Cell dtx / drx state upon scell configuration

Abstract

A method of facilitating intermittent channel monitoring performed by a network node is provided. The method includes sending, towards a user equipment (UE), a first indication that activates a serving cell for the UE. The method includes, sending a second indication, towards the UE, indicating a cell discontinuous transmission (DTX) and / or discontinuous reception (DRX) state (activated or deactivated) for the serving cell.

Description

CELL DTX / DRX STATE UPON SCELL CONFIGURATIONTechnical Field

[0001] The present disclosure relates to cell discontinuous transmission (DTX) and / or discontinuous reception (DRX) state upon, e.g., Secondary cell (Scell) configuration.BackgroundCell DTX / DRX

[0002] To facilitate reducing gNodeB (gNB) downlink transmission / uplink reception activity time, a user equipment (UE) may be configured with a periodic cell DTX / DRX pattern (i.e., active and non-active periods). The pattern configuration for cell DTX / DRX is common for UEs configured with this feature in the cell. The cell DTX and cell DRX patterns can be configured and activated separately. When cell DTX is configured and activated for the concerned cell, the UE does not monitor the Physical Downlink Control Channel (PDCCH) in selected cases or Semi-Persistent Scheduling (SPS) occasions during cell DTX non-active duration. When cell DRX is configured and activated for the concerned cell, the UE does not transmit on configured grant (CG) resources or transmit a scheduling request (SR) during cell DRX non-active duration. This feature is only applicable to UEs in RRC CONNECTED state and it does not impact Random Access procedure, Synchronization Signal Block (SSB) transmission, paging, and system information broadcasting. Cell DTX / DRX can be activated / deactivated by Radio Resource Control (RRC) signaling or LI group common signaling, i.e., a Downlink Control Information (DCI) is broadcasted in a cell to indicate activation / deactivation of cell DTX / DRX for all UEs that have such cell configured as a serving cell.Carrier Aggregation

[0003] Carrier Aggregation is a feature in 5G New Radio (NR) which allows the UE to aggregate more bandwidth by simultaneously using multiple cells. Any cell which the UE is configured to use is considered a “serving” cell for the UE.

[0004] One of the serving cells is considered more important that the other cells, and is referred to as the Primary Cell (PCell). Any other cells are referred to as Secondary Cells (SCells). SCells can be deactivated, which, among other things, makes the UE stop monitoring PDCCH on that serving cell. This is supposed to at least help the UE save power.

[0005] SCells are activated and deactivated using Medium Access Control (MAC) Control Elements (CEs) sent by the network to the UE. The activation state is UE- specific, meaning that a cell may be activated for a first UE (UE A), while the same cell is deactivated for a second UE (UE B).

[0006] An activated SCell can be using a dormant bandwidth part (BWP) or a nondormant BWP. When using a dormant BWP, the UE also does not monitor PDCCH on that serving cell (as in SCell deactivated state), but the UE still provides channel state information (CSI) reports and a faster transition to non-dormant BWP is expected when compared to the transition of SCell deactivated state to an SCell activated state with a non-dormant BWP. FIG. 1 summarizes the SCell states and relation with dormant BWP. As shown in FIG. 1, an SCell may switch between an activated state 102 and a deactivated state 104, e.g., via MAC CE messages. In activated state 104, the SCell may also switch between a dormant BWP 106 and non-dormant BWP 108, e.g., via DCI messages.

[0007] It should further be noted that the cell used by one UE as PCell may be an SCell for another UE.

[0008] There currently exist certain challenge(s). When an SCell is deactivated for a UE (or the SCell is activated but with a dormant BWP), or a primary cell of a secondary cell group (SGC), referred to as a PSCell, is deactivated that UE will not monitor PDCCH. This means that the UE will not hear potential DCIs which indicate when cell DTX / DRX becomes enabled / disabled. Similarly, when a UE stays in INACTIVE mode of the cell, the UE will also not know the cell’s cell DTX / DRX status.Summary

[0009] Embodiments of the present disclosure provide for synchronization between the UE and the network with regards to the cell DRX / DTX states for a cell when that cell is activated for the UE.

[0010] An aspect of the present disclosure provides a method of facilitating intermittent channel monitoring performed by a network node, the method comprising:• sending, towards a user equipment (UE), a first indication that activates a serving cell for the UE; and• sending a second indication, towards the UE, indicating a cell discontinuous transmission (DTX) and / or discontinuous reception (DRX) state (activated or deactivated) for the serving cell.

[0011] In some embodiments, the serving cell comprises a secondary cell (Scell).

[0012] In some embodiments, the second indication is broadcasted toward multiple user equipments including the UE.

[0013] In some embodiments, the second indication is comprised in a Downlink Control Indicator (DCI).

[0014] In some embodiments, the second indication is sent in a message specific to the UE.

[0015] In some embodiments, the second indication is comprised in one of a Medium Access Control (MAC) message and a Radio Resource Control (RRC) message.

[0016] In some embodiments, there is a delay T between sending the second indication after the first indication has been sent, and T is configured to allow the UE time to activate the serving cell.

[0017] In some embodiments, T is (or is about) 24 milliseconds.

[0018] In some embodiments, T is further configured to allow other user equipments time to activate the serving cell.

