Patent Application
20240314692
The following disclosure relates to communication apparatuses and communication methods for operating in a power saving state, and more particularly for a sidelink user equipment (UE).
Vehicle-to-everything (V2X) communication allows vehicles to interact with public roads and other road users, and is thus considered a critical factor in making autonomous vehicles a reality.
To accelerate this process, 5G new radio access technology (NR) based V2X communications (interchangeably referred to as NR V2X communications) is being discussed by the 3rd Generation Partnership Project (3GPP) to identify technical solutions for advanced V2X services, through which vehicles (i.e. interchangeably referred to as communication apparatuses or user equipments (UEs) that support V2X applications) can exchange their own status information through sidelink (SL) with other nearby vehicles, infrastructure nodes and/or pedestrians. The status information includes information on position, speed, heading, etc.
According to identification in Release 17 (Rel-17) V2X Work Item Description (WID) (RP-202846), power saving enables UEs with battery constraint to perform sidelink operations in a power efficient manner. Rel-16 NR sidelink is designed based on the assumption of “always-on” when UE operates sidelink, e.g., only focusing on UEs installed in vehicles with sufficient battery capacity. Solution for power saving in Rel-17 are required for vulnerable road users (VRUs) in V2X use cases and for UEs in public safety and commercial use cases where power consumption in the UEs needs to be minimized.
Also, in RAN1 #103-e meeting, two UE reception type (i.e. with or without reception capability) has been concluded for evaluation and power saving features in Rel-17.
In particular, it is not clear how a SL UE should become power saving, and how a SL UE balances its power saving with performance requirements.
Hence, there is a need to address one or more of the above challenges and develop new communication apparatuses and communication methods for operating in a power saving state. Furthermore, other desirable features and characteristics will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and this background of the disclosure.
One non-limiting and exemplary embodiment facilitates providing communication apparatuses and methods for utilisation of SL-RSRP in V2X resource sensing & selection.
In a first aspect, the present disclosure provides a communication apparatus comprising: circuitry, which in operation, determines one of a plurality of power saving states to operate in; and a transceiver, which in operation, transmit and/or receive at least one type of sidelink signals in response to determining the one of the plurality of power saving states.
In a second aspect, the present disclosure provides a communication method comprising: determining one of a plurality of power saving states to operate in; and transmitting and/or receiving at least one type of sidelink signals in response to determining the one of the plurality of power saving states.
It should be noted that general or specific embodiments may be implemented as a system, a method, an integrated circuit, a computer program, a storage medium, or any selective combination thereof.
Additional benefits and advantages of the disclosed embodiments will become apparent from the specification and drawings. The benefits and/or advantages may be individually obtained by the various embodiments and features of the specification and drawings, which need not all be provided in order to obtain one or more of such benefits and/or advantages.
Embodiments of the disclosure will be better understood and readily apparent to one of ordinary skilled in the art from the following written description, by way of example only, and in conjunction with the drawings, in which:
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been depicted to scale. For example, the dimensions of some of the elements in the illustrations, block diagrams or flowcharts may be exaggerated in respect to other elements to help to improve understanding of the present embodiments.
Some embodiments of the present disclosure will be described, by way of example only, with reference to the drawings. Like reference numerals and characters in the drawings refer to like elements or equivalents.
3GPP has been working at the next release for the 5th generation cellular technology, simply called 5G, including the development of a new radio access technology (NR) operating in frequencies ranging up to 100 GHz. The first version of the 5G standard was completed at the end of 2017, which allows proceeding to 5G NR standard-compliant trials and commercial deployments of smartphones. The second version of the 5G standard was completed in June 2020, which further expand the reach of 5G to new services, spectrum and deployment such as unlicensed spectrum (NR-U), non-public network (NPN), time sensitive networking (TSN) and cellular-V2X.
