CN116746221A - Communication device and communication method for operating in power saving state - Google Patents

Abstract

The present disclosure provides a communication apparatus and a communication method for operating in a power saving state. The communication device includes circuitry to determine one of a plurality of power saving states to operate under; and a transceiver that transmits and/or receives at least one type of side link signal in response to determining one of the plurality of power saving states.

Description

Communication device and communication method for operating in power saving state

Technical Field

The following disclosure relates to a communication apparatus and a communication method for operating in a power saving state, and more particularly to a side link User Equipment (UE).

Background

Vehicle-to-anything (V2X) communication allows vehicles to interact with public roads and other road users, and is therefore considered a key factor in implementing autonomous vehicles.

To accelerate this process, the third generation partnership project (3 GPP) is discussing V2X communications (interchangeably referred to as NR V2X communications) based on the 5G new radio access technology (NR) to determine a technical solution for advanced V2X services by which vehicles (i.e., interchangeably referred to as V2X application-enabled communication devices or User Equipment (UEs)) can exchange their own status information with other nearby vehicles, infrastructure nodes, and/or pedestrians via a Side Link (SL). The status information includes information about location, speed, heading, etc.

According to the determination in the version 17 (Rel-17) V2X Work Item Description (WID) (RP-202846), power saving enables battery-limited UEs to perform side link operations in a power efficient manner. The Rel-16 NR side link is designed based on the assumption that the UE is "always on" when operating the side link, e.g., only focusing on UEs installed in vehicles with sufficient battery capacity. For Vulnerable Road Users (VRUs) in V2X use cases and for public safety and UEs in business use cases where power consumption in the UE needs to be minimized, a power saving solution in Rel-17 is needed.

Furthermore, in the RANs 1#103-e conference, two UE reception types (i.e., with or without reception capability) have been summarized for evaluation and power saving features in Rel-17.

In particular, it is not clear how a SL UE should become power efficient, and how the SL UE balances its power saving and performance requirements.

Accordingly, there is a need to address one or more of the above challenges and develop new communication devices 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.

Disclosure of Invention

One non-limiting and exemplary embodiment helps provide a communication apparatus and method for utilizing SL-RSRP in V2X resource sensing & selection.

In a first aspect, the present disclosure provides a communication apparatus comprising: circuitry that determines one of a plurality of power saving states to operate under; and a transceiver that transmits and/or receives at least one type of side link signal among the side link signals in response to determining 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 thereunder; and transmitting and/or receiving at least one type of side link signal in response to determining one of the plurality of power saving states.

It should be noted that general or specific embodiments may be implemented as a system, method, integrated circuit, computer program, storage medium, or any selective combination thereof.

Additional benefits and advantages of the disclosed embodiments will become apparent from the description and drawings. Benefits and/or advantages may be obtained by various embodiments and features of the specification and drawings alone, which do not require all embodiments and features to be provided in order to obtain one or more of such benefits and/or advantages.

Drawings

Embodiments of the present disclosure will be better understood and readily apparent to those of ordinary skill in the art from the following written description, taken by way of example only, in conjunction with the accompanying drawings, in which:

fig. 1 shows an exemplary 3GPP NR-RAN architecture.

Fig. 2 depicts a schematic diagram of the functional division between NG-RAN and 5 GC.

Fig. 3 depicts a sequence diagram of a Radio Resource Control (RRC) connection setup/reconfiguration procedure.

Fig. 4 depicts a schematic diagram showing usage scenarios of enhanced mobile broadband (eMBB), large-scale machine type communication (mctc), and ultra-reliable low latency communication (URLLC).

Fig. 5 shows a block diagram of an exemplary 5G system architecture for V2X communication in a non-roaming scenario.

Fig. 6 shows a schematic example of a communication apparatus according to various embodiments. According to various embodiments of the present disclosure, a communication device may be implemented as a UE or a gNB/base station and configured for vulnerable road users to transmit a first signal at periodic transmission time intervals.

Fig. 7 illustrates a flow chart showing a communication method for a vulnerable road user to transmit a first signal at periodic transmission time intervals, in accordance with various embodiments of the present disclosure.

Fig. 8 depicts a flowchart showing four power saving state configurations for SL signal reception according to an embodiment of the present disclosure.

Fig. 9-11 depict three flowcharts, respectively, of using an indication signal to configure a UE to operate in one of a plurality of power saving states, in accordance with various embodiments of the present disclosure.

Fig. 12 depicts a flowchart showing a process of switching from a current power saving state to a preferred power saving state in accordance with an embodiment of the present disclosure.

Fig. 13 depicts a flowchart that shows a process of indicating, by another communication device, a handoff from a power saving state currently operated by the communication device to another power saving state, in accordance with an embodiment of the present disclosure.

Fig. 14 depicts a flowchart that shows a process of operating in a default power saving state, according to an embodiment of the present disclosure.

Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures, block diagrams, or flowcharts may be exaggerated relative to other elements to help improve understanding of the present embodiments.

Detailed Description

Some embodiments of the present disclosure will be described, by way of example only, with reference to the accompanying drawings. Like reference numbers and characters in the drawings refer to like elements or equivalents.

The 3GPP has been working on developing the next version of the fifth generation cellular technology (abbreviated 5G) including developing new radio access technologies (NR) operating in the frequency range up to 100 GHz. The first version of the 5G standard was completed at the end of 2017, which allowed for experimental and commercial deployment of smartphones conforming to the 5G NR standard. The second edition of 5G standards is completed in month 6 of 2020, which further extends 5G coverage to new services, spectrum and deployments such as unlicensed spectrum (NR-U), non-public networks (NPN), time-sensitive networks (TSN) and cellular V2X.

The overall system architecture assumes, among other things, the NG-RAN (next generation radio access network) containing the gNB, providing NG radio access user plane (SDAP/PDCP/RLC/MAC/PHY) and control plane (RRC) protocol termination to the UE. The gNBs are interconnected with each other through an Xn interface. The gNB is also connected to the NGC (next generation core) through a Next Generation (NG) interface, more specifically to the AMF (Access and mobility management function) through a NG-C interface (e.g., the specific core entity that performs the AMF), and to the UPF (user plane function) through a NG-U interface (e.g., the specific core entity that performs the UPF). The NG-RAN architecture is shown in fig. 1 (see e.g., 3GPP TS 38.300v16.3.0).

The user plane protocol stack of NR (see e.g. 3gpp TS 38.300, section 4.4.1) comprises 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) sub-layers, which terminate in a gNB on the network side. Furthermore, a new access layer (AS) sub-layer (SDAP, service data adaptation protocol) is introduced above PDCP (see e.g. clause 6.5 of 3gpp TS 38.300). A control plane protocol stack is also defined for NR (see e.g. TS 38.300, section 4.4.2). The sub-clause 6 of TS 38.300 gives an overview of layer 2 functionality. The functions of PDCP, RLC and MAC sublayers are listed in sections 6.4, 6.3 and 6.2 of TS 38.300, respectively. The 7 th sub-clause of TS 38.300 lists the functionality of the RRC layer.

