JP6659818B2 - User equipment, communication system, and method for controlling user equipment - Google Patents

Description

  Embodiments of the present invention relate to a mobile communication system. Embodiments of the present invention specifically relate to techniques for performing device-to-device discovery and / or device-to-device communication in a mobile communication network.

  The demand for data and voice mobile communications continues to demonstrate significant growth. Examples of mobile communication systems include cellular-based wireless communication networks. Such a network includes various network nodes. These network nodes may include multiple base stations that each provide coverage for a wireless cell.

  The user equipment of the mobile communication network may be a proximity service (ProSe) enabled device. Some ProSe-enabled user equipment located in close proximity to each other operates to implement device-to-device (D2D) communication. D2D communication allows mobile user equipment of a mobile communication network to communicate directly with one another when they are positioned in close proximity to each other. D2D communication has a wide variety of uses, including public safety and other use cases. Emergency calling is one example of a public safety use case for D2D communication. Direct data or voice communication between user devices is another example of a use case for D2D communication. By way of example, ProSe-enabled user equipment positioned proximate to one another may participate in data or voice communications.

  In order to implement D2D communication, a user equipment must be able to detect one or several other user equipments located in close proximity to the user equipment.

  Resources, eg, subcarrier frequencies, slots, and / or symbols that the user equipment may use for D2D discovery may be assigned to the user equipment by the base station. Similarly, resources, eg, subcarrier frequencies, slots, and / or symbols that a user equipment may use for D2D communication may be assigned to the user equipment by a base station. Transmission of data as D2D communication may require scheduling assignment. The scheduling assignment may be used to determine on which resources the user equipment may transmit or receive data, for example, on which subcarrier frequencies, slots, and / or symbols.

  The user equipment may perform D2D discovery and / or communication even when it is located outside the coverage of the cellular communication network. Resources for scheduling assignment, or data resources, may be pre-configured by the cellular communication network. The pre-configured resources available for D2D discovery and / or D2D communication in out-of-coverage scenarios may be limited. The reason is in particular that the pre-configured resources must match the radio access network resources of some neighboring cells of the cellular communication network.

  There is a need in the art for a technique that mitigates at least some of the above disadvantages. In particular, in out-of-coverage scenarios, techniques are needed that address the shortcomings of the limitations imposed by pre-configured resources for device-to-device discovery and / or device-to-device communication. There is a need for a technique that reduces the risk that device-to-device discovery and / or device-to-device communication will cause interference with a cellular communication network's radio access network.

  According to an exemplary embodiment of the present invention, resources for device-to-device discovery and / or device-to-device communication are dynamically adjusted. Hereinafter, these resources are referred to as device-to-device resources.

  According to embodiments, extended resources are provided for device-to-device discovery and / or device-to-device communication when one or several user equipments are present or move out of coverage of the cellular communication network. Be dynamically available. When one or more user equipments are in the coverage of the cell or in the partial coverage, the extended resources are resources reserved for communication with the radio access network of the cellular communication network. Can be Thereby, resources that are not needed in out-of-coverage scenarios are made dynamically available for device-to-device discovery and / or device-to-device communication. Problems related to lack of device-to-device resources can be mitigated. The extension resources may include a greater number of subcarrier frequencies than the number of subcarrier frequencies of the pre-configured device-to-device resources.

  The use of extended resources may be implemented selectively depending on whether one or all devices of the device-to-device group are located out of coverage or move out of coverage. The use of extended resources may be implemented selectively depending on the signal-to-noise-and-interference ratio (SINR) measured by all devices in the device-to-device group. Extended resources may be used only if the SINR for each device is below a threshold. The threshold used to determine whether extended resources can be used can be less than a further threshold for SINR, which determines whether the device is within coverage.

  A user equipment according to one embodiment comprises a wireless interface configured for communication with a cellular communication network. The user equipment comprises a processing device configured to control the wireless interface to use device-to-device resources for device-to-device discovery and / or device-to-device communication. Device-to-device resources depend on whether the user equipment is outside the coverage of the cellular communication network.

  The user equipment may provide enhanced resources for device-to-device discovery and / or device-to-device communication, at least when the user equipment moves out of the coverage of the cellular communication network or is present outside the coverage of the cellular communication network. The use may be configured to be selectively enabled.

  Resources employed from a resource pool configured by the extended resources to perform device-to-device discovery and / or device-to-device communication when the use of the extended resources is enabled; Resources can be used.

  The user equipment is provided for device-to-device discovery and / or device-to-device communication when all devices of the device-to-device group move out of the coverage of the cellular communication network or are present outside the coverage of the cellular communication network. May be configured to be enabled. The device to device group includes user equipment.

  The user equipment may be configured to perform device-to-device discovery and / or device-to-device communication when at least one device of the device-to-device group moves into or is within the coverage of the cellular communication network. May be configured to disable the use of extended resources for

  The user equipment controls the wireless interface to transmit information indicating that the user equipment has moved out of the coverage of the cellular communication network or that the user equipment is out of the coverage of the cellular communication network. May be configured.

  The user equipment may be configured to receive a message at the wireless interface in response to the information, wherein the message uses the extended resource for device-to-device discovery and / or device-to-device communication. Enable.

  The user equipment may be configured to receive a message from a group head of a device-to-device group. The group head may thereby implement control signaling that causes all devices in the device-to-device group to use the extended resources.

  The user equipment may be configured to receive another message from a group head of the device-to-device group that disables the user equipment from using resource extensions for device-to-device discovery and / or device-to-device communication. The group head may implement control signaling thereby causing all devices in the device-to-device group to stop using the extended resource.

  The user equipment may be configured to use the extended resources for communication with the cellular communication network when the use of the extended resources for device-to-device discovery and / or device-to-device communication is not enabled.

  The user equipment may be configured to use the extension resources as scheduling assignment resources and as data resources. In this case, both scheduling assignment resources for transmitting or receiving scheduling assignments and data resources for sending or receiving data via device-to-device communication may be included in the extension resources.

  The scheduling assignment resources and data resources in the extension resources may be associated with the original scheduling assignment resources and the original data resources, for example, by frequency and / or time offsets. The offset information can be pre-configured or signaled by the group head.

  The user equipment may be configured to use the extended resources as data resources and use resources different from the extended resources as scheduling assignment resources. The scheduling assignment in the original pre-configured scheduling assignment resource is then used to dynamically link the data resource in the extended resource to the original data resource in the pre-configured device-to-device resource. Can be done.

