The present disclosure is generally related to mobile communications and, more particularly, to wake-up signal (WUS) transmission based on timing information with respect to user equipment (UE) and network apparatus in mobile communications.
Unless otherwise indicated herein, approaches described in this section are not prior art to the claims listed below and are not admitted as prior art by inclusion in this section.
The fifth-generation (5G) network, despite its enhanced energy efficiency in bits per Joule (e.g., 417% more efficiency than a 4G network) due to its larger bandwidth and better spatial multiplexing capabilities, may consume over 140% more energy than a 4G network.
For energy saving, 5G network may activate a sleep mode for a base station (BS) with low traffic loads. The sleep mode may turn off a power amplifier and other power-wasting components to save energy. When the traffic loads increase, network may deactivate the sleep mode for the base stations to balance the workload of neighboring base stations.
In order to deactivate the sleep mode, a signal used to wake up a base station is defined as a base station-wake-up signal (BS-WUS). The base station may receive the signal from the core 5G network or user equipments (UEs). However, it is unclear how the BS-WUS mechanism works in convention technologies.
Accordingly, how to transmit WUS becomes an important issue for the newly developed wireless communication network. Therefore, there is a need to provide proper schemes for WUS transmission for UE.
The following summary is illustrative only and is not intended to be limiting in any way. That is, the following summary is provided to introduce concepts, highlights, benefits and advantages of the novel and non-obvious techniques described herein. Select implementations are further described below in the detailed description. Thus, the following summary is not intended to identify essential features of the claimed subject matter, nor is it intended for use in determining the scope of the claimed subject matter.
An objective of the present disclosure is to propose solutions or schemes that address the aforementioned issues pertaining to transmit the wake-up signal (WUS) based on timing information with respect to user equipment and network apparatus in mobile communications.
In one aspect, a method may involve an apparatus receiving a system information and a timing information for waking up a non-anchor cell from an anchor cell. The method may also involve the apparatus transmitting a wake-up-signal (WUS) based on the system information and the timing information to wake up the non-anchor cell. The anchor cell comprises a cell where the apparatus is capable of receiving the system information and the timing information and performing a timing and frequency synchronization. The non-anchor cell comprises a cell where the apparatus cannot receive the system information and the timing information.
In one aspect, an apparatus may involve a transceiver which, during operation, wirelessly communicates with an anchor cell and a non-anchor cell of a wireless network. The apparatus may also involve a processor communicatively coupled to the transceiver such that, during operation, the processor performs following operations: receiving, via the transceiver, a system information and a timing information for waking up a non-anchor cell from an anchor cell; and transmitting, via the transceiver, a wake-up-signal (WUS) based on the system information and the timing information to wake up the non-anchor cell. The anchor cell comprises a cell where the apparatus is capable of receiving the system information and the timing information and performing a timing and frequency synchronization. The non-anchor cell comprises a cell where the apparatus cannot receive the system information and the timing information.
In one aspect, a method may involve an apparatus receiving a wake-up-signal (WUS) from a user equipment (UE). The method may also involve the apparatus waking up a second transceiver of the apparatus based on the WUS from the UE. The method may further involve the apparatus transiting from no or reduced transmission or reception activity to activate transmission or reception activity for a channel or a signal.
It is noteworthy that, although description provided herein may be in the context of certain radio access technologies, networks and network topologies such as Long-Term Evolution (LTE), LTE-Advanced, LTE-Advanced Pro, 5th Generation (5G), New Radio (NR), Internet-of-Things (IoT) and Narrow Band Internet of Things (NB-IoT), Industrial Internet of Things (IIOT), and 6th Generation (6G), the proposed concepts, schemes and any variation(s)/derivative(s) thereof may be implemented in, for and by other types of radio access technologies, networks and network topologies. Thus, the scope of the present disclosure is not limited to the examples described herein.
