CN115314862A

CN115314862A - Communication method and associated apparatus, system, medium, product and chip

Info

Publication number: CN115314862A
Application number: CN202110492066.7A
Authority: CN
Inventors: 李翔宇; 彭文杰
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2021-05-06
Filing date: 2021-05-06
Publication date: 2022-11-08
Also published as: WO2022233257A1

Abstract

The embodiment of the application provides a communication method and a related device, system, medium, product and chip, and relates to the field of communication. In a communication method, a first terminal device determines whether a second terminal device requires system information from a network device; and if it is determined that the second terminal device requires system information, the first terminal device transmits the system information to the second terminal device via a sidelink connection, the sidelink connection being a communication connection established between the first terminal device and the second terminal device. Therefore, the increase of equipment power consumption caused by unnecessary SI transmission can be avoided, the signaling overhead among equipment is reduced, the communication resource is saved, and the side link communication quality can be ensured.

Description

Communication method and associated apparatus, system, medium, product and chip

Technical Field

Embodiments of the present application relate generally to the field of communications, and in particular, to a communication method and an associated communication apparatus, a communication system, a computer-readable storage medium, a computer program product, and a chip.

Background

With the development of communication technology, in device-to-device (D2D) communication, a terminal-to-network (UE to NW, U2N) relay technology has been proposed. The U2N relay technology refers to a communication technology in which one terminal device (referred to as a remote relay terminal device or a remote UE) accesses a network through another terminal device (referred to as a relay terminal device or a relay UE). U2N relay technology helps to promote network coverage enhancement, for example, in cases where the network coverage signal of the remote UE is poor or out of network coverage. Furthermore, U2N relay technology can also help provide network capacity, especially if the relay UE is a very communication capable device. The remote UE and the relay UE may communicate by establishing a Sidelink (SL) connection.

Disclosure of Invention

The embodiment of the application provides a communication scheme, in particular a scheme of side link communication.

In a first aspect of the present application, a method of communication is provided. The method comprises the following steps: the first terminal equipment determines whether the second terminal equipment needs system information from the network equipment; and if it is determined that the second terminal device needs the system information, the first terminal device transmits the system information to the second terminal device via a sidelink connection, which is a communication connection established between the first terminal device and the second terminal device.

According to the embodiment of the application, whether the second terminal equipment needs or is interested in the system information is judged, so that the increase of equipment power consumption caused by unnecessary system information transmission can be avoided, the signaling overhead among equipment is reduced, the communication resource is saved, and the communication quality of the side link can be ensured.

In some embodiments of the first aspect, determining whether the second terminal device requires system information comprises: the first terminal equipment receives indication information from the second terminal equipment; and the first terminal device determines that the second terminal device needs the system information based on the indication information. In this way, it is possible for the second terminal device to determine and indicate to the first terminal device whether it needs system information or what similar system information is needed. The second terminal device can more flexibly acquire the system information which is needed or interested.

In some embodiments of the first aspect, the indication information comprises at least one of: the first indication is used for indicating that the second terminal equipment needs the system information of a plurality of types, and the second indication is used for indicating that the second terminal equipment needs at least one type of the system information of the plurality of types. Different indications may be used to flexibly indicate to the first terminal device the need or interest of the second terminal device for one or more types, or all, of similar system information.

In some embodiments of the first aspect, the method further comprises: the first terminal equipment transmits first information to the second terminal equipment, the first information is used for assisting the second terminal equipment to determine the indication information, and the first information comprises at least one of the following items: the network connection state information of the first terminal device, the cell identification information corresponding to the first terminal device, and the validity related information corresponding to at least one type of system information in the plurality of types of system information. Through information interaction between the terminal devices, the second terminal device can be assisted to more accurately and quickly determine whether the system information is needed and which type or types of system information are needed.

In some embodiments of the first aspect, determining whether the second terminal device requires system information comprises: the first terminal device receives second information from the second terminal device, the second information including at least one of: network connection state information of a second terminal device, cell identification information corresponding to the second terminal device, and validity related information corresponding to at least one type of system information in the plurality of types of system information; and the first terminal device determines whether the second terminal device needs the system information based on the second information. Through information interaction from the second terminal device, the first terminal device can be assisted to more accurately and quickly determine whether the second terminal device needs the system information and which type or types of system information are needed.

In some embodiments of the first aspect, the validity-related information comprises at least one of: valid time information for indicating validity duration or validity remaining time of the corresponding system information; region range information for corresponding system information; region identification information for corresponding system information; cell identification information corresponding to the first terminal device; public Land Mobile Network (PLMN) identification information for corresponding system information; and numerical label information for corresponding system information. The different validity-related information may be used to accurately judge the need of the second terminal device for the system information from different aspects, so that the second terminal device can be provided with the system information in the case that it needs or is interested in.

In some embodiments of the first aspect, determining whether the second terminal device requires system information based on the second information comprises: the first terminal device determines that the second terminal device requires system information based on at least one of: the network connection state information indicates that the second terminal device is in an out-of-coverage (OOC) state, and the cell identification information corresponding to the second terminal device is different from the cell identification information corresponding to the first terminal device. The connection state information and/or the cell identity may better indicate the situation where the second terminal device needs system information, e.g. determining whether the second terminal device needs minimum system information.

In some embodiments of the first aspect, determining whether the second terminal device requires system information based on the second information comprises: the first terminal device determines whether at least one type of system information currently stored at the second terminal device is valid based on the validity-related information; and if the currently stored at the second terminal equipment is determined to be invalid, the first terminal equipment determines that the second terminal equipment needs the at least one type of system information. By determining the validity of the system information, it can be ensured that the system information at the second terminal device is provided with the required and valid system information in case it is invalid.

In some embodiments of the first aspect, transmitting the system information to the second terminal device comprises: if it is determined that the second terminal device requires at least one type of system information among the plurality of types of system information and the first terminal device does not store at least one type of valid system information, the first terminal device requests the network device for at least one type of system information; the first terminal equipment receives at least one type of system information from the network equipment; and the first terminal device transmitting at least one type of system information to the second terminal device. In such an embodiment, if the second terminal device needs some or some similar system information, but the first terminal device does not store the corresponding system information, the first terminal device can also request the network device and forward the system information to the second terminal device by means of an on-demand request, so as to meet the requirement of the second terminal device.

In some embodiments of the first aspect, the method further comprises: the method comprises the steps that a first terminal device determines valid time information corresponding to system information which is transmitted to a second terminal device, wherein the valid time information is used for indicating validity duration or validity residual time of the system information; and if the validity duration of the system information reaches a first threshold or the validity remaining time reaches a second threshold, the first terminal device transmits additional system information to the second terminal device. In this manner, the first terminal device may continuously maintain the validity of one or more types of system information previously transmitted to the second terminal device, thereby being able to actively and timely update the system information for the second terminal device in case the system information is about to be or has become invalid, thereby ensuring the communication quality at the second terminal device.

In a second aspect of the present application, a method of communication is provided. The method comprises the following steps: the second terminal device executes a process of establishing a sidelink connection with the first terminal device, the sidelink connection being at least used for relaying information from the network device to the second terminal device by the first terminal device; and in the event that it is determined that the second terminal device requires system information, the second terminal device receives the system information from the first terminal device via the sidelink connection.

In some embodiments of the second aspect, receiving system information comprises: the second terminal equipment transmits the indication information to the first terminal equipment so as to indicate the first terminal equipment that the second terminal equipment needs system information; and the second terminal device receives the system information from the second terminal device based on the transmission of the indication information.

In some embodiments of the second aspect, the indication information comprises at least one of: the first indication is used for indicating that the second terminal equipment needs the system information of a plurality of types, and the second indication is used for indicating that the second terminal equipment needs at least one type of the system information of the plurality of types.

In some embodiments of the second aspect, transmitting the indication information comprises: if the second terminal device is in an out-of-coverage (OOC) state, the second terminal device determines that system information is needed; and the second terminal equipment transmits the indication information to the first terminal equipment.

In some embodiments of the second aspect, the method further comprises: the second terminal device receives first information from the first terminal device, the first information including at least one of: the method comprises the steps that network connection state information of first terminal equipment, cell identification information corresponding to the first terminal equipment and validity related information corresponding to at least one type of system information in a plurality of types of system information are obtained; the second terminal device determines that the second terminal device needs system information based on the first information; and the second terminal device generates the indication information based on the determination.

In some embodiments of the second aspect, determining that the second terminal device requires system information based on the first information comprises: the second terminal device determines that the second terminal device requires system information based on at least one of: the network connection state information of the first terminal device is different from the network connection state information of the second terminal device, and the cell identification information corresponding to the second terminal device is different from the cell identification information corresponding to the first terminal device.

In some embodiments of the second aspect, determining that the second terminal device requires system information based on the first information comprises: the second terminal device determines whether at least one type of system information currently stored at the second terminal device is valid based on the validity-related information; and if the at least one type of system information currently stored at the second terminal device is determined to be invalid, the second terminal device determines that the at least one type of system information is required by the second terminal device.

In some embodiments of the second aspect, the method further comprises: the second terminal device transmits second information to the first terminal device, the second information being used for assisting the first terminal device to determine whether the second terminal device needs system information, and the second information including at least one of the following: the network connection state information of the second terminal device, the cell identification information corresponding to the second terminal device, and the validity related information corresponding to at least one type of system information in the plurality of types of system information.

In some embodiments of the second aspect, the validity-related information comprises at least one of: valid time information indicating validity duration or validity remaining time of a specific type of system information, area range information for corresponding system information, area identification information for corresponding system information, cell identification information corresponding to the first terminal device, public Land Mobile Network (PLMN) identification information for corresponding system information, and numerical label information for corresponding system information.

In a third aspect of the present application, a communication apparatus implemented at a first terminal device is provided. The apparatus includes a determining unit configured to determine whether the second terminal device requires system information from the network device; and a first transmission unit configured to, if it is determined that the second terminal device requires system information, the first terminal device transmits the system information to the second terminal device via a sidelink connection, which is a communication connection established between the first terminal device and the second terminal device

In some embodiments of the third aspect, the apparatus comprises functional means for implementing any of the implementations of the first aspect.

In a fourth aspect of the present application, a communication apparatus implemented at a second terminal device is provided. The apparatus includes a connection establishing unit configured to perform a setup procedure of a sidelink connection with a first terminal device, the sidelink connection being at least used for relaying, by the first terminal device, information from a network device to a second terminal device; and a first receiving unit configured to receive the system information from the first terminal device via the sidelink connection by the second terminal device in a case where it is determined that the system information is required by the second terminal device.

