Communication device, communication method, transmission device and reception device

Cooperative V2X communication in a system wherein a network device (base station or road side unit RSU) transmits to a terminal device a signal indicating whether the network device supports cooperative V2X transmission of messages from the terminal device to a vehicle-mounted terminal device; and performs cooperative V2X communication by transmitting to the vehicle-mounted terminal device a message intended for it that is received from the terminal device; and wherein the terminal device determines whether the network device supports cooperative V2X communication based on the signal received from the network device; and, based on the determination, performs cooperative V2X communication with the vehicle-mounted terminal device with support from the network device by transmitting a message directly to the vehicle-mounted terminal device and transmitting the message intended for the vehicle-mounted terminal device to the network device.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of Japanese Priority Patent Application JP 2016-020196 filed Feb. 4, 2016, the entire contents of which are incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to a communication device, a communication method, a transmission device and a reception device.

BACKGROUND ART

By utilizing a communication device onboard a moving object such as a vehicle, direct communication between the moving object and various target objects is realized. Communication between a communication device onboard a moving object and various other communication devices is called vehicle-to-X (V2X) communication. For V2X communication, communication systems utilizing dedicated short range communications (DSRC) have been investigated thus far, but recently, investigation into communication systems utilizing mobile phone communication standards such as Long Term Evolution (LTE) is progressing. A system related to the LTE communication standard is disclosed in NPL 1 below, for example.

CITATION LIST

Non Patent Literature

SUMMARY

Technical Problem

In V2X communication, a communication device carried by a pedestrian, a communication device mounted on a moving object and a communication device installed on the side of a road exchange messages with one another to realize improvement of convenience of transportation and assurance of safety. However, considering that the quantity of power of a communication device carried by a pedestrian is restricted and a communication device mounted on a moving object may move at a high speed and the like, it is desirable that retransmission according to failure of transmission and reception of a message not be performed when possible. Therefore, the present disclosure provides a system capable of achieving successful transmission and reception of messages in V2X communication more reliably.

Solution to Problem

According to a first embodiment, the disclosure is directed to an electronic device including: circuitry configured to receive a signal from at least one of a base station or road side unit (RSU); determine whether the a least one of the base station or RSU support cooperative vehicle-to-X (V2X) communication; and perform cooperative V2X communication with a vehicle-mounted electronic device with support from the at least one of the base station or RSU based on the determination.

According to another exemplary embodiment, the disclosure is directed to a method performed by an electronic device, the method including: receiving a signal from at least one of a base station or road side unit (RSU); determining whether the a least one of the base station or RSU support cooperative vehicle-to-X (V2X) communication; and performing V2X communication with a vehicle-mounted electronic device with support from the at least one of the base station or RSU based on the determination.

According to another exemplary embodiment, the disclosure is directed to a system including: a network device including first circuitry configured to transmit a signal to a terminal device indicating whether the network device supports cooperative vehicleto-X (V2X) transmission of messages from the terminal device to a vehicle-mounted terminal device; receive, from the terminal device, a message intended for the vehicle-mounted terminal device; and perform cooperative V2X communication with the vehicle-mounted terminal device by transmitting the message received from the terminal device to the vehicle-mounted terminal device.

The system may also include the terminal device including second circuitry configured to receive the signal from the network device indicating whether the network device supports cooperative vehicle-to-X (V2X) transmission of messages from the terminal device to the vehicle-mounted terminal device; determine whether the network device supports cooperative vehicle-to-X (V2X) communication; and perform cooperative V2X communication with the vehicle-mounted electronic device with support from the network device based on the determination.

Advantageous Effects of Invention

According to an embodiment of the present disclosure described above, a system capable of achieving successful transmission and reception of messages in V2X communication more reliably is provided. Note that the effects described above are not necessarily limitative. With or in the place of the above effects, there may be achieved any one of the effects described in this specification or other effects that may be grasped from this specification.

DESCRIPTION OF EMBODIMENTS

Also, in this specification and the appended drawings, multiple structural elements having substantially the same function and structure may in some cases be distinguished by different letters appended to the same sign. For example, multiple elements having substantially the same function and structure or logical significance are distinguished as UEs10A,10B,10C, and so on as necessary. On the other hand, when not particularly distinguishing each of multiple structural elements having substantially the same function and structure, only the same sign will be given. For example, when not particularly distinguishing UEs10A,10B,10C, each of the UEs10A,10B,10C will be designated simply the UE10.

Hereinafter, a description will be given in the following order.

1.2. Technical Problem

2. Examples of Configuration

2.1. Example of Configuration of System

2.2. Example of Configuration of UE (user equipment)

2.3. Example of Configuration of UE (moving object)

2.4. Example of Configuration of eNB

2.5. Example of Configuration of RSU

3. Technical Features

3.1. Basic Operation

3.2.2. Cooperative Transmission Types

3.2.3. Processing Flows

4. Application Examples

By utilizing a communication device onboard a moving object such as a vehicle, direct communication between the moving object and various target objects is realized. Communication between a vehicle and various target objects is called vehicle-to-X (V2X) communication.FIG. 1is an explanatory diagram for describing an overview of V2X communication. As illustrated inFIG. 1, V2X communication may be vehicleto-vehicle (V2V) communication, vehicle-to-infrastructure (V2I) communication, vehicle-to-pedestrian (V2P) communication, or vehicle-to-home (V2H) communication, for example. In addition, while not illustrated, V2X communication also includes vehicle to nomadic device (V2N) communication, for example. Here, the first character and the third character of V2V communication and the like respectively mean a start point and an end point and do not limit communication paths. For example, V2V communication is the concept including direct communication between moving objects and indirect communication view a base station.

As illustrated inFIG. 1, the communication target of a vehicle in V2V communication may be a passenger vehicle, a commercial or fleet vehicle, an emergency vehicle, or a transit vehicle, for example. Also, the communication target of a vehicle in V2I communication may be a cellular network, a data centre, a fleet or freight management centre, a traffic management centre, a weather service, a rail operation centre, a parking system, or a toll system, for example. Also, the communication target of a vehicle in V2P communication may be a cyclist, a pedestrian shelter, or a motorcycle, for example. Also, the communication target of a vehicle in V2H communication may be a home network, a garage, or enterprise or dealer networks, for example.

Note that in V2X communication, communication systems utilizing dedicated short range communications (DSRC) have been investigated, but recently, investigation into communication systems utilizing mobile phone communication standards such as Long Term Evolution (LTE) is progressing.

Examples of applications of V2X communication include communication systems intended for forward collision warning, loss of control warning, emergency vehicle warning, emergency stop, adaptive cruise assist, traffic condition warning, traffic safety, automatic parking, route deviation warning, message transmission, collision warning, communication range extension, traffic volume optimization, curve speed alert, pedestrian collision warning, or vulnerable person safety. In addition, V2X communication according to user equipment (UE) of a road side unit (RSU) type, minimum QoS of V2X communication, V2X access during roaming, message provision through V2P communication for traffic safety of pedestrians, mixed use for traffic management, improvement of positioning accuracy for traffic participants or the like are investigated.

A list of requirements for the above application examples is shown in the following table1.

To meet the above requirements, standardization of the physical layer of V2X is being investigated in 3GPP. A base technology of V2X communication may be device-to-device (D2D) communication that was standardized in the past in 3GPP. Since D2D communication is communication between terminals without a base station, D2D communication may be considered to aim for extension to V2V communication, V2P communication or part of V2I communication. Such an interface between terminals is called a PC5 interface. For V2I communication or V2N, extension of a previous technology of communication between a base station and a terminal, such as LTE, is being considered. Such an interface between a base station and a terminal is called a Uu interface. In future investigation, it will be necessary to extend the PC5 interface and the Uu interface to meet the above requirements. Main extension points may be, for example, improvement of resource allocation, Doppler frequency measures, establishment of a synchronization method, realization of low power consumption communication, realization of low delay communication and so on.

Various operation scenarios of V2X communication are considered. As an example, examples of operation scenarios of V2V communication will be described with reference toFIGS. 2 to 6.

FIG. 2is an explanatory diagram for describing a first scenario of V2V communication. In the first scenario, moving objects such as vehicles directly perform V2V communication. A communication link in this case may be called sidelink (SL).

FIG. 3is an explanatory diagram for describing a second scenario of V2V communication. In the second scenario, moving objects such as vehicles indirectly perform V2V communication via evolved universal terrestrial radio access (E-UTRAN), that is, a base station. A communication link from a transmitting side to the base station is called uplink (UL) and a communication link from the base station to a receiving side is called downlink (DL).

FIG. 4is an explanatory diagram for describing a third scenario of V2V communication. In the third scenario, a moving object such as a vehicle transmits a signal to other moving objects sequentially through an RSU or a UE of RSU type and E-UTRAN. Communication links between the devices are sequentially called SL, UL and DL.

FIG. 5is an explanatory diagram for describing a fourth scenario of V2V communication. In the fourth scenario, a moving object such as a vehicle transmits a signal to other moving objects sequentially through E-UTRAN and an RSU or a UE of RSU type. Communication links between the devices are sequentially called UL, DL and SL.

FIG. 6is an explanatory diagram for describing a fifth scenario of V2V communication. In the fifth scenario, moving objects such as vehicles indirectly perform V2V communication through an RSU or a UE of RSU type. Communication links between the moving objects and the RSU or UE of RSU type are SL.

The above-described scenarios become scenarios of V2P communication when one of the moving objects is changed to a pedestrian. Similarly, the scenarios become scenarios of V2I communication or V2N communication when one of the moving objects is changed to an infrastructure or a network, respectively.

