Imminent change warning

• US 5,732,347 A
• Filed: 06/06/1995
• Issued: 03/24/1998
• Est. Priority Date: 01/26/1994
• Status: Expired due to Term

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: OKI Telecom, Inc. (OKI Electric Industry Company Limited)
• Inventors: Bartle, Alden S., Erickson, George D.
• Primary Examiner(s): Coles, Sr., Edward L.
• Assistant Examiner(s): Williams, Kimberly A.
• Application Number:
  US08/466,067
• Time in Patent Office: 1,022 Days
• Field of Search: 379/58, 379/59, 379/60, 379/63, 455/33.1, 455/33.2, 455/54.1, 455/127, 455/421, 455/422, 455/436, 455/438, 455/524, 371/2.1, 371/5.1
• US Class Current: 455/421
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 36/14 Reselecting a network or an air interface
• CPC Class Codes: H04W 36/30 by measured or perceived connection quality data
• CPC Class Codes: H04W 76/30 Connection release
• CPC Class Codes: H04W 84/042 Public Land Mobile systems, e.g. cellular systems
• CPC Class Codes: H04W 88/02 Terminal devices

Abstract

A cellular telephone, in its most preferred embodiment, performs a method for notifying a digital cellular telephone user of an imminent communication disconnection. The preferred method includes, at least, generating at least one condition indication representative of at least one communication condition, analyzing the condition indication, determining whether a communication disconnection is imminent, enhancing quality of received communication signals when possible, and notifying the user of an imminent communication disconnection. Exemplary condition indications include, at least, continuous count and rate indications of frame checksum errors, insufficient quality frames, symbol errors, and chip errors, output power level indication, received signal strength indication, soft handoff status indication, other pilot signal indication, and current pilot signal strength indication. One exemplary analysis technique of determining when a communication disconnection is imminent includes evaluating whether any of a set of condition indications violates a predefined threshold indication, while other exemplary analysis techniques include evaluating whether fixed or historically adaptive combinations of condition indications violate run predefined thresholds, and evaluating combinations of condition indications weighted according to the degree of threshold violation. The process further uses a memory flag in a delayed redundant comparison before enabling a warning, examples of which include visual, sensory, and audible notification methods, including adding generated noise to the received audio signal. Alternate methods of the invention include notifying a user of an imminent inter-system handoff or an imminent change in communication mode.

Claims

1. A method of notifying a user of a digital cellular telephone during digital cellular communication of an imminent digital communication disconnection, said method comprising the steps of:

generating a condition indication representative of a digital communication condition, including generating a transmitter output power level indication, and

analyzing the condition indication to determine whether a digital communication disconnection is imminent, including determining whether the transmitter output power level indication is less than a predefined low power threshold level; and

notifying the user that a digital communication disconnection is imminent responsive to determining a digital communication disconnection is imminent.

2. A method of notifying a user of a digital cellular telephone during digital cellular communication of an imminent digital communication disconnection, said method comprising the steps of:

generating a condition indication representative of a digital communication condition;

analyzing the condition indication to determine whether a digital communication disconnection is imminent;

notifying the user that a digital communication disconnection is imminent responsive to determining a digital communication disconnection is imminent; and

continually repeating the generating and analyzing steps during a telephone call,

wherein the generating a condition indication step includes, at least, the steps of

evaluating current frame validity, including, at least, the steps of

calculating a current frame checksum, and

comparing the calculated frame checksum to a predefined frame checksum,

generating a frame checksum error responsive to the calculated frame checksum differing from the predefined frame checksum, and

generating a count of continuous frame checksum errors indication.

3. The method of claim 2, wherein the generating a condition indication step further includes, at least, the step of

generating a rate of frame checksum errors indication.

4. A method of notifying a user of a digital cellular telephone during digital cellular communication of an imminent digital communication disconnection, said method comprising the steps of:

generating a condition indication representative of a digital communication condition;

analyzing the condition indication to determine whether a digital communication disconnection is imminent;

notifying the user that a digital communication disconnection is imminent responsive to determining a digital communication disconnection is imminent;

continually repeating the generating and analyzing steps during a telephone call,

wherein the generating a condition indication step includes, at least, the steps of

evaluating current frame quality to determine whether the current frame is of insufficient quality,

generating a current insufficient quality frame error responsive to determining the current frame is of insufficient quality, and

generating a count of continuous insufficient quality frame errors indication.