[0019] In some embodiments, the method further comprises, prior to sending the second indication, determining that the cell DTX and / or DRX state for the serving cell has changed during a time when the serving cell was deactivated for the UE.

[0020] In some embodiments, the second indication comprises separate indications for one or more cell DTX configurations and / or one or more cell DRX configurations.

[0021] Another aspect of the present disclosure provides a method of facilitating intermittent channel monitoring performed by a user equipment (UE), the method comprising:• activating a serving cell for the UE;• as a result of activating the serving cell for the UE, determining a cell discontinuous transmission (DTX) and / or discontinuous reception (DRX) state for the serving cell based on a default state.

[0022] In some embodiments, the default state is an activated state.

[0023] In some embodiments, the method further comprises receiving an indication from a network node to apply the default state.

[0024] In some embodiments, the indication is comprised in one of a Radio Resource Control (RRC) message and a Medium Access Control (MAC) message.

[0025] In some embodiments, the default state is set based on one of: an initial DTX / DRX state of the serving cell, and a preconfigured value in the UE.

[0026] A further aspect of the present disclosure provides a method of facilitating intermittent channel monitoring performed by a Radio Link Control (RLC) node, the method comprising:• receiving a cell discontinuous transmission (DTX) and / or discontinuous reception (DRX) configuration from a first serving cell in a cell group; and• applying the cell DTX and / or DRX configuration for each cell in the cell group.

[0027] In some embodiments, the method further comprises receiving, from a second serving cell, an indication of which cell controls the cell DTX and / or DRX configuration for a cell group, wherein the indication indicates the first serving cell.

[0028] In some embodiments, the indication comprises a logical channel id (LCID).

[0029] A further aspect of the present disclosure provides a method of facilitating intermittent channel monitoring performed by a gNodeB Distributed Unit (gNB-DU), the method comprising:• determining that a cell discontinuous transmission (DTX) and / or discontinuous reception (DRX) status has changed; and• as a result of determining that the cell DTX and / or DRX status has changed, sending towards a gNodeB Centralized Unit (gNB-CU) an indication of the cell DTX and / or DRX status having changed.

[0030] A further aspect of the present disclosure provides a method of facilitating intermittent channel monitoring performed by a user equipment (UE), the method comprising:• receiving an indication from a reference cell; and• determining a serving cell discontinuous transmission (DTX) and / or discontinuous reception (DRX) status based on the indication.

[0031] In some embodiments, the indication includes an index for the serving cell and one or more of cell DTX / DRX state and cell DTX / DRX patterns.

[0032] In some embodiments, the indication is comprised in one of a Downlink Control Indicator (DCI) message, a Medium Access Control (MAC) Control Element (CE), and a Radio Resource Control (RRC) message.

[0033] In some embodiments, the reference cell is preconfigured.

[0034] In some embodiments, the reference cell is provided to the UE by a network node.

[0035] A further aspect of the present disclosure provides a network node comprising:• processing circuitry (802); and• a memory, the memory containing instructions (844) executable by the processing circuitry (802), whereby when executed the processing circuitry (802) is configured to:• send, towards a user equipment (UE), a first indication that activates a serving cell for the UE; and• send a second indication, towards the UE, indicating a cell discontinuous transmission (DTX) and / or discontinuous reception (DRX) state (activated or deactivated) for the serving cell.

[0036] A further aspect of the present disclosure provides a user equipment (UE) comprising:• processing circuitry (802); and• a memory, the memory containing instructions (844) executable by the processing circuitry (802), whereby when executed the processing circuitry (802) is configured to:• activate a serving cell for the UE;• as a result of activating the serving cell for the UE, determine a cell discontinuous transmission (DTX) and / or discontinuous reception (DRX) state for the serving cell based on a default state.

[0037] A further aspect of the present disclosure provides a Radio Link Control (RLC) node comprising:• processing circuitry (802); and• a memory, the memory containing instructions (844) executable by the processing circuitry (802), whereby when executed the processing circuitry (802) is configured to:• receive a cell discontinuous transmission (DTX) and / or discontinuous reception (DRX) configuration from a first serving cell in a cell group; and• apply the cell DTX and / or DRX configuration for each cell in the cell group.

[0038] A further aspect of the present disclosure provides a gNodeB Distributed Unit (gNB-DU) comprising:• processing circuitry (802); and• a memory, the memory containing instructions (844) executable by the processing circuitry (802), whereby when executed the processing circuitry (802) is configured to:• determine that a cell discontinuous transmission (DTX) and / or discontinuous reception (DRX) status has changed; and• as a result of determining that the cell DTX and / or DRX status has changed, send towards a gNodeB Centralized Unit (gNB-CU) an indication of the cell DTX and / or DRX status having changed.

[0039] A further aspect of the present disclosure provides a user equipment (UE) comprising:• processing circuitry (802); and• a memory, the memory containing instructions (844) executable by the processing circuitry (802), whereby when executed the processing circuitry (802) is configured to:• receive an indication from a reference cell; and• determine a serving cell discontinuous transmission (DTX) and / or discontinuous reception (DRX) status based on the indication.

[0040] Embodiments of a base station, communication system, and a method in a communication system are also disclosed.Brief Description of the Drawings

[0041] The accompanying drawing figures incorporated in and forming a part of this specification illustrate several aspects of the disclosure, and together with the description serve to explain principles of the disclosure.

