CN116916422A

CN116916422A - Secondary cell discovery in energy-saving networks

Info

Publication number: CN116916422A
Application number: CN202310409381.8A
Authority: CN
Inventors: 胡亮; 裵正铉; 菲利普·琼·马克·米歇尔·萨托里
Original assignee: Samsung Electronics Co Ltd
Current assignee: Samsung Electronics Co Ltd
Priority date: 2022-04-14
Filing date: 2023-04-14
Publication date: 2023-10-20

Abstract

Disclosed are a system and method for performing communication by receiving a light Reference Signal (RS) on a carrier frequency in which a Synchronization Signal Block (SSB) is not detected; in response to receiving the light RS, obtaining light RS measurements and transmitting light RS measurement reports based on the light RS measurements; and starting to receive at least one SSB on the carrier frequency based on the light RS measurement report.

Description

Secondary cell discovery in energy-saving networks

Cross Reference to Related Applications

The present application claims priority from U.S. provisional application No. 63/331,224 filed on day 2022, month 4, and U.S. provisional application No. 63/408,084 filed on day 2022, month 9, and 19, the disclosures of each of which are incorporated by reference in their entireties as if fully set forth herein.

Technical Field

The present disclosure relates generally to wireless communication networks. More particularly, the subject matter disclosed herein relates to improvements in network side power conservation for wireless communication networks.

Background

Cellular systems are becoming more and more complex. Many cellular systems are designed with denser networks, greater operating bandwidth, and many antennas. Therefore, the power consumption of the cellular network increases and is a major part of the operator's operation costs (OPEX).

Although solutions have been proposed to reduce the power consumption of User Equipment (UE), the progress in reducing the power consumption at the network side is not continuous. In release 18 (Rel-18), an organization developing mobile telecommunication standards, the third generation partnership project (3 GPP), initiated research on reducing power consumption at the network level.

New Radio (NR) is a term used to refer to the next generation cellular wireless technology being developed by 3 GPP. NR is expected to become a key component of fifth generation (5G) mobile wireless technology and will provide a wide range of new capabilities and features such as higher data rates, lower latency and higher efficiency. NR will also be designed to support a wide range of use cases and applications, including enhanced mobile broadband, large-scale machine type communications, and ultra-reliable low-delay communications. Further, NR advances can be used to reduce power consumption on the network side.

In conventional NRs, a cell (e.g., a primary cell (PCell)) may continuously transmit a Synchronization Signal Block (SSB) signal and broadcast system information block 1 (SIB 1) information regardless of the traffic activity of the cell. In frequency range 1 (FR 1), the NR cell can provide relatively large coverage with little likelihood of no active devices in the cell, so that the reference signal can be transmitted continuously. However, in a densely deployed area with a large number of small cells on frequency range 2 (FR 2), some cells may not serve the UE. In such dense small area cell scenarios, selectively shutting down cells may provide significant benefits in terms of reduced network power consumption. The faster a cell opens or closes, the more efficiently it can track traffic dynamics and the greater the energy savings benefits. Thus, in order to reduce network power consumption, a physical signal and protocol procedure is needed to conveniently turn network nodes on and off as needed.

To overcome these problems, systems and methods for physical signal and protocol processes are described herein. For example, a light Reference Signal (RS) may be designed to enable a secondary cell (SCell) Discontinuous Transmission (DTX) mode. The DTX mode may be used to reduce the amount of power consumed by a UE or base station and improve the efficiency of the network. When a UE or base station is in DTX mode, it will only transmit data when it has data to transmit, and it will remain silent at other times.

When the SCell is in the power saving mode, it may transmit a light RS alone. In addition, the SCell may avoid transmitting a Synchronization Signal Block (SSB) and the light RS may avoid carrying a Master Information Block (MIB)/Physical Broadcast Channel (PBCH).

Further, the transmitted light RS may be used to detect scells in DTX off mode. Thus, the SCell may avoid sending light RSs for beam scanning or Radio Resource Management (RRM) measurements at the SCell in order to maximize SCell energy savings. In addition, the SCell may use a light RS for beam scanning of RRM measurements to further reduce network energy.

The above method improves on previous methods because energy is saved at the network side rather than at the client side. In particular, network energy may be saved by not sending SSBs, as light RS transmissions may be less frequent than SSB transmissions, thereby requiring less energy for transmission. In addition, network energy may be saved because beam scanning of RRM measurements may be performed without the need to repeatedly transmit RSs in different beam directions.

Disclosure of Invention

According to an aspect of the disclosure, a method for performing communication includes: receiving a light RS on a carrier frequency in which SSBs are not detected; in response to receiving the light RS, obtaining light RS measurements and transmitting light RS measurement reports based on the light RS measurements; and starting to receive at least one SSB on the carrier frequency based on the light RS measurement report.

According to another aspect of the disclosure, a UE is configured to perform communication. The UE includes a processor and memory storing program instructions that, when executed by the processor, configure the UE to receive a light RS on a carrier frequency in which SSBs are not detected, obtain a light RS measurement and send a light RS measurement report based on the light RS measurement in response to receiving the light RS, and begin receiving at least one SSB on the carrier frequency based on the light RS measurement report.

According to another aspect of the present disclosure, a method for activating an SCell includes: receiving an RS to initiate a wake-up signal (WUS) transmission on a carrier frequency in which SSBs are not detected, transmitting WUS to the SCell in response to receiving the RS; and starting to receive at least one SSB on the carrier frequency based on WUS measurements obtained in response to the transmission of WUS.

According to another aspect of the disclosure, a UE is configured to activate an SCell. The UE includes a processor and a memory storing program instructions that, when executed by the processor, configure the UE to receive an RS to initiate WUS transmission on a carrier frequency where SSBs are not detected, send WUS to the SCell in response to receiving the RS, and begin receiving at least one SSB on the carrier frequency based on WUS measurements obtained in response to the transmission of WUS.

Drawings

In the following sections, aspects of the subject matter disclosed herein will be described with reference to exemplary embodiments shown in the drawings, in which:

FIG. 1 illustrates an Ethernet (EN) -Dual Connection (DC) or NR-DC network configuration according to an embodiment;

fig. 2 shows an NR-Carrier Aggregation (CA) network configuration according to an embodiment;

fig. 3 shows a signal timing diagram of a Downlink (DL) based configuration according to an embodiment;

fig. 4 shows signaling exchange of DL-based configuration according to an embodiment;

fig. 5 shows a flow chart of a method for DL-based configuration according to an embodiment;

fig. 6 shows a signal timing diagram of a DL-based configuration according to an embodiment;

fig. 7 shows signaling exchange of DL-based configuration according to an embodiment;

Fig. 8 illustrates a conventional Synchronization Signal Block (SSB) signal and a light RS according to an embodiment;

fig. 9 shows signaling exchange of an Uplink (UL) based configuration according to an embodiment;

fig. 10 shows a flow chart of a method for UL-based configuration according to an embodiment;

fig. 11 shows signaling exchange of UL-based configuration according to an embodiment; and

fig. 12 is a block diagram of an electronic device in a network environment according to an embodiment.

Detailed Description

In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure. However, it will be understood by those skilled in the art that the disclosed aspects may be practiced without these specific details. In other instances, well-known methods, procedures, components, and circuits have not been described in detail so as not to obscure the subject matter disclosed herein.

Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment disclosed herein. Thus, appearances of the phrases "in one embodiment" or "in an embodiment" or "in accordance with an embodiment" (or other phrases having similar meaning) in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In this regard, as used herein, the word "exemplary" means "serving as an example, instance, or illustration. Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. Furthermore, depending on the context discussed herein, singular terms may include corresponding plural forms and plural terms may include corresponding singular forms. Similarly, the terms "two-dimensional," "predetermined," "pixel-specific," etc.) connected in hyphenation may sometimes be used interchangeably with corresponding non-hyphenated versions (e.g., "two-dimensional," "predetermined," "pixel-specific," etc.), as well as uppercase entries (e.g., "counter clock," "row select," "pixel output," etc.). ) May be used interchangeably with corresponding non-capitalized versions (e.g., "counter clock", "row select", "pixel output", etc.). Such occasional interchangeable uses should not be considered inconsistent with each other.

Furthermore, depending on the context discussed herein, singular terms may include corresponding plural forms and plural terms may include corresponding singular forms. It is also noted that the various figures (including component figures) shown and discussed herein are for illustrative purposes only and are not drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity. Furthermore, where considered appropriate, reference numerals have been repeated among the figures to indicate corresponding and/or analogous elements.

The terminology used herein is for the purpose of describing some example embodiments only and is not intended to be limiting of the claimed subject matter. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of 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.

It will be understood that when an element or layer is referred to as being "on," connected to, "or" coupled to "another element or layer, it can be directly on, connected to, or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being "directly on," "directly connected to" or "directly coupled to" another element or layer, there are no intervening elements or layers present. Like numbers refer to like elements throughout. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

The terms "first," "second," and the like, as used herein, are used as labels for their preceding nouns and do not imply any type of ordering (e.g., spatial, temporal, logical, etc.) unless explicitly so defined. Furthermore, the same reference numbers may be used throughout two or more drawings to refer to components, assemblies, blocks, circuits, units, or modules having the same or similar functionality. However, such usage is merely for simplicity of illustration and ease of discussion; it is not intended that the exact construction or architecture details of these components or units be the same in all embodiments, or that these commonly referenced parts/modules be the only way to implement some example embodiments disclosed herein.

Unless defined otherwise, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this subject matter belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

As used herein, the term "module" refers to any combination of software, firmware, and/or hardware configured to provide the functionality described herein in connection with the module. For example, software may be embodied as a software package, code, and/or instruction set or instructions, and the term "hardware" as used in any implementation described herein may include, for example, components, hardwired circuitry, programmable circuitry, state machine circuitry, and/or firmware that stores instructions executed by the programmable circuitry, alone or in any combination. These modules may be collectively or individually embodied as circuitry forming part of a larger system, such as, but not limited to, an Integrated Circuit (IC), a system-on-a-chip (SoC), a component, and the like.

A PCell may be a type of cell that provides coverage and capacity to 5G devices. It may be the primary source of communication for 5G devices and is responsible for sending data to and receiving data from the devices.

A cell may be a geographical area covered by a wireless network and it may be served by a base station, which is responsible for transmitting data to and receiving data from UEs within its coverage area.

In 5G networks, PCell may be used to provide coverage and capacity to 5G devices using a particular frequency band and Radio Access Technology (RAT). PCell may be a primary source of device communication and is responsible for transmitting data to and receiving data from devices.

In addition to the PCell, the 5G network may also include scells for providing additional coverage and capacity for devices. These cells may use different frequency bands and radio access technologies than the primary cell and they may be used to offload traffic from the primary cell or to provide coverage in areas where the primary cell has limited or no coverage. It can also be used to provide additional capacity for the network in areas with high demand. The secondary cell may use different frequency bands and radio access technologies than the primary cell and may be deployed in a variety of configurations depending on the needs of the network.

The SCell group (SCG) is a group of scells that are used to provide additional coverage and capacity for 5G devices. The SCell group (SCG) of a non-standalone (NSA) UE may be a NR cell group configured on the NR side. The PCell of the NSAUE may be a cell served by a master eNodeB (MeNB) and where the UE is camping. The PCell may initiate an initial access. The primary SCG cell (PSCell) of the NSAUE may be a PCell served by a secondary gcdeb (SgNB) and configured for the UE through a Radio Resource Control (RRC) message sent by the MeBN. The PSCell may remain active as long as the configuration is successful. The PSCell may be a cell that initiates initial access under SCG. The SCell of the NSA UE may be a cell configured for the UE by an RRC message sent by the MeNB. The SCell may provide additional radio resources to the UE.

Master Cell Group (MCG) and SCG are concepts in Dual Connectivity (DC). It can be appreciated that the MCG is located in a set of cells where the UE first initiates Random Access (RACH). If there is no double link, there is no concept of MCG and SCG. Alternatively, it can be appreciated that if no dual linking is performed, the cell group corresponds to MCG.

Fig. 1 shows an EN-DC or NR-DC network configuration according to an embodiment.

Referring to fig. 1, a macro cell 101 (PCell) may provide wide coverage in EN-DC or NR-DC network configurations. As shown by the pattern in fig. 1, various frequencies f are found in different SCell 102 areas _i May or may not be supported and used. Further, as shown by the pattern in fig. 1, some small cells (scells 102) may be in an active state and some small cells may be in a sleep state. More than one SCell 102 may be located within the coverage area of PCell 101. Further, the UE 103 is shown near the periphery of the SCell. Although the UE 103 is illustrated as a cellular telephone, other types of UEs may be used.

PCell may add/remove scells (excluding pscells) via RRC reconfiguration to provide additional capacity when the UE moves. In contrast to conventional NR SCell activation/deactivation, in a power saving network, a large number of scells (including PSCell) may be in "DTX mode", which means that they may only send light RSs instead of conventional RSs if they do not serve any UEs. This is illustrated in fig. 1, where an active small cell may transmit a legacy RS and a sleeping small cell may transmit a light RS.

Fig. 2 shows an NR-CA network configuration according to an embodiment.

In order for a UE to efficiently discover a PCell or SCell component carrier beam in a sleep mode of the PCell or SCell, a new UE UL WUS transmission may be used to wake up the PCell or SCell in the sleep mode. Additionally or alternatively, the UE may be configured to monitor light RSs and switch to monitoring on-demand SSB (on-demand SSB) once the cell is set to "DTX on" mode.

Referring to fig. 2, in an NR-CA network configuration, various carrier frequencies f _i May or may not be supported and used as shown by the pattern in fig. 2. Further, some cells may be in an active state and some cells may be in a sleep state, as shown by the pattern in fig. 2.

The NR-CA network configuration may focus on a standalone FR2 CA deployment scenario, also considering green domain deployment of release 18 (Rel-18) UEs (green field deployment). A potential difference between fig. 1 and 2 may be that the UE 201 cannot rely on a macro base station (PCell) to provide umbrella coverage to multiple smaller base stations (scells). In such a configuration, an embodiment of the SCell in DTX mode may not include a PSCell, which may be responsible for providing layer 3 (L3) handover when the UE moves.

To wake up the SCell 202, a downlink centric approach may be used, where the SCell sends a signal that may be used by the UE and reported to the gNB. The signal may be a light RS that is transmitted infrequently (e.g., less frequently than a conventional SSB due to a reduction in beam scanning). For example, a light RS may be sent once per second with a longer period than a conventional SSB burst.

Further, in order to wake up the SCell, a UL-centric approach may be used, where the SCell does not transmit any signal or only transmits a light RS, but performs measurements on WUS transmitted by the UE.

UL and DL solutions are not mutually exclusive and may be complementary, ideally deployed in combination. With embodiments of UL designs, the UE may send more signals, which increases UE power consumption. Therefore, if power consumption is to be reduced, it is preferable to deploy a DL-based solution. However, in some embodiments of DL design, when the SCell is in a "DTX off" state, the SCell may still send a light RS for the UE to maintain synchronization with the carrier or perform measurements (e.g., mobility related measurements). Without any active mobility handling, there may be a significant risk that the device may have left the coverage area of the SCell without the network knowing. In one case, the cell in sleep mode does not transmit DL RS, and only when WUS from the UE is detected, the cell switches from "DTX off" mode to "DTX on" mode, in which legacy RS (e.g., legacy SSB or SIB1 (for PCell) is transmitted). Thus, DL solutions may be preferred at low speeds, and UL solutions may be more suitable for high mobility.