In some embodiments of the fourth aspect, the apparatus comprises functional means for implementing any of the implementations of the second aspect.

In a fifth aspect of the present application, a communication apparatus implemented at a first terminal device is provided. The apparatus comprises at least one processing unit; may further comprise at least one memory coupled to the at least one processing unit and storing instructions for execution by the at least one processing unit, which when executed by the at least one processing unit, cause the communication apparatus to carry out operations according to the method in any one of the possible implementations of the first aspect described above.

In a sixth aspect of the present application, a communication apparatus implemented at a second terminal device is provided. The apparatus comprises at least one processing unit; may further comprise at least one memory coupled to the at least one processing unit and storing instructions for execution by the at least one processing unit, which when executed by the at least one processing unit, cause the communication apparatus to carry out operations according to the method in any one of the possible implementations of the second aspect described above.

In a seventh aspect of the present application, a communication system is provided. The communication system comprises at least one communication device according to the above third or fifth aspect. The communication system may further comprise at least one communication device according to the fourth or sixth aspect described above.

In an eighth aspect of the present application, a computer-readable storage medium is provided. The computer-readable storage medium has stored thereon a computer program which, when executed by a processor, performs the operations according to the method of any one of the possible implementations of the first and/or second aspect.

In a ninth aspect of the present application, a computer program product is provided. The computer program product is tangibly stored on a computer-readable medium and comprises computer-executable instructions that, when executed, cause an apparatus to implement operations according to a method in any one of the possible implementations of the first and/or second aspect described above.

In a tenth aspect of the present application, a chip is provided. The chip is configured to perform the operations according to the method in any one of the possible implementations of the first and/or second aspect described above.

It will be appreciated that the communication devices, systems, media, computer program products or chips provided above are all for implementing the methods provided by the first and/or second aspect. Thus, explanations or illustrations with respect to the first and/or second aspect apply equally to the communication means, medium, chip, device or computer program product provided by the above-described aspects. In addition, the beneficial effects that can be achieved by the communication device, the system, the medium, the computer program product or the chip provided in these aspects can refer to the beneficial effects in the corresponding method, and are not described herein again.

These and other aspects of the present application will be more readily apparent from the following description of the embodiment(s).

Drawings

The above and other features, advantages and aspects of various embodiments of the present application will become more apparent by referring to the following detailed description when taken in conjunction with the accompanying drawings. In the drawings, like or similar reference characters designate like or similar elements, and wherein:

fig. 1 shows a schematic block diagram of a communication system in which embodiments of the present application may be found;

FIG. 2 illustrates an interactive signaling diagram of a communication process between devices according to some embodiments of the present application;

figures 3A and 3B illustrate interactive signaling diagrams of a process of determining a terminal device's need for system information according to some embodiments of the present application;

fig. 4 illustrates a flow chart of a communication method implemented at a first terminal device according to some embodiments of the present application;

fig. 5 illustrates a flow chart of a communication method implemented at a second terminal device according to some embodiments of the present application;

fig. 6 illustrates a schematic block diagram of a communication apparatus implemented at a first terminal device in accordance with some embodiments of the present application;

figure 7 shows a schematic block diagram of a communication apparatus implemented at a second terminal device according to some embodiments of the present application; and

FIG. 8 illustrates a simplified block diagram of an example device suitable for implementing embodiments of the present application.

Detailed Description

Embodiments of the present application will be described in more detail below with reference to the accompanying drawings. While certain embodiments of the present application are shown in the drawings, it should be understood that the present application may be embodied in various forms and should not be construed as limited to the embodiments set forth herein, but rather are provided for a more thorough and complete understanding of the present application. It should be understood that the drawings and embodiments of the present application are for illustration purposes only and are not intended to limit the scope of the present application.

In describing embodiments of the present application, the terms "include" and "comprise," and similar language, are intended to be open-ended, i.e., "including but not limited to. The term "based on" should be understood as "based at least in part on". The term "one embodiment" or "the embodiment" should be understood as "at least one embodiment". The terms "first," "second," and the like may refer to different or the same object. Other explicit and implicit definitions are also possible below. In the description of embodiments of the present application, "at least one of A, B and C" and similar terms may include one or more of the following combinations: a, B, C, AB, BC, AC, ABC. Other similar expressions may be similarly understood.

Embodiments of the present application may be implemented in accordance with any suitable communication protocol, including, but not limited to, fourth generation (4G) and fifth generation (5G) cellular communication protocols, wireless local area network communication protocols such as Institute of Electrical and Electronics Engineers (IEEE) 802.11, and/or any other protocol now known or later developed. The technical solution of the embodiments of the present application is applied to comply with any suitable communication system, for example: a Long Term Evolution (LTE) system, a narrowband internet of things (NB-IoT) communication system, a fifth generation (5G) system, or a New Radio (NR), among others. Further, the communication may utilize any suitable wireless communication technology, including but not limited to: code Division Multiple Access (CDMA), frequency Division Multiple Access (FDMA), time Division Multiple Access (TDMA), frequency Division Duplex (FDD), time Division Duplex (TDD), multiple Input Multiple Output (MIMO), orthogonal Frequency Division Multiplexing (OFDM), discrete Fourier transform spread spectrum OFDM (DFT-s-OFDM), and/or any other technique now known or later developed.

For purposes of illustration, some embodiments of the present application are described below in the context of a third generation partnership project (3 GPP) communication system of 5G. However, it should be understood that the embodiments of the present application are not limited to being applied to a 3GPP communication system of 5G, but may be applied to any communication system having similar problems, such as a Wireless Local Area Network (WLAN), a wired communication system, or other communication systems developed in the future, and the like.

The term "terminal device" as used in this application refers to any terminal device capable of wired or wireless communication with network devices or with each other. A terminal device, which may also sometimes be referred to as a User Equipment (UE), a Mobile Station (MS), a Mobile Terminal (MT), etc., is capable of providing voice and/or data connectivity to a user. The terminal device may be any type of mobile terminal, fixed terminal or portable terminal. As an example, a terminal device may include a mobile handset, a station, a unit, a device, a Subscription Station (SS), a Portable Subscription Station (PSS), an internet node, a communicator, a desktop computer, a laptop computer, a notebook computer, a tablet computer, a Personal Communication System (PCS) device, a personal navigation device, a Personal Digital Assistant (PDA), a positioning device, a radio broadcast receiver, an electronic book device, a gaming device, an aircraft, a Virtual Reality (VR) device, an Augmented Reality (AR) device, a wearable device, an internet of things (IoT) device such as a Road Side Unit (RSU), a vehicle mounted terminal device, a terminal capable of vehicle networking (V2X) communication, a terminal device in a 5G network, or any terminal device in a future-evolution Public Land Mobile Network (PLMN), other devices available for communication, or any combination of the above. The embodiments of the present application do not limit this.

The term "network device" as used in this application is a device that may be used to communicate with a terminal device to access the terminal to a wireless network. The network device may be, for example, a device, entity or node in a Radio Access Network (RAN), sometimes also referred to as an access network device. The network devices may include various types of base stations. By way of example, the network devices may include various forms of macro base stations, micro base stations, pico base stations, femto base stations, relay stations, access points, remote Radio Units (RRUs), radio Heads (RH), remote Radio Heads (RRHs), and so forth. In systems employing different radio access technologies, the names of the network devices may differ, for example, referred to as evolved node bs (enbs or enodebs) in LTE networks, node bs (nodebs) in 3G networks, G-node bs (gnbs) or NR-node bs (NR NBs) in 5G networks, and so on. The embodiments of the present application do not limit this.

Example Environment

Fig. 1 shows a schematic block diagram of a communication system 100 in which embodiments of the present application may be found. As shown in FIG. 1, communication system 100 involves a plurality of terminal devices 110-1, 110-2, 120-1, 120-2 and a network device 130. For purposes of the following discussion, terminal devices 110-1, 110-2 may be referred to generally or individually as terminal device 110 (also sometimes referred to herein as a "first terminal device"), and terminal devices 120-1, 120-2 may be referred to generally or individually as terminal device 120 (also sometimes referred to herein as a "second terminal device"). The network device 130 has a certain coverage area, referred to as a cell 102. Terminal devices 120-1 and 120-2 within cell 102 of network device 130 may establish a communication connection with network device 130. Network device 130-1 is also located within the coverage area of network device 130, but may be at the edge of cell 102.

In some cases, for the purposes of coverage enhancement and/or capacity improvement, one terminal device may access the network through another terminal device, so as to receive and transmit information with the network device. The further terminal device may act as a relay role to relay information between the connected terminal device and the network device. In the example shown in fig. 1, terminal device 120-1 may implement information transceiving with network device 130 through terminal device 110-1, and terminal device 120-2 may implement information transceiving with network device 130 through terminal device 110-2. A terminal device accessing the network via another terminal device may be located outside the coverage of network device 130 (e.g., terminal device 120-1) or may be located within the coverage of network device 130 (e.g., terminal device 120-2).

In embodiments herein, for purposes of discussion, terminal device 110 is assumed to be a terminal device, also referred to as a relay terminal device or relay UE, via which network device 130 may be accessed, these terms being used interchangeably. In the embodiments herein, for purposes of discussion, terminal device 120 is assumed to be a terminal device that accesses network device 130 through terminal device 110, also referred to as a remote terminal device or remote UE, and these terms are used interchangeably. The communication connection established between terminal device 110 and terminal device 120 may be referred to as a sidelink connection. The communication between terminal device 110 and terminal device 120 may be referred to as sidelink communication or D2D communication. In some embodiments, the communication between terminal device 110 and terminal device 120 may include layer 2 (L2) UE-to-NW relay communication, or layer 3 (L3) UE-to-NW relay communication.

It should be understood that the number of devices shown in fig. 1 is for illustrative purposes only and does not imply any limitation. Any suitable number of terminal devices and/or network devices suitable for implementing embodiments of the present application may be included in environment 100. Although not shown, it is to be understood that one or more additional devices may be located in the cell 102 and served by the network device 130, and that one terminal device may not establish a sidelink connection with another terminal device, or may establish a sidelink connection with one or more additional terminal devices.