In V2P communication, communication is performed between a communication device aboard a moving object and a communication device carried by a pedestrian. An example of requirements in V2P communication will be described below. As a relay requirement, delay within 500 ms from a server to a terminal and within 100 ms for end-to-end is considered. As an operation requirement, handling multiple mobile network operators (MNO) is considered. As a power consumption requirement, minimization of battery consumption is considered. As a coverage requirement, coverage of a range in which V2P communication can be performed 4 seconds or longer before collision is considered. For example, in the case of 100 km an hour, coverage having a diameter of approximately 110.8 m or longer corresponding to 27.7 m/s×4 s is necessary. As a message requirement, typically 50 to 300 bytes, and a maximum of 1,200 bytes is considered. As a communication quality requirement, establishment of communication in environments in which a relative speed of a motorcycle and a car is 280 km/h and a relative speed of a pedestrian and a car is 160 km/h is considered.

A technical task of the present disclosure is minimization of battery consumption from among the aforementioned requirements. A smartphone or the like considered as a communication device carried by a pedestrian has insufficient battery capacity in many cases. Accordingly, minimization of battery consumption may be regarded as an important task for introduction of V2P communication.

Here, a communication device carried by a pedestrian has a lower signal transmission frequency than other devices, and thus it is desirable that a receiving side receive signals more reliably. Accordingly, the number of retransmissions is decreased to reduce power consumption of the communication device carried by the pedestrian. Furthermore, a communication device mounted on a moving object may be moved at a high speed, and thus a time lag due to retransmission may cause accidents. Due to such circumstances, the present disclosure provides a system for improving message arrival probability in a reception device by supporting transmission of a transmission device by other communication devices.

2. EXAMPLES OF CONFIGURATION

Hereinafter, examples of a configuration of a wireless communication system according to the present embodiment will be described.

<2.1. Example of Configuration of System>

FIG. 7is an explanatory diagram illustrating a configuration of a wireless communication system according to an embodiment of the present disclosure. As illustrated inFIG. 7, the wireless communication system according to the embodiment of the present disclosure includes a UE10, a UE20, a vehicle22, an eNB30, a GNSS satellite40and an RSU50.

The eNB30is a cellular base station that provides a cellular communication service to the UE20positioned inside a cell. For example, the eNB30schedules resources for the UEs10and20to communicate by, and notifies the UEs10and20of the scheduled resources. Additionally, the eNB30conducts uplink communication or downlink communication with the UEs10and20in the relevant resources.

The GNSS satellite40is an artificial satellite (communication device) that revolves around the earth in a predetermined orbit. The GNSS satellite40transmits a global navigation satellite system (GNSS) signal including a navigation message. The navigation message includes various types of information for positioning, such as orbit information and time information of the GNSS satellite40.

The RSU50is a communication device installed on the side of a road. The RSU50may perform bi-directional communication with the vehicle22, the UE20aboard the vehicle22or the UE10carried by a user12. While the RSU50may perform DSRC with the vehicle22, the UE20aboard the vehicle22or the UE10carried by the user12, the RSU50is assumed to communicate with the vehicle22, the UE20aboard the vehicle22or the UE10carried by the user12through cellular communication system in the present embodiment.

The UE20is a communication device that is mounted on the vehicle22and moves along with traveling of the vehicle22. The UE20has a function of communicating with the eNB30according to control by the eNB30. In addition, the UE20has functions of receiving the GNSS signal transmitted from the GNSS satellite40and measuring location information of the UE20from the navigation message included in the GNSS signal. Further, the UE20has a function of communicating with the RSU50. Moreover, the UE20according to the present embodiment may perform direct communication with the UE10carried by the user12or the UE20aboard another vehicle22, that is, D2D communication. Hereinafter, the UE20and the moving object22are collectively called UE20if the UE20and the moving object22may not be distinguished.

The UE10is a communication device that is carried by the user12and moves along with walking or running of the user12or movement of a vehicle (a bus, a motorcycle, a car or the like) that the user12is riding. The UE10has a function of communicating with the eNB30according to control by the eNB30. In addition, the UE10has functions of receiving the GNSS signal transmitted from the GNSS satellite40and measuring location information of the UE10from the navigation message included in the GNSS signal. Further, the UE10has a function of communicating with the RSU50. Moreover, the UE10according to the present embodiment may perform direct communication with another UE10or the UE20, that is, D2D communication. Communication between the UE10and the UE20is called V2P communication.

Note that althoughFIG. 7illustrates the vehicle22as an example of a moving object, the moving object is not limited to the vehicle22. For example, the moving object may also be an object such as a marine vessel, an aircraft, or a bicycle. In addition, although the above describes the UE20as including the function of receiving the GNSS signal, the vehicle22may have the function of receiving the GNSS signal, and the vehicle22may output a GNSS signal reception result to the UE20.

<2.2. Example of Configuration of UE (User Terminal)>

FIG. 8is a block diagram illustrating an example of a logical configuration of the UE10according to an embodiment of the present disclosure. As illustrated inFIG. 8, the UE10according to the present embodiment includes an antenna part110, a wireless communication unit120, a GNSS signal processing unit130, a storage unit140and a processing unit150.

The antenna part110radiates a signal output from the wireless communication unit120as radio waves to the air. In addition, the antenna part110converts radio waves of the space into a signal and outputs the signal to the wireless communication unit120.

The wireless communication unit120transmits and receives signals. For example, the wireless communication unit120receives a downlink signal from the eNB30and transmits an uplink signal to the eNB30. Furthermore, the wireless communication unit120transmits/receives a sidelink signal to/from another UE10, the UE20or the RSU50.

The GNSS signal processing unit130is a component that processes the GNSS signal transmitted from the GNSS satellite40. For example, the GNSS signal processing unit130measures location information and time information of the UE10by processing the GNSS signal.

The storage unit140stores programs and various types of data for operations of the UE10temporarily or permanently.

The processing unit150provides various functions of the UE10. For example, the processing unit150controls communication performed by the wireless communication unit120.

<2.3. Example of Configuration of UE (Moving Object)>

FIG. 9is a block diagram illustrating an example of a logical configuration of the UE20according to an embodiment of the present disclosure. As illustrated inFIG. 9, the UE20according to the present embodiment includes an antenna part210, a wireless communication unit220, a GNSS signal processing unit230, a storage unit240and a processing unit250.

The antenna part210radiates a signal output from the wireless communication unit220as radio waves to the space. In addition, the antenna part210converts radio waves of the space into a signal and outputs the signal to the wireless communication unit220.

The wireless communication unit220transmits and receives signals. For example, the wireless communication unit220receives a downlink signal from the eNB30and transmits an uplink signal to the eNB30. Furthermore, the wireless communication unit220transmits/receives a side link signal to/from the UE10, another UE20or the RSU50.

The GNSS signal processing unit230is a component that processes the GNSS signal transmitted from the GNSS satellite40. For example, the GNSS signal processing unit230measures location information and time information of the UE20by processing the GNSS signal.

The storage unit240stores programs and various types of data for operations of the UE20temporarily or permanently.

The processing unit250provides various functions of the UE20. For example, the processing unit250controls communication performed by the wireless communication unit220.

<2.4. Example of Configuration of eNB>

FIG. 10is a block diagram illustrating an example of a logical configuration of the eNB30according to an embodiment of the present disclosure. As illustrated inFIG. 10, the eNB30according to the present embodiment includes an antenna part310, a wireless communication unit320, a network communication unit330, a storage unit340and a processing unit350.

The antenna part310radiates a signal output from the wireless communication unit320as radio waves to the space. In addition, the antenna part310converts radio waves of the space into a signal and outputs the signal to the wireless communication unit320.

The wireless communication unit320transmits and receives signals. For example, the wireless communication unit320receives an uplink signal from the UE10, the UE20or the RSU50and transmits a downlink signal to the UE10, the UE20or the RSU50.

The network communication unit330transmits and receives information. For example, the network communication unit330transmits information to other nodes and receives information from other nodes. For example, the other nodes include other base stations and a core network node.

The storage unit340stores programs and various types of data for operations of the eNB30temporarily or permanently.

The processing unit350provides various functions of the eNB30. For example, the processing unit350controls communication performed by the UE10, the UE20and the RSU50subordinate thereto.

<2.5. Example of Configuration of RSU>

FIG. 11is a block diagram illustrating an example of a logical configuration of the RSU50according to an embodiment of the present disclosure. As illustrated inFIG. 11, the RSU50according to the present embodiment includes an antenna part510, a wireless communication unit520, a storage unit530and a processing unit540.

The antenna part510radiates a signal output from the wireless communication unit520as radio waves to the space. In addition, the antenna part510converts radio waves of the space into a signal and outputs the signal to the wireless communication unit520.

The wireless communication unit520transmits and receives signals. For example, the wireless communication unit520receives a downlink signal from the eNB30and transmits an uplink signal to the eNB30. Furthermore, the wireless communication unit520transmits/receives a side link signal to/from the UE10, the UE20or another RSU50.

The storage unit530stores programs and various types of data for operations of the RSU50temporarily or permanently.

The processing unit540provides various functions of the RSU50. For example, the processing unit540controls communication performed by the wireless communication unit520.

Configuration examples which are common in embodiments have been described. Next, technical features of the respective embodiments will be described in detail.

3. TECHNICAL FEATURES

The present embodiment provides a system in which transmission by a transmission device is supported by another communication device (referred to hereinafter as a supporting device) to improve message arrival probability in a reception device.

Hereinafter, an example in which a transmission device is the UE10, a reception device is the UE20and the supporting device is the eNB30or the RSU50will be described. It will be assumed that battery capacity of the UE10is restricted in some cases, whereas the eNB30or the RSU50has sufficient battery capacity or is connected to a power supply. Accordingly, the eNB30or the RSU50supports transmission by the UE10using sufficient power thereof and thus message arrival probability may be improved and power consumption of the UE10may be reduced. Meanwhile, there may be a UE type RSU50and an eNB type RSU50. The UE type RSU50can operate as a UE, supports a PC5 interface between the RSU50and at least another UE and supports a Uu interface between the RSU50and the eNB30. In addition, the eNB type RSU50may operate as an eNB30.