The accompanying drawings are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of the present disclosure. The drawings illustrate implementations of the disclosure and, together with the description, serve to explain the principles of the disclosure. It is appreciable that the drawings are not necessarily in scale as some components may be shown to be out of proportion than the size in actual implementation in order to clearly illustrate the concept of the present disclosure.
Detailed embodiments and implementations of the claimed subject matters are disclosed herein. However, it shall be understood that the disclosed embodiments and implementations are merely illustrative of the claimed subject matters which may be embodied in various forms. The present disclosure may, however, be embodied in many different forms and should not be construed as limited to the exemplary embodiments and implementations set forth herein. Rather, these exemplary embodiments and implementations are provided so that description of the present disclosure is thorough and complete and will fully convey the scope of the present disclosure to those skilled in the art. In the description below, details of well-known features and techniques may be omitted to avoid unnecessarily obscuring the presented embodiments and implementations.
Implementations in accordance with the present disclosure relate to various techniques, methods, schemes and/or solutions pertaining to using on-demand reference signal for network energy saving with respect to user equipment and network apparatus in mobile communications. According to the present disclosure, a number of possible solutions may be implemented separately or jointly. That is, although these possible solutions may be described below separately, two or more of these possible solutions may be implemented in one combination or another.
The present disclosure proposes several schemes pertaining to WUS transmission based on timing information with respect to UE and network apparatus in mobile communications.
In accordance with implementations of the present disclosure, the “sleeping cell” or the “cell in sleeping mode” may be defined as the cell has no transmission activity or reception activity, or the cell has reduced transmission activity or reception activity. The sleeping cell may be waked up by the WUS signal. The WUS signal is used to request transmission from no or reduced transmission or reception activity to activate transmission or reception activity of a channel or a signal before the sleeping cell has been waked up. In addition, the WUS signal is used to trigger a synchronization signal (SS)/physical broadcast channel (PBCH) block (SSB) or system information block (SIB) transmission after the sleeping cell has been waked up.
Furthermore, in accordance with implementations of the present disclosure, the “non-anchor cell” may be defined as a sleeping cell without SIB or without SIB and SSB, i.e., the UE may not receive the SIB or not receive the SIB and SSB in the non-anchor cell. The “anchor cell” may be defined as a cell where the UE is capable of receiving SSB, system information and paging. In addition, in the present disclosure, the non-anchor cell may be associated with the anchor cell.
A network node may enter energy savings autonomously by monitoring the current traffic load, but the network node may be unclear to know whether it can leave the sleep mode autonomously without base station (BS)-WUS. Therefore, the present disclosure proposes some solutions to resolve the issues.
When the UE cannot find a suitable cell, the UE may need to wake up any sleeping cell nearby. The legacy random access (RA) procedure may be reused to minimize spec impact, e.g., the legacy cell may not know the signaling based on new spec from the sleeping cell.
A new cellBarred bit may be provided in MIB or SIB1 and denoted by allowed-wake-up. The cellBarred bit may be an always present bit as ENUMERATED {allowed, notAllowed}, or optionally present bit as ENUMERATED {allowed}. When the UE receives the allowed-wake-up field set to “allowed” in a cell, the UE may ignore cellBarred bit, and perform cell selection and random access on the cell, i.e., the new UE may allow to camp on the sleeping cell.
The sleeping cell may broadcast SSB and SIB1 for UE to transmit a BS-WUS using physical random access channel (PRACH) preamble. However, the broadcast may be an energy waste since there is not any data transmission in the broadcast. Therefore, the present disclosure proposes some solutions to resolve the issues.
DEN derivation from GNSS may include Tcurrent, Tref, OffsetDFN, and u. Tcurrent is the current UTC obtained from GNSS. The value of Tcurrent may be expressed in milliseconds. Tref is the reference UTC 00:00:00 on Gregorian calendar date 1 Jan. 1900 (midnight between Thursday, Dec. 31, 1899, and Friday, Jan. 1, 1900). The value of Tref may be expressed in milliseconds. OffsetDFN is the value of sl-OffsetDFN if configured. Otherwise, OffsetDFN is zero. The value of OffsetDFN may be expressed in milliseconds. μ=0/1/2/3 may correspond to the 15/30/60/120 kHz of subcarrier spacing (SCS).
