The present invention relates to the field of wireless communications technologies, and in particular, to a method and a device for device-to-device communication.
An inevitable trend of a wireless cellular communications network in the future is towards a high rate, a large capacity, and higher QoS. How to effectively use a limited bandwidth resource to implement wireless broadband seems especially important. At present, a local service that rapidly develops in the mobile Internet, such as video/music sharing, urgently needs to be supported by introducing a new technology to an existing cellular network.
Conventional cellular mobile communications networks are controlled in a centralized manner; even if two user equipments are very adjacent, communication between the user equipment needs to be performed by using a base station and a core network. A centralized control system is convenient for resource management and interference control, but a disadvantage is increasingly obvious, that is, a resource utilization rate of the centralized control system is not very high in some scenarios. For example, even if two UEs are very adjacent, double resources are needed for communication, including air interface resources and base station backhaul resources.
In order to increase a utilization rate of an air interface spectrum, reduce a heavy load of a conventional cellular network, and obtain a higher system throughput, researches of device-to-device communication (Device-to-Device communication, D2D) in a cellular network draw ever-increasing attentions. Auser equipment can directly perform data communication with another user equipment in a direct manner or under control of a base station while continuously maintaining communication that is performed by using the base station, thereby reducing occupation of an air interface resource and increasing a system throughput, and also decreasing a communication delay, lowering an interference level, and saving energy of the user equipment.
A device-to-device communication technology is mostly applied in a local service, such as a multicast data service and a local file sharing service. In the multicast data service, a service provider, such as an organizer of a concert or another large-scale activity, needs to send data with same content to participants of a gathering; and the organizer can use the D2D communication technology to complete a service immediately and reliably. If local data (for example, a file, a photo, and a video) of a user needs to be shared between adjacent user equipment, D2D can also be used to establish a user equipment cluster to complete data sharing. In addition, services that the D2D can provide further include a cooperative multiplayer game in a mobile state, a mobile advertising service, a dating service, communication between vehicles, mobile relay, and the like.
Compared with a wireless local area network (Wireless Local Area Networks, WLAN) and Bluetooth that can support similar services and use an unauthorized frequency band, device-to-device communication in a cellular communications system is controlled by a base station and uses an authorized frequency band resource allocated by the base station, which can control a system interference level so as to obtain device-to-device communication with a high data rate, and can enjoy a mobile advantage brought by the cellular communications system. In addition, the D2D communication is transparent to a user equipment user, so that in the D2D communication, complex manual pairing and access point configuration do not need to be performed as those in the WLAN and Bluetooth, thereby improving user experience and facilitating promotion of a service.
A typical D2D scenario is shown in
From the perspective of standardization, the design of a D2D system is based on an existing standard protocol. Typically, the D2D system can be designed based on the 3GPP Long Term Evolution Advanced LTE/Long Term Evolution Advanced LTE-A (Rel-10/11/12 or a later version), which is a single standard and is applicable to a network supporting a high-level protocol.
On the other hand, with advancement of technologies, a base station supporting multiple mode networks has been developed in the industry. Under this kind of base station, wireless networks with multiple modes can cover in an overlapping manner, as shown in
User equipment technologies are also constantly developing. Emergence of multimode user equipment also enables a user equipment to hand over between networks with multiple modes. For a D2D technology, because the D2D technology is developed based on a specific access technology, communication can be performed only within network coverage of a corresponding technology. By using
Embodiments of the present invention provide a method and a device for device-to-device communication, so as to solve a problem in the prior art that: in a D2D scenario, an application range of D2D is limited because control signaling cannot be transferred to a user equipment in a heterogeneous network.