[0042] FIG. 1 illustrates activated and deactivated states of an SCell.

[0043] FIG. 2 illustrates a system according to an embodiment.

[0044] FIG. 3 illustrates a flowchart according to an embodiment.

[0045] FIG. 4 illustrates a flowchart according to an embodiment.

[0046] FIG. 5 illustrates a flowchart according to an embodiment.

[0047] FIG. 6 illustrates a flowchart according to an embodiment.

[0048] FIG. 7 illustrates a flowchart according to an embodiment.

[0049] FIG. 8 is a block diagram of an apparatus according to an embodiment.Detailed Description

[0050] The embodiments set forth below represent information to enable those skilled in the art to practice the embodiments and illustrate the best mode of practicing the embodiments. Upon reading the following description in light of the accompanying drawing figures, those skilled in the art will understand the concepts of the disclosure and will recognize applications of these concepts not particularly addressed herein. It should be understood that these concepts and applications fall within the scope of the disclosure.

[0051] At least some of the following abbreviations and terms may be used in this disclosure.• 2D Two Dimensional• 3 GPP Third Generation Partnership Project• 5G Fifth Generation• AAS Antenna Array SystemAoA Angle of ArrivalAoD Angle of DepartureASIC Application Specific Integrated Circuit BF BeamformingBLER Block Error RateBW BeamwidthCPU Central Processing UnitCSI Channel State Information dB DecibelDCI Downlink Control InformationDFT Discrete Fourier TransformDSP Digital Signal Processor eNB Enhanced or Evolved Node BFIR Finite Impulse ResponseFPGA Field Programmable Gate Array gNB New Radio Base StationICC Information Carrying CapacityIIR Infinite Impulse ResponseLTE Long Term EvolutionMIMO Multiple Input Multiple OutputMME Mobility Management EntityMMSE Minimum Mean Square ErrorMTC Machine Type CommunicationNR New RadioOTT Over-the-TopPBCH Physical Broadcast ChannelPDCCH Physical Downlink Control ChannelPDSCH Physical Downlink Shared ChannelP-GW Packet Data Network Gateway• RAM Random Access Memory• ROM Read Only Memory• RRC Radio Resource Control• RRH Remote Radio Head• SCEF Service Capability Exposure Function• SINR Signal to Interference plus Noise Ratio• TBS Transmission Block Size• UE User Equipment• ULA Uniform Linear Array• URA Uniform Rectangular Array

[0052] Radio Node: As used herein, a “radio node” is either a radio access node or a wireless device.

[0053] Radio Access Node: As used herein, a “radio access node” or “radio network node” is any node in a radio access network of a cellular communications network that operates to wirelessly transmit and / or receive signals. Some examples of a radio access node include, but are not limited to, a base station (e.g., a New Radio (NR) base station (gNB) in a Third Generation Partnership Project (3GPP) Fifth Generation (5G) NR network or an enhanced or evolved Node B (eNB) in a 3GPP Long Term Evolution (LTE) network), a high-power or macro base station, a low-power base station (e.g., a micro base station, a pico base station, a home eNB, or the like), and a relay node.

[0054] Core Network Node: As used herein, a “core network node” is any type of node in a core network. Some examples of a core network node include, e.g., a Mobility Management Entity (MME), a Packet Data Network Gateway (P-GW), a Service Capability Exposure Function (SCEF), or the like.

[0055] Wireless Device: As used herein, a “wireless device” is any type of device that has access to (i.e., is served by) a cellular communications network by wirelessly transmitting (and / or receiving) signals to (and / or from) a radio access node. Someexamples of a wireless device include, but are not limited to, a User Equipment device (UE) in a 3GPP network and a Machine Type Communication (MTC) device.

[0056] Network Node: As used herein, a “network node” is any node that is either part of the radio access network or the core network of a cellular communications network / system.

[0057] Cell: As used herein, a “cell” is a combination of radio resources (such as, for example, antenna port allocation, time and frequency) that a wireless device may use to exchange radio signals with a radio access node, which may be referred to as a host node or a serving node of the cell. However, it is important to note that beams may be used instead of cells, particularly with respect to 5G NR. As such, it should be appreciated that the techniques described herein are equally applicable to both cells and beams.

[0058] Note that references in this disclosure to various technical standards (such as 3GPP TS 38.211 V15.1.0 (2018-03) and 3GPP TS 38.214 V15.1.0 (2018-03), for example) should be understood to refer to the specific version(s) of such standard(s) that is(were) current at the time the present application was filed, and may also refer to applicable counterparts and successors of such versions.

[0059] The description herein focuses on a 3GPP cellular communications system and, as such, 3 GPP terminology or terminology similar to 3 GPP terminology is oftentimes used. However, the concepts disclosed herein are not limited to a 3 GPP system.

[0060] Embodiments herein are described in the context of SCell activation / deactivation. However, embodiments can apply to other circumstances, such as features which allow the UE to intermittently monitor a channel on which the network indicates the state of cell DRX and cell DTX features, such as dormant BWP.

[0061] Embodiments can also serve the PSCell activation / deactivation in dual connectivity (DC) mode.

