Battery saver for a tone coded signalling system

• US 4,181,893 A
• Filed: 12/30/1976
• Issued: 01/01/1980
• Est. Priority Date: 06/26/1975
• Status: Expired due to Term

• Current Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Ehmke, Edward L.
• Primary Examiner(s): Richardson, Robert L.
• Assistant Examiner(s): Chin, Tommy P.
• Application Number:
  US05/755,696
• Time in Patent Office: 1,097 Days
• Field of Search: 325/492, 325/151, 325/185, 325/186, 325/, 325/321, 325/325, 325/392, 325/55, 325/64, 325/466, 343/228, 340/311, 340/171 P, 340/171 F, 328/258
• US Class Current: 340/7.34
• CPC Class Codes: G08B 3/1066 with other provisions not elsewhere provided for, e.g. turn-off protection
• CPC Class Codes: H04W 52/0229 where the received signal is a wanted signal
• CPC Class Codes: H04W 88/027 using frequency address codes
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A battery saver circuit for a tone coded personalized radio pager device or the like is described which includes a switchable frequency tone filter to detect a predetermined sequence of tones. One of several alert signals is generated when the correct sequential tone code of the device has been detected.

Power is periodically applied to a receiver by a power supply circuit and a control circuit. The first code tone is sampled three times to protect against false identification of this tone. After this first (preamble) tone has been validated, power is supplied for an additional duration of time and the filter is set to detect the next code tone. Once the second code tone has been detected, if the next code tone is not detected within a predetermined time window, the control circuit resets the switchable filter to again search for the second tone of the code. By resetting the filter to detect the second tone, it is possible to condense the broadcast time required for a string of coded messages.

Claims

1. An improved battery saver circuit for use with personalized radio apparatus operable on receipt of a predetermined sequential tone code having at least first, second, and third tones, said battery saver circuit comprising:

receiver means for receiving tone modulated input signals and providing corresponding output tone signals in response thereto at a reference terminal;

power supply means coupled to said receiver means for selectively supplying operating power thereto;

detector means coupled to said receiver reference terminal for indicating a detection in response to said output tone signals having a predetermined frequency; and

control means coupled to said power supply means and said detecting means for selectively controlling the same;

said control means including,

first circuit means for enabling said power supply means to periodically supply operating power to said receiver for a first predetermined time duration and for effecting the selection of a first frequency that said detector means will respond to,

second circuit means for enabling said power supply means to supply operating power for a second predetermined time duration in response to said first frequency being detected during said first time duration,

third circuit means for enabling said power supply means to supply operating power for a third predetermined time duration and effecting the selection of a second frequency in response to said first frequency being detected during said second time duration,

fourth circuit means for enabling said power supply means to supply operating power for a fourth predetermined time duration and effecting the selection of a third frequency in response to said second frequency being detected, and

fifth circuit means for effecting the selection of said second frequency in response to said third frequency not being detected within a predetermined time window after said second frequency has been detected.

2. An improved battery saver circuit for use with personalized radio apparatus operable on receipt of a predetermined sequential tone code having at least first and second tones, said battery saver circuit comprising:

receiver means for receiving tone modulated input signals and providing corresponding output tone signals in response thereto at a reference terminal;

power supply means coupled to said receiver means for selectively supplying operating power thereto;

detector means coupled to said receiver reference terminal for indicating a detection in response to said output tone signals having a predetermined frequency; and

control means coupled to said power supply means and said detecting means for selectively controlling the same;

said control means including,

first circuit means for enabling said power supply means to periodically supply operating power to said receiver for a first predetermined time duration and for effecting the selection of a first frequency that said detector means will respond to,

second circuit means for enabling said power supply means to supply operating power for a second predetermined time duration in response to said first frequency being detected during said first time duration, and

third circuit means for enabling said power supply means to supply operating power for a third predetermined time duration and effecting the selection of a second frequency in response to said first frequency being detected during said second time duration.

3. An improved battery saver circuit according to claim 2 wherein said receiver means is a radio receiver and said power supply means includes a battery.

4. An improved battery saver circuit according to claim 2 wherein said control means includes timing means for generating timing pulses.

5. An improved battery saver circuit according to claim 4 wherein said timing means includes a pulse generating clock and a down counter.

6. An improved battery saver circuit according to claim 5 wherein said control means includes a detect counter for counting the number of detections.

7. An improved battery saver circuit according to claim 6 wherein said control means includes alert means for producing an alert signal after all of the tones of the predetermined code are properly sequentially identified.