When the cell is an SCell, it may only be accessible by Rel-18 UE, while the PCell may be accessible by Rel 17 (Rel-17) and Rel-18 UE to maintain the conventional mobility procedure.

For DL design, the light RS should be designed to consider a large number of scells in DTX mode when the UE is moving. Furthermore, the downlink design should allow the UE to adequately perform RRM measurements and identify the appropriate SCell.

In conventional NR, it is possible to switch off scells in the NR CA framework, where dormant bandwidth portions (BWP) are configured for UE power saving purposes. However, the SCell may still send the complete legacy SSB signal for RRM measurement and active state mobility control, which may consume a lot of power on the network side.

The present disclosure provides a design of SCell DTX mode, where light RSs are transmitted when no UE is served for network power saving. Some embodiments of the present disclosure may not have the transmission of legacy SSB signals on the SCell. Further, some embodiments may switch DTX mode on/off of scells in densely deployed areas more quickly (e.g., on/off at the slot level such that the transition of scells from "off" state to "on" state is fast enough for any dynamic traffic changes). Further, in some embodiments, the UE WUS may be transmitted by transmitting only a light RS to wake up a cell in a sleep mode for network power saving.

For UL design, when the UE transmits WUS to turn on/off scells, a large number of scells in DTX mode should be considered in WUS design when the UE moves. Furthermore, the uplink design should allow the UE to fully perform WUS transmissions and identify the appropriate SCell. Furthermore, UE transmissions may be sparse to reduce power consumption. Further, when the SCell is turned off, the UE may not have timing information of the SCell, and in case the UE does not have a PCell or PSCell connection, it may obtain the timing information by transmitting a light RS.

The function of the light RS may be to allow the UE to obtain synchronization and make basic measurements of neighbor SCell signal strengths so that the PCell may first select one or a subset of the scells downward to send a legacy SSB for beam scanning (e.g., during active state mobility). The light RS may be designed to transmit in one beam or multiple beam directions, but not necessarily in 64 beam directions in FR2 for beam scanning purposes. Then, for active mode mobility, beam management or beam scanning, the UE may make more accurate RRM measurements on legacy SSBs sent from only a subset of scells. In another embodiment, a light RS may also be used to completely replace the conventional SSB for beam scanning for RRM measurements. If a light RS power signal is used for beam scanning, the power consumption may be higher. Other solutions (e.g., UL-based solutions for WUS) may be used alone or in combination.

In some embodiments of the present disclosure, unlike legacy SSBs that allow all scells to always transmit for beam scanning, the light RS in combination with legacy SSB transmissions may save both SCell SSB transmission overhead and energy consumption.

Fig. 3 shows a signal timing diagram of a DL-based configuration according to an embodiment.

Referring to fig. 3, when the UE is not connected, the SCell frequently transmits a light RS (instead of the complete SSB of the SCell). In step 301, the ue detects a light RS transmitted by the SCell and determines a light RS measurement of the SCell. In step 302, the ue transmits a light RS measurement report to the PCell. If the measurements indicate that the UE may be adequately served by at least one SCell, the PCell may activate at least one SCell (or a set of scells), and may turn on legacy SSB transmissions (including beam scanning, if appropriate) for these scells by sending DCI to the UE in step 303. The PCell (e.g., the gNB) may configure the UE with a measurement configuration of at least one SCell, and may perform beam scanning using conventional procedures. In step 304, the ue calculates an on-demand SSB measurement. In step 305, the ue reports SSB measurements to the PCell using conventional procedures. The PCell may then ultimately decide which SCell and specific beam to activate for use by the UE. In step 306, the pcell transmits DCI for deactivating one or more scells.

Fig. 4 shows signaling exchange of DL-based configuration according to an embodiment.

Referring to fig. 4, one or more light RSs are transmitted from the SCell to the UE in step 401. Step 401 corresponds to step 301 in fig. 3. In step 402, the ue transmits a light RS measurement report to the PCell. Step 402 corresponds to step 302 in fig. 3. In step 403, the pcell transmits DCI to the UE to activate one or more scells by switching DTX to an "on" state. Step 403 corresponds to step 303 in fig. 3. In step 404a, the PCell sends an activation signal to the SCell. In step 404b, the SCell sends one or more on-demand SSB measurement signals to the UE. Step 404b corresponds to step 304 in fig. 3. In step 405, the ue sends an on-demand SSB measurement report to the PCell. Step 405 corresponds to step 305 in fig. 3. In step 406, the pcell transmits DCI to switch SCell DTX status to "off. Step 406 corresponds to step 306 in fig. 3.

Fig. 5 shows a flow chart of a method for DL-based configuration according to an embodiment.

The steps of fig. 5 may be performed by a UE, a processor, a controller, or another electronic device. Furthermore, some steps may be performed concurrently or in a different order than shown.

Referring to fig. 5, in step 501, an SCell light RS configuration is received from a PCell. For example, the UE may move into coverage of one or more scells while maintaining an RRC connected state with a PCell (macro cell). The UE may be located in an area where there are one or more scells in DTX "on" mode. To be able to detect scells, the UE may receive a configuration (which is expected to be detectable for a given carrier frequency) from a network with a light RS configuration. The UE may not have previously detected SSB for the given carrier frequency. The configuration may be provided by RRC signaling (dedicated or common) and may include one or more of the following: the transmission period of the light RS, the frequency resource of the light RS transmitted, the time interval at which the UE is expected to receive the light RS, an index of the light RS uniquely identifying the light RS, and the SSB quasi co-location (QCL) type D corresponding to the light RS. The gNB may update the light RS configuration by adding/removing light RSs to be monitored and update the SSB for the UE to monitor.

In step 502, a measurement of the light RS is performed. For example, the UE may start measuring light RSs (RS received power (RSRP) or RS strength indicator (RSSI)) of all neighboring scells according to a measurement configuration previously received from the PCell. The measurement may begin when the UE receives a light RS configuration. In some embodiments, the light RS measurement may be activated/deactivated by a specific trigger (e.g., a Medium Access Control (MAC) Control Element (CE) or DCI). The light RS measurement may include a coarse acquisition of a cell that is timed in a DTX off state, and RSRP measurement based on Resource Elements (REs) occupied by the light RS.

In step 503, the light RS measurement is reported to the PCell. For example, the UE reports SCell measurements to the PCell. The measurement results may be reported via L1, configuration grant type 1 (CG 1), and/or RRC signaling.

Based on a measurement report configuration received from the PCell prior to measurement, the L1 measurement report may include enhanced Channel State Information (CSI) -RS reports and/or new light RS reports for Multiple Transmission and Reception Point (MTRP) transmission point selection. The L1 measurement report may be particularly useful if it is desired to wake up the SCell quickly.

The CG1 measurement report may include that when a light RS configuration is received, the UE may be configured for the associated set of resources (in the same or a different message) for CG 1. The UE may use CG1 to report measurements performed on a light RS (or multiple light RSs if several measurements are bundled together). The UE may be configured to report the measurement only when the measurement is above a power threshold. The UE may not even report power or quality measurements, but simply send an indication that the SCell should be woken up.

If the wake-up SCell is not time sensitive, the light RS measurement may be reported through RRC signaling. RRC signaling measurement reporting occurs only when the signal is above a threshold.

In step 504, the ue determines whether an indication that the SCell is awake has been received. The PCell (gNB) may send a message to the UE to indicate that the SCell has been awakened.

