Method and network node for power saving of user equipment using a group of cells

Abstract

The method includes communicating with a first group of cells and receiving a first indicator, the first indicator informing a user equipment (UE) to enable scheduling with at least one second group of cells. The method further includes starting a first inactivity timer associated with the at least one second group of cells based on the first indicator, and scheduling communication with the at least one second group of cells following the step of clearing the first inactivity timer. A network node executes the method.

Description

Background Art

[0001] This application claims the benefit of U.S. Provisional Application No. 62 / 985,456, filed Mar. 5, 2020, which is hereby incorporated by reference in its entirety.

Technical Field

[0002] One or more exemplary embodiments relate to wireless communication networks.

[0003] [Related Art] The fifth generation (5G) wireless communication network is the next generation of mobile communication networks. The standards for 5G communication networks are currently being developed by the Third Generation Partnership Project (3GPP). These standards are known as the 3GPP New Radio (NR) standards.

Summary of the Invention

[0004] At least one exemplary embodiment relates to a method.

[0005] In an exemplary embodiment, the method includes communicating, by at least one processor of a user equipment (UE), with a first group of cells; receiving, by at least one processor of the user equipment (UE), a first indicator, the first indicator notifying the UE to enable scheduling with at least one second group of cells; starting, by the at least one processor, a first inactivity timer associated with the at least one second group of cells based on the first indicator; and scheduling, by the at least one processor, communication with the at least one second group of cells subsequent to starting the first inactivity timer.

[0006] In an exemplary embodiment, the group of the first cells is a cell's primary discontinuous reception (P-DRX) group, and the group of the at least one second cell is a cell's secondary discontinuous reception (S-DRX) group.

[0007] In an exemplary embodiment, the P-DRX group of the cell transmits using a lower frequency range than the S-DRX group of the cell.

[0008] In an exemplary embodiment, the first inactivity timer is a DRX-inactivity timer for a discontinuous reception (DRX) cycle of the S-DRX group of the cell.

[0009] In an exemplary embodiment, the S-DRX group includes a first physical downlink control channel (PDCCH) monitoring pattern in a first repeated discontinuous reception (DRX) cycle, the first repeated DRX cycle includes a first uplink / downlink traffic period and a first OnDuration period, the P-DRX group includes a second physical downlink control channel (PDCCH) monitoring pattern in a second repeated discontinuous reception (DRX) cycle, the second repeated DRX cycle includes a second uplink / downlink traffic period and a second OnDuration period, and the first downlink period and the first OnDuration period are each shorter than the second downlink period and the second OnDuration period.

[0010] In an exemplary embodiment, a first length of the first repeated DRX cycle is the same as a second length of the second repeated DRX cycle.

[0011] In an exemplary embodiment, the scheduling of the communication includes activating one or more cells of the group of the at least one second cell.

[0012] In an exemplary embodiment, the scheduling of the communication transmits a command to one or more cells of a group of the at least one second cell, and causes the one or more cells to switch from a dormant state to a non-dormant state.

[0013] In an exemplary embodiment, the method further comprises receiving a second indicator, the second indicator indicating that a group of the at least one second cell is in a dormant state, and stopping the first inactivity timer and the DRX OnDuration timer based on the receiving of the second indicator.

[0014] In an exemplary embodiment, the method further comprises receiving a second indicator, the second indicator indicating that a group of the at least one second cell group is in a dormant state, and ensuring that the DRX OnDuration timer is not started based on the receiving of the second indicator.

[0015] At least another exemplary embodiment includes a network node.

[0016] In an exemplary embodiment, the network node includes a memory containing computer-readable instructions, and at least one processor reads and executes the computer-readable instructions to communicate with a group of first cells, receive a first indicator, the first indicator notifying the network node to enable scheduling with a group of at least one second cell, start a first inactivity timer associated with the group of the at least one second cell based on the first indicator, and schedule communication with the group of the at least one second cell subsequent to the starting of the first inactivity timer.

[0017] In an exemplary embodiment, the group of the first cells is a primary discontinuous reception (P-DRX) group of cells, and the group of the at least one second cell is a secondary discontinuous reception (S-DRX) group of cells.

[0018] In an exemplary embodiment, the P-DRX group of cells transmits using a lower frequency range than the S-DRX group of cells.

[0019] In an exemplary embodiment, the first inactivity timer is a DRX-inactivity timer for a discontinuous reception (DRX) cycle of the S-DRX group of cells.

[0020] In an exemplary embodiment, the S-DRX group includes a first physical downlink control channel (PDCCH) monitoring pattern with a first repeated discontinuous reception (DRX) cycle, the first repeated DRX cycle includes a first uplink / downlink traffic period and a first OnDuration period, the P-DRX group includes a second physical downlink control channel (PDCCH) monitoring pattern with a second repeated discontinuous reception (DRX) cycle, the second repeated DRX cycle includes a second uplink / downlink traffic period and a second OnDuration period, and the first downlink period and the first OnDuration period are each shorter than the second downlink period and the second OnDuration period.

[0021] In an exemplary embodiment, the first length of the first repeated DRX cycle is the same as the second length of the second repeated DRX cycle.

[0022] In an exemplary embodiment, the at least one processor schedules the communication by activating one or more cells of the group of the at least one second cell.

[0023] In an exemplary embodiment, the at least one processor schedules the communication by sending a command to switch one or more cells from a dormant state to a non-dormant state to one or more cells of one of the at least one second cell groups.

[0024] In an exemplary embodiment, the at least one processor further performs the step of receiving a second indicator, wherein the second indicator indicates that the at least one second cell group is in a dormant state, and based on the receiving of the second indicator, stopping the first inactivity timer and the DRX OnDuration timer.

[0025] In an exemplary embodiment, the at least one processor further performs the step of receiving a second indicator, wherein the second indicator indicates that the at least one second cell group is in a dormant state, and based on the receiving of the second indicator, ensuring that the DRX OnDuration period timer is not started.

