SYSTEM AND METHOD TO REDUCE RADIO RESOURCE MANAGEMENT (RRM) RELATED SIGNALING IN MACHINE-TO-MACHINE (M2M) COMMUNICATIONS

• US 20140313908A1
• Filed: 04/17/2013
• Published: 10/23/2014
• Est. Priority Date: 04/17/2013
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Dimou, Konstantinos, da Silva, Icaro L. J.
• Granted Patent: US 9,661,441 B2
• Time in Patent Office: Days
• US Class Current: 370/252
• CPC Class Codes: H04W 4/70 Services for machine-to-machine communication [M2M] or machine type communication [MTC]
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

System and method for reducing signaling overhead related to scheduling of uplink and downlink radio resources to wireless devices (e.g., sensors or Machine-to-Machine (M2M) devices) that are primarily stationary in a cellular network. Because these wireless devices are non-moving, time-frequency channel conditions have a much lower variance for them as compared to other mobile devices in the network. Hence, the (semi)stationary channel can be estimated over time with the help of statistical methods and machine learning techniques, and stationary devices can be then instructed to stop reporting uplink and/or downlink channel condition related information to the network until further notice. When performance degradation is noticed by the base station, the scheduler may instruct the device to resume its channel condition reporting. As a byproduct of this solution, the energy consumed within such stationary terminals is reduced due to significant reductions in the number of channel measurements, their processing, and reporting.

Claims

1. A method for reducing signaling overhead related to scheduling of Uplink (UL) and Downlink (DL) radio resources to a wireless device that is in wireless communication with a network entity in a mobile communication network associated with the wireless device, wherein the mobile communication network receives UL and DL scheduling information from the network entity, the method comprising performing the following using the network entity:

upon detecting that the wireless device is stationary, performing at least one of the following;

statistically analyzing DL channel condition related information received from the wireless device over a first predetermined time interval to determine device-specific DL scheduling resources to allocate to the wireless device; and

statistically analyzing UL channel condition related information received from the wireless device over a second predetermined time interval to determine device-specific UL scheduling resources to allocate to the wireless device; and

upon conclusion of statistical analysis, instructing the wireless device to perform at least one of the following;

stop reporting DL channel condition related information to the network entity until further notice; and

stop reporting UL channel condition related information to the network entity until further notice.

2. The method of claim 1, wherein the network entity is one of the following:

a Radio Base Station (RBS);

a Base Station Controller (BSC);

an evolved Node B (eNodeB); and

a mobile communication node comprising UL and DL schedulers.

3. The method of claim 1, wherein the wireless device is one of the following:

a Machine-to-Machine (M2M) Device;

an M2M Gateway; and

a User Equipment (UE).

4. The method of claim 1, wherein the DL channel condition related information includes at least one of the following:

an estimation of complex channel values per sub-band over a first predetermined number of frequency sub-bands associated with a DL reference signal sent by the network entity and received by the wireless device over a wireless communication channel; and

a distribution of Channel Quality Information (CQI) for the wireless communication channel over a second predetermined number of frequency sub-bands associated with the DL reference signal;

wherein the UL channel condition related information includes a Sounding Reference Signal (SRS).

5. The method of claim 1, wherein statistically analyzing DL channel condition related information includes:

generating device-specific DL-related stored information over the first predetermined time interval, wherein the device-specific DL-related stored information is generated by storing the following using a unique identity for the wireless device;

all DL channel condition related information received from the wireless device over the first predetermined time interval; and

network state related information for a state of the mobile communication network at a time of receipt of the DL channel condition related information over the first predetermined time interval;

analyzing the device-specific DL-related stored information to determine therefrom future DL scheduling resources for the wireless device in case of absence of further DL channel condition related information from the wireless device; and

preparing a first indicator that enables the wireless device to stop reporting DL channel condition related information to the network entity; and

wherein statistically analyzing UL channel condition related information includes;

estimating UL channel quality for each UL channel condition related information received from the wireless device over the second predetermined time interval;