Terminal devices

110 and 120 may be in a variety of different network connection states. In some embodiments, terminal device 110 may be in an RRC CONNECTED state (RRC _ CONNECTED), an RRC IDLE state (RRC _ IDLE), an RRC INACTIVE state (RRC _ INACTIVE), or the like with network device 130, depending on the communication connection with network device 130, e.g., radio Resource Control (RRC) state. Terminal device 120 can also be in an RRC idle state, an RRC inactive state, or an RRC connected state, but the RRC state of terminal device 120 can be an RRC state with network device 130 or other network devices (not shown). In some embodiments,

terminal devices

110 and 120 may be in an In Coverage (IC) state or an out of coverage (OOC) state, taking into account relative positioning with the coverage of network device 130 and/or other network devices. The IC status of the terminal device 110 may specifically indicate that the terminal device 110 is within the coverage of the network device 130, or the OOC status may specifically indicate that the terminal device 110 is outside the coverage of other network devices. The terminal device 120 may be in an IC state or an OOC state. For example, in FIG. 1, terminal device 120-1 is in an OOC state with respect to network device 130, while terminal device 120-2 may be in an IC state with respect to network device 130. In some examples, the terminal device 120 may be in an OOC state, and the OOC state may indicate that the terminal device 120 is not within the coverage of any network device, not within the coverage of a network device supporting sidelink communications, or specifically not within the coverage of the network device 130.

To establish a sidelink connection, terminal device 110 and terminal device 120 may need to perform a discovery procedure to discover each other. In some embodiments, the discovery process may cause terminal device 110 and terminal device 120 to obtain a target layer 2 (L2) address, a target layer 1 (L1) address, etc. of the other party.

The discovery process can be performed in a variety of ways. In some embodiments, end device 120 may broadcast an announcement (announcement) message, such as a PC5-S message, to the surroundings. One or more terminal devices 110 may listen for such announcement messages. If one of the end devices 110 receives such an announcement message, the presence of the end device 120 can be known. In some embodiments, end device 110 may broadcast a request (solicitation) message to the surroundings to find end devices 120 that need to be relayed. After receiving the request message, terminal device 120 may reply a response message to terminal device 110 if the conditions allow, so that terminal device 110 knows the existence of terminal device 120. In some examples, the request message and the response message may both be PC5 interface signaling (PC 5-S) messages.

After the discovery process, in some embodiments, the

end devices

110 and 120 that are discovering each other may establish a sidelink connection for sidelink communications. The sidelink communications may support one or more of unicast communications, multicast communications, and broadcast communications. In some embodiments,

terminal devices

110 and 120 may perform an establishment procedure to establish a sidelink connection between the devices. In some embodiments, the establishment of the sidelink connection may be initiated by either of

terminal devices

110 and 120.

For example, for unicast communication, the establishment procedure of the sidelink connection may include four message steps, that is, a terminal device (referred to as terminal device 1 herein) of

terminal devices

110 and 120 sends a direct communication request (direct communication request) message to another terminal device (referred to as terminal device 2 herein). In response to the direct communication request message, the terminal device 2 sends back a direct security mode command (direct security mode command) message. After receiving the direct connection security mode command message, the terminal device 1 sends a direct security mode complete message to the terminal device 2. The terminal device 2 continues to send a direct communication accept (direct communication accept) message to the terminal device 1, thereby realizing the establishment of the side link connection.

After the side-link connection between terminal device 110 and terminal device 120 is established, terminal device 110 may relay data and/or other information from network device 130 to terminal device 120 via side-link communication, and may also relay data and/or other information from terminal device 120 to network device 130. In some embodiments, communication over sidelink connections requires that the terminal device performing the transmission obtain a resource grant in advance.

In some embodiments, resources for communication may be scheduled by network device 130, similar to the manner in which resources are scheduled on the Uu interface. For example, when the terminal device 110 needs to transmit data via the sidelink connection, it may first transmit a Buffer Status Report (BSR) corresponding to the sidelink connection to the network device 130 to report the amount of data to be transmitted. Network device 130 may assign a sidelink grant of a corresponding size to terminal device 110 for sidelink transmission. In other examples, network device 130 may configure terminal device 110 with periodic sidelink grants for periodic traffic, terminal device reporting attributes of periodic traffic (start time, period, packet size, etc.). In this way, the terminal device 110 may not need to acquire the sidelink grant by frequently reporting the BSR.

In addition to resource scheduling performed by the network device, in some embodiments, resources for sidelink communications may be acquired in an autonomous contention manner by the terminal device. For example, the

terminal device

110 or 120 may select an empty unoccupied resource for transmission by measuring whether each time-frequency resource on the sidelink connection is occupied.

It should be appreciated that only some examples of device discovery procedures, sidelink establishment procedures, and resource allocation approaches have been given above. In other examples, there may be other currently available or future developed device discovery processes, sidelink establishment processes, and resource allocation approaches. Embodiments of the present application are not limited in this respect.

Basic working principle and example signalling interaction

In the sidelink communication of the terminal device, the relay terminal device may transmit System Information (SI) from the network device to the remote terminal device. The SI contains various types of parameters of the network device and is important for the remote terminal device. However, currently there is no specific provision for how SI is relayed by a relay network device to a remote network device. In a simple scheme, it may be specified that the relay terminal device always forwards the SI to the remote terminal device after receiving the SI from the network device, for example, the forwarding may be performed by broadcasting, multicasting, dedicated PC5-RRC signaling, or the like. However, in some cases, a remote terminal device, e.g. in IC state, may have received SI from a network device, e.g. over the Uu interface. Since the relay terminal device cannot know SI reception of the remote terminal device, SI forwarded by the relay terminal device may become redundant. This may lead to unnecessary information transmission, resulting in increased power consumption of the terminal device, increased signaling overhead and wasted resources, especially in case of unicast communication. This in turn also reduces the quality of communication over the sidelink connection.

According to an embodiment of the present application, a scheme for improved sidelink communication is proposed. In this scheme, the first terminal device (i.e., the relay terminal device) may transmit the SI to the second terminal device (i.e., the remote terminal device) under certain conditions. Specifically, the first terminal device may determine whether the second terminal device requires SI from the network device. The first terminal device may perform such a determination in a number of ways. And under the condition that the second terminal equipment needs the SI, the first terminal equipment transmits the SI to the second terminal equipment. In an actual communication scenario, certain types of SI may be transmitted periodically by the network device, certain types of SI may be updated at irregular times, and the remote terminal device may have received the SI itself. By judging that the remote terminal equipment needs the SI and then transmits the SI through the side link connection, the increase of equipment power consumption caused by unnecessary SI transmission can be avoided, the signaling overhead among the equipment is reduced, the communication resource is saved, and the side link communication quality can be ensured.

Example embodiments of the present application will be discussed in detail below with reference to the accompanying drawings.

Fig. 2 illustrates an interactive signaling diagram of a communication process 200 according to some embodiments of the present application. For ease of discussion, process 200 will be discussed with reference to communication system 100 of fig. 1. Process 200 involves terminal device 110, terminal device 120, and network device 130 of fig. 1. The

terminal devices

110 and 120 referred to herein may be any of the

terminal devices

110 and 120 shown in fig. 1.

As shown in fig. 2, to perform sidelink communications, terminal device 110 and terminal device 120 may perform (205) a sidelink connection establishment procedure. The setup procedure may be performed, for example, according to any of the manners mentioned above or other suitable manners. After the sidelink connection is established, terminal device 110 may relay or forward data, information, etc. from network device 130 to terminal device 120 via the sidelink connection. For example, terminal device 110 may relay SI to terminal device 120.

In some embodiments, the end device 110 may be located within the coverage of the network device 130 and thus be in the IC state. In some embodiments, terminal device 110 may be in an RRC CONNECTED state (RRC _ CONNECTED), an RRC IDLE state (RRC _ IDLE), or an RRC INACTIVE state (RRC _ INACTIVE) with network device 130, among others. In some embodiments, the end device 120 may be located within the coverage of the network device 130 and thus in an IC state, or may be located out of coverage and thus in an OOC state. In some embodiments, terminal device 120 may be in an RRC idle state, an RRC inactive state, or an RRC connected state with network device 130. In some embodiments, the relay communication between terminal device 110 and terminal device 120 may include layer 2 (L2) UE-to-NW relay communication, or layer 3 (L3) UE-to-NW relay communication.

In a communication network, the SI transmitted by the network device 130 may include various types of parameters needed to communicate within its coverage area. There may be multiple types of SI. In some embodiments, the SI may be classified by a System Information Block (SIB). Different types of SI may include a Master Information Block (MIB) and one or more SIBs, such as SIB1 to SIBx (where x is an integer greater than 1). The MIB may include parameters required to acquire SIB1 from the network device 130. SIB1 may include scheduling information for other SIBs (e.g., SIB to SI message mapping, periodicity, SI window size, etc.), indications related to other SIBs (e.g., indicating whether one or more other SIBs are provided by an on-demand request manner). In some embodiments, SIB1 is a cell specific (cell specific) SIB. MIB and SIB1 are sometimes referred to as Minimum SI (Minimum SI), and SIB1 may also be generally referred to as Remaining Minimum System Information (RMSI). The remaining SIBs other than the minimum SI are referred to as other SIs (other SI).

In some embodiments, the minimum SI is broadcast periodically by the network device. In some embodiments, the terminal device may receive SIB1 from the network device based on parameters in the MIB after receiving the MIB. In some embodiments, if other SIBs are provided by an on-demand request, the terminal device may send a system information request to the network device to request the other SIBs as needed. In some embodiments, other SIBs besides SIB1 may be carried in the SI message, and SIBs with the same periodicity may be mapped to the same SI message.

In some embodiments, one or more other SIBs besides SIB1 may be cell-specific or area specific (area specific). A specific granularity (cell or region) may be indicated in SIB1. Cell-specific SIBs may only be applicable to the cell range in which the SIB is provided. A SIB specific to a certain area may be associated with and usable in an area, which may include one or more cells and is identified by area identification information (identified as systemlnformationareaid) corresponding to the SIB.

In an embodiment of the present application, as a relay terminal device for terminal device 120, terminal device 110 determines (210) whether terminal device 110 requires SI from network device 130. In other words, terminal device 110 determines whether terminal device 120 is interested in SI. In some embodiments, terminal device 110 may determine whether terminal device 120 requires SI after a device discovery procedure, a connection establishment procedure, and/or initial establishment of a sidelink connection with terminal device 120. In some embodiments, terminal device 110 may periodically determine whether terminal device 120 requires SI, or perform such a determination based on an event trigger. For example, terminal device 110 receives a periodically transmitted or updated SI from network device 130, which may again determine whether such SI is to be forwarded to terminal device 120.

In some embodiments, terminal device 110 may determine whether terminal device 120 needs a corresponding SI for all of the multiple types of SIs that terminal device 120 may be to receive or for one or more specific types of SIs therein. For example, terminal device 110 may determine whether terminal device 120 requires one or more of MIB, SIB1, and other SIBs. Whether or not terminal device 120 is likely to use other SIBs may depend on the communication service of terminal device 120.