[0026] Exemplary embodiments are more fully understood from the following detailed description of the specification and the accompanying drawings, wherein like elements are represented by like reference numerals, which are given for purposes of illustration only and thus do not limit the present disclosure.

Brief Description of the Drawings

[0027]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

[0028] Note that these figures are intended to illustrate the overall features of the methods, structures, and / or materials utilized in some exemplary embodiments and to supplement the description provided below. However, these drawings are not to scale and may not accurately reflect the exact structure or performance characteristics of any given embodiment, and should not be construed as defining or limiting the range of values or characteristics encompassed by the exemplary embodiments. The use of similar or identical reference numbers in the various drawings is intended to indicate the presence of similar or identical elements or features.

DETAILED DESCRIPTION OF THE INVENTION

[0029] Here, various exemplary embodiments will be described more fully with reference to the accompanying drawings in which some exemplary embodiments are shown.

[0030] Specific detailed exemplary embodiments are disclosed herein. However, the specific structural and functional details disclosed herein are merely representative for the purpose of describing the exemplary embodiments. However, the exemplary embodiments may be embodied in many alternative forms and should not be construed as limited to only the embodiments described herein.

[0031] It should be understood that there is no intention to limit the exemplary embodiments to the specific forms disclosed. Rather, the exemplary embodiments include all modifications, equivalents, and alternative forms that fall within the scope of the present disclosure. Like numbers refer to like elements throughout the description of the figures.

[0032] One or more exemplary embodiments may be described from the perspective of wireless network elements (e.g., gNB), user equipment, etc., but it should be understood that one or more exemplary embodiments described herein may be executed by one or more processors (or processing circuits) in an applicable device. For example, according to one or more exemplary embodiments, at least one memory may contain or be capable of storing computer program code, and at least one memory and the computer program code may be configured to cause at least one processor to perform the operations described herein in a wireless network element (or user equipment).

[0033] It will be understood that several exemplary embodiments can be used in combination.

[0034] FIG. 1 shows a simplified diagram of a portion of a 3GPP (3rd Generation Partnership Project) NR (New Radio) access network 10 for explaining an exemplary embodiment. The 3GPP NR radio access deployment includes a base station (e.g., gNB 102) having transmission and reception points (TRPs) 102a, 102b, 102c. Each of the TRPs 102a, 102b, 102c may be, for example, a remote radio head (RRH) or a remote radio unit (RRU) including at least, for example, a radio frequency (RF) antenna (or antennas) or an antenna panel for transmitting and receiving data within a geographical area, and a radio transceiver. In an exemplary embodiment, the TRPs 102a, 102b, 102c can be regarded as secondary cells (SCells) from the perspective that they are smaller cells that communicate in conjunction with a larger cell (e.g., gNB 102). The TRPs 102a, 102b, 102c provide cellular resources to user equipments (UEs) 106a, 106b, 106c within a geographical coverage area. In some cases, the baseband processing may be split between the TRPs 102a, 102b, 102c and the gNB 102 in a 5th generation (5G) cell. Alternatively, the baseband processing may be executed at the gNB 102. In the example shown in FIG. 1, the TRPs 102a, 102b, 102c are configured to communicate with a UE (e.g., UE 106a) via one or more transmit (TX) / receive (RX) beam pairs. The gNB 102 communicates with a network core 1 called New Core in 3GPP NR.

[0035] The TRPs 102a, 102b, 102c may have independent schedulers, or the gNB 102 may perform joint scheduling among the TRPs 102a, 102b, 102c.

[0036] It should be understood that gNB 102 and TRPs 102a, 102b, 102c can provide communication services to a relatively large number of UEs 106a, 106b, 106c within the coverage areas of TRPs 102a, 102b, 102c. For ease of understanding of the exemplary embodiments, the communication services (including transmission and reception of wireless signals) are mainly described between gNB 102, TRP 102a and / or UE 106a, but it should be understood that signals can be transmitted between any of gNB 102, TRPs 102a, 102b, 102c, and any of UEs 106a, 106b, 106c.

[0037] FIG. 2 shows a block diagram of gNB 102 (illustrated in FIG. 1) according to an exemplary embodiment. As shown, gNB 102 includes a memory 240, a processor 220 connected to the memory 240, various interfaces 260 connected to the processor 220, and one or more antennas or antenna panels 265 connected to the various interfaces. The various interfaces 260 and antennas 265 can constitute a transceiver for transmitting / receiving data between gNB 102 via a plurality of wireless beams or between gNB 102 and a plurality of TRPs 102a, 102b, 102c, etc. As understood, depending on the implementation form of gNB 102, gNB 102 may include more components than those shown in FIG. 2. However, for disclosing the exemplary embodiments, it is not necessary to show all of these components.

[0038] Memory 240 can be a computer-readable storage medium generally including a random access memory (RAM), a read-only memory (ROM), and / or a permanent mass storage device such as a disk drive. Memory 240 also stores an operating system and any other routines / modules / applications for providing the functions of gNB 102 (e.g., the functionality of the gNB, the methods according to exemplary embodiments, etc.) to be executed by processor 220. These software components can also be loaded from a separate computer-readable storage medium into memory 240 using a drive mechanism (not shown). Such a separate computer-readable storage medium can include a disk, a tape, a DVD / CD-ROM drive, a memory card, or other similar computer-readable storage media (not shown). In some exemplary embodiments, the software components can be loaded into memory 240 via one of the various interfaces 260 rather than via a computer-readable storage medium.

[0039] Processor 220 can be configured to execute the instructions of a computer program by performing arithmetic, logical, and input / output operations of the system. The instructions can be provided to processor 220 by memory 240.