generating device-specific UL-related stored information over the second predetermined time interval, wherein the device-specific UL-related stored information is generated by storing the following using the unique identity for the wireless device;

all UL channel condition related information received from the wireless device over the second predetermined time interval;

estimations of UL channel quality associated with the UL channel condition related information; and

network state related information for a state of the mobile communication network at the time of estimations of UL channel quality;

analyzing the device-specific UL-related stored information to determine therefrom future UL scheduling resources to allocate to the wireless device in case of absence of further UL channel condition related information from the wireless device; and

preparing a second indicator that enables the wireless device to stop reporting UL channel condition related information to the network entity.

6. The method of claim 5, wherein instructing the wireless device to stop reporting DL channel condition related information includes sending the first indicator with a first predetermined value to the wireless device, and wherein instructing the wireless device to stop reporting UL channel condition related information includes sending the second indicator with a second predetermined value to the wireless device.

7. The method of claim 6, wherein at least one of the first and the second indicators is one of the following:

a first flag bit in a Downlink Control Information (DCI) message sent to the wireless device via a first Physical Downlink Control Channel (PDCCH); and

a second flag bit in a Radio Resource Control (RRC) message sent to the wireless device via a second PDCCH.

8. The method of claim 6, further comprising performing at least one of the following using the network entity:

instructing the wireless device to resume reporting DL channel condition related information to the network entity; and

instructing the wireless device to resume reporting UL channel condition related information to the network entity.

9. The method of claim 8, wherein instructing the wireless device to resume reporting DL channel condition related information includes sending the first indicator with a third predetermined value to the wireless device, and wherein instructing the wireless device to resume reporting UL channel condition related information includes sending the second indicator with a fourth predetermined value to the wireless device.

10. The method of claim 9, wherein the third predetermined value is opposite of the first predetermined value, and wherein the fourth predetermined value is opposite of the second predetermined value.

11. The method of claim 1, wherein at least one of the following applies:

the first predetermined time interval is measured in terms of a time taken to receive a first predetermined number of reports from the wireless device, wherein each report in the first predetermined number of reports contains a report-specific DL channel condition related information; and

the second predetermined time interval is measured in terms of a time taken to receive a second predetermined number of reports from the wireless device, wherein each report in the second predetermined number of reports contains a report-specific UL channel condition related information.

12. A mobile communication node configured to provide a radio interface to a wireless device in a wireless network associated with the wireless device, wherein the mobile communication node comprises:

a transceiver configured to transmit wireless signals to the wireless device and to receive wireless signals from the wireless device;

a scheduler configured to send Uplink (UL) and Downlink (DL) radio resource scheduling information to the wireless device via the transceiver, and receive DL and UL channel condition related information from the wireless device via the transceiver; and

a processor coupled to the transceiver and the scheduler, and configured to perform at least one of the following upon detecting that the wireless device is stationary;

statistically analyze DL channel condition related information received by the scheduler from the wireless device over a first predetermined time interval to determine device-specific DL scheduling resources to allocate to the wireless device; and

statistically analyze UL channel condition related information received by the scheduler from the wireless device over a second predetermined time interval to determine device-specific UL scheduling resources to allocate to the wireless device;

wherein the processor is further configured to provide the scheduler with results of statistical analysis; and

wherein, upon receiving the results of statistical analysis from the processor, the scheduler is operable to send an instruction to the wireless device via the transceiver, wherein the instruction instructs the wireless device to perform at least one of the following;

stop reporting DL channel condition related information to the mobile communication node until further notice; and

stop reporting UL channel condition related information to the mobile communication node until further notice.