8. An improved battery saver circuit according to claim 7 wherein said control means includes circuit means for causing the power supplied to said receiver means to be cut off in response to said alert signal being generated.

9. An improved battery saver circuit for use with personalized radio apparatus operable on receipt of a predetermined sequential tone code having at least first, second, and third tones, said battery saver circuit comprising:

receiver means for receiving tone modulated input signals and providing corresponding output tone signals in response thereto at a reference terminal;

power supply means coupled to said receiver means for selectively supplying operating power thereto;

detector means coupled to said receiver reference terminal for indicating a detection in response to said output tones having a predetermined frequency; and

control means coupled to said power supply means and said detecting means for selectively controlling the same;

said control means including,

first circuit means for enabling said power supply means to periodically supply operating power to said receiver for a first predetermined time duration and for effecting the selection of a first frequency that said detector means will respond to,

second circuit means for enabling said power means to supply operating power for a second predetermined time duration and effecting the selection of a second frequency in response to said first frequency being detected,

third circuit means for enabling said power means to supply operating power for a third predetermined time duration and effecting the selection of a third frequency in response to said second frequency being detected, and

fourth circuit means for effecting the selection of said second frequency in response to said third frequency not being detected within a predetermined time window after said second frequency has been detected.

10. An improved battery saver circuit for use with personalized radio apparatus operable on receipt of a predetermined sequential tone code having at least first and second tones, said battery saver circuit comprising:

receiver means for receiving tone modulated input signals and providing corresponding output tone signals in response thereto at a reference terminal;

power supply means coupled to said receiver means for selectively supplying operating power thereto;

detector means coupled to said receiver reference terminal for indicating a detection in response to said output tone signals having a predetermined frequency; and

control means coupled to said power supply means and said detecting means for selectively controlling the same;

said control means including,

first circuit means for enabling said power supply means to periodically supply operating power to said receiver for a first predetermined time duration and for effecting the selection of a first frequency that said detector means will respond to,

second circuit means for enabling said power supply means to supply operating power for a second predetermined time duration and effecting the selection of a second frequency in response to said first frequency being detected and said output tone signals having said first frequency for at least a first detect time duration, and

third circuit means for generating an alert signal in response to said second frequency being detected and said output tone signals having said second frequency for at least a second detect time duration,

said first detect time duration being greater than said second detect time duration.

11. A multiple alert receiver operable in response to receiving a predetermined tone code, said receiver comprising:

receiver means for receiving transmitted signals;

detector means coupled to said receiver means for indicating a detection in response to a predetermined code being received by said receiver means; and

alert means coupled to said receiver means and said detector means for selecting and generating at least one of several alert signals in response to said detector means indicating a code detection and an additional signal being received by said receiver means, the additional received signal determining which of said several alert signals will be generated;

wherein the predetermined code includes at least one tone and said detector means includes circuitry for searching for said tone within a first time window duration and wherein said alert means includes circuitry for searching for said additional signal within a second time window duration, occurring after the code detection, which is greater than said first time window duration, whereby the receiver will be more likely to select a correct alert signal after said predetermined code has been identified.

12. A multiple alert receiver according to claim 11 wherein said additional signal includes at least one tone.

13. An improved battery saver circuit for use with personalized radio apparatus operable on receipt of a predetermined sequential signal code having at least first and second predetermined code signals, said battery saver circuit comprising:

receiver means for receiving modulated input signals and providing corresponding output signals in response thereto at a reference terminal;

power supply means coupled to said receiver means for selectively supplying operating power thereto;

detector means coupled to said receiver reference terminal for indicating a detection in response to said output signals corresponding to predetermined code signals; and

control means coupled to said power supply means and said detecting means for selectively controlling the same;

said control means including,

first circuit means for enabling said power supply means to periodically supply operating power to said receiver means for a first predetermined time duration and for effecting the selection of a first predetermined code signal that said detector means will respond to,

second circuit means for enabling said power supply means to supply operating power to said receiver means for a second time duration subsequent to and in response to said first predetermined code signal being detected during said first time duration, and

third circuit means for effecting the selection of a second predetermined code signal subsequent to and in response to at least said first predetermined code signal being detected during said second time duration,

whereby looking for said second predetermined code signal is accomplished only after multiply detecting said first predetermined code signal.

14. A battery saver circuit as claimed in claim 13 wherein said third circuit means includes circuitry for enabling said power supply means to supply operating power to said receiver means for a third time duration subsequent to and in response to at least said first code signal being detected during said second time duration, whereby said third time duration is at least long enough to permit detection of said second predetermined code signal and whereby providing power to said receiver means for detecting said second code signal is accomplished only after multiply detecting said first code signal.

