RECEIVING CELL BROADCAST (CB) MESSAGES

• US 20130176951A1
• Filed: 07/12/2012
• Published: 07/11/2013
• Est. Priority Date: 07/15/2011
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Dhanda, Mungal Singh, Gupta, Ajit, Walke, Simon, Kanthala, Venkata Raji Reddy, Mutya, Subbarayudu, Robinson, Nigel Phillip, Janga, Bhanu Kiran
• Granted Patent: US 8,787,262 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04W 36/08 Reselecting an access point
• CPC Class Codes: H04W 4/06 Selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS]; Services to user groups; One-way selective calling services
• 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 48/10 using broadcasted information
• CPC Class Codes: H04W 72/30 Resource management for broadcast services
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

A method for receiving cell broadcast messages is described. The method includes communicating with a first cell. The method also includes switching to communicating with a second cell. A cell broadcast channel is read after switching cells. The method further includes switching from a dedicated mode to a packet idle mode. The cell broadcast channel is reread once after switching from a dedicated mode to a packet idle mode. Other aspects, embodiments and features are also claimed and described.

Claims

1. A method for receiving cell broadcast messages, comprising:

communicating with a first cell;

switching to communicating with a second cell;

reading a cell broadcast channel after switching cells;

switching from a dedicated mode to a packet idle mode; and

rereading the cell broadcast channel once after switching from a dedicated mode to a packet idle mode.

2. The method of claim 1, wherein the method is performed by a wireless communication device.

3. The method of claim 2, wherein the wireless communication device uses one or more subscriber identification module cards.

4. The method of claim 1, wherein cell broadcast scheduling message is not supported by the second cell.

5. The method of claim 1, wherein reading a cell broadcast channel comprises searching the cell broadcast channel for a cell broadcast message.

6. An apparatus for receiving cell broadcast messages, comprising:

a processor;

memory in electronic communication with the processor; and

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

communicate with a first cell;

switch to communicating with a second cell;

read a cell broadcast channel after switching cells;

switch from a dedicated mode to a packet idle mode; and

reread the cell broadcast channel once after switching from a dedicated mode to a packet idle mode.

7. The apparatus of claim 6, wherein the apparatus is a wireless communication device.

8. The apparatus of claim 7, wherein the wireless communication device uses one or more subscriber identification module cards.

9. The apparatus of claim 6, wherein cell broadcast scheduling message is not supported by the second cell.

10. The apparatus of claim 6, wherein reading a cell broadcast channel comprises searching the cell broadcast channel for a cell broadcast message.

11. A method for receiving cell broadcast messages, comprising:

receiving a trigger to read a cell broadcast channel;

determining that a network does not support cell broadcast scheduling messages;

reducing a rate at which the cell broadcast channel is read; and

rereading the cell broadcast channel at the reduced rate.

12. The method of claim 11, wherein the method is performed by a wireless communication device.

13. The method of claim 12, wherein reducing the rate at which the cell broadcast channel is read comprises using pseudo scheduling information.

14. The method of claim 13, wherein the pseudo scheduling information gives a cell broadcast channel higher priority than a paging channel.

15. The method of claim 13, wherein the pseudo scheduling information is such that the wireless communication device reads all cell broadcast message slots until a schedule map has expired.

16. The method of claim 11, further comprising:

determining that all the desired messages have been read; and

discontinuing rereading the cell broadcast channel at the reduced rate.

17. An apparatus for receiving cell broadcast messages, comprising:

a processor;

memory in electronic communication with the processor; and

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

receive a trigger to read a cell broadcast channel;

determine that a network does not support cell broadcast scheduling messages;

reduce a rate at which the cell broadcast channel is read; and

reread the cell broadcast channel at the reduced rate.

18. The apparatus of claim 17, wherein the apparatus is a wireless communication device.

19. The apparatus of claim 18, wherein the instructions executable to reduce the rate at which the cell broadcast channel is read comprise instructions executable to use pseudo scheduling information.

20. The apparatus of claim 19, wherein the pseudo scheduling information gives a cell broadcast channel higher priority than a paging channel.

21. The apparatus of claim 19, wherein the pseudo scheduling information is such that the wireless communication device reads all cell broadcast message slots until a schedule map has expired.

22. The apparatus of claim 17, wherein the instructions are further executable to:

determine that all the desired messages have been read; and

discontinue rereading the cell broadcast channel at the reduced rate.

23. A method for receiving cell broadcast messages, comprising:

monitoring a cell broadcast channel;

calculating slots where a desired message is expected in the cell broadcast channel; and

reading the cell broadcast channel only at the calculated slots.

24. The method of claim 23, wherein the method is performed by a wireless communication device.

25. The method of claim 23, wherein the cell broadcast channel is monitored for a continuous scan time to obtain a number of repetitions, a periodicity, and a last slot number.

