CHO candidate cell list before the amount of time has elapsed.

[0201] Embodiment ?. The method of Embodiment 6, further comprising: responsive to determining the amount of time, determining (530) that the amount of time is less than a threshold time, wherein determining the measurement associated with each candidate cell in the NES- based CHO candidate list comprises, responsive to determining that the amount of time is less than the threshold time, initiating a measurement associated with a candidate cell in the NES- based CHO candidate list prior to receiving the indication that the network node will enter the NES mode.

[0202] Embodiment s. The method of Embodiments 6, further comprising: responsive to receiving the indication of the amount of time, determining (530) that the amount of time is greater than a threshold time, wherein determining the measurement associated with each candidate cell in the NES- based CHO candidate list comprises, responsive to determining that the amount of time is greater than the threshold time, initiating the measurement associated with each candidate cell in the NES -based CHO candidate list subsequent to receiving the indication that the network node will enter the NES mode.

[0203] Embodiment 9. The method of any of Embodiments 7-8, wherein the threshold time is based on a time that it takes for the communication device to measure and / or evaluate a NES-based CHO candidate cell.

[0204] Embodiment 10. The method of any of Embodiments 2-9, wherein initiating the NES-based CHO procedure comprises initiating the NES-based CHO procedure before the amount of time has elapsed.

[0205] Embodiment 11. The method of any of Embodiments 2-10, wherein initiating the NES-based CHO procedure comprises completing the NES-based CHO procedure before the amount of time has elapsed.

[0206] Embodiment 12. The method of any of Embodiments 2-10, further comprising: responsive to the amount of time elapsing, declaring (580) handover failure.

[0207] Embodiment 13. The method of any of Embodiments 2-10, wherein initiating the NES-based CHO procedure comprises: determining that the amount of time has elapsed; and responsive to determining that the amount of time has elapsed, performing a handover to a cell regardless of whether a condition associated with the NES-based CHO is met.

[0208] Embodiment 14. The method of any of Embodiments 1-13, wherein determining the NES-based CHO candidate cell list comprises receiving the NES-based CHO candidate cell list from the network node.

[0209] Embodiment 15. The method of any of Embodiments 1-14, wherein receiving the indication that the network node will enter the NES mode comprises receiving at least one of group common downlink control information, DCI; and media access control, MAC, control element, CE.

[0210] Embodiment 16. A method of operating a network node (300) in a wireless communications network that includes a communication device, the network node configured to provide a serving cell to the communication device and the network node being capable of entering a network energy saving, NES, mode, the method comprising: transmitting (640) an indication that the network node will enter the NES mode; and responsive to an amount of time elapsing, entering (670) the NES mode.

[0211] Embodiment 17. The method of Embodiment 16, further comprising: transmitting (610) a NES-based conditional handover, CHO, candidate cell list to the communication device;

[0212] Embodiment 18. The method of any of Embodiments 16-17, further comprising: prior to transmitting the indication that the network node will enter the NES mode, determining (620) the amount of time; and transmitting (630) an indication of the amount of time to the communication device.

[0213] Embodiment 19. The method of Embodiment 18, wherein determining the amount of time comprises determining the amount of time based on a frequency range of a candidate cell in the NES -based CHO candidate cell list.

[0214] Embodiment 20. The method of any of Embodiments 18-19, wherein determining the amount of time comprises: receiving information from a target cell in the NES-based CHO candidate dell list; and determining the amount of time based on the information.

[0215] Embodiment 21. The method of any of Embodiments 18-20, further comprising: wherein determining the amount of time comprises determining the amount of time based on a frequency range of a candidate cell in the NES-based CHO candidate cell list.

[0216] Embodiment 22. The method of any of Embodiments 18-21, wherein transmitting the indication of the amount of time to the communication device comprises transmitting a message to the network node including the indication that the network node will enter the NES mode and the indication of the amount of time.

[0217] Embodiment 23. The method of any of Embodiments 16-22, wherein transmitting the indication that the network node will enter the NES mode comprises transmitting at least one of: group common downlink control information, DCI; andmedia access control, MAC, control element, CE.