13. The mobile communication node of claim 12, further comprising:

a memory coupled to the processor and the scheduler;

wherein the scheduler is configured to store device-specific DL-related information in the memory using a unique identity for the wireless device, wherein the device-specific DL-related information includes;

all DL channel condition related information received from the wireless device over the first predetermined time interval; and

network state related information for a state of the wireless network at a time of receipt of the DL channel condition related information over the first predetermined time interval; and

wherein the processor is configured to statistically analyze DL channel condition related information by performing the following;

analyzing the device-specific DL-related information stored in the memory to determine therefrom future DL scheduling resources to allocate to the wireless device in case of absence of further DL channel condition related information from the wireless device; and

preparing a first command to be sent to the scheduler as part of the results of statistical analysis to enable the scheduler to instruct the wireless device to stop reporting DL channel condition related information to the mobile communication node.

14. The mobile communication node of claim 13, wherein the scheduler is further configured to:

estimate UL channel quality for each UL channel condition related information received from the wireless device over the second predetermined time interval; and

store device-specific UL-related information in the memory using the unique identity for the wireless device, wherein the device-specific UL-related information includes;

all UL channel condition related information received from the wireless device over the second predetermined time interval;

estimations of UL channel quality associated with the UL channel condition related information; and

network state related information for a state of the wireless network at a time of estimations of UL channel quality; and

wherein the processor is further configured to statistically analyze UL channel condition related information by performing the following;

analyzing the device-specific UL-related information stored in the memory to determine therefrom future UL scheduling resources to allocate to the wireless device in case of absence of further UL channel condition related information from the wireless device; and

preparing a second command to be sent to the scheduler as part of the results of statistical analysis to enable the scheduler to instruct the wireless device to stop reporting UL channel condition related information to the mobile communication node.

15. The mobile communication node of claim 14, wherein, in response to receiving the first command from the processor, the scheduler is configured to send a first message with a first predetermined value to the wireless device as part of instructing the wireless device to stop reporting DL channel condition related information, and

wherein, in response to receiving the second command from the processor, the scheduler is further configured to send a second message with a second predetermined value to the wireless device as part of instructing the wireless device to stop reporting UL channel condition related information.

16. The mobile communication node of claim 12, wherein the mobile communication node is one of the following:

a Radio Base Station (RBS);

a Base Station Controller (BSC); and

an evolved Node B (eNodeB).

17. A method for reducing signaling overhead related to scheduling of Uplink (UL) and Downlink (DL) radio resources to a wireless device that is in wireless communication with a network entity in a mobile communication network associated with the wireless device, the method comprises performing the following using the wireless device:

reporting at least one of the following to the network entity;

DL channel condition related information; and

UL channel condition related information;

monitoring a DL control channel that provides UL and DL radio resource scheduling information from the network entity;

identifying whether the DL control channel includes one of the following device-specific indicators for the wireless device;

a first indicator with a first predetermined value; and

a second indicator with a second predetermined value;

discontinuing the reporting of DL channel condition related information to the network entity when the wireless device receives the first indicator with the first predetermined value from the DL control channel; and

discontinuing the reporting of UL channel condition related information to the network entity when the wireless device receives the second indicator with the second predetermined value from the DL control channel.

18. The method of claim 17, wherein discontinuing the reporting of DL channel condition related information includes the following:

continuing to use the same DL scheduling grant as that was used by the wireless device immediately prior to the receipt of the first indicator;

and wherein discontinuing the reporting of UL channel condition related information includes the following;

continuing to use the same UL scheduling grant as that was used by the wireless device immediately prior to the receipt of the second indicator.

19. The method of claim 17, further comprising performing the following using the wireless device:

further monitoring the DL control channel to identify whether the DL control channel includes one of the following device-specific indicators for the wireless device;

the first indicator with a third predetermined value; and

the second indicator with a fourth predetermined value;

resuming the reporting of DL channel condition related information to the network entity when the wireless device receives the first indicator with the third predetermined value from the DL control channel; and

resuming the reporting of UL channel condition related information to the network entity when the wireless device receives the second indicator with the fourth predetermined value from the DL control channel.