For example, the medium access control layer handles logical channel multiplexing and scheduling related functions including processing of different parameter sets.

The physical layer (PHY) is responsible for, for example, coding, PHY hybrid automatic repeat request (HARQ) processing, modulation, multi-antenna processing, and mapping of signals to 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. The physical channels correspond to a set of time-frequency resources for transmission of a particular transport channel, and each transport channel is mapped to a corresponding physical channel. For example, 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 side link shared channel), PSCCH (physical side link control channel) and physical side link feedback channel (PSFCH) for a Side Link (SL).

SL supports UE-to-UE direct communication using SL resource allocation patterns, physical layer signals/channels, and physical layer procedures. Two SL resource allocation modes are supported: (a) mode 1, wherein SL resource allocation is provided by the network; and (b) mode 2, wherein the UE decides on SL transmission resources in the resource pool(s).

The PSCCH indicates the resources and other transmission parameters used by the UE for the PSSCH. The PSCCH transmission is associated with a demodulation reference signal (DM-RS). The PSSCH transmits a Transport Block (TB) of the data itself, control information and Channel State Information (CSI) feedback trigger for the HARQ process, and the like. There are at least 6 Orthogonal Frequency Division Multiplexing (OFDM) symbols within a slot for PSSCH transmission. The PSSCH transmission is associated with a DM-RS and can be associated with a phase tracking reference signal (PT-RS).

The PSFCH carries HARQ feedback on the SL from the UE that is the intended recipient of the PSSCH transmission to the UE performing the transmission. The PSFCH sequence is transmitted in one PRB repeated on two OFDM symbols near the end of the SL resource in the slot.

The SL synchronization signals include SL primary synchronization signals and SL secondary synchronization signals (S-PSS, S-SSS), each occupying 2 symbols and 127 subcarriers. For normal and extended cyclic prefix cases, the physical side link broadcast channel (PSBCH) occupies 9 and 5 symbols, respectively, including an associated demodulation reference signal (DM-RS).

Regarding the physical layer procedure of HARQ feedback of the side link, SL HARQ feedback uses PSFCH and can operate with one of two options. In one option, which may be configured for both unicast and multicast, the PSFCH sends either an ACK or NACK using resources dedicated to a single PSFCH sending UE. In another option that may be configured for multicasting, the PSFCH transmits a NACK on a resource that may be shared by multiple PSFCH transmitting UEs, or does not transmit a PSFCH signal.

In SL resource allocation mode 1, a UE receiving PSFCH may report SL HARQ feedback to the gNB via PUCCH or PUSCH.

With respect to the physical layer process of power control of the side link, for intra-coverage operation, the power spectral density of the SL transmission may be adjusted based on the pathloss of the gNB; while for unicast, the power spectral density of some SL transmissions may be adjusted based on the path loss between two communicating UEs.

Regarding the physical layer procedure of CSI reporting, for unicast, a channel state information reference signal (CSI-RS) is supported for CSI measurement and reporting in a side link. CSI reports are carried in the SL MAC CE.

For the measurement of the contralateral link, the following UE measurement quantities (metrics) are supported:

● PSBCH reference signal received power (PSBCH RSRP);

● PSSCH reference Signal received Power (PSSCH-RSRP);

● PSCCH reference signal received power (PSCCH-RSRP);

● A side link received signal strength indicator (SL RSSI);

● Side link channel occupancy (SL CR);

● Side link channel busy rate (SL CBR).

The use case/deployment scenario of NR may include enhanced mobile broadband (eMBB), ultra-reliable low latency communication (URLLC), large-scale machine type communication (mMTC), which differ in data rate, latency, and coverageIs not limited. For example, an eMBB is expected to support a peak data rate (20 Gbps downlink and 10Gbps uplink) and a data rate of approximately three times the user experience of the data rate provided by IMT-Advanced. On the other hand, in the case of URLLC, the delay is 0.5ms for both ultra low latency (UL and DL for user plane) and high reliability (1-10 within 1 ms) ^-5 ) More stringent requirements are imposed. Finally, mctc may preferably require a high connection density (1,000,000 devices/km in urban environments) ² ) A large coverage in harsh environments, and a very long life battery (15 years) for low cost equipment.

Thus, an OFDM parameter set (e.g., subcarrier spacing, OFDM symbol duration, cyclic Prefix (CP) duration, number of symbols per scheduling interval) that is suitable for one use case may not work well for another use case. For example, a low latency service may preferably require shorter symbol duration (and thus larger subcarrier spacing) and/or fewer symbols per scheduling interval (also referred to as TTI) than an emtc 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 preserve similar CP overhead. NR may support more than one subcarrier spacing value. Accordingly, subcarrier spacings of 15kHz, 30kHz, 60kHz, … … are currently being considered. Symbol duration T _u And subcarrier spacing Δf is calculated by the formula Δf=1/T _u Directly related. In a similar manner as in the LTE system, the term "resource element" may be used to denote the smallest resource unit consisting of one subcarrier for one OFDM/SC-FDMA symbol length.

In the new radio system 5G-NR, for each parameter set and carrier, a resource grid of subcarriers and OFDM symbols is defined for uplink and downlink, respectively. Each element in the resource grid is referred to as a resource element and is identified based on a frequency index in the frequency domain and a symbol position in the time domain (see 3GPP TS 38.211v16.3.0).

Fig. 2 shows the functional division between NG-RAN and 5 GC. The NG-RAN logical node is a gNB or a NG-eNB. The 5GC has logical nodes AMF, UPF, and SMF.

Specifically, the gNB and ng-eNB host (host) the following main functions:

radio resource management functions such as radio bearer control, radio admission control, connection mobility control, dynamic allocation (scheduling) of resources to UEs in both uplink and downlink;

IP header compression, encryption of data and integrity protection;

-selection of an AMF at UE attach when the route to the AMF cannot be determined from the information provided by the UE;

-routing of user plane data to UPF(s);

-routing control plane information to the AMF;

-connection establishment and release;

-scheduling and transmission of paging messages;

scheduling and transmission of system broadcast information (originating from AMF or OAM);

-measurement and measurement report configuration for mobility and scheduling;

-a transmission level packet marking in the uplink;

-session management;

-support for network slicing;

QoS flow management and mapping to data radio bearers;

-support for UE in rrc_inactive state;

-a distribution function of NAS messages;

-radio access network sharing;

-a dual connection;

-close interworking between NR and E-UTRA.