According to one aspect, a device-to-device communication method is provided, where the method includes:
receiving, by a base station, a device capability indication of a user equipment, where the device capability indication indicates a capability of heterogeneous device-to-device communication transmission is supported by the user equipment;
sending, by the base station, a base station capability indication to the user equipment, where the base station capability indication indicates a capability of heterogeneous device-to-device communication transmission is supported by the base station;
establishing, by the base station, a first transmission channel, where the first transmission channel is established in a network that is supported by the base station serving the user equipment, and is used to transmit device-to-device communication control information to the user equipment, where the device-to-device communication control information is control signaling for controlling the user equipment to perform data exchange with another user equipment; and
sending, by the base station, the device-to-device communication control information to the user equipment through the first transmission channel, so that the user equipment performs transmission of a device-to-device communication signal with the another user equipment according to the device-to-device communication control information, where the device-to-device communication signal is data exchanged between the user equipment and the another user equipment.
According to another aspect, a base station is provided, where the base station includes:
a first capability receiving unit, configured to receive a device capability indication of a user equipment, where the device capability indication indicates a capability of heterogeneous device-to-device communication transmission is supported by the user equipment;
a first capability sending unit, configured to send a base station capability indication to the user equipment, where the base station capability indication indicates a capability of heterogeneous device-to-device communication transmission is supported by the base station;
a channel establishing unit, configured to establish a first transmission channel, where the first transmission channel is established in a network that is supported by the base station serving the user equipment, and is used to transmit device-to-device communication control information to the user equipment, where the device-to-device communication control information is control signaling for controlling the user equipment to perform data exchange with another user equipment; and
a control information transmitting unit, configured to send the device-to-device communication control information to the user equipment through the first transmission channel, so that the user equipment performs transmission of a device-to-device communication signal with the another user equipment according to the device-to-device communication control information, where the device-to-device communication signal is data exchanged between the user equipment and the another user equipment.
According to still another aspect, a device-to-device communication method is provided, where the method includes:
receiving, by a user equipment, a base station capability indication transmitted by a base station, where the base station capability indication indicates a capability of heterogeneous device-to-device communication transmission is supported by the base station;
receiving, by the user equipment through a first transmission channel established by the base station, device-to-device communication control information sent by the base station, where the first transmission channel is established in a network that is supported by the base station serving the user equipment, and is used to transmit the device-to-device communication control information to the user equipment, where the device-to-device communication control information is control signaling for controlling the user equipment to perform data exchange with another user equipment; and
performing, by the user equipment, transmission of a device-to-device communication signal with the another user equipment according to the device-to-device communication control information, where the device-to-device communication signal is data exchanged between the user equipment and the another user equipment.
According to another aspect, a user equipment is provided, where the user equipment includes:
a second capability receiving unit, configured to receive a base station capability indication transmitted by a base station, where the base station capability indication indicates a capability, of heterogeneous device-to-device communication transmission is supported by the base station;
a control information receiving unit, configured to receive, through a first transmission channel established by the base station, device-to-device communication control information sent by the base station, where the first transmission channel is established in a network that is supported by the base station serving the user equipment, and is used to transmit the device-to-device communication control information to the user equipment, where the device-to-device communication control information is control signaling for controlling the user equipment to perform data exchange with another user equipment; and
a signal transmitting unit, configured to perform transmission of a device-to-device communication signal with the another user equipment according to the device-to-device communication control information, where the device-to-device communication signal is data exchanged between the user equipment and the another user equipment.
According to still another aspect, a wireless communications system is provided, where the wireless communications system includes the base station described above and the user equipment described above.
In the embodiments of the present invention, after a base station and a user equipment exchange a supported capability of heterogeneous device-to-device communication transmission, the base station can establish a first transmission channel for device-to-device communication control information according to a user plane or a control plane of a network in which the user equipment is located, and transmit the device-to-device communication control information to the user equipment through the first transmission channel; and then communication can be performed between user equipment's according to the device-to-device communication control information.
To make the objectives, technical solutions, and advantages of the present invention clearer and more comprehensible, the following further describes the present invention in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely used to explain the present invention but are not intended to limit the present invention.