[0218] Embodiment 24. The method of any of Embodiments 16-23, wherein transmitting the indication that the network node will enter the NES mode comprises transmitting a request to the communication device for a report on an antenna muting / power reduction hypothesis, the method further comprising: receiving (650) the report from the communication device; and determining (660) that the amount of time has elapsed based on receiving the report.

[0219] Embodiment 25. The method of any of Embodiment 16-24, wherein entering the NES mode comprises switching off the serving cell.

[0220] Embodiment 26. A communication device (200), configured to perform operations comprising: determining (510) aNES-based conditional handover, CHO, candidate cell list; receiving (540) the indication that the network node will enter the NES mode; and subsequent to receiving the indication that the network node will enter the NES mode, initiating (570) aNES-based CHO procedure.

[0221] Embodiment 27. The communication device of Embodiment 26, the operations further comprising any of the operations of Embodiments 2-15.

[0222] Embodiment 28 A computer program comprising program code to be executed by processing circuitry (202) of a communication device (200), whereby execution of the program code causes the communication device to perform operations comprising: determining (510) aNES-based conditional handover, CHO, candidate cell list; receiving (540) the indication that the network node will enter the NES mode; and subsequent to receiving the indication that the network node will enter the NES mode, initiating (570) aNES-based CHO procedure.

[0223] Embodiment 29. The computer program of Embodiment 28, the operations further comprising any of the operations of Embodiments 2-15.

[0224] Embodiment 30. A computer program product comprising a non-transitory storage medium (210) including program code to be executed by processing circuitry (202) of a communication device (200), whereby execution of the program code causes the communication device to perform operations comprising: determining (510) aNES-based conditional handover, CHO, candidate cell list; receiving (540) the indication that the network node will enter the NES mode; and subsequent to receiving the indication that the network node will enter the NES mode, initiating (570) aNES-based CHO procedure.

[0225] Embodiment 31. The computer program product of Embodiment 30, the operations further comprising any of the operations of Embodiments 2-15.

[0226] Embodiment 32. A communication device (200, the communication device comprising: processing circuitry (202); and memory (210) coupled to the processing circuitry and having instructions stored therein that are executable by the processing circuitry to cause the communication device to perform operations comprising: determining (510) aNES-based conditional handover, CHO, candidate cell list; receiving (540) the indication that the network node will enter the NES mode; and subsequent to receiving the indication that the network node will enter the NES mode, initiating (570) aNES-based CHO procedure.

[0227] Embodiment 33. The communication device of Embodiment 32, the operations comprising any of the operations of Embodiments 2-15.

[0228] Embodiment 34. A non-transitory computer-readable medium having instructions stored therein that are executable by processing circuitry (202) of a communication device (200) to cause the communication device to perform operations comprising: determining (510) aNES-based conditional handover, CHO, candidate cell list; receiving (540) the indication that the network node will enter the NES mode; and subsequent to receiving the indication that the network node will enter the NES mode, initiating (570) aNES-based CHO procedure.

[0229] Embodiment 35. The non-transitory computer-readable medium of Embodiment 34, the operations further comprising any of the operations of Embodiments 2-15.

[0230] Embodiment 36. A network node (300) configured to perform operations comprising: transmitting (640) an indication that the network node will enter the NES mode; and responsive to an amount of time elapsing, entering (670) the NES mode.

[0231] Embodiment 37. The network node of Embodiment 36, the operations further comprising any of the operations of Embodiments 17-25.

[0232] Embodiment 38 A computer program comprising program code to be executed by processing circuitry (302) of a network node (300), whereby execution of the program code causes the network node to perform operations comprising: transmitting (640) an indication that the network node will enter the NES mode; and responsive to an amount of time elapsing, entering (670) the NES mode.

[0233] Embodiment 39. The computer program of Embodiment 38, the operations further comprising any of the operations of Embodiments 17-25.

[0234] Embodiment 40. A computer program product comprising a non-transitory storage medium (306) including program code to be executed by processing circuitry (302) of a network node (300), whereby execution of the program code causes the network node to perform operations comprising: transmitting (640) an indication that the network node will enter the NES mode; and responsive to an amount of time elapsing, entering (670) the NES mode.