The access and mobility management function (AMF) hosts the following main functions:

-non access stratum, NAS, signaling termination;

NAS signaling security;

-access stratum, AS, security control;

inter-core network, CN, node signaling for mobility between 3GPP access networks; idle mode UE reachability (including control and execution of paging retransmissions);

-registration area management;

-support for intra-and inter-system mobility;

-access authentication;

-access authentication including a check of roaming rights;

mobility management control (subscription and policy);

-support for network slicing;

session management function, SMF, selection.

Furthermore, the user plane function UPF hosts the following main functions:

-an anchor point (if applicable) for intra-RAT/inter-RAT mobility;

-an external PDU session point interconnected with the data network;

-packet routing & forwarding;

-packet inspection and user plane part of policy rule enforcement;

-a service usage report;

-an uplink classifier supporting routing of traffic flows to the data network;

-a branching point supporting a multi-host PDU session;

QoS treatment of the user plane, e.g. packet filtering, gating, UL/DL rate enforcement;

uplink traffic authentication (SDF to QoS flow mapping);

-downlink packet buffering and downlink data notification triggering.

Finally, the session management function SMF hosts the following main functions:

-session management;

-UE IP address allocation and management;

-selection and control of UP functions;

-configuring traffic steering on the user plane function UPF to route traffic to the correct destination;

-a policy enforcement and QoS control part;

-downlink data notification.

Fig. 3 shows some interactions between UE, gNB and AMF (5 GC entity) in the context of the transition of the UE of NAS part from rrc_idle to rrc_connected (see TS 38.300v 16.3.0). The transition steps are as follows:

The ue requests to establish a new connection from rrc_idle.

The 2/2a. GNB completes the RRC establishment procedure.

Note that: the context of the gNB refusing the request is as follows.

3. A first NAS message from the UE piggybacked in rrcsetup complete is sent to the AMF.

4/4a/5/5a additional NAS messages may be exchanged between the UE and the AMF, see TS 23.502.

The amf prepares UE context data (including PDU session context, security keys, UE radio capability, UE security capability, etc.) and sends it to the gNB.

gNB activates AS security with the UE.

The gNB performs reconfiguration to set SRB2 and DRB.

The gNB notifies the completion of the AMF setup procedure.

RRC is a higher layer signaling (protocol) for UE and gNB configuration. In particular, this transition involves the AMF preparing and sending UE context data (including, e.g., PDU session context, security key, UE radio capability, UE security capability, etc.) to the gNB along with an initial context setup request (INITIAL CONTEXT SETUP REQUEST). Then, the gNB activates AS security with the UE by the gNB sending a SecurityModeCommand message to the UE and by the UE responding to the gNB with a SecurityModeCommand message. Thereafter, the gNB performs the reconfiguration of the setup signaling radio bearers 2, SRB2 and data radio bearer(s), DRB(s) by sending a RRCRECONfigure message to the UE and in response receiving RRCRECONfigure complete from the UE by the gNB. For signaling only connections, the steps related to rrcrecon configuration are skipped since SRB2 and DRB are not set. Finally, the gNB notifies the AMF setup process of completion through the initial context setup response.

Fig. 4 shows some of the use cases of 5G NR. In the third generation partnership project new radio (3 GPP NR), three use cases are being considered, which are expected to support various services and applications of IMT-2020. The specification of phase 1 of enhanced mobile broadband (eMBB) has been completed. In addition to further extending the eMBB support, current and future work will also involve standardization of ultra-reliable low latency communications (URLLC) and large-scale machine type communications. Fig. 4 shows some examples of contemplated use scenarios for IMT in 2020 and later (see, e.g., ITU-R m.2083 fig. 2).

The URLLC use case places stringent demands on capabilities such as throughput, latency and availability, and is envisioned as one of the contributors to future vertical applications such as wireless control of industrial manufacturing or production processes, telemedicine surgery, distribution automation in smart grids, traffic safety, etc. The ultra-reliability of URLLC will be supported by determining the technology that meets the requirements specified by TR 38.913. For NR URLLC in release 15, the key requirements include a target user plane delay of 0.5ms for UL (uplink) and 0.5ms for DL (downlink). A typical URLLC requirement for one transmission of packets is that the BLER (block error rate) for a packet size of 32 bytes is 1E-5, the user plane delay is 1ms.

From the physical layer point of view, reliability can be improved in a number of possible ways. The current scope of improving reliability includes defining separate CQI tables for URLLC, more compact DCI formats, repetition of PDCCH, etc. However, as NR becomes more stable and evolving (for NRURLLC key requirements), the range of implementation of super-reliability may be widened. Specific examples of NR URLLC in Rel 15 include augmented reality/virtual reality (AR/VR), electronic health, electronic security, and mission critical applications.

Further, technical enhancements targeted by NR URLLC are aimed at latency improvements and reliability improvements. The technical enhancements for latency improvement include configurable parameter sets, non-slot-based scheduling with flexible mapping, unlicensed (configured grant) uplink, slot-level repetition of data channels, and downlink preemption. Preemption means that the transmission that has allocated resources is stopped and the allocated resources are used for another transmission that is requested later but has a lower latency/higher priority requirement. Thus, an already authorized transmission is preempted by a later transmission. Preemption is applicable regardless of the particular service type. For example, a transmission of service type a (URLLC) may be preempted by a transmission of service type B (such as eMBB). Technical enhancements for reliability improvement include a dedicated CQI/MCS table for the 1E-5 target BLER.

Use cases of mctc (large scale machine type communication) are characterized by a very large number of connected devices, typically transmitting relatively small amounts of non-delay sensitive data. The device needs to be low cost and have a long battery life. From the NR point of view, utilizing a very narrow portion of bandwidth is one possible solution from the UE point of view that may achieve power savings and extend battery life.

As described above, the range of reliability of NR is expected to become wider. A key requirement necessary for all cases, especially URLLC and mctc, is high or ultra-reliability. Various mechanisms may be considered to improve reliability from a radio perspective and a network perspective. In general, there are several key potential areas that can help to improve reliability. Among these areas are compact control channel information, data/control channel repetition, and diversity with respect to frequency, time, and/or spatial domains. Regardless of the particular communication scenario, these areas are generally applicable to reliability.

For NR URLLC, more use cases with more stringent requirements have been determined, such as factory automation, transportation industry, and power distribution, including factory automation, transportation industry, and power distribution. The more stringent requirements are higher reliability (up to 10 ^-6 Hierarchy), higher availability, packet sizes up to 256 bytes, time synchronization down to about a few mus (where the value may be 1 or a few mus depending on the frequency range), and short delay of about 0.5 to 1ms depending on the use case, in particular a target user plane delay of 0.5 ms.