[0062] Embodiments can also apply to the UE in INACTIVE mode.

[0063] For brevity, the notation “cell DRX / DTX” will be used herein. This should not be interpreted as meaning cell DRX and cell DTX necessarily is the same feature or as the state of cell DRX and cell DTX always is the same. The embodiments herein can be applied independently to one or both of cell DTX and cell DRX. That is, embodiments may be applied to only cell DTX, to only cell DRX, or to both cell DTX and cell DRX. For example, the UE may perform certain actions described in the embodiments disclosed herein to both cell DRX and cell DTX.

[0064] Cell DRX / DTX is “enabled” will be used to describe the situation when a cell DTX / DRX configuration is currently in use by the network. If not currently in use, it will herein be referred to as cell DRX / DTX is “disabled”.Embodiment Set 1

[0065] In these embodiments, the network resends DRX / DTX state indications at SCell activation. That is, the network may trigger a DCI to indicate the current cell DRX / DTX state, i.e. if it is enabled or disabled.

[0066] In one embodiment, a network node sends a first indication that activates a serving cell for the UE (e.g. an SCell). The network node then sends a second indication to (all, or a subset of) UEs in the cell which indicates whether cell DTX / DRX is activated or deactivated. This second indication may be indicated in a DCI used for indicating the cell DTX / DRX state.

[0067] Consider the example where there are two UEs using a cell (referred to as cell 1) as a serving cell (the two UEs referred to as UE A and UE B). For UE A, the cell 1 is activated and hence UE A will monitor for DCIs indicating whether the cell DTX / DRX feature becomes enabled or disabled, and hence UE A will be in-sync with the network. However, in this example, cell 1 is an SCell for UE B and it is currently deactivated for UE B, and while the cell is deactivated for UE B, UE B will not monitor PDCCH and hence not be able to receive indications about if cell DRX / DTX becomes enabled or disabled. With this embodiment, when the network activates cell 1 for UE B, it would send a DCI in the cell which indicates the current state of the cell DTX / DRXconfigurations. This may then mean that if the cell DRX / DTX was enabled, the network would indicate again that cell DRX / DTX is enabled so that UE B would also know this.

[0068] Note, there is a difference between this embodiment and the later embodiments in that the DCI is used here to enable / disable cell DTX / DRX, while some other embodiments can rely on other rules that would not require DCI.

[0069] In some embodiments, there may be coordination between nodes so that all nodes are aware of users that have a cell configured and currently in deactivated state.

[0070] The network may delay sending the DCI (i.e., the second indication) for a time T after the network has instructed the UE to activate the cell (i.e., the first indication). In a first approach, the network delays the DCI for a time T1 long enough to ensure that the UE has completed all procedures for the cell activation which are needed to allow the UE to monitor PDCCH, and hence allow the UE to listen for the DCI. The UE requirements on performing SCell activation is 24 milliseconds in certain situations and hence the network may wait with sending the DCI at least 24 milliseconds after the cell activation command has been sent. In some other situations the delay to activate an SCell is different and the network may select the time T1 depending on how long time it is expected before the UE can listen for the DCI.

[0071] In another approach, the network waits a time T2 after the cell has been activated where T2 is longer than Tl. The purpose of this may be that if there are more than one UE which the network should activate the cell for, the network can avoid having to send too frequent DCIs and instead the NW can wait until the cell has been activated for more than one UEs and then send a DCI with the purpose to get all of those UEs in-sync with the actual cell DTX / DRX state of the cell.

[0072] In some embodiments, if the cell DTX / DRX state has not changed during the time the cell was deactivated for UE B, the network refrains from repeating the DCI. The advantage of this approach is that it refrains from sending unnecessary DCIs. In some embodiments, as an alternative, if the cell DTX / DRX state is the same when the cell becomes activated for UE B as it was when the cell became deactivated for UEB. This allows the network to enable and disable cell DRX / DTX freely during the time when the cell is deactivated for UE B, and the network would only need to send the DCI if cell DTX / DRX state is different from the time the cell became deactivated for UE B to the time when it became activated again. Consider the example that the cell DTX / DRX was disabled when the cell became deactivated for UE B. The network can enable and disable cell DTX / DRX many times freely. However, if at a time the cell becomes activated for UE B, the network would send the DCI to indicate the cell DRX / DTX state if the current state is enabled. Both these alternatives have the benefit that the network does not send the DCI unless necessary.Embodiment Set 2

[0073] In these embodiments, the UE applies a default state for cell DTX / DRX upon configuration. The UE considers the cell DRX / DTX state to be a default state upon SCell activation; for example, it may consider it enabled.

[0074] In some embodiments, a UE will consider the cell DTX / DRX state to be in a default state upon activation of a cell. For example, if cell DTX / DRX is disabled for an SCell for the UE and the SCell becomes deactivated for the UE, when the cell later becomes activated again the UE would consider the cell DTX / DRX enabled even if the last instruction the UE got from the network was that cell DTX / DRX was disabled.