5. The method of claim 4, wherein the generating a condition indication step further includes, at least, the step of

generating a rate of insufficient quality frame errors indication.

6. A method of notifying a user of a digital cellular telephone during digital cellular communication of an imminent digital communication disconnection, said method comprising the steps of:

generating a condition indication representative of a digital communication condition;

analyzing the condition indication to determine whether a digital communication disconnection is imminent;

notifying the user that a digital communication disconnection is imminent responsive to determining a digital communication disconnection is imminent;

continually repeating the generating and analyzing steps during a telephone call,

wherein the generating a condition indication step includes, at least, the steps of

evaluating current symbol quality to determine whether the current symbol is of insufficient quality,

generating a current insufficient quality symbol error responsive to determining the current symbol is of insufficient quality, and

generating a count of continuous insufficient quality symbol errors indication.

7. The method of claim 6, wherein the generating a condition indication step further includes, at least, the step of

generating a rate of insufficient quality symbol errors indication.

8. A method of notifying a user of a digital cellular telephone during digital cellular communication of an imminent digital communication disconnection, said method comprising the steps of:

generating a condition indication representative of a digital communication condition;

analyzing the condition indication to determine whether a digital communication disconnection is imminent;

notifying the user that a digital communication disconnection is imminent responsive to determining a digital communication disconnection is imminent;

continually repeating the generating and analyzing steps during a telephone call,

wherein the generating a condition indication step includes, at least, the steps of

evaluating current chip quality to determine whether the current chip is of insufficient quality,

generating a current insufficient quality chip error responsive to determining the current chip is of insufficient quality, and

generating a count of continuous insufficient quality chip errors indication.

9. The method of claim 8, wherein the generating a condition indication step further includes, at least, the step of

generating a rate of insufficient quality chip errors indication.

10. A method of notifying a user of a digital cellular telephone during digital cellular communication of an imminent digital communication disconnection, said method comprising the steps of:

generating a condition indication representative of a digital communication condition, including generating a transmitter output power level indication;

analyzing the condition indication to determine whether a digital communication disconnection is imminent, including determining whether the transmitter output power level indication is greater than a predefined high power threshold level; and

notifying the user that a digital communication disconnection is imminent responsive to determining a digital communication disconnection is imminent.

11. A method of notifying a user of a digital cellular telephone during digital cellular communication of an imminent digital communication disconnection, said method comprising the steps of:

generating a condition indication representative of a digital communication condition;

analyzing the condition indication to determine whether a digital communication disconnection is imminent;

notifying the user that a digital communication disconnection is imminent responsive to determining a digital communication disconnection is imminent; and

enhancing received communication signal quality responsive to determining a digital communication disconnection is imminent.

12. The method of claim 11, wherein the enhancing step includes allocating power to additional digital cellular telephone receiver components.

13. The method of claim 11, wherein the generating a condition indication step includes generating a condition indication representative of a digital communication condition in a code division multiple access digital cellular telephone, and wherein the enhancing step includes operating additional demodulator fingers to enhance received communication quality.

14. The method of claim 11, wherein the generating a condition indication step includes generating a condition indication representative of a digital communication condition in a code division multiple access digital cellular telephone, and wherein the enhancing step includes operating additional echo cancelers to cancel additional intersymbol interference.

15. The method of claim 11, wherein the generating a condition indication step includes generating a condition indication representative of a digital communication condition in a code division multiple access digital cellular telephone, and wherein the enhancing step includes substituting previous frames for current frames.

16. A cellular telephone apparatus comprising:

a user interface; and

a control system, coupled to said user interface, including

means for controlling said user interface,

means for storing programming information for directing operation of said apparatus,

means for generating, at said apparatus, a first condition indication representative of a first received signal communication condition,

means for generating, at said apparatus, a second condition indication representative of a second received signal communication condition, wherein the first communication condition and the second communication condition are distinct and different types of received signal communication conditions,

means for analyzing both the first condition indication and the second condition indication to determine, at said apparatus, whether a communication mode change is imminent, and

means for notifying a user of said apparatus that the communication mode change is imminent responsive to determining the communication mode change is imminent.

