WO1992008214A1 - Selective call receiver having an energy conserving audible alert - Google Patents
Selective call receiver having an energy conserving audible alert Download PDFInfo
- Publication number
- WO1992008214A1 WO1992008214A1 PCT/US1991/007409 US9107409W WO9208214A1 WO 1992008214 A1 WO1992008214 A1 WO 1992008214A1 US 9107409 W US9107409 W US 9107409W WO 9208214 A1 WO9208214 A1 WO 9208214A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- alert signal
- threshold
- selective call
- energy source
- determined
- Prior art date
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Classifications
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B3/00—Audible signalling systems; Audible personal calling systems
- G08B3/10—Audible signalling systems; Audible personal calling systems using electric transmission; using electromagnetic transmission
- G08B3/1008—Personal calling arrangements or devices, i.e. paging systems
- G08B3/1016—Personal calling arrangements or devices, i.e. paging systems using wireless transmission
- G08B3/1025—Paging receivers with audible signalling details
Definitions
- This invention relates generally to selective call receivers including but not limited to those selective call receivers capable of conserving energy to prolong battery life and provide an audible alerting scheme that facilitates energy conservation.
- Selective call receivers have historically provided an audible alert signal to indicate reception of a message.
- the provision of the alert signal when the battery is near the end of its operational life may so exhaust the battery that the selective call receiver is rendered inoperative, resulting in a lost message or data.
- some selective call receiver designers have opted to reduce the sound pressure level of the alert signal when the remaining energy in the battery is below a threshold. Typically, this is accomplished by reducing the amplitude of the alert signal.
- a reduced sound pressure level results in a reduce volume alert signal, which may be missed if ambient noise levels are sufficiently high.
- a sudden high current demand near the end of the battery's operational life may reduce the instantaneous battery voltage to a point where messages and data are lost, or the selective call receiver is rendered inoperative.
- a sudden voltage drop (and increased internal resistance) is all too common in contemporary atmospherically controlled batteries, which tend to fail rapidly once energy is depleted beyond a certain point.
- atmospherically controlled batteries offer the highest energy density currently available, their use in certain applications (such as selective call receivers) may be impracticable unless a technique is developed to permit a battery powered device to properly function without causing a sudden batteiy failure.
- a selective call receiver monitors its energy source and provides a signal which indicates when the energy source has an energy level below a threshold.
- an alert signal having a first duty cycle is provided to indicate message reception when the energy level of the energy source is above the threshold.
- an alert signal having a second duty cycle is provided to indicate message reception.
- FIG.1 is a bock diagram of a selective call receiver suitable for use with the present invention.
- FIGs.2A thru 2D are illustrations of alert signals in accordance with the present invention.
- a selective call receiver 100 routes signals recovered by an antenna 102 to a receiver 104, which demodulates and recovers control information and messages via any suitable conventional process.
- the received control information e.g., selective call receiver addresses
- messages are processed by control circuitry 106.
- the control circuitry 106 operates to alert the user of the selective call receiver 100 that he or she has been "paged" (i.e., their address(es) was detected).
- the control circuitry 106 operates to provide one or more alert signals that activate or drive various alerting devices.
- a visual alert 116 may comprise a light emitting diode.
- a silent alert 114 may be provided by a conventional vibrator arrangement.
- An audible alert 120 may be generated via a transducer or speaker.
- one or more of these alerts are selectively activated via operation of user input controls 110.
- a corresponding alert may be presented to the user of the selective call receiver 100 to indicate the selection.
- all the alert devices receive an alert signal.
- the same alert signal could be provided to each alerting device, since only those alerting devices selectively activated by the user would respond to the alert signal.
- Messages addressed to the selective call receiver 100 are stored in a memory 118 so that the user may recall the message at his or her convenience.
- conventional user input controls e.g., read, delete, print, lock, etc.
- the control circuity 106 may be operated to cause the control circuity 106 to present the received message on a display 112.
- the instrumentality used to present the received message will vary depending upon the type of message information received (i.e., numeric, alphanumeric, or graphical information presented on a display, voice information presented via a speaker, etc.).