The transmission device, the reception device and the supporting device are not limited to the aforementioned examples. For example, the transmission device may be the UE20and the reception device may be the UE10. Further, both the transmission device and the reception device may be the UE10or the UE20. In addition, the transmission device may be the RSU50. The supporting device may be the UE10or the UE20, and there may be a plurality of supporting devices.

The UE10performs V2X communication with the support of the eNB30or the RSU50when the UE10receives support of the eNB30or the RSU50and performs normal V2X communication when the UE10does not receive support. The former is referred to as V2X communication with support and the latter is referred to as V2X communication without support.

Accordingly, the UE10discovers a neighboring eNB30or RSU50. For example, the UE10may discover the RSU50through a discovery signal or a physical sidelink broadcast channel (PSBCH) from the RSU50. Further, the UE10may discover the eNB30through a physical broadcast channel (PBCH), a physical downlink control channel (PDCCH), a master information block (MIB) or a system information block (SIB) from the eNB30.

Additionally, the UE10checks whether the discovered eNB30or RSU50supports V2X communication with support. For example, the eNB30or the RSU50notifies the UE10of information indicating that a message may be relayed to the UE20by supporting the UE10(e.g., cooperating with the UE10, substituting for the UE10or the like). Specifically, a discovery signal or system information (SIB or MIB) may include information indicating whether V2X communication is supported. Accordingly, the UE10acquires support information from the discovery signal or system information to perform the aforementioned checking.

The UE10performs V2X communication with support when the eNB30or the RSU50supporting V2X communication with support is confirmed and performs V2X communication without support when the eNB30or the RSU50supporting V2X communication with support is not confirmed. Such processing flow will be described with reference toFIG. 12.

FIG. 12is a flowchart illustrating an example of a processing flow of determining start of V2X communication with support performed by a transmission device (e.g., UE10) according to the present embodiment. As illustrated inFIG. 12, first of all, the UE10receives a signal such as a discovery signal, PSBCH, PBCH or PDCCH from the eNB30or the RSU50(step S102) to attempt to discover the eNB30or the RSU50(step S104). When the eNB30or the RSU50has been successfully discovered from the received signal (step S104/YES), the UE10determines whether the discovered eNB30or RSU50supports V2X communication with support by confirming support information included in the discovery signal or system information (step S106). When it is determined that the discovered eNB30or RSU50supports V2X communication with support (step S106/YES), the UE10switches to V2X communication with support (step S108). On the other hand, when discovery of the eNB30or RSU50from the received signal has failed (step S104/NO), the UE10continues V2X communication without support (step S110) and the processing returns to step S102again. Also, when it is determined that the discovered eNB30or RSU50does not support V2X communication with support (step S106/NO), the UE10continues V2X communication without support (step S110) and the processing returns to step S102again.

The basic operation of the UE10has been described. Next, operations of V2X communication with support will be described in detail. As V2X communication with support, three types, cooperative transmission, proxy transmission and Uu multiplex transmission, are considered.

The present communication method is a method through which a transmission device (e.g., UE10) and a supporting device (e.g., RSU50) cooperatively transmit messages to a reception device (e.g., UE20).

The present communication method may be regarded as an extension of coordinated multi-point transmission/reception (CoMP) technology in which base stations cooperatively transmit messages in LTE through V2X communication. A first difference between CoMP in LTE and the present communication method is that base stations cooperate or the UE10and the supporting device cooperate. A second difference from LTE is that, in V2X communication, a transmission device performs repetitive transmission multiple times for each message in order to improve message arrival probability. Accordingly, the supporting device acquires a message to be cooperatively transmitted in the initial period of repetitive transmission of the transmission device and transmits the acquired message in the remaining period of repetitive transmission.

The supporting device according to the present embodiment transmits a message, transmitted from the transmission device to the reception device using V2X communication, to the reception device in cooperation with the transmission device. In addition, the transmission device according to the present embodiment transmits control information (cooperative transmission parameters which will be described below) for causing the reception device to synthesize a message transmitted by the supporting device using V2X communication and a message transmitted by the transmission device using V2X communication to the reception device or the supporting device. Furthermore, the reception device according to the present embodiment synthesizes the message transmitted by the transmission device using V2X communication and the message transmitted from the supporting device that transmits messages in cooperation with the transmission device on the basis of the received control information. In this way, received messages may be synthesized in the reception device and thus reception quality (e.g., a signal-to-interference-plus-noise ratio (SINR)) is enhanced and message arrival probability is improved.

The present communication method will be described in detail with reference toFIGS. 13 and 14.

FIG. 13is an explanatory diagram of an overview of cooperative transmission according to the present embodiment. As illustrated inFIG. 13, the UE10transmits a message to the UE20mounted in a moving object22. The UE10performs repetitive transmission multiple times for each message. Since a recipient is the UE20, the UE10transmits a message using a PC5 interface. Accordingly, this message may be received by the RSU50having the PC5 interface, as illustrated inFIG. 13. The RSU50relays the received message to the UE20corresponding to the recipient. The UE20synthesizes the direct message received from the UE10and the relay message relayed by the RSU50. Accordingly, reception quality is enhanced and message arrival probability is improved.

FIG. 14is a timing diagram of cooperative transmission according to the present embodiment. In the figure, “Pedestrian Tx” indicates a message transmitted by the UE10. “RSU Tx/Rx” indicates a message transmitted or received by the RSU50. “Vehicle Rx” represents a message received by the UE20. As illustrated inFIG. 14, the UE10transmits a message with a redundancy version (RV) of 0. This message is received by each of the UE20and the RSU50, Subsequently, the RSU50transmits (i.e., relays) the received message to the UE20as it is. This message is received by the UE20. Additionally, the UE20synthesizes the received messages. InFIG. 14, a message retransmitted (repeatedly transmitted) by the UE10is omitted. For example, timing of relay by the RSU50may be identical to timing of retransmission by the UE10.

There may be a plurality of types of cooperative transmission. Examples include relay type without change, relay type with change, interface-changing relay type and the like. These types will be described in detail.

(1) Relay Type without Change

For example, a supporting device may relay a received message without changing the RV of the received message.

(1.1) Independent Relay Type

A supporting device may transmit a message independently of a transmission device. In this case, a reception device performs a reception operation in two resources, that is, a resource for reception from the transmission device and a resource for reception from the supporting device. An overview of cooperative transmission with respect to the independent relay type will be described with reference toFIG. 15.

FIG. 15is a timing diagram of independent relay type cooperative transmission according to the present embodiment. In the figure, “Pedestrian Tx” denotes a message transmitted by the UE10. “RSU Tx/Rx” denotes a message transmitted or received by the RSU50. “Vehicle Rx” represents a message received by the UE20. As illustrated inFIG. 15, the UE10transmits a message with an RV of 0 and a physical sidelink control channel (PSCCH). The message and the PSCCH are received by each of the UE20and the RSU50. Subsequently, the RSU50relays the message to the UE20without changing the RV on the basis of the received PSCCH. Here, the RSU50also transmits the PSCCH to the UE20. The message and PSCCH are received by the UE20. Additionally, the UE20synthesizes the received respective messages with reference to the received respective PSCCHs. AlthoughFIG. 15shows that the PSCCH and data signal are transmitted and received in different time resources, the PSCCH and data signal may be transmitted and received in the same or overlapping time resources. This is the same in other timing diagrams. Furthermore, inFIG. 15, a message retransmitted (i.e., repeatedly transmitted) by the UE10is omitted. For example, timing of relay by the RSU50may be identical to timing of retransmission by the UE10.

As illustrated inFIG. 15, the UE10notifies the UE20and the RSU50of the PSCCH. The PSCCH includes parameters (i.e., control information) regarding cooperative transmission. The RSU50relays the message to the UE20on the basis of the parameters received from the UE10. Further, the RSU50notifies the UE20of the PSCCH including the parameters regarding cooperative transmission. The UE20synthesizes messages on the basis of the parameters. The parameters regarding cooperative transmission are referred to as cooperative transmission parameters hereinafter. The cooperative transmission parameters notified of by the UE10and the cooperative transmission parameters notified of by the RSU50may be identical or different. An example of information that may be included in the cooperative transmission parameters notified of by the UE10will be described.

Cooperative Transmission Parameters Notified of by Transmission Device

For example, the cooperative transmission parameters may include a CoMP indicator indicating whether cooperation between a transmission device and a supporting device is implemented (i.e., whether the implementation is required). Accordingly, the reception device and the supporting device may be notified of whether cooperative transmission is performed.

In addition, the cooperative parameters may include a CoMP type that indicates the type of cooperation between the transmission device and the supporting device. In addition to the relay type without change, the relay type with change and the interface-changing relay type, the cooperative transmission type may be the number of supporting devices involved in cooperative transmission, a synthesis method in a reception device or the like.

Furthermore, the cooperative transmission parameters may include a transmission device ID that indicates identification information of the transmission device. Moreover, the cooperative transmission parameters may include a reception device ID that indicates identification information of the reception device. The cooperative transmission parameters may include a reception device group ID in addition to or instead of the reception device ID.

In addition, the cooperative transmission parameters may include RV information (RV value and/or RV pattern) of a target message of cooperative transmission.

The cooperative transmission parameters may include the number of repetitive transmissions of the target message of cooperative transmission. Accordingly, the supporting device may determine whether support of V2X communication is possible. For example, if the number of repetitive transmissions does not reach a maximum value, it may be determined that the supporting device may perform relay at a remaining repetitive transmission timing of the transmission device.

In addition, the cooperative transmission parameters may include a message ID or a packet ID that indicates identification information of the target message of cooperative transmission.

Furthermore, the cooperative transmission parameters may include modulation and coding scheme (MCS) information.

The cooperative transmission parameters may include timing advance (TA) information. The RSU50may appropriately control relay timing with reference to the TA information.

The cooperative transmission parameters may include frequency hopping indicator information. The supporting device may appropriately control frequency resources used for relay with reference to the frequency hopping indicator.