In the embodiments of the present invention, after a base station and a user equipment exchange a supported capability of heterogeneous device-to-device communication transmission, the base station can establish a first transmission channel according to a user plane or a control plane of a network in which the user equipment is located, and transmit device-to-device communication control information to the user equipment through the first transmission channel; and then communication can be performed between user equipment according to the device-to-device communication control information.
The following describes implementation of the present invention in detail with reference to specific embodiments:
Scenario 1 in
S301: A base station receives a device capability indication of a user equipment, where the device capability indication indicates a capability of heterogeneous device-to-device communication transmission is supported by the user equipment.
In this embodiment, the user equipment may be a phone, a notebook computer, or the like, may also be another portable device, such as a tablet and a mobile wireless router; and the user equipment is outside coverage of an LTE/LTE-A or a subsequent enhanced protocol version network, for example, the user equipment is in a 2G/3G/WiFi network. The user equipment and the base station communicate a capability that multi-mode D2D transmission of multi-mode device-to-device communication is supported, that is, the user equipment and the base station need to know a capability of heterogeneous device-to-device communication transmission is supported by the other party, so as to support a heterogeneous device-to-device communication transmission mode. The capability of heterogeneous device-to-device communication transmission means that user equipment's in a non LTE/LTE-A or a non-subsequent enhanced protocol version network can directly perform data communication, and transmit data to each other.
A specific manner that the base station and the user equipment exchange information of the capability of heterogeneous device-to-device communication transmission may include:
The user equipment (User Equipment, UE) sends a device capability indication to the base station by using a capability reporting mechanism, to notify the base station of the capability of heterogeneous device-to-device communication transmission is supported by the UE. Certainly, an indication command (for example, user subscription information) sent by a core network may also be used to notify the base station of the capability of heterogeneous device-to-device communication transmission is supported by the UE. The device capability indication may be an explicit independent identifier, or may be an implicit independent identifier, which is indicated by another cell that can represent the capability of the UE, for example, a multi-mode transmission capability identifier and a multi-mode relay transmission capability identifier.
S302: The base station sends a base station capability indication to the user equipment, where the base station capability indication indicates a capability of heterogeneous device-to-device communication transmission is supported by the base station.
In this embodiment, the base station may use a broadcast message or individual dedicated signaling to notify each user equipment UE of a capability that the base station supports multi-mode device-to-device communication transmission. The base station capability indication may be an explicit independent identifier, or may be an implicit, which is indicated by another cell that can represent the capability of the base station, for example, a multi-mode transmission capability identifier and a multi-mode relay transmission capability identifier.
It should be noted that there is no limitation on a sequence of S301 and S302 during execution.
S303: The base station establishes a first transmission channel, where the first transmission channel is established in a network that is supported by the base station serving the user equipment, and is used to transmit device-to-device communication control information to the user equipment, where the device-to-device communication control information is control signaling for controlling the user equipment to perform data exchange with another user equipment.
In this embodiment, if D2D signal transmission in which a D2D transmission capability is supported needs to be initiated, the first transmission channel through which the D2D control information for supporting the D2D transmission capability may be transmitted needs to be established between the base station and each user equipment. According to different situations, establishment of the first transmission channel may be initiated according to a first indication of the user equipment, or be initiated by the base station. The base station can establish the first transmission channel according to a control plane connection, a user plane connection, or a wireless connection. Different cases are separately discussed as follows:
1. If the D2D control information is transmitted by using a control plane of a network of another mode, where the another mode specifically refers to a mode of a network in which the user equipment is located, and the another mode is a network mode different from LTE/LTE-A or a subsequent enhanced protocol version, including 2G/3G or the like, the base station uses a control plane connection channel between the base station and the user equipment as the first transmission channel, uses the first transmission channel to transmit the D2D control information, and carries an identifier in transmitted control signaling, where the identifier is used to indicate that the control signaling carries the device-to-device communication control information.
The control plane connection is a connection used to transmit signaling, and may also be called a signaling connection. The control plane connection corresponds to one or more bearers on a wireless air interface, and these bearers are called signaling radio bearers (Signaling Radio Bearer, SRB) or signaling bearers for short.