  The user equipment may be configured to trigger execution of at least one service, depending on whether the use of extended resources for device-to-device discovery and / or device-to-device communication is enabled. At least one service may have a bandwidth requirement that is above a bandwidth threshold.

  The at least one service may include a video call service.

  The user equipment may be configured to operate as a group head of a device-to-device group. To that end, the user equipment may monitor whether the devices of the device-to-device group are in or out of coverage of the cellular communication network. If all devices in the device-to-device group are out of coverage, the user equipment allows all devices in the group to use the extended resources for device-to-device discovery and / or device-to-device communication Can be. If any one of the devices in the device-to-device group is in coverage, the user equipment may disable the use of extended resources for device-to-device discovery and / or device-to-device communication.

  The user equipment may broadcast commands to enable and disable the use of extended resources for device-to-device discovery and / or device-to-device communication, respectively.

  User equipment may implement dedicated signaling to enable and disable use of extended resources for device-to-device discovery and / or device-to-device communication, respectively.

  According to another embodiment, there is provided user equipment configured to act as a group head of a device-to-device group. The user equipment comprises a wireless interface configured for communication with a cellular communication network. The user equipment receives information from the at least one further user interface at the wireless interface indicating whether the at least one further user equipment is within the coverage of the cellular communication network or outside the coverage. It is composed of The user equipment may be configured for at least one device for device-to-device discovery and / or device-to-device communication, depending on whether at least one further user equipment is within or outside the coverage of the cellular communication network. It is configured to control device-to-device resources used by one further user equipment.

  The user equipment may be configured for device-to-device discovery and / or device-to-device communication by the at least one further user equipment when both the at least one further user equipment and the user equipment are outside the coverage of the cellular communication network. May be configured to selectively enable the use of resource extensions for

  The user equipment is provided for device-to-device discovery and / or device-to-device communication by the at least one further user equipment when the at least one further user equipment or the user equipment is within the coverage of the cellular communication network. It may be configured to selectively disable the use of resource extensions.

  A communication system according to one embodiment comprises a device-to-device group. The device to device group includes a plurality of devices configured for communication with the cellular communication network, and each device of the device to device group is further configured for device to device discovery and device to device communication. At least one device of the device-to-device group is configured as user equipment according to one embodiment.

  A device to device group may include a group head. The group head may be configured to determine whether all devices in the device-to-device group move out of coverage of the cellular communication network or are out of coverage of the cellular communication network. The group head may be configured to selectively enable multiple devices to use the extended resources for device-to-device discovery and / or device-to-device communication.

  The group head may be configured to perform device-to-device discovery and / or device-to-device communication when at least one device of the device-to-device group moves into or is within the coverage of the cellular communication network. May be further configured to disable the use of extended resources for

  According to one embodiment, a method for controlling user equipment is provided. The user equipment comprises a wireless interface configured for communication with a cellular communication network. The method includes determining whether the user equipment moves out of coverage of the cellular communication network or is out of coverage. The method includes using device-to-device resources for device-to-device discovery and / or device-to-device communication over a wireless interface, wherein the device-to-device resources allow a user equipment to move out of coverage of a cellular communication network. Or out of coverage.

  The method may be performed by a user equipment or a communication system according to one embodiment.

  In this method, the use of extended resources for device-to-device discovery and / or device-to-device communication may be at least when the user equipment moves out of or is outside the coverage of the cellular communication network. Alternatively, it can be selectively enabled.

  Resources employed from a resource pool configured by the extended resources to perform device-to-device discovery and / or device-to-device communication when the use of the extended resources is enabled; Resources can be used.

  In this method, when all devices of the device-to-device group move out of the coverage of the cellular communication network or are present outside the coverage of the cellular communication network, the device is used for device-to-device discovery and / or device-to-device communication. May be enabled. The device to device group includes user equipment.

  In this method, when at least one device of the device-to-device group moves within the coverage of the cellular communication network or is present in the coverage of the cellular communication network, the device-to-device discovery and / or communication of the device-to-device communication is performed. The use of extended resources for storage may be disabled.

  The method may include transmitting information over a wireless interface of the user equipment indicating that the user equipment has moved out of coverage of the cellular communication network or that the user equipment is out of coverage of the cellular communication network. .

  The method may include receiving a message at a wireless interface in response to the information. The message may enable the user equipment to use the extended resources for device-to-device discovery and / or device-to-device communication.

  The message may be sent by the group head of the device-to-device group. The group head may thereby implement control signaling that causes all devices in the device-to-device group to use the extended resources.

  The method may include receiving another message from a group head of the device-to-device group that disables user equipment from using resource extensions for device-to-device discovery and / or device-to-device communication. The group head may implement control signaling thereby causing all devices in the device-to-device group to stop using the extended resource.

  The group head may send another message that disables device-to-device discovery and / or the use of resource extensions for device-to-device communication when at least one device of the device-to-device group moves into the coverage of the cellular communication network. Can send.

  The method may include using the extended resources for communication with a cellular communication network when the use of the extended resources for device-to-device discovery and / or device-to-device communication is not enabled.

  Extended resources may be used as scheduling assignment resources and as data resources. In this case, both scheduling assignment resources for transmitting or receiving scheduling assignments and data resources for sending or receiving data via device-to-device communication may be included in the extension resources.

  In this manner, the scheduling assignment resources and data resources in the extension resources may be associated with the original scheduling assignment resources and the original data resources, for example, by frequency and / or time offsets. The offset information can be pre-configured or signaled by the group head.

  Extended resources may be used as data resources. Resources different from the extension resources may be used as scheduling assignment resources. The scheduling assignment in the original pre-configured scheduling assignment resource is then used to dynamically link the data resource in the extended resource to the original data resource in the pre-configured device-to-device resource. Can be done.

  The method may include performing at least one service depending on whether extended resource usage for device-to-device discovery and / or device-to-device communication is enabled. At least one service may have a bandwidth requirement that is above a bandwidth threshold.

  The at least one service may include a video call service.

  The method may include monitoring by the user equipment whether all devices of the device-to-device group are outside the coverage of the cellular communication network.

  The method may include transmitting a message to enable the use of the extended resource by the user equipment to the device-to-device group when all devices of the device-to-device group are out of coverage.