- the preferred selective call receiver 100 is battery (108) powered. Accordingly, it is customary for the selective call receiver 100 to take prudent energy conservation steps so as to maximize the battery's operational lifetime. To do this, it is known to periodically temporarily deactivate some or all of the receiver 104, control circuitry 106, display 112, and other components of the selective call receiver 100. Preferably, this energy saving operation is executed continually during normal selective call receiver operation. However, the preferred selective call receiver 100 also includes a battery monitor 122, which operates in a known manner to inform the control circuitry 106 when the battery's capacity is below a threshold level.
- the control circuitry 106 of the present invention operates to inform the user of the battery's limited lifetime (such as via the display 112), and takes additional energy saving steps as will become hereinafter more fully appreciated.
- An optional timer 124 provides a timekeeping function for the selective call receiver 100. Besides providing a time-of-day clock function and calendar date function, the optional timer 124 may assist the control circuitry 106 in conserving energy by providing a flexible timebase from which to control a duty cycle for the alert signal. Moreover, by controlling the "ON" and "OFF times within the alert signal duty cycle, the control circuitry 106, aided by the optional timer 124, is capable of reducing the energy drain from the battery 108.
- a change in the alert signal duty cycle may serve to prolong battery life. Further, the new duty cycle may prolong the battery life while substantially maintaining a similar alert cadence (pattern) as before the "low” battery condition was detected.
- the selective call receiver 100 continues to provide the "familiar" alert cadences while attempting to conserve energy, as will be subsequently more fully discussed.
- the audible alert signal of FIG. 2A is generated under normal operating conditions. That is, so long as the batteiy (108) capacity remains above the decision threshold of the monitor 122.
- the preferred alert is provided at a frequency of 3.2 kHz with substantially a fifty per-cent duty cycle 202 for approximately eight seconds, unless earlier terminated by the user's operation of the user input controls 110.
- the alert signal is preferably adapted so as to provide an effective alert signal, while conserving more energy than for the alert signal of FIG.2A.
- the present invention prefers to adapt the duty cycle of the alert signal from the approximate fifty per-cent duty cycle 122 (i.e. ; ON and OFF for 1 /2 period) (see FIG.2 A) to an approximately twelve per-cent duty cycle 212 (i.e, ON for 1/8 period and OFF for 7/8 period) (see FIG. 2B).
- a full amplitude alert is provided for the full alert duration (preferably eight seconds) without changing the alert cadence (pattern).
- the adapted alert is generally perceived by the user as a repeating "chirp" instead of the normal "beep" sound commonly attributed to selective call receivers.
- the selective call receiver 100 may provide an optimal energy drain of an atmospherically controlled (e.g., zinc-air) battery that is near the end of its battery's operational life. Additionally, the "familiar" cadence (pattern) provides continued "user friendly" operation of the alert signals.
- an atmospherically controlled (e.g., zinc-air) battery that is near the end of its battery's operational life.
- the "familiar" cadence (pattern) provides continued "user friendly" operation of the alert signals.
Abstract
A selective call receiver (100) monitors an energy level of its energy source (108) relative to a threshold. When the selective call receiver (100) receives a message, an alert signal is provided to indicate message reception. The alert signal has a first duty cycle (202) when the energy level of the energy source is determined to be above the threshold. When the energy level of the energy source is determined to be below the threshold, the alert signal has a second duty cycle (212).
Description
SELECTIVE CALL RECEIVER HAVING AN ENERGY CONSERVING AUDIBLE ALERT
Field of the Invention
This invention relates generally to selective call receivers including but not limited to those selective call receivers capable of conserving energy to prolong battery life and provide an audible alerting scheme that facilitates energy conservation.