2. If the D2D control information is transmitted by using a user plane of a network of another mode, where the another mode specifically refers to a mode of a network in which the user equipment is located, and the another mode is a network mode different from LTE/LTE-A or a subsequent enhanced protocol version, including 2G/3G, the base station establishes one or more new user plane bearers, selects one user plane bearer from the multiple new user plane bearers as the first transmission channel, and notifies the user equipment of the first transmission channel, where the first transmission channel is used to transmit a dedicated data radio bearer (Data Radio Bearer, DRB) of the D2D control information, and the base station selects one user plane bearer from the multiple new user plane bearers as the first transmission channel according to a quality of service QoS requirement and data volume of exchange signaling between the base station and the user equipment; or, the base station selects one user plane bearer from one or more existing user plane bearers of the user equipment as the first transmission channel, and carries an identifier in a packet transmitted through the first transmission channel, where the identifier is used to indicate that the packet carries the device-to-device communication control information, so as to differentiate from other user plane data of the user equipment UE, and the identifier may be an IP address carried in the packet.
Specifically, an existing mechanism that a base station at a 2G/3G network side initiates establishment of a bearer can be used to establish a new dedicated user plane bearer.
A user plane includes one or more bearers on an air interface, and these bearers are called user plane bearers or may also be called data radio bearers (Data Radio Bearer, DRB).
3. For a network mode in which a control plane and a user plane are not differentiated on a wireless air interface, for example, a GSM network and WiFi/WiMAX, when the user equipment is in the network mode, the base station establishes one or more new wireless connections and selects one wireless connection from the multiple new wireless connections as the first transmission channel; or, the base station selects one wireless connection from one or more existing wireless connections of the user equipment as the first transmission channel, and carries an identifier in a packet transmitted through the existing wireless connection, where the identifier is used to indicate that the packet carries the device-to-device communication control information.
The wireless connection may refer to a specific radio time and frequency resource, for example, a channel, a timeslot, or the like.
S304: The base station sends the device-to-device communication control information to the user equipment through the first transmission channel, so that the user equipment performs transmission of a device-to-device communication signal with the another user equipment according to the device-to-device communication control information, where the device-to-device communication signal is data exchanged between the user equipment and the another user equipment.
In this embodiment, after a channel through which the device-to-device communication control information is transmitted is established between the base station and the user equipment, the base station can transmit the device-to-device communication control information to the user equipment through the channel, and the user equipment can perform transmission of a device-to-device communication signal with the another user equipment according to the received device-to-device communication control information. The device-to-device communication control information is information for controlling device-to-device communication D2D signal transmission in the LTE/LTE-A or the subsequent enhanced protocol version network, including: one piece or a combination of layer 2 signaling and layer 3 signaling for controlling the D2D signal transmission, and layer 1 information for controlling the D2D signal transmission, including one piece or a combination of: channel quality information, time synchronization information, frequency synchronization information, power information, and scheduling information. Layer 1 refers to a physical layer, layer 2 refers to a MAC layer, and layer 3 refers to an RRC layer. The device-to-device communication signal refers to data transmitted between user equipment when the user equipment directly perform data communication.
In this embodiment, after a base station and a user equipment exchange a supported capability of heterogeneous device-to-device communication transmission, the base station can establish a first transmission channel according to a network in which the user equipment is located, and transmit device-to-device communication control information to the user equipment through the first transmission channel; and then communication can be performed between user equipment according to the device-to-device communication control information. The network in which the user equipment is located may be another network different from an LTE/LTE-A or a subsequent enhanced protocol version network. Therefore, in the embodiment of the present invention, although the user equipment is in a heterogeneous network different from the LTE/LTE-A or the subsequent enhanced protocol version network, the user equipment still can support transmission of a device-to-device communication signal.
In step S601, a user equipment receives a base station capability indication transmitted by a base station, where the base station capability indication indicates a capability of heterogeneous device-to-device communication transmission is supported by the base station.