  The method may include sending another message by the user equipment to the device-to-device group that disables use of the extended resource when at least one device of the device-to-device group moves into coverage.

  In this way, the user equipment may broadcast commands to enable and disable the use of extended resources for device-to-device discovery and / or device-to-device communication, respectively.

  In this way, the user equipment may implement dedicated signaling to enable and disable the use of extended resources for device-to-device discovery and / or device-to-device communication, respectively.

  In methods, devices, and systems according to embodiments, user equipment may be enabled to use extended resources for device-to-device discovery and / or device-to-device communication. Device-to-device resources may thereby be dynamically increased when user devices as well as other devices within the same device-to-device group are out of coverage, and may be associated with a cellular communication network's radio access network. No interference problems can occur.

  While certain features described in the foregoing summary and the following detailed description are set forth in the context of particular embodiments and aspects of the present invention, these features of these embodiments and aspects are not specifically described. May be combined unless otherwise noted.

  Embodiments of the present invention will now be described in more detail with reference to the accompanying drawings, in which similar or identical reference numbers indicate similar or identical elements.

FIG. 1 illustrates a communication system according to one embodiment. FIG. 2 shows the communication system of FIG. 1 in which all devices of the device-to-device group are out of coverage. FIG. 3 shows the communication system of FIG. 1 where one device of the device-to-device group is in coverage. FIG. 4 is a block diagram representation of a communication system according to one embodiment. FIG. 5 is a diagram illustrating resources for device-to-device discovery and / or device-to-device communication when extended resource usage is not enabled. FIG. 6 is a diagram illustrating resources for device-to-device discovery and / or device-to-device communication when extended resource usage is enabled. FIG. 7 is a diagram illustrating resources for device-to-device discovery and / or device-to-device communication when extended resource usage is enabled. FIG. 8 is a flowchart of a method according to one embodiment. FIG. 9 is a flowchart of a method according to one embodiment. FIG. 10 is a diagram illustrating signaling in a communication system according to an embodiment. FIG. 11 is a diagram illustrating signaling in a communication system according to an embodiment. FIG. 12 is a flowchart of a method according to one embodiment. FIG. 13 is a functional block diagram of a user device according to an embodiment. FIG. 14 is a diagram illustrating a quality indicator that may be monitored to selectively enable users of extended resources.

  Hereinafter, exemplary embodiments of the present invention will be described in more detail. It should be understood that features of the various exemplary embodiments described herein may be combined with each other, unless otherwise noted. Identical or similar reference numbers refer to identical or similar components.

  Although the exemplary embodiments are described with reference to certain use cases for device-to-device (D2D) communication, it should be understood that the technology for D2D discovery and communication is a public safety use case. And can be used for a wide variety of use cases, including other commercial use cases. Illustrative embodiments are described in the context of certain cellular mobile communication networks, for example, Long Term Evolution (LTE) networks, but these embodiments are not described in such mobile communication technologies.

  Although the exemplary embodiment will be described with reference to a base station with pre-configured device-to-device resources, it should be understood that the user equipment may be, for example, a repeater relay or a group head for D2D communication. In that it can also receive information about pre-configured device-to-device resources from another user device that acts as a.

  FIG. 1 shows a communication system 1 according to one embodiment. Communication system 1 includes a mobile communication system configured as a cellular communication network. A cellular communication network may comprise a plurality of base stations, each serving a cell. FIG. 1 schematically shows a base station 11 and an associated cell 9. Base stations may communicate with one another via wireless radio communication or via an operator core network. The cellular communication network may be an LTE (Long Term Evolution) network. The radio access network (RAN) of the cellular communication network may be an evolved UTRAN (E-UTRAN), and the base station 11 is an evolved Node B (eNodeB). The base station may be connected to a mobility management entity (MME) and / or a serving gateway (S-GW) in the operator core network.

  The base station 11 provides a radio cell 9 in which user equipment (UEs) 2, 3, and 4 can communicate directly with the base station 11 via a radio communication 8. UEs 2, 3, and 4 may each have a wireless interface for communication with a RAN of a cellular communication network.

  At least one of the UEs 2, 3, and 4 is capable of performing D2D discovery and D2D communication. According to terminology in the relevant field of the art, the term D2D communication refers to radio communication between UEs, which is implemented directly between UEs. Radio signals 5, 6, and 7 transmitted in D2D discovery and / or D2D communication may not be processed by base stations of the cellular communication network. Radio signals 5, 6, and 7 transmitted in D2D discovery and / or D2D communication may not pass through the RAN of the cellular communication network. Radio signals 5, 6, and 7 transmitted in D2D discovery and / or D2D communication may not be processed by the core network of the wireless cellular communication network. UEs configured for D2D discovery and D2D communication may use the same wireless interface to communicate with the RAN and for D2D purposes. UEs configured for D2D discovery and D2D communication may also be referred to in the art as proximity service (ProSe) enabled UEs.

  UEs 2, 3, and 4 configured for D2D discovery and / or D2D communication may use pre-configured resources for D2D discovery signaling and / or for D2D communication. By way of example, at least the resources for the scheduling assignment may be pre-configured by the cellular communication network. The pre-configured resources may be pre-configured at UEs 2, 3, and 4 by base station 11, a repeater relay, or another UE. Resources pre-configured for D2D discovery and / or D2D communication may be allocated by the base station 11 by broadcast or multicast messages, or by dedicated signaling, respectively. By way of example, UEs 2, 3, and 4 may each receive information about assigned resources for D2D discovery signaling in a system information block (SIB) that may be transmitted by a cellular communication network. Alternatively, dedicated signaling may be used.

  In the following, resources that may be used by UEs 2, 3, and 4 for D2D discovery and / or D2D communication are also referred to as device-to-device resources. D2D resources may include resources pre-configured by the cellular communication network. As will be described in more detail below with reference to FIGS. 1 to 14, the device-to-device resource depends on how one or more UEs are located with respect to the coverage area of the cellular communication network. And can be adjusted dynamically.

  By way of example, the use of extended resources can be dynamically enabled if all UEs 2, 3, and 4 included in the device-to-device group are present or move out of coverage of the cellular communication network Can be done.

  If one or some of the UEs 2, 3, and 4 move into or are located within the coverage of the cellular communication network, use of the extended resources may be disabled. In this case, the extended resources may be placed independent of D2D discovery signaling and / or D2D communication and used for communication with the RAN of the cellular communication network.