Activation of the legacy SSB transmission may be accomplished through legacy SCell activation using MAC-CE. This may be done using a MAC-CE indicating that a legacy SSB is active, and the light RS monitoring associated with that SSB may be automatically deactivated (implicit indication). Additionally or alternatively, the MAC-CE may include additional fields to carry information (explicit indication) about legacy SSB activation.

SCell may be activated or deactivated with new DCI. In some cases, it may be desirable to wake up the SCell quickly. In this case, the solution may be to send physical layer signaling because it has low latency. This may be enhanced by the design of new DCI, which will be described later in this disclosure.

RRC signaling can also be used by sending a new light RS configuration. When a new light RS configuration is received, the UE may assume that there are no more light RSs indicating that the corresponding SCell has been turned on.

In step 505, if an indication that the SCell is awake has been received ("yes" in step 504), monitoring of the light RS of the SCell is stopped and SSB is monitored instead. The UE may receive SSBs of the carrier frequency and perform conventional SSB-based RRM measurements and may cease monitoring the associated light RSs. If the UE does not receive the wakened indication, the UE may continue to monitor for light RSs. The UE may report SSB-based measurements and/or light RS-based measurements to a PSCell (gNB). Optionally, the gNB can also send an indication of SCell off. This may not be necessary because most of the time, when there is no traffic in the cell, the network may decide to switch to another SCell. In addition, the signaling described previously indicating "waken" may also be used to indicate "off". Upon receiving such a message, the UE may then switch from SSB to light RS monitoring.

In step 506, if no indication is received that the SCell is awake (no in step 504), light RS monitoring continues. In this case, the UE may not switch to the legacy SSB reception after receiving the DCI or MAC CE. The UE may continuously receive light RSs from the SCell to perform RRM, radio Link Monitoring (RLM), and/or Bidirectional Forwarding Detection (BFD) measurements, but with a different light RS configuration than the first phase cell discovery. For example, different light RS configurations may enable scells and/or UEs to perform beam management procedures, where light RSs are repeatedly transmitted in different beams.

In step 507, the ue determines whether an indication of SCell off is received. If an indication of SCell off is received (yes at step 507), the ue switches to light RS monitoring at step 508. If no indication of SCell off is received (no at step 507), the UE continues SSB monitoring.

As described above, a quick decision to turn on the SCell may be appropriate. To perform such a fast decision, the gNB may use aperiodic light RSs. The presence of aperiodic light RSs may utilize new DCI or new DCI fields. This field may be configured if the UE indicates that it has the capability to handle light RSs or aperiodic light RSs. Operations for aperiodic CSI reporting may be reused to a large extent. In particular, legacy Access Point (AP) CSI-RS reporting configurations can be extended with a new measurement object "light RS" in CSI-Report config and NZP-CSI-RS-resource set.

Fig. 6 shows a signal timing diagram of a DL-based configuration according to an embodiment.

In step 601, the scell sends a light RS measurement to the UE. The complete set of light RSs may be scanned in the cell in all possible beam directions to allow the UE to detect possible scells.

In step 602, the ue transmits RACH to the SCell. The UE may send RACH message 1 to the SCell on the detected beam of the light RS.

In step 603, the scell sends the on-demand complete SSB to the UE on the RACH beam. The full version of SSB may be sent on the beam where the UE sends RACH.

In step 604, the ue transmits a legacy random access to the SCell. The UE may perform legacy random access on the SCell.

Fig. 7 shows signaling exchange of DL-based configuration according to an embodiment.

Referring to fig. 7, one or more light RSs are transmitted from the SCell to the UE to perform beam scanning in step 701. Step 701 corresponds to step 601 in fig. 6. The UE may move into coverage of one or more scells while still in RRC connected state with the PCell (macro cell). The UE may be located in an area where there are one or more scells in DTX "on" mode. To detect the SCell, the UE may receive a configuration from the network with a light RS configuration that it is expected to be able to detect. The configuration may be provided by RRC signaling (dedicated or common) and may include a transmission period and an RS beam scan pattern of the light RSs, frequency resources in which a set of light RSs are transmitted, a time interval in which the UE is expected to receive light RSs, and/or a set of light RS indices that uniquely identify each light RS beam.

The UE may start measuring the light RS beams (RSRP or RSSI) of all neighboring scells according to the measurement configuration received from the PCell. The measurement may begin when the UE receives a light RS configuration. The light RS measurement may be activated or deactivated by a specific trigger (e.g., MAC CE or DCI). The light RS measurement may include a coarse acquisition of a cell in a DTX off state, and RSRP measurement based on REs occupied by the light RS.

The UE may measure the light RS beam in all possible directions and detect the best light RS beam with the best measured RSRP value (e.g., the light RS beam with the highest signal strength or least amount of interference).

In step 702, the ue transmits RACH on the detected beam. Step 702 corresponds to step 602 in fig. 6. The UE may send RACH message 1 to the SCell on the detected beam of the light RS. The SCell may wake up by receiving a RACH transmission from the UE.

In step 703, the on-demand SSB is sent to the UE on the beam detected by the UE. Step 703 corresponds to step 603 in fig. 6. A full version of the legacy SSB may be sent by the SCell only on the beam on which the UE sends RACH. In this case, the energy of the SCell may be reduced by avoiding beam scanning.

In step 704, a legacy random access signal is transmitted from the UE to the SCell. Step 704 corresponds to step 604 in fig. 6. The UE may perform a legacy random access procedure on the SCell and thereafter perform legacy UL and DL transmissions.

In step 705, a legacy random access signal is transmitted from the SCell to the UE.

Fig. 8 illustrates a conventional SSB signal and a light RS according to an embodiment.

Referring to fig. 8, the light RS may include only a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS), and not a PBCH, which may provide frequency and time synchronization to the SCell. The light RS may not allow the SCell to perform a full beam scan and only one or a subset of the beams may be used to transmit the light RS for the UE to find the SCell in DTX mode. At this stage, the UE may identify a subset of potentially good cells (e.g., with high signal strength) before performing the legacy RRM measurements. PSS and SSS may occupy different symbols than their locations in a conventional SSB.

The light RS may also include CSI-RS that is optional for transmission point (TRP) selection in the MTRP SCell. Additionally or alternatively, the light RSs may comprise CSI-RS only, PSS only, or SSS only. Furthermore, the light RS may be composed of a combination of other existing RSs (e.g., PTRS or PRS), or may even be a new reference signal that has not been defined by 3GPP in Rel-18.

The TRP identification (TPID) may include one or more of the following: physical Cell ID (PCID) (the UE may assume that the CSI-RS of the TRP and the PSS/SSS corresponding to the PCID are quasi co-sited), CSI-RS scrambling ID, CSI-RS resource indicator, CSI-RS RE configuration, CSI-RS slot offset relative to the SSS in the light RS.

The TPID may also be provided via a pre-configured TCI (transmission configuration indication, TCI) state combined with the SCell PCID detected by decoding PSS and SSS, where each TRP may be mapped to one TCI state with one CSI-RS resource ID. The TRP identification may be reported with a corresponding CSI-RS based measurement report.

In addition, the light RS may be composed of an existing SSB in which PBCH and PBCH demodulation reference signals (DMRS) have been removed. To achieve backward compatibility, one option may be to not transmit PBCH data REs while still transmitting PSS, SSS and PBCH DMRS that follow the legacy SSB.

The light RS may be a single legacy SSB signaling. In this case, by reusing the legacy SSB signal design, the SCell may alternate between transmitting a single SSB for SCell detection and repeatedly transmitting SSB (triggered by DCI or MAC CE) for legacy beam scanning for RRM measurements. The UE may be configured by the PCell with two different measurement configurations for SCell detection and legacy RRM measurements.