The cooperative transmission parameters notified of by the transmission device have been described. The supporting device sets radio resources used for transmission of messages on the basis of the cooperative transmission parameters. The supporting device may control radio resources used for relaying messages by itself, and thus may appropriately set radio resources, for example, depending on the communication state thereof. Next, the cooperative transmission parameters notified of by the supporting device will be described.

Cooperative Transmission Parameters Notified of by Supporting Device

The cooperative transmission parameters may include information indicating that a message transmitted by the supporting device is a relay of a message received from the transmission device. The reception device may synthesize messages on the basis of this information. Furthermore, the cooperative transmission parameters notified of by the supporting device may include the same information as the aforementioned cooperative transmission parameters notified of by the transmission device. For example, when a PSCCH includes a message ID or a packet ID in the cooperative transmission parameters notified of by the supporting device, the reception device may synthesize messages to which the same message ID or packet ID is attached, respectively received from the transmission device and the supporting device.

Examples of the cooperative transmission parameters have been described. The cooperative transmission parameters may be included in a PSCCH and notified of. Further, the cooperative transmission parameters may be distributed to a PSCCH and a physical sidelink shared channel (PSSCH) and included therein. For example, cooperative transmission parameters other than the cooperative transmission indicator may be included in the PSSCH, and the cooperative transmission indicator and information indicating a region on the PSSCH in which other cooperative transmission parameters are included may be included in the PSCCH.

(1.2) Controlled Relay Type

The supporting device may transmit a message on the basis of control by the transmission device. In this case, information indicating radio resources intended to be used by the supporting device for relaying is included in cooperative transmission parameters of which the supporting device is notified by the transmission device. Accordingly, the reception device may receive a message from the transmission device and a message from the supporting device in the same resources according to the cooperative transmission parameters. An overview of cooperative transmission of the controlled relay type will be described with reference toFIG. 16.

FIG. 16is a timing diagram of cooperative transmission of the controlled relay type according to the present embodiment. In the figure, “Pedestrian Tx” denotes a message transmitted by the UE10. “RSU Tx/Rx” denotes a message transmitted or received by the RSU50. “Vehicle Rx” represents a message received by the UE20. As illustrated inFIG. 16, the UE10transmits a message with an RV of 0 and a PSCCH. The message and PSCCH are received by each of the UE20and the RSU50. Then, the RSU50relays the message to the UE20without changing the RV on the basis of cooperative transmission parameters included in the received PSCCH. Additionally, the UE20synthesizes the respective messages with reference to the PSCCH received from the UE10. InFIG. 16, a message retransmitted (i.e., repeatedly transmitted) by the UE10is omitted. For example, timing of relay by the RSU50may be the same as timing of retransmission by the UE10.

Cooperative transmission parameters notified of by the transmission device will be described. Cooperative transmission parameters in cooperative transmission of this type may include the same information as the aforementioned independent relay type. Accordingly, an example of information that may be further included in the cooperative transmission parameters in cooperative transmission of this type will be described.

For example, the cooperative transmission parameters may include information that indicates radio resources intended to be used for transmission to the reception device. Specifically, the cooperative transmission parameters may include resource pool information for relay. Further, the cooperative transmission parameters may include resource pattern of transmission (RPT) information for relay. Here, it is desirable that RPT for relay have delayed time compared to normal RPT. In addition, the cooperative transmission parameters may include frequency band information for relay. The supporting device may use radio resources designated by the transmission device to relay a message with reference to such information. Accordingly, the reception device may receive the message from the transmission device and the message from the supporting device in the same resources.

The cooperative transmission parameters have been described. The cooperative transmission parameters may be included in a PSCCH and notified of or distributed to a PSCCH and a PSSCH and included therein.

(2) Relay Type with Change

For example, the supporting device may change the RV of a message transmitted from the transmission device and relay the message to the reception device.

Specifically, the supporting device may randomly change the RV and relay the message. In addition, the supporting device may change the RV on the basis of cooperative transmission parameters and relay the message. In this case, the supporting device may assign the same RV as the transmission device to a message transmitted at the same timing as transmission by the transmission device. An overview of cooperative transmission of the relay type with change will be described with reference toFIGS. 17 and 18.

FIGS. 17 and 18are timing diagrams of cooperative transmission of the relay type with change according to the present embodiment.FIG. 17shows a case in which the RSU50succeeds in the first reception andFIG. 18shows a case in which the RSU50fails in the first reception and succeeds in the second reception. In the figure, “Pedestrian Tx” denotes a message transmitted by the UE10. “RSU Tx/Rx” denotes a message transmitted or received by the RSU50. “Vehicle Rx” represents a message received by the UE20.

As illustrated inFIG. 17, the UE10transmits a message with an RV of 0 and a PSCCH. The message and the PSCCH are received by each of the UE20and the RSU50. Then, the UE10retransmits (i.e., repeatedly transmits) a message with an RV of 2. On the other hand, the RSU50changes the RV and relays the message to the UE20on the basis of cooperative transmission parameters included in the received PSCCH. Here, the RSU50changes the RV to 2 like the message retransmitted by the UE10and relays the message in the same resources (e.g., time and frequency) as those of retransmission by the RU10. Accordingly, the UE20may receive messages with the same RV in the same resources from the UE10and the RSU50. Additionally, the UE20synthesizes the message with the RV of 2 and the previously received message with the RV of 0 with reference to the PSCCH received from the UE10.

As illustrated inFIG. 18, the UE10transmits a message with an RV of 0 and a PSCCH. The message and the PSCCH are received by each of the UE20and the RSU50. Thereafter, the UE10retransmits (i.e., repeatedly transmits) a message with an RV of 2 and then a message with an RV of 1. On the other hand, the RSU50fails to decode the message with the RV of 0 alone and successfully decodes the message by synthesizing the message with the message with the RV of 2. In this case, the RSU50changes the RV of the message acquired through synthesis and relays the message to the UE20. Here, the RSU50changes the RV to 1 like the message subsequently retransmitted by the UE10and relays the message in the same resources (e.g., time and frequency) as those of retransmission by the UE10. Accordingly, the UE20may receive messages having the same RV from the UE10and the RSU50in the same resources. Additionally, the UE20synthesizes the messages with the RVs of 0, 1 and 2 with reference to the PSCCH received from the UE10.

The supporting device may relay a message transmitted from the transmission device through a PC5 interface to the reception device through the PC5 interface. Further, the supporting device may relay a message transmitted from the transmission device through the PC5 interface to the reception device through a Uu interface. In the latter case, the supporting device may be an eNB type RSU50. Furthermore, in the latter case, relay of a message from the RSU50to the eNB30and then transmission of the message from the eNB30to the reception device through the Uu interface may be considered, for example.

For example, the supporting device may change an interface and relay a message on the basis of cooperative transmission parameters included in a PSCCH notified of by the transmission device. An example of information that may be included in cooperative transmission parameters in cooperative transmission of this type will be described.

For example, the cooperative transmission parameters may include a cooperative transmission indicator, a cooperative transmission type, a transmission device ID, a reception device ID (and/or a reception device group ID), RV information (RV value and/or RV pattern), the number of repetitive transmissions and/or a message ID or a packet ID. Furthermore, the cooperative transmission messages may include information indicating a relay period (i.e. transmission period) that represents a period in which relay (i.e., transmission) will be performed. The information indicating the relay period is included in the cooperative transmission parameters and thus relay may be performed within the period.

(4) Other Relay Types

For example, a plurality of supporting devices may be involved in cooperative transmission. Cooperative transmission in which a plurality of supporting devices are involved will be described with reference toFIGS. 19 to 22.

FIGS. 19 and 20are explanatory diagrams of examples in which two supporting devices cooperatively transmit messages to a reception device.

As illustrated inFIG. 19, a message transmitted by the UE10through a PC5 interface is received by an RSU50A (eNB type) and an RSU50B other than the UE20. Then, the RSU50A and the RSU50B relay the received messages to the UE20. During relay, the RSU50A may use a Uu interface.

InFIG. 20, “Pedestrian Tx” denotes a message transmitted by the UE10. “RSU Tx/Rx” denotes a message transmitted or received by the RSU50B. “eNB Tx/Rx” represents a message transmitted or received by the RSU50A. “Vehicle Rx” represents a message received by the UE20. As illustrated inFIG. 20, the UE10transmits a message with an RV of 0. This message is received by each of the UE20, the RSU50A and the RSU50B. Then, the RSUs50A and50B transmit (i.e., relay) the received messages to the UE20. These messages are received by the UE20. The UE20synthesizes the received messages. InFIG. 20, a message retransmitted (i.e. repetitively transmitted) by the UE10is omitted. For example, timing of relay by the RSUs50A and50B may be identical to timing of retransmission by the UE10.

FIGS. 21 and 22are explanatory diagrams of examples in which a message is relayed between supporting devices.

In the example illustrated inFIG. 21, a message transmitted by the UE10through a PC5 interface is received by the RSU50A (eNB type) in addition to the UE20. Then, the RSU50A relays the received message to the RSU50B. In this case, the RSU50A corresponds to a relay device and the RSU50B relays the message received from the RSU50A to the UE20.

In the example illustrated inFIG. 22, a message transmitted by the UE10through a PC5 interface is received by the RSU50B in addition to the UE20. Then, the RSU50B relays the received message to the RSU50A (eNB type). In this case, the RSU50B corresponds to a relay device and the RSU50A relays the message received from the RSU50B to the UE20. A Uu interface may be used for relay by the RSU50A. In addition, an eNB30may perform relay instead of the RSU50A.

Cooperative transmission in which a plurality of supporting devices are involved has been described. Even when a plurality of supporting devices are involved, the technical features of cases in which one supporting device is involved, described above in detail, are equally applicable. For example, a plurality of involved supporting devices may perform relay independently from the transmission device or perform relay under the control of the transmission device.

(5) Modification Examples

While examples in which the UE10cooperates with the eNB30or the RSU50have been described, the present technology is not limited to these examples. For example, RSUs50may cooperate with each other. Such a case will be described in detail with reference toFIG. 23.