Terminal device 110 may determine whether terminal device 120 requires SI in a number of ways. In some embodiments, terminal device 110 may receive explicit or implicit indication information from terminal device 120 to determine whether SI is needed or not needed by terminal device 120. In some embodiments, terminal device 110 may determine whether terminal device 120 needs SI based on information related to the SI. Specific examples of whether the SI is needed or of interest to the terminal device 120 will be discussed in more detail below in conjunction with fig. 3A and 3B.

If terminal device 110 determines that terminal device 120 requires SI, terminal device 110 transmits (215) the SI to terminal device 120 via a sidelink connection with terminal device 120. In some embodiments, if it is determined that terminal device 120 requires all SIs or requires some type or types of SIs, terminal device 110 may send the required corresponding SIs to terminal device 120. Thereby, the terminal device 120 is able to receive (220) the required SI from the terminal device 110 via the sidelink connection, if it requires the SI.

In some embodiments, terminal device 110 may already have the SI needed by terminal device 120 stored. For example, as shown in fig. 2, network device 130 transmits (225) the SI and terminal device 110 receives (230) the SI before terminal device 110 determines that terminal device 120 needs the SI. In some embodiments, if terminal device 110 determines that terminal device 120 requires one or more types of SI, but terminal device 110 does not store the SI or SI types (or the stored SI has become invalid), then terminal device 110 may request the SI from network device 130 for terminal device 120. As shown in fig. 2, terminal device 110 optionally transmits (235) a message to network device 130 requesting one or more types of SI. Upon receiving (240) the request to terminal device 110, network device 1130 transmits (245) the requested one or more types of SI to terminal device 110. After receiving (250) these SIs by terminal device 110, it may continue to forward to terminal device 120.

In some embodiments, messages that may be used to carry SI transmitted from terminal device 110 to terminal device 120 may include, but are not limited to: a notification message sent by terminal device 110 in the device discovery process, a response message corresponding to the request message sent by terminal device 120; a direct connection security mode command message, a direct connection communication acceptance message, a direct connection communication request message, or a direct connection security mode completion message, which is sent by the terminal device 110 in the connection establishment process; PC5-S messages, PC5-RRC messages after sidelink connection establishment, etc. It should be understood that only a few examples are given here, and that other messages communicated from terminal device 110 to terminal device 120 may also be used to carry SI, or that one or more dedicated messages may be designed to transport SI or a particular type of SI. Embodiments of the present application are not limited in this respect.

Embodiments of the present application enable a relay terminal device (e.g., terminal device 110) to send SI to a remote terminal device (e.g., terminal device 120) only when the SI is needed or of interest to the remote terminal device. This can effectively avoid unnecessary SI transmission on unnecessary sidelink connections, reduce device power consumption, signaling overhead and resource waste, and improve communication quality between devices.

In some embodiments, if terminal device 110 determines that terminal device 120 does not require SI or one or more types of SI from the network device, terminal device 110 may not transmit such SI to terminal device 120 even if terminal device 110 receives updates to these types of SI from network device 130.

The procedure of how terminal device 110 determines the need for SI for terminal device 120 will be discussed in detail below with continued reference to fig. 3A and 3B.

Some example embodiments of determining a need for SI

Fig. 3A illustrates an interactive signaling diagram of a process 300 for determining the need for SI by a terminal device 120, according to some embodiments. In the embodiment of fig. 3A, terminal device 110 is indicated by terminal device 120 whether it needs SI. As shown in fig. 3A, terminal device 120 determines (315) whether it needs SI itself.

In some embodiments, the terminal device 120 may determine whether the corresponding SI is needed for all of the multiple types of SI that may be to be received or for one or more specific types of SI therein. For example, terminal device 120 may determine whether one or more of MIB, SIB1, and other SIBs are needed.

The terminal device 120 may determine which type or types of SI are of interest based on its own communication service needs, or based on whether SI has been received directly from the network device 130.

In some cases, the terminal device 120 may receive the SI from the network device 130 if the terminal device 120 is in the IC state of the network device 130. For example, terminal device 120 may be in any RRC connected state with network device 130 within the coverage of network device 130, such as an RRC idle state, an RRC inactive state, or an RRC connected state. In these RRC states, terminal device 120 may receive SI (e.g., MIB and/or SIB 1) broadcast by network device 130. Alternatively or additionally, terminal device 120 may also request other SIBs (e.g., SIB2, SIB3, etc.) from network device 130. For example, if terminal device 120 is in an RRC connected state, it may also request SI from network device 130 via an RRC message. In this case, terminal device 110 may not be aware of the requests and received information from terminal device 120 because terminal device 110 cannot parse the content of these messages.

Thus, in some embodiments, if the terminal device 120 has received all of the required SIs or one or more types of SIs, the terminal device 120 may determine that these SIs are not required. In some embodiments, terminal device 120 may also determine whether SI is needed based on the network connection status. Specifically, if the terminal device 120 is in an OOC state (e.g., terminal device 120-1 in fig. 1), the terminal device 120 may determine that an SI, particularly multiple types of SIs, is needed, and thus the terminal device 120 cannot receive messages from the network device 130 at this time. In some examples, the OOC status of the terminal device 120 may indicate that the terminal device 120 is not within the coverage of any network device, is not within the coverage of a network device supporting sidelink communications, or specifically is not within the coverage of the network device 130. In these cases, terminal device 120 may all need to have the SI of network device 130 forwarded by terminal device 110.

In some embodiments, terminal device 120 may also obtain relevant information from terminal device 110 to assist in determining whether SI is needed, or which type or types of SI are needed. As shown in fig. 3A, terminal device 110 transmits (305) the first information, and terminal device 120 receives (310) the first information from terminal device 110. The first information is used to assist the terminal device 120 in determining whether it is SI or which type or types of SI are required.

In some embodiments, the first information may include network connection status information of terminal device 110, which indicates a network connection status of terminal device 110. In some embodiments, the network connection status information may indicate that the terminal device 110 is in an IC state or an OOC state. In some examples, the IC status may specifically indicate that the terminal device 110 is within the coverage of the network device 130, or the OOC status may specifically indicate that the terminal device 110 is outside the coverage of other network devices. In some embodiments, the network connection state information may indicate which RRC state terminal device 110 is in, such as an RRC connected state, an RRC idle state, or an RRC inactive state. In some examples, a certain RRC state may specifically indicate the RRC pose of terminal device 110 with network device 130.

In some embodiments, based on the network connection status information, terminal device 120 may determine whether the network connection status of terminal device 110 is different from the network connection status of terminal device 120 and network device 130. Terminal device 120 may be in various network connection states. For example, terminal device 120 may be in an IC state but the IC state indication is the coverage of other network devices besides network device 130. Alternatively, the terminal device 120 may be in an OOC state, which may indicate that the terminal device 120 is not in the coverage of any network device, not in the coverage of a network device supporting sidelink communications, or specifically not in the coverage of the network device 130. In this case, terminal device 120 may determine that its network connection state is different from that of terminal device 110. In other embodiments, terminal device 120 may be in an RRC state, such as an RRC connected state, an RRC idle state, or an RRC inactive state. The RRC state may indicate the RRC posture of terminal device 120 with other network devices. Alternatively, the terminal device 120 is in the RRC state with the network device 130, but is in the RRC idle state, the RRC inactive state, or the like. In some embodiments, terminal device 120 may determine that the SI of network device 130 is needed if the network connection states are different. For example, in a case where the connection states are different, the terminal device 110 may be able to provide more SI that the terminal device 120 cannot obtain but needs to the terminal device 120.

Alternatively or additionally, the first information may also include cell identification information (e.g., cell ID) corresponding to terminal device 110. In some embodiments, terminal device 120 may also determine whether its corresponding cell identification information is different from the cell identification information corresponding to terminal device 110 based on the cell identification information. Terminal device 110 is typically located within cell 102 of network device 130, and thus its cell identification information may identify cell 102. If terminal device 120 roams into the vicinity of cell 102 but is not connected to or camped on network device 130, the recorded cell identification information may be the cell to which it previously connected or camped on. In this case, terminal device 120 may determine that the SI of network device 130 needs to be forwarded by network terminal device 110.

In some cases, based on network connection state information and/or cell identification information, terminal device 120 may determine whether a minimum SI, e.g., MIB and/or SIB1, is needed. For example, terminal device 120 may determine that one or both of MIB and SIB1 are required if the network connection status information indicates that the network connection status of terminal device 120 and terminal device 110 are different, and/or if the cell identification information indicates that the cell identifications of terminal device 120 and terminal device 110 correspond are different. In some embodiments, based on the network connection status information and/or cell identification information, terminal device 120 may determine that multiple types of SI are required including MIB, SIB1, and other SIBs.

In addition or as an alternative to the network connection status information and the cell identification information, the first information may also include validity related information corresponding to one or more types of SI. The validity-related information may be used to determine whether one or more types of SI that the terminal device 120 has stored are still valid. In some embodiments, the terminal device 120 may determine whether at least one type of SI currently stored at the terminal device 120 is valid based on the validity-related information. If it is determined that a certain type of SI currently stored at terminal device 120 is invalid, terminal device 120 determines that the type of SI is needed in order to be used by terminal device 110 to obtain a valid SI. The validity-related information may be specific to one type of SI. Alternatively, it is possible that the validity-related information may be the same for two or more types of SI.

In some embodiments, the validity-related information may include validity time information. One or more types of SI have a certain length of validity time. In some examples, one or more other SIBs other than the minimum SI may have corresponding effective time lengths. In some examples, one type of SI may have a corresponding length of validity time, or multiple types of SI may have the same length of validity time. The validity time length refers to the duration after obtaining the type of SI from the terminal device.

Terminal device

110 or 120 may store one type of SIB upon receiving the SIB. The SIB may be considered invalid if it is stored for more than a threshold length of time. As an example, the effective time length of the SIB may be, for example, at most 3 hours. If the SIB is stored for more than 3 hours, the SIB may be considered invalid.

For one or more types of SI, the validity time information provided by terminal device 110 to terminal device 120 may be used by terminal device 110 to obtain validity time information of the latest SI of the corresponding type. In some embodiments, the validity time information may be represented in a variety of ways. For example, the validity time information may indicate a validity duration of the corresponding type of SI, which refers to a duration from a time when the SI is received, i.e., how long it is confirmed that the corresponding type of SI has been valid. For another example, the validity time information may indicate a validity remaining time of the corresponding type of SI, i.e., a time from a current time to a time when the SI is valid for a full threshold. For example, if the length of time that an SIB is valid is 3 hours, the validity remaining time may indicate how much time remains for the SIB from being valid for 3 hours.