[0040] The various interfaces 260 can include components that interface processor 220 with antenna 265 or other input / output components. As will be appreciated, the various interfaces 260 and programs stored in memory 240 to describe the dedicated functions of gNB 102 will vary depending on the implementation of gNB 102.

[0041] Interface 260 can also include one or more user input devices (e.g., a keyboard, a keypad, a mouse, etc.) and user output devices (e.g., a display, a speaker, etc.).

[0042] Although not specifically discussed herein, the configuration shown in FIG. 2 can be utilized, inter alia, to implement TRP102a, 102b, 102c, other radio access and backhaul network elements and / or devices. In this regard, for example, the memory 240 can store an operating system and any other routines / modules / applications for providing functions such as TRP to be executed by the processor 220 (e.g., functions of these elements, methods according to exemplary embodiments, etc.).

[0043] FIG. 3 shows a block diagram of a user equipment (UE) 106a according to an exemplary embodiment. It should be understood that other UEs 106b, 106c have the same structure. UE 106a is a device used by an end user to communicate via the 3GPP NR radio access deployment shown in FIG. 1. Examples of UEs include cellular phones, smartphones, tablets, computers, laptop computers, and the like.

[0044] As shown in the figure, UE 106a includes a memory 340, a processor 320 connected to the memory 340, various interfaces 360 connected to the processor 320, and one or more antennas or antenna panels 365 connected to the various interfaces 360. The various interfaces 360 and antennas 365 can constitute a transceiver for transmitting / receiving data to / from the gNB 102 or to / from a plurality of TRPs 102a, 102b, 102c, etc. via a plurality of wireless beams. As can be understood, depending on the implementation form of UE 106a, UE 106a can include more components than those shown in FIG. 3. However, in order to disclose exemplary embodiments, it is not necessary to show all of these common conventional components.

[0045] Memory 340 can be a computer-readable storage medium generally including a random access memory (RAM), a read-only memory (ROM), and / or a permanent mass storage device such as a disk drive. Memory 340 also stores an operating system and any other routines / modules / applications for providing the functions of UE106a to be executed by processor 320 (e.g., UE functions, methods according to exemplary embodiments, etc.). These software components can also be loaded into memory 340 from a separate computer-readable storage medium using a drive mechanism (not shown). Such separate computer-readable storage media can include disks, tapes, DVD / CD-ROM drives, memory cards, or other similar computer-readable storage media (not shown). In some exemplary embodiments, the software components can be loaded into memory 340 via one of the various interfaces 360 rather than via a computer-readable storage medium.

[0046] Processor 320 can be configured to execute instructions of a computer program by performing arithmetic, logical, and input / output operations of the system. The instructions can be provided to processor 320 by memory 340.

[0047] The various interfaces 360 can include components that interface processor 320 with antenna 365 or other input / output components. As will be appreciated, the various interfaces 360 and programs stored in memory 340 to describe the dedicated functions of UE106a will vary depending on the implementation of UE106a.

[0048] Interface 360 can also include one or more user input devices (e.g., keyboard, keypad, mouse, etc.) and user output devices (e.g., display, speaker, etc.).

[0049] [General Concepts] In an exemplary embodiment, a wake-up signal (WUS) enables UE106a to skip physical downlink control channel (PDCCH) monitoring during a planned monitoring period (the "OnDuration" period) when there is no data transmission to be sent. When core 1 of network (NW) 10 attempts to schedule UE106a, core 1 needs to send wake-up signaling (WUS) to UE106a during a WUS opportunity to start a drx-onDuration timer for UE106a. When a WUS opportunity is notified via WUS, UE106a monitors a normal PDCCH to schedule data during the upcoming OnDuration.

[0050] In 3GPP, WUS is an indicator (DCP) called downlink control information (DCI) with a cyclic redundancy check (CRC) scrambled by a power saving radio network temporary identity (PS-RNTI). In an alternative expression, WUS or DCP may be called a physical downlink control channel (PDCCH) transmission carrying a wake-up indication. This wake-up indication may include an indication for the UE to determine whether (or not) to start a drx-onDuration timer at the next occurrence of the timer, and may further include an indication regarding the SCell and / or SCell group inactivity state.

[0051] When DRX is configured, the terminal device does not need to continuously monitor the PDCCH. DRX is characterized as follows. - on-duration: The period after wake-up during which the UE waits to receive the PDCCH. If the UE successfully decodes the PDCCH, the UE remains awake and starts an inactivity timer. - Inactive Timer: The period from the last successful PDCCH decoding to wait for successfully decoding the PDCCH, but if it fails, it can return to the sleep state. The UE restarts the inactive timer after a single successful decoding of the PDCCH only for the first transmission (i.e., not for retransmissions). - Retransmission Timer: The duration until retransmission can be predicted. - Cycle: Specifies the periodic repetition of the on-duration during which the possible inactive period continues. - Active Time: The total duration during which the UE monitors the PDCCH. This includes the "on-duration" of the DRX cycle, the time during which the UE performs continuous reception while the inactive timer has not expired, and the time during which the UE performs continuous reception while waiting for a retransmission opportunity.

[0052] In addition, when the UE is configured accordingly, the DCP received on the active BWP can indicate whether it is necessary to monitor the PDCCH during the next occurrence of the on-duration. By default, if no DCP is detected on the active BWP, the UE does not monitor the PDCCH during the next occurrence of the on-duration. However, in this case, it is also possible to configure the opposite behavior, i.e., to monitor the PDCCH during the next occurrence of the on-duration.

[0053] When connected-mode DRX is configured, the UE may be configured to monitor the DCP only at an offset configured, if any, before the on-duration. Multiple monitoring opportunities may be configured before the on-duration. The UE does not monitor the DCP during opportunities that occur during the active time, measurement interval, or BWP switching, and in that case, monitors the PDCCH during the next on-duration. If no DCP is set for the active BWP, the UE follows the normal DRX operation.