[0075] In some embodiments, whether the UE shall apply such default state may be indicated by the network, for example, in an RRC or MAC message. Since a field can be used for cell DTX / DRX initial state upon configuration of cell DTX / DRX, this field can be reused as a default state to be applied by the UE once the SCell is activated. Another approach is that the network configures, e.g. with RRC, whether the UE shall consider the default state is to be “enabled” or “disabled”. This can be configured per cell DTX / DRX configuration. Another approach is that the default state is specified in a specification, e.g. specified to be enabled. Another approach is that it is preconfigured in the UE, e.g. configured on a SIM-card or by a core network node.

[0076] It may be that if the cell DRX (for example) is enabled, but a UE activates that cell and considers the cell DRX disabled, the UE may perform transmissions which are not expected by the network. Such unexpected transmissions may cause interference to the network and hence this embodiment may ensure that the UE will not perform any unexpected transmissions and interference can be avoided.Embodiment Set 3

[0077] In these embodiments, the network indicates together with the activation command the cell DRX / DTX state. The network may indicate (with UE-dedicated signaling) the cell DRX / DTX state the UE shall apply when the network indicates that the UE shall activate the cell.

[0078] In some embodiments, the network sends a first indication to the UE to indicate that the UE shall activate an SCell and the network also sends a second indication indicating the cell DRX / DTX state. The first indication may be sent in, for example, an SCell Activation / deactivation MAC CE or SCell addition / release RRC signaling. The second indication may be indicated in a UE-specific message (i.e. a message sent only to / for this UE). For example, the second indication may be sent in a MAC message (e.g. a MAC control element (MAC CE) in a DCI, or an RRC message. In some embodiments, the second indication may be included in the same message as the first indication. For example, the second indicaiton may be indicated in the same MAC CE / RRC reconfiguration which is activating the cell (i.e. in an SCell Activation / Deactivation MAC CE or a direct SCell activation RRC), which may require to introduce a new version of the SCell Activation / Deactivation MAC CE which carries indications of the current state.

[0079] There may be one indication for cell DTX and another indication for cell DRX. And further, since it might be the case that there are multiple cell DTX configurations and multiple cell DRX configurations: there may be one indication per cell DTX configuration. In Rel-18, RAN2 has agreed that there will be at most two cell DRX configurations and at most two cell DTX configurations and hence 4 bits can be sufficient to address two cell DTX and two cell DRX configurations. Note that one cellDRX / DTX configuration can apply to multiple cells. The signaling can also be extended in the future to support more cell DTX / DRX configurations. These indications may be bits which, if set to a first value, indicates that the UE shall consider the associated cell DRX / DTX configuration enabled and, if set to a second value, indicates that the UE shall consider the associated cell DRX / DTX configuration disabled.

[0080] This has the benefit over Embodiment Set 1 in that the network does not need to send the current cell DRX / DTX state to all (or a subset of) UEs using a cell just because the network activates the cell for one of those UEs.

[0081] In absence of the indications described herein, the UE may consider the cell DRX / DTX configurations to have a default state, e.g. as described in Embodiment Set 2.

[0082] When a UE from INACTIVE mode enters CONNECTED mode, the network can indicate the cell’s Cell DTX status together with the RRC resume signaling.Embodiment Set 4

[0083] In these embodiments, it may be specified that a reference cell will provide the Cell DTX / DRX configuration pattern. In the scenario when more than 2 Radio Link Controls (RLCs) are deployed (in Packet Data Convergence Protocol (PDCP) duplication or Carrier Aggregation (CA)), the Cell DTX / DRX for the involved cells need to be coordinated. It could be specified which cell(s) determines and provides the Cell DTX / DRX configuration pattern, and which cell(s) follows which determining cell(s).

[0084] In this disclosure, RLC is used to indicate the cell used by the UE. Control in the below context indicates the Cell DTX / DRX configuration of the Cell is used for its own cell and might be used by other cells.

[0085] In some embodiments, a standard, such as 3GPP TS 37.340, could specify that the PCell and the PsCell will provide the Cell DTX / DRX configuration pattern. The Scells in the Master Cell Group will use the same Cell DTX / DRX configuration as PCell, and the SCells in the Secondary Cell Group will use the same Cell DTX / DRXconfiguration as PsCell. This way the coordination over Xn can be avoided. In some embodiments, as an alternative, it could be decided that all the SCells follow the PCell, or PsCell Configuration.Embodiment Set 5

[0086] In these embodiments, it may be indicated which RLC path will decide on the Cell DTX / DRX configuration pattern. The embodiments of Embodiment Set 4 may have a limitation when not all the cells are configured with Cell DTX / DRX. A flexible approach is to indicate to a RLC entity, e.g., via LCID, which path will provide the Cell DTX / DRX configuration and should be followed. The Cell DTX / DRX configuration or an index (if predefined) may be provided as well.

[0087] In the below example, it is assumed that the RLC controls the Cell DTX / DRX configuration should be active. A reconfiguration of the RLC is needed when the early “controlling RLC” goes to inactive. In the table below, rows labeled with “[Addition]” are proposed changes to the specification.Beginning of excerpt from 3 GPP TS 38.4239.2.3.111 RLC Duplication InformationThis IE indicates the RLC duplication configuration in case that the indicated DRB is configured with more than two RLC entities as specified in TS 38.331

[0010] ,End of excerpt from 3 GPP TS 38.423

[0088] It may be defined that despite the Cell activation status for the UE, its Cell DTX / DRX configuration is used by other active cells. In this case, no condition needs to be defined in the specification. Embodiment Set 6

[0089] In these embodiments, the Cell DTX / DRX activation / deactivation status are transferred among the network entities. If Cell DTX / DRX activation status is changed via LI in the gNB Distributed Unit (gNB-DU), the gNB-DU may indicate it to the gNB Centralized Unit (gNB-CU), on a cell level (if the activation update is for all the UEs in the same Cell), or on a UE / UE group level (if the activation update is for a UE or a UE group).