Among other things, the overall system architecture assumes an NG-RAN (Next Generation-Radio Access Network) that comprises gNBs, providing the NG-radio access user plane (SDAP/PDCP/RLC/MAC/PHY) and control plane (RRC) protocol terminations towards the UE. The gNBs are interconnected with each other by means of the Xn interface. The gNBs are also connected by means of the Next Generation (NG) interface to the NGC (Next Generation Core), more specifically to the AMF (Access and Mobility Management Function) (e.g. a particular core entity performing the AMF) by means of the NG-C interface and to the UPF (User Plane Function) (e.g. a particular core entity performing the UPF) by means of the NG-U interface. The NG-RAN architecture is illustrated in
The user plane protocol stack for NR (see e.g. 3GPP TS 38.300, section 4.4.1) comprises the PDCP (Packet Data Convergence Protocol, see section 6.4 of TS 38.300), RLC (Radio Link Control, see section 6.3 of TS 38.300) and MAC (Medium Access Control, see section 6.2 of TS 38.300) sublayers, which are terminated in the gNB on the network side. Additionally, a new access stratum (AS) sublayer (SDAP, Service Data Adaptation Protocol) is introduced above PDCP (see e.g. sub-clause 6.5 of 3GPP TS 38.300). A control plane protocol stack is also defined for NR (see for instance TS 38.300, section 4.4.2). An overview of the Layer 2 functions is given in sub-clause 6 of TS 38.300. The functions of the PDCP, RLC and MAC sublayers are listed respectively in sections 6.4, 6.3, and 6.2 of TS 38.300. The functions of the RRC layer are listed in sub-clause 7 of TS 38.300.
For instance, the Medium-Access-Control layer handles logical-channel multiplexing, and scheduling and scheduling-related functions, including handling of different numerologies.
The physical layer (PHY) is for example responsible for coding, PHY hybrid automatic repeat request (HARQ) processing, modulation, multi-antenna processing, and mapping of the signal to the appropriate physical time-frequency resources. It also handles mapping of transport channels to physical channels. The physical layer provides services to the MAC layer in the form of transport channels. A physical channel corresponds to the set of time-frequency resources used for transmission of a particular transport channel, and each transport channel is mapped to a corresponding physical channel. For instance, the physical channels are PRACH (Physical Random Access Channel), PUSCH (Physical Uplink Shared Channel) and PUCCH (Physical Uplink Control Channel) for uplink, PDSCH (Physical Downlink Shared Channel), PDCCH (Physical Downlink Control Channel) and PBCH (Physical Broadcast Channel) for downlink, and PSSCH (Physical Sidelink Shared Channel), PSCCH (Physical Sidelink Control Channel) and Physical Sidelink Feedback Channel (PSFCH) for sidelink (SL).
SL supports UE-to-UE direct communication using the SL resource allocation modes, physical layer signals/channels, and physical layer procedures. Two SL resource allocation mode are supported: (a) mode 1, where the SL resource allocation is provided by the network; and (b) mode 2, where UE decides SL transmission resource in the resource pool(s).
PSCCH indicates resource and other transmission parameters used by a UE for PSSCH. PSCCH transmission is associated with a demodulation reference signal (DM-RS). PSSCH transmits the transport blocks (TBs) of data themselves, and control information for HARQ procedure and channel state information (CSI) feedback triggers, etc. At least 6 Orthogonal Frequency Division Multiplex (OFDM) symbols within a slot are used for PSSCH transmission. PSSCH transmission is associated with a DM-RS and may be associated with a phase-tracking reference signal (PT-RS).
PSFCH carries HARQ feedback over the SL from a UE which is an intended recipient of a PSSCH transmission to the UE which performed the transmission. PSFCH sequence is transmitted in one PRB repeated over two OFDM symbols near the end of the SL resource in a slot.
The SL synchronization signal consists of SL primary and SL secondary synchronization signals (S-PSS, S-SSS), each occupying 2 symbols and 127 subcarriers. Physical Sidelink Broadcast Channel (PSBCH) occupies 9 and 5 symbols for normal and extended cyclic prefix cases respectively, including the associated demodulation reference signal (DM-RS).
Regarding physical layer procedure for HARQ feedback for sidelink, SL HARQ feedback uses PSFCH and can be operated in one of two options. In one option, which can be configured for unicast and groupcast, PSFCH transmits either ACK or NACK using a resource dedicated to a single PSFCH transmitting UE. In another option, which can be configured for groupcast, PSFCH transmits NACK, or no PSFCH signal is transmitted, on a resource that can be shared by multiple PSFCH transmitting UEs.
In SL resource allocation mode 1, a UE which received PSFCH can report SL HARQ feedback to gNB via PUCCH or PUSCH.
Regarding physical layer procedure for power control for sidelink, for in-coverage operation, the power spectral density of the SL transmissions can be adjusted based on the pathloss from the gNB; whereas for unicast, the power spectral density of some SL transmissions can be adjusted based on the pathloss between the two communicating UEs.
Regarding physical layer procedure for CSI report, for unicast, channel state information reference signal (CSI-RS) is supported for CSI measurement and reporting in sidelink. A CSI report is carried in a SL MAC CE.