In another example, the GNSS satellite may be replaced by a satellite that provides NR service or an NR cell. In this case, the NR satellite or the NR cell may provide the pre-defined random access (RA) resources and the synchronization timing.
The UE may select an SSB with synchronization signal (SS)-Reference Signal Received Power (RSRP) above rsrp-ThresholdSSB (or msgA-RSRP-ThresholdSSB) and sets the PREAMBLE_INDEX to a ra-PreambleIndex. However, if there is no SS-RSRP, the UE may not select the SSB, the preamble, and the random access (RA) types. In addition, since there is no SIB1, there is no configuration for the RA procedure. Therefore, the present disclosure proposes some solutions to resolve the issues.
The pre-defined configuration may be provided from any cell, including the sleeping cell if connected before. The pre-defined configuration may be provided via RRC signaling, e.g., RRCRelease message. The pre-defined configuration may be stored by the UE. The UE may use the stored information to transmit the pre-defined PRACH preamble to the sleeping cell when there is no cell to camp on, e.g., out of coverage.
The pre-defined configuration may be a subset of rach-ConfigDedicated. The information element (IE) rach-ConfigDedicated is used as the random access configuration for the reconfiguration with synchronization (e.g., handover). The UE may perform the RA according to the parameters in the firstActiveUplinkBWP of UplinkConfig.
For example, a compact configuration may be provided from any cell, including the sleeping cell. The compact configuration may have fields with 111 bits. These bits may be saved if a fixed configuration is specified. The fields may comprise following information elements (IEs).
The IE rach-ConfigGeneric is to specify the random-access parameters both for regular random access as well as for beam failure recovery.
The IE prach-ConfigurationIndex is the PRACH configuration index.
The IE msg1-FDM is for the number of PRACH transmission occasions frequency-division multiplexed (FDMed) in a one-time instance.
The IE msg1-Frequency Start is for offset of the lowest PRACH transmission occasion in the frequency domain concerning physical resource block (PRB) 0. The value is configured so that the corresponding RACH resource is entirely within the bandwidth of the UL Bandwidth Part (BWP).
The IE zeroCorrelationZoneConfig is the N-CS configuration.
The IE preambleReceivedTargetPower is the target power level at the network receiver side.
The IE preambleTransMax is the max number of RA preamble transmissions performed before declaring a failure.
The IE powerRampingStep is the power ramping steps for PRACH.
The IE ra-ResponseWindow is the Msg2 (RAR) window length in a number of slots. The network configures a value lower than or equal to 10 ms when Msg2 is transmitted in licensed spectrum and a value lower than or equal to 40 ms when Msg2 is transmitted with shared spectrum channel access.
The IE ssb-perRACH-Occasion is the number of SSBs per RACH occasion.
The IE ra-PreambleIndex is the preamble index that the UE shall use when performing CF-RA upon selecting the candidate beams identified by this SSB.
The IE ra-ssb-OccasionMaskIndex is the explicitly signaled PRACH Mask Index for RA Resource selection. The mask is valid for all SSB resources signaled in ssb-ResourceList.
The IE SubcarrierSpacing is the subcarrier spacing of this carrier. The IE SubcarrierSpacing is used to convert the offsetToCarrier into an actual frequency.
The IE locationAndBandwidth refers to this bandwidth part's frequency domain location and bandwidth. The first PRB is a PRB determined by subcarrierSpacing of this BWP and offsetToCarrier.
The IE offsetToCarrier is offset in the frequency domain between Point A (lowest subcarrier of common RB 0) and the lowest usable subcarrier on this carrier in the number of PRBs (using the subcarrierSpacing defined for this carrier).