  The extended resource may be an out-of-coverage (OoC) extended resource that is selectively used for D2D discovery and / or D2D communication only when the UE is outside the coverage of the cellular communication network. Extended resources are selective for D2D discovery and / or D2D communication only if all UEs are outside the coverage of the cellular communication network and are unlikely to cause interference with the RAN when using the extended resources. Can be used for

  1 to 3 illustrate various conditions of a communication system according to one embodiment. The plurality of UEs 2, 3, and 4 may form a device-to-device group.

  FIG. 1 shows the conditions under which the UEs 2, 3, and 4 of the device-to-device group are all located within the coverage of the cellular communication system. Device-to-device resources may be pre-configured by the cellular communication network via wireless signaling. Device to device resources may be pre-configured for the case where one or some of UEs 2, 3, and 4 move out of coverage.

  FIG. 2 shows a condition in which the UEs 2, 3, and 4 of the device-to-device group are all located outside the coverage of the cellular communication system. In this case, use of extended resources for D2D discovery and / or D2D communication. Extended resources may be used for D2D discovery and / or D2D communication in addition to the original pre-configured D2D resources.

  Various techniques may be used to combine the extended resources with the original pre-configured D2D resources. By way of illustration, extension resources may be used for both scheduling assignments and data. There may be a relationship between the resources in the extended resources and the original pre-configured D2D resources, the relationship being that the resources in the extended resources are replaced in the original pre-configured D2D resources. Link to a resource. For further illustration, the extension resources may be used for data only and all scheduling assignments are kept in the original pre-configured D2D resources. The scheduling assignment in the original pre-configured D2D resource then provides a link to the extended resource where the respective data is transmitted.

  FIG. 3 shows conditions under which at least one of the UEs has moved into the coverage of the cellular communication network. The use of extended resources for D2D discovery and / or D2D communication may be disabled for all UEs 2, 3, and 4 of the group. D2D discovery and / or D2D communication may be limited to pre-configured resources. The extended resources are made available again for communication with the radio access network.

  The extension resources may include a greater number of resource blocks in the time-frequency resource grid than the number of resource blocks of the initially configured D2D resource. The extension resources may include a greater number of subcarrier frequencies in the time-frequency resource grid than the number of subcarrier frequencies of the initially configured D2D resource.

  That the UEs 2, 3, and 4 of the device-to-device group adapt D2D resources, depending on whether all UEs 2, 3, and 4 of the device-to-device group are located outside the coverage of the cellular communication network Various techniques may be used to enable

  In some implementations, UEs 3 in a device-to-device group may serve as group heads. UE3 acting as the group head may receive a report from the other UEs 2 and 4 indicating whether each of the other UEs 2 and 4 in the group is in coverage or out of coverage. The report may include a signal quality indicator for the signal strength of the RAN. For illustration, the signal-to-noise-and-interference ratio (SINR) measured by other UEs 2 and 4 may be reported to UE 3 acting as a group head.

  If all UEs are out of coverage, UE3 acting as a group head may use one-to-many or one-to-one signaling to allow other UEs 2 and 4 in the group to extend for D2D discovery and / or D2D communication It may be possible to start using the resource. Additional criteria may be used to determine whether the use of extended resources for D2D discovery and / or D2D communication can be enabled. For illustration, the SINR measured by each UE 2, 3, and 4 in the device-to-device group may be compared to an activation threshold, which is less than a threshold at which a suitable cell is detected. Use of extended resources for D2D discovery and / or D2D communication may be selectively enabled only if the SINR for each UE 2, 3, and 4 of the device-to-device group is below an activation threshold. Similarly, the use of extended resources for D2D discovery and / or D2D communication may be disabled if the SINR detected by at least one of UEs 2, 3, and 4 is above an activation threshold.

  Alternatively or additionally, each of the UEs 2, 3 and 4 may or may not be in coverage to enable and disable use of the extended resources by the group head. Information about what to do may be broadcast to all other UEs 2, 3, and 4 in the same device-to-device group. Each of the UEs 2, 3, and 4 may track the status of all other UEs 2, 3, and 4 in the device-to-device group. If all UEs of the same device-to-device group are out of coverage, each UE may start using the extended resources for D2D discovery and / or D2D communication. If one UE of the same device-to-device group comes back into coverage, all UEs of the device-to-device group may disable the use of extended resources for D2D discovery and / or D2D communication.

  FIG. 4 is a schematic block diagram of the communication system 1 according to one embodiment.

  The UE 2 has a wireless interface 20. Wireless interface 20 may be configured to communicate with RAN 10. Wireless interface 20 may be configured for communication over an E-UTRA air interface.

  UE 2 has a processing device 24 connected to the wireless interface 20. The processing device 24 comprises one or several microprocessors, one or several microcontrollers, one or several processors, one or several controllers, one or several application specific integrated circuits. (ASIC) and / or a combination of such devices.

  The processing device 24 may be configured to retrieve information about the pre-configured D2D resources from the signaling received at the wireless interface 20 from the cellular communication network. Processing device 24 may be configured to control which resources may be used for D2D discovery and / or D2D communication. If all UEs 2, 3, and 4 in the device-to-device group are out of or move out of coverage of the cellular communication network, the processing device 24 will have a D2D compared to the original pre-configured resources. It can be configured to selectively increase the amount of resources. If one of the UEs 2, 3, and 4 moves within the coverage of the cellular communication network, the processing device 24 may be configured to selectively limit the D2D resources to the original pre-configured resources.

  The processing device 24 controls the transmitter path 23 of the wireless interface 20 to send a D2D discovery signal to the further UE 3 via the antenna 21 to confirm that the UE 2 is looking for a further UE for D2D communication. And / or indicate that the UE 2 will be able to perform D2D communication. The processing device 24 may be configured to use the selected resource from the D2D resources for transmission, which indicates whether UE2 and other UEs 3 and 4 in the same group are in coverage, or whether It depends on what is outside. The processing device 24 may be coupled to the receiver path 22 of the wireless interface 20 and process messages received from the group head 3 of the device-to-device group or another UE 4. For illustration, the processing device 24 may decode signaling from the group head 3 and / or other UEs 4 to determine whether the use of extended resources for D2D discovery and / or D2D communication may be enabled. obtain.