[0054] [Discontinuous Reception (DRX) Cycle] Figure 4 shows a discontinuous reception (DRX) cycle 400 for UE106a in an exemplary embodiment. PDCCH monitoring is performed during these DRX cycles 400. Specifically, the PDCCH monitoring activity for UE106a in radio resource control (RRC) connected mode is governed by DRX cycle 400, bandwidth adaptation (BA), and DCP.

[0055] In an exemplary embodiment, when the DRX cycle 400 is configured, UE106a does not need to continuously monitor the PDCCH, whereby UE106a can reduce power consumption. The DRX cycle 400 is characterized by several elements including an on - duration time 402, an inactivity timer, a retransmission timer, and an active time. The on - duration time 402 is the duration that UE106a waits to receive the PDCCH for UE106a after waking up. If UE106a successfully decodes the PDCCH, UE106a remains awake and starts the inactivity timer. In an exemplary embodiment, the inactivity timer is a timer that manages the duration that UE106a waits for a successful PDCCH decoding from the last successful decoding of the PDCCH, and upon failure, UE106a returns to sleep. UE106a shall restart the inactivity timer after a single successful decoding of the PDCCH only for the first transmission (i.e., not for retransmissions). The retransmission timer is a timer that controls the time until retransmission can be expected. The active time is the time that governs the total duration during which UE106a monitors the PDCCH. This includes the "on - duration" 402 of the DRX cycle 400, the time during which UE106a performs continuous reception while the inactivity timer has not expired, and the time during which UE106a performs continuous reception while waiting for a retransmission opportunity. The DRX cycle 400 is a periodic repetition of the on - duration 402, followed by a possible inactivity period 404.

[0056] In an exemplary embodiment, BA is configured such that UE106a must monitor the PDCCH only on one active bandwidth part (BWP). That is, UE106a does not need to monitor the PDCCH across the entire downlink (DL) frequency of the cell. In an exemplary embodiment, a BWP inactivity timer (independent of the above-mentioned DRX inactivity timer) is used to switch the active BWP to the default BWP. The timer is restarted upon successful PDCCH decoding, and the switch to the default BWP is made upon expiration. In 5G, a BWP is a continuous set of physical resource blocks (PRBs) on a given carrier.

[0057] In an exemplary embodiment, UE106a is notified by the DCP received on the active BWP to monitor or not monitor the PDCCH during the next occurrence of on-duration 402. In an exemplary embodiment, by default, if UE106a does not detect a DCP on the active BWP, UE106a does not monitor the PDCCH during the next occurrence of on-duration 402. However, in an exemplary embodiment, UE106a may alternatively be configured to monitor the PDCCH during the next occurrence of on-duration.

[0058] In an exemplary embodiment, UE106a is configured to monitor the DCP, optionally during an offset configured prior to on-duration 402, only when connected-mode DRX is configured. In an exemplary embodiment, multiple monitoring opportunities can be configured prior to on-duration. In an exemplary embodiment, UE106a does not monitor the DCP during opportunities that occur during active time, measurement gaps, or BWP switches, in which case UE106a monitors the PDCCH during the next on-duration. It should be understood that the DCP is a wake-up indication that starts or does not start the DRX "on-Duration" timer in UE106a. In an exemplary embodiment, if the DCP is not configured on the active BWP, UE106a follows normal DRX operation.

[0059] In an exemplary embodiment, when carrier aggregation (CA) is configured, the DCP is configured only on the SpCell, where the SpCell means the Primary Cell (PCell) of the Master Cell Group (MCG) or the Primary Secondary Cell (PSCell) of the Secondary Cell Group (SCG).

[0060] In an exemplary embodiment, one DCP is configured to independently control PDCCH monitoring during the on-duration 402 for one or more UEs 106.

[0061] In an exemplary embodiment, power saving in the Radio Resource Control idle mode (RRC_IDLE) and the Radio Resource Control inactive mode (RRC_INACTIVE) can be achieved by the UE 106a relaxing adjacent cell radio resource measurements (RRM) when it is determined that the UE 106a is in a low mobility scenario or is not at the cell edge. In an exemplary embodiment, the DCP can be configured in the RRC_INACTIVE or RRC_IDLE mode.

[0062] In an exemplary embodiment, power saving of the UE 106a is enabled by adapting the maximum number of DL layers of multiple input multiple output (MIMO) by means of BWP switching.

[0063] In an exemplary embodiment, power saving is enabled during active time via cross-slot scheduling, which promotes the UE106a to achieve power saving using the assumption that the UE106a will not be scheduled to receive the physical downlink shared channel (PDSCH), up to the minimum scheduling offsets K0 and K2, to receive channel state information (A-CSI) or be triggered to transmit a physical uplink control channel (PUSCH) scheduled by the PDCCH. In an exemplary embodiment, the dynamic adaptation of the minimum scheduling offsets K0 and K2 is controlled by the PDCCH.

[0064] [Resting BWP of SCell] In an exemplary embodiment, the "resting" behavior involves multiple BWPs. In an exemplary embodiment, for example, the resting behavior includes at most one BWP that is the resting BWP, and one BWP that is a non-resting BWP (or the first BWP after resting or the BWP to which the UE switches from the resting BWP), or alternatively, one BWP that is the resting BWP and other BWPs that are regular BWPs. The resting BWP is a BWP without PDCCH monitoring having limited UL operation or no UL operation. In an exemplary embodiment, the network core 1 can switch between the resting BWP and the non-resting BWP using a "1-bit indication" (1-bit identifier or indicator) or the like that can be transmitted during active time or outside active time (with slightly different signaling). In other words, in an exemplary embodiment, when the network core 1 notifies the UE106a to switch from the resting BWP to the non-resting BWP by transmitting an indicator to the UE106a via the processor 220 of the gNB102 that transmits the indicator to the UE106a, the UE106a switches from the resting BWP to the first non-resting BWP ID (for PDCCH monitoring). The first non-resting BWP ID may be different during active time compared to during active time.