15. A battery saver circuit as claimed in claim 14 wherein said control means includes fourth circuit means for supplying power to said receiver means for a fourth time duration subsequent to and in response to said second code signal being detected during said third time duration, whereby said fourth time duration is long enough to permit detection of a code signal following said second code signal.

16. A battery saver circuit as claimed in claim 15 wherein said predetermined code signals are tone signals having different frequencies and wherein said detector means comprises tone detector means for determining frequency correspondence.

17. An improved battery saver circuit for use with personalized radio apparatus operable on receipt of a predetermined sequential signal code having at least first, second, and third predetermined code signals, said battery saver circuit comprising:

receiver means for receiving modulated input signals and providing corresponding output signals in response thereto at a reference terminal;

power supply means coupled to said receiver means for selectively supplying operating power thereto;

detector means coupled to said receiver reference terminal for indicating a detection in response to said output signals corresponding to predetermined code signals; and

control means coupled to said power supply means and said detecting means for selectively controlling the same;

said control means including,

first circuit means for enabling said power supply means to periodically supply operating power to said receiver for a first predetermined time duration and for effecting the selection of a first predetermined code signal that said detector means will respond to,

second circuit means for enabling said power means to supply operating power for a second predetermined time duration and effecting the selection of a second predetermined code signal in response to said first predetermined code signal being detected,

third circuit means for enabling said power means to supply operating power for a third predetermined time duration and effecting the selection of a third predetermined code signal in response to said second predetermined code signal being detected, and

fourth circuit means for effecting the selection of said second predetermined code signal in response to said third predetermined code signal not being detected within a predetermined time window after said second predetermined code signal has been detected.

18. An improved battery saver circuit for use with personalized radio apparatus operable on receipt of a predetermined sequential signal code having at least first and second predetermined code signals, said battery saver circuit comprising:

receiver means for receiving modulated input signals and providing corresponding output signals in response thereto at a reference terminal;

power supply means coupled to said receiver means for selectively supplying operating power thereto;

detector means coupled to said receiver reference terminal for indicating a detection in response to said output signals corresponding to predetermined code signals; and

control means coupled to said power supply means and said detecting means for selectively controlling the same;

said control means including,

first circuit means for enabling said power supply means to periodically supply operating power to said receiver means for a first predetermined time duration and for effecting the selection of a first predetermined code signal that said detector means will respond to,

second circuit means for enabling said power supply means to supply operating power to said receiver means for a second time duration and effecting the selection of a second predetermined code signal subsequent and in response to said first predetermined code signal being detected and said output signals corresponding to said first predetermined code signal for at least a first detect time duration, and

third circuit means for generating an alert signal in response to at least said second predetermined code signal being detected and said output signals corresponding to said second predetermined code signal for at least a second detect time duration,

said first detect time duration being greater than said second detect time duration whereby applying power to said receiver means for looking for said second predetermined code signal occurs only after the detection of a first code signal substantially longer than said second code signal and whereby said second time duration is long enough to permit detection of said second code signal.

19. A battery saver circuit as claimed in claim 18 wherein said predetermined code signals are tone signals having different frequencies and wherein said detector means comprises a tone detector means for determining frequency correspondence.

20. A multiple alert receiver operable in response to receiving a predetermined signal code, said receiver comprising:

receiver means for receiving transmitted signals;

detector means coupled to said receiver means for indicating a detection in response to a predetermined signal code being received by said receiver means; and

alert means coupled to said receiver means and said detector means for selecting and generating at least one of several alert signals in response to said detector means indicating a code detection and an additional signal being received by said receiver means, the additional received signal determining which of said several alert signals will be generated;

wherein the predetermined code includes at least a first predetermined signal and said detector means includes circuitry for searching for said first predetermined signal within a first time window duration and wherein said alert means includes circuitry for searching for said additional signal within a second time window duration, occuring after the code detection which is greater than said first time window duration, whereby the receiver will be more likely to select a correct alert signal after said predetermined code has been identified.