  The UE 3 serving as the group head and the other UEs 4 may have configurations and operations that substantially correspond to the configurations and operations described for UE 2. UE 3 may include a wireless interface 30 configured for communication with the RAN and UEs 2 and 4. The wireless interface 30 may include an antenna 31, a receiver path 32, and a transmitter path 32. UE 3 acting as a group head may include a processing device 34 coupled to wireless interface 30.

  The processing device 34 may be configured to determine whether all UEs 2, 3, and 4 of the device-to-device group are out of coverage. The processing device 34 controls the wireless interface to allow the UEs 2 and 4 to allocate extended resources for D2D discovery and / or D2D communication, depending on whether all UEs 2, 3, and 4 are out of coverage. It can be configured to selectively enable use. The processing device 34 may be configured to determine whether at least one of the UEs 2, 3, and 4 of the device-to-device group is within the coverage of the cellular communication network. The processing device 34 controls the wireless interface to select the use of extended resources for D2D discovery and / or D2D communication depending on whether at least one of the UEs 2, 3, and 4 is in coverage. Can be configured to be disabled.

  Other UEs 4 may have configurations and operations that substantially correspond to the configurations and operations described for UE2. UE 4 may include a wireless interface 25 configured for communication with the RAN and UEs 3 and 4. Wireless interface 25 may include an antenna 26, a receiver path 27, and a transmitter path 28. UE4 may comprise a processing device 29 coupled to wireless interface 25, which may be configured as described for the processing device of UE2.

  FIG. 5 illustrates a time-frequency resource grid. Resources may be subdivided into the time domain, for example, into frames 41 and 42, and into the frequency domain. In the frequency domain, multiple subcarrier frequencies may be available.

  The D2D resource 50 may be pre-configured, stored at the UE, for example, on a Universal Integrated Circuit Card (UICC), or stored by a cellular communication network. Extended resources 53 may be used when predefined criteria are met, for example, when all UEs in the device-to-device group are outside the coverage of the cellular communication network, and / or when the user is in a certain geolocation area. May be used only for D2D discovery and / or D2D communication. While at least one UE of the device-to-device group is in the coverage or partial coverage, the extended resources 53 may be configured to use D2D discovery and / or D2D to prevent interference with signaling and data transmission of the cellular communication network. It can be placed independent of communications.

  D2D resources 50 may include scheduling assignment (SA) resources 51. The scheduling assignment may be sent on SA resource 51. D2D resources 50 may include data resources 52 for data transmission. Data may be transmitted on subcarrier frequencies and symbols 62 of data resources 52. The subcarrier frequencies and symbols 62 may be specified by an associated scheduling assignment 61 in the SA resource 51.

  FIG. 6 illustrates one approach to using a time-frequency resource grid when all UEs in a device-to-device group are out of coverage.

  The D2D resource is dynamically extended to include an extended resource 53 in addition to the pre-configured initial D2D resource 50. In the resource usage scheme shown in FIG. 6, the extended resource 53 can be used as both an SA resource and a data resource. Scheduling assignment 63 may be transmitted in extension resource 53. Associated data may be transmitted on subcarrier frequencies and symbols 64 of extension resources 53.

  The subcarrier frequencies and / or symbols 63, 64, 65, and 66 of the extension resource 53 used for scheduling assignment transmission and data transmission are based on the respective subcarrier frequencies of the initial preconfigured D2D resource 50 and And / or may be linked to symbols 61 and 62. By way of example, the sub-carrier frequencies and / or symbols 63, 64, 65, and 66 of the extension resource 53 used for scheduling assignment transmission and data transmission may be the respective It may have a frequency offset and / or a time offset with respect to the subcarrier frequency and / or the symbols 61 and 62.

  The SA resource 61 and the data resource 62 in the preconfigured initial D2D resource 50 can be linked to each other by one-to-one mapping. By way of example, there may be a one-to-one mapping that links data resources 62 to SA resources 61 in the time-frequency resource grid of the pre-configured original D2D resources 50. This mapping may be reused for the extension resource 53, ie, the extension resource 53 is between the SA resource and the data resource in the time-frequency resource grid known from the pre-configured initial D2D resource 50. This mapping can be reused in order to take over the mapping to the extended resource 53. The mapping may include frequency and / or time offsets. For illustration, the SA resource 63 and the data resource 64 may have a first time and / or frequency offset relative to the SA resource 61 and the data resource 62 in the pre-configured initial D2D resource 50. The SA resource 65 and the data resource 66 may have a second time and / or frequency offset compared to the SA resource 61 and the data resource 62 in the pre-configured initial D2D resource 50. This (these) offsets can be pre-configured. This (these) offsets may be signaled, for example, by the group head of the device-to-device group.

  FIG. 7 illustrates another approach to using a time-frequency resource grid when all UEs in a device-to-device group are out of coverage.

  The D2D resources are dynamically extended to include extended resources 53 in addition to the initially preconfigured D2D resources 50. In the resource use method shown in FIG. 7, the extension resource 53 can be used as a data resource. The scheduling assignment is not transmitted in the extension resource 53, but is kept in the original pre-configured D2D resource 50. The scheduling assignment 61 may provide a link to the extension resource 53, for example, by indicating a subcarrier frequency and / or a symbol 67 of the extension resource 53 used for data transmission.

  The UE according to the embodiment uses the extended resource 53 for SA transmission and data transmission as described with reference to FIG. 6 and only for data transmission as described with reference to FIG. , And the use of the extended resource 53.

  Information about which scheme using extended resources 53 is used may be included in the scheduling assignment. By way of example, whether normal scheduling is performed in which the scheduling assignments are retained in the original pre-configured D2D resource 50, or whether the scheduling assignments may be included in the extension resources 53 may be extended scheduling. Whether it is implemented may be indicated by one information bit or multiple information bits. For example, in response to receiving such a scheduling assignment from the group head, UEs 2 and 4 may determine whether further scheduling assignments are received only on the original pre-configured D2D resource 50, or It can be determined whether or not it can be included in the extended resource 53 as well.

  FIG. 8 is a flowchart of a method 80 according to one embodiment. Method 80 may be performed by user equipment according to one embodiment.

  At 81, the user equipment may use pre-configured D2D resources to perform D2D discovery and / or D2D communication. User equipment may be in coverage while using pre-configured D2D resources to perform D2D discovery and / or D2D communication.

