Apparatus and method for providing device-to-device communication-based service for isolated user equipment in mobile communication system

A first user equipment (UE) for providing a device-to-device (D2D) communication-based service for a second UE, the first UE comprising:

• a transceiver;
• and
• a processor configured to:
• establish a D2D link with the second UE,
• control the transceiver to receive identification information of the first UE via the established D2D link from the first UE, establish a cellular connection for relaying the second UE between the first UE and a network node of the cellular network based on the identification information of the second UE received via the established D2D link, and
• relay data traffic for the second UE via the D2D link and the cellular connection,
• wherein the first UE is within a service coverage area of the network node.

A method for providing a device-to-device (D2D) communication-based service for a first user equipment (UE), the method comprising:

• establishing, by the first UE, a D2D link with a second UE which is within a service coverage area of a network node;
• transmitting identification information of the first UE via the established D2D link to the second UE;
• and
• receiving, by the first UE, data traffic for the first UE via the D2D link and a cellular connection for the first UE,
• wherein the cellular connection for relaying the first UE is established between the second UE and the network node based on identification information of the first UE received via the D2D link, and
• wherein the data traffic for the first UE is relayed by the second UE via the D2D link and the cellular connection.

A first user equipment (UE) for providing a device-to-device (D2D) communication-based service for the first UE, the first UE comprising:

• a transceiver;
• and
• a processor configured to:
• establish, by the first UE, a D2D link with a second UE which is within a service coverage area of a network node,
• control the transceiver to transmit identification information of the first UE via the established D2D link to the second UE, and
• receive data traffic for the first UE via the D2D link and a cellular connection for the first UE,
• wherein the cellular connection for relaying the first UE is established between the second UE and the network node based on identification information of the first UE received via the D2D link, and
• wherein the data traffic for the first UE is relayed by the second UE via the D2D link and the cellular connection.