[0065] [Resting / Non-resting Monitoring] In an exemplary embodiment, PDCCH monitoring and wake-up / sleep behavior for a SCell includes the following.

[0066] UE106a is configured using DRX mode operation via the PCell or via the SCell.

[0067] The position in DCI format 2_6 of the wake-up indication bit is at PSPositionDCI2-6.

[0068] Here, when the value of the "PDCCH monitoring" bit is "0", UE106a does not start the drx-onDuration timer for the next long DRX cycle 400.

[0069] UE106a starts the drx-onDuration timer for the next long DRX cycle 400 when the value of the "PDCCH monitoring" bit is "1".

[0070] In an exemplary embodiment, the bitmap when UE106a is provided with a group of some configured SCells by SCell-groups-for-dormancy-outside-active-time occurs at the following timing.

[0071] When the bitmap position is immediately after the "PDCCH monitoring" bit position.

[0072] When the bitmap size is equal to the number of configured SCell groups and each bit of the bitmap corresponds to a configured SCell group from the number of configured SCell groups.

[0073] When a "0" value for a bit of the bitmap indicates the active DL BWP provided by the inactive BWP for each activated SCell in the corresponding group of SCells for UE106a.

[0074] When indicating the active DL BWP provided by first-non-dormant-BWP-ID-for-DCI-outside-active-time for each activated SCell within the corresponding group of SCell configured with a value of "1" for the bits of the bitmap, for UE106a.

[0075] The DCP is a wake-up indication for either starting or not starting the drx-onDuration timer in UE106a, and the bitmap is an indication regarding the dormant state of the configured group of SCell102a, 102b, 102c at the start of the drx-onDuration timer. The bitmap indication regarding the dormant state may be configurable and can be configured when the UE is configured with SCell dormancy.

[0076] In an exemplary embodiment, UE106a can be configured for up to 5 groups of the configured SCell102a, 102b, 102c for dedicated dormant behavior, and each group can consist of several (one or more) SCell. In one example, UE106a can also be configured with more than 5 groups.

[0077] [Multiple DRX groups] FIG. 5 illustrates a configuration with multiple DRX groups according to an exemplary embodiment. In the exemplary embodiment, this configuration can include a first group of one PCell and zero or more SCell102y, and a second group of one or more SCell102z. In the exemplary embodiment, the PCell and optionally SCell102y transmit using the first frequency range FR1, and SCell102z transmits using the second frequency range FR2. In the exemplary embodiment, the first frequency range FR1 uses a lower frequency range compared to the second frequency range FR2. In the exemplary embodiment, the PCell can also be associated with the second group 102z.

[0078] In an exemplary embodiment, both the FR1 and FR2 cells are configured via carrier aggregation. In an exemplary embodiment, the FR2 cell can be configured using a separate (and shorter) drx-inactivity timer (406b) and drx-OnDuration timer (402b) compared to the drx-inactivity timer (406a) and drx-OnDuration timer (402a) of the FR1 cell. The lengths of the long DRX cycles 400a / b and the short DRX cycles, when configured, are common to both FR1 and FR2. In an exemplary embodiment, the FR2 cell sleeps more quickly compared to the FR1 cell, thereby reducing power consumption. In an exemplary embodiment, the first group of the PCell and zero or more SCell may be referred to as the primary DRX group, and the second group of one or more SCell may be referred to as the secondary DRS group.

[0079] In an exemplary embodiment, separate drx-inactivity timer (406b) and drx-onDuration timer (402b) can be configured for the secondary DRX group (FR2 cell). In an exemplary embodiment, the combination of cross-carrier scheduling and the secondary DRX group 102z is not supported.

[0080] In an exemplary embodiment, the timers (406b / 402b) for the FR2 DRX configuration are shorter than the timers (406a / 402a) for the FR1 DRX configuration. In an exemplary embodiment, the secondary DRX configuration can be applied to the FR2 cell and the existing DRX configuration can be applied to the FR1 cell. In an exemplary embodiment, the secondary DRX configuration can be applied to the FR1 cell and the existing DRX configuration can be applied to the FR2 cell. Note that the DRX group can be formed from the PCell and one or more SCell configured by other means without considering the frequency range.

[0081] [Technical problems solved by some exemplary embodiments] In an exemplary embodiment, a second group of one or more SCell102z is a secondary DRX (S-DRX) group, and a first group of a PCell and zero or more SCell102y is a primary DRX (P-DRX) group. In an exemplary embodiment, the S-DRX group configuration operates with values of a shorter drx-inactivity timer 406b and a drx-onDuration timer 402b as compared to the primary DRX (P-DRX) group configuration, and the S-DRX group may sleep before the P-DRX group. In an exemplary embodiment, since cross-carrier scheduling via a DRX group may not be supported, NW10 cannot restart the drx-inactivity timer 406b for the S-DRX group, for example, when DL data suddenly becomes available for transmission after expiration of the drx-inactivity timer 406b. In an exemplary embodiment, this will force the data to be transmitted via the P-DRX group cell 102z until the data is completely transmitted or the next DRX-onDuration timer opportunity becomes available, resulting in the cells within the S-DRX group becoming schedulable.

[0082] [Summary of Some Exemplary Embodiments] In some exemplary embodiments, when the network 10 indicates via the primary DRX group 102y that at least one SCell group 102z should switch from a dormant BWP to a non-dormant BWP, the processor 320 of the UE106a starts / restarts the drx-inactivity timer 406b associated with the secondary DRX group 102z. In an exemplary embodiment, this is accomplished to enable scheduling with the S-DRX group 102z when the UE106a is no longer in active time or when the UE106a will enter DRX during a BWP switching period within the S-DRX group.