For measurement on the sidelink, the following UE measurement quantities are supported:
Use cases/deployment scenarios for NR could include enhanced mobile broadband (eMBB), ultra-reliable low-latency communications (URLLC), massive machine type communication (mMTC), which have diverse requirements in terms of data rates, latency, and coverage. For example, eMBB is expected to support peak data rates (20 Gbps for downlink and 10 Gbps for uplink) and user-experienced data rates in the order of three times what is offered by IMT-Advanced. On the other hand, in case of URLLC, the tighter requirements are put on ultra-low latency (0.5 ms for UL and DL each for user plane latency) and high reliability (1-10−5 within 1 ms). Finally, mMTC may preferably require high connection density (1,000,000 devices/km2 in an urban environment), large coverage in harsh environments, and extremely long-life battery for low cost devices (15 years).
Therefore, the OFDM numerology (e.g. subcarrier spacing, OFDM symbol duration, cyclic prefix (CP) duration, number of symbols per scheduling interval) that is suitable for one use case might not work well for another. For example, low-latency services may preferably require a shorter symbol duration (and thus larger subcarrier spacing) and/or fewer symbols per scheduling interval (aka, TTI) than an mMTC service. Furthermore, deployment scenarios with large channel delay spreads may preferably require a longer CP duration than scenarios with short delay spreads. The subcarrier spacing should be optimized accordingly to retain the similar CP overhead. NR may support more than one value of subcarrier spacing. Correspondingly, subcarrier spacing of 15 kHz, 30 kHz, 60 kHz . . . are being considered at the moment. The symbol duration Tu and the subcarrier spacing Δf are directly related through the formula Δf=1/Tu. In a similar manner as in LTE systems, the term “resource element” can be used to denote a minimum resource unit being composed of one subcarrier for the length of one OFDM/SC-FDMA symbol.
In the new radio system 5G-NR for each numerology and carrier a resource grid of subcarriers and OFDM symbols is defined respectively for uplink and downlink. Each element in the resource grid is called a resource element and is identified based on the frequency index in the frequency domain and the symbol position in the time domain (see 3GPP TS 38.211 v16.3.0).
In particular, the gNB and ng-eNB host the following main functions:
The Access and Mobility Management Function (AMF) hosts the following main functions:
Furthermore, the User Plane Function, UPF, hosts the following main functions:
Finally, the Session Management function, SMF, hosts the following main functions:
RRC is a higher layer signaling (protocol) used for UE and gNB configuration. In particular, this transition involves that the AMF prepares the UE context data (including e.g. PDU session context, the Security Key, UE Radio Capability and UE Security Capabilities, etc.) and sends it to the gNB with the INITIAL CONTEXT SETUP REQUEST. Then, the gNB activates the AS security with the UE, which is performed by the gNB transmitting to the UE a SecurityModeCommand message and by the UE responding to the gNB with the SecurityModeComplete message. Afterwards, the gNB performs the reconfiguration to setup the Signaling Radio Bearer 2, SRB2, and Data Radio Bearer(s), DRB(s) by means of transmitting to the UE the RRCReconfiguration message and, in response, receiving by the gNB the RRCReconfigurationComplete from the UE. For a signaling-only connection, the steps relating to the RRCReconfiguration are skipped since SRB2 and DRBs are not setup. Finally, the gNB informs the AMF that the setup procedure is completed with the INITIAL CONTEXT SETUP RESPONSE.
The URLLC use case has stringent requirements for capabilities such as throughput, latency and availability and has been envisioned as one of the enablers for future vertical applications such as wireless control of industrial manufacturing or production processes, remote medical surgery, distribution automation in a smart grid, transportation safety, etc. Ultra-reliability for URLLC is to be supported by identifying the techniques to meet the requirements set by TR 38.913. For NR URLLC in Release 15, key requirements include a target user plane latency of 0.5 ms for UL (uplink) and 0.5 ms for DL (downlink). The general URLLC requirement for one transmission of a packet is a BLER (block error rate) of 1E-5 for a packet size of 32 bytes with a user plane latency of 1 ms.
From the physical layer perspective, reliability can be improved in a number of possible ways. The current scope for improving the reliability involves defining separate CQI tables for URLLC, more compact DCI formats, repetition of PDCCH, etc. However, the scope may widen for achieving ultra-reliability as the NR becomes more stable and developed (for NR URLLC key requirements). Particular use cases of NR URLLC in Rel. 15 include Augmented Reality/Virtual Reality (AR/VR), e-health, e-safety, and mission-critical applications.