Background of the Invention
Selective call receivers (e.g., pagers) have historically provided an audible alert signal to indicate reception of a message. However, since most selective call receivers are battery powered, the provision of the alert signal when the battery is near the end of its operational life may so exhaust the battery that the selective call receiver is rendered inoperative, resulting in a lost message or data. To solve this problem, some selective call receiver designers have opted to reduce the sound pressure level of the alert signal when the remaining energy in the battery is below a threshold. Typically, this is accomplished by reducing the amplitude of the alert signal. However, a reduced sound pressure level results in a reduce volume alert signal, which may be missed if ambient noise levels are sufficiently high. Accordingly, other selective call receiver designers have decided to maintain the sound pressure level of the alert signal, but reduce the total time duration of the alert. While this approach tends to conserve energy near the end of battery life, it does suffer a determent in that a large current demand is temporarily placed on the battery to provide the alert signal at full volume.
In certain batteries, such as contemporary atmospherically controlled (e.g., zinc-air) batteries, a sudden high current demand near the end of the battery's operational life may reduce the instantaneous battery voltage to a point where messages and data are lost, or the selective call receiver is
rendered inoperative. Regrettably, such a sudden voltage drop (and increased internal resistance) is all too common in contemporary atmospherically controlled batteries, which tend to fail rapidly once energy is depleted beyond a certain point. Thus, although atmospherically controlled batteries offer the highest energy density currently available, their use in certain applications (such as selective call receivers) may be impracticable unless a technique is developed to permit a battery powered device to properly function without causing a sudden batteiy failure.
Summary of the Invention
Briefly, according to the invention, a selective call receiver monitors its energy source and provides a signal which indicates when the energy source has an energy level below a threshold. When the selective call receiver receives a message, an alert signal having a first duty cycle is provided to indicate message reception when the energy level of the energy source is above the threshold. When the energy level of the energy source is below the threshold, an alert signal having a second duty cycle is provided to indicate message reception.
Brief Description of the Drawings
FIG.1 is a bock diagram of a selective call receiver suitable for use with the present invention. FIGs.2A thru 2D are illustrations of alert signals in accordance with the present invention.
Description of a Preferred Embodiment
Referring to FIG. 1, a selective call receiver 100 routes signals recovered by an antenna 102 to a receiver 104, which demodulates and recovers control information and messages via any suitable conventional process. The received control information (e.g., selective call receiver addresses) and messages are processed by control circuitry 106. When a received address substantially corresponds to one or more addresses
associated with the selective call receiver 100, the control circuitry 106 operates to alert the user of the selective call receiver 100 that he or she has been "paged" (i.e., their address(es) was detected). To do this, the control circuitry 106 operates to provide one or more alert signals that activate or drive various alerting devices. For example, a visual alert 116 may comprise a light emitting diode. A silent alert 114 may be provided by a conventional vibrator arrangement. An audible alert 120 may be generated via a transducer or speaker. Typically, one or more of these alerts are selectively activated via operation of user input controls 110. Additionally, upon selectively activating one or more of the alerts via the user input controls 110, a corresponding alert may be presented to the user of the selective call receiver 100 to indicate the selection. Generally, it is common in the industry to operate the visual alert together with either the audible alert or the silent alert. As can be seen in FIG. 1, all the alert devices receive an alert signal. Optionally, of course, the same alert signal could be provided to each alerting device, since only those alerting devices selectively activated by the user would respond to the alert signal.
Messages addressed to the selective call receiver 100 are stored in a memory 118 so that the user may recall the message at his or her convenience. Toward this end, conventional user input controls (e.g., read, delete, print, lock, etc.) 110 may be operated to cause the control circuity 106 to present the received message on a display 112. Of course the instrumentality used to present the received message will vary depending upon the type of message information received (i.e., numeric, alphanumeric, or graphical information presented on a display, voice information presented via a speaker, etc.).