17. The apparatus of claim 16, wherein said user interface includes

a transceiver coupled to said control system,

an antenna coupled to said transceiver,

a microphone coupled to said control system,

a speaker coupled to said control system,

a keypad coupled to said control system, and

a visual display coupled to said control system.

18. The apparatus of claim 17, wherein said control system further includes means for disabling said noticing means through user-configurable settings accessed through said keypad.

19. The apparatus of claim 16, wherein the communication mode change includes changing from a digital operation mode to an analog operation mode.

20. The apparatus of claim 16, wherein the communication mode change includes changing from an analog operation mode to a digital operation mode.

21. The apparatus of claim 16, wherein the communication mode change includes an intersystem handoff.

22. The apparatus of claim 16, wherein the communication mode change includes an imminent disconnection.

23. The apparatus of claim 16, wherein said analyzing means includes means for evaluating the first condition indication and the second condition indication as weighted factors in determining whether the communication mode change is imminent.

24. The apparatus of claim 16, wherein said analyzing means includes

means for comparing the first condition indication to a predefined first condition threshold,

means for comparing the second condition indication to a predefined second condition threshold, and

means for determining that the communication mode change is imminent if either predefined condition threshold is violated.

25. The apparatus of claim 16, wherein said control system further includes means for adaptively enhancing received communication signal quality, with no required action on an operating member, responsive to determining the communication mode change is imminent.

26. In a communication system in which a user of a cellular telephone is notified of an imminent communication mode change, said system comprising

means for generating a first condition indication, at said cellular telephone, representative of a first communication condition during a first period;

means for comparing, at said cellular telephone, the first condition indication to a first predefined condition threshold;

means for initiating a delayed redundant comparison responsive to results of said first condition comparing means;

means for generating a second condition indication, at said cellular telephone, representative of a second communication condition during a second period;

means for comparing, at said cellular telephone, the second condition indication to a second predefined condition threshold;

means for analyzing, at said cellular telephone, results of said initiating means and results of said second condition comparing means to determine whether a communication mode change is imminent; and

means for notifying said user that the communication mode change is imminent responsive to determining that the communication mode change is imminent.

27. The system of claim 26, wherein said initiating means includes means for setting a flag memory element responsive to said first condition comparing means.

28. The system of claim 26, further comprising means for re-initiating the delayed redundant comparison responsive to said analyzing means determining the communication mode change is not imminent.

29. The system of claim 26,

wherein the communication mode change defines an inter-system handoff,

wherein the first communication condition defines a cellular handoff status,

wherein the second communication condition defines a current pilot signal strength, and

wherein said analyzing means includes determining the inter-system handoff is imminent when both the current pilot signal strength is below a predefined current pilot signal strength threshold and said cellular telephone is experiencing a soft handoff.

30. The system of claim 26, wherein the first communication condition is identical to the second communication condition.

31. The system of claim 26,

wherein the first predefined condition threshold defines a high power threshold level,

wherein the first condition indication defines a transmitter output power level indication which indicates an amount of power output by a transceiver of said cellular telephone,

wherein the transmitter output power level indication is greater than the high power threshold level, and

wherein said first condition comparing means includes means for reducing the amount of power output by said transceiver.

32. The system of claim 26, wherein said analyzing means further includes means for delaying for a predefined amount of time before determining the communication mode change is imminent.

33. The system of claim 26, wherein said notifying means includes means for generating an audible sound.

34. The system of claim 26, wherein said notifying means includes means for generating a visual warning indication.

35. The system of claim 26, wherein said notifying means includes means for activating a vibration device.

36. The system of claim 26, further comprising means for changing the communication mode responsive to determining the communication mode change is imminent.

37. A digital cellular telephone apparatus for communicating in a digital communication mode, said apparatus comprising:

means for generating a condition indication representative of a digital communication condition;

means for analyzing the condition indication to determine whether a digital communication disconnection is imminent;

means for notifying a user of said digital cellular telephone that the digital communication disconnection is imminent responsive to determining the digital communication disconnection is imminent; and

means for adaptively enhancing received communication signal quality responsive to determining the digital communication disconnection is imminent.

38. The apparatus of claim 37, wherein said adaptively enhancing means includes means for setting decoder parameters to use a full length constraint length to reduce symbol errors.