21. A circuit for use with personalized radio apparatus operable on receipt of a predetermined sequential signal code having at least first and second predetermined code signals, said circuit comprising:

receiving means for receiving modulated input signals and providing corresponding output signals in response thereto at a reference terminal;

power supply means coupled to said receiver means for selectively supplying operating power thereto;

detector means coupled to said receiver reference terminal for indicating a detection in response to said output signals corresponding to predetermined code signals; and

control means coupled to said detecting means for selectively controlling the same;

said control means including,

first circuit means for effecting the selection of a first predetermined code signal that said detector means will respond to,

second circuit means for effecting the selection of a second predetermined code signal in response to said first predetermined code signal being detected and said output signals corresponding to said first predetermined code signal for at least a first detect time duration, and

third circuit means for generating an alert signal in response to said predetermined sequential signal code being detected and in response to said second predetermined code signal being detected and said output signals corresponding to said second predetermined code signal for at least a second detect time duration,

said first detect time duration being greater than said second detect time duration,

wherein said predetermined code signals are tone signals having different individual frequencies and wherein said second circuit means includes circuitry for selecting said second predetermined code signal after at least two detections of said first predetermined code signal by said detector means and

wherein said control means is coupled to said power supply means for selectively controlling the same and wherein said first circuit means enables said power supply means to periodically supply operating power to said receiver means for a first predetermined time duration, and wherein said second circuit means enables said power supply means to supply operating power to said receiver means for a second time duration subsequent to and in response to said first predetermined code signal being initially detected.

22. A circuit according to claim 21 wherein said second circuit means includes circuitry for enabling said power supply means to supply operating power to said receiver means for a third time duration subsequent to and in response to said first predetermined code signal being detected during said second time duration, whereby said third duration is at least long enough to detect said second code signal.

23. A circuit for use with personalized radio apparatus operable on receipt of a predetermined sequential signal code having at least first, second and third predetermined code signals, said circuit comprising:

receiver means for receiving modulated input signals and providing corresponding output signals in response thereto at a reference terminal;

power supply means coupled to said receiver means for selectively supplying operating power thereto;

detector means coupled to said receiver reference terminal for indicating a detection in response to said output signals corresponding to predetermined code signals; and

control means coupled to said detecting means for selectively controlling the same;

said control means including,

first circuit means for effecting the selection of a first predetermined code signal that said detector means will respond to,

second circuit means for effecting the selection of a second predetermined code signal in response to said first predetermined code signal being detected,

third circuit means for effecting the selection of a third predetermined code signal in response to said second predetermined code signal being detected, and

fourth circuit means for effecting the selection of said second predetermined code signal in response to said third predetermined code signal not being detected within a predetermined time window after said second predetermined code signal has been detected.

24. A circuit according to claim 23 wherein said control means is coupled to said power supply means for selectively controlling the same and wherein said first circuit means enables said power supply means to periodically supply operating power to said receiver means for a first predetermined time duration, and wherein said second circuit means enables said power supply means to supply operating power to said receiver means for a second predetermined time in response to said first predetermined code signal being detected.

25. A circuit according to claim 24 wherein said predetermined code signals are tone signals having different individual frequencies.

26. A battery saver circuit for use with personalized radio apparatus operable on receipt of a predetermined sequential tone code having at least first and second predetermined code signals, said battery saver circuit comprising:

receiver means for receiving tone modulated input signals and providing corresponding output tone signals in response thereto at a reference terminal;

power supply means coupled to said receiver means for selectively supplying operating power thereto;

detector means coupled to said receiver reference terminal for indicating a detection in response to said output tone signals having a predetermined frequency; and

control means coupled to said power supply means and said detecting means for selectively controlling the same;

said control means including,

first circuit means for enabling said power supply means to periodically supply operating power to said receiver means for a first predetermined time duration and for effecting the selection of a first frequency code signal that said detector means will respond to,

second circuit means for enabling said power supply means to supply operating power to said receiver means for a second time duration subsequent to and in response to said first frequency code signal being detected during said first time duration and for supplying power to said receiver means for a third time duration subsequent to and in response to said first frequency code signal being detected during said second time duration, and

third circuit means for enabling said power supply means to supply operating power to said receiver means for a fourth time duration and effecting the selection of a second frequency code signal subsequent to and in response to said first frequency code signal being detected during said third time duration, whereby said fourth time duration is at least long enough to permit detection of said second code signal and whereby power is supplied for said fourth time duration only after at least three detections of said first code signal.

27. A battery saver circuit as claimed in claim 26 wherein said second and third time durations are at most substantially the same duration as said first time duration and wherein said fourth time duration is substantially larger than said first time duration.

28. A battery saver circuit as claimed in claim 27 wherein said first time duration is 52 milliseconds, said second and third time durations are 42 milliseconds and said fourth time duration is 1.146 seconds.

29. A battery saver circuit as claimed in claim 26 in which said control means includes fourth circuit means for enabling said power supply means to supply operating power to said receiver means for a fifth time duration and effecting the selection of a third frequency code signal subsequent to and in response to said second frequency code signal being detected during said fourth time duration.