  At 82, the user equipment may determine whether criteria for enabling use of the extended resources in addition to the pre-configured D2D resources to perform D2D discovery and / or D2D communication are met. . Various techniques may be used to perform the determination at. The user equipment may monitor whether all other user equipment included in the same device-to-device group is outside the coverage of the cellular communication network. The user equipment may evaluate its own SINR or other quality indicator for network quality to determine whether the use of extended resources to perform D2D discovery and / or D2D communication may be enabled. The user equipment evaluates the SINR or other quality indicator for network quality reported to the user equipment by other user equipment, for example, other user equipment in the same group, and performs D2D discovery and / or D2D communication. May be enabled if the use of the extended resources for can be enabled. The user equipment may evaluate whether any suitable cells around the user equipment may cause interference. The user equipment may monitor the signaling from the group head of the device-to-device group to determine whether use of the extended resource is selectively enabled. The user equipment may evaluate one or several predefined geolocation constraints based on its location. If the criteria are not met, the user equipment may continue to use only the pre-configured D2D resources at 81.

  If the criteria for using extended resources for D2D discovery and / or D2D communication are met, the user equipment may begin using the extended resources for D2D discovery and / or D2D communication at 83. The user equipment may determine whether the scheduling assignment can also be included in the resource extension based on, for example, the scheduling assignment received from the group head. The user equipment may selectively monitor the extension resources for the scheduling assignment, depending on whether the scheduling assignment can also be included in the resource extension. Data may be derived from subcarrier frequencies and symbols on either the original pre-configured D2D resources or the extension resources, as specified by the scheduling assignment.

  At 84, the user equipment may determine whether criteria for using the extended resources in addition to the pre-configured D2D resources to perform D2D discovery and / or D2D communication are still met. This may be implemented in any one of the approaches described with reference to 82. By way of example, a user equipment may monitor whether any one of the other user equipments in the device-to-device group moves into coverage. The user equipment may listen for signaling from the group head of the device-to-device group and determine whether the use of the extended resource is disabled. The user equipment may monitor whether the user equipment itself moves into coverage. If the criteria are not met, the user equipment may again use only pre-configured D2D resources at 81 for D2D discovery and / or D2D communication.

  If the criteria for using the extended resources are still met, the user equipment may continue to use the extended D2D resources at 85, including both the original pre-configured D2D resources and the extended resources.

  FIG. 9 is a flowchart of a method 90 according to one embodiment. Method 90 may be performed by user equipment according to one embodiment. User equipment may be included in a device-to-device group. A device-to-device group may include multiple devices capable of performing D2D communication with each other. Method 90 may be performed by user equipment that does not act as a group head of a device-to-device group, or may be performed by user equipment that acts as a group head. Devices in a device-to-device group may use the same wireless interface to implement D2D communication with each other and for communication with a cellular communication network.

  At 91, the user equipment may monitor which devices of the device-to-device group are within the coverage of the cellular communication network and which devices of the device-to-device group are outside the coverage of the cellular communication network. All devices in the device-to-device group may broadcast information about whether they are in-coverage or out-of-coverage. Alternatively, all devices in the device-to-device group may implement one-to-one signaling to report information to the group head about whether they are in-coverage or out-of-coverage. The information may include a signal quality indicator, for example, the SINR measured by each device in the device-to-device group.

  At 92, the user equipment may determine whether all devices of the device-to-device group are out of coverage of the cellular communication network. If even at least one device is not out of coverage, monitoring may continue at 91.

  If all devices in the device-to-device group are outside the coverage of the cellular communication network, at 93, the use of the extended resources is enabled. Extended resources may be used as scheduling assignment resources and data resources. Extended resources may only be used as data resources, with the scheduling assignment still contained within the original pre-configured D2D resource.

  At 94, the user equipment may determine whether at least one device of the device-to-device group has returned within the coverage of the cellular communication network.

  If none of the devices in the device-to-device group has returned within the coverage of the cellular communication network, the extended resources may continue to be used at 95 as data resources and, optionally, as SA resources. The method may return to 94.

  If at least one device of the device-to-device group returns within the coverage of the cellular communication network, use of extended resources for D2D discovery and / or D2D communication may be disabled at 96. All scheduling assignment transmissions and data transmissions are performed using only the original pre-configured D2D resources.

  Various techniques may be used by the user equipment to dynamically adjust device-to-device resources. Exemplary implementations are described in more detail with reference to the signaling diagrams of FIGS.

  FIG. 10 is a diagram illustrating signaling used to control device-to-device resources for D2D discovery and / or D2D communication. A user equipment (UE) performs D2D signaling with another UE acting as a group head.

  The UE sends out-of-coverage information 91 in response to detecting that the UE is out of coverage or moves out of coverage. Out-of-coverage information 91 may be sent over the same interface configured for communication with the RAN. Out-of-coverage information 91 may be sent directly to the group head. The out-of-coverage information 91 can be transmitted as a one-to-one message.

  The UE receives a message 92 from the group head if all other devices in the device-to-device group are also out of coverage. The message 92 enables the use of extended resources for D2D discovery and / or D2D communication. The message 92 may be selectively generated by the group head when all devices in the device-to-device group are out of coverage or move out of coverage. The out-of-coverage information 91 can be transmitted as a one-to-one message. Message 92 may be broadcast to a device-to-device group. Message 92 may be a one-to-one message.

  The UE transmits the in-coverage information 93 in response to detecting that the UE is in the coverage or moves in the coverage. In-coverage information 93 may be sent over the same interface configured for communication with the RAN. The in-coverage information 93 can be sent directly to the group head. The in-coverage information 93 can be transmitted as a one-to-one message.

  Receipt of the in-coverage information 93 triggers the group head to terminate the use of extended resources for D2D communication and / or D2D discovery for the entire device-to-device group. The group head may broadcast another message 94 to the device-to-device group to disable the use of extended resources for D2D communication and / or D2D discovery.

  Although the in-coverage events for the UE are illustrated in FIG. 10, the use of extended resources for D2D communication and / or D2D discovery depends on whether any other device of the device-to-device group is in the cellular communication network. Moving into coverage also ends.

  FIG. 10 is a diagram illustrating signaling used to control device-to-device resources for D2D discovery and / or D2D communication. The user equipment (UE) implements D2D signaling with other UEs, denoted UE B and UE C in FIG.