[0090] The SCells may indicate this to SpCell where the RRC signaling is sent to the UE.Embodiment Set 7

[0091] In these embodiments, the SCell Cell DTX / DRX state may be indicated by reference cell. In some embodiments, the network can indicate the SCells’ Cell DTX / DRX status in a reference cell. The reference cell can provide the indication.

[0092] The indication can include the Scell index and the Cell DTX / DRX status and / or patterns. When the UE receives the indication, the UE will know whether the status of the SCells will change or not. If no cell DTX / DRX pattern is indicated or only indicates the Cell DTX / DRX ON, the default cell DTX / DRX will be applied. The default cell DTX / DRX pattern can be defined as the first / least index cell DTX / DRX pattern in the pattern sets.

[0093] The indication can be applied by DCI or MAC CE, or RRC signaling. The indication can be a list to include all cell’s Cell DTX / DRX status or only include one or more specific cell’s Cell DTX / DRX status.

[0094] In some embodiments, the reference cell can be pre-defined. For example, PCell can be the reference cell for the SCells to-be-activated in master cell group (MCG) and also deactivated PSCell, and PSCell can be the reference cell for the SCells to-be-activated in secondary cell group (SCG).

[0095] In another embodiment, the network can indicate the reference cell to the UE.

[0096] In another embodiment, the anchor cell defined for Network Energy Saving (NES) mode can be the reference cell. The UE can receive the cell DTX / DRX status from the anchor cell. The anchor cell can be any cell pre-defined or configured by the network.

[0097] FIG. 2 illustrates a system according to an embodiment. As shown, a UE 202 may be in a network and communicatively coupled with one or more serving cells204, as well as one or more additional network nodes 206. This diagram is illustrative. Other lines of communication may exist. For example, the additional network nodes 206 may also be communicatively coupled to the serving cells 204.

[0098] FIG. 3 is a flowchart illustrating a process 300 for facilitating intermittent channel monitoring, according to an embodiment, performed by a network node. Process 300 may begin in step s302.

[0099] Step s302 comprises sending, towards a user equipment (UE), a first indication that activates a serving cell for the UE.

[0100] Step s302 comprises, sending a second indication, towards the UE, indicating a cell discontinuous transmission (DTX) and / or discontinuous reception (DRX) state (activated or deactivated) for the serving cell.

[0101] In some embodiments, the serving cell comprises a secondary cell (Scell). In some embodiments, the second indication is broadcasted toward multiple user equipments including the UE. In some embodiments, the second indication is comprised in a Downlink Control Indicator (DCI). In some embodiments, the second indication is sent in a message specific to the UE. In some embodiments, the second indication is comprised in one of a Medium Access Control (MAC) message and a Radio Resource Control (RRC) message. In some embodiments, there is a delay T between sending the second indication after the first indication has been sent, and T is configured to allow the UE time to activate the serving cell. In some embodiments, T is (or is about) 24 milliseconds. In some embodiments, T is further configured to allow other user equipments time to activate the serving cell. In some embodiments, the method further includes, prior to sending the second indication, determining that the cell DTX and / or DRX state for the serving cell has changed during a time when the serving cell was deactivated for the UE. In some embodiments, the second indication comprises separate indications for one or more cell DTX configurations and / or one or more cell DRX configurations.

[0102] FIG. 4 is a flowchart illustrating a process 400 for facilitating intermittent channel monitoring, according to an embodiment, performed by a user equipment (UE). Process 400 may begin in step s402.

[0103] Step s402 comprises activating a serving cell for the UE.

[0104] Step s404 comprises, as a result of activating the serving cell for the UE, determining a cell discontinuous transmission (DTX) and / or discontinuous reception (DRX) state for the serving cell based on a default state.

[0105] In some embodiments, the default state is an activated state. In some embodiments, the method further includes receiving an indication from a network node to apply the default state. In some embodiments, the indication is comprised in one of a Radio Resource Control (RRC) message and a Medium Access Control (MAC) message. In some embodiments, the default state is set based on one of: an initial DTX / DRX state of the serving cell, and a preconfigured value in the UE.

[0106] FIG. 5 is a flowchart illustrating a process 500 for facilitating intermittent channel monitoring, according to an embodiment, performed by a Radio Link Control (RLC) node. Process 500 may begin in step s502.

[0107] Step s502 comprises receiving a cell discontinuous transmission (DTX) and / or discontinuous reception (DRX) configuration from a first serving cell in a cell group.

[0108] Step s504 comprises applying the cell DTX and / or DRX configuration for each cell in the cell group.

[0109] In some embodiments, the method further includes receiving, from a second serving cell, an indication of which cell controls the cell DTX and / or DRX configuration for a cell group, wherein the indication indicates the first serving cell. In some embodiments, the indication comprises a logical channel id (LCID).