Furthermore, the legacy UE may detect the PSS, but it may not be able to decode the light RS. Legacy UEs may attempt to detect SSS, but may fail due to different physical mappings. This may introduce considerable delay and problems for legacy UEs. To avoid this, one solution could be to assign a special sync grating position for the light RS, where Rel-18 UE would decode the light RS. Furthermore, some aspects of PSS may be altered to avoid detection by legacy UEs. For example, a particular Zadoff-Chu (ZC) or m-sequence may be used (or reserved) for PSS to transmit light RS. The PSS sequence may be generated by cyclically shifting an m-sequence of a basic length 127 by 0, 43 or 86 steps to generate a desired (e.g., 1 out of 3) m-sequence of the PSS sequence.

For light RSs, the set of light PSS sequences may be extended by a set of different cyclic shifts of m-sequences in the legacy PSS, except for steps 0, 43 and 86, so that legacy UEs will not detect those light PSS sequences, thereby avoiding confusion during blind cell search. For example, to avoid false detection in noisy environments, a set of light RS-specific PSS sequences may have cyclic shifts separated by 43 steps from the legacy PSS sequences and separated by 43 steps from each other. In another example, shift 22 may use steps 22, 65, and 108 since steps 0, 43, and 86 are conventionally used. Other solutions to ensure that the light RS is different from the PSS (e.g., using sequences other than ZCs, "scrambling" the PSS with another sequence) may also be used alone or in combination with one or more of the disclosed solutions.

Further, if the UE is able to detect a Positioning Reference Signal (PRS), the UE may be able to detect the PRS as a light RS.

The PCell may use a light RS to indicate the physical resource location of the PRS set in the carrier on which the SCell is operating. The signaling may be similar to that done for OTDOA-neighbor cellinfoelement (e.g., indicating the expected arrival time (field equivalent to expectedRSTD) and time window (field equivalent to expectedRSTD-uncrtantity)). Each PRS may be associated with a unique index.

The UE may report to the gNB on the PCell which PRSs are received above a certain threshold.

Thus, solutions using PRS or PRS-like sequences may also be used, wherein PRS or PRS-like sequences serve as WUS. More specifically, legacy PRSs may be configured directly to UEs via a location server using a gNB as a relay. In some embodiments, the PCell may pre-configure the UE with a set of PRSs in a particular physical resource, each PRS corresponding to an SCell and/or TRP. The Information Element (IE) may be similar to an IE of OTDOA-referenceCellInfo or OTDOA-OTDOA-neighbor CellInfoList. For example, the IE may be configured by the PCell to the UE via RRC signaling based on the following sequence:

/>

in addition, DCI may also be configured to improve network power saving. An SCell DTX on/off DCI indication may be sent to the UE on the PCell. The DCI may be a group common DCI in which each block of the DCI corresponds to one UE. In each block, the set of scells in DTX "on" or "off state may be mapped via a" 1 "or" 0 "bitmap, respectively. The bitmap of the SCell set in the DCI may correspond to the SCell set on which the UE performs the light RS measurement report. The DCI may also include a set of TRPs for a given SCell in a DTX "on" or "off state. An example of a bit map of the UE is shown in table 1 below.

TABLE 1

	SCell1	SCell2	SCell3	SCell4	SCell5
						TRP1	1	1	0	0	0
TRP2	1	1	0	0	0
						TRP3	0	1	1	0	0
TRP4	0	1	0	0	0

Wherein "0" represents a DTX "off" state and "1" represents a DTX "on" state.

The UE may measure RSRP and RSSI of the light RS when the SCell is in DTX "off" state. Before the UE performs the measurement, the UE may be configured with a measurement configuration via the PCell.

The signaling of the light RS measurement timing configuration (LMTC) (for frequency) may include LMTC period and offset, light RS occasion duration (common to all scells for a given frequency), measurement bandwidth, a set of TCI states for each light RS, neighbor cell lists (PCIDs), and neighbor TRP lists including TRP identification information for each TRP and all CSI-RS parameters for TRP identification.

UL-based methods may be used that rely on the UE sending WUS to the SCell. The SCell may monitor the WUS and determine if it should wake up. The UE may more flexibly determine when to transmit WUS and may transmit WUS only when needed, which may utilize higher UE transmit power because the UE may transmit light RSs.

Fig. 9 illustrates signaling exchange of UL-based configuration according to an embodiment.

Referring to fig. 9, in step 901, a light RS is transmitted from an SCell and received by a UE. The light RS may be a synchronization signal. The UE may have coarse timing from the SCell. Thus, the UE may obtain synchronization information from the SCell. This may be achieved by having a light synchronization signal, similar to a light RS, sent periodically by the SCell. The SCell may not transmit the SSB and the period of the synchronization signal may be large. Even for unsynchronized networks, the UE may not receive a light RS. For example, the PCell may indicate an offset value between its timing and SCell timing, and the UE may transmit RACH to the SCell.

In step 902, the PCell sends RRC to the UE. The RRC may configure a specific WUS for the UE. For example, WUS may be a specific non-contention msg1 (e.g., a specific preamble combined with a dedicated RO resource). There may be multiple WUSs with different preamble and RO combinations and sent by the UE with different UL beams in all possible beam directions to wake up the candidate SCell. WUS may also be UL Sounding Reference Signals (SRS). There may be a predefined light_rs-WUS resource map, similar to PRACH-SSB association. In this case, the UE may decode the DL light RS beam set and transmit WUS with the UL beam quasi co-located with the light RS beam of the strongest received RSRP in the corresponding WUS occasion of the mapping. Thus, similar to the PRACH to SBB mapping, the SCell may then determine the best WUS receive beam based on the received signal of the WUS occasion.

In addition, other signals may be used instead of RRC WUS. For example, WUS may be SRS (possibly with new SRS usage not currently defined by 3GPP in Rel-18), or newly defined RS. Similarly configured parameters may include time-frequency resources (aperiodic transmissions (similar to CSI-RS) may also be used) and/or resource indexes for transmitting RSs.

In step 903, the pcell transmits DCI to the UE. The DCI transmitted to the UE in step 903 may activate the UE. The PCell may configure "always allowed" WUS for the UE through RRC, where the network configuration WUS occasions are not frequent enough to periodically soft wake up for UE WUS transmissions via MAC CEs.

In addition, other signals may be used instead of RRC WUS (e.g., SRS (possibly defining new SRS uses), or newly defined RS). Similarly configured parameters may include time-frequency resources (aperiodic transmissions (similar to CSI-RS) may also be used) and/or resource indexes for transmitting RSs.

In step 904, the ue transmits at least one WUS to the SCell. The UE may send one or more WUS in a set of UL beams based on previous DL light RS measurements from the SCell or set of TRPs. For example, the UE may transmit WUS with one or more UL beams quasi co-located with the received DL light RS beam set with the strongest received RSRP in type D. For a potential SCell, to detect WUS from a UE, the SCell may perform the detection without any best tuning of the received beam or determine whether WUS reception with that beam corresponds to the selected transmit beam of WUS in a given WUS occasion (e.g., specific frequency and time resources) according to a predefined light RS-WUS resource mapping (similar to PRACH-SSB association). In the latter case (if it is determined whether WUS reception with that beam corresponds to a selected transmit beam of WUS in a given WUS occasion), the UE may decode the DL light RS beam set and then transmit WUS in a mapped WUS occasion with the UL beam quasi co-located with the light RS beam of the strongest received RSRP in type D. The SCell may then determine the WUS receive beam based on the signals received at the WUS occasion. SCell WUS detection may be disposable and may not have subsequent UL reception until the SCell is activated and selected as a serving SCell to perform legacy procedures. Thus, SCell blind detection of WUS may be an alternative. The latter approach may have better performance because it provides the gNB information about which receive beam to use, and thus it may provide better received signal quality.

