Conservation of battery power in mobile devices having communication capabilities

• US 20050261037A1
• Filed: 05/18/2004
• Published: 11/24/2005
• Est. Priority Date: 05/18/2004
• Status: Abandoned Application

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Narayanaswami, Chandrasekhar, Raghunath, Mandayam T.
• Application Number:
  US10/848,301
• Publication Number:
  US 20050261037A1
• Time in Patent Office: Days
• US Class Current: 455/574
• CPC Class Codes: H04W 52/0229 where the received signal is a wanted signal
• 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: Y02D 30/70 in wireless communication networks

Abstract

A method, apparatus and computer program product that in a mobile data communications system having at least one base station, at least one beacon and at least one mobile device, enables the mobile devices to conserve power. A wireless communication subsystem in each mobile device communicates with the base station. A beacon either signals the presence of a main base station or the need for the mobile device to attempt to associate or communicate with the base station. A beacon detection circuit in a mobile device activates the wireless communication subsystem in the mobile device when the beacon is received by the beacon detection circuit, which may be a passive circuit using no power, or a very low power receiver.

Claims

1. A mobile data communications system having at least one base station and at least one mobile device, comprising:

a wireless communication subsystem in each mobile device for communicating with said at least one base station,

a beacon for signaling at least one of a presence of a base station and a need for a mobile device to associate or communicate with a base station; and

a beacon detection circuit in a mobile device for performing at least one of activating said wireless communication subsystem in said mobile device, and alerting a user of said mobile device to conduct communication with a base station, when said beacon is received by said beacon detection circuit.

2. The system as recited in claim 1, wherein said beacon has a range less than that of said wireless communication subsystem, and said wireless communication subsystem is activated when said mobile device is in proximity to a location of a beacon.

3. The system of claim 2, wherein said beacon transmits data indicative of a class of mobile devices to which messages are to be sent.

4. The system of claim 1, wherein said beacon range is larger than that of said wireless communication subsystem.

5. The system of claim 4, wherein said beacon provides an indication of the particular mobile devices to which a message is to be sent.

6. The system as recited in claim 1, wherein said beacon comprises a signal transmitted by one of a broadcast station, a satellite radio channel, and a cell phone base station, and said beacon detection circuit is configured for receiving said signal.

7. The system as recited in claim 1, wherein said beacon is a radio frequency transmitter, and said beacon detection circuit comprises a passive detection circuit for converting energy received from said radio frequency transmitter to a logic signal.

8. The system as recited in claim 7, wherein said passive detection circuit comprises an antenna, a passive energy converter, and a capacitor for storing energy from said passive energy converter.

9. The system as recited in claim 1, wherein said beacon comprises a transmitter for transmitting a radio frequency transmission at multiple frequencies and said beacon detection circuit comprises a detection circuit for converting energy received from said radio frequency transmission at multiple frequencies into a logic signal for each frequency received.

10. The system as recited in claim 9, wherein said beacon detection circuit comprises logic circuitry for detecting an address of a device to which the beacon is sending an alert.

11. The system as recited in claim 9, wherein said beacon detection circuit comprises logic circuitry for combining said logic signals to detect addresses of a class of devices to which the beacon is sending an alert.

12. The system as recited in claim 9, wherein said radio frequency transmitter transmits data including at least one of a device identifier, times at and durations for which said wireless communication subsystem on a device must be turned on, base station identifier, base station location, additional authentication information, and data to be used in subsequent wireless communication with the base station.

13. The system as recited in claim 9, wherein data to be used in subsequent wireless communication said data to be used in subsequent communication includes at least one of security keys or passwords.

14. The system as recited in claim 1, wherein said beacon is an ultrasound transmitter, and said beacon detection circuit comprises a passive ultrasound detection circuit for receiving signals from said ultrasound transmitter.

15. The system as recited in claim 1, wherein said beacon detection circuit comprises circuitry to compare an identifier in a signal received from said beacon with device identification of the mobile device.

16. The system as recited in claim 1, wherein said beacon is a radio frequency transmitter, and said beacon detection circuit comprises a low power receiver for receiving signals from said radio frequency transmitter.

17. The system as recited in claim 1, wherein said at least one mobile device comprises a device selected from the group consisting of a wrist watch, a PDA, and a cell phone.

18. A mobile device for use in a mobile data communications system having at least one base station, and a beacon, said mobile device comprising:

a wireless communication subsystem for communicating with said base station, and

a beacon detection circuit in said mobile device for performing at least one of activating said wireless communication subsystem in said mobile device and alerting a user of said mobile device to conduct communication with a base station, when said beacon is received by said beacon detection circuit.

19. The device as recited in claim 18, wherein said beacon is a radio frequency transmitter, and said beacon detection circuit comprises a passive detection circuit for converting energy received from said radio frequency transmitter to a logic signal.

20. The device as recited in claim 19, wherein said passive detection circuit comprises an antenna, a passive energy converter, and a capacitor for storing energy from said passive energy converter.

21. The device as recited in claim 18, wherein said beacon is a radio frequency transmitter, and said beacon detection circuit comprises a low power receiver for receiving signals from said radio frequency transmitter.

22. The device as recited in claim 18, configured as a device selected from the group consisting of a wrist watch, a PDA, and a cell phone.