Moreover, technology enhancements targeted by NR URLLC aim at latency improvement and reliability improvement. Technology enhancements for latency improvement include configurable numerology, non slot-based scheduling with flexible mapping, grant free (configured grant) uplink, slot-level repetition for data channels, and downlink pre-emption. Pre-emption means that a transmission for which resources have already been allocated is stopped, and the already allocated resources are used for another transmission that has been requested later, but has lower latency/higher priority requirements. Accordingly, the already granted transmission is pre-empted by a later transmission. Pre-emption is applicable independent of the particular service type. For example, a transmission for a service-type A (URLLC) may be pre-empted by a transmission for a service type B (such as eMBB). Technology enhancements with respect to reliability improvement include dedicated CQI/MCS tables for the target BLER of 1E-5.
The use case of mMTC (massive machine type communication) is characterized by a very large number of connected devices typically transmitting a relatively low volume of non-delay sensitive data. Devices are required to be low cost and to have a very long battery life. From NR perspective, utilizing very narrow bandwidth parts is one possible solution to have power saving from UE perspective and enable long battery life.
As mentioned above, it is expected that the scope of reliability in NR becomes wider. One key requirement to all the cases, and especially necessary for URLLC and mMTC, is high reliability or ultra-reliability. Several mechanisms can be considered to improve the reliability from radio perspective and network perspective. In general, there are a few key potential areas that can help improve the reliability. Among these areas are compact control channel information, data/control channel repetition, and diversity with respect to frequency, time and/or the spatial domain. These areas are applicable to reliability in general, regardless of particular communication scenarios.
For NR URLLC, further use cases with tighter requirements have been identified such as factory automation, transport industry and electrical power distribution, including factory automation, transport industry, and electrical power distribution. The tighter requirements are higher reliability (up to 10−6 level), higher availability, packet sizes of up to 256 bytes, time synchronization down to the order of a few us where the value can be one or a few us depending on frequency range and short latency in the order of 0.5 to 1 ms in particular a target user plane latency of 0.5 ms, depending on the use cases.
Moreover, for NR URLLC, several technology enhancements from the physical layer perspective have been identified. Among these are PDCCH (Physical Downlink Control Channel) enhancements related to compact DCI, PDCCH repetition, increased PDCCH monitoring. Moreover, UCI (Uplink Control Information) enhancements are related to enhanced HARQ (Hybrid Automatic Repeat Request) and CSI feedback enhancements. Also PUSCH enhancements related to mini-slot level hopping and retransmission/repetition enhancements have been identified. The term “mini-slot” refers to a Transmission Time Interval (TTI) including a smaller number of symbols than a slot (a slot comprising fourteen symbols).
The 5G QoS (Quality of Service) model is based on QoS flows and supports both QoS flows that require guaranteed flow bit rate (GBR QoS flows) and QoS flows that do not require guaranteed flow bit rate (non-GBR QoS Flows). At NAS level, the QoS flow is thus the finest granularity of QoS differentiation in a PDU session. A QoS flow is identified within a PDU session by a QoS flow ID (QFI) carried in an encapsulation header over NG-U interface.
For each UE, 5GC establishes one or more PDU Sessions. For each UE, the NG-RAN establishes at least one Data Radio Bearers (DRB) together with the PDU Session, and additional DRB(s) for QoS flow(s) of that PDU session can be subsequently configured (it is up to NG-RAN when to do so), e.g. as shown above with reference to
According to European Telecommunication Standards Institute (ETSI) technical report (TR) 103 300, the abstracted flow from V2X use cases for vulnerable road users (VRUs) includes:
As mentioned earlier, for the safety concern of VRUs, the most fundamental step is the Detection of the VRU presence. It is not clear when a VRU-UE should transmit its SL broadcast signal and security message to indicate its presence. It is further noted that, in LTE and NR uplink and downlink (Uu), DRX is used for power saving purpose. A VRU-UE only needs to wake up DRX on-duration to monitor possible PDCCHs and perform potential transmission. On this basis, a UE with SL capability should utilize DRX features as much as possible to reduce wake-up times for power saving purposes.
In various embodiments below, the following type of road users are considered as vulnerable road users (VRU) according to ETSI TR 103 300 and also the classification in Annex 1 of Regulation (EU) 168/2013 [i.8]:
In various embodiments below, a communication apparatus may refer to a sidelink UE. The sidelink UE may transmit and/or receive sidelink signals such as Physical Sidelink Control Channels (PSCCHs), Physical Sidelink Shared Channels (PSSCHs), Sidelink Synchronization Blocks (S-SSBs), Physical Sidelink Feedback Channels (PSFCHs), first-stage and second-stage Sidelink Control Information (SCI), Downlink Control Indication signal, Radio Resource Control signal, Media Access Control (MAC) Control Element (CE), Radio Resource Control (RRC) signal, Physical Downlink Control Channels (PDCCHs), Sidelink Synchronization Signals (SLSSs), Physical Sidelink Broadcast Channel (PSBCHs), and Physical Sidelink Feedback Channels (PSFCHs).