[0110] FIG. 6 is a flowchart illustrating a process 600 for facilitating intermittent channel monitoring, according to an embodiment, performed by a gNodeB Distributed Unit (gNB-DU). Process 600 may begin in step s602.

[0111] Step s602 comprises determining that a cell discontinuous transmission (DTX) and / or discontinuous reception (DRX) status has changed.

[0112] Step s604 comprises, as a result of determining that the cell DTX and / or DRX status has changed, sending towards a gNodeB Centralized Unit (gNB-CU) an indication of the cell DTX and / or DRX status having changed.

[0113] FIG. 7 is a flowchart illustrating a process 700 for facilitating intermittent channel monitoring, according to an embodiment, performed by a user equipment (UE). Process 700 may begin in step s702.

[0114] Step s702 comprises receiving an indication from a reference cell.

[0115] Step s704 comprises determining a serving cell discontinuous transmission(DTX) and / or discontinuous reception (DRX) status based on the indication.

[0116] In some embodiments, the indication includes an index for the serving cell and one or more of cell DTX / DRX state and cell DTX / DRX patterns. In some embodiments, the indication is comprised in one of a Downlink Control Indicator (DCI) message, a Medium Access Control (MAC) Control Element (CE), and a Radio Resource Control (RRC) message. In some embodiments, the reference cell is preconfigured. In some embodiments, the reference cell is provided to the UE by a network node.

[0117] FIG. 8 is a block diagram of apparatus 800 (e.g., user equipment 202, serving cell 204, network node 206, such as a Radio Link (RLC) node, or a gNB-DU), according to some embodiments, for performing the methods disclosed herein. As shown in FIG. 8, apparatus 800 may comprise: processing circuitry (PC) 802, which may include one or more processors (P) 855 (e.g., a general purpose microprocessor and / or one or more other processors, such as an application specific integrated circuit (ASIC), field-programmable gate arrays (FPGAs), and the like), which processors maybe co-located in a single housing or in a single data center or may be geographically distributed (i.e., apparatus 800 may be a distributed computing apparatus); at least one network interface 848 comprising a transmitter (Tx) 845 and a receiver (Rx) 847 for enabling apparatus 800 to transmit data to and receive data from other nodes connected to a network 810 (e.g., an Internet Protocol (IP) network) to which network interface 848 is connected (directly or indirectly) (e.g., network interface 848 may be wirelessly connected to the network 810, in which case network interface 848 is connected to an antenna arrangement); and a storage unit (a.k.a., “data storage system”) 808, which may include one or more non-volatile storage devices and / or one or more volatile storage devices. Interface 860 may connect PC 802 and storage unit 808, interface 862 may connect PC 802 and network interface 848, and interface 864 may connect network interface 848 and network 810. In embodiments where PC 802 includes a programmable processor, a computer program product (CPP) 841 may be provided.CPP 841 includes a computer readable medium (CRM) 842 storing a computer program (CP) 843 comprising computer readable instructions (CRI) 844. CRM 842 may be a non-transitory computer readable medium, such as, magnetic media (e.g., a hard disk), optical media, memory devices (e.g., random access memory, flash memory), and the like. In some embodiments, the CRI 844 of computer program 843 is configured such that when executed by PC 802, the CRI causes apparatus 800 to perform steps described herein (e.g., steps described herein with reference to the flow charts). In other embodiments, apparatus 800 may be configured to perform steps described herein without the need for code. That is, for example, PC 802 may consist merely of one or more ASICs. Hence, the features of the embodiments described herein may be implemented in hardware and / or software.

[0118] While processes in the figures may show a particular order of operations performed by certain embodiments of the present disclosure, it should be understood that such order is representative, and that alternative embodiments may perform the operations in a different order, combine certain operations, overlap certain operations, etc.

[0119] Those skilled in the art will recognize improvements and modifications to the embodiments of the present disclosure. All such improvements and modifications are considered within the scope of the concepts disclosed herein.

Claims

Claims1. A method of facilitating intermittent channel monitoring performed by a network node, the method comprising: sending, towards a user equipment (UE), a first indication that activates a serving cell for the UE; and sending a second indication, towards the UE, indicating a cell discontinuous transmission (DTX) and / or discontinuous reception (DRX) state (activated or deactivated) for the serving cell.

2. The method of claim 1, wherein the serving cell comprises a secondary cell (Scell).

3. The method of any one of claims 1-2, wherein the second indication is broadcasted toward multiple user equipments including the UE.

4. The method of claim 3, wherein the second indication is comprised in a Downlink Control Indicator (DCI).

5. A5. The method of any one of claims 1-2, wherein the second indication is sent in a message specific to the UE.

6. The method of claim 5, wherein the second indication is comprised in one of a Medium Access Control (MAC) message and a Radio Resource Control (RRC) message.

7. The method of any one of claims 1-6, wherein there is a delay T between sending the second indication after the first indication has been sent, and T is configured to allow the UE time to activate the serving cell.

8. The method of claim 7, wherein T is (or is about) 24 milliseconds.

9. The method of claim 7, wherein T is further configured to allow other user equipments time to activate the serving cell.