The terminal device 120 may determine the validity of the corresponding type of SI based on the validity time information. For example, if the validity duration of one type of SI reaches a first threshold (e.g., greater than or equal to 3 hours), then terminal device 120 may determine that the type of SI is invalid. The terminal device 120 may determine that a type of SI is invalid if the remaining time of validity of the type of SI reaches a second threshold (e.g., less than or equal to 0 hours). In some embodiments, if the validity time information of multiple types of SI (e.g., multiple other SIBs) is the same, terminal device 120 may simultaneously determine that none of these multiple types of SI are valid.

In some embodiments, the validity-related information may additionally or alternatively include other parameters for determining the validity of one or more types of SI. These parameters may be specific to one type of SI or to multiple types of SI, specific to one or more other SIBs. In some embodiments, the parameters for determining the validity of one or more types of SI include one or more of: 1) Region range information (denoted as area scope) of the corresponding type of SI, which indicates whether the corresponding type of SI is specific to a certain region, and if the region range information does not exist, may indicate that the corresponding type of SI is cell-specific; 2) Area identification information (denoted as systemlnformationareaid) of the corresponding type of SI for identifying an area to which the corresponding type of SI is specific, the area identification information may be unique under one Public Land Mobile Network (PLMN); 3) Cell identification information of the corresponding type of SI, for indicating a corresponding cell ID; 4) PLMN identification information of the corresponding type of SI may be, for example, a first PLMN ID in a PLMN ID list included in SIB 1; 5) The value tag information (denoted as value) of the corresponding type of SI may be a range of integer values, for example, values from 0 to 31, and different values may indicate different versions of the corresponding SI.

In some embodiments, the above-mentioned parameters that terminal device 110 sends to terminal device 120 may be parameters corresponding to the SI that terminal device 110 newly acquires from network device 130. Terminal device 120 may compare the above parameters received from terminal device 110 with the parameters of its stored SI of the corresponding type to determine whether its stored SI is still valid. In some embodiments, for a certain type or types of SI (e.g., one or more SIBs) that have been obtained, if the SI indicates that there is area scope information (area scope), and the PLMN identification information (first PLMN ID), area identification information (systemlnformationareaid), and numerical tag information (e.g., value) of the SI stored by the terminal device 120 are the same as the PLMN identification information (first PLMN ID), area identification information (systemlnformationaid), and numerical tag information (e.g., value) received from the terminal device 110, the terminal device 120 determines that the corresponding type of SI is still valid. Otherwise, if the terminal device 120 does not receive the area scope information (area scope) from the terminal device 110, or some of the foregoing parameters are different, the terminal device 120 determines that the SI of the corresponding type is invalid.

In some embodiments, for a certain type or types of SI (e.g., one or more SIBs) that has been obtained, if the SI indicates that there is no area scope information (area scope) and the terminal device 120 has not received the area scope information (area scope) from the terminal device 110, and the PLMN identification information (first PLMN ID), the area identification information (systemlnformationareaid), the cell ID, and the numerical tag information (e.g., value) of the SI stored by the terminal device 120 are the same as the PLMN identification information (first PLMN ID), the area identification information (systemlnformationareaid), the cell ID, and the numerical tag information (e.g., value) received from the terminal device 110, the terminal device 120 determines that the corresponding type of SI is still valid. If the terminal device 120 receives the area scope information (area scope) from the terminal device 110, or if some of the foregoing parameters are different, the terminal device 120 determines that the SI of the corresponding type is invalid.

In some embodiments, if the aforementioned parameters for multiple types of SI (e.g., multiple other SIBs) are the same, terminal device 120 may simultaneously determine that these multiple types of SI are all valid or all invalid.

The above embodiments give some example validity related information for determining the validity of an SI. In other embodiments, the validity-related information may also include other information used in communication system 100 to determine whether one or more types of SI are valid. Embodiments of the present application are not limited in this respect. In some embodiments, the terminal device 110 may provide one or more of the above-mentioned validity-related information for assisting the terminal device 120 in determining the validity of the corresponding type of SI. In some embodiments, terminal device 120 may not need validity time information from terminal device 110, but may maintain validity time information corresponding to one or more types of SI that have been previously obtained and stored by itself, and determine whether at least one type of SI currently stored is valid based on the maintained validity time information.

In some embodiments, the first information may be carried in various messages sent from terminal device 110 to terminal device 120. Examples of such messages include, but are not limited to: a notification message sent by terminal device 110 in the device discovery process, a response message corresponding to the request message sent by terminal device 120; a direct connection security mode command message, a direct connection communication acceptance message, a direct connection communication request message, or a direct connection security mode completion message, which is sent by the terminal device 110 in the connection establishment process; PC5-S messages, PC5-RRC messages after sidelink connection establishment, etc. It should be understood that only a few examples are given here, and that other messages communicated from terminal device 110 to terminal device 120 may also be used to carry the first information, or that one or more dedicated messages may be designed to transmit the first information or a specific type of first information. Embodiments of the present application are not limited in this respect. In some embodiments, the first information is sent from terminal device 110, which may be a V2X layer indicating to an Access (AS) layer to send the first information. In some embodiments, the V2X layer may be a PC5-S layer or a layer above the AS layer.

Some example embodiments of the first information are discussed below. In other embodiments, terminal device 110 may also provide other information to terminal device 120 for assisting terminal device 120 in determining whether it needs an SI, or which type or types of SIs it needs. The embodiments of the present application do not limit this.

With continued reference to fig. 3A, based on the determination of whether SI (or one or more types of SI) is needed, terminal device 120 generates corresponding indication information and transmits (320) the indication information to terminal device 110. The indication information may be used to indicate to terminal device 110 whether terminal device 120 needs the SI. Upon receiving (325) the indication from terminal device 120, terminal device 110 may determine (330) whether or not terminal device 110 needs the SI, or which type or types of SI are needed.

In some embodiments, terminal device 120 may send the indication information to terminal device 110 only if it is determined that SI is needed. In some embodiments, terminal device 110 may determine that terminal device 120 does not require SI or does not require some type of SI if the corresponding indication information is not received from terminal device 120. In some embodiments, the indication information may indicate or implicitly determine that SI is required or not required by terminal device 120, or that some type of SI is required or not.

In some embodiments, the indication information may include a first indication indicating that the terminal device 120 requires multiple types of SI for its communication. The first indication may be, for example, a general indication, without indicating the type of a specific SI. Terminal device 110 may determine, based on the first indication, that terminal device 120 requires one or more of all types of SI, MIB, SIB1, and other SIBs needed for its communication.

In some embodiments, the indication information may include a second indication indicating that the terminal device 120 requires at least one type of SI. A second example may be SI specific to one or more types, for example. Different second indications may be configured for different types or different groups of types of SI. For example, there may be indication a and indication B, where indication a is used to indicate that terminal device 120 requires the minimum SI, i.e. MIB and SIB1, and indication B is used to indicate that terminal device 120 requires other SIs. Optionally, indications B1, B2, and the like may also be included, which are respectively used to indicate different SIB combinations in other SIs, for example, indication B1 is used to indicate that terminal device 120 needs SIB2 and SIB3, indication B2 is used to indicate that terminal device 120 needs SIB2, SIB3, and SIB4, indication B3 is used to indicate that terminal device 120 needs SIB4 and SIB5, indication B4 is used to indicate that terminal device 120 needs SIB12, and the like. In some embodiments, depending on which types of SI are determined by the terminal device 120 to be needed, a corresponding indication may be included in the indication information. For example, if terminal device 120 determines that MIB, SIB1 and one or more other SIs are required, indication a and indication B may be included in the indication information.

It should be understood that only examples of indications for indicating different types of SIBs are listed here, and that any other indication is also possible. Indications specific to different types or combinations of different types may be designed to be the same value, but may be distinguished in other ways, e.g. different locations in the indication information, etc. Embodiments of the present application are not limited in this respect.

In some embodiments, the indication information may include a long-term indication. Upon receiving such indication information, terminal device 110 may determine that terminal device 120 needs the corresponding SI for a long period of time, and may thus transmit the corresponding SI to terminal device 120 multiple times. In some embodiments, the indication information may include a short-term indication. Terminal device 110 may provide the corresponding SI once to terminal device 120 upon receiving the correspondence indication information.

In some embodiments, the indication information may be carried in various messages sent from terminal device 120 to terminal device 110. Examples of such messages include, but are not limited to: the request message sent in the device discovery process, the direct connection communication request message, the direct connection safety mode completion message, the direct connection safety mode command message or the direct connection communication acceptance message sent in the side link connection establishment process, and the PC5-S message, the PC5-RRC message and the like sent after the side link connection is established. It should be understood that only a few examples are given here, and that other messages communicated from terminal device 120 to terminal device 110 may also be used to carry the indication information, or that one or more dedicated messages may be designed to transmit the indication information or a particular type of indication information. Embodiments of the present application are not limited in this respect.

Additional example embodiments for determining the need for SI

Some embodiments are discussed above in which terminal device 120 indicates to terminal device 110 whether it needs SI. Fig. 3B illustrates an interactive signaling diagram of a process 302 for determining a need for SI by a terminal device 120, according to further embodiments. In the embodiment of fig. 3B, terminal device 110 determines whether terminal device 120 needs the SI based on certain information.

As shown in fig. 3B, terminal device 120 transmits (360) second information to terminal device 110 to assist terminal device 110 in determining whether or not SI is required by terminal device 120, or which type or types of SI are required. After receiving (365) the second information from terminal device 120, terminal device 110 determines (370) whether terminal device 120 needs the SI based on the second information. In some embodiments, terminal device 110 may transmit (350) a request message for the second information to terminal device 120. Upon receiving (355) the request message to terminal device 110, terminal device 120 may transmit the second information to terminal device 110. In other embodiments, terminal device 110 may not have to send such a request message.

In some embodiments, the second information may be similar to the first information, but related to the terminal device 120. For example, the second information may include network connection status information of the terminal device 120, which indicates the network connection status of the terminal device 120. For example, the network connection state information may indicate in which RRC state (RRC connected state, RRC idle state, or RRC inactive state) the terminal device 120 is in an IC state or an OOC state. Specific examples of these network connection states have been discussed above and will not be described herein for brevity.