[0235] Embodiment 41. The computer program product of Embodiment 40, the operations further comprising any of the operations of Embodiments 17-25.

[0236] Embodiment 42. A network node (300), the network node comprising: processing circuitry (302); and memory (306) coupled to the processing circuitry and having instructions stored therein that are executable by the processing circuitry to cause the network node to perform operations comprising: transmitting (640) an indication that the network node will enter the NES mode; and responsive to an amount of time elapsing, entering (670) the NES mode.

[0237] Embodiment 43. The network node of Embodiment 42, the operations further comprising any of the operations of Embodiments 17-25.

[0238] Embodiment 44. A non-transitory computer-readable medium having instructions stored therein that are executable by processing circuitry (302) of a network node (300) to cause the network node to perform operations comprising: transmitting (640) an indication that the network node will enter the NES mode; and responsive to an amount of time elapsing, entering (670) the NES mode.

[0239] Embodiment 45. The non-transitory computer-readable medium of Embodiment 38, the operations further comprising any of the operations of the Embodiments 17-25.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. If listed multiple times below, the first listing should be preferred over any subsequent listing(s). 3GPP 3rd Generation Partnership ProjectBSR Buffer Status ReportBWP Bandwidth PartCBRA Contention Based Random AccessCCCH Common Control ChannelC-RNTI Cell RNTICG Configured GrantCORESET Control Resource SetCRC Cyclic Redundancy CheckCSI Channel State InformationCSS Common Search SpaceDCI Downlink Control InformationDG Dynamic GrantDL DownlinkDL-SCH Downlink Shared channelDMRS Demodulated Reference Signal eMBB enhanced Mobile Broadband eRedCap Enhanced Reduced Capability NR DevicesIE Information ElementI-RNTI Inactive RNTILCH Logical ChannelLCID Logical Channel IDLPWA Low power wide areaLTE Long-Term EvolutionMAC Medium Access ControlMAC CE Medium Access Control - Control ElementMICO Mobile Originated Communication OnlyMIMO Multiple-Input and Multiple-Output mMTC massive Machine-Type CommunicationMsgl / 2 / 3 / 4 / 5 Message 1 / 2 / 3 / 4 / 5 of 4-step random access procedureMsgA / B Message A / B of 2-step random access procedure MTC Machine-Type Communications MT-SDT Mobile Terminated Small Data Transmission NB-IoT Narrowband Internet of ThingsNR New RadioNUL Normal UplinkNW NetworkOFDM Orthogonal Frequency-Division MultiplexingPC Power ControlPDCCH Physical Downlink Control ChannelPDSCH Physical Downlink Shared ChannelPDU Protocol Data UnitPRACH Physical Random Access ChannelPRB Physical Resource BlockPSM Power Saving ModePUCCH Physical Uplink Control ChannelPUSCH Physical Uplink Shared ChannelRA Random AccessRACH Random Access ChannelRAI Release Assistance InformationRAPID Random Access Preamble IdentifierRAR Random Access ResponseRA-RNTI Random Access RNTIRedCap Reduced Capability NR DevicesRNTI Radio Network Temporary IdentifierRRC Radio Resource ControlRSRP Received Signal Reference PowerSDT Small Data TransmissionSCS Subcarrier SpacingSI System informationSIB System information blockSRI SRS Resource IndicatorSRS Sounding Reference SignalSSB Synchronization Signal BlockSUL Supplementary UplinkTC-RNTI Temporary Cell RNTIUAI UE Assistance InformationUCI Uplink Control informationUE User equipmentUL UplinkUL-SCH Uplink Shared channelSSB Synchronization Signal BlockCD-SSB Cell-defining SSBNCD-SSB Non-cell-defining SSBNW NetworkMIB Master Information BlockGSCN Global Synchronization Channel NumberSIB System Information BlockAPPENDIX A1 IntroductionIn RAN2#121bis meeting the following agreements were reached for CHO:In RAN2#122 meeting the following agreements were reached for CHO:_In RAN2#123 meeting the following agreements were reached for CHO:Agreements1 We will support the CHO triggers for the use case of turning off the cell2 (At least for cell DTX / DRX) Time-based CHO is not to be considered in NES.3 Do not consider using an indication in SIB1 for triggering NES CHO execution conditionIn RAN2#123bis meeting the following agreements were reached for CHO:2 Remaining aspects of CHO operationIn current running RRC CR, the NES specific CHO execution condition is implemented as tag nesEvent to event configured IE CondTriggerConfig. In the procedural text, in the current CR, the intention is to allow only NES specific condition / events, legacy condition / events, or