In addition, the transmission of the WUS of the UE may include a light RS configuration with periods and resources for the UE to transmit light RSs. After receiving the light RS configuration, the UE may perform transmission on each transmission opportunity indicated by the light RS (possibly after activation or deactivation, similar to a semi-persistent scheduling (SPS) configuration).

The gNB may activate WUS transmission using DCI or MAC CE. The activation may be for one specific WUS corresponding to a specific SCell.

The UE may independently decide whether to transmit WUS. For example, if a signal from the SCell is received with sufficient power or quality, the UE may decide not to transmit WUS.

In step 905, the SCell sends an SCell measurement report to the PCell. In step 906, the pcell transmits DCI to the UE. The DCI may activate a DTX "on" state. In step 907, the pcell sends an SCell activation signal to the SCell. The SCell may be configured to monitor UL WUS for a predefined period of time.

In response to receiving an indication that the SCell is activated (e.g., in response to receiving DCI in step 906), the UE may stop sending WUS if the UE wakes up.

In step 908, the scell sends one or more on-demand SSB measurement signals to the UE. In step 909, the ue sends an on-demand SSB measurement report to the PCell. In step 910, the pcell transmits DCI to switch SCell DTX status to "off.

Fig. 10 shows a flow chart of a method for UL-based configuration according to an embodiment.

The steps of fig. 10 may be performed by a UE, a processor, a controller, or another electronic device.

Referring to fig. 10, in step 1001, an RS (or light RS) and WUS configuration are received by a UE. The RS may be transmitted from the SCell and the RRC may be transmitted from the PCell.

In step 1002, the ue receives a light synchronization signal from the SCell. The light synchronization signal may be a signal that initiates WUS transmission by the UE in an inactive state on a carrier frequency where SSB is not detected. In step 1003, the ue transmits WUS (or light WUS). Transmitting a light WUS may cause the SCell to obtain measurements. In step 1004, the ue determines whether an indication that the SCell is awake has been received. For example, if the obtained measurement is greater than a predetermined value (e.g., RSRP threshold), the indication may be received. If the indication is received, the ue stops transmitting WUS in step 1005. In this case, the UE may receive a signal indicating to stop transmitting WUS from the PCell. Further, the UE may receive at least one SSB on a carrier frequency based on the measurement. On the other hand, if the indication is not received, the ue continues to transmit WUS in step 1006.

After stopping the transmission of WUS in step 1005, the ue determines whether an indication that the SCell is asleep is received in step 1007. If the indication is received, the ue resumes transmitting WUS in step 1008. If the indication is not received, the UE does not transmit the light WUS.

Green network deployment is a type of network deployment in which a new network is built from scratch in areas where there was no network infrastructure before. Greenfield deployments are typically used when networks are established at new locations, or when there is a high demand for increased speed and capacity. They provide the opportunity to design and build networks from scratch, while taking into account specific requirements and demands.

The difference between the green network deployment and other network deployment scenarios is that PCell and PSCell may also support DTX mode in the green network, with light RSs sent in the deactivated mode. Thus, all UEs on the network may be Rel-18 capable UEs. Furthermore, backward compatibility supporting Rel-17 UE may or may not be supported by the network.

Fig. 11 illustrates signaling exchange of UL-based configuration according to an embodiment.

The solution disclosed in fig. 11 may be used for greenfield Rel-18 deployment scenarios with L3 handover capability.

Referring to fig. 11, in step 1101, one or more light RSs are transmitted from the SCell to the UE. In step 1102, the serving PCell sends an RRC signal to the UE. The RRC signal may configure a specific WUS for the UE. For example, WUS may be a specific non-contention msg1 (e.g., a specific preamble combined with a dedicated RO resource). There may be multiple WUSs, each with a different preamble and RO combination and transmitted by the UE with a different UL beam in order to wake up candidate neighbor PCell in all possible beam directions. WUS may also be UL SRS. Similar to PRACH-SSB association, there may be a predefined light_rs-WUS resource mapping. In this case, the UE may decode the DL light RS beam set and transmit WUS with the UL beam quasi co-located with the light RS beam of the received strongest received RSRP in type D in the mapped corresponding WUS occasion. Thus, similar to the PRACH-to-SBB mapping, the neighboring PCell may then determine the best WUS receive beam based on the received signals in the WUS occasions used.

In step 1103, the PCell transmits DCI to the UE. The serving PCell may activate the UE via DCI to transmit WUS. The serving PCell may use RRC to configure "always allowed" WUS for the UE, where the network configuration WUS occasions are sufficiently infrequent that it enables soft wake-up of UE WUS transmissions periodically via MAC CEs.

In step 1104, the ue transmits at least one WUS measurement signal. The UE may send one or more WUS in the UL beam set based on previous DL light RS measurements from the neighboring PCell or TRP set. For example, the UE may transmit WUS with one or more UL beams quasi co-located with the received DL light RS beam set with the strongest received RSRP in type D. For detecting potential candidate PCell for WUS from a UE, it may either blindly detect without any optimal tuning of the received beam, or determine whether WUS reception with that beam corresponds to the selected WUS transmit beam at a given WUS occasion (e.g., specific frequency and time resources) according to a predefined light RS-WUS resource mapping (similar to PRACH-SSB association). In the latter case (if WUS reception with a beam corresponds to the selected WUS transmit beam at a given WUS occasion (e.g. a specific frequency and time resource), the UE may decode the DL light RS beam set and transmit WUS with a UL beam quasi-co-located with the light RS beam of the received strongest received RSRP in type D in the mapped WUS occasion. Thus, the candidate PCell may then determine WUS receive beams based on the signals received in the WUS occasions. For the candidate PCell, WUS detection may be one-time and no subsequent UL reception until the candidate PCell becomes active and is selected as the serving PCell to perform legacy procedures. The latter approach may provide better received signal quality because it provides the gNB information about which received beam is used, and thus it may provide better received signal quality.

In step 1105, the ue receives DCI from the PCell. At this step, the UE may receive a new DCI or MAC CE from the serving PCell for activating on-demand legacy SSB reception. The serving PCell may determine a subset of neighbor PCell that may be candidate serving cells for the UE from among all neighbor PCell based on WUS measurements of the neighbor PCell.

In step 1106, the on-demand SSB is sent from the neighboring PCell to the UE. The UE may perform conventional SSB-based RRM measurements and perform DL or UL data transmission until the UE receives new DCI or MAC CE from the serving PCell for activating the light RS transmission again.

In step 1107, the serving cell receives the on-demand SSB measurements and reports. In step 1108, the scell UE sends a legacy L3 handover procedure signal to the UE. In step 1109, the scell transmits DCI to the UE activating the neighbor PCell DTX "off" state.

Further, after receiving the DCI or MAC CE, the UE may not switch to legacy SSB reception. The UE may continue to receive light RSs from the neighboring PCell to perform RRM measurements, but with a different light RS configuration than the first stage cell discovery. For example, different light RS configurations may enable neighboring pcells and/or UEs to perform beam scanning procedures in which light RSs are repeatedly transmitted in different beams.

Fig. 12 is a block diagram of an electronic device in a network environment 1200 according to an embodiment.

