Method for maintaining direct device-to-device communication in wireless access system supporting device-to-device communication and apparatus for supporting same
The present invention discloses methods for maintaining direct device-to-device communication when one device from devices that are in direct device-to-device communication performs a handover, and apparatuses for supporting same. A method for maintaining the direct device-to-device communication in the wireless access system, according to one embodiment of the present invention, comprises the steps of: a second device moving to a second base station of a target cell; and the second device receiving from a first device of serving cell resource allocation information on a newly allocated resource region for direct device-to-device communication, wherein the resource allocation information can be received through an existing device-to-device link (D2D link), which is formed for direct device-to-device communication between the second device and the first device.
1. A method for maintaining device-to-device (D2D) direct communication in a wireless access system that supports D2D direct communication, the method performed by a second device and comprising:
moving to a second base station of a target cell; and
receiving, from a first device of a serving cell, resource allocation information on a newly allocated resource region for the D2D direct communication in the target cell,
wherein the resource allocation information is received through an existing D2D link, which is configured for D2D direct communication between the second device and the first device.
2. The method according to claim 1 , further comprising: transmitting, from the first base station of the serving, one or more of resource information on the existing D2D link and information on the second device to the second base station.
3. The method according to claim 2 , further comprising:
transmitting, from the second base station, the resource allocation information to the first base station of the serving cell through a backhaul link; and
the first base station transmitting the resource allocation information to the first device.
4. The method according to claim 3 , wherein the D2D direct communication between the second device and the first device is performed through the resource region indicated by the resource allocation information, after the second device moves to the second cell.
5. A method for maintaining device-to-device (D2D) direct communication in a wireless access system that supports D2D direct communication, the method performed by a first base station and comprising:
transmitting resource information on resources used for the D2D direct communication to a second base station;
receiving resource allocation information which is newly allocated for the D2D direct communication from a second cell controlled by the second base station, from the second base station; and
transmitting the resource allocation information to a first device,
wherein the resource allocation information is transmitted to a second device which performs handover to the second base station, through an existing D2D link where D2D direct communication is performed between devices.
6. The method according to claim 5 , wherein the first base station and the second base station transmit and receive the resource information and the resource allocation information through a backhaul link.
7. A second device for maintaining device-to-device (D2D) direct communication in a wireless access system that supports D2D direct communication, the second device comprising:
a receiver; and
a processor configured to maintain the D2D direct communication,
wherein the second device moves to a second base station of a target cell and receives from a first device of a serving cell resource allocation information on a newly allocated resource region for the D2D direct communication in the target cell, through the receiver, and
the resource allocation information is received through an existing D2D link, which is configured for D2D direct communication between the second device and the first device.
8. The second device according to claim 7 , wherein the first base station of the serving cell transmits one or more of resource information on the existing D2D link and information on the second device to the second base station.
9. The second device according to claim 8 , wherein the second base station transmits the resource allocation information to the first base station of the serving cell through a backhaul link, and the first base station transmits the resource allocation information to the first device.
10. The second device according to claim 9 , wherein the D2D direct communication between the second device and the first device is performed through the resource region indicated by the resource allocation information after the second device moves to the second cell.