As is conventional, the preferred selective call receiver 100 is battery (108) powered. Accordingly, it is customary for the selective call receiver 100 to take prudent energy conservation steps so as to maximize the battery's operational lifetime. To do this, it is known to periodically temporarily deactivate some or all of the receiver 104, control circuitry 106, display 112, and other components of the selective call receiver 100. Preferably, this energy saving operation is executed continually during normal selective call receiver operation. However, the preferred selective call receiver 100 also includes a battery monitor 122, which operates in a
known manner to inform the control circuitry 106 when the battery's capacity is below a threshold level. When this happens, the control circuitry 106 of the present invention operates to inform the user of the battery's limited lifetime (such as via the display 112), and takes additional energy saving steps as will become hereinafter more fully appreciated. An optional timer 124 provides a timekeeping function for the selective call receiver 100. Besides providing a time-of-day clock function and calendar date function, the optional timer 124 may assist the control circuitry 106 in conserving energy by providing a flexible timebase from which to control a duty cycle for the alert signal. Moreover, by controlling the "ON" and "OFF times within the alert signal duty cycle, the control circuitry 106, aided by the optional timer 124, is capable of reducing the energy drain from the battery 108. Therefore, under a "low" battery condition, such as when the monitor 122 detects that the battery energy level is below a threshold, a change in the alert signal duty cycle may serve to prolong battery life. Further, the new duty cycle may prolong the battery life while substantially maintaining a similar alert cadence (pattern) as before the "low" battery condition was detected. Hence, the selective call receiver 100 continues to provide the "familiar" alert cadences while attempting to conserve energy, as will be subsequently more fully discussed.
Referring to FIG. 2A, an illustration of an alert signal suitable for use with the audible alert of FIG. 1 is shown. Preferably, the audible alert signal of FIG. 2A is generated under normal operating conditions. That is, so long as the batteiy (108) capacity remains above the decision threshold of the monitor 122. Although not shown to scale, the preferred alert is provided at a frequency of 3.2 kHz with substantially a fifty per-cent duty cycle 202 for approximately eight seconds, unless earlier terminated by the user's operation of the user input controls 110. However, when the monitor 122 determines that the remaining battery (108) capacity is below the threshold, the alert signal is preferably adapted so as to provide an effective alert signal, while conserving more energy than for the alert signal of FIG.2A. To do this, the present invention prefers to adapt the duty cycle of the alert signal from the approximate fifty per-cent duty cycle 122 (i.e.; ON and OFF for 1 /2 period) (see FIG.2 A) to an approximately
twelve per-cent duty cycle 212 (i.e, ON for 1/8 period and OFF for 7/8 period) (see FIG. 2B). In this way, a full amplitude alert is provided for the full alert duration (preferably eight seconds) without changing the alert cadence (pattern). The adapted alert is generally perceived by the user as a repeating "chirp" instead of the normal "beep" sound commonly attributed to selective call receivers. In this way, the user is simultaneously provided with an audible alert of a low battery condition (in addition to any displayed message that may be presented). This practice is preferred over prior techniques of reducing the alert time, or reducing the alert amplitude which may not provide an effective alert in noisy environments. Of course, the techniques of the present invention could be incorporated with the known practices to reduce the amplitude (see FIG.2C) 222 or to reduce the alert time (see FIG.2D) 232 of the present invention's adaptive duty cycle alert. Therefore, by implementing the aforementioned inventive arrangement and steps, the selective call receiver 100 may provide an optimal energy drain of an atmospherically controlled (e.g., zinc-air) battery that is near the end of its battery's operational life. Additionally, the "familiar" cadence (pattern) provides continued "user friendly" operation of the alert signals.
Claims
1. A selective call receiver, comprising: receiver means, selectively coupled to an energy source, for receiving a message; means for providing an alert signal to indicate message reception, the alert signal having a first duty cycle when the energy source is determined to have an energy level above a threshold, and the alert signal having a second duty cycle when the energy source is determined to have an energy level below the threshold.
2. The selective call receiver of claim 1, including energy conservation means for selectively rendering at least a portion of the receiver means inoperative.
3. The selective call receiver of claim 1, including display means coupled to the receiver means for displaying the received message.
4. The selective call receiver of claim 1, including a memory coupled to the receiver means for storing the received message.
5. The selective call receiver of claim 1, wherein the means for providing an alert signal provides an alert signal having a substantially fifty per-cent duty cycle when the energy level of the energy source is determined to be above the threshold, and provides an alert signal having a duty cycle less than fifty per-cent when the energy level of the energy source is determined to be below the threshold.