configuration where one target cell can be configured with one legacy and one NES specific event. There is FFS on whether the case where both NES and regular condition are supported for one candidate target cell. In our view also that needs to be supported as the network deployments where NES will be implemented may vary and the standards should support various ways to support these scenarios. One important scenario where this particular configuration option is useful is scenario where same candidate target cell is a so called coverage cell (on the same frequency layer most likely) and also regular mobility should be supported towards this cell.If the network deployments where NES will be implemented may vary and the standards should support various ways to support these scenarios.Proposal 1 RAN2 to support the current implementation of running RRC CR and to allow only NES specific condition / events, legacy condition / events, or configuration where one target cell can be configured with one legacy and one NES specific event.For NES, another typical scenario for using the CHO framework is for when a cell, which may be a capacity / booster cell, is about to turn off and the UEs need to be handed over to other cells. If the NES cell is deployed as capacity cell / layer, there would be coverage / overlapping cell on another carrier to which the UEs could be handed over. When CHO is used, the UEs are provided CHO configuration earlier, potentially already upon connection setup, and when the cell is about to turn off, a common DCI 2_9 including a specific bit / indicator is transmitted to trigger the handover commonly for the UEs, as per latest agreements. This is visualized in the figure below:1. w*<wtfawUH hCHOcw»i«0BThe “turn-off ’ / NES indication is sent to the UEs via a DCI transmission. The NES CHO conditions are only relevant from this point onwards so that the UE can leave the cell and e.g. handover to the coverage cell. RAN2 has concluded that UE “As a baseline, UE initiates CHO evaluation upon receiving the CHO configuration. “. This is to avoid delay for the execution of the NES CHO. While the UE cannot wait for the DCI before it initiates the CHO measurements as it does not know how long after the DCI the NW may turn off the cell, it is quite wasteful in terms of energy to let the UE measure on e.g. another carrier throughout the whole connection just in case the NW would decide to turn off the cell. It may even be so that the NW does not turn off the cell in which case the UE measurement efforts were in vain.In regular / legacy CHO the UE at all times needs to be prepared for handover upon sudden coverage deterioration at cell edge, and hence measuring already upon configuration is justified. This scenario is quite different from the NES scenario in which the NW in a controlled manner and at a known point in time decides to turn off a cell.The delay between configuring UE with NES specific CHO and receiving the DCI may vary and it may be very short or very long.When the delay is long and UE is configured to measure interfrequency with NES specific execution condition, the UE power consumption may increase unnecessarily high.When the delay is short and UE is configured to measure interfrequency with NES specific execution condition, the UE may not have had time to measure the NES specific execution condition and may end up in RLF.To inform the UE how much time there is after receiving the DCI until the source cell will turn off a conditional handover timer is defined for the NES-triggered CHO scenario. The UE is requested to execute the conditional handover within the timer. The UE then knows whether the time is long enough to delay its measurement efforts on potential target cells until after the DCI, or whether it needs to measure already before. This helps both UE and network in power saving as UE can plan the measurements better and network can switch off the cell without a long guard period to ensure UEs would not be dropped to RLF.Proposal 2 A conditional handover timer is defined for the NES-triggered CHO scenario2 Autonomous gapsIn traditional conditional handover, when UE evaluates the handover condition, UE will perform measurements as follows:• The intra- / inter-frequency measurement without gap will be measured outside gap in each SMTC or DRX.