Apparatus and method for allocating resources in device-to-device communication in wireless network
A method for allocating resources in Device-to-Device (D2D) communication in a wireless network is provided. The method includes requesting, by a device, resource allocation from an enhanced Node B (eNB) and causing the device to be allocated, from the eNB, a Resource Block (RB) for transmitting one of D2D discovery and communication data and control information. The RB includes information about a location of the resource-allocated time or frequency.
1. A method for requesting resource allocation by a device-to-device (D2D) communication device (D2D device) in a wireless network supporting a D2D communication, the method comprising:
receiving, by the D2D device from a base station, resource pool information including information about one or more resource blocks (RBs) for the D2D communication;
scanning, by the D2D device, an energy level of the one or more RBs included in the resource pool information, the scanned energy level including energy levels of signals received from the one or more RBs;
determining, by the D2D device, to transmit a request for a dynamic resource allocation to the base station, based on whether a result of the scanning of the energy level of the one or more RBs meets a condition for switching a type of resource allocation method to the dynamic resource allocation;
transmitting, by the D2D device to the base station, the request for the dynamic resource allocation; and
receiving, by the D2D device from the base station, a command which instructs the D2D device to stay awake for receiving discovery information from another D2D device,
wherein the command is determined based on a difference between a first time that the base station performs dynamic resource allocation and a second time that the D2D device receives a physical downlink control channel (PDCCH).
2. The method of claim 1 , wherein the condition for switching the type of resource allocation method to the dynamic resource allocation comprises at least one of:
a first case where energy levels of all of the one or more RBs are higher than a specific threshold,
a second case where none of the one or more RBs has an energy level lower than the specific threshold,
a third case where an RB having an energy level lower than the specific threshold exists among the one or more RBs, but a margin between the energy level of the RB having the energy level lower than the specific threshold and the specific threshold is less than a predetermined amount, or
a fourth case where a number of RBs having an energy level lower than the specific threshold among the one or more RBs is less than or equal to a specific number.
3. The method of claim 1 , wherein the condition for switching the type of resource allocation method to the dynamic resource allocation comprises a case where energy levels of all of the one or more RBs are higher than a specific threshold in a process, and the D2D device has a priority greater than or equal to a specific value.
4. The method of claim 1 , wherein the condition for switching the type of resource allocation method to the dynamic resource allocation comprises a case where the D2D device that has a priority greater than or equal to a specific value requires the resource allocation due to a change in an amount of information for the D2D device to transmit.
5. The method of claim 1 , wherein the request for the dynamic resource allocation comprises a request for D2D resources used by the D2D device based on a payload size of the D2D device.
6. The method of claim 1 , wherein the command is received by the D2D device if the difference is less than or equal to a predetermined threshold.
7. The method of claim 1 , wherein the request includes indexes of RBs selected by the D2D device.
8. A method for performing resource allocation by a base station in a wireless network supporting a device-to-device (D2D) communication, the method comprising:
generating, by the base station, resource pool information about one or more resource blocks (RBs) for the D2D communication;
transmitting, by the base station to a D2D device, the resource pool information;
receiving, by the base station from the D2D device, a request for a dynamic resource allocation; and
transmitting, by the base station to the D2D device, a command which instructs the D2D device to stay awake for receiving discovery information from another D2D device,
wherein the D2D device determines to transmit the request for the dynamic resource allocation to the base station, based on whether a result of the D2D device scanning an energy level of the one or more RBs included in the resource pool information meets a condition for switching a type of resource allocation method to the dynamic resource allocation,
wherein the scanned energy level including energy levels of signals received from the one or more RBs, and
wherein the command is determined based on a difference between a first time that the base station performs dynamic resource allocation and a second time that the D2D device receives a physical downlink control channel (PDCCH).
9. The method of claim 8 , wherein the condition for switching the type of resource allocation method to the dynamic resource allocation at least one of:
a first case where energy levels of all of the one or more RBs are higher than a specific threshold,
a second case where none of the one or more RBs has an energy level lower than the specific threshold,
a third case where an RB having an energy level lower than the specific threshold exists among the one or more RBs, but a margin between the energy level of the RB having the energy level lower than the specific threshold and the specific threshold is less than a predetermined amount, or
a fourth case where a number of RBs having an energy level lower than the specific threshold among the one or more RBs is less than or equal to a specific number.
10. The method of claim 8 , wherein the condition for switching the type of resource allocation method to the dynamic resource allocation comprises a case where the energy levels of all of the one or more RBs are higher than a specific threshold in a process, and the D2D device has a priority greater than or equal to a specific value.
11. The method of claim 8 , wherein the condition for switching the type of resource allocation method to the dynamic resource allocation comprises a case where the D2D device that has a priority greater than or equal to a specific value requires the resource allocation due to a change in an amount of information for the D2D device to transmit.
12. The method of claim 8 , wherein the request for the dynamic resource allocation comprises a request for D2D resources used by the D2D device based on a payload size of the D2D device.