10. The method of any one of claims 1-9, wherein the method further comprises, prior to sending the second indication, determining that the cell DTX and / or DRX state for the serving cell has changed during a time when the serving cell was deactivated for the UE.

11. The method of any one of claims 1-10, wherein the second indication comprises separate indications for one or more cell DTX configurations and / or one or more cell DRX configurations.

12. A method of facilitating intermittent channel monitoring performed by a user equipment (UE), the method comprising: activating a serving cell for the UE; as a result of activating the serving cell for the UE, determining a cell discontinuous transmission (DTX) and / or discontinuous reception (DRX) state for the serving cell based on a default state.

13. The method of claim 12, wherein the default state is an activated state.

14. The method of any one of claims 12-13, further comprising receiving an indication from a network node to apply the default state.

15. The method of claim 14, wherein the indication is comprised in one of a Radio Resource Control (RRC) message and a Medium Access Control (MAC) message.

16. The method of any one of claims 12-15, wherein the default state is set based on one of: an initial DTX / DRX state of the serving cell, and a preconfigured value in the UE.

17. A method of facilitating intermittent channel monitoring performed by a Radio Link Control (RLC) node, the method comprising: receiving a cell discontinuous transmission (DTX) and / or discontinuous reception (DRX) configuration from a first serving cell in a cell group; and applying the cell DTX and / or DRX configuration for each cell in the cell group.

18. The method of claim 17, further comprising receiving, from a second serving cell, an indication of which cell controls the cell DTX and / or DRX configuration for a cell group, wherein the indication indicates the first serving cell.

19. The method of claim 17, wherein the indication comprises a logical channel id (LCID).

20. A method of facilitating intermittent channel monitoring performed by a gNodeB Distributed Unit (gNB-DU), the method comprising: determining that a cell discontinuous transmission (DTX) and / or discontinuous reception (DRX) status has changed; and as a result of determining that the cell DTX and / or DRX status has changed, sending towards a gNodeB Centralized Unit (gNB-CU) an indication of the cell DTX and / or DRX status having changed.

21. A method of facilitating intermittent channel monitoring performed by a user equipment (UE), the method comprising: receiving an indication from a reference cell; and determining a serving cell discontinuous transmission (DTX) and / or discontinuous reception (DRX) status based on the indication.

22. The method of claim 21, wherein the indication includes an index for the serving cell and one or more of cell DTX / DRX state and cell DTX / DRX patterns.

23. The method of any one of claims 21-22, wherein the indication is comprised in one of a Downlink Control Indicator (DCI) message, a Medium Access Control (MAC) Control Element (CE), and a Radio Resource Control (RRC) message.

24. The method of any one of claims 21-23, wherein the reference cell is preconfigured.

25. The method of any one of claims 21-23, wherein the reference cell is provided to the UE by a network node.

26. A network node comprising: processing circuitry (802); and a memory, the memory containing instructions (844) executable by the processing circuitry (802), whereby when executed the processing circuitry (802) is configured to: send, towards a user equipment (UE), a first indication that activates a serving cell for the UE; and send a second indication, towards the UE, indicating a cell discontinuous transmission (DTX) and / or discontinuous reception (DRX) state (activated or deactivated) for the serving cell.

27. The network node of claim 26, further configured to perform the method of any one of claims 2-11.

28. A user equipment (UE) comprising: processing circuitry (802); anda memory, the memory containing instructions (844) executable by the processing circuitry (802), whereby when executed the processing circuitry (802) is configured to: activate a serving cell for the UE; as a result of activating the serving cell for the UE, determine a cell discontinuous transmission (DTX) and / or discontinuous reception (DRX) state for the serving cell based on a default state.

29. The UE of claim 28, further configured to perform the method of any one of claims 13-16.

30. A Radio Link Control (RLC) node comprising: processing circuitry (802); and a memory, the memory containing instructions (844) executable by the processing circuitry (802), whereby when executed the processing circuitry (802) is configured to: receive a cell discontinuous transmission (DTX) and / or discontinuous reception (DRX) configuration from a first serving cell in a cell group; and apply the cell DTX and / or DRX configuration for each cell in the cell group.

31. The RLC node of claim 30, further configured to perform the method of any one of claims 18-19.

32. A gNodeB Distributed Unit (gNB-DU) comprising: processing circuitry (802); and a memory, the memory containing instructions (844) executable by the processing circuitry (802), whereby when executed the processing circuitry (802) is configured to:determine that a cell discontinuous transmission (DTX) and / or discontinuous reception (DRX) status has changed; and as a result of determining that the cell DTX and / or DRX status has changed, send towards a gNodeB Centralized Unit (gNB-CU) an indication of the cell DTX and / or DRX status having changed.

33. A user equipment (UE) comprising: processing circuitry (802); and a memory, the memory containing instructions (844) executable by the processing circuitry (802), whereby when executed the processing circuitry (802) is configured to: receive an indication from a reference cell; and determine a serving cell discontinuous transmission (DTX) and / or discontinuous reception (DRX) status based on the indication.

34. The UE of claim 33, further configured to perform the method of any one of claims 22-25.

35. A computer program product comprising a non-transitory machine readable storage medium including machine readable software instructions which when executed by processing circuitry of a node, causes the node to perform the method of any one of claims 1-25.

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