By performing step S601, the user equipment can learn the capability of heterogeneous device-to-device communication transmission is supported by the base station.
In step S602, the user equipment sends a first indication to the base station, so that the base station establishes a first transmission channel according to the first indication, where the first transmission channel is established in a network that is supported by the base station serving the user equipment, and is used to transmit device-to-device communication control information to the user equipment, where the device-to-device communication control information is control signaling for controlling the user equipment to perform data exchange with another user equipment, and the first indication includes signaling that instructs the base station to establish the first transmission channel.
As an embodiment of the present invention, before step S602, the method may further include the following steps:
The user equipment sends a device capability indication to the base station, where the device capability indication indicates a capability of heterogeneous device-to-device communication transmission is supported by the user equipment. By performing this step, the base station can learn that the user equipment supports the capability of heterogeneous device-to-device communication transmission. The device capability indication may also be sent to the base station by using a core network, which is not limited herein.
In step S603, the user equipment receives, through the first transmission channel established by the base station, the device-to-device communication control information sent by the base station.
In this embodiment, after the base station and the user equipment learn a capability of heterogeneous device-to-device communication transmission is supported by the other party, the user equipment sends an indication to the base station; after receiving the indication, the base station establishes the first transmission channel according to a mode of a network in which the user equipment is located and based on the network with the mode, and transmits the device-to-device communication control information to the user equipment through the first transmission channel; and then communication can be performed between user equipment's that receive the device-to-device communication control information and according to the device-to-device communication control information. The device-to-device communication control information is information for controlling device-to-device communication D2D signal transmission in an LTE/LTE-A or a subsequent enhanced protocol version network, including: one piece or a combination of layer 2 signaling and layer 3 signaling for controlling the D2D signal transmission, and layer 1 information for controlling the D2D signal transmission, including one piece or a combination of: channel quality information, time synchronization information, frequency synchronization information, power information, and scheduling information. Layer 1 refers to a physical layer, layer 2 refers to a MAC layer, and layer 3 refers to an RRC layer.
In step S604, the user equipment performs transmission of a device-to-device communication signal with the other user equipment according to the device-to-device communication control information, where the device-to-device communication signal is data exchanged between the user equipment and the other user equipment.
In this embodiment, after a base station and a user equipment exchange a supported capability of heterogeneous device-to-device communication transmission, the base station can establish a first transmission channel according to a network in which the user equipment is located, and transmit device-to-device communication control information to the user equipment through the first transmission channel; and then communication can be performed between user equipments according to the device-to-device communication control information. The network in which the user equipment is located may be another network different from an LTE/LTE-A or a subsequent enhanced protocol version network. Therefore, in the embodiment of the present invention, although the user equipment is in a heterogeneous network different from the LTE/LTE-A or the subsequent enhanced protocol version network, the user equipment still can support transmission of a device-to-device communication signal.
The first capability receiving unit 71 is configured to receive a device capability indication of a user equipment, where the device capability indication indicates a capability of heterogeneous device-to-device communication transmission is supported by the user equipment; and the capability receiving unit 71 receives the device capability indication of the user equipment that is transmitted to the base station by the user equipment and/or a core network.
The first capability sending unit 72 is configured to send a base station capability indication to the user equipment, where the base station capability indication indicates a capability of heterogeneous device-to-device communication transmission is supported by the base station.
The channel establishing unit 73 is configured to establish a first transmission channel, where the first transmission channel is established in a network that is supported by the base station serving the user equipment, and is used to transmit device-to-device communication control information to the user equipment, where the device-to-device communication control information is control signaling for controlling the user equipment to perform data exchange with another user equipment; and the channel establishing unit 73 may establish the first transmission channel according to an indication initiated by the user equipment, or the base station may initiate establishment of the first transmission channel by itself.