Further, for NRURLLC, a number of technical enhancements from the physical layer perspective have been determined. Among these technical enhancements are PDCCH (physical downlink control channel) enhancements related to compact DCI, PDCCH repetition, increased PDCCH monitoring. Further, UCI (uplink control information) enhancement is related to enhanced HARQ (hybrid automatic repeat request) and CSI feedback enhancement. Further, PUSCH enhancements associated with minislot level hopping and retransmission/repetition enhancements are also determined. The term "minislot" refers to a Transmission Time Interval (TTI) that includes a fewer number of symbols than a slot (a slot comprising 14 symbols).

The 5G QoS (quality of service) model is based on QoS flows and supports both QoS flows requiring guaranteed flow bit rates (GBR QoS flows) and QoS flows not requiring guaranteed flow bit rates (non-GBR QoS flows). At the NAS level, qoS flows are therefore the finest granularity of QoS differentiation in PDU sessions. The QoS flow is identified in the PDU session by a QoS Flow ID (QFI) carried in an encapsulation header on the NG-U interface.

For each UE, the 5GC establishes one or more PDU sessions. For each UE, the NG-RAN establishes at least one Data Radio Bearer (DRB) with the PDU session and may then configure additional DRB(s) for QoS flow(s) of the PDU session (when it is decided by the NG-RAN), e.g., as described above with reference to fig. 3. The NG-RAN maps packets belonging to different PDU sessions to different DRBs. NAS-level packet filters in UE and 5GC associate UL and DL packets with QoS flows, while AS-level mapping rules in UE and NG-RAN associate UL and DL QoS flows with DRBs.

Fig. 5 shows a 5G NR non-roaming reference architecture (see TS 23.287v16.4.0, section 4.2.1.1). An Application Function (AF), e.g. an external application server hosting a 5G service, is exemplarily depicted in fig. 4 interacting with the 3GPP core network in order to provide services, e.g. supporting the impact of applications on traffic routing, access Network Exposure Functions (NEF) or interacting with policy frameworks for policy control (see policy control function, PCF), e.g. QoS control. Based on the operator deployment, application functions deemed trusted by the operator may be allowed to interact directly with related network functions. The operator does not allow application functions that directly access the network functions to interact with the relevant network functions via the NEF using the external exposure framework.

Fig. 5 shows further functional units of the 5G architecture for V2X communication, namely Unified Data Management (UDM), policy Control Function (PCF), network Exposure Function (NEF), application Function (AF), unified Data Repository (UDR), access and mobility management function (AMF), session Management Function (SMF) and User Plane Function (UPF) in 5GC, AS well AS V2X application server (V2 AS) and Data Network (DN), e.g. operator services, internet access or third party services. All or part of the core network functions and application services may be deployed and run in a cloud computing environment.

According to European Telecommunications Standards Institute (ETSI) Technical Report (TR) 103 300, the abstract flow for the V2X use case for Vulnerable Road Users (VRUs) includes:

detection of the presence of a vru. The alternative scheme is as follows:

VRU self-localization, where the VRU has sensors and potentially other sources, allowing it to determine its own attributes, including its location and speed;

another road user (e.g., V-ITS-S) detects and tracks the VRU; and

roadside equipment connected to the R-ITS-S or central ITS-S detects and tracks the VRU.

2. Evaluate whether the VRU is facing the potential risk of other road users and should send VRU location and dynamics. Any party may send information about the VRU that it knows. The information about the VRU should be filtered and sent only according to the message trigger condition. The potential risk of other road users depends on, among other things, the following conditions:

Road layout;

dynamic of VRU and other road users; and

traffic signal status (if relevant) for both VRU and vehicle and compliance with traffic lights.

3. An evaluation of the secure messaging environment, in particular whether the VRU is part of a cluster, determines whether the VRU' S own ITS-S should be sent.

4. Information about the risky VRUs is sent. The alternative scheme is as follows:

the VRU sends self status (ego-status) information;

the VRU cluster leader sends cluster information; and

V-ITS-S, R-ITS-S, C-ITS-S or other road users send information about the VRU in case of potential risk.

5. And (5) risk assessment. The phase (receiver) includes:

fusing the sensor data with observed information transmitted by other road users to construct a local dynamic map with information about the road users' location, speed and potentially other data (e.g., intent); and

assessment of risk based on estimated trajectories and speeds of different road users.

6. A warning or action to protect a VRU, comprising:

warning of the device carrier (VRU or any other road user);

sending collision alerts to other road users; and

Action taken in the case of an autonomous vehicle.

As previously mentioned, the most fundamental step for the safety considerations of a VRU is the detection of the presence of the VRU. It is currently not clear when a VRU-UE should send its SL broadcast signal and a security message to indicate its presence. It is also noted that in LTE and NR uplink and downlink (Uu), DRX is used for power saving purposes. The VRU-UE only needs to wake up the DRX on duration to monitor the possible PDCCH and perform a potential transmission. On this basis, the UE with SL capability should reduce the wake-up time by using the DRX feature as much as possible to achieve the purpose of power saving.

In the various embodiments below, road users of the following types are considered Vulnerable Road Users (VRUs) according to the classification in annex 1 of ETSI TR 103 300 and regulations (EU) 168/2013[ i.8 ]:

pedestrian (including children, elderly, joggers).

Emergency rescue personnel, security personnel, road workers.

Animals such as horses, dogs, etc., and related wild animals (see notice below).

Wheelchair user, stroller.

Skaters, skateboards, seigav possibly equipped with electric motors.

Bicycles and electric bicycles with a speed limit of 25km/h (electric bicycle, class L1e-A [ i.8 ]).

High-speed electric bicycles with speeds higher than 25km/h, type L1e-B [ i.8].

Powered two-wheel vehicles (PTW), scooters (scooters), class L1e [ i.8].

PTW, motorcycle, class L3e [ i.8];

PTW, tricycle, L2e, L4e and L5e class [ i.8] with speed limit of 45 km/h;

PTW, quadricycle, L5e and L6e class [ i.8] with speed limit of 45 km/h.

Notice of: the related wild animals only refer to those related to other road users (VRU, vehicle)

Animals that constitute a safety risk

In various embodiments below, a communication device may be referred to as a side link UE. The sidelink UE may transmit and/or receive sidelink signals, such as a Physical Sidelink Control Channel (PSCCH), a Physical Sidelink Shared Channel (PSSCH), a sidelink synchronization block (S-SSB), a Physical Sidelink Feedback Channel (PSFCH), first and second order Sidelink Control Information (SCI), a downlink control indication signal, a radio resource control signal, a Medium Access Control (MAC) Control Element (CE), a Radio Resource Control (RRC) signal, a Physical Downlink Control Channel (PDCCH), a sidelink synchronization signal (SLSS), a Physical Sidelink Broadcast Channel (PSBCH), and a Physical Sidelink Feedback Channel (PSFCH).