• The intra- / inter-frequency measurement with gap will be measured within gap based on Measurement Gap Repetition Period (MGRP) or DRXIf the UE receives the group common DCI to indicate the source cell is entering the NES mode soon after the NES CHO is configured, the UE shall speed up the measurement evaluation to trigger the conditional handover in some scenarios, especially if the serving cell will close soon. Thus, UE can perform the intra- / inter-frequency measurement which needs gap in autonomous gap other than waiting for the configured MG. Further, if UE is configured with interfrequency candidate target cell only with NES specific execution condition, having autonomous gaps measn network does not need to configure MG in this case.Proposal 3 In order to avoid the need for configuring MG only for NES specific CHO, and to speed up measurements, it is proposed to support autonomous measurement gaps for this.2 Handling and preventing failure casesIf the UE is performing HO or CHO and experiences HO failure due to source or target cell being or entering in NES mode, UE should inform the network about the HO failure cause. Also, when the HO is successful, UE should inform the network about NES conditions of the source / target cell.Proposal 4 If the UE is performing HO or CHO, UE should inform the network about the HO trigger cause, i.e. if the HO was triggered because the serving cell wanted to enter NES mode, either in HO failure or HO success reports.As the key thing is to prevent network creating coverage holes, other solutions can be considered as well. Main issue is that the network should be aware if coverage hole is created by cell entering to NES mode. Also, the level of performance degradation would be beneficial to be known at the network side.Main issue is that the network should be aware if coverage hole is created and the level of performance degradation created by cell entering to NES mode.Proposal 5 RAN2 to discuss if UE feedback would be beneficial for the cell to determine when to turn off the cell or to configure cell DTX / DRX.2 Stage-2 description for CHOA TP for 38.300 is provided in the Annex to capture the basic CHO functionality for NES.Proposal 6 RAN2 to agree on the TP provided for 38.300.ConclusionIn the previous sections we made the following observations:Observation 1 If the network deployments where NES will be implemented may vary and the standards should support various wavs to support these scenarios.Observation 2 The delay between configuring UE with NES specific CHO and receiving the DCI mav vary and it may be very short or very long.Observation 3 When the delay is long and UE is configured to measure interfrequencv with NES specific execution condition, the UE power consumption mav increase unnecessarily high.Observation 4 When the delay is short and UE is configured to measure interfrequencv with NES specific execution condition, the UE may not have had time to measure the NES specific execution condition and may end up in RLF.Observation 5 Main issue is that the network should be aware if coverage hole is created and the level of performance degradation created by cell entering to NES mode.Based on the discussion in the previous sections we propose the following:Proposal 1 RAN2 to support the current implementation of running RRC CR and to allow only NES specific condition / events, legacy condition / events, or configuration where one target cell can be configured with one legacy and one NES specific event.Proposal 2 A conditional handover timer is defined for the NES-triggered CHO scenarioProposal 3 In order to avoid the need for configuring MG only for NES specific CHO, and to speed up measurements, it is proposed to support autonomous measurement gaps for this.Proposal 4 If the UE is performing HO or CHO, UE should inform the network about the HO trigger cause, i.e. if the HO was triggered because the serving cell wanted to enter NES mode, either in HO failure or HO success reports.Proposal 5 RAN2 to discuss if UE feedback would be beneficial for the cell to determine when to turn off the cell or to configure cell DTX / DRX.Proposal 6 RAN2 to agree on the TP provided for 38.300.ReferencesTR 38.864, Study on network energy savings for NRRP-223540, New WID: Network energy savings for NR3 TP to 38.30015.4.2.x2 Conditional HandoverThe same principle as described in 9.2.3.4 applies to conditional handover in case the source cell is using a network energy saving solution, unless hereunder specified. In this case, the following additional triggering conditions are supported, upon which UE may execute CHO to a candidate cell, as defined in TS 38.331 [x] :Proposal 7 - The UE may be notified via DCI that a source cell is activating cell DTX / DRX or that a cell is turning off.

