Method, apparatus and computer program product for controlling device-to-device communication

1 . A method by a first wireless communication device for controlling Device-to-Device, D2D, communication between the first wireless communication device and a second wireless communication device, the method performed by the first wireless communication device and comprising:

transmitting, to the second wireless communication device, a Discontinuous Reception, DRX, configuration for the D2D communication with the second wireless communication device;

applying the DRX configuration for the D2D communication with the second wireless communication device;

starting a DRX validity timer at the first wireless communication device;

based on whether an experienced D2D communication time deviates or does not deviate from an expected D2D communication time by more than a threshold amount during an observation window, changing the DRX validity timer;

receiving, from the second wireless communication device, a notification indicating that the DRX configuration is unsuitable; and

based on the notification, reconfiguring the DRX configuration and/or notifying a network node that the applied DRX configuration is unsuitable.

2 . A first wireless communication device for controlling Device-to-Device, D2D communication between the first wireless communication device and a second wireless communication device, the first wireless communication device comprising:

a memory storing instructions; and

processing circuitry configured to execute the instructions to cause the first wireless communication device to:

transmit, to the second wireless communication device, a Discontinuous Reception, DRX, configuration for the D2D communication with the second wireless communication device;

apply the DRX configuration for the D2D communication with the second wireless communication device;

starting a DRX validity timer at the first wireless communication device;

based on whether an experienced D2D communication time deviates or does not deviate from an expected D2D communication time by more than a threshold amount during an observation window, changing the DRX validity timer;

receive, from the second wireless communication device, a notification indicating that the DRX configuration is unsuitable; and

based on the notification, reconfigure the DRX configuration and/or notifying a network node that the applied DRX configuration is unsuitable.

3 . The first wireless communication device according to claim 2 , wherein the processing circuitry is configured to execute the instructions to cause the first wireless communication device to:

based on the notification that the DRX configuration is unsuitable, stop the applying of the DRX configuration.

4 . The first wireless communication device according to claim 3 , wherein the processing circuitry is configured to execute the instructions to cause the first wireless communication device to perform at least one of:

notify the second wireless communication device that the first wireless communication device has stopped applying the DRX configuration; and

notify the network node that the first wireless communication device has stopped applying the DRX configuration.

5 . The first wireless communication device according to claim 2 , wherein the processing circuitry is configured to execute the instructions to cause the first wireless communication device to:

determine that a validity time associated with the DRX validity timer has expired; and

wherein the DRX validity timer is started in response to at least one of:

transmitting the DRX configuration to the second wireless communication device;

receiving an acknowledgment message from the second wireless communication device; and

determining that a pre-determined time period has lapsed after the DRX configuration is transmitted to the second wireless communication device.

6 . The first wireless communication device according to claim 5 , wherein:

when the experienced D2D communication time deviates from the expected D2D communication time by more than the threshold amount during the observation window, the processing circuitry is configured to execute the instructions to cause the first wireless communication device to change the DRX validity time by resetting the DRX validity timer or shortening the validity time by a certain margin.

7 . The first wireless communication device according to claim 5 , wherein:

when the experienced D2D communication time does not deviate from the expected D2D communication time by more than the threshold amount during the observation window, the processing circuitry is configured to execute the instructions to cause the first wireless communication device to change the DRX validity time by extending a validity time by a certain margin.

8 . The first wireless communication device according to claim 2 , wherein:

reconfiguring the DRX configuration comprises falling back to a default DRX configuration at the first wireless communication device; and

notifying the network node of the falling back to the default DRX configuration.

9 . The first wireless communication device according to claim 8 , wherein falling back to the default DRX configuration comprises:

using the default DRX configuration; and

instructing the second wireless communication device to use the default DRX configuration.

10 . The first wireless communication device according to claim 2 , wherein the processing circuitry is configured to execute the instructions to cause the first wireless communication device to:

transmit the reconfigured DRX configuration to the second wireless communication device.

11 . The first wireless communication device according to claim 2 , wherein the processing circuitry is configured to execute the instructions to cause the first wireless communication device to:

receive, from the network node, the reconfigured DRX configuration to the network node.

12 . The first wireless communication device according to claim 2 , wherein:

the notification from the second wireless communication device comprises at least one of:

a recommended DRX configuration;

at least one parameter for DRX; and

a range of suitable DRX cycles for reconfiguring the DRX configuration at the first wireless communication device; and

the DRX configuration is reconfigured based on at least one of the recommended DRX configuration, the at least one parameter for DRX, and the range of suitable DRX cycles.