According to the present disclosure, a communication device may be configured to operate in a power saving state or to determine to operate in a power saving state. The power saving state may be one of a plurality of power saving states in which the communication device is operable. Each of the plurality of power saving states corresponds to a different feature/capability featuring a different power saving level during operation.

In various embodiments, where a communication device may refer to a Side Link (SL) User Equipment (UE), another communication device may communicate with the side link UE by sending and/or receiving side link signals, the other communication device being one of: (i) A base station (gNodeB or gNB) or a cellular network, wherein a sidelink UE is located within the network coverage of the base station or the cellular network, and (ii) another sidelink UE, whether or not both the sidelink UE and the other sidelink UE are within the network coverage of the base station.

In various embodiments, the default power saving state or the initial power saving state may be one of a plurality of power saving states (pre) configured to be operated by the communication device. Such default/initial power saving state may be the most power saving state, the most power consuming state, or a preferred/suitable power saving state determined by the communication device or another communication device (e.g., a gNB, another SL UE) based on current operating conditions and parameters or any other state. Such default power saving state may also be (pre) configured or (pre) defined by any of the specifications (e.g. 3GPP specifications), government regulatory authorities or UE suppliers.

In various embodiments, the term "state" in the power saving state may be used interchangeably with "mode," scheme, "" type, "and" level.

In various embodiments, parameters related to the communication device may refer to relevant factors considered and used to determine a power saving state to operate, such as a transmission/reception priority of the communication device, a speed at which the communication device is moving, a type of communication device, a type of vehicle (e.g., train, bus, truck, car, bicycle), a Global Navigation Satellite System (GNSS) location of the communication device 600, a congestion level of network traffic and road traffic around the communication device 600, and an area Identifier (ID) indicating a geographic area in which the communication device 600 is located.

As mentioned above, it is not clear how a SL UE should become power-saving or operate in a power-saving state, and how the SL UE balances its power-saving and performance requirements, e.g. to send or receive certain types of side link signals. Accordingly, there is a need to address one or more of the above challenges and develop new communication devices and communication methods for operating in a power saving state.

According to the present disclosure, a plurality of power saving states are defined for a SL UE, and the SL UE is configured to determine and operate under one of the plurality of power saving states. Each of the plurality of power saving states is associated with a different feature/capability featuring a different power saving level. The power saving state may be configured or changed by one of an RRC configuration parameter, a MAC CE, a new SCI field/format via PSCCH signaling, or a new DCI field/format via PDCCH signaling.

As shown in fig. 6, communication device 600 may include circuitry 614, at least one radio transmitter 602, at least one radio receiver 604, and at least one antenna 612 (only one antenna is depicted in fig. 6 for purposes of illustration for simplicity). The circuitry 614 may include at least one controller 606 for software and hardware-assisted execution of tasks that the at least one controller 606 is designed to perform, including controlling communication with one or more other communication devices in the wireless network. The circuit 614 may also include at least one transmit signal generator 608 and at least one receive signal processor 610. The at least one controller 606 may control the at least one transmit signal generator 608 to generate signals (e.g., side link/uplink/downlink signals) to be transmitted to one or more other communication devices (e.g., peer to peer communication devices) via the at least one radio transmitter 602 and the at least one receive signal processor 610 to process signals (e.g., side link/uplink/downlink signals) received from the one or more other communication devices via the at least one radio receiver 604 under the control of the at least one controller 606. The at least one transmit signal generator 608 and the at least one receive signal processor 610 may be separate modules of the communication device 600 that communicate with the at least one controller 606 for the above-described functions, as shown in fig. 6. Alternatively, at least one transmit signal generator 608 and at least one receive signal processor 610 may be included in at least one controller 606. In various embodiments, the at least one radio transmitter 602, the at least one radio receiver 604, and the at least one antenna 612 may be controlled by the at least one controller 606 when in operation.

The at least one transmitter 602 and the at least one receiver 604 may be included in separate modules of the communication device 600 to perform the functions of both transmitting signals to and receiving signals from another communication device, respectively. In various embodiments of the present disclosure, such a module may be referred to as a transceiver.

Those skilled in the art will appreciate that the arrangement of these functional modules is flexible and may vary according to actual needs and/or requirements. The data processing, storage and other associated control means may be provided in a suitable circuit board and/or chipset.

The communication device 600 provides functions required for operation in a power saving state. For example, the communication device 600 may be a sidelink UE or a VRU-UE. The circuit 614 (at least one controller 606 of the circuit 614) may determine that one of a plurality of power saving states is to be operated under it, and the transceiver (including the at least one radio transmitter 602 and the at least one radio receiver 604) may transmit and/or receive at least one type of side link signal in response to determining the one of the plurality of power saving states. In an embodiment, the at least one transmit signal generator 608 and the at least one receive signal processor 610 may be configured to transmit and receive, respectively, at least one type of side link signal such that the at least one radio transmitter 602 and the at least one radio receiver 604 or transceiver (including the at least one radio transmitter 602 and the at least one radio receiver 604) may transmit and/or receive, in operation, the at least one type of side link signal.

In an embodiment, the transceiver may receive an indication signal associated with one of a plurality of power saving states from another communication device, wherein the indication signal may include a request to operate in the one of the plurality of power saving states, and the circuit 614 (the at least one controller 606 of the circuit 614) then determines 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 under, the circuit 614 (at least one controller 606 of the circuit 614) may retrieve parameters related to the communication device 600, and the circuit 614 (at least one controller 606 of the circuit 614) then determines to operate under one of the plurality of power saving states based on the retrieved parameters.

In yet another embodiment, the transceiver may send auxiliary information including parameters related to the communication device 600 to another communication device before receiving an indication signal from the other communication related to one of a plurality of power save states from the other communication device (e.g., a power save state that is appropriate for balanced power save and performance requirements based on the parameters) to inform the communication device to operate in the power save state. The circuit 614 (at least one controller 606 of the circuit 614) then determines to operate in one of a plurality of power saving states in response to receiving the indication signal.

In another embodiment, the circuitry 614 of the communication device 600 may identify one of the plurality of power saving states to operate under (or switch to) based on a parameter associated with the communication device 600, e.g., a preferred power saving state, and the transceiver may also send a request signal to another communication device indicating a request to operate under (or switch to) one of the plurality of power saving states. Subsequently, the transceiver may then receive a response signal from another communication device that accepts the request and allows communication device 600 to operate in the power saving state identified by the communication device.

Fig. 7 illustrates a flow chart showing a communication method 700 for operating in a power saving state according to various embodiments of the present disclosure. In step 702, one of a plurality of power saving states is determined. In step 704, at least one type of side link signal is transmitted and/or received in response to determining one of a plurality of power saving states.