The IE absoluteFrequencyPointA represents the frequency-location of point A expressed as in absolute radio-frequency channel number (ARFCN). Point A serves as a common reference point for resource block grids.
The IE ARFCN-ValueNR indicates the ARFCN applicable for a downlink, uplink, or bi-directional (TDD) NR global frequency raster.
Reusing PRACH preambles as BS-WUS may lead to interference for other cells. The UE in a normal cell may accidentally wake up a sleeping cell due to using a pre-defined PRACH preamble.
In addition, using a GNSS receiver in RRC_IDLE may significantly waste UE's power. Therefore, the present disclosure proposes some solutions to resolve the issues.
However, it is unclear how to introduce WUR in NR. Therefore, the present disclosure proposes some solutions to resolve the issues.
The wake-up preamble 910 may use on-off keying (OOK) modulation and ZC sequence. OOK uses ‘1’s or ‘0’s, where an amplitude carrier is sent for ‘1’ and nothing is sent for ‘0’, i.e., the transmitter can be turned off. The receiver senses the rising edge of the digital signal from low to high via the RF front-end.
The address ID 920 and sender ID 930 may include cell ID and UE ID. The address ID 920 refers to a destination for the WUS, and the sender ID 930 refers to where the WUS is from. CRC 940 is used for error correction. Cell-Radio Network Temporary Identifier (C-RNTI) may scramble CRC to provide UE ID.
The UE may keep sending BS-WUS to fit the quality of service (QOS). However, it may lead to power consumption of the UE. Therefore, a prohibit timer may start when UE transmits a BS-WUS. When the prohibit timer runs, the UE may not be permitted to transmit another BS-WUS. The prohibit timer value may be provided in SIB.
The sleeping cell may bar the cell from protecting the legacy UE. However, it may prevent any chance to receive a BS-WUS. Therefore, the UE may receive a new field in MIB or SIB1 to indicate whether the cell can be woken up via BS-WUS. If the indication is present, the UE may transmit the BS-WUS to wake up the sleeping cell via a PRACH preamble or WUS, regardless of the cellBarred field. The configuration for the BS-WUS may be via SIB1 or other SIBs.
Communication apparatus 1110 may be a part of an electronic apparatus, which may be a UE such as a portable or mobile apparatus, a wearable apparatus, a wireless communication apparatus or a computing apparatus. For instance, communication apparatus 1110 may be implemented in a smartphone, a smartwatch, a personal digital assistant, a digital camera, or a computing equipment such as a tablet computer, a laptop computer or a notebook computer. Communication apparatus 1110 may also be a part of a machine type apparatus, which may be an IoT, NB-IoT, or IIOT apparatus such as an immobile or a stationary apparatus, a home apparatus, a wire communication apparatus or a computing apparatus. For instance, communication apparatus 1110 may be implemented in a smart thermostat, a smart fridge, a smart door lock, a wireless speaker or a home control center. Alternatively, communication apparatus 1110 may be implemented in the form of one or more integrated-circuit (IC) chips such as, for example and without limitation, one or more single-core processors, one or more multi-core processors, one or more reduced-instruction set computing (RISC) processors, or one or more complex-instruction-set-computing (CISC) processors. Communication apparatus 1110 may include at least some of those components shown in
Network apparatus 1120 may be a part of a network apparatus, which may be a network node such as a satellite, a base station, a small cell, a router or a gateway. For instance, network apparatus 1120 may be implemented in an eNodeB in an LTE network, in a gNB in a 5G/NR, IoT, NB-IoT or IIOT network or in a satellite or base station in a 6G network. Alternatively, network apparatus 1120 may be implemented in the form of one or more IC chips such as, for example and without limitation, one or more single-core processors, one or more multi-core processors, or one or more RISC or CISC processors. Network apparatus 1120 may include at least some of those components shown in
In one aspect, each of processor 1112 and processor 1122 may be implemented in the form of one or more single-core processors, one or more multi-core processors, or one or more CISC processors. That is, even though a singular term “a processor” is used herein to refer to processor 1112 and processor 1122, each of processor 1112 and processor 1122 may include multiple processors in some implementations and a single processor in other implementations in accordance with the present disclosure. In another aspect, each of processor 1112 and processor 1122 may be implemented in the form of hardware (and, optionally, firmware) with electronic components including, for example and without limitation, one or more transistors, one or more diodes, one or more capacitors, one or more resistors, one or more inductors, one or more memristors and/or one or more varactors that are configured and arranged to achieve specific purposes in accordance with the present disclosure. In other words, in at least some implementations, each of processor 1112 and processor 1122 is a special-purpose machine specifically designed, arranged and configured to perform specific tasks including autonomous reliability enhancements in a device (e.g., as represented by communication apparatus 1110) and a network (e.g., as represented by network apparatus 1120) in accordance with various implementations of the present disclosure.
