MODIFIED ACCESS CLASSES FOR MACHINE TYPE COMMUNICATION (MTC) DEVICES DURING EMERGENCIES

• US 20110270984A1
• Filed: 04/30/2010
• Published: 11/03/2011
• Est. Priority Date: 04/30/2010
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Laboratories of America Incorporated (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Park, Kenneth J.
• Granted Patent: US 8,868,743 B2
• Time in Patent Office: Days
• US Class Current: 709/225
• CPC Class Codes: H04W 4/00 Services specially adapted for wireless communication networks; Facilities therefor
• CPC Class Codes: H04W 4/70 Services for machine-to-machine communication [M2M] or machine type communication [MTC]
• CPC Class Codes: H04W 4/90 Services for handling of emergency or hazardous situations, e.g. earthquake and tsunami warning systems [ETWS]
• CPC Class Codes: H04W 48/06 based on traffic conditions
• CPC Class Codes: H04W 48/08 Access restriction or access information delivery, e.g. discovery data delivery signalling during connection H04W76/00
• CPC Class Codes: H04W 68/00 User notification, e.g. alerting and paging, for incoming communication, change of service or the like
• CPC Class Codes: H04W 74/00 Wireless channel access
• CPC Class Codes: H04W 76/50 for emergency connections

Abstract

A method for determining whether to attempt to attach to a network by a machine type communication (MTC) device is described. A triggering event is detected. A radio frame is received from a base station. The radio frame includes a current access class of the base station. The radio frame is the first radio frame to include the current access class after the triggering event. It is determined if the MTC device has access privileges to the base station. It is then decided whether to attempt to attach to a network based on if the MTC device has access privileges.

Claims

1. A method for determining whether to attempt to attach to a network by a machine type communication (MTC) device, comprising:

detecting a triggering event;

receiving a radio frame from a base station, wherein the radio frame comprises a current access class of the base station, and wherein the radio frame is the first radio frame comprising the current access class after the triggering event;

determining if the MTC device has access privileges to the base station; and

deciding whether to attempt to attach to a network based on if the MTC device has access privileges.

2. The method of claim 1, further comprising determining the current access class of the base station from the radio frame.

3. The method of claim 1, wherein determining if the MTC device has access privileges to the base station comprises comparing an access class of the MTC device with the current access class of the base station, wherein an MTC device has access privileges to the base station if the access class of the MTC device is greater than the current access class of the base station.

4. The method of claim 1, wherein the current access class is in a type 2 system information block (SIB2).

5. The method of claim 1, further comprising abandoning the attempt to attach to the network if the MTC device does not have access privileges.

6. The method of claim 5, further comprising attempting to attach to the network if the MTC device does have access privileges.

7. The method of claim 6, further comprising:

determining a distribution of physical random access channel (PRACH) opportunities to use to attempt to attach to the network; and

selecting one or more PRACH opportunities from the distribution of PRACH opportunities, wherein attempting to attach to the network comprises attempting to attach to the network using the selected one or more PRACH opportunities.

8. The method of claim 7, wherein determining a distribution of PRACH opportunities comprises using a random number generator along with a range value indicating a first and last PRACH opportunity that may be used.

9. The method of claim 7, wherein determining a distribution of PRACH opportunities comprises taking as input a delta-time from when the triggering event was received and when the radio frame was received.

10. The method of claim 7, wherein determining a distribution of PRACH opportunities comprises using a registration number for the MTC device and a range value indicating the possible PRACH opportunities and mapping the registration number across the range value.

11. The method of claim 1, wherein the current access class of the base station is in a data element ac-BarringInfo of a SystemInformationBlockType2 message.

12. The method of claim 11, further comprising examining the data element ac-BarringInfo to determine the current access class of the base station.

13. The method of claim 1, wherein the triggering event requires the MTC device to attempt to attach to the network.

14. An apparatus configured for determining whether to attempt to attach to a network, the apparatus comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory, the instructions being executable to;

detect a triggering event;

receive a radio frame from a base station, wherein the radio frame comprises a current access class of the base station, and wherein the radio frame is the first radio frame to comprise the current access class after the triggering event;

determine if the apparatus has access privileges to the base station; and

decide whether to attempt to attach to a network based on if the apparatus has access privileges.

15. The apparatus of claim 14, wherein the instructions are further executable to determine the current access class of the base station from the radio frame.

16. The apparatus of claim 14, wherein determining if the apparatus has access privileges to the base station comprises comparing an access class of the apparatus with the current access class of the base station, wherein an apparatus has access privileges to the base station if the access class of the apparatus is greater than the current access class of the base station.

17. The apparatus of claim 14, wherein the current access class is in a type 2 system information block (SIB2).

18. The apparatus of claim 14, wherein the instructions are further executable to abandon the attempt to attach to the network if the apparatus does not have access privileges.

19. The apparatus of claim 18, wherein the instructions are further executable to attempt to attach to the network if the apparatus does have access privileges.

20. The apparatus of claim 19, wherein the instructions are further executable to:

determine a distribution of physical random access channel (PRACH) opportunities to use to attempt to attach to the network; and

select one or more PRACH opportunities from the distribution of PRACH opportunities, wherein attempting to attach to the network comprises attempting to attach to the network using the selected one or more PRACH opportunities.

21. The apparatus of claim 20, wherein determining a distribution of PRACH opportunities comprises using a random number generator along with a range value indicating a first and last PRACH opportunity that may be used.

22. The apparatus of claim 20, wherein determining a distribution of PRACH opportunities comprises taking as input a delta-time from when the triggering event was received and when the radio frame was received.

23. The apparatus of claim 20, wherein determining a distribution of PRACH opportunities comprises using a registration number for the apparatus and a range value indicating the possible PRACH opportunities and mapping the registration number across the range value.

24. The apparatus of claim 14, wherein the current access class of the base station is in a data element ac-Barring Info of a SystemInformationBlockType2 message.

25. The apparatus of claim 24, wherein the instructions are further executable to examine the data element ac-BarringInfo to determine the current access class of the base station.

26. The apparatus of claim 14, wherein the triggering event requires the apparatus to attempt to attach to the network.

27. The apparatus of claim 14, wherein the apparatus is a machine type communication (MTC) device.

28. A method for handling emergency events by a base station, the method comprising:

receiving an emergency message;

changing scheduling information and message data;

updating a current access class; and

broadcasting a system information message with the scheduling information and the current access class.

29. The method of claim 28, further comprising sending a paging message to wireless devices indicating the emergency message and a change in scheduling data.

30. The method of claim 28, wherein the scheduling information is broadcast in an SIB1 subframe.

31. The method of claim 28, wherein the current access class is broadcast in an SIB2 subframe.

32. The method of claim 28, wherein the system information message is broadcast to one or more machine type communication (MTC) devices.

33. An apparatus configured for handling emergency events, the apparatus comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory, the instructions being executable to;

receive an emergency message;

change scheduling information and message data;

update a current access class; and

broadcast a system information message with the scheduling information and the current access class.

34. The apparatus of claim 33, wherein the instructions are further executable to send a paging message to wireless devices indicating the emergency message and a change in scheduling data.

35. The apparatus of claim 33, wherein the scheduling information is broadcast in an SIB1 subframe.

36. The apparatus of claim 33, wherein the current access class is broadcast in an SIB2 subframe.

37. The apparatus of claim 33, wherein the system information message is broadcast to one or more machine type communication (MTC) devices.