FIG. 23is an explanatory diagram of another example of cooperative transmission according to the present embodiment. As illustrated inFIG. 23, an RSU50A and an RSU50B cooperatively transmit messages to the UE10or the UE20. In this case, one of the RSU50A and the RSU50B is a transmission device and the other is a supporting device. In addition, the UE10or the UE20is a reception device. When the UE10is the reception device, the messages are called I2P messages. When the UE20is the reception device, the messages are called I2V messages.

The RSU50A and the RSU50B may perform I2I communication wirelessly or by wire. An interface in a wireless case is called a PC5 interface and an interface in a wired case is called an X2 interface. In addition, the eNB30may perform communication through a Uu interface or an X2 interface between the RSU50A and the RSU50B and controls the RSU50A and the RSU50B, for example.

The transmission device may notify the supporting device of cooperative transmission parameters using a PC5 interface or an X2 interface between RSUs50. Furthermore, the transmission device may notify the supporting device of the cooperative transmission parameters using a Uu interface or an X2 interface with the eNB30, that is, via the eNB30. In addition, the eNB30may set the cooperative transmission parameters and the transmission device and the supporting device may be notified of the cooperative transmission parameters through the Uu interface or the X2 interface.

The cooperative transmission parameters according to the present modification example may include the same information as the aforementioned information. Of course, the cooperative transmission parameters according to the present embodiment may include various types of information in addition to or instead of the aforementioned information. An example of information that may be included in the cooperative transmission parameters according to the present modification example will be described.

For example, the cooperative transmission parameters may include resource information indicating radio resources intended to be used for cooperative transmission.

In addition, the cooperative transmission parameters may include timing information indicating timing at which cooperative transmission is performed.

Furthermore, the cooperative transmission parameters may include target UE information indicating a reception device (e.g., the UE10or the UE20) that is a target of cooperative transmission.

Moreover, the cooperative transmission parameters may include data that is a target of cooperative transmission or information indicating the data that is a target of cooperative transmission.

The cooperative transmission parameters according to the present embodiment have been described. The supporting device performs cooperative transmission of messages on the basis of these cooperative transmission parameters.

Examples of processing flows related to cooperative transmission will be described with reference toFIGS. 24 to 26.

FIG. 24is a flowchart illustrating an example of a cooperative transmission processing flow executed by a transmission device (e.g., UE10) according to the present embodiment. As illustrated inFIG. 24, the UE10selects a cooperative transmission type (step S202). Cooperative transmission types include the aforementioned relay type without change, relay type with change, interface-changing relay type and the like, for example. The UE10selects any one of such cooperative transmission types. Then, the UE10transmits a PSCCH and a PSSCH including cooperative transmission parameters using a PC5 interface (steps S204and S206).

FIG. 25is a flowchart illustrating an example of a cooperative transmission processing flow executed by a supporting device (e.g., RSU50) according to the present embodiment. As illustrated inFIG. 25, first of all, the RSU50decodes a PSCCH received from a transmission device (e.g., UE10) (step S302). Then, the RSU50determines whether a cooperative transmission indicator is valid (step S304). When it is determined that the cooperative transmission indicator is not valid (step S304/NO), the processing is ended. On the other hand, when it is determined that the cooperative transmission indicator is valid (step S304/YES), the RSU50checks the cooperative transmission type (step S306). Next, the RSU50decodes a PSSCH received from the transmission device (step S308). Additionally, the RSU50relays a decoded message to the UE20depending on the cooperative transmission type (step S310). For example, when the cooperative transmission type is the relay type without change, the RSU50transmits the message through a PC5 interface according to cooperative transmission parameters notified of through the PSCCH. For example, if the cooperative transmission type is the relay type with change, the RSU50changes the RV and transmits the message through the PC5 interface according to the cooperative transmission parameters notified of through the PSCCH. For example, if the cooperative transmission type is the interface-changing relay type, the RSU50transmits the message through a Uu interface according to the cooperative transmission parameters notified of through the PSCCH.

FIG. 26is a flowchart illustrating an example of a reception processing flow executed by a reception device (e.g., UE20) according to the present embodiment. As illustrated inFIG. 26, first of all, the UE20decodes a PSCCH received from a transmission device (e.g., UE10) (step S402). Then, the UE20determines whether a cooperative transmission indicator is valid (step S404). When it is determined that the cooperative transmission indicator is not valid (step S404/NO), the UE20decodes a PSSCH received from the transmission device (step S406). On the other hand, when it is determined that the cooperative transmission indicator is valid (step S404/YES), the UE20checks the cooperative transmission type (step S408). Next, the UE20decodes the PSSCH received from the transmission device (step S410) and decodes a PSSCH received from a supporting device (e.g., RSU50) (step S412). Additionally, the UE20synthesizes packets obtained by decoding the respective PSSCHs (step S414).

This communication method is a method through which a supporting device (e.g., RSU50) transmits a message to a reception device (e.g., UE20) on behalf of a transmission device (e.g., UE10).

The supporting device according to the present embodiment transmits a message, transmitted from the transmission device to the reception device using V2X communication, to the reception device on behalf of the transmission device. In addition, the transmission device according to the present embodiment transmits control information (proxy transmission parameters which will be described below) for causing the supporting device to transmit a message using V2X communication on behalf of the transmission device to the reception device or the supporting device. Furthermore, the reception device according to the present embodiment receives the message transmitted by the supporting device on behalf of the transmission device using V2X communication. In this way, proxy transmission using sufficient power of the supporting device is realized, and thus reception quality of enhanced and message arrival probability is improved. Furthermore, the transmission device may reduce the number of repetitive transmissions according to proxy transmission of the supporting device, and thus power consumption may be reduced.

For example, the transmission device may notify the supporting device of parameters (i.e., control information) for proxy transmission. The supporting device relays a message to the reception device on the basis of the parameters received from the transmission device. Such parameters may be referred to as proxy transmission parameters hereinafter. An example of information included in the proxy transmission parameters will be described.

Proxy Transmission Parameters

For example, the proxy transmission parameters may include a proxy transmission indicator indicating whether the supporting device performs proxy transmission (i.e. requests the performance). Accordingly, the reception device and the supporting device may recognize whether proxy transmission is performed.

Furthermore, the proxy transmission parameters may include a transmission device ID indicating identification information of a transmission device. In addition, the proxy transmission parameters may include a reception device ID indicating identification information of a reception device. The proxy transmission parameters may include a reception device group ID in addition to or instead of the reception device ID.

Additionally, the proxy transmission parameters may include RV information (RV value and/or RV pattern) of a target message of proxy transmission.

The proxy transmission parameters may include the number of repetitive transmissions of the target message of proxy transmission. Accordingly, the supporting device may determine whether V2X communication can be supported. For example, if the number of repetitive transmissions does not reach a maximum value, it may be determined that proxy transmission by the supporting device can be performed at a remaining repetitive transmission timing of the transmission device.

Furthermore, the proxy transmission parameters may include a message ID or a packet ID that indicates identification information of the target message of proxy transmission.

In addition, the proxy transmission parameters may include MCS information.

The proxy transmission parameters may include TA information. The supporting device may control relay timing when possible with reference to the TA information.

Moreover, the proxy transmission parameters may include frequency hopping indicator information. The supporting device may appropriately control frequency resources used for relay with reference to the frequency hopping indicator.

The proxy transmission parameters may include information indicating a relay period that represents the time until relay (i.e., transmission) is performed.

The proxy transmission parameters have been described. The proxy transmission parameters may be included in a PSCCH and notified of. Further, the proxy transmission parameters may be distributed to a PSCCH and a PSSCH and included therein. For example, proxy transmission parameters other than the proxy transmission indicator may be included in the PSSCH and the proxy transmission indicator and information indicating a region on the PSSCH in which other proxy transmission parameters are included may be included in the PSCCH.

Reporting

The transmission device may stop repetitive transmission when the supporting device performs proxy transmission. For example, when the supporting device succeeds in reception of proxy transmission parameters and executes proxy transmission, the supporting device reports execution of proxy transmission to the transmission device. The transmission device stops repetitive transmission when the transmission device receives the report.

When proxy transmission is completed, that is, transmissions corresponding to a designated number of repetitive transmissions are completed, the supporting device may report completion of proxy transmission to the transmission device. In addition, when proxy transmission is not completed, the supporting device may report it to the transmission device.

Processing Flow

A processing flow related to proxy transmission will be described with reference toFIG. 27.

FIG. 27is a flowchart illustrating an example of a proxy transmission processing flow executed by a transmission device (e.g., UE10) according to the present embodiment. As illustrated inFIG. 27, first of all, the UE10transmits a message in a proxy transmission mode (step S502). Here, the UE10may transmit a PSCCH including proxy transmission parameters along with the message. Then, the UE10determines whether a report indicating that proxy transmission is performed has been received from the RSU50(step S504). When it is determined that the report has not been received (step S504/NO), the UE10continues repetitive transmission of messages (step S506). On the other hand, when it is determined that the report has been received (step S504/YES), the UE10stops repetitive transmission of messages (step S508).

This communication method is a method through which a transmission device (e.g., UE10) transmits V2X traffic intended to be transmitted to a reception device (e.g., UE20) through V2X communication, using a Uu interface instead of a PC5 interface to receive support of a supporting device (e.g., eNB30).

The transmission device according to the present embodiment multiplexes traffic transmitted using V2X communication (referred to hereinafter as V2X traffic) into traffic transmitted through the Uu interface (referred to hereinafter as Uu traffic) and transmits the Uu traffic to the supporting device through the Uu interface. In addition, the transmission device transmits control information (Uu multiplex transmission parameters) related to multiplexing through the Uu interface to the supporting device. The supporting device according to the present embodiment transmits V2X traffic, received through the Uu interface and to be transmitted from the transmission device to the reception device using V2X communication, to the reception device in cooperation with the transmission device or on behalf of the transmission device. The reception device according to the present embodiment receives the V2X traffic transmitted from the supporting device in cooperation with the transmission device or on behalf of the transmission device. In this way, cooperative transmission or proxy transmission is realized using sufficient power of the supporting device, and thus reception quality is enhanced and message arrival probability is improved. Furthermore, the transmission device may decrease the number of repetitive transmissions according to cooperative transmission or proxy communication by the supporting device, and thus power consumption may be reduced. In addition, the transmission device may decrease power consumption more than in a case in which a PC interface is used when a cell is small by using the Uu interface instead of the PC interface.