According to the present disclosure, power saving states are (pre) defined for the UE for different SL reception capabilities and are thus characterized by different power saving levels during operation, respectively. Fig. 8 depicts a flowchart 800 showing four power saving state configurations (states D1-D4) for SL signal reception according to an embodiment of the present disclosure. The power saving states (states D1-D4) and their corresponding configurations may be (pre) defined as follows:

State D1: the UE supports receiving all types of SL signals and characteristics thereof;

state D2: the UE only supports the reception of PSCCH and its features such as PSCCH sensing, PSCCH reception and decoding, and does not support the reception of additional features such as SLSS/PSBCH when power saving is not needed;

state D3: the UE only supports the reception of PSCCH and its features, such as PSCCH reception for sensing only, PSSCH reception is not allowed when the UE performs sensing of resource selection only;

and

state D4: the UE does not perform any type of reception of the side chain signal, but performs only a transmission operation.

The power saving state of the UE (e.g., one of states D1-D4) may be determined by the UE itself, the network, or another SL UE for power saving purposes and/or system efficiency to ensure performance requirements. Additionally or alternatively, the power saving state of SL reception or transmission may be additionally/individually defined as including/excluding other SL capabilities/features such as full/partial sensing, reservation/preemption, monitoring/transmitting SLSS/PSBCH, PSFCH, etc.

The power saving state may be configured/switched by using the indication signal, e.g. as indication(s). The indication signal may be one or a combination of the following:

RRC configuration from upper layers (e.g., UE itself or from the network). This signaling may be implemented by a new RRC parameter SwitchPowerSavingState and is defined as SEQUENCE of state indexes or ENUMERATED of all states;

MAC CE, e.g., a new MAC CE with a new index for indicating the target power saving state;

the first stage SCI of the PSCCH via PSCCH signaling in a separate PSCCH or a PSCCH with dummy (dummy) PSCCH. Such PSCCH signaling may be implemented by a field of one or more SCI bits (specific or reused) or a new SCI format to indicate a new power save state to be changed;

second stage SCI via PSSCH; and

PDCCH signaling if the UE is in the gNB coverage (mode 1 or mode 2). Such signaling may be implemented through a field of DCI bits or a new DCI format.

Fig. 9 depicts a flowchart 900 illustrating configuring a UE to operate in one of a plurality of power saving states of the UE using RRC configuration from an upper layer in accordance with an embodiment of the present disclosure. In this embodiment, a new RRC parameter SwitchPowerSavingState is used, and four different values of the new RRC parameter indicate four power saving state configurations (states D1-D4), respectively. For simplicity, only the use of the new RRC parameter SwitchPowerSavingState for RRC configuration is demonstrated. It is to be appreciated that other RRC parameters may additionally or alternatively be used as an indication to implement power saving state configuration signaling.

Fig. 10 depicts a flowchart 1000 illustrating configuring a UE to operate in one of a plurality of power saving states using a PSCCH according to another embodiment of the present disclosure. In the present embodiment, PSCCHs having two SCI bits "00", "01", "10", and "11" are used to indicate four power saving state configurations (states D1, D2, D3, and D4), respectively.

Similarly, fig. 11 depicts a flow chart 1100 illustrating using PDCCH to configure a UE to operate in one of a plurality of power saving states in accordance with yet another embodiment of the present disclosure. In the present embodiment, PDCCHs having two DCI bits "00", "01", "10", and "11" are used to indicate four power saving state configurations (states D1, D2, D3, and D4), respectively.

According to the present disclosure, a UE may operate by switching from one power saving state to another power saving state by event triggering. Such a trigger event may come from the UE itself, another UE, the gNB, or the network. In one embodiment, the UE upper layer determines a preference to switch its power saving state to another power saving state, e.g., in order to reduce power consumption or to have better performance (with increased capabilities). Such preferences for operating in other power saving states may be determined based on parameters and related factors related to the UE.

If the UE is within network coverage, it informs the network of its preferred/expected power save state. If the network agrees, the network will inform the UE of the switching of the power saving state; otherwise, no handover occurs. On the other hand, if the UE is not within network coverage or the network does not control the switching of the power saving state of the UE, the UE is then configured to switch to its preferred/desired power saving state.

Fig. 12 depicts a flowchart 1200 showing a process of switching from a current power saving state to a preferred power saving state of a UE in accordance with an embodiment of the present disclosure. In step 1202, the UE is configured to determine a preferred power saving state. In step 1204, the UE determines whether it is within network (or gNB) coverage. If the UE is within network coverage, then step 1206 is performed; otherwise, step 1212 is performed. In step 1206, the UE is configured to determine whether the network controls a handover of the power saving state of the UE. If a network control handover, then step 1208 is performed; otherwise, step 1212 is performed. In one embodiment, the UE is then further configured to send a request signal to the network indicating its preferred power saving state and a request to switch to the preferred power saving state. In step 1208, the UE is configured to determine whether the network agrees to switch to the preferred power saving state of the UE, for example, by determining whether the UE receives a response signal accepting the request. If the network does not agree, then step 1210 is performed, wherein the UE does not switch to its preferred power saving state and maintains its operation in the current power saving state; otherwise, step 1212 is performed. In step 1212, the UE is then configured to operate (or switch to) its preferred power saving state.

In addition to a request signal indicating a request to switch to the preferred power saving state instead of the request signal, the UE may also transmit assistance information including parameters (with related factors) related to the UE to the network (or the gNB).

Fig. 13 depicts a flowchart 1300 illustrating a process of indicating, by another communication device, a handoff from a power save state currently operated by the communication device to another power save state, in accordance with an embodiment of the present disclosure. For simplicity, the process is demonstrated using a network. It is appreciated that any other communication device, such as a gNB and another side link UE, may be used in place of the network in instructing the UE to switch from the current power saving state to the other power saving state.

In step 1302, the UE is configured to report its parameters and related factors to the network. In one embodiment, such parameters and related factors are included in UE assistance information sent to the network. In step 1304, the network is configured to evaluate the parameters and related factors. In step 1306, the network is configured to determine whether the UE needs to switch its power save state. If it is determined by the network that a handover of the power saving state of the UE is required, e.g. when the network determines that a certain power saving state is better suited for the UE to operate under than the current power saving state in which the UE operates (with balanced power saving and performance requirements), step 1308 is performed, wherein the network is then configured to inform the UE to switch to another power saving state, e.g. by sending the UE the previously mentioned indication signal for indicating the other power saving state; otherwise, step 1310 is performed. In step 1310, for example, it is determined that the UE does not need to perform a handover, e.g., there is no more suitable power saving state than the current power saving state, the UE remains operating in the current power saving state.

In various embodiments, the UE may be configured to determine to operate in (or switch to) a particular power saving state, or a power saving state with or without certain features/functions supported. Similarly, an indication signal (e.g., RRC, PSCCH, and PDCCH signals as shown in fig. 10-12) or response signal in response to a request by a UE may include informing the UE to operate in (or switch to) a particular power save state (directly), or a power save state that supports or does not support certain features/functions.