[0083] In some embodiments, the drx-inactivity timer 406b associated with the S-DRX group 102z is started / restarted by the processor 320 of the UE 106a only when one or more SCell 102z associated with the S-DRX group are switched from a dormant BWP to a non-dormant BWP.

[0084] In some exemplary embodiments, the NW 10 can also trigger the start / resumption of the drx-inactivity timer 406b associated with the S-DRX group by instructing (notifying) the SCell group 102z already operating on a non-dormant BWP (or any other BWP that is not a dormant BWP) that the SCell group 102z is moving to the non-dormant BWP. In some exemplary embodiments, the processor 320 of the UE 106a, in this case, either switches the BWP of each associated SCell 102z to the non-dormant BWP or retains the current BWP that is active within each associated SCell 102z.

[0085] In some exemplary embodiments, when the network 10 instructs (notifies) to switch all SCell groups 102z associated with the S-DRX group from a BWP (non-dormant, normal, etc.) to a dormant BWP, the processor 320 of the UE 106a stops the drx-onDuration timer 402b and the drx-inactivity timer 406b associated with the S-DRX group.

[0086] In some exemplary embodiments, when the WUS instructs (notifies) all SCell groups 102z associated with the S-DRX group to remain / switched to the dormant BWP, the processor 320 of the UE 106a does not start the drx-onDuration timer 402b associated with the S-DRX group at the next drx-onDuration timer 406b opportunity.

[0087] In some exemplary embodiments, if WUS is missed by UE106a due to being in the P-DRX group 102y and active time, and all SCell groups 102z associated with the S-DRX group are configured with a dormant BWP, the processor 320 of UE106a does not start the drx-onDuration timer 402b for the S-DRX group at the next opportunity. Instead, the processor 320 of UE106a activates the drx-onDuration timer 402b and switches the SCell / SCell group 102z to a non-dormant BWP according to the method proposed in, for example, U.S. Patent Application No. 62 / 975,356, "Method for Enabling Secondary Cell Dormancy for User Equipment Power Savings", filed on February 12, 2020.

[0088] In some exemplary embodiments, all SCell / SCell groups 102z associated with the S-DRX group are implicitly assumed to be in a dormant state after the drx-inactivity timer 406b associated with the S-DRX group expires. In an exemplary embodiment, the DRX-inactivity timer 406a can also be associated with the primary DRX group 102y.

[0089] In some exemplary embodiments, when an SCell 102z belonging to the S-DRX group is configured but not activated, and the SCell 102z is activated by a network indicator (such as a DCI command, a MAC activation / deactivation command, etc.) via a cell in the primary DRX group (or implicitly activated based on some timer), the drx-inactivity timer 406b of the secondary DRX group is started.

[0090] In some exemplary embodiments, when all SCell102z belonging to the S-DRX group are deactivated (by an explicit indication by NW10 or the SCell deactivation timer), the processor 320 of UE106a stops the drx-onDuration timer 402b and the drx-inactivity timer 406b associated with the S-DRX group.

[0091] In some exemplary embodiments, NW10 can configure UE106a (by sending instructions stored in memory 340 to processor 320) according to various options as presented above.

[0092] In an exemplary embodiment, when there is data activity when the S-DRX group 102z has already switched to DRX, or when there is data activity when the P-DRX group 102y has not switched to DRX, at least one of the drx-onDuration timer 402b and the drx-inactivity timer 406b associated with the S-DRX group started by NW10 can be activated using existing signaling.

[0093] In an exemplary embodiment, additional power savings can be achieved when the SCell102z associated with the S-DRX group can be put into a dormant state during a period.

[0094] [Exemplary Method According to Some Exemplary Embodiments] FIG. 6 illustrates a method for power saving for a UE using multiple DRX groups in an exemplary embodiment. It should be understood that these steps are executed by the processor 320 of UE106a.

[0095] In one embodiment, as shown in step S500, the processor 320 of the UE106a communicates with a first group of cells. In an exemplary embodiment, the first group of cells is the PCell of FIG. 5 and zero or more SCell102y.

[0096] In one embodiment, as shown in step S502, the processor 320 of the UE106a receives a first indicator, and the first indicator notifies the UE to enable scheduling with at least one second group of cells. In an exemplary embodiment, the at least one second group of cells is the SCell102z of FIG. 5.

[0097] In one embodiment, as shown in step S504, the processor 320 of the UE106a starts a first inactivity timer 406b associated with a group of at least one second cell 102z based on the first indicator (see FIG. 5).

[0098] In one embodiment, as shown in step S506, the processor 320 of the UE106a schedules communication with a group of at least one second cell 102z following the start of the first inactivity timer 406b.

[0099] Terms such as first, second, etc. may be used herein to describe various elements, but these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of the present disclosure, a first element can be referred to as a second element, and similarly, a second element can be referred to as a first element. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0100] When an element is referred to as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element, or intervening elements may be present. In contrast, when an element is referred to as being "directly connected" or "directly coupled" to another element, intervening elements are absent. Other terms used to describe the relationship between elements should be interpreted in a similar manner (e.g., "between", "directly between", "adjacent", "directly adjacent", etc.).

[0101] The terms used in this specification are for the purpose of describing particular embodiments only and are not intended to be limiting. As used in this specification, the singular forms "a", "an", and "the" are to be construed to include the plural forms as well, unless the context clearly dictates otherwise. Further, the terms "comprises", "comprising", "includes", and / or "including" when used in this specification specify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0102] Also, in some alternative implementations, the described functions / operations may occur in a different order than that shown in the drawings. For example, two figures shown in succession may in fact be executed substantially simultaneously, depending on the functions / operations involved, or in the reverse order in some cases.

[0103] In the following description, specific details are provided to provide a thorough understanding of the exemplary embodiments. However, it will be understood by those skilled in the art that the exemplary embodiments may be practiced without these specific details. For example, the system may be shown in block diagrams so as not to obscure the exemplary embodiments with unnecessary detail. In other instances, well-known processes, structures, and techniques may be shown without unnecessary detail in order to avoid obscuring the exemplary embodiments.