For example, the transmission device may notify the supporting device of parameters (i.e., control information) for Uu multiplex communication. The supporting device relays multiplexed V2X traffic to the reception device on the basis of the parameters received from the transmission device. Such parameters may be referred to hereinafter as multiplex transmission parameters. An example of information included in the Uu multiplex transmission parameters will be described.

Uu Multiplex Transmission Parameters

For example, the Uu multiplex transmission parameters may include a Uu multiplex transmission indicator indicating whether the transmission device transmits V2X traffic through the Uu interface. Accordingly, the reception device and the supporting device may recognize whether Uu multiplex transmission is performed.

In addition, the Uu multiplex transmission parameters may include Uu multiplex region information indicating a region (e.g., frequency resources or time resources) to which V2X traffic is multiplexed in a signal transmitted using the Uu interface. Accordingly, the supporting device may appropriately acquire V2X traffic.

Furthermore, the Uu multiplex transmission parameters may include a Uu multiplex transmission validity period indicating a period in which multiplex transmission is performed via the Uu interface.

The Uu multiplex transmission parameters may include identification information of the transmission device. The identification information of the transmission device may be location information of the transmission device, a lane ID, an area ID or the like, for example.

In addition, the Uu multiplex transmission parameters may include channel measurement information indicating a result of measurement by the transmission device.

The Uu multiplex transmission parameters may include a reception device ID indicating identification information of the reception device. The Uu multiplex transmission parameters may include a reception device group ID in addition to or instead of the reception device ID.

Further, the Uu multiplex transmission parameters may include RV information (RV value and/or RV pattern) of a target message of Uu multiplex transmission.

In addition, the Uu multiplex transmission parameters may include the number of repetitive transmissions of the target message of Uu multiplex transmission. Accordingly, the supporting device may determine whether V2X communication can be supported. For example, if the number of repetitive transmission does not reach a maximum value, it may be possible to determine whether Uu multiplex transmission by the supporting device can be performed at a remaining repetitive transmission timing of the transmission device.

Furthermore, the Uu multiplex transmission parameters may include a message ID or a packet ID that indicates identification information of the target message of Uu multiplex transmission.

In addition, the Uu multiplex transmission parameters may include information indicating a relay period (i.e., transmission period) that represents a period in which relay (i.e. transmission) is destined to be performed.

Examples of the Uu multiplex transmission parameters have been described. The Uu multiplex transmission parameters may be included in uplink control information (UCI) and notified of. Further, the Uu multiplex transmission parameters may be distributed to UCI and a physical uplink shared channel (PUSCH), for example, and included therein. For example, Uu multiplex transmission parameters other than the Uu multiplex transmission indicator and the Uu multiplex region information may be included in the PUSCH and the Uu multiplex transmission indicator and the Uu multiplex region information may be included in the UCI. In this case, the Uu multiplex region information indicates a region in which Uu multiplex transmission parameters other than the Uu multiplex transmission indicator and the Uu multiplex region information are included in addition to V2X traffic.

Reporting

When proxy transmission or cooperative transmission is completed, that is, transmissions corresponding to a designated number of repetitive transmissions are completed, the supporting device may report completion of proxy transmission or cooperative transmission to the transmission device. In addition, when proxy transmission or cooperative transmission is not completed, the supporting device may report it to the transmission device. Such reporting may be performed using downlink control information (DCI) or a physical hybrid-ARQ indicator channel (PHICH), for example.

Processing Flow

A processing flow related to Uu multiplex transmission will be described with reference toFIG. 28.

FIG. 28is a flowchart illustrating an example of a Uu multiplex transmission processing flow executed by a transmission device (e.g., UE10) according to the present embodiment. As illustrated inFIG. 28, first of all, V2X traffic is generated in the UE10(step S602). Then, the UE10determines whether there is Uu traffic (step S604). When it is determined that there is Uu traffic (step S604/YES), the UE10determines whether a period from scheduling request transmission to scheduling grant reception through the Uu interface is within a V2X message period (step S606). When it is determined that the period is within the V2X message period (step S606/YES), the UE10performs Uu multiplex transmission of multiplexing V2X traffic and Uu traffic and transmitting the multiplexed V2X traffic and Uu traffic through the Uu interface (step S608). On the other hand, when it is determined that there is no Uu traffic (step S604/NO) or when it is determined that the period is not within the V2X message time period (step S606/NO), the UE10transmits the V2X traffic through the PC5 interface (step S610).

4. APPLICATION EXAMPLES

The technology of the present disclosure is applicable to various products. For example, the eNB30may be realized as any type of evolved Node B (eNB) such as a macro eNB, and a small eNB. A small eNB may be an eNB that covers a cell smaller than a macro cell, such as a pico eNB, micro eNB, or home (femto) eNB. Instead, the eNB may be realized as any other types of base stations such as a NodeB and a base transceiver station (BTS). The eNB may include a main body (that is also referred to as a base station device) configured to control wireless communication, and one or more remote radio heads (RRH) disposed in a different place from the main body. Additionally, various types of terminals to be discussed later may also operate as the eNB by temporarily or semi-permanently executing a base station function. Furthermore, at least part of components of the eNB30may be realized in a base station device or a module for the base station device.

For example, the UEs10and20, or the RUS50may be realized as a mobile terminal such as a smartphone, a tablet personal computer (PC), a notebook PC, a portable game terminal, a portable/dongle type mobile router, and a digital camera, or an in-vehicle terminal such as a car navigation device. The UEs10and20, or the RUS50may also be realized as a terminal (that is also referred to as a machine type communication (MTC) terminal) that performs machine-to-machine (M2M) communication. Furthermore, the at least some of these structural elements of the UEs10and20, or the RSU50may be realized in a module (such as an integrated circuit module including a single die) mounted on each of the terminals.

<4-1. Application Examples Regarding eNB>

First Application Example

FIG. 29is a block diagram illustrating a first example of a schematic configuration of an eNB to which the technology of the present disclosure may be applied. An eNB800includes one or more antennas810and a base station device820. Each antenna810and the base station device820may be connected to each other via an RF cable.

Each of the antennas810includes a single or multiple antenna elements (such as multiple antenna elements included in an MIMO antenna), and is used for the base station device820to transmit and receive radio signals. The eNB800may include the multiple antennas810, as illustrated inFIG. 29. For example, the multiple antennas810may be compatible with multiple frequency bands used by the eNB800. AlthoughFIG. 29illustrates the example in which the eNB800includes the multiple antennas810, the eNB800may also include a single antenna810.

The base station device820includes a controller821, a memory822, a network interface823, and a wireless communication interface825.

The controller821may be, for example, a CPU or a DSP, and operates various functions of a higher layer of the base station device820. For example, the controller821generates a data packet from data in signals processed by the wireless communication interface825, and transfers the generated packet via the network interface823. The controller821may bundle data from multiple base band processors to generate the bundled packet, and transfer the generated bundled packet. The controller821may have logical functions of performing control such as radio resource control, radio bearer control, mobility management, admission control, and scheduling. The control may be performed in corporation with an eNB or a core network node in the vicinity. The memory822includes RAM and ROM, and stores a program that is executed by the controller821, and various types of control data (such as a terminal list, transmission power data, and scheduling data).

The network interface823is a communication interface for connecting the base station device820to a core network824. The controller821may communicate with a core network node or another eNB via the network interface823. In that case, the eNB800, and the core network node or the other eNB may be connected to each other through a logical interface (such as an S1 interface and an X2 interface). The network interface823may also be a wired communication interface or a wireless communication interface for radio backhaul. If the network interface823is a wireless communication interface, the network interface823may use a higher frequency band for wireless communication than a frequency band used by the wireless communication interface825.

The wireless communication interface825supports any cellular communication scheme such as Long Term Evolution (LTE) and LTE-Advanced, and provides wireless connection to a terminal positioned in a cell of the eNB800via the antenna810. The wireless communication interface825may typically include, for example, a baseband (BB) processor826and an RF circuit827. The BB processor826may perform, for example, encoding/decoding, modulating/demodulating, and multiplexing/demultiplexing, and performs various types of signal processing of layers (such as L1, medium access control (MAC), radio link control (RLC), and a packet data convergence protocol (PDCP)). The BB processor826may have a part or all of the above-described logical functions instead of the controller821. The BB processor826may be a memory that stores a communication control program, or a module that includes a processor and a related circuit configured to execute the program. Updating the program may allow the functions of the BB processor826to be changed. The module may be a card or a blade that is inserted into a slot of the base station device820. Alternatively, the module may also be a chip that is mounted on the card or the blade. Meanwhile, the RF circuit827may include, for example, a mixer, a filter, and an amplifier, and transmits and receives radio signals via the antenna810.

The wireless communication interface825may include the multiple BB processors826, as illustrated inFIG. 29. For example, the multiple BB processors826may be compatible with multiple frequency bands used by the eNB800. The wireless communication interface825may include the multiple RF circuits827, as illustrated inFIG. 29. For example, the multiple RF circuits827may be compatible with multiple antenna elements. AlthoughFIG. 29illustrates the example in which the wireless communication interface825includes the multiple BB processors826and the multiple RF circuits827, the wireless communication interface825may also include a single BB processor826or a single RF circuit827.

In the eNB800illustrated inFIG. 29, the processing unit350described with reference toFIG. 10may be mounted in the wireless communication interface825(e.g., BB processor826) or controller821. Furthermore, the wireless communication unit320may be mounted in the wireless communication interface825(e.g., RF circuit827). The antenna part310may be mounted in the antenna810. The network communication unit330may be mounted in the controller821and/or the network interface823. In addition, the storage unit340may be mounted in the memory822.