According to the present disclosure, a communication apparatus may be configured to operate or determine to operate in a power saving state. The power saving state may be one of a plurality of power saving states operable by the communication apparatus. Each of the one of the plurality of power saving states corresponds to different features/capabilities featuring a different level of power saving during operation.
In various embodiments, where a communication apparatus may refer to a sidelink (SL) user equipment (UE), another communication apparatus may communicate with the sidelink UE through transmitting and/or receiving sidelink signals, the other communication apparatus being one of (i) a base station (gNodeB or gNB) or a cellular network, where the sidelink UE is within a network coverage of the base station or the cellular network, and (ii) another sidelink UE regardless of whether or not both the sidelink UE and the other sidelink UE are within a network coverage of a base station.
In various embodiments, a default power saving state or an initial power saving state may be one of the plurality of power saving states that is (pre-)configured to be operated by a communication apparatus. Such default/initial power saving state can be either the most power-saving state, the most power-consuming state, or a preferred/suitable power saving state determined by the communication apparatus or by another communication apparatus (e.g. gNB, another SL UE) based on the current operating conditions and parameters, or any other state. Such default power saving state can also be (pre-)configured or (pre-)defined by either specifications (e.g. 3GPP specification), government regulators or UE vendors.
In various embodiments, the term “state” in power saving state can be used interchangeably with “mode”, “scheme”, “type” and “level”.
In various embodiments, parameters relating to a communication apparatus may refer to relevant factors considered and used for determining a power saving state to operate such a transmission/reception priority of the communication apparatus, a velocity in which the communication apparatus is moving, a communication apparatus type, a vehicle type (e.g. train, bus, van, sedan, bicycle), a Global Navigation Satellite System (GNSS) location of the communication apparatus 600, a congestion level of a network traffic and a road traffic around the communication apparatus 600, a zone identifier (ID) indicating a geographical zone in which the communication apparatus 600 is located
As mentioned above, it is not clear how a SL UE should become power saving or operating in a power saving state, and how a SL UE to balance its power saving with performance requirement, for example, to transmit or receive certain types of sidelink signals. Hence, there is a need to address one or more of the above challenges and develop new communication apparatuses and communication methods for operating in a power saving state.
According to the present disclosure, a plurality of power saving states are defined to a SL UE, and the SL UE is configured to determine and operate in one of the plurality of power saving states. Each of the plurality of power save states are associated with different features/capability, featuring a different level of power saving. A power saving state can be configured or changed by either one of RRC configuration parameters, MAC CE, new SCI field/format via PSCCH signalling, or new DCI field/format via PDCCH signalling.
As shown in
The at least one transmitter 602 and the at least one receive receiver 604 may be included in a stand-alone module of the communication apparatus 600 to perform functions of both sending and receiving signals to and from another communication apparatus respectively. Such module may be referred to as a transceiver in various embodiments of the present disclosure.
It is appreciable to those skilled in the art that the arrangement of these functional modules is flexible and may vary depending on the practical needs and/or requirements. The data processing, storage and other relevant control apparatus can be provided on an appropriate circuit board and/or in chipsets.
The communication apparatus 600, when in operation, provides functions required for operating in a power saving state. For example, the communication apparatus 600 may be a sidelink UE or a VRU-UE. The circuitry 614 (the at least one controller 606 of the circuitry 614) may, in operation, determine one of a plurality of power saving states to operate in, and the transceiver (including the at least one radio transmitter 602 and the at least one radio receiver 604) may, in operation, transmit and/or receive at least one type of sidelink signals in response to determining the one of the plurality of power saving states. In an embodiment, the at least one transmission signal generator 608 and the at least one receive signal processor 610) may be respectively configured to transmit and receive the at least one type of sidelink signals such that the at least one radio transmitter 602 and the at least one radio receiver 604, or the transceiver (including the at least one radio transmitter 602 ad the at least one radio receiver 604) can transmit and/or receive the at least one type of sidelink signals when in operation.
In an embodiment, the transceiver may receive from another communication apparatus an indication signal relating to one of the plurality of power saving states, where the indication signal may include a request to operate in one of the plurality of power saving states, and the circuitry 614 (the at least one controller 606 of the circuitry 614) then determine to operate in the one of the plurality of power saving states in response to receiving the indication signal.