In some embodiments, based on the network connection status information of terminal device 120, terminal device 110 may determine whether the network connection status of terminal device 120 and terminal device 110 are the same. In some embodiments, terminal device 110 may determine that terminal device 120 requires the SI of network device 130 if the network connection states are different. For example, in a case where the network connection states are different, the terminal device 110 may be able to provide more SI that the terminal device 120 cannot obtain but needs to provide to the terminal device 120. In some embodiments, if the network connection status information of the terminal device 120 indicates that the terminal device 120 is in an OOC state, this means that the terminal device 120 may not be in the coverage of any network device, not in the coverage of a network device that supports sidelink communications, or specifically not in the coverage of the network device 130. Accordingly, the terminal device 110 may determine that the terminal device 120 needs to forward the SI of the network device 130, in particular multiple types of SI, to it by the terminal device 110, so that the terminal device 120 cannot receive messages from the network device 130 at this time.

Alternatively or additionally, the second information may also include cell identification information (e.g., cell ID) corresponding to the terminal device 120. In some embodiments, terminal device 110 may also determine whether the cell identification information corresponding to terminal device 120 is different from the cell identification information corresponding to terminal device 110 based on the cell identification information. Terminal device 110 is typically located within cell 102 of network device 130 and thus its cell identification information may identify cell 102. If terminal device 120 roams into the vicinity of cell 102 but is not connected to or camped on network device 130, the recorded cell identification information may be the cell to which it previously connected or camped on. In this case, terminal device 110 may determine that terminal device 120 needs the SI of network device 130 to be forwarded by network terminal device 110.

In some cases, based on network connection state information and/or cell identification information, terminal device 110 may determine whether terminal device 120 requires a minimum SI, e.g., MIB and/or SIB1. For example, if the network connection status information indicates that the network connection status of terminal device 110 and terminal device 120 are different, and/or if the cell identification information indicates that the cell identifications of terminal device 110 and terminal device 120 correspond are different, terminal device 110 may determine that terminal device 120 requires one or both of MIB and SIB1. In some embodiments, based on network connection state information and/or cell identification information, terminal device 110 may determine that terminal device 120 requires multiple types of SI including MIB, SIB1, and other SIBs. Accordingly, terminal device 110 may decide to transmit a corresponding type of SI to terminal device 120.

In addition to or as an alternative to the network connection status information and the cell identification information, the second information may also include validity related information corresponding to one or more types of SI for use in determining whether one or more types of SI that the terminal device 120 has stored are still valid. In some embodiments, the validity-related information in the second information may comprise validity-related information corresponding to one or more types of SI already stored at the terminal device 120. Examples of validity-related information may be, for example, one or more of those parameters discussed above with reference to fig. 3A, including validity time information corresponding to one or more types of SI, and/or one or more of the following parameters for determining the validity of one or more types of SI: 1) Region range information (denoted as area scope) of the corresponding type of SI, which indicates whether the corresponding type of SI is specific to a certain region, and if the region range information does not exist, may indicate that the corresponding type of SI is cell-specific; 2) Area identification information (denoted as systemlnformationareaid) of the corresponding type of SI for identifying an area to which the corresponding type of SI is specific, the area identification information may be unique under one Public Land Mobile Network (PLMN); 3) Cell identification information of the corresponding type of SI, for indicating a corresponding cell ID; 4) PLMN identification information of the corresponding type of SI may be, for example, a first PLMN ID in a PLMN ID list included in SIB 1; 5) The value label information (denoted as value) of the SI of the corresponding type may be an integer value in a certain range, for example, may take values from 0 to 31, and different values may indicate different versions of the corresponding SI.

In some embodiments, for one or more types of SI, terminal device 110 may compare the parameters corresponding to the SI most recently acquired from network device 130 with the corresponding parameters in the validity-related information included in the second information to determine whether the SI stored at terminal device 120 is still valid. The specific validity determination may refer to the example discussed in the embodiment of fig. 3A. The difference is that this decision process is performed at the terminal device 110.

In some embodiments, if terminal device 110 determines that one or more types of SI stored at terminal device 120 are invalid based on validity time information and/or other parameters, it may be determined that terminal device 120 requires those types of SI. Accordingly, terminal device 110 may decide to transmit the corresponding type of SI to terminal device 120.

In some embodiments, the second information may be carried in various messages sent from terminal device 120 to terminal device 110. Examples of such messages include, but are not limited to: the request message sent in the device discovery process, the direct connection communication request message, the direct connection safety mode completion message, the direct connection safety mode command message or the direct connection communication acceptance message sent in the side link connection establishment process, and the PC5-S message, the PC5-RRC message and the like sent after the side link connection is established. It should be understood that only a few examples are given here, and that other messages communicated from terminal device 120 to terminal device 110 may also be used to carry the second information, or that one or more dedicated messages may be designed to convey the second information or a particular type of second information. Embodiments of the present application are not limited in this respect.

In some embodiments, the request message for the second information may be carried in various messages sent from terminal device 110 to terminal device 120. Examples of such messages include, but are not limited to: a notification message sent by terminal device 110 in the device discovery process, a response message corresponding to the request message sent by terminal device 120; a direct connection security mode command message, a direct connection communication acceptance message, a direct connection communication request message, or a direct connection security mode completion message, which is sent by the terminal device 110 in the connection establishment process; PC5-S messages, PC5-RRC messages after sidelink connection establishment, etc. It should be understood that only a few examples are given here, and that other messages communicated from terminal device 110 to terminal device 120 may also be used to carry the request message for the second information, or one or more dedicated messages may be designed to transmit the request message for the second information. Embodiments of the present application are not limited in this respect.

Above, through various embodiments, how terminal device 110 determines the need or interest of terminal device 120 for one or more types or all types of SI through indication information and/or other information from terminal device 120 is discussed. Thus, terminal device 110 may always transmit SI that it needs or is interested in to terminal device 120.

In some embodiments, after sending the SI once to terminal device 120, terminal device 110 may send the SI of the corresponding type again to terminal device 120 after receiving an update of the SI of the type from network device 130. Still alternatively, terminal device 110 may determine (260) whether the corresponding SI is still valid based on validity-related information corresponding to one or more types of SI previously transmitted, as described in fig. 2. The validity of the SI may be determined based on any of the manners discussed above. If it is determined based on the validity-related information that the previously sent SI is already invalid or about to be invalid, the terminal device 110 may again transmit 265 the SI of the corresponding type to the terminal device 120. The terminal device 120 may thus receive (270) a valid SI.

In some embodiments, terminal device 110 may send updated or valid SI to terminal device 120 multiple times after receiving a long-term indication from terminal device 120 that some type or types of SI are needed. In some embodiments, terminal device 110 may also be configured to transmit the SI multiple times without receiving an explicit long-term indication such as a preamble. For example, if terminal device 120 indicates or terminal device 120 itself determines that one or more other SIBs are of interest to terminal device 120, terminal device 110 may always determine that an updated or valid SI needs to be continuously transmitted to terminal device 110, since these SIBs may be updated or may become invalid by network device 130.

It should be understood that in the signaling diagrams of fig. 2, 3A, and 3B, the ordering of signaling from top to bottom does not necessarily imply a sequential order of the signaling. The order of execution of certain signaling may vary or may be performed in parallel, depending on the particular implementation and actual needs. Although how information (e.g., SI) from a network device is transmitted between terminal devices is described with reference to fig. 1, embodiments of the present application may also be similarly applied to other communication scenarios, such as a UE-to-UE relay scenario. In such a scenario, the first terminal device is configured to relay information from another device (e.g., a third terminal device) to the second terminal device. Such information may be control information or other information that may be transmitted periodically or updated on an irregular basis. By the embodiment of the application, the first terminal equipment can forward or relay the information to the second terminal equipment only when the second terminal equipment needs the information, so that unnecessary signaling transmission and resource overhead are avoided, and the communication quality is improved.

Example method

Fig. 4 illustrates a flow chart of a communication method 400 implemented at a first terminal device according to some embodiments of the present application. The method 400 may be implemented, for example, by the terminal device 110 of fig. 1 (hereinafter referred to as the first terminal device), and accordingly, the second terminal device may be, for example, the terminal device 120 of fig. 1.

At block 410, the first terminal device determines whether the second terminal device requires system information from the network device. If it is determined that the second terminal device requires system information, the first terminal device transmits the system information to the second terminal device via a sidelink connection, which is a communication connection established between the first terminal device and the second terminal device, at block 420.

In some embodiments, determining whether the second terminal device requires system information comprises: the first terminal equipment receives indication information from the second terminal equipment; and the first terminal device determines that the second terminal device requires the system information based on the indication information.

In some embodiments, the indication information comprises at least one of the following: the first indication is used for indicating that the second terminal equipment needs the system information of a plurality of types, and the second indication is used for indicating that the second terminal equipment needs at least one type of the system information of the plurality of types.

In some embodiments, the method 400 further comprises: the first terminal equipment transmits first information to the second terminal equipment, the first information is used for assisting the second terminal equipment to determine the indication information, and the first information comprises at least one of the following items: the network connection state information of the first terminal device, the cell identification information corresponding to the first terminal device, and the validity related information corresponding to at least one type of system information in the plurality of types of system information.

In some embodiments, determining whether the second terminal device requires system information comprises: the first terminal device receives second information from the second terminal device, the second information including at least one of: network connection state information of a second terminal device, cell identification information corresponding to the second terminal device, and validity related information corresponding to at least one type of system information in the plurality of types of system information; and the first terminal device determines whether the second terminal device needs the system information based on the second information.

In some embodiments, the validity-related information comprises at least one of: valid time information for indicating validity duration or validity remaining time of the corresponding system information; region range information for corresponding system information; region identification information for corresponding system information; cell identification information corresponding to the first terminal device; public Land Mobile Network (PLMN) identification information for corresponding system information; and numerical label information for corresponding system information.

In some embodiments, determining whether the second terminal device requires system information based on the second information comprises: the first terminal device determines that the second terminal device requires system information based on at least one of: the network connection state information indicates that the second terminal device is in an out-of-coverage (OOC) state, and the cell identification information corresponding to the second terminal device is different from the cell identification information corresponding to the first terminal device.

In some embodiments, determining whether the second terminal device requires system information based on the second information comprises: the first terminal device determines whether at least one type of system information currently stored at the second terminal device is valid based on the validity-related information; and if the currently stored at the second terminal equipment is determined to be invalid, the first terminal equipment determines that the second terminal equipment needs the at least one type of system information.