20. A wireless device that is in wireless communication with a network entity in a mobile communication network associated with the wireless device, wherein the wireless device comprises:

a transceiver configured to transmit wireless signals to and receive wireless signals from the network entity; and

a processor coupled to the transceiver and configured to perform the following;

report at least one of the following to the network entity using the transceiver;

Downlink (DL) channel condition related information; and

Uplink (UL) channel condition related information;

monitor, using the transceiver, a DL control channel that provides UL and DL radio resource scheduling information from the network entity;

identify whether the DL control channel includes one of the following device-specific indicators for the wireless device;

a first indicator with a first predetermined value; and

a second indicator with a second predetermined value;

discontinue the reporting of DL channel condition related information to the network entity when the processor receives, via the transceiver, the first indicator with the first predetermined value from the DL control channel; and

discontinue the reporting of UL channel condition related information to the network entity when the processor receives, via the transceiver, the second indicator with the second predetermined value from the DL control channel.

21. The wireless device of claim 20, wherein the wireless device is one of the following:

a Machine-to-Machine (M2M) Device;

an M2M Gateway; and

a User Equipment (UE).

22. The wireless device of claim 20, wherein the processor is further configured to perform at least one of the following:

continue to use a DL scheduling grant that was used by the wireless device immediately prior to the receipt of the first indicator; and

continue to use a UL scheduling grant that was used by the wireless device immediately prior to the receipt of the second indicator.

23. A system for reducing signaling overhead related to scheduling of Uplink (UL) and Downlink (DL) radio resources in a mobile communication network, the system comprising:

a wireless device that is in wireless communication with a mobile communication node in the mobile communication network, wherein the wireless device is configured to perform the following;

report at least one of the following to the mobile communication node;

DL channel condition related information; and

UL channel condition related information;

monitor a DL control channel that provides UL and DL radio resource scheduling information from the mobile communication node;

identify whether the DL control channel includes one of the following device-specific indicators for the wireless device;

a first indicator with a first predetermined value; and

a second indicator with a second predetermined value;

discontinue the reporting of DL channel condition related information to the mobile communication node when the wireless device receives the first indicator with the first predetermined value from the DL control channel; and

discontinue the reporting of UL channel condition related information to the mobile communication node when the wireless device receives the second indicator with the second predetermined value from the DL control channel; and

the mobile communication node for providing a radio interface to the wireless device in the mobile communication network, wherein the mobile communication node is configured to perform the following;

send DL and UL radio resource scheduling information to the wireless device and receive DL and UL channel condition related information from the wireless device;

upon detecting that the wireless device is stationary, perform at least one of the following;

statistically analyze DL channel condition related information received from the wireless device over a first predetermined time interval to determine device-specific DL scheduling resources to allocate to the wireless device; and

statistically analyze UL channel condition related information received from the wireless device over a second predetermined time interval to determine device-specific UL scheduling resources to allocate to the wireless device; and

upon conclusion of statistical analysis, send the DL control channel with the first indicator or the second indicator to the wireless device, thereby instructing the wireless device to perform one of the following;

stop reporting DL channel condition related information to the mobile communication node until further notice when the DL control channel contains the first indicator; and

stop reporting UL channel condition related information to the mobile communication node until further notice when the DL control channel contains the second indicator.

24. A mobile communication node configured to provide a radio interface to a wireless device in a wireless network associated with the wireless device, wherein the mobile communication node is configured to perform the following:

receive Downlink (DL) and Uplink (UL) channel condition related information from the wireless device;

upon detecting that the wireless device is stationary, perform at least one of the following;

statistically analyze DL channel condition related information received from the wireless device over a first predetermined time interval to determine device-specific DL scheduling resources to allocate to the wireless device; and

statistically analyze UL channel condition related information received from the wireless device over a second predetermined time interval to determine device-specific UL scheduling resources to allocate to the wireless device;

upon conclusion of statistical analysis, send a Downlink Control Information (DCI) message to the wireless device instructing the wireless device to perform one of the following;

stop reporting DL channel condition related information to the mobile communication node until further notice; and

stop reporting UL channel condition related information to the mobile communication node until further notice.