  The UE sends out-of-coverage information 101 in response to detecting that the UE is out of coverage or moves out of coverage. Out-of-coverage information 101 may be sent via the same interface configured for communication with the RAN. Out-of-coverage information 101 may be broadcast to all devices in the device-to-device group.

  If all other devices in the device-to-device group are also out of coverage, detecting that the last UE has also moved out of coverage triggers at 102 all devices in the group to D2D Enable the use of extended resources for discovery and / or D2D communication. In this case, no dedicated signaling from the group head is needed. These UEs may themselves monitor whether all UEs in the group are out of coverage.

  The UE transmits the in-coverage information 103 in response to detecting that the UE is in the coverage or moves in the coverage. The in-coverage information 103 may be sent via the same interface configured for communication with the RAN. Out-of-coverage information 103 may be broadcast to all devices in the device-to-device group.

  If any one of the devices in the device-to-device group moves into the coverage, this may trigger, at 104, all devices in the group to trigger extended resources for D2D discovery and / or D2D communication. Disable use. In this case, no dedicated signaling from the group head is needed. These UEs may themselves detect that at least one of the UEs has moved into the coverage of the cellular communication network.

  User equipment according to embodiments may support services that may be implemented using D2D communication. The set of supported services may be adapted depending on whether extended resources are available for D2D communication. For illustration, voice telephony over D2D communication may be supported even when extended resources are not available for D2D communication. Video telephony or high-definition video telephony may be selectively supported only if extended resources are available for D2D communication, for example, when all devices in the group are out of coverage.

  FIG. 12 is a flowchart of a method 110 according to one embodiment. Method 110 may be performed by user equipment according to one embodiment.

  At 111, a set of services that rely on D2D communication is supported. These services may include low data rate services. At 111, other services with bandwidth or data rate requirements above the threshold criteria may not be supported. High definition video telephony can be an example for such services with high bandwidth requirements.

  At 112, it is determined whether the use of the extended resources for D2D communication is enabled. If the use of extended resources is not enabled for D2D communication, the method may return to state 111.

  If the use of extended resources for D2D communication is enabled, at 113, the set of supported services may be adapted. The set of supported services may include other services. By way of example, the set of services for execution may include other services that have bandwidth or data rate requirements that exceed a threshold criterion. At 113, the adapted set may include video telephony. At 113, the adapted set may include high definition video telephony.

  At 114, it is determined whether the use of extended resources for D2D communication has been enabled. If the use of extended resources has not been disabled for D2D communication, the adapted set of services may still be supported at 115. The method may return to monitoring 114. If the use of extended resources has been disabled for D2D communication, the method may return to 111. In this case, the extended resources are once again separated from D2D discovery and D2D communication to mitigate the risk of interference with the RAN.

  FIG. 13 is a block diagram 120 of a user device according to one embodiment. These modules may be implemented in hardware, software, firmware, or a combination thereof.

  The user equipment may include a processing module 121 for processing the received signal. The processing module 121 may be configured to process both signals from the cellular communication network and signals received in D2D discovery and / or D2D communication from other user equipment.

  The user equipment may include a monitoring module 122 that monitors whether the user equipment is in-coverage or out-of-coverage. The monitoring module may use the SINR or another signal strength indicator for the signal received from the RAN to determine whether the user equipment is in-coverage or out-of-coverage.

  The monitoring module 122 may optionally monitor whether other user equipment in the device-to-device group is in-coverage or out-of-coverage based on the message received at the wireless interface.

  The user equipment may include a reporting module 123. A reporting module may be coupled to the wireless interface control 125 to cause transmission of the report at least when the user equipment moves from within coverage to out of coverage and when the user equipment moves from outside coverage to inside coverage. .

  The user equipment may include a control module 124 for controlling resources on which D2D discovery and / or D2D communication is performed. The control module 124 adapts the resources on which D2D discovery and / or D2D communication is performed, depending on whether the user equipment and optionally other user equipment in the same group are out of coverage. It can be configured as follows. The control module 124 may enable the use of extended resources for D2D discovery and / or D2D communication when all user equipment in the group is out of coverage. The control module 124 may disable the use of extended resources for D2D discovery and / or D2D communication when at least one user equipment of the group is in coverage.

  The user equipment may include a management module 126 for managing supported services utilizing D2D communication. The management module 126 may provide a list of supported services that may be performed when the extended D2D resources are available, for example, because the user equipment and other user equipment in the same group are out of coverage. Additional services may be included in the set.

  In any one of the devices, systems, and methods disclosed herein, a criterion for triggering expansion of D2D resources that depends on a signal quality indicator may be utilized. For illustration, the SINR may be compared to a threshold to determine whether the extended resources can be used for D2D discovery and / or D2D communication.

  Various thresholds may be used when determining whether D2D resources can be extended and when determining whether the UE finds a suitable cell. By way of example, to mitigate the problem of interference, the extended resource may only be D2D if the detected network signal strength at the user equipment is lower than the signal strength at which the user equipment would identify a suitable cell. It may be selectively enabled for discovery and / or D2D communication.

  FIG. 14 illustrates the operation of the user equipment according to one embodiment. A signal quality indicator, eg, SINR, may be compared to at least one threshold to determine whether the extended resources can be used for D2D discovery and / or D2D communication. The signal quality indicator may be compared to an activation threshold TH_er for the extension resource. For some user equipment in the group, the extended resources that can be used for D2D discovery and / or D2D communication only if the signal quality indicator is within the range 131 that is less than the activation threshold TH_er Use is enabled.

  The activation threshold TH_er may be smaller than the threshold TH_ic at which the user equipment finds a suitable cell to camp on. In the value range 132 of the signal quality indicator, the use of extended resources that may be used for D2D discovery and / or D2D communication has been disabled, and the user equipment has not yet found a suitable cell to camp on. Absent.

  In any one of the various embodiments, the D2D discovery and / or D2D communication may include sending and / or receiving messages over the same interface where the UE communicates with the RAN.

  In other embodiments, modifications or changes may be implemented. For illustration, the resources may not only be pre-configured at the UE, directly by the base station, but also by another UE acting as a group head for the D2D communication group, or by a repeater relay.

  For further illustration, some embodiments are described in the context of D2D communication, but these techniques are also applicable to D2D discovery.