In some embodiments, transmitting the system information to the second terminal device comprises: if it is determined that the second terminal device requires at least one type of system information among the plurality of types of system information and the first terminal device does not store at least one type of valid system information, the first terminal device requests the network device for at least one type of system information; the first terminal equipment receives at least one type of system information from the network equipment; and the first terminal device transmitting at least one type of system information to the second terminal device.

In some embodiments, the method 400 further comprises: the method comprises the steps that a first terminal device determines valid time information corresponding to system information which is transmitted to a second terminal device, wherein the valid time information is used for indicating validity duration or validity residual time of the system information; and if the validity duration of the system information reaches a first threshold or the validity remaining time reaches a second threshold, the first terminal device transmits additional system information to the second terminal device.

Fig. 5 illustrates a flow chart of a communication method implemented at a second terminal device according to some embodiments of the present application. The method 500 may be implemented, for example, by the terminal device 120 of fig. 1 (hereinafter referred to as the second terminal device), and accordingly, the first terminal device may be, for example, the terminal device 110 of fig. 1.

At block 510, the second terminal device performs a setup procedure for a sidelink connection with the first terminal device, the sidelink connection being used at least for relaying, by the first terminal device, information from the network device to the second terminal device. In block 520, where it is determined that the second terminal device requires system information, the second terminal device receives the system information from the first terminal device via a sidelink connection.

In some embodiments, receiving system information comprises: the second terminal equipment transmits the indication information to the first terminal equipment so as to indicate the first terminal equipment that the second terminal equipment needs system information; and the second terminal device receives the system information from the second terminal device based on the transmission of the indication information.

In some embodiments, transmitting the indication information comprises: if the second terminal device is in an out-of-coverage (OOC) state, the second terminal device determines that system information is needed; and transmitting the indication information to the first terminal device.

In some embodiments, the method 500 further comprises: the second terminal device receives first information from the first terminal device, the first information including at least one of: the method comprises the steps that network connection state information of first terminal equipment, cell identification information corresponding to the first terminal equipment and validity related information corresponding to at least one type of system information in a plurality of types of system information are obtained; determining that the second terminal device requires system information based on the first information; and generating the indication information based on the determination.

In some embodiments, determining that the second terminal device requires system information based on the first information comprises: the second terminal device determines that the second terminal device requires system information based on at least one of: the network connection state information of the first terminal device is different from the network connection state information of the second terminal device, and the cell identification information corresponding to the second terminal device is different from the cell identification information corresponding to the first terminal device.

In some embodiments, determining that the second terminal device requires system information based on the first information comprises: the second terminal device determines whether at least one type of system information currently stored at the second terminal device is valid based on the validity-related information; and if the at least one type of system information currently stored at the second terminal device is determined to be invalid, the second terminal device determines that the at least one type of system information is required by the second terminal device.

In some embodiments, the method 500 further comprises: the second terminal device transmits second information to the first terminal device, the second information is used for assisting the first terminal device to determine whether the second terminal device needs system information, and the second information comprises at least one of the following items: the network connection state information of the second terminal device, the cell identification information corresponding to the second terminal device, and the validity related information corresponding to at least one type of system information in the plurality of types of system information.

In some embodiments, the validity-related information comprises at least one of: valid time information indicating validity duration or validity remaining time of a specific type of system information, area range information for corresponding system information, area identification information for corresponding system information, cell identification information corresponding to the first terminal device, public Land Mobile Network (PLMN) identification information for corresponding system information, and numerical label information for corresponding system information.

Example apparatus

Fig. 6 illustrates a schematic block diagram of a communication device 600 in accordance with some embodiments of the present application. Communication apparatus 600 may be implemented as a device or chip in a device, although the scope of the present application is not limited in this respect. The communication apparatus 600 may comprise a plurality of modules for performing the corresponding steps in the method 400 as discussed in fig. 4. The communication apparatus 600 may be implemented as the terminal device 110 or a part of the terminal device 110 as shown in fig. 2 to 5.

As shown in fig. 6, the communication apparatus 600 includes a determining unit 610 configured to determine whether the second terminal device needs system information from the network device. The communication apparatus 600 further comprises a first transmission unit 620 configured to transmit the system information to the second terminal device via a sidelink connection if it is determined that the second terminal device requires the system information, the sidelink connection being a communication connection established between the first terminal device and the second terminal device.

In some embodiments, the determining unit 610 includes: a first receiving unit configured to receive indication information from a second terminal device; and an instruction-based determination unit configured to determine that the second terminal device requires the system information based on the instruction information.

In some embodiments, the apparatus 600 further comprises: a second transmission unit configured to transmit first information to the second terminal device, the first information being used to assist the second terminal device in determining the indication information, and the first information including at least one of: the network connection state information of the first terminal device, the cell identification information corresponding to the first terminal device, and the validity related information corresponding to at least one type of system information in the plurality of types of system information.

In some embodiments, the determining unit 610 includes: a second receiving unit configured to receive second information from a second terminal device, the second information including at least one of: network connection state information of a second terminal device, cell identification information corresponding to the second terminal device, and validity related information corresponding to at least one type of system information in the plurality of types of system information; and an information-based determination unit configured to determine whether the second terminal device requires the system information based on the second information.

In some embodiments, the validity-related information comprises at least one of: valid time information indicating validity duration or validity remaining time of the corresponding system information, area range information for the corresponding system information, area identification information for the corresponding system information, cell identification information corresponding to the first terminal device, public Land Mobile Network (PLMN) identification information for the corresponding system information, and numerical label information for the corresponding system information.

In some embodiments, the information-based determination unit comprises: a determination unit based on the state information, configured to determine, by the first terminal device, that the second terminal device requires the system information based on at least one of: the network connection state information indicates that the second terminal device is in an out-of-coverage (OOC) state, and the cell identification information corresponding to the second terminal device is different from the cell identification information corresponding to the first terminal device.

In some embodiments, the information-based determination unit comprises: a validity determining unit configured to determine whether at least one type of system information currently stored at the second terminal device is valid based on the validity-related information; and a validity-based determination unit configured to determine, by the first terminal device, that the second terminal device requires at least one type of system information if it is determined that the at least one type of system information currently stored at the second terminal device is invalid.

In some embodiments, the first transmission unit 620 includes: a requesting unit configured to request the network device for at least one type of system information by the first terminal device if it is determined that the second terminal device requires at least one type of system information among the plurality of types of system information and the first terminal device does not store valid system information of the at least one type; a third receiving unit configured to receive at least one type of system information from the network device; and a third transmission unit configured to transmit the at least one type of system information to the second terminal device.

In some embodiments, communications apparatus 600 further comprises: a valid time determination unit configured to determine valid time information corresponding to the system information that has been transmitted to the second terminal device, the valid time information indicating validity duration or validity remaining time of the system information; and a fourth transmission unit configured to transmit the additional system information to the second terminal device by the first terminal device if the validity duration of the system information reaches the first threshold or the validity remaining time reaches the second threshold.

Fig. 7 illustrates a schematic block diagram of a communication apparatus 700 according to some embodiments of the present application. Communication apparatus 700 may be implemented as a device or chip in a device, although the scope of the application is not limited in this respect. The communication apparatus 700 may include a number of modules for performing the corresponding steps in the method 500 as discussed in fig. 5. The communication apparatus 700 may be implemented as the second terminal device 120 or a part of the second terminal device 120 as shown in fig. 2 to 5.

As shown in fig. 7, the communication apparatus 700 comprises a connection establishing unit 710 configured to perform a setup procedure of a sidelink connection with the first terminal device, the sidelink connection being at least used for relaying, by the first terminal device, information from the network device to the second terminal device. The communication apparatus 700 further comprises a first receiving unit 720 configured to receive the system information from the first terminal device via the sidelink connection by the second terminal device, in case it is determined that the system information is required by the second terminal device.

In some embodiments, the communications apparatus 700 further comprises: a first transmission unit configured to transmit indication information to the first terminal device to indicate to the first terminal device that the second terminal device requires system information; and wherein the first receiving unit 720 is configured to receive the system information from the second terminal device based on the transmission of the indication information.

In some embodiments, the first transmission unit comprises: a first need determining unit configured to determine, by the second terminal device, that system information is needed if the second terminal device is in an out-of-coverage (OOC) state; and a transmission unit determined based on the need, configured to transmit the indication information to the first terminal device.

In some embodiments, the communications apparatus 700 further comprises: a second receiving unit configured to receive first information from the first terminal device, the first information including at least one of: the method comprises the steps that network connection state information of first terminal equipment, cell identification information corresponding to the first terminal equipment and validity related information corresponding to at least one type of system information in a plurality of types of system information are obtained; a second need determination unit configured to determine that the second terminal device needs the system information based on the first information; and an indication generating unit configured to generate the indication information based on the determination.

In some embodiments, the second need determining unit includes: an information-based determination unit configured to determine that the second terminal device requires system information based on at least one of: the network connection state information of the first terminal device is different from the network connection state information of the second terminal device, and the cell identification information corresponding to the second terminal device is different from the cell identification information corresponding to the first terminal device.

In some embodiments, the second need determining unit includes: a validity determining unit configured to determine whether at least one type of system information currently stored at the second terminal device is valid based on the validity-related information; and a validity-based determination unit configured to determine that the second terminal device requires at least one type of system information if it is determined that the at least one type of system information currently stored at the second terminal device is invalid.

In some embodiments, the communications apparatus 700 further comprises: a second transmission unit configured to transmit second information to the first terminal device, the second information being used to assist the first terminal device in determining whether the second terminal device requires system information, and the second information including at least one of: the network connection state information of the second terminal device, the cell identification information corresponding to the second terminal device, and the validity related information corresponding to at least one type of system information in the plurality of types of system information.

Example apparatus

Fig. 8 is a simplified block diagram of an example device 800 suitable for implementing embodiments of the present application. Device 800 may be used to implement terminal device 110, terminal device 120, or network device 130 as shown in fig. 1. As shown, device 800 includes one or more processors (or processing units) 810, may also include one or more memories 820 coupled to processors 810, and may also include a communication interface 840 coupled to processors 810.

Communication interface 840 may be used for two-way communication. Communication interface 840 may have at least one communication interface for communicating. The communication interface may include any interface necessary to communicate with other devices.

The processor 810 may be of any type suitable for a local technology network, and may include, but is not limited to, at least one of: one or more of a general purpose computer, a special purpose computer, a microcontroller, a digital signal controller (DSP), or a controller-based multi-core controller architecture. The device 800 may have multiple processors, such as application specific integrated circuit chips, that are time dependent from a clock synchronized with the main processor.