For example, the UE may receive a signal to switch to the preferred power saving state D2, and if the UE is currently operating in the power saving state D3, it will then switch to operating in the power saving state D2. Alternatively, the UE may receive a signal to operate in a state supporting the PSSCH, and thus the UE may determine to operate in (or switch to) such a power saving state. For example, if the UE is operating in state D3, after receiving the signal, it will then switch to state D1 or D2. On the other hand, the UE may receive a signal to operate in a state where PSSCH is not supported, and thus the UE may determine to operate in (or switch to) such a power saving state. For example, if the UE is operating in state D1, after receiving the signal, it will then switch to state D3 or D4.

As previously mentioned, the SL UE may be (pre) configured with a default/initial power saving state of a plurality of power saving states operable by the SL UE. When the SL UE switches to a power save state that is not its default/initial power save state, a back-off timer (e.g., timer-based back-off parameters) may be started and used to switch back to its default/initial power save state once the back-off timer expires. Such timer-based backoff parameters may be configured using one of RRC signaling as pattern/timer or MAC/PSCCH signaling similar to Discontinuous Reception (DRX).

Fig. 14 depicts a flowchart 1400 illustrating a process of operating in a default power saving state in accordance with an embodiment of the present disclosure. In step 1402, the UE may be configured to operate in a default/initial power saving state. In step 1404, the UE may also be configured to determine another power saving state to operate under, and thus switch to, the power saving state. In step 1406, a timer is started. In step 1408, it is determined whether the timer has expired. If the timer has not expired, step 1410 is performed to decrease the timer by one unit. If the timer has expired, the UE is configured to operate in its default power saving state.

Such default power saving state may also be (pre) configured or (pre) defined by any of the specifications (e.g. 3GPP specifications), government regulatory authorities or UE suppliers. Note that the behaviour of the different power saving states should be defined in 3GPP (RRC configuration, UE capabilities, etc.). Which states are to be implemented by upper layer operations, and under what use case a certain state is to be implemented, should be in accordance with country/region regulations or UE implementations and determinations.

In embodiments of the present disclosure, for a UE that supports only PSCCH reception and its features (such as PSCCH reception for sensing only), as shown in state D3 of fig. 8, the UE need only be active when receiving the first stage SCI (e.g., the first 2 or 3 symbols in the SL slot) to monitor the PSCCH without the second stage SCI or PSCCH. In particular, a UE may be defined to have only PSCCH sensing occasions without a PSCCH receive slot/subframe. For the remaining symbols/slots of the PSCCH, the UE may be in a (micro/shallow/deep) sleep mode. Alternatively, the PSSCH reception slot/subframe can be defined as the same reception state as that supporting PSSCH reception, and the UE will monitor PSCCH symbols within the PSSCH reception slot/subframe.

Further, if another SL UE intends to send a SL message carried by the PSSCH to a SL UE having only PSCCH sensing, the other SL UE may need to send a separate PSCCH to inform the SL UE to switch to other power saving states that can be used for PSSCH reception. The separate PSCCH may carry one or more bits in the SCI to inform the state of a switch to some power saving state or support function (e.g., PSSCH reception).

In the following paragraphs, certain exemplary embodiments are explained with reference to terms related to a 5G core network and the present disclosure regarding communication devices and methods for side link broadcasting, namely:

control signal

In the present disclosure, the downlink control signal (information) related to the present disclosure may be a signal (information) transmitted through a PDCCH of a physical layer or may be a signal (information) transmitted through a MAC Control Element (CE) of a higher layer or RRC. The downlink control signal may be a predefined signal (information).

The uplink control signal (information) related to the present disclosure may be a signal (information) transmitted through a PUCCH of a physical layer or may be a signal (information) transmitted through a MAC CE of a higher layer or RRC. Furthermore, the uplink control signal may be a predefined signal (information). The uplink control signal may be replaced with Uplink Control Information (UCI), first stage side link control information (SCI), or second stage SCI.

Base station

In the present disclosure, for example, a base station may be a Transmission Reception Point (TRP), a cluster head, an access point, a Remote Radio Head (RRH), an eNodeB (eNB), a gndeb (gNB), a Base Station (BS), a Base Transceiver Station (BTS), a base station unit, or a gateway. Further, in the side link communication, a terminal may be employed instead of a base station. The base station may be a relay device that relays communication between the upper node and the terminal. The base station may also be a roadside unit.

Uplink/downlink/side link

The present disclosure may be applied to any one of uplink, downlink, and side link.

The present disclosure may be applied to uplink channels such as PUSCH, PUCCH, and PRACH; downlink channels such as PDSCH, PDCCH, and PBCH; and side link channels such as a physical side link shared channel (PSSCH), a physical side link control channel (PSCCH), and a physical side link broadcast channel (PSBCH).

PDCCH, PDSCH, PUSCH and PUCCH are examples of downlink control channels, downlink data channels, uplink data channels and uplink control channels, respectively. PSCCH and PSSCH are examples of side link control channels and side link data channels, respectively. PBCH and PSBCH are examples of broadcast channels, respectively, and PRACH is an example of a random access channel.

Data channel/control channel

The present disclosure may be applied to any one of a data channel and a control channel. 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.

Reference signal

In the present disclosure, 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 as a pilot signal. The reference signals may be DMRS, channel state information-reference signals (CSI-RS), tracking Reference Signals (TRS), phase Tracking Reference Signals (PTRS), cell specific reference signals (CRS), and Sounding Reference Signals (SRS).

Time interval

In the present disclosure, the time resource unit is not limited to one of a slot and a symbol or a combination thereof, and may be a time resource unit such as a frame, a superframe, a subframe, a slot sub-slot, a micro-slot, or a time resource unit such as a symbol, an Orthogonal Frequency Division Multiplexing (OFDM) symbol, a single carrier frequency division multiplexing access (SC-FDMA) symbol, or other time resource units. The number of symbols included in one slot is not limited to any number of symbols exemplified in the above-described embodiment, and may be other numbers of symbols.

Frequency band

The present disclosure may be applied to any one of a licensed band and an unlicensed band.

Communication system

The present disclosure can be applied to any one of communications between a base station and a terminal (Uu-link communications), communications between terminals (side link communications), and vehicle-to-everything (V2X) communications. The channels in the present disclosure may be replaced with PSCCH, PSSCH, physical side link feedback channel (PSFCH), PSBCH, PDCCH, PUCCH, PDSCH, PUSCH, and PBCH.

In addition, the present disclosure may be applied to any one of a terrestrial network using satellites or High Altitude Pseudolites (HAPS) or a network other than the terrestrial network (NTN: non-terrestrial network). In addition, the present disclosure may be applied to networks having large cell sizes and terrestrial networks having large delays compared to symbol lengths or slot lengths, such as ultra wideband transmission networks.