Second Application Example

FIG. 30is a block diagram illustrating a second example of a schematic configuration of an eNB to which the technology of the present disclosure may be applied. An eNB830includes one or more antennas840, a base station device850, and an RRH860. Each antenna840and the RRH860may be connected to each other via an RF cable. The base station device850and the RRH860may be connected to each other via a high speed line such as an optical fiber cable.

Each of the antennas840includes a single or multiple antenna elements (such as multiple antenna elements included in an MIMO antenna), and is used for the RRH860to transmit and receive radio signals. The eNB830may include the multiple antennas840, as illustrated inFIG. 30. For example, the multiple antennas840may be compatible with multiple frequency bands used by the eNB830. AlthoughFIG. 30illustrates the example in which the eNB830includes the multiple antennas840, the eNB830may also include a single antenna840.

The wireless communication interface855supports any cellular communication scheme such as LTE and LTE-Advanced, and provides wireless communication to a terminal positioned in a sector corresponding to the RRH860via the RRH860and the antenna840. The wireless communication interface855may typically include, for example, a BB processor856. The BB processor856is the same as the BB processor826described with reference toFIG. 29, except the BB processor856is connected to the RF circuit864of the RRH860via the connection interface857. The wireless communication interface855may include the multiple BB processors856, as illustrated inFIG. 30. For example, the multiple BB processors856may be compatible with multiple frequency bands used by the eNB830. AlthoughFIG. 30illustrates the example in which the wireless communication interface855includes the multiple BB processors856, the wireless communication interface855may also include a single BB processor856.

The connection interface857is an interface for connecting the base station device850(wireless communication interface855) to the RRH860. The connection interface857may also be a communication module for communication in the above-described high speed line that connects the base station device850(wireless communication interface855) to the RRH860.

The RRH860includes a connection interface861and a wireless communication interface863.

The connection interface861is an interface for connecting the RRH860(wireless communication interface863) to the base station device850. The connection interface861may also be a communication module for communication in the above-described high speed line.

The wireless communication interface863transmits and receives radio signals via the antenna840. The wireless communication interface863may typically include, for example, the RF circuit864. The RF circuit864may include, for example, a mixer, a filter, and an amplifier, and transmits and receives radio signals via the antenna840. The wireless communication interface863may include multiple RF circuits864, as illustrated inFIG. 30. For example, the multiple RF circuits864may support multiple antenna elements. AlthoughFIG. 30illustrates the example in which the wireless communication interface863includes the multiple RF circuits864, the wireless communication interface863may also include a single RF circuit864.

The eNB830illustrated inFIG. 30, the processing unit350described with reference toFIG. 10may be mounted in the wireless communication interface855, a wireless communication interface863and/or the controller851. Furthermore, the wireless communication unit320may be mounted in the wireless communication interface863(e.g., RF circuit864). The antenna part310may be mounted in the antenna840. The network communication unit330may be mounted in the controller851and/or the network interface853. In addition, the storage unit340may be mounted in the memory852.

<4-2. Application Examples Regarding UE and RSU>

First Application Example

The processor901may be, for example, a CPU or a system on a chip (SoC), and controls functions of an application layer and another layer of the smartphone900. The memory902includes RAM and ROM, and stores a program that is executed by the processor901, and data. The storage903may include a storage medium such as a semiconductor memory and a hard disk. The external connection interface904is an interface for connecting an external device such as a memory card and a universal serial bus (USB) device to the smartphone900.

The camera906includes an image sensor such as a charge coupled device (CCD) and a complementary metal oxide semiconductor (CMOS), and generates a captured image. The sensor907may include a group of sensors such as a measurement sensor, a gyro sensor, a geomagnetic sensor, and an acceleration sensor. The microphone908converts sounds that are input to the smartphone900to audio signals. The input device909includes, for example, a touch sensor configured to detect touch onto a screen of the display device910, a keypad, a keyboard, a button, or a switch, and receives an operation or an information input from a user. The display device910includes a screen such as a liquid crystal display (LCD) and an organic light-emitting diode (OLED) display, and displays an output image of the smartphone900. The speaker911converts audio signals that are output from the smartphone900to sounds.

The wireless communication interface912supports any cellular communication scheme such as LTE and LTE-Advanced, and performs wireless communication. The wireless communication interface912may typically include, for example, a BB processor913and an RF circuit914. The BB processor913may perform, for example, encoding/decoding, modulating/demodulating, and multiplexing/demultiplexing, and performs various types of signal processing for wireless communication. Meanwhile, the RF circuit914may include, for example, a mixer, a filter, and an amplifier, and transmits and receives radio signals via the antenna916. The wireless communication interface912may also be a one chip module that has the BB processor913and the RF circuit914integrated thereon. The wireless communication interface912may include the multiple BB processors913and the multiple RF circuits914, as illustrated inFIG. 31. AlthoughFIG. 31illustrates the example in which the wireless communication interface912includes the multiple BB processors913and the multiple RF circuits914, the wireless communication interface912may also include a single BB processor913or a single RF circuit914.

Furthermore, in addition to a cellular communication scheme, the wireless communication interface912may support another type of wireless communication scheme such as a short-distance wireless communication scheme, a near field communication scheme, and a radio local area network (LAN) scheme. In that case, the wireless communication interface912may include the BB processor913and the RF circuit914for each wireless communication scheme.

Each of the antenna switches915switches connection destinations of the antennas916among multiple circuits (such as circuits for different wireless communication schemes) included in the wireless communication interface912.

Each of the antennas916includes a single or multiple antenna elements (such as multiple antenna elements included in an MIMO antenna), and is used for the wireless communication interface912to transmit and receive radio signals. The smartphone900may include the multiple antennas916, as illustrated inFIG. 31. AlthoughFIG. 31illustrates the example in which the smartphone900includes the multiple antennas916, the smartphone900may also include a single antenna916.

Furthermore, the smartphone900may include the antenna916for each wireless communication scheme. In that case, the antenna switches915may be omitted from the configuration of the smartphone900.

The bus917connects the processor901, the memory902, the storage903, the external connection interface904, the camera906, the sensor907, the microphone908, the input device909, the display device910, the speaker911, the wireless communication interface912, and the auxiliary controller919to each other. The battery918supplies power to blocks of the smartphone900illustrated inFIG. 31via feeder lines, which are partially shown as dashed lines in the figure. The auxiliary controller919operates a minimum necessary function of the smartphone900, for example, in a sleep mode.

In the smartphone900illustrated inFIG. 31, the processing unit150described with reference toFIG. 8, the processing unit250described with reference toFIG. 9or the processing unit540described with reference toFIG. 11may be mounted in the wireless communication interface912or the processor901. Furthermore, the wireless communication unit120, the wireless communication unit220or the wireless communication unit520may be mounted in the wireless communication interface912(e.g., RF circuit914). The GNSS signal processing unit130or the GNSS signal processing unit230may be mounted in the sensor907. The antenna part110, the antenna part210or the antenna part510may be mounted in the antenna916. In addition, the storage unit140, the storage unit240or the storage unit530may be mounted in the memory902.

Second Application Example

FIG. 32is a block diagram illustrating an example of a schematic configuration of a car navigation device920to which the technology of the present disclosure may be applied. The car navigation device920includes a processor921, a memory922, a global positioning system (GPS) module924, a sensor925, a data interface926, a content player927, a storage medium interface928, an input device929, a display device930, a speaker931, a wireless communication interface933, one or more antenna switches936, one or more antennas937, and a battery938.

The processor921may be, for example, a CPU or a SoC, and controls a navigation function and another function of the car navigation device920. The memory922includes RAM and ROM, and stores a program that is executed by the processor921, and data.

The GPS module924uses GPS signals received from a GPS satellite to measure a position (such as latitude, longitude, and altitude) of the car navigation device920. The sensor925may include a group of sensors such as a gyro sensor, a geomagnetic sensor, and a barometric sensor. The data interface926is connected to, for example, an in-vehicle network941via a terminal that is not shown, and acquires data generated by the vehicle, such as vehicle speed data.

The content player927reproduces content stored in a storage medium (such as a CD and a DVD) that is inserted into the storage medium interface928. The input device929includes, for example, a touch sensor configured to detect touch onto a screen of the display device930, a button, or a switch, and receives an operation or an information input from a user. The display device930includes a screen such as a LCD or an OLED display, and displays an image of the navigation function or content that is reproduced. The speaker931outputs sounds of the navigation function or the content that is reproduced.

The wireless communication interface933supports any cellular communication scheme such as LET and LTE-Advanced, and performs wireless communication. The wireless communication interface933may typically include, for example, a BB processor934and an RF circuit935. The BB processor934may perform, for example, encoding/decoding, modulating/demodulating, and multiplexing/demultiplexing, and performs various types of signal processing for wireless communication. Meanwhile, the RF circuit935may include, for example, a mixer, a filter, and an amplifier, and transmits and receives radio signals via the antenna937. The wireless communication interface933may be a one chip module having the BB processor934and the RF circuit935integrated thereon. The wireless communication interface933may include the multiple BB processors934and the multiple RF circuits935, as illustrated inFIG. 32. AlthoughFIG. 32illustrates the example in which the wireless communication interface933includes the multiple BB processors934and the multiple RF circuits935, the wireless communication interface933may also include a single BB processor934or a single RF circuit935.

Furthermore, in addition to a cellular communication scheme, the wireless communication interface933may support another type of wireless communication scheme such as a short-distance wireless communication scheme, a near field communication scheme, and a radio LAN scheme. In that case, the wireless communication interface933may include the BB processor934and the RF circuit935for each wireless communication scheme.

Each of the antenna switches936switches connection destinations of the antennas937among multiple circuits (such as circuits for different wireless communication schemes) included in the wireless communication interface933.