In some implementations, communication apparatus 1110 may also include a transceiver 1116 coupled to processor 1112 and capable of wirelessly transmitting and receiving data. In some implementations, transceiver 1116 may comprise a WUR transceiver and a normal transceiver as transceiver 700. In some implementations, communication apparatus 1110 may further include a memory 1114 coupled to processor 1112 and capable of being accessed by processor 1112 and storing data therein. In some implementations, network apparatus 1120 may also include a transceiver 1126 coupled to processor 1122 and capable of wirelessly transmitting and receiving data. In some implementations, transceiver 1126 may comprise a WUR transceiver and a normal transceiver as transceiver 700. In some implementations, network apparatus 1120 may further include a memory 1124 coupled to processor 1122 and capable of being accessed by processor 1122 and storing data therein. Accordingly, communication apparatus 1110 and network apparatus 1120 may wirelessly communicate with each other via transceiver 1116 and transceiver 1126, respectively. To aid better understanding, the following description of the operations, functionalities and capabilities of each of communication apparatus 1110 and network apparatus 1120 is provided in the context of a mobile communication environment in which communication apparatus 1110 is implemented in or as a communication apparatus or a UE and network apparatus 1120 is implemented in or as a network node of a communication network.
In some implementations, processor 1112 may receive, via transceiver 1116, a system information and a timing information for waking up a non-anchor cell from an anchor cell. Processor 1112 may transmit, via transceiver 1116, a WUS based on the system information and the timing information to wake up the non-anchor cell. The anchor cell comprises a cell where communication apparatus 1110 is capable of receiving the system information and the timing information and performing a timing and frequency synchronization. The non-anchor cell comprises a cell where communication apparatus 1110 cannot receive the system information and the timing information.
In some implementations, processor 1112 may receive, via transceiver 1116, the timing information from at least one Global Navigation Satellite System (GNSS) satellite.
In some implementations, processor 1112 may perform a cell selection, a cell re-selection or a random access procedure with the non-anchor cell based on the system information and the timing information.
In some implementations, the system information comprises a configuration for at least one of carrier information, physical random access channel (PRACH) transmission, a preamble index, a preamble sub-carrier spacing (SCS) and a PRACH resource.
In some implementations, the WUS comprises a base station (BS)-WUS sequence, and wherein the WUS is used to request a transition from no or reduced transmission or reception activity to activate transmission or reception activity of a channel or a signal, or is used to trigger a synchronization signal block (SSB) or system information block (SIB) transmission.
In some implementations, processor 1112 may transmit the WUS through a wake-up transceiver of the transceiver 1116.
In some implementations, the WUS comprises at least one of a wake-up preamble, an address identification (ID), a sender ID and a sub-carrier spacing (SCS).
In some implementations, processor 1112 may start a prohibit timer in an event that the WUS is transmitted to the non-anchor cell. Processor 1112 may stop transmit another WUS when the prohibit timer is running.