In another embodiment, when determining a power saving state to operate in, the circuitry 614 (the at least one controller 606 of the circuitry 614) may retrieve parameters relating to the communication apparatus 600, and the circuitry 614 (the at least one controller 606 of the circuitry 614) then determine to operate in one of the plurality of power saving states based on the retrieved parameters.
Yet in another embodiment, the transceiver may transmit assistance information comprising such parameters relating to the communication apparatus 600 to another communication apparatus prior to receiving from the other communication an indication signal relating to one of the plurality of power saving states from the other communication apparatus, for example, a power saving state that is suitable with balanced power saving and performance requirement determined based on the parameters, informing the communication apparatus to operate in that power saving state. The circuitry 614 (the at least one controller 606 of the circuitry 614) then determine to operate in the one of the plurality of power saving states in response to receiving the indication signal.
In another embodiment, the circuitry 614 of the communication apparatus 600 may identify one of the plurality of power saving states to operate in (or switch to), for example a preferred power saving state based on the parameters relating to the communication apparatus 600, and the transceiver may further transmit a request signal to another communication apparatus indicating a request to operate in (or switch to) the one of the plurality of power saving states. Subsequently, the transceiver may then receive a response signal from the other communication apparatus accepting the request and allowing the communication apparatus 600 to operate in that power saving state identified by the communication apparatus.
According to the present the disclosure, power saving states are (pre-)defined for a UE for different SL reception capabilities and thus respectively featuring different levels of power saving during operation.
A power saving state (e.g. one of states D1-D4) for a UE can be determined by the UE itself, a network or another SL UE for power saving purpose and/or system efficiency to ensure performance requirements. Additionally or alternatively, the power saving states for either SL reception or transmission can be additionally/separately defined to include/exclude other SL capabilities/features like full/partial sensing, reservation/pre-emption, monitoring/transmitting SLSS/PSBCH, PSFCH etc.
The power saving state could be configured/switched by using an indication signal for example as indication(s). Such indication signal may be one or a combination of the following:
Similarly,
According to the present disclosure, a UE can switch to operate from one power saving state to another by event-triggering. Such triggering event may be from the UE itself, another UE, a gNB or a network. In one embodiment, UE upper layer determines a preference to switch its power saving state to another power saving state, for example, to reduce power consumption or to have better performance (with increased capabilities). Such preference to operate in the other power saving state may be determined based on parameters and relevant factors relating to the UE.
If the UE is under a network coverage, it informs the network about its preferred/desirable power saving state. If the network agrees, the network will inform the UE about the switching of power saving state; otherwise, no switching occurs. On the other hand, if the UE is not under the network coverage or the network does not control the switching of power saving state of the UE, the UE is then configured to switch to tis preferred/desirable power saving state.
In addition to a request signal indicating a request to switch to a preferred power saving state of instead of the request signal, a UE may transmit assistance information comprising parameters (with relevant factors) relating to the UE to the network (or gNB).
In step 1302, the UE is configured to report its parameters and relevant factors to the network. In one embodiment, such parameters and relevant factors are included in UE assistance information transmitted to the network. In step 1304, the network is configured to evaluate the parameters and the relevant factors. In step 1306, the network is configured to determine if it is required for the UE to switch its power saving state. If it is determined by the network that a switch in the UE's power saving state is required, for example when it is determined by the network that a certain power saving state is more suitable for the UE to operate in (with balanced power saving and performance requirement) as compared to the current power saving state operated by the UE, step 1308 is carried out where the network is then configured to inform the UE to switch to the other power saving state, for example by sending to the UE an indication signal mentioned earlier to indicate the other power saving state; otherwise step 1310 is carried out. In step 1310, for example, it is determined that there is no need for the UE to switch, for example, there is no power saving state that is more suitable than the current power saving state, and the UE remains is operation under the current power saving state.
In various embodiments, a UE may be configured to determine to operate in (or switch to) a specific power saving state, or power saving state that supports or does not support certain features/functions. Similarly, an indication signal (for example RRC, PSCCH and PDCCH signals as shown in
For example, a UE may receive a signal to switch to a preferred power saving state D2, and if the UE is currently operating in power saving state D3, it would then switch to operate in power saving state D2. Alternatively, a UE may receive a signal to operate in a state that supports PSSCH, and therefore the UE may determine to operate in (or switch to) such power saving state. For example, if the UE is operating in state D3, upon receiving the signal, it would then switch to state D1 or D2. On the other hand, a UE may receive a signal to operate in a state that does not support PSSCH, and thus the UE may determine to operate in (or switch to) such power saving state. For example, if the UE is operating in state D1, upon receiving the signal, it would then switch to state D3 or D4.