Referring to fig. 12, an electronic device 1201 in a network environment 1200 may communicate with an electronic device 1202 via a first network 1298 (e.g., a short-range wireless communication network) or with the electronic device 1204 or server 1208 via a second network 1299 (e.g., a long-range wireless communication network). The electronic device 1201 may communicate with the electronic device 1204 via a server 1208. The electronic device 1201 may include a processor 1220, memory 1230, input device 1250, sound output device 1255, display device 1260, audio module 1270, sensor module 1276, interface 1277, haptic module 1279, camera module 1280, power management module 1288, battery 1289, communication module 1290, subscriber Identity Module (SIM) 1296, or antenna module 1294. In one embodiment, at least one of the components (e.g., the display device 1260 or the camera module 1280) may be omitted from the electronic device 1201, or one or more other components may be added to the electronic device 1201. Some of the components may be implemented as a single Integrated Circuit (IC). For example, the sensor module 1276 (e.g., a fingerprint sensor, iris sensor, or illuminance sensor) may be embedded in the display device 1260 (e.g., a display).

Processor 1220 may run software (e.g., program 1240) to control at least one other component (e.g., a hardware component or a software component) of electronic device 1201 coupled to processor 1220 and may perform various data processing or calculations.

As at least part of the data processing or calculation, processor 1220 may load commands or data received from another component (e.g., sensor module 1276 or communication module 1290) into volatile memory 1232, process commands or data stored in volatile memory 1232, and store the resulting data in non-volatile memory 1234. Processor 1220 can include a main processor 1221 (e.g., a Central Processing Unit (CPU) or an Application Processor (AP)) and an auxiliary processor 1223 (e.g., a Graphics Processing Unit (GPU), an Image Signal Processor (ISP), a sensor hub processor, or a Communication Processor (CP)) that is operatively independent of or in conjunction with main processor 1221. Additionally or alternatively, the secondary processor 1223 may be adapted to consume less power than the primary processor 1221, or to perform certain functions. The secondary processor 1223 may be implemented separately from the primary processor 1221 or as part of the primary processor 1221.

The auxiliary processor 1223 may control at least some of the functions or states associated with at least one of the components of the electronic device 1201 (e.g., the display device 1260, the sensor module 1276, or the communication module 1290) when the main processor 1221 is in an inactive (e.g., sleep) state, or the auxiliary processor 1223 may control at least some of the functions or states associated with at least one of the components of the electronic device 1201 (e.g., the display device 1260, the sensor module 1276, or the communication module 1290) with the main processor 1221 when the main processor 1221 is in an active state (e.g., running an application). The auxiliary processor 1223 (e.g., an image signal processor or a communication processor) may be implemented as part of another component (e.g., a camera module 1280 or a communication module 1290) functionally related to the auxiliary processor 1223.

The memory 1230 may store various data used by at least one component of the electronic device 1201 (e.g., the processor 1220 or the sensor module 1276). The various data may include, for example, software (e.g., program 1240) and input or output data for commands associated therewith. Memory 1230 may include volatile memory 1232 or nonvolatile memory 1234.

The program 1240 may be stored as software in the memory 1230 and the program 1240 may include, for example, an Operating System (OS) 1242, middleware 1244, or applications 1246.

The input device 1250 may receive commands or data from outside the electronic device 1201 (e.g., a user) to be used by another component of the electronic device 1201 (e.g., the processor 1220). Input device 1250 may include, for example, a microphone, a mouse, a keyboard.

The sound output device 1255 may output a sound signal to the outside of the electronic device 1201. The sound output device 1255 may include, for example, a speaker or a receiver. Speakers may be used for general purposes such as playing multimedia or playing a album and receivers may be used for incoming calls. The receiver may be implemented separate from the speaker or as part of the speaker.

The display device 1260 may provide information visually to an exterior (e.g., a user) of the electronic device 1201. The display device 1260 may include, for example, a display, a holographic device, or a projector, and control circuitry for controlling a corresponding one of the display, holographic device, and projector. The display device 1260 may include touch circuitry adapted to detect touches or sensor circuitry (e.g., pressure sensors) adapted to measure the strength of forces caused by touches.

The audio module 1270 may convert sound to electrical signals and vice versa. The audio module 1270 may obtain sound via the input device 1250 or output sound via the sound output device 1255 or headphones of an external electronic device 1202 that is directly (e.g., wired) or wirelessly connected to the electronic device 1201.

The sensor module 1276 may detect an operational state (e.g., power or temperature) of the electronic device 1201 or an environmental state (e.g., a state of a user) external to the electronic device 1201 and then generate an electrical signal or data value corresponding to the detected state. The sensor module 1276 may include, for example, a gesture sensor, a gyroscope sensor, an atmospheric pressure sensor, a magnetic sensor, an acceleration sensor, a grip sensor, a proximity sensor, a color sensor, an Infrared (IR) sensor, a biometric sensor, a temperature sensor, a humidity sensor, or an illuminance sensor.

The interface 1277 may support one or more specific protocols that will be used to connect the electronic device 1201 with the external electronic device 1202 directly (e.g., wired) or wirelessly. Interface 1277 may comprise, for example, a High Definition Multimedia Interface (HDMI), a Universal Serial Bus (USB) interface, a Secure Digital (SD) card interface, or an audio interface.

The connection end 1278 may include a connector via which the electronic device 1201 may be physically connected with the external electronic device 1202. The connection end 1278 may include, for example, an HDMI connector, a USB connector, an SD card connector, or an audio connector (e.g., a headphone connector).

The haptic module 1279 may convert an electrical signal into mechanical stimulus (e.g., vibration or motion) or electrical stimulus that can be recognized by the user via his sense of touch or kinesthetic sense. The haptic module 1279 may include, for example, a motor, a piezoelectric element, or an electro-stimulator.

The camera module 1280 may capture still images or moving images. Camera module 1280 may include one or more lenses, image sensors, image signal processors, or flash. Power management module 1288 may manage power to electronic device 1201. Power management module 1288 may be implemented as at least part of, for example, a Power Management Integrated Circuit (PMIC).

The battery 1289 may power at least one component of the electronic device 1201. The battery 1289 may include, for example, a primary non-rechargeable battery, a secondary rechargeable battery, or a fuel cell.

The communication module 1290 can support establishing a direct (e.g., wired) communication channel or a wireless communication channel between the electronic device 1201 and an external electronic device (e.g., electronic device 1202, electronic device 1204, or server 1208) and performing communication via the established communication channel. Communication module 1290 may include one or more communication processors capable of operating independently of processor 1220 (e.g., an AP) and supporting direct (e.g., wired) or wireless communication. The communication modules 1290 may include a wireless communication module 1292 (e.g., a cellular communication module, a short-range wireless communication module, or a Global Navigation Satellite System (GNSS) communication module) or a wired communication module 1294 (e.g., a Local Area Network (LAN) communication module or a Power Line Communication (PLC) module). A corresponding one of these communication modules may communicate with external electronic devices via a first network 1298 (e.g., a short-range communication network such as bluetooth, wireless fidelity (Wi-Fi) direct, or infrared data association standard (IrDA)) or a second network 1299 (e.g., a long-range communication network such as a cellular network, the internet, or a computer network (e.g., a LAN or Wide Area Network (WAN)). These various types of communication modules may be implemented as a single component (e.g., a single IC), or may be implemented as multiple components (e.g., multiple ICs) separate from one another. The wireless communication module 1292 can identify and authenticate the electronic device 1201 in a communication network, such as the first network 1298 or the second network 1299, using user information (e.g., international Mobile Subscriber Identity (IMSI)) stored in the user identification module 1296.

The antenna module 1297 may transmit signals or power to or receive signals or power from outside of the electronic device 1201 (e.g., an external electronic device). The antenna module 1297 may include one or more antennas and, as such, at least one antenna suitable for a communication scheme used in a communication network (such as the first network 1298 or the second network 1299) may be selected by, for example, the communication module 1290. Signals or power may then be transmitted or received between the communication module 1290 and the external electronic device via the selected at least one antenna.