[0104] As described herein, exemplary embodiments may be implemented as acts of operations and symbolic representations (e.g., in the form of flowcharts, flow diagrams, data flow diagrams, structure diagrams, block diagrams, etc.) of program modules or functional processes that include routines, programs, objects, components, data structures, etc., which perform specific tasks or implement specific abstract data types and may be implemented using existing hardware in existing user equipment, base stations, evolved Node Bs (eNBs), remote radio heads (RRHs), 5G base stations (gNBs), femto base stations, network controllers, computers, etc. Such existing hardware may be one or more processors, one or more central processing units (CPUs), one or more controllers, one or more arithmetic logic units (ALUs), one or more digital signal processors (DSPs), one or more microcomputers, one or more field programmable gate arrays (FPGAs), one or more system-on-chips (SoCs), one or more programmable logic units (PLUs), one or more microprocessors, one or more application specific integrated circuits (ASICs), or any other one or more devices capable of responding to and executing instructions in a defined manner, but is not limited thereto, and may be processing or control circuitry.

[0105] Flowcharts may describe operations as sequential processes, but many of the operations may be performed in parallel, simultaneously, or during the same period. In addition, the order of the operations may be rearranged. A process may terminate when its operations are completed, but may have additional steps not included in the figure. A process may correspond to a method, function, procedure, subroutine, subprogram, etc. When a process corresponds to a function, its termination may correspond to the return of the function to the calling function or main function.

[0106] As disclosed herein, the terms "memory medium", "computer-readable memory medium", or "non-transitory computer-readable memory medium" may represent one or more devices for storing data, including read-only memory (ROM), random access memory (RAM), magnetic RAM, core memory, magnetic disk storage media, optical storage media, flash memory devices and / or other tangible machine-readable media for storing information. The term "computer-readable medium" may include, but is not limited to, portable or fixed storage devices, optical storage devices, and various other media capable of storing, containing, or transporting instructions and / or data.

[0107] Furthermore, exemplary embodiments may be implemented by hardware, software, firmware, middleware, microcode, a hardware description language, or any combination thereof. When implemented in software, firmware, middleware, or microcode, the program code or code segments for performing the necessary tasks may be stored in a machine-readable medium such as a computer-readable memory medium or a computer-readable medium. When implemented in software, one or more processors perform the necessary tasks. For example, as described above, according to one or more exemplary embodiments, at least one memory may include or be capable of storing computer program code, and at least one memory and computer program code may be configured to cause at least one processor to perform the necessary tasks for a network element or network device. Further, the processor, memory, and exemplary algorithms are encoded as computer program code and act as means for providing or causing the execution of the operations discussed herein.

[0108] A code segment of computer program code can represent a procedure, a function, a subprogram, a program, a routine, a subroutine, a module, a software package, a class, or any combination of instructions, data structures, or program statements. A code segment can be coupled to another code segment or a hardware circuit by passing and / or receiving information, data, arguments, parameters, or memory contents. Information, arguments, parameters, data, etc. can be passed, transferred, or transmitted via any suitable techniques including memory sharing, message passing, token passing, network transmission, etc.

[0109] As used herein, the terms “including” and / or “having” are defined as comprising (i.e., open language). As used herein, the term “coupled” is defined as being connected, although not necessarily directly and not necessarily mechanically. Terms derived from the term “indicating” (e.g., “indicates” and “indication”) are intended to encompass all various techniques available for communicating or referring to the indicated object / information. Some examples of techniques available for communicating or referring to the indicated object / information, although not all, include conveying the indicated object / information, conveying an identifier of the indicated object / information, conveying information used to generate the indicated object / information, conveying some parts or portions of the indicated object / information, conveying some derivation of the indicated object / information, and conveying some symbol representing the indicated object / information.

[0110] According to an exemplary embodiment, a user equipment, a base station, an eNB, an RRH, a gNB, a femto base station, a network controller, a computer, etc. can be (or can include) hardware, firmware, hardware that executes software, or any combination thereof. Such hardware may include, but is not limited to, one or more processors, one or more CPUs, one or more controllers, one or more ALUs, one or more DSPs, one or more microcomputers, one or more FPGAs, one or more SoCs, one or more PLUs, one or more microprocessors, one or more ASICs, etc., and may include processing or control circuitry, or can be any other (single or plural) device that can respond to and execute instructions in a defined manner.

[0111] Benefits, other advantages, and solutions to problems have been described above with respect to specific embodiments of the present disclosure. However, benefits, advantages, solutions to problems, and any element that can cause, bring about, or make more prominent such benefits, advantages, or solutions should not be construed as important, necessary, or essential features or elements of any or all of the claims.