Claims

CLAIMS1. A method of operating a communication device in a wireless communications network that includes a network node configured to provide a serving cell, the network node being capable of entering a network energy saving, NES, mode, the method comprising: receiving (710) a NES-based conditional handover, CHO, candidate cell list from the network node; receiving (730) an indication that the network node will enter the NES mode; and subsequent to receiving the indication that the network node will enter the NES mode, initiating (740) a NES-based CHO procedure; wherein the method further comprises: receiving (720) an indication of an amount of time between the indication that the network node will enter the NES mode being received and a time that the network node will enter the NES mode from the network node; and wherein initiating (740) the NES-based CHO procedure comprises initiating the NES-based CHO procedure before the amount of time has elapsed.

2. The method of Claim 1, wherein receiving (730) the indication that the network node will enter the NES mode comprises receiving a downlink control information, DCI, comprising the indication that the network node will enter the NES mode.

3. The method of Claim 2, wherein the DCI is a group common DCI.

4. The method of any of Claims 1 to 3, wherein initiating (740) the NES-based CHO procedure comprises completing the NES-based CHO procedure before the amount of time has elapsed.

5. The method of any of Claims 1 to 4, further comprising: performing (745) a measurement associated with each candidate cell in the NES-based CHO candidate cell list before the amount of time has elapsed.

6. The method of Claim 5, wherein performing (745) the measurement associated with each candidate cell in the NES-based CHO candidate cell list before the amount of time has elapsed comprises: when the amount of time is greater than a threshold time, initiating the measurement associated with each candidate cell in the NES-based CHO candidate cell list subsequent to receiving the indication that the network node will enter the NES mode.

7. The method of Claim 5 or 6, wherein performing (745) the measurement associated with each candidate cell in the NES-based CHO candidate cell list before the amount of time has elapsed comprises: when the amount of time is less than a threshold time, initiating the measurement associated with each candidate cell in the NES-based CHO candidate cell list prior to receiving the indication that the network node will enter the NES mode.

8. The method of any of Claims 1 to 7, wherein the indication of the amount of time is received prior to the indication that the network node will enter the NES mode.

9. The method of any of Claims 1 to 8, wherein the indication of the amount of time is received in a Radio Resource Control, RRC, message.

10. The method of Claim 9, wherein the indication of the amount of time is received in Information Element, IE, CondTriggerConfig.

11. The method of any of Claims 1 to 5, wherein the indication of the amount of time is received in the DCI comprising the indication that the network node will enter the NES mode.

12. The method of any of Claims 1 to 11, wherein the indication of the amount of time indicates an amount of time from a plurality of candidate amounts of time.

13. The method of any of Claims 1 to 12, wherein the amount of time is an integer of time with a unit of a milli-second.

14. A method of operating a network node in a wireless communications network that includes a communication device, the network node configured to provide a serving cell to the communication device and the network node being capable of entering a network energy saving, NES, mode, the method comprising: transmitting (800) a NES-based conditional handover, CHO, candidate cell list to the communication device; and transmitting (840) an indication that the network node will enter the NES mode to the communication device; wherein the method further comprises: transmitting (820), to the wireless communication device, an indication of an amount oftime between the indication that the network node will enter the NES mode being received by the communication device and a time that the network node will enter the NES mode; and after the amount of time elapsing, entering (860) the NES mode.

15. The method of Claim 14, further comprising: prior to transmitting the indication that the network node will enter the NES mode, transmitting (630) the indication of the amount of time to the communication device.

16. The method of Claim 14 or 15, wherein entering (860) the NES mode comprises switching off the serving cell.

17. A communication device (200), configured to perform operations comprising: receiving aNES-based conditional handover, CHO, candidate cell list from the network node; receiving an indication that the network node will enter the NES mode; and subsequent to receiving the indication that the network node will enter the NES mode, initiating aNES-based CHO procedure; wherein the communication device is further configured to perform an operation comprising: receiving an indication of an amount of time between the indication that the network node will enter the NES mode being received and a time that the network node will enter the NES mode from the network node; and wherein initiating the NES-based CHO procedure comprises initiating the NES-based CHO procedure before the amount of time has elapsed.

18. The communication device of Claim 17, the operations further comprising any of the operations of Claims 2-13.

19. A network node (300) configured to perform operations comprising: transmitting a NES-based conditional handover, CHO, candidate cell list to the communication device; and transmitting an indication that the network node will enter the NES mode to the communication device; wherein the network node is further configured to perform operations comprising: transmitting, to the wireless communication device, an indication of an amount oftime between the indication that the network node will enter the NES mode being received by the communication device and a time that the network node will enter the NES mode; and after the amount of time elapsing, entering the NES mode.

20. The network node of Claim 19, the operations further comprising any of the operations of Claims 14-16.

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