13 . The first wireless communication device according to claim 2 , wherein the processing circuitry is configured to execute the instructions to cause the first wireless communication device to transmit, to the network node, at least one of:

the recommended DRX configuration,

the at least one parameter for DRX,

the range of suitable DRX cycles, and

the reconfigured DRX configuration.

14 . The first wireless communication device according to claim 2 , wherein:

the first wireless communication device is receiving the D2D communication from the second wireless device, and

the second wireless communication device is transmitting the D2D communication to the first wireless device.

15 . A second wireless communication device for controlling Device-to-Device, D2D, communication between a first wireless communication device and the second wireless communication device, the second wireless communication device comprising:

a memory storing instructions; and

processing circuitry configured to execute the instructions to cause the first wireless communication device to:

receive, from a first wireless communication device, a Discontinuous Reception, DRX, configuration for the D2D communication with the first wireless communication device;

apply the DRX configuration for the D2D communication with the first wireless communication device;

start a DRX validity timer at the second wireless communication device;

determine that the DRX configuration is unsuitable;

based on whether an experienced D2D communication time deviates or does not deviate from an expected D2D communication time by more than a threshold amount during an observation window, changing the DRX validity timer; and

in response to determining that the DRX configuration is unsuitable, transmit, to the first wireless communication device, a notification indicating that the DRX configuration is unsuitable.

16 . The second wireless communication device according to claim 15 , wherein the processing circuitry is configured to execute the instructions to cause the second wireless communication device to:

in response to determining that the DRX configuration is unsuitable, stop the applying of the DRX configuration.

17 . The second wireless communication device of claim 15 , wherein determining that the DRX configuration is unsuitable comprises:

determining that a validity time associated with the DRX validity timer has expired, and

wherein the DRX validity timer is started in response to at least one of:

receiving the DRX configuration from the first wireless communication device;

transmitting an acknowledgement message to the first wireless communication device after receiving the DRX configuration.

18 . The second wireless communication device according to claim 17 , wherein:

when the experienced D2D communication time deviates from the expected D2D communication time by more than the threshold amount during the observation window, the processing circuitry is configured to execute the instructions to cause the second wireless communication device to change the validity time by resetting the DRX validity timer or shortening the validity time by a certain margin.

19 . The second wireless communication device according to claim 17 , wherein:

when the experienced D2D communication time does not deviate from the expected D2D communication time by more than the threshold amount during the observation window, the processing circuitry is configured to execute the instructions to cause the second wireless communication device change the validity time by extending the validity time by a certain margin.

20 . The second wireless communication device according claim 15 , wherein determining that the DRX configuration is unsuitable comprises:

receiving, from the first wireless communication device, a notification indicating that a validity time of the DRX configuration has expired.

21 . The second wireless communication device according to claim 15 , wherein the processing circuitry is configured to execute the instructions to cause the second wireless communication device to:

receive, from the first wireless communication device, a notification indicating to fall back to a default DRX configuration; and

based on the notification from the first wireless communication device, apply the default DRX configuration.

22 . The second wireless communication device according to claim 21 , wherein the processing circuitry is configured to execute the instructions to cause the second wireless communication device to:

receive, from the first wireless communication device, a reconfigured DRX configuration; and

apply the reconfigured DRX configuration.

23 . The second wireless communication device according to claim 21 , wherein the processing circuitry is configured to execute the instructions to cause the second wireless communication device to transmit, to a network node, at least one of:

a notification that the first wireless communication device and/or the second wireless communication device has fallen back to the default DRX configuration, or

a notification that the first wireless communication device and/or the second wireless communication device is using the reconfigured DRX configuration, or

a message that includes the reconfigured DRX configuration.

24 . The second wireless communication device according to claim 15 , wherein the notification indicating that the DRX configuration is or will be unsuitable comprises at least one of:

a recommended DRX configuration;

at least one associated parameter for DRX; and

a range of suitable DRX cycles for reconfiguring the DRX configuration at the first wireless communication device.

25 . The second wireless communication device according to claim 15 , wherein determining that the DRX configuration is unsuitable comprises at least one of:

determining that the second wireless communication device cannot support the DRX configuration due to mismatch between the DRX configuration and Wide Area Network, WAN, DRX or Uu DRX;

determining that one or multiple new services or flows are being employed on the D2D communication between the first wireless communication device and second wireless communication device; and

determining that a change of transmission power during one or more slots or during a time window is above a threshold amount.

26 . The second wireless communication device according to claim 15 , wherein:

the first wireless communication device is receiving the D2D communication from the second wireless device, and

the second wireless communication device is transmitting the D2D communication to the first wireless device.