  In an exemplary embodiment, if at least two user equipments in the group move out of coverage, the D2D resources may be expanded by adding expansion resources to the pre-configured D2D resources. At least two user equipments may form an isolated user group (IUG).

  In any one of the embodiments, information about the in-coverage state or the out-of-coverage state of the user equipment may be included in the SA content or the data content.

  The message sent by the group head to enable or disable the use of extended resources for D2D discovery and / or D2D communication is in the group head's SA content, or in the group head's data content, or It may be included in D2DSS (D2D synchronization source) or in PD2DSCH content.

Embodiments of the present invention allow for dynamically adjusting the resources available for D2D discovery and / or D2D communication. Interference with the RAN communication may be suppressed or prevented.

Claims (15)

User equipment,
A wireless interface (20) configured for communication with a cellular communication network;
A processing device (24) configured to control the wireless interface (20) to use device-to-device resources (50, 53) for device-to-device discovery and / or device-to-device communication;
With
The user equipment (2) uses a pre-configured resource (50) when the user equipment (2) is within the coverage of the cellular communication network, and the user equipment (2) If it is out of network coverage, use pre-configured resources (50) and additional extended resources (53),
When all devices (2,3,4) of the device-to-device group including the user equipment (2) move out of the coverage of the cellular communication network or exist outside the coverage of the cellular communication network, The use of the extended resource (53) for the device-to-device discovery and / or the device-to-device communication is enabled;
The use of the extended resource (53) is selectively performed according to a signal-to-noise-plus-interference ratio (SINR) measured by all devices of the device-to-device group, wherein the extended resource (53) comprises: User equipment that is used only if each said device is below a threshold, said threshold being less than a further threshold of said SINR that determines whether said device is within said coverage . The device-to-device discovery, when at least one device (2,3,4) of the device-to-device group moves within the coverage of the cellular communication network or is present in the coverage of the cellular communication network; / Or the use of the extended resource (53) for the device-to-device communication is disabled;
The user equipment according to claim 1 . The user equipment (2) controls the wireless interface (20) to indicate that the user equipment (2) has moved out of the coverage of the cellular communication network, or that the user equipment (2) has Transmitting information (91; 101) indicating that it is outside the coverage of the network;
User equipment according to claim 1 or 2. The user equipment (2) is configured to receive a message (92) at the wireless interface (20) in response to the information (91), wherein the message (92) is transmitted by the user equipment (2). Enabling the use of the extended resources (53) for the device-to-device discovery and / or the device-to-device communication;
The user equipment according to claim 3 . The user equipment (2) determines whether the use of the extended resource (53) for the device-to-device discovery and / or the device-to-device communication causes interference with a radio access network of the cellular communication network. Is configured to determine
The user equipment according to any one of claims 1 to 4 . The user equipment (2) is configured to determine whether a positioning of the user equipment (2) satisfies a geolocation constraint;
The use of the extended resources (53) for the device-to-device discovery and / or the device-to-device communication is enabled depending on whether the positioning satisfies the geolocation constraints,
User equipment according to any one of claims 1 to 5. The user equipment (2) may communicate with the cellular communication network if the use of the extended resource for the device-to-device discovery and / or the device-to-device communication is not enabled. Configured to use (53);
User equipment according to any one of claims 1 to 6. The user equipment (2) is configured to use the extended resource (53) as a scheduling assignment resource (63) and as a data resource (64);
User equipment according to any one of claims 1 to 7. The mapping between the scheduling assignment resource (63) in the extension resource (53) and the data resource (64) is performed by scheduling assignment resource in a device-to-device resource (50) pre-configured by the cellular communication network. Depending on the mapping between (61) and the data resource (62),
A user device according to claim 8 . The user equipment (2) is configured to use the extended resource (53) as a data resource (65) and use the pre-configured resource (50) as a scheduling assignment resource (61);
User equipment according to any one of claims 1 to 9. The user equipment (2) may, depending on whether the use of the extended resource (53) for the device-to-device discovery and / or the device-to-device communication is enabled, provide at least one service. Configured to trigger execution,
User equipment according to any one of claims 1 to 10. A communication system,
A device-to-device group comprising a plurality of devices (2,3,4) configured for communication with a cellular communication network, wherein each device (2,3,4) of said device-to-device group comprises a device-to-device group. Further configured for device discovery and device-to-device communication,
At least one device (2) of the device-to-device group is configured as a user equipment according to any one of claims 1 to 11 ,
The device to device group includes a group head (3), wherein the group head (3) comprises:
Determining whether all devices (2,3,4) of the device-to-device group move out of the coverage of the cellular communication network or are out of the coverage of the cellular communication network;
Selectively enabling the plurality of devices (2, 3, 4) to use extended resources (53) for the device-to-device discovery and / or the device-to-device communication;
A communication system configured as follows. The group head (3) is provided when at least one device (2,3,4) of the device-to-device group moves within the coverage of the cellular communication network or is present in the coverage of the cellular communication network. Further configured to disable the use of the extended resource (53) for the device-to-device discovery and / or the device-to-device communication;
The communication system according to claim 12 . A method for controlling a user equipment (2), said user equipment (2) comprising a wireless interface (20) configured for communication with a cellular communication network, the method comprising:
Determining if the user equipment (2) moves out of or is out of coverage of the cellular communication network;
Using device-to-device resources (50, 53) for device-to-device discovery and / or device-to-device communication through the wireless interface (20);
Including
Pre-configured resources (50) for device-to-device discovery and / or device-to-device communication are used when the user equipment (2) is within the coverage of the cellular communication network;
The pre-configured resources (50) and additional extended resources (53) for device-to-device discovery and / or device-to-device communication are such that the user equipment (2) is outside the coverage of the cellular communication network Used when
When all devices (2,3,4) of the device to device group including the user equipment (2) move out of the coverage of the cellular communication network or exist outside the coverage of the cellular communication network, The use of the extended resource (53) for the device-to-device discovery and / or the device-to-device communication is enabled;
The use of the extended resource (53) is selectively performed according to a signal-to-noise-plus-interference ratio (SINR) measured by all devices of the device-to-device group, wherein the extended resource (53) comprises: The method, used only if each of the devices is below a threshold, wherein the threshold is less than a further threshold of the SINR that determines whether the device is within the coverage . Wherein according to any one of claims 1 to 11 is performed by the user equipment (2),
The method according to claim 14 .

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