Antenna port

An antenna port refers to a logical antenna (antenna group) made up of one or more physical antennas. That is, the antenna port does not necessarily mean one physical antenna, and may mean an array antenna constituted by a plurality of antennas or the like. For example, how many physical antennas constitute an antenna port is not defined, but the antenna port is defined as a minimum unit allowing a terminal to transmit a reference signal. The antenna ports may also be defined as the minimum unit of precoding vector weight multiplication.

The present disclosure may be implemented in software, hardware, or a combination of software and hardware. Each of the functional blocks used in the description of the above embodiments may be partially or entirely implemented by an LSI such as an integrated circuit, and each of the processes described in the embodiments may be partially or entirely controlled by the same LSI or combination of LSIs. The LSI may be formed as a single chip or one chip may be formed as a system including some or all of the functional blocks. The LSI may include data inputs and outputs coupled thereto. Here, the LSI may be referred to as an IC, a system LSI, an ultra LSI, or a very large LSI according to the difference in integration level. However, the technique of implementing the integrated circuit is not limited to LSI, and may be implemented by using a dedicated circuit, a general-purpose processor, or a dedicated processor. In addition, an FPGA (field programmable gate array) which can be programmed after LSI manufacturing or a reconfigurable processor which can reconfigure connection and setting of circuit cells arranged inside an LSI may be used. The present disclosure may be implemented as digital processing or analog processing. If future integrated circuit technology replaces LSI due to advances in semiconductor technology or other derivative technology, the functional blocks may be integrated using future integrated circuit technology. Biotechnology may also be applied.

The present disclosure may be implemented by any kind of apparatus, device, or system having a communication function (hereinafter referred to as a communication apparatus).

The communication device may include a transceiver and processing/control circuitry. The transceiver may include and/or function as a receiver and a transmitter. The transceivers as transmitters and receivers may include an RF (radio frequency) module including an amplifier, an RF modulator/demodulator, etc., and one or more antennas.

Some non-limiting examples of such communication means include telephones (e.g., cellular (cell) phones, smart phones), tablet computers, personal Computers (PCs) (e.g., laptops, desktops, netbooks), cameras (e.g., digital still/video cameras), digital players (digital audio/video players), wearable devices (e.g., wearable cameras, smartwatches, tracking devices), gaming machines, digital book readers, telemedicine/telemedicine (telemedicine and medical) devices, and vehicles providing communication functions (e.g., automobiles, airplanes, propagation), and various combinations thereof.

The communication devices are not limited to portable or mobile, and may also include any kind of non-portable or fixed devices, equipment, or systems, such as smart home devices (e.g., appliances, lighting, smartmeters, control panels), vending machines, and any other "thing" in the network of "internet of things (IoT)".

Communication may include exchanging data through, for example, a cellular system, a wireless LAN system, a satellite system, and the like, as well as various combinations thereof.

The communication means may comprise a device such as a controller or a sensor coupled to a communication device performing the communication functions described in the present disclosure. For example, the communication apparatus may comprise a controller or sensor that generates control signals or data signals for use by a communication device performing the communication functions of the communication apparatus.

The communication devices may also include infrastructure, such as base stations, access points, and any other devices, apparatuses, or systems that communicate with or control devices, such as those in the non-limiting examples described above.

It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the 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 as illustrative and not restrictive.

Claims (16)

1. A communication apparatus, comprising:

circuitry to determine one of a plurality of power saving states to operate under; and

and a transceiver for transmitting and/or receiving at least one type of side link signal in response to determining one of the plurality of power saving states.

2. The communication device of claim 1, wherein the circuitry is configured to determine one of the plurality of power saving states to operate under based on an identification of a transmit and/or receive priority associated with the at least one type of side-chain signal.

3. The communication device of claim 1 or 2, wherein one of the plurality of power saving states relates to one of: (a) reception of all types of side link signals, (b) reception of only physical side link control channel (PSCCH) and physical side link shared channel (PSSCH), (c) reception of only PSCCH, (d) reception of side link synchronization block (S-SSB) and/or physical side link feedback channel (PSFCH), and (e) reception of only PSCCH and second stage side link control information (SCI).

4. A communications device according to claim 3, wherein when one of the plurality of power saving states involves the reception of a PSCCH only, the communications device is configured to be active on receipt of a first stage SCI.

5. The communication device of claim 1, wherein the circuitry is configured to determine one of the plurality of power saving states to operate under based on a parameter related to the communication device.

6. The communication device of claim 5, wherein the parameter comprises at least one of a speed of the communication device, a communication device type, a vehicle type, a Global Navigation Satellite System (GNSS) location, a congestion level, an area ID.

7. The communication device of claim 5 or 6, wherein the transceiver further transmits assistance information comprising the parameter to another communication device.

8. The communication device of claim 1, wherein the transceiver further transmits a request signal to another communication device indicating a request to operate in one of the plurality of power saving states.

9. The communication device of claim 8, wherein the transceiver further receives a response signal accepting the request, and the circuit is configured to determine one of the plurality of power saving states to operate under based on the response signal.

10. The communication device of claim 1, wherein the transceiver receives an indication signal from another communication device regarding one of the plurality of power saving states, and wherein the circuitry is configured to determine one of the plurality of power saving states to operate under based on the indication signal.

11. The communication device of claim 10, wherein the indication signal relates to at least one of: side link control indication (SCI) signaling, downlink Control Indication (DCI) signaling, medium Access Control (MAC) Control Element (CE) signaling, and Radio Resource Control (RRC) signaling.

12. The communications apparatus of claim 11, wherein the SCI signaling is carried by one of: a first stage SCI of an independent physical side link control channel (PSCCH), a PSCCH with a dummy physical side link shared channel (PSSCH), and a second stage SCI; and the DCI signaling is carried by a Physical Downlink Control Channel (PDCCH).

13. The communication device of claim 1, wherein the at least one type of side link signal comprises at least one of: physical side link control channel (PSCCH), physical side link shared channel (PSSCH), side Link Synchronization Signal (SLSS), physical side link broadcast channel (PSBCH), physical side link feedback channel (PSFCH).

14. The communication device of claim 1, wherein the circuit is further configured with a default power saving state and a back-off timer, the default power saving state being another one of the plurality of power saving states, the back-off timer being triggered when one of the plurality of power saving states operates and switching from one of the plurality of power saving states to the default power saving state upon expiration of the back-off timer.

15. The communications apparatus of claim 14, wherein the back-off timer is configured using one of RRC signaling, MAC signaling, and PSCCH signaling.

16. A method of communication, comprising:

operating in one of a plurality of power saving states, each of the plurality of power saving states corresponding to a side link capability; and

at least one type of side link signal is transmitted and/or received based on a side link capability corresponding to one of the plurality of power saving states.