The control information transmitting unit 74 is configured to send the device-to-device communication control information to the user equipment through the first transmission channel, so that the user equipment performs transmission of a device-to-device communication signal with the another user equipment according to the device-to-device communication control information, where the device-to-device communication signal is data exchanged between the user equipment and the another user equipment.
Specifically, the channel establishing unit 73 includes:
a first channel establishing module, configured to use a control plane connection with the user equipment as the first transmission channel, and carry an identifier in control signaling transmitted through the first transmission channel, where the identifier is used to indicate that the control signaling carries the device-to-device communication control information.
Specifically, the channel establishing unit 73 includes:
a second channel establishing module, configured to establish one or more new user plane bearers and select one user plane bearer from the multiple new user plane bearers as the first transmission channel.
Specifically, the channel establishing unit 73 includes:
a third channel establishing module, configured to select one user plane bearer from one or more existing user plane bearers of the user equipment as the first transmission channel, and carry an identifier in a packet transmitted through the first transmission channel, where the identifier is used to indicate that the packet carries the device-to-device communication control information.
Specifically, the channel establishing unit 73 includes:
a fourth channel establishing module, configured to establish one or more new wireless connections and select one wireless connection from the new wireless connections as the first transmission channel.
Specifically, the channel establishing unit 73 includes:
a fifth channel establishing module, configured to select one wireless connection from one or more existing wireless connections of the user equipment as the first transmission channel, and carry an identifier in a packet transmitted through the first transmission channel, where the identifier is used to indicate that the packet carries the device-to-device communication control information.
For details about an execution situation of each unit in the base station, reference may be made to description of the method shown in
The second capability receiving unit 81 is configured to receive a base station capability indication transmitted by a base station, where the base station capability indication indicates a capability of heterogeneous device-to-device communication transmission is supported by the base station.
The control information receiving unit 82 is configured to receive, through a first transmission channel established by the base station, device-to-device communication control information sent by the base station, where the first transmission channel is established in a network that is supported by the base station serving the user equipment, and is used to transmit the device-to-device communication control information to the user equipment, where the device-to-device communication control information is control signaling for controlling the user equipment to perform data exchange with another user equipment.
The signal transmitting unit 83 is configured to perform transmission of a device-to-device communication signal with the other user equipment according to the device-to-device communication control information, where the device-to-device communication signal is data exchanged between the user equipment and the other user equipment.
Further, the user equipment further includes: an indication sending unit, where the unit is configured to send a first indication to the base station, so that the base station establishes the first transmission channel according to the first indication.
Further, the user equipment further includes: a second capability sending unit, where the unit is configured to send a device capability indication to the base station, where the device capability indication indicates a capability of heterogeneous device-to-device communication transmission is supported by the user equipment.
For details about an execution situation of each unit in the user equipment, reference may be made to description of the method shown in
It should be noted that, in the foregoing system embodiments, the included units are classified merely according to functional logic, but the present invention is not limited to the above classification, as long as corresponding functions can be implemented. In addition, the specific names of the functional units are merely for facilitating the differentiation between each other, but are not intended to limit the protection scope of the present invention.
In addition, a person of ordinary skill in the art may understand that all or a part of the steps of the methods in the embodiments may be implemented by a program instructing relevant hardware. A corresponding program may be stored in a computer readable storage medium, where the storage medium includes a ROM/RAM, a magnetic disk, an optical disc, or the like.
The foregoing descriptions are merely embodiments of the present invention, but are not intended to limit the present invention. Any modification, equivalent replacement, or improvement made without departing from the spirit and principle of the present invention shall fall within the protection scope of the present invention.
Number | Date | Country | Kind |
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201210268817.8 | Jul 2012 | CN | national |
This application is a continuation of International Application No. PCT/CN2013/080497, filed on Jul. 31, 2013, which claims priority to Chinese Patent Application No. 201210268817.8, filed on Jul. 31, 2012, both of which are hereby incorporated by reference in their entireties.
Number | Date | Country | |
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Parent | PCT/CN2013/080497 | Jul 2013 | US |
Child | 14600752 | US |