In some implementations, processor 1112 may receive, via transceiver 1116, a master information block (MIB) or a system information block 1 (SIB1) to determine whether wake up the non-anchor cell.
In some implementations, processor 1122 may receive, via a first transceiver of transceiver 1126 a WUS from communication apparatus 1110. Processor 1122 may wake, via the first transceiver of transceiver 1126, a second transceiver of transceiver of transceiver 1126 up based on the WUS from the UE communication apparatus 1110. Processor 1122 may transit from no or reduced transmission or reception activity to activate transmission or reception activity for a channel or a signal.
In some implementations, the second transceiver of transceiver 1126 is in a power saving mode in an event that processor 1122 is in no or reduced transmission or reception activity
At 1210, process 1200 may involve processor 1112 of communication apparatus 1110 receiving a system information and a timing information for waking up a non-anchor cell from an anchor cell. The anchor cell comprises a cell where the apparatus is capable of receiving the system information and the timing information and performing a timing and frequency synchronization. The non-anchor cell comprises a cell where the apparatus cannot receive the system information and the timing information. Process 1200 may proceed from 1210 to 1220.
At 1220, process 1200 may involve processor 1112 transmitting a WUS based on the system information and the timing information to wake up the non-anchor cell.
At 1310, process 1300 may involve a first transceiver of transceiver 1126 of network apparatus 1120 receiving a WUS from a UE. Process 1300 may proceed from 1310 to 1320.
At 1320, process 1300 may involve the first transceiver waking up a second transceiver of transceiver 1126 based on the WUS from the UE. Process 1300 may proceed from 1320 to 1330.
At 1330, process 1300 may involve processor 1122 of network apparatus 1120 transiting from no or reduced transmission or reception activity to activate transmission or reception activity for a channel or a signal.
The herein-described subject matter sometimes illustrates different components contained within, or connected with, different other components. It is to be understood that such depicted architectures are merely examples, and that in fact many other architectures can be implemented which achieve the same functionality. In a conceptual sense, any arrangement of components to achieve the same functionality is effectively “associated” such that the desired functionality is achieved. Hence, any two components herein combined to achieve a particular functionality can be seen as “associated with” each other such that the desired functionality is achieved, irrespective of architectures or intermedial components. Likewise, any two components so associated can also be viewed as being “operably connected”, or “operably coupled”, to each other to achieve the desired functionality, and any two components capable of being so associated can also be viewed as being “operably couplable”, to each other to achieve the desired functionality. Specific examples of operably couplable include but are not limited to physically mateable and/or physically interacting components and/or wirelessly interactable and/or wirelessly interacting components and/or logically interacting and/or logically interactable components.
Further, with respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.
Moreover, it will be understood by those skilled in the art that, in general, terms used herein, and especially in the appended claims, e.g., bodies of the appended claims, are generally intended as “open” terms, e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc. It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to implementations containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an,” e.g., “a” and/or “an” should be interpreted to mean “at least one” or “one or more;” the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should be interpreted to mean at least the recited number, e.g., the bare recitation of “two recitations,” without other modifiers, means at least two recitations, or two or more recitations. Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention, e.g., “a system having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc. In those instances where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention, e.g., “a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc. It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B.”
From the foregoing, it will be appreciated that various implementations of the present disclosure have been described herein for purposes of illustration, and that various modifications may be made without departing from the scope and spirit of the present disclosure. Accordingly, the various implementations disclosed herein are not intended to be limiting, with the true scope and spirit being indicated by the following claims.
The present disclosure claims the priority benefit of U.S. Provisional Patent Application No. 63/321,859, filed on 21 Mar. 2022. The content of aforementioned application is herein incorporated by reference in its entirety.
Filing Document | Filing Date | Country | Kind |
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PCT/CN2023/082603 | 3/20/2023 | WO |
Number | Date | Country | |
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63321859 | Mar 2022 | US |