Commands or data may be sent or received between the electronic device 1201 and the external electronic device 1204 via a server 1208 connected to the second network 1299. The electronic device 1202 and the electronic device 1204 may each be the same type of device as the electronic device 1201, or different types of devices from the electronic device 1201. All or some of the operations to be performed at the electronic device 1201 may be performed at one or more of the external electronic device 1202, the external electronic device 1204, or the server 1208. For example, if the electronic device 1201 should automatically perform a function or service or should perform a function or service in response to a request from a user or another device, the electronic device 1201 may request the one or more external electronic devices to perform at least part of the function or service instead of or in addition to the function or service, or the electronic device 1201 may request the one or more external electronic devices to perform at least part of the function or service. The one or more external electronic devices that received the request may perform the requested at least part of the function or service or perform another function or another service related to the request and transmit the result of the performing to the electronic device 1201. The electronic device 1201 may provide the results as at least a partial reply to the request with or without further processing of the results. For this purpose, cloud computing technology, distributed computing technology, or client-server computing technology, for example, may be used.

Embodiments of the subject matter and the operations described in this specification can be implemented in digital electronic circuitry, or in computer software, firmware, or hardware, including the structures disclosed in this specification and their structural equivalents, or in combinations of one or more of them. Embodiments of the subject matter described in this specification can be implemented as one or more computer programs, i.e., one or more modules of computer program instructions, encoded on a computer storage medium for execution by, or to control the operation of, data processing apparatus. Alternatively or additionally, the program instructions may be encoded on a manually-generated propagated signal (e.g., a machine-generated electrical, optical, or electromagnetic signal that is generated to encode information for transmission to suitable receiver apparatus for execution by data processing apparatus). The computer storage medium may be or be included in a computer readable storage device, a computer readable storage substrate, a random or serial access memory array, or a device, or a combination thereof. Furthermore, while the computer storage medium is not a propagated signal, the computer storage medium may be a source or destination of computer program instructions encoded in an artificially generated propagated signal. Computer storage media may also be or be included in one or more separate physical components or media (e.g., a plurality of CDs, discs, or other storage devices). Furthermore, the operations described in this specification may be implemented as operations performed by a data processing apparatus on data stored on one or more computer readable storage devices or received from other sources.

While this specification may contain many specific implementation details, these should not be construed as limitations on the scope of any claimed subject matter, but rather as descriptions of features specific to particular embodiments. Certain features that are described in this specification in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination. Furthermore, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a subcombination or variation of a subcombination.

Similarly, although operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In some cases, multitasking and parallel processing may be advantageous. Moreover, the separation of various system components in the embodiments described above should not be understood as requiring such separation in all embodiments, and it should be understood that the described program components and systems can generally be integrated together in a single software product or packaged into multiple software products.

Thus, particular embodiments of the subject matter have been described herein. Other embodiments are within the scope of the following claims. In some cases, the actions recited in the claims can be performed in a different order and still achieve desirable results. Furthermore, the processes depicted in the accompanying drawings do not necessarily require the particular order shown, or sequential order, to achieve desirable results. In some implementations, multitasking and parallel processing may be advantageous.

As will be recognized by those skilled in the art, the innovative concepts described herein can be modified and varied over a wide range of applications. Accordingly, the scope of the claimed subject matter should not be limited to any of the specific exemplary teachings discussed above, but is defined by the following claims.

Claims

1. A method of a UE performing communication, the method comprising:

receiving a light Reference Signal (RS) on a carrier frequency where no Synchronization Signal Block (SSB) is detected;

in response to receiving the light RS, obtaining light RS measurements and transmitting light RS measurement reports based on the light RS measurements; and

based on the light RS measurement report, receiving at least one SSB on the carrier frequency is started.

2. The method of claim 1, further comprising:

Receiving Downlink Control Information (DCI) from a primary cell (PCell), the DCI indicating that the UE is to activate a Discontinuous Transmission (DTX) "on" mode to cause the UE to receive the at least one SSB on the carrier frequency; and

in response to receiving the DCI, a DTX "on" mode is activated.

3. The method of claim 2, further comprising:

receiving DCI from the PCell indicating that the UE is to activate a DTX "off" mode to stop the UE from receiving the at least one SSB on the carrier frequency; and

in response to receiving the DCI, a DTX "off" mode is activated.

4. The method of claim 1, further comprising:

a Radio Resource Control (RRC) signal identifying the configuration of the light RS is received,

wherein the RRC signal includes at least one of: the transmission period of the light RS, the frequency resource of the light RS, the time interval of the light RS, an index identifying the light RS, and a corresponding Synchronization Signal Block (SSB) quasi co-location (QCL) of the light RS.

5. The method of claim 1, wherein the light RSs comprise a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS) and do not comprise a Physical Broadcast Channel (PBCH).

6. A User Equipment (UE) configured to perform communication, the UE comprising:

a processor; and

a memory storing program instructions that, when executed by the processor, configure the UE to:

a light Reference Signal (RS) is received on a carrier frequency where no Synchronization Signal Block (SSB) is detected,

in response to receiving the light RS, obtaining light RS measurements and transmitting light RS measurement reports based on the light RS measurements, and

7. The UE of claim 6, wherein the instructions, when executed by the processor, further configure the UE to:

receiving Downlink Control Information (DCI) from a primary cell (PCell), the DCI indicating that the UE is to activate a Discontinuous Transmission (DTX) "on" mode to cause the UE to receive the at least one SSB on the carrier frequency, and

in response to receiving the DCI, a DTX "on" mode is activated.

8. The UE of claim 7, wherein the instructions, when executed by the processor, further configure the UE to:

receiving DCI from the PCell indicating that the UE is to activate a DTX "off" mode to stop the UE from receiving the at least one SSB on the carrier frequency, and

In response to receiving the DCI, a DTX "off" mode is activated.

9. The UE of claim 6, wherein the instructions, when executed by the processor, further configure the UE to:

10. The UE of claim 6, wherein the light RSs comprise a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS) and do not comprise a Physical Broadcast Channel (PBCH).

11. A method performed by a UE for activating a secondary cell (SCell), the method comprising:

receiving a Reference Signal (RS) for initiating a wake-up signal (WUS) transmission on a carrier frequency where no Synchronization Signal Block (SSB) is detected;

in response to receiving the RS, sending WUS to the SCell; and

based on WUS measurements obtained in response to the transmission of the WUS, receiving at least one SSB on the carrier frequency is started.

12. The method of claim 11, further comprising:

in response to receiving the DCI, a DTX "on" mode is activated.

13. The method of claim 11, wherein the RS is a light RS and includes a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS) and does not include a Physical Broadcast Channel (PBCH).

14. The method of claim 11, wherein the WUS is a preamble or a dedicated Sounding Reference Signal (SRS) combined with a dedicated Random Access Channel (RACH) occasion.

15. The method of claim 11, wherein the signal for switching from an inactive state to an active state is at least partially Downlink Control Information (DCI), and

wherein the DCI indicates an active or inactive state of a secondary cell (SCell).

16. A User Equipment (UE) configured to activate a secondary cell (SCell), the UE comprising:

a processor; and

a Reference Signal (RS) for initiating a wake-up signal (WUS) transmission is received on a carrier frequency where no Synchronization Signal Block (SSB) is detected,

Transmitting WUS to SCell in response to receiving RS, and

17. The UE of claim 16, wherein the instructions, when executed by the processor, further configure the UE to:

in response to receiving the DCI, a DTX "on" mode is activated.

18. The UE of claim 16, wherein the RS is a light RS and includes a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS) and does not include a Physical Broadcast Channel (PBCH).

19. The UE of claim 16, wherein the WUS is a preamble or a dedicated Sounding Reference Signal (SRS) combined with a dedicated Random Access Channel (RACH) occasion.

20. The UE of claim 16, wherein the signal for switching from an inactive state to an active state is at least partially Downlink Control Information (DCI), and