26. The method of claim 25, wherein the repetitions, the periodicity, and the last slot number are used to calculate slots where a desired message is expected.

27. The method of claim 23, further comprising performing a cell broadcast continuous scan procedure if predictive scheduling has failed for any desired message.

28. The method of claim 23, wherein reading the cell broadcast channel only at the calculated slots is part of a cell broadcast predictive scan procedure.

29. The method of claim 28, further comprising performing a cell broadcast continuous scan procedure if a refresh timer expires during the cell broadcast predictive scan procedure.

30. The method of claim 23, wherein the method is performed in a network that does not support a cell broadcast scheduling mechanism.

31. The method of claim 30, wherein monitoring a cell broadcast channel comprises:

starting a continuous scan timer;

reading all cell broadcast message slots; and

determining whether a message ID and an update number have changed since a previous cell broadcast channel slot.

32. The method of claim 31, wherein at least one of the message ID and update number have changed since the previous cell broadcast message slot, and further comprising incrementing the number of repetitions for the message ID.

33. The method of claim 32, further comprising storing the message ID, a cell ID, the number of repetitions, a last message slot number, and calculated periodicity when the continuous scan timer expires.

34. The method of claim 32, wherein the message ID, the cell ID, the number of repetitions, the last message slot number, and the calculated periodicity are used to calculate slots where a desired message is expected.

35. An apparatus for receiving cell broadcast messages, comprising:

a processor;

memory in electronic communication with the processor; and

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

monitor a cell broadcast channel;

calculate message slots where a desired message is expected in the cell broadcast channel; and

read the cell broadcast channel only at the calculated message slots.

36. The apparatus of claim 35, wherein the apparatus is a wireless communication device.

37. The apparatus of claim 35, wherein the cell broadcast channel is monitored for a continuous scan time to obtain a number of repetitions, a periodicity, and a last slot number.

38. The apparatus of claim 37, wherein the repetitions, the periodicity, and the last slot number are used to calculate slots where a desired message is expected.

39. The apparatus of claim 35, wherein the instructions are further executable to perform a cell broadcast continuous scan procedure if predictive scheduling has failed for any desired message.

40. The apparatus of claim 35, wherein reading the cell broadcast channel only at the calculated slots is part of a cell broadcast predictive scan procedure.

41. The apparatus of claim 40, wherein the instructions are further executable to perform a cell broadcast continuous scan procedure if a refresh timer expires during the cell broadcast predictive scan procedure.

42. The apparatus of claim 35, wherein the apparatus is located in a network that does not support a cell broadcast scheduling mechanism.

43. The apparatus of claim 42, wherein the instructions executable to monitor a cell broadcast channel comprise instructions executable to:

start a continuous scan timer;

read all cell broadcast message slots; and

determine whether a message ID and an update number have changed since a previous cell broadcast channel slot.

44. The apparatus of claim 43, wherein at least one of the message ID and update number have changed since the previous cell broadcast message slot, and further comprising incrementing the number of repetitions for the message ID.

45. The apparatus of claim 44, wherein the instructions are further executable to store the message ID, a cell ID, the number of repetitions, a last message slot number, and calculated periodicity when the continuous scan timer expires.

46. The apparatus of claim 44, wherein the message ID, the cell ID, the number of repetitions, the last message slot number, and the calculated periodicity are used to calculate slots where a desired message is expected.

47. A computer-program product for a receiving cell broadcast messages, the computer-program product comprising a non-transitory computer-readable medium having instructions thereon, the instructions comprising:

code for causing a wireless device to communicate with a first cell;

code for causing the wireless device to switch to communicating with a second cell;

code for causing the wireless device to read a cell broadcast channel after switching cells;

code for causing the wireless device to switch from a dedicated mode to a packet idle mode; and

code for causing the wireless device to reread the cell broadcast channel once after switching from a dedicated mode to a packet idle mode.

48. A computer-program product for a receiving cell broadcast messages, the computer-program product comprising a non-transitory computer-readable medium having instructions thereon, the instructions comprising:

code for causing a wireless device to monitor a cell broadcast channel;

code for causing the wireless device to calculate message slots where a desired message is expected in the cell broadcast channel; and

code for causing the wireless device to read the cell broadcast channel only at the calculated message slots.

49. A computer-program product for a receiving cell broadcast messages, the computer-program product comprising a non-transitory computer-readable medium having instructions thereon, the instructions comprising:

code for causing a wireless device to monitor a cell broadcast channel;

code for causing the wireless device to calculate message slots where a desired message is expected in the cell broadcast channel; and

code for causing the wireless device to read the cell broadcast channel only at the calculated message slots.