13. The method of claim 8 , wherein the command is transmitted if the difference is less than or equal to a predetermined threshold.
14. The method of claim 8 , wherein the request includes indexes of RBs selected by the D2D device.
15. A device-to-device (D2D) communication device (D2D device) in a wireless network supporting a D2D communication, the D2D device comprising:
a transceiver; and
at least one processor configured to:
control the transceiver to receive, from a base station, resource pool information including information about one or more resource blocks (RBs) for the D2D communication,
scan an energy level of the one or more RBs included in the resource pool information, the scanned energy level including energy levels of signals received from the one or more RBs,
determine to transmit a request for a dynamic resource allocation to the base station, based on whether a result of the scanning the energy level of the one or more RBs meets a condition for switching a type of resource allocation method to the dynamic resource allocation,
control the transceiver to transmit the request for the dynamic resource allocation to the base station, and
control the transceiver to receive, from the base station, a command which instructs the D2D device to stay awake for receiving discovery information from another D2D device,
wherein the command is determined based on a difference between a first time that the base station performs dynamic resource allocation and a second time that the D2D device receives a physical downlink control channel (PDCCH).
16. The D2D device of claim 15 , wherein the condition for switching the type of resource allocation method to the dynamic resource allocation comprises at least one of:
a first case where energy levels of all of the one or more RBs are higher than a specific threshold,
a second case where none of the one or more RBs has an energy level lower than the specific threshold,
a third case where an RB having an energy level lower than the specific threshold exists among the one or more RBs, but a margin between the energy level of the RB having the energy level lower than the specific threshold and the specific threshold is less than a predetermined amount, or
a fourth case where a number of RBs having an energy level lower than the specific threshold among the one or more RBs is less than or equal to a specific number.
17. The D2D device of claim 15 , wherein the condition for switching the type of resource allocation method to the dynamic resource allocation comprises a case where energy levels of all of the one or more RBs are higher than a specific threshold in a process, and the D2D device has a priority greater than or equal to a specific value.
18. The D2D device of claim 15 , wherein the condition for switching the type of resource allocation method to the dynamic resource allocation comprises a case where the D2D device that has a priority greater than or equal to a specific value requires the resource allocation due to a change in an amount of information for the D2D device to transmit.
19. The D2D device of claim 15 , wherein the request for the dynamic resource allocation comprises a request for D2D resources used by the D2D device based on a payload size of the D2D device.
20. The D2D device of claim 15 , wherein the command is received if the difference is less than or equal to a predetermined threshold.
21. The D2D device of claim 15 , wherein the request includes indexes of RBs selected by the D2D device.
22. An apparatus configured to perform resource allocation by a base station in a wireless network supporting a device-to-device (D2D) communication, the apparatus comprising:
a transceiver; and
at least one processor configured to:
generate resource pool information about one or more resource blocks (RBs) for the D2D communication,
control the transceiver to transmit the resource pool information to a D2D device,
control the transceiver to receive a request for a dynamic resource allocation from the D2D device, and
control the transceiver to transmit, to the D2D device, a command which instructs the D2D device to stay awake for receiving discovery information from another D2D device,
wherein the D2D device determines to transmit the request for the dynamic resource allocation to the base station, based on whether a result of the D2D device scanning an energy level of the one or more RBs included in the resource pool information meets a condition for switching a type of resource allocation method to the dynamic resource allocation,
wherein the scanned energy level including energy levels of signals received from the one or more RBs, and
wherein the command is determined based on a difference between a first time that the base station performs dynamic resource allocation and a second time that the D2D device receives a physical downlink control channel (PDCCH).
23. The apparatus of claim 22 , wherein the condition for switching the type of resource allocation method to the dynamic resource allocation comprises at least one of:
a first case where energy levels of all of the one or more RBs are higher than a specific threshold,
a second case where none of the RBs has an energy level lower than the specific threshold,
a third case where an RB having an energy level lower than the specific threshold exists among the one or more RBs, but a margin between the energy level of the RB having the energy level lower than the specific threshold and the specific threshold is less than a predetermined amount, or
a fourth case where a number of RBs having an energy level lower than the specific threshold among the one or more RBs is less than or equal to a specific number.
24. The apparatus of claim 22 , wherein condition for switching the type of resource allocation method to the dynamic resource allocation comprises a case where energy levels of all of the one or more RBs are higher than a specific threshold in a process, and the D2D device has a priority greater than or equal to a specific value.
25. The apparatus of claim 22 , wherein the condition for switching the type of resource allocation method to the dynamic resource allocation comprises a case where the D2D device that has a priority greater than or equal to a specific value requires the resource allocation due to a change in an amount of information for the D2D device to transmit.
26. The apparatus of claim 22 , wherein the request for the dynamic resource allocation comprises a request for D2D resources used by the D2D device based on a payload size of the D2D device.
27. The apparatus of claim 22 , wherein the command is transmitted if the difference is less than or equal to a predetermined threshold.
28. The apparatus of claim 22 , wherein the request includes indexes of RBs selected by the D2D device.