23. The device as recited in claim 18, wherein said beacon comprises a transmitter for transmitting a radio frequency transmission at multiple frequencies and said beacon detection circuit comprises a detection circuit for converting energy received from said radio frequency transmission at multiple frequencies into a logic signal for each frequency received.

24. The device as recited in claim 23, wherein said beacon detection circuit comprises logic circuitry for detecting an address of a device to which the beacon is sending an alert.

25. The device as recited in claim 23, wherein said beacon detection circuit comprises logic circuitry for combining said logic signals to detect addresses of a class of devices to which the beacon is sending an alert.

26. The device as recited in claim 23, wherein said radio frequency transmitter transmits data including at least one of a device identifier, times at and durations for which said wireless communication subsystem on a device must be turned on, base station identifier, base station location, additional authentication information, and data to be used in subsequent wireless communication with the base station.

27. The device as recited in claim 23, wherein data to be used in subsequent wireless communication said data to be used in subsequent communication includes at least one of security keys or passwords.

28. A method for operating a mobile data communications system having at least one base station and at least one mobile device, comprising:

monitoring for at least one of proximity to a base station of said at least one mobile device and an alert from a beacon; and

performing at least one of activating a wireless communication subsystem in said at least one mobile device for communicating with said base station when in proximity to a base station, or in response to said alert, and providing an alert to a user of said mobile device that there is a message to be received.

29. A method as recited in claim 28, wherein said monitoring comprises:

detecting a beacon signaling the presence of a base station; and

activating said wireless communication subsystem in said mobile device when said beacon is detected by said device.

30. A method as recited in claim 28, further comprising:

placing on said beacon a signal containing an address of a mobile device; and

activating said wireless communication subsystem in a mobile device when said beacon is detected by said device and said beacon contains an address of said mobile device.

31. A method as recited in claim 28, further comprising:

placing on said beacon a signal containing an address indicative of a class of mobile devices; and

activating said wireless communication subsystem in a mobile device when said beacon is detected by said mobile device and said beacon contains said address indicative of a class of mobile devices to which said device belongs.

32. A method as recited in claim 28, further comprising providing at least one of visual indication, a tactile indication and an audio indication, to a user of said device that an alert from a beacon has been detected.

33. A method as recited in claim 28, further comprising ascertaining a state of charge of a battery powering said device when said beacon has been detected.

34. A method as recited in claim 28, wherein when said state of charge of said battery is low, activating said wireless communication subsystem upon command of a user of said device.

35. A method as recited in claim 34, wherein if a state of charge of said battery changes so that it is not low, the method further comprises again monitoring for proximity of a base station to said at least one mobile device.

36. A method as recited in claim 28, further comprising establishing a polling schedule for the transfer of data between said base station and said at least one mobile device.

37. A method as recited in claim 28, wherein if communication between said base station and said at least one mobile device is lost, the method further comprises monitoring for proximity of a base station to said at least one mobile device.

38. A method as recited in claim 28, further comprising providing an indication to a user of said mobile device that communication between a base station and said mobile device is not established.

39. A method as recited in claim 28, wherein when the mobile device is not in proximity to a base station, said wireless communication subsystem is turned off.

40. A method as recited in claim 28, wherein said wireless communication subsystem is turned on only when a mobile device in which it is contained is in proximity to a base station.

41. An article of manufacture comprising a computer usable medium having computer readable program code means embodied therein for causing a mobile data communications system having at least one base station and at least one mobile device, to execute steps comprising:

monitoring for at least one of proximity of a base station to said at least one mobile device and an alert from a beacon; and

performing at least one of activating a wireless communication subsystem in said at least one mobile device for communicating with said base station when in proximity to a base station, or in response to said alert, and providing an alert to a user of said mobile device that there is a message to be received.

42. An article as recited in claim 41, further comprising computer code for performing said monitoring by:

detecting a beacon associated with a base station; and

activating said wireless communication subsystem in said mobile device when said beacon is detected by said device.

43. An article as recited in claim 41, further comprising computer code for causing said device to provide an indication to a user of said device that a beacon has been detected.

44. An article as recited in claim 41, further comprising computer code for ascertaining a state of charge of a battery powering said device when said beacon has been detected.

45. An article as recited in claim 44, further comprising computer code for activating said wireless communication subsystem upon command of a user of said device when said state of charge of said battery is low.

46. An article as recited in claim 45, further comprising computer code for again monitoring for proximity of a base station to said at least one mobile device, if a state of charge of said battery changes so that it is not low.

47. An article as recited in claim 41, further comprising computer code for establishing a polling schedule for the transfer of data between said base station and said at least one mobile device.

48. An article as recited in claim 47, further comprising computer code for monitoring for proximity of a base station to said at least one mobile device if communication between said base station and said at least one mobile device is lost.

49. An article as recited in claim 41, further comprising computer code for causing said mobile device to provide an indication to a user of said mobile device that communication between a base station and said mobile device is not established.

50. An article as recited in claim 41, further comprising computer code for turning off said wireless communication subsystem when the mobile device is not in proximity to a base station.

51. An article as recited in claim 41, further comprising computer code for turning on said wireless communication subsystem only when a mobile device in which it is contained is in proximity to a base station.