6. The selective call receiver of claim 5, wherein the alert signal has an approximately twelve per-cent- duty cycle when the energy level of the energy source is determined to be below the threshold.
7. The selective call receiver of claim 5, including means for reducing the alert signal's amplitude when the energy level of the energy source is determined to be below the threshold.
8. The selective call receiver of claim 1, including means for reducing the alert signal's amplitude when the energy level of the energy source is determined to be below the threshold.
9. The selective call receiver of claim 8, including means for reducing the alert signal's duration when the energy level of the energy source' is determined to be below the threshold.
10. The selective call receiver of claim 1, including means for reducing the alert signal's duration when the energy level of the energy source is determined to be below the threshold.
11. The selective call receiver of claim 1, including timekeeping means for providing an indication of time.
12. The selective call receiver of claim 1, including means for providing a silent alert in response to the alert signal to indicate reception of a message.
13. The selective call receiver of claim 1, including means for providing a visual alert in response to the alert signal to indicate reception of a message.
14. The selective call receiver of claim 1, including means for providing an audible alert in response to the alert signal to indicate reception of a message.
15. The selective call receiver of claim 1, further comprising a user input control coupled to the means for providing an alert signal to indicate detection of a user input control state, the alert signal having a first duty cycle when the energy source is determined to have an energy level above the threshold, and the alert signal having a second duty cycle when the energy source is determined to have an energy level below the threshold.
16. A selective call receiver, comprising: monitoring means for monitoring an energy source, and for providing a signal indicative of the energy source having an energy level below a threshold; receiver means, selectively coupled to the energy source, for receiving a message; alert means, responsive to the monitoring means, for providing an alert signal to indicate message reception, the alert signal having a first duty cycle when the energy source is determined to have an energy level above a threshold, and the alert signal having a second duty cycle when the energy source is determined to have an energy level below the threshold.
17. The selective call receiver of claim 16, including energy conservation means for selectively rendering at least a portion of the receiver means inoperative.
18. The selective call receiver of claim 16, including display means coupled to the receiver means for displaying the received message.
19. The selective call receiver of claim 16, including a memory coupled to the receiver means for storing the received message.
20. The selective call receiver of claim 16, wherein the means for providing an alert signal provides an alert signal having a substantially fifty per-cent duty cycle when the energy level of the energy source is determined to be above the threshold, and provides an alert signal having a duty cycle less than fifty per-cent when the energy level of the energy source is determined to be below the threshold.
21. The selective call receiver of claim 20, wherein the alert signal has an approximately twelve per-cent duty cycle when the energy level of the energy source is determined to be below the threshold.
22. The selective call receiver of claim 20, including means for reducing the alert signal's amplitude when the energy level of the energy source is determined to be below the threshold.
23. The selective call receiver of claim 16, including means for reducing the alert signal's amplitude when the energy level of the energy source is determined to be below the threshold.
24. The selective call receiver of claim 23, including means for reducing the alert signal's duration when the energy level of the energy source is determined to be below the threshold.
25. The selective call receiver of claim 16, including means for reducing the alert signal's duration when the energy level of the energy source is determined to be below the threshold.
26. The selective call receiver of claim 16, including timekeeping means for providing an indication of time.
27. The selective call receiver of claim 16, including means for providing a silent alert in response to the alert signal to indicate reception of a message.
28. The selective call receiver of claim 16, including means for providing a visual alert in response to the alert signal to indicate reception of a message.
29. The selective call receiver of claim 16, including means for providing an audible alert in response to the alert signal to indicate reception of a message.
30. The selective call receiver of claim 16, further comprising a user input control coupled to the means for providing an alert signal to indicate detection of a user input control state, the alert signal having a first duty cycle when the energy source is determined to have an energy level above the threshold, and the alert signal having a second duty cycle when the energy source is determined to have an energy level below the threshold.
31. A method for providing an alert signal, comprising the steps of: receiving a message; and providing a message reception indicating alert signal having a first duty cycle when an energy level of an energy source is determined to be above a threshold, and providing a message reception indicating alert signal having a second duty cycle when the energy level of the energy source is determined to be below the threshold.