Each of the antennas937includes a single or multiple antenna elements (such as multiple antenna elements included in an MIMO antenna), and is used for the wireless communication interface933to transmit and receive radio signals. The car navigation device920may include the multiple antennas937, as illustrated inFIG. 32. AlthoughFIG. 32illustrates the example in which the car navigation device920includes the multiple antennas937, the car navigation device920may also include a single antenna937.

Furthermore, the car navigation device920may include the antenna937for each wireless communication scheme. In that case, the antenna switches936may be omitted from the configuration of the car navigation device920.

The battery938supplies power to blocks of the car navigation device920illustrated inFIG. 32via feeder lines that are partially shown as dashed lines in the figure. The battery938accumulates power supplied form the vehicle.

In the car navigation device920illustrated inFIG. 32, the processing unit150described with reference toFIG. 8, the processing unit250described with reference toFIG. 9or the processing unit540described with reference toFIG. 11may be mounted in the wireless communication interface933or the processor921. Furthermore, the wireless communication unit120, the wireless communication unit220or the wireless communication unit520may be mounted in the wireless communication interface933(e.g., RF circuit935). The GNSS signal processing unit130or the GNSS signal processing unit230may be mounted in the GPS module924. The antenna part110, the antenna part210or the antenna part510may be mounted in the antenna937. In addition, the storage unit140, the storage unit240or the storage unit530may be mounted in the memory922.

The technology of the present disclosure may also be realized as an in-vehicle system (or a vehicle)940including one or more blocks of the car navigation device920, the in-vehicle network941, and a vehicle module942. That is, the in-vehicle system (or a vehicle)940may be provided as the device including the processing unit250described with reference toFIG. 9. The vehicle module942generates vehicle data such as vehicle speed, engine speed, and trouble information, and outputs the generated data to the in-vehicle network941.

An embodiment of the present disclosure has been described in detail with reference toFIGS. 1 to 32. As described above, the supporting device transmits a message, transmitted from the transmission device to the reception device using V2X communication, to the reception device in cooperation with the transmission device. The supporting device supports V2X communication of the transmission device and thus message arrival probability may be improved, and the number of retransmissions by the transmission device is reduced, thus decreasing power consumption of the transmission device.

Processes described using flowcharts and sequence diagrams in the specification may not necessarily be performed in the illustrated orders. Some processing steps may be executed in parallel. Further, additional processing steps may be employed and some processing steps may be omitted.

In addition, a computer program for causing a processor (e.g., CPU, DSP or the like) included in a device (e.g., UE10, UE20, eNB30or RSU50, or a module for such devices) of the specification to function as a component (e.g., processing unit150, processing unit250, processing unit350, processing unit540or the like) of the device (in other words, a computer program for causing the processor to execute operations of a component of the device) may also be generated. Further, a recording medium in which the computer program is recorded may be provided. Moreover, a device including a memory that stores the computer program and one or more processors that can execute the computer program (e.g., a base station, a base station device or a module for the base station device, or a terminal device or a module for the terminal device) may also be provided. In addition, a method including operations of components of the device is included in the technology according to the present disclosure.

Further, the effects described in this specification are merely illustrative or exemplified effects, and are not limitative. That is, with or in the place of the above effects, the technology according to the present disclosure may achieve other effects that are clear to those skilled in the art based on the description of this specification.

An electronic device including:

circuitry configured to

receive a signal from at least one of a base station or road side unit (RSU);

determine whether the a least one of the base station or RSU support cooperative vehicle-to-X (V2X) communication; and

perform cooperative V2X communication with a vehicle-mounted electronic device with support from the at least one of the base station or RSU based on the determination.

The electronic device of (1), wherein the signal received from the at least one of a base station or RSU is a discovery signal including information indicating whether cooperative V2X communication is supported.

The electronic device of any of (1) to (2), wherein the signal received from the at least one of the base station or RSU includes information in a system information block (SIB) or master information block (MIB) indicating whether cooperative V2X communication is supported.

The electronic device of any of (1) to (3), wherein the circuitry is configured to perform cooperative V2X communication with the vehicle-mounted electronic device with support from the at least one of the base station or RSU when it is determined that the at least one of the base station or RSU support cooperative V2X communication.

The electronic device of (4), wherein the circuitry is configured to perform cooperative V2X communication with the vehicle-mounted electronic device with support from the at least one of the base station or RSU by transmitting a message directly to the vehicle-mounted electronic device and transmitting the message to the at least one of the base station or RSU.

The electronic device of (5), wherein the circuitry is configured to transmit the message directly to the vehicle-mounted electronic device using device-to-device (D2D) communication.

The electronic device of any of (5) to (6), wherein the circuitry is configured to transmit control information to the vehicle-mounted electronic device for synthesizing the message transmitted from the electronic and the message relayed by the at least one of the base station or RSU.

The electronic device of (7), wherein the circuitry is configured to transmit the control information to the vehicle-mounted electronic device using device-to-device (D2D) communication.

The electronic device of any of (7) to (8), wherein the control information includes a coordinated multi-point (CoMP) indicator indicating that cooperative V2X transmission between the electronic device and the at least one of the base station or RSU is implemented.

The electronic device of (9), wherein the control information includes a CoMP type indicator indicating a type of the cooperative V2X transmission implemented between the electronic device and the at least one of the base station or RSU.

The electronic device of any of (7) to (10), wherein the control information includes at least one of a transmission device identifier that identifies the electronic device, a reception device identifier that identifies the vehicle-mounted electronic device and a reception device group identifier identifying a group of devices including the vehicle-mounted electronic device.

The electronic device of any of (7) to (11), wherein the control information includes at least one of a redundancy version or redundancy pattern corresponding to the message.

The electronic device of any of (7) to (12), wherein the control information indicates a number of repetitive transmissions of the message.

The electronic device of any of (7) to (13), wherein the control information indicates at least one of a message identifier identifying the message, modulation and coding scheme (MCS) information, timing advance information or frequency hopping indicator information.

The electronic device of any of (5) to (14), wherein control information for the vehicle-mounted electronic device to synthesize the message transmitted from the electronic and the message relayed by the at least one of the base station or RSU is transmitted by the at least one of the base station or RSU.

The electronic device of any of (5) to (15), wherein control information for the vehicle-mounted electronic device to synthesize the message transmitted from the electronic and the message relayed by the at least one of the base station or RSU is provided in at least one of a physical sidelink control channel (PSCCH) or a physical sidelink shared channel (PSCCH).

The electronic device of any of (5) to (16), wherein the circuitry is configured to inform the at least one of the base station or RSU of transmission resources to be used by the base station or RSU to relay the message to the vehicle-mounted electronic device.

The electronic device of any of (5) to (15), wherein the circuitry is configured to inform the vehicle-mounted electronic device and the at least one of the base station or RSU of transmission resources to be used by the base station or RSU to relay the message to the vehicle-mounted electronic device via a physical sidelink control channel (PSCCH).

The electronic device of any of (5) to (15), wherein the circuitry is configured to retransmit the message by retransmitting the message with an updated redundancy version, and the at least one of the base station or RSU is configured to update the redundancy version of the message so that a redundancy version of the relayed message coincides with the redundancy version of the message transmitted by the electronic device in a same time and frequency resource.

The electronic device of any of (5) to (15), wherein the circuitry is configured to transmit the message to the at least one of the base station or RSU via a PC5 interface and the at least one of the base station or RSU relays the message to the vehicle-mounted electronic device via a Uu interface.

The electronic device of any of (7) to (20), wherein the control information includes a time period during which the cooperative V2X transmission between the electronic device and the at least one of the base station or RSU is implemented.

The electronic device of any of (1) to (4), wherein the circuitry is configured to perform the cooperative V2X communication with the vehicle-mounted electronic device with support from the at least one of the base station or RSU by transmitting a message intended for the vehicle-mounted electronic device to the at least one of the base station or RSU which functions as a proxy for transmitting the message from the electronic device to the vehicle-mounted electronic device.

The electronic device of any of (1) to (22), wherein the circuitry is configured to perform the cooperative V2X communication with the vehicle-mounted electronic device with support from the at least one of the base station or RSU by transmitting a message intended for the vehicle-mounted electronic device to the at least one of the base station or RSU which forwards the message to the electronic device.

The electronic device of (23), wherein the circuitry is configured to transmit the message to the at least one of the base station or RSU via a PC5 interface and the at least one of the base station or RSU forwards the message to the vehicle-mounted electronic device via a Uu interface.

The electronic device of (24), wherein the circuitry is configured to transmit control information to the at least one of the base station or RSU specifying parameters for forwarding the message via the Uu interface.

The electronic device of (25), wherein the parameters include at least one of Uu multiplex parameters, a Uu multiplex transmission validity period, identification information of the transmission device, channel measurement information, identification information of the vehicle-mounted electronic device, a redundancy version corresponding to the message, and a number of repetitive transmissions of the message.

A method performed by an electronic device, the method including:

receiving a signal from at least one of a base station or road side unit (RSU);

determining whether the a least one of the base station or RSU support cooperative vehicle-to-X (V2X) communication; and

performing V2X communication with a vehicle-mounted electronic device with support from the at least one of the base station or RSU based on the determination.

A system including:

a network device including first circuitry configured to

transmit a signal to a terminal device indicating whether the network device supports cooperative vehicle-to-X (V2X) transmission of messages from the terminal device to a vehicle-mounted terminal device;

receive, from the terminal device, a message intended for the vehicle-mounted terminal device; and

perform cooperative V2X communication with the vehicle-mounted terminal device by transmitting the message received from the terminal device to the vehicle-mounted terminal device.

The system of (28), further including:

the terminal device including second circuitry configured to receive the signal from the network device indicating whether the network device supports cooperative vehicle-to-X (V2X) transmission of messages from the terminal device to the vehicle-mounted terminal device;
determine whether the network device supports cooperative vehicle-to-X (V2X) communication; and
perform cooperative V2X communication with the vehicle-mounted electronic device with support from the network device based on the determination.

REFERENCE SIGNS LIST