The memory 820 may include one or more non-volatile memories and one or more volatile memories. Examples of non-volatile memory include, but are not limited to, at least one of the following: read-only memory (ROM) 824, erasable programmable read-only memory (EPROM), flash memory, a hard disk, a Compact Disc (CD), a Digital Video Disc (DVD), or other magnetic and/or optical storage. Examples of volatile memory include, but are not limited to, at least one of: random Access Memory (RAM) 822, or other volatile memory that does not persist for the duration of the power down.

The computer programs 830 include computer-executable instructions that are executed by the associated processor 810. The program 830 may be stored in the ROM 820. Processor 810 may perform any suitable acts and processes by loading programs 830 into RAM 820.

Embodiments of the present application may be implemented by way of program 830 such that device 800 may perform any of the processes as discussed with reference to fig. 2-7. Embodiments of the present application may also be implemented by hardware or by a combination of software and hardware.

In some embodiments, the program 830 may be tangibly embodied in a computer-readable medium, which may be included in the device 800 (such as in the memory 820) or other storage device accessible by the device 800. Program 830 can be loaded into RAM 822 from a computer-readable medium for execution. The computer readable medium may include any type of tangible, non-volatile memory, such as ROM, EPROM, flash memory, a hard disk, a CD, a DVD, etc.

In general, the various embodiments of the application may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software, which may be executed by a controller, microprocessor or other computing device. While various aspects of the embodiments of the present application are illustrated and described as block diagrams, flow charts, or using some other pictorial representation, it is well understood that the blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

The present application also provides at least one computer program product tangibly stored on a non-transitory computer-readable storage medium. The computer program product comprises computer executable instructions, such as instructions included in program modules, which are executed in a device on a real or virtual processor of the target to perform the processes/methods as described above with reference to fig. 2-7. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, etc. that perform particular tasks or implement particular abstract data types. In various embodiments, the functionality of the program modules may be combined or split between program modules as desired. Machine-executable instructions for program modules may be executed within a local or distributed device. In a distributed facility, program modules may be located in both local and remote memory storage media.

Program code for implementing the methods of the present application may be written in any combination of one or more programming languages. These program code may be provided to a processor or controller of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program code, when executed by the processor or controller, causes the functions/acts specified in the flowchart and/or block diagram to be performed. The program code may execute entirely on the machine, partly on the machine, as a stand-alone software package partly on the machine and partly on a remote machine or entirely on the remote machine or server.

In the context of this application, a machine-readable medium may be a tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device. The machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of a machine-readable storage medium would include an electrical connection based on one or more wires, a portable computer diskette, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

Further, while operations are depicted in a particular order, this should be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. Under certain circumstances, multitasking and parallel processing may be advantageous. Likewise, while several specific implementation details are included in the above discussion, these should not be construed as limitations on the scope of the application. Certain features that are described in the context of separate embodiments can also be implemented in combination in a single implementation. Conversely, various features that are described in the context of a single implementation can also be implemented in multiple implementations separately or in any suitable subcombination.

Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

1. A method of communication, comprising:

the first terminal equipment determines whether the second terminal equipment needs system information from the network equipment; and

and if the second terminal equipment needs the system information, the first terminal equipment transmits the system information to the second terminal equipment through a sidelink connection, wherein the sidelink connection is a communication connection established between the first terminal equipment and the second terminal equipment.

2. The method of claim 1, wherein determining whether the system information is needed by the second terminal device comprises:

the first terminal equipment receives indication information from the second terminal equipment; and

the first terminal device determines that the second terminal device requires the system information based on the indication information.

3. The method of claim 2, wherein the indication information comprises at least one indication of:

a first indication indicating that the second terminal device requires a plurality of types of system information, an

A second indication indicating that the second terminal device requires at least one type of system information of a plurality of types of system information.

4. The method of claim 2 or 3, further comprising:

the first terminal device transmits first information to the second terminal device, the first information is used for assisting the second terminal device to determine the indication information, and the first information comprises at least one of the following items:

network connection status information of the first terminal device,

cell identification information corresponding to the first terminal device, and

validity-related information corresponding to at least one type of system information among the plurality of types of system information.

5. The method of claim 1, wherein determining whether the system information is needed by the second terminal device comprises:

the first terminal device receiving second information from the second terminal device, the second information including at least one of:

network connection status information of the second terminal device,

cell identification information corresponding to the second terminal device, and

validity-related information corresponding to at least one type of system information among the plurality of types of system information; and the first terminal device determines whether the second terminal device needs the system information based on the second information.

6. The method according to claim 4 or 5, wherein the validity-related information comprises at least one of:

validity time information indicating a validity duration or a validity remaining time of the corresponding system information,

with respect to the area range information corresponding to the system information,

with respect to the area identification information of the corresponding system information,

cell identification information corresponding to the first terminal device,

public Land Mobile Network (PLMN) identification information for corresponding system information, and

numerical label information for corresponding system information.

7. The method of claim 5 or 6, wherein determining whether the system information is needed by the second terminal device based on the second information comprises:

the first terminal device determines that the system information is needed by the second terminal device based on at least one of:

the network connection status information indicates that the second terminal device is in an out-of-coverage (OOC) state, an

The cell identification information corresponding to the second terminal device is different from the cell identification information corresponding to the first terminal device.

8. The method of claim 5 or 6, wherein determining whether the system information is needed by the second terminal device based on the second information comprises:

the first terminal device determining whether the at least one type of system information currently stored at the second terminal device is valid based on the validity-related information; and

if the currently stored system information of at least one type at the second terminal device is determined to be invalid, the first terminal device determines that the system information of at least one type is needed by the second terminal device.

9. The method of any of claims 1 to 8, wherein transmitting the system information to the second terminal device comprises:

if it is determined that the second terminal device requires at least one type of system information among a plurality of types of system information and the first terminal device does not store valid system information of the at least one type, the first terminal device requests the network device for the at least one type of system information;

the first terminal device receiving the at least one type of system information from the network device; and

the first terminal device transmits the at least one type of system information to the second terminal device.

10. The method of any of claims 1 to 9, further comprising:

the first terminal device determines valid time information corresponding to the system information transmitted to the second terminal device, wherein the valid time information is used for indicating validity duration or validity remaining time of the system information; and

and if the validity duration of the system information reaches a first threshold value or the validity residual time reaches a second threshold value, the first terminal equipment transmits additional system information to the second terminal equipment.

11. A method of communication, comprising:

the second terminal device executes a process of establishing a sidelink connection with the first terminal device, the sidelink connection being at least used for relaying information from the network device to the second terminal device by the first terminal device; and

and under the condition that the second terminal equipment needs the system information, the second terminal equipment receives the system information from the first terminal equipment through the side link connection.

12. The method of claim 11, wherein receiving the system information comprises:

the second terminal device transmits indication information to the first terminal device so as to indicate to the first terminal device that the second terminal device needs the system information; and

the second terminal device receives the system information from the second terminal device based on the transmission of the indication information.

13. The method of claim 12, wherein the indication information comprises at least one indication of:

A second indication indicating that the second terminal device requires at least one type of system information of the plurality of types of system information.

14. The method of claim 12 or 13, wherein transmitting the indication information comprises:

if the second terminal device is in an out-of-coverage (OOC) state, the second terminal device determines that the system information is needed; and

and the second terminal equipment transmits the indication information to the first terminal equipment.

15. The method of any of claims 12 to 14, further comprising:

the second terminal device receives first information from the first terminal device, the first information including at least one of:

network connection status information of the first terminal device,

cell identification information corresponding to the first terminal device, and

validity related information corresponding to at least one type of system information in the multiple types of system information;

the second terminal device determining that the second terminal device requires the system information based on the first information; and

the second terminal device generates the indication information based on the determination.

16. The method of claim 15, wherein determining that the system information is needed by the second terminal device based on the first information comprises:

the second terminal device determines that the system information is needed by the second terminal device based on at least one of:

the network connection status information of the first terminal device is different from the network connection status information of the second terminal device, an

17. The method of claim 15, wherein determining that the system information is needed by the second terminal device based on the first information comprises:

the second terminal device determining whether the at least one type of system information currently stored at the second terminal device is valid based on the validity-related information; and

if the currently stored system information of at least one type at the second terminal device is determined to be invalid, the second terminal device determines that the system information of at least one type is needed by the second terminal device.

18. The method of claim 11, further comprising:

the second terminal device transmits second information to the first terminal device, the second information being used to assist the first terminal device in determining whether the system information is needed by the second terminal device, and the second information including at least one of:

network connection status information of the second terminal device,

19. The method according to claim 15 or 18, wherein the validity related information comprises at least one of:

validity time information indicating a validity duration or a validity remaining time of the specific type of system information,

cell identification information corresponding to the first terminal device,

numerical label information for corresponding system information.

20. A communication apparatus implemented at a first terminal device, comprising:

a determination unit configured to determine whether the second terminal device requires system information from the network device; and

a first transmission unit configured to, if it is determined that the system information is required by the second terminal device, transmit the system information to the second terminal device via a sidelink connection, which is a communication connection established between the first terminal device and the second terminal device.

21. A communication apparatus implemented at a second terminal device, comprising:

a connection establishing unit configured to perform a setup procedure of a sidelink connection with a first terminal device, the sidelink connection being at least used for relaying, by the first terminal device, information from a network device to the second terminal device; and

a first receiving unit configured to receive the system information from the first terminal device via the sidelink connection by the second terminal device, in a case where it is determined that the system information is required by the second terminal device.

22. A communication apparatus implemented at a first terminal device, comprising:

at least one processing unit; and

at least one memory coupled to the at least one processing unit and storing instructions for execution by the at least one processing unit, the instructions when executed by the at least one processing unit cause the communication device to implement the operations of the method of any of claims 1 to 10.

23. A communication apparatus implemented at a second terminal device, comprising:

at least one processing unit; and

at least one memory coupled to the at least one processing unit and storing instructions for execution by the at least one processing unit, the instructions when executed by the at least one processing unit cause the communication device to implement the operations of the method of any of claims 11 to 19.

24. A communication system, comprising:

at least one communication device according to claim 20 or 22; and

at least one communication device according to claim 21 or 23.

25. A computer readable storage medium having stored thereon a computer program which, when executed by a processor, performs operations according to the method of any one of claims 1 to 10 or the method of any one of claims 11 to 19.

26. A computer program product tangibly stored on a computer-readable medium and comprising computer-executable instructions that, when executed, cause an apparatus to perform operations of a method of any of claims 1 to 10 or of any of claims 11 to 19.

27. A chip configured to perform the operations of the method of any of claims 1 to 10 or the operations of the method of any of claims 11 to 19.