Claims

1. performing, by at least one processor of a user equipment (UE), communication with a first group of cells; receiving, by at least one processor of the user equipment (UE), a first indicator, the first indicator notifying the UE to enable scheduling with at least one second group of cells; starting, by the at least one processor, a first inactivity timer associated with the at least one second group of cells based on the first indicator, the first inactivity timer being shorter than a second inactivity timer associated with at least one of the first group of cells; scheduling, by the at least one processor, communication with the at least one second group of cells following the starting of the first inactivity timer; the first group of cells being a cell's primary discontinuous reception (P-DRX) group; the at least one second group of cells being a cell's secondary discontinuous reception (S-DRX) group; the step of scheduling the communication includes transmitting a command to one or more cells within the at least one second group of cells to switch the one or more cells from a dormant state to a non-dormant state; the UE is configured to use discontinuous reception (DRX) mode operation via the first group of cells or the second group of cells; When the value of the physical downlink control channel (PDCCH) monitoring bit is 0, the UE does not start the drx-onDuration timer for the next long DRX cycle, and when the value of the PDCCH monitoring bit is 1, the UE starts the drx-onDuration timer for the next long DRX cycle, a method in which the position of the wake-up indication bit in the DCI format is set to a first position. **Claim 2** The method according to claim 1, wherein the P-DRX group of the cell transmits using a lower frequency range than the S-DRX group of the cell. **Claim 3** The method according to claim 1 or 2, wherein the first inactivity timer is a DRX inactivity timer for a discontinuous reception (DRX) cycle of the S-DRX group of the cell. **Claim 4** The S-DRX group includes a first physical downlink control channel (PDCCH) monitoring method in a first repeated discontinuous reception (DRX) cycle, and the first repeated DRX cycle includes a first uplink / downlink traffic period and a first OnDuration period, The P-DRX group includes a second physical downlink control channel (PDCCH) monitoring method in a second repeated discontinuous reception (DRX) cycle, and the second repeated DRX cycle includes a second uplink / downlink traffic period and a second OnDuration period, The method according to claim 1, wherein the first downlink period and the first OnDuration period are each shorter than the second downlink period and the second OnDuration period. **Claim 5** The method according to claim 4, wherein the first length of the first repeated DRX cycle is the same as the second length of the second repeated DRX cycle. **Claim 6** The step of scheduling the communication includes activating one or more cells of one of the groups of the at least one second cell, according to the method of claim 1.

7. The step of scheduling the communication is a step of transmitting a command to one or more cells of one of the groups of the at least one second cell, further including the step of switching the one or more cells from a dormant state to a non-dormant state, according to the method of claim 1.

8. Receiving a second indicator, wherein the second indicator indicates that the group of the at least one second cell is in a dormant state, Based on the step of receiving the second indicator, further including the step of stopping the first inactivity timer and the DRX OnDuration timer, according to the method of claim 3.

9. Receiving a second indicator, wherein the second indicator indicates that the group of the at least one second cell is in a dormant state, Based on the step of receiving the second indicator, further including the step of ensuring that the DRX OnDuration timer is not started, according to the method of claim 3.

10. An apparatus comprising means for performing the method according to any one of claims 1 to 9.

11. A non-transitory computer-readable storage medium storing instructions, which, when executed by at least one processor, cause a computing system to perform the method according to any one of claims 1 to 9.

12. At least one processor, An apparatus comprising at least one memory including computer program code, wherein the at least one memory and the computer program code, when executed with the at least one processor, cause the apparatus to perform at least the method according to any one of claims 1 to 9. **Claim 13** A network node comprising a memory including computer-readable instructions, and at least one processor configured to read and execute the computer-readable instructions, wherein when the at least one processor reads and executes the computer-readable instructions, it performs a step of communicating with a first group of cells, a step of receiving a first indicator, the first indicator being for notifying the network node to enable scheduling with at least one second group of cells, a step of starting, based on the first indicator, a first inactivity timer associated with the at least one second group of cells, the first inactivity timer being shorter than a second inactivity timer associated with at least one of the first cell groups, and after the step of starting the first inactivity timer, a user equipment that performs a step of scheduling communication with the at least one second group of cells, wherein the first group of cells is a cell's primary discontinuous reception (P-DRX) group, wherein the at least one second group of cells is a cell's secondary discontinuous reception (S-DRX) group, and the step of scheduling the communication includes transmitting a command to one or more cells within the at least one second group of cells to switch the one or more cells from a dormant state to an active state. The user equipment is configured to use DRX mode operation via the group of the first cells or the group of the second cells. When the value of the physical downlink control channel (PDCCH) monitoring bit is 0, the user equipment does not start a drx-onDuration timer for the next long DRX cycle, and when the value of the PDCCH monitoring bit is 1, the user equipment starts the drx-onDuration timer for the next long DRX cycle.

14. The group of the first cells is a primary discontinuous reception (P-DRX) group of cells. The user equipment according to claim 13, wherein the at least one group of second cells is a secondary discontinuous reception (S-DRX) group of cells.

15. The user equipment according to claim 14, wherein the P-DRX group of cells transmits using a lower frequency range than the S-DRX group of cells.

16. The user equipment according to any one of claims 13 to 15, wherein the first inactivity timer is a DRX inactivity timer for a discontinuous reception (DRX) cycle of the S-DRX group of cells.

17. The S-DRX group includes a first physical downlink control channel (PDCCH) monitoring method in a first repeated discontinuous reception (DRX) cycle, and the first repeated DRX cycle includes a first uplink / downlink traffic period and a first OnDuration period. The P-DRX group includes a second physical downlink control channel (PDCCH) monitoring method in a second repeated discontinuous reception (DRX) cycle, and the second repeated DRX cycle includes a second uplink / downlink traffic period and a second OnDuration period. The user equipment according to claim 14, wherein the first downlink period and the first OnDuration period are each shorter than the second downlink period and the second OnDuration period, respectively.

18. The user equipment according to claim 17, wherein a first length of the first repetitive DRX cycle is the same as a second length of the second repetitive DRX cycle.

19. The user equipment according to claim 14, wherein the at least one processor further executes the step of scheduling the communication by executing a step of activating one or more cells of a group of the at least one second cell.

20. The user equipment according to claim 14, wherein the at least one processor further executes the step of scheduling the communication by executing a step of transmitting a command to one or more cells of a group of the at least one second cell, the one or more cells being switched from a dormant state to a non-dormant state.

21. The at least one processor is receiving a second indicator, the second indicator indicating that a group of the at least one second cell is in a dormant state, and further executing the step of stopping the first inactivity timer and the DRX OnDuration timer based on the step of receiving the second indicator. The user equipment according to claim 16.

22. The at least one processor is receiving a second indicator, the second indicator indicating that a group of the at least one second cell is in a dormant state, and The user equipment according to claim 16, further performing a step of ensuring that the DRX OnDuration timer is not started based on the step of receiving the second indicator.

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