32. The method of claim 31, further including the steps of: detecting a user input control state; and providing an alert signal to indicate detection of a user input control state, the alert signal having a first duty cycle when an energy level of an energy source is determined to be above the threshold, and the alert signal having a second duty cycle' when the energy level of the energy source is determined to be below the threshold.
33. The method of claim 32, wherein the step of providing an alert signal to indicate detection of a user input control state includes the step of: reducing the alert signal's amplitude when the energy level of the energy source is determined to be below the threshold.
34. The method of claim 31, wherein the step of providing a message reception indicating alert signal includes the step of: reducing the message reception indicating alert signal's amplitude when the energy level of the energy source is determined to be below the threshold.
35. A selective call receiver, comprising: monitoring means for monitoring an energy source, and for providing a signal indicative of the energy source having an energy level below a threshold; receiver means, selectively coupled to the energy source, for receiving a message; display means coupled to the receiver means for displaying the received message; a user input control for receiving user input control requests; and alert means, responsive to the monitoring means, for providing an audible alert signal to indicate message reception and to indicate a user input control state, the audible alert signal having a first duty cycle and a first amplitude when the energy level of the energy source is determined to be above the threshold, and the audible alert signal having a second duty cycle and a second amplitude when the energy level of the energy source is determined to be below the threshold.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US60426190A | 1990-10-29 | 1990-10-29 | |
| US604,261 | 1990-10-29 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO1992008214A1 true WO1992008214A1 (en) | 1992-05-14 |
Family
ID=24418881
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/US1991/007409 WO1992008214A1 (en) | 1990-10-29 | 1991-10-07 | Selective call receiver having an energy conserving audible alert |
Country Status (1)
| Country | Link |
|---|---|
| WO (1) | WO1992008214A1 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5703572A (en) * | 1993-07-14 | 1997-12-30 | Nec Corporation | Informing device for a radio receiver |
| WO2009064524A1 (en) * | 2007-11-13 | 2009-05-22 | Sony Ericsson Mobile Communications Ab | Automatic reduced audio low battery warning |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4155082A (en) * | 1976-11-16 | 1979-05-15 | Ian C. Jones and Leonard G. McDowell | Electrical connectors including power failure warning means |
| US4755816A (en) * | 1986-10-29 | 1988-07-05 | Motorola Inc. | Battery saving method for a selective call radio paging receiver |
| US4897835A (en) * | 1985-11-27 | 1990-01-30 | At&E Corporation | High capacity protocol with multistation capability |
| US4965569A (en) * | 1987-06-30 | 1990-10-23 | Motorola, Inc. | Digitized stored voice paging receiver |
-
1991
- 1991-10-07 WO PCT/US1991/007409 patent/WO1992008214A1/en unknown
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4155082A (en) * | 1976-11-16 | 1979-05-15 | Ian C. Jones and Leonard G. McDowell | Electrical connectors including power failure warning means |
| US4897835A (en) * | 1985-11-27 | 1990-01-30 | At&E Corporation | High capacity protocol with multistation capability |
| US4755816A (en) * | 1986-10-29 | 1988-07-05 | Motorola Inc. | Battery saving method for a selective call radio paging receiver |
| US4965569A (en) * | 1987-06-30 | 1990-10-23 | Motorola, Inc. | Digitized stored voice paging receiver |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5703572A (en) * | 1993-07-14 | 1997-12-30 | Nec Corporation | Informing device for a radio receiver |
| CN1052086C (en) * | 1993-07-14 | 2000-05-03 | 日本电气株式会社 | Call informing device for a radio receiver |
| WO2009064524A1 (en) * | 2007-11-13 | 2009-05-22 | Sony Ericsson Mobile Communications Ab | Automatic reduced audio low battery warning |
| US7870410B2 (en) | 2007-11-13 | 2011-01-11 | Sony Ericsson Mobile Communications Ab | Automatic reduced audio low battery warning |
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