As mentioned earlier, a SL UE could be (pre-)configured with a default/initial power saving state among a plurality of power saving states operable by the SL UE. When the SL UE is switched to a power saving state that is not its default/initial power saving state, a fallback timer, for example a timer-based fallback parameter, may be initiated and used to switch back to its default/initial power saving state once the fallback timer has expired. Such timer-based fallback parameter can be configured using one of a RRC signalling as a pattern/timer, or a MAC/PSCCH signalling similar to discontinuous reception (DRX).
Such default power saving state may be (pre-)configured or (pre-)defined by either specification (e.g. 3GPP), government regulators, or UE vendors. It is noted that the behaviours of different power saving states should be defined in 3GPP (RRC configuration, UE capabilities, etc.). The upper layer operation of which states to be implemented, and in what use case for a certain state to be implemented, should be up to country/region regulation or UE implementation and determination.
In an embodiment of the present disclosure, for a UE that supports reception of PSCCH and its features only such as PSCCH reception for sensing only, as shown in state D3 of
Further, if another SL UE which intends to send a SL message carried by a PSSCH to the SL UE with PSCCH sensing only, the another SL UE may need to send a standalone PSCCH to inform the SL UE to switch to other power saving states capable for PSSCH receiving. The standalone PSCCH may carry one or several bits in SCI to inform to switch to a certain power saving state or a state supporting the function (e.g. PSSCH reception).
In the following paragraphs, certain exemplifying embodiments are explained with reference to terms related to 5G core network and the present disclosure regarding communication apparatuses and methods for sidelink broadcast, namely:
In the present disclosure, the downlink control signal (information) related to the present disclosure may be a signal (information) transmitted through PDCCH of the physical layer or may be a signal (information) transmitted through a MAC Control Element (CE) of the higher layer or the RRC. The downlink control signal may be a pre-defined signal (information).
The uplink control signal (information) related to the present disclosure may be a signal (information) transmitted through PUCCH of the physical layer or may be a signal (information) transmitted through a MAC CE of the higher layer or the RRC. Further, the uplink control signal may be a pre-defined signal (information). The uplink control signal may be replaced with uplink control information (UCI), the 1st stage sidelink control information (SCI) or the 2nd stage SCI.
In the present disclosure, the base station may be a Transmission Reception Point (TRP), a clusterhead, an access point, a Remote Radio Head (RRH), an eNodeB (eNB), a gNodeB (gNB), a Base Station (BS), a Base Transceiver Station (BTS), a base unit or a gateway, for example. Further, in side link communication, a terminal may be adopted instead of a base station. The base station may be a relay apparatus that relays communication between a higher node and a terminal. The base station may be a roadside unit as well.
The present disclosure may be applied to any of uplink, downlink and sidelink. The present disclosure may be applied to, for example, uplink channels, such as PUSCH, PUCCH, and PRACH, downlink channels, such as PDSCH, PDCCH, and PBCH, and side link channels, such as Physical Sidelink Shared Channel (PSSCH), Physical Sidelink Control Channel (PSCCH), and Physical Sidelink Broadcast Channel (PSBCH).
PDCCH, PDSCH, PUSCH, and PUCCH are examples of a downlink control channel, a downlink data channel, an uplink data channel, and an uplink control channel, respectively. PSCCH and PSSCH are examples of a sidelink control channel and a sidelink data channel, respectively. PBCH and PSBCH are examples of broadcast channels, respectively, and PRACH is an example of a random access channel.
The present disclosure may be applied to any of data channels and control channels. The channels in the present disclosure may be replaced with data channels including PDSCH, PUSCH and PSSCH and/or control channels including PDCCH, PUCCH, PBCH, PSCCH, and PSBCH.
In the present disclosure, the reference signals are signals known to both a base station and a mobile station and each reference signal may be referred to as a Reference Signal (RS) or sometimes a pilot signal. The reference signal may be any of a DMRS, a Channel State Information-Reference Signal (CSI-RS), a Tracking Reference Signal (TRS), a Phase Tracking Reference Signal (PTRS), a Cell-specific Reference Signal (CRS), and a Sounding Reference Signal (SRS).
In the present disclosure, time resource units are not limited to one or a combination of slots and symbols, and may be time resource units, such as frames, superframes, subframes, slots, time slot subslots, minislots, or time resource units, such as symbols, Orthogonal Frequency Division Multiplexing (OFDM) symbols, Single Carrier-Frequency Division Multiplexing Access (SC-FDMA) symbols, or other time resource units. The number of symbols included in one slot is not limited to any number of symbols exemplified in the embodiment(s) described above, and may be other numbers of symbols.
The present disclosure may be applied to any of a licensed band and an unlicensed band.
The present disclosure may be applied to any of communication between a base station and a terminal (Uu-link communication), communication between a terminal and a terminal (Sidelink communication), and Vehicle to Everything (V2X) communication. The channels in the present disclosure may be replaced with PSCCH, PSSCH, Physical Sidelink Feedback Channel (PSFCH), PSBCH, PDCCH, PUCCH, PDSCH, PUSCH, and PBCH.
In addition, the present disclosure may be applied to any of a terrestrial network or a network other than a terrestrial network (NTN: Non-Terrestrial Network) using a satellite or a High Altitude Pseudo Satellite (HAPS). In addition, the present disclosure may be applied to a network having a large cell size, and a terrestrial network with a large delay compared with a symbol length or a slot length, such as an ultra-wideband transmission network.
An antenna port refers to a logical antenna (antenna group) formed of one or more physical antenna(s). That is, the antenna port does not necessarily refer to one physical antenna and sometimes refers to an array antenna formed of multiple antennas or the like. For example, it is not defined how many physical antennas form the antenna port, and instead, the antenna port is defined as the minimum unit through which a terminal is allowed to transmit a reference signal. The antenna port may also be defined as the minimum unit for multiplication of a precoding vector weighting.
The present disclosure can be realized by software, hardware, or software in cooperation with hardware. Each functional block used in the description of each embodiment described above can be partly or entirely realized by an LSI such as an integrated circuit, and each process described in the each embodiment may be controlled partly or entirely by the same LSI or a combination of LSIs. The LSI may be individually formed as chips, or one chip may be formed so as to include a part or all of the functional blocks. The LSI may include a data input and output coupled thereto. The LSI here may be referred to as an IC, a system LSI, a super LSI, or an ultra LSI depending on a difference in the degree of integration. However, the technique of implementing an integrated circuit is not limited to the LSI and may be realized by using a dedicated circuit, a general-purpose processor, or a special-purpose processor. In addition, a FPGA (Field Programmable Gate Array) that can be programmed after the manufacture of the LSI or a reconfigurable processor in which the connections and the settings of circuit cells disposed inside the LSI can be reconfigured may be used. The present disclosure can be realized as digital processing or analogue processing. If future integrated circuit technology replaces LSIs as a result of the advancement of semiconductor technology or other derivative technology, the functional blocks could be integrated using the future integrated circuit technology. Biotechnology can also be applied.
The present disclosure can be realized by any kind of apparatus, device or system having a function of communication, which is referred to as a communication apparatus.
The communication apparatus may comprise a transceiver and processing/control circuitry. The transceiver may comprise and/or function as a receiver and a transmitter. The transceiver, as the transmitter and receiver, may include an RF (radio frequency) module including amplifiers, RF modulators/demodulators and the like, and one or more antennas.
Some non-limiting examples of such a communication apparatus include a phone (e.g, cellular (cell) phone, smart phone), a tablet, a personal computer (PC) (e.g, laptop, desktop, netbook), a camera (e.g, digital still/video camera), a digital player (digital audio/video player), a wearable device (e.g, wearable camera, smart watch, tracking device), a game console, a digital book reader, a telehealth/telemedicine (remote health and medicine) device, and a vehicle providing communication functionality (e.g., automotive, airplane, ship), and various combinations thereof.
The communication apparatus is not limited to be portable or movable, and may also include any kind of apparatus, device or system being non-portable or stationary, such as a smart home device (e.g, an appliance, lighting, smart meter, control panel), a vending machine, and any other “things” in a network of an “Internet of Things (IoT)”.
The communication may include exchanging data through, for example, a cellular system, a wireless LAN system, a satellite system, etc., and various combinations thereof.
The communication apparatus may comprise a device such as a controller or a sensor which is coupled to a communication device performing a function of communication described in the present disclosure. For example, the communication apparatus may comprise a controller or a sensor that generates control signals or data signals which are used by a communication device performing a communication function of the communication apparatus.
The communication apparatus also may include an infrastructure facility, such as a base station, an access point, and any other apparatus, device or system that communicates with or controls apparatuses such as those in the above non-limiting examples.
It will be appreciated by a person skilled in the art that numerous variations and/or modifications may be made to the present disclosure as shown in the specific embodiments without departing from the spirit or scope of the disclosure as broadly described. The present embodiments are, therefore, to be considered in all respects illustrative and not restrictive.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10202100539Y | Jan 2021 | SG | national |
| 10202103195T | Mar 2021 | SG | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/SG2021/050699 | 11/15/2021 | WO |
