GB2397972A

GB2397972A - Power saving in a foldable portable communication device

Info

Publication number: GB2397972A
Application number: GB0302105A
Authority: GB
Inventors: David Gaukrdoger
Original assignee: NEC Technologies UK Ltd
Current assignee: NEC Technologies UK Ltd
Priority date: 2003-01-29
Filing date: 2003-01-29
Publication date: 2004-08-04
Also published as: GB0302105D0

Abstract

A foldable portable communication device comprising a portable power supply, power level detection means, configuration detection means and control means. The control means is coupled to the power level detection means 32 and to the configuration detection means 30 and is configured to implement at least one power saving measure 36 if the power level falls below a threshold and the portable communication device is in the open configuration. The implementation of the power saving measure may additionally require detection of the absence of any command input to the device for a predetermined interval 42 and/or detection that the device is off-line. The power saving method can be the shutting off of the backlight of the LCD screen or shutting off the screen completely. The battery threshold level may be set to conserve enough power to make, for example, a ten minute phone call in the case of an emergency.

Description

PORTABLE COMMUNICATION DEVICE

FIELD OF THE INVENTION

This invention relates to a portable communication device of the type having a housing moveable between a stowed configuration for storage and an open configuration for operation of the mobile communication device and, in particular, to mobile telephones of that type. The invention relates to configurations of portable communication devices in which at least one power saving measure is implemented, for example, by switching the display and/or display backlight off, if the device is left in the open configuration and the power level falls below a threshold.

BACKGROUND OF THE INVENTION

In mobile telephones of the type in which the housing unfolds, or rotates, to reveal a display and allow use of the functionality of the mobile telephone, the mobile telephone is configured to keep the display on and the i mobile telephone fully operational for the entire time that the telephone is in the open configuration; the display is switched off when the telephone housing is moved to the stowed, or closed, configuration.

Mobile telephones require portable power supplies such as rechargeable batteries. Power saving techniques are employed in general in mobile telephones to conserve battery life and hence to prolong potential usage time.

It is the function of the power saving system of a mobile telephone to turn off as much of the phone's hardware as possible, in order to prolong battery life.

With a fold-phone, the main display remains turned on when the phone is open because it is not possible to tell when a user is reading the display. The display, and particularly the backlight for the display, are major consumers of a battery's energy.

SUMMARY OF THE INVENTION

We have appreciated that further improvements in power saving can be made in mobile telephones of the type having a housing moveable between a stowed, or closed, configuration and an open configuration in which the mobile telephone may be used. We have appreciated that a user may leave a fold-phone open accidentally and could be annoyed to return to find that they are unable to use it. On the other hand, the user may leave the phone open deliberately to view the screen, even though there is no activity which would necessitate other elements of the phone to remain on. It is, therefore, not possible to determine if the display and/or backlight should be left on and other functionality maintained from inactivity alone.

In particular, we have appreciated that if the telephone is left in the open configuration and the power level drops below a level sufficient to allow a predetermined interval of communication then reducing functionality and/or facilities, such as switching off the display and/or the backlight for the display, to conserve the remaining power is beneficial to the user. Should the user leave the telephone open accidentally, the telephone become accidentally opened, or the user leave the telephone open to read the display of, say, an entry in the address book, the display and/or backlight is automatically switched off to conserve a predetermined level of power. The telephone remains operable for say ten minutes of voice or data communication or use of another function at a later time when the user so desires. The exact duration of the operation will depend on the type of function used and environmental conditions but the telephone will be operational for a short period. Further power saving measures may be implemented. The mobile telephone functionality may be rendered inoperative until re-activated by the user, for example by closing and then re-opening the mobile telephone handset.

The invention is defined in the claims to which reference is now directed.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure l shows the type of mobile telephone employing the invention; Figure 2 shows the key functional components of a mobile telephone embodying the invention; Figure 3 is a flow-chart showing the operating steps of the power saving facility embodying the invention; Figure 4 shows an embodiment of the invention with additionally functionality provided by the inactivity detection means; and Figure 5 is a flow chart showing the operating steps of the power saving facility when the inactivity detection means is incorporated.

DESCRIPTION OF A PREFERRED EMBODIMENT

The embodiment of the invention is a mobile telephone of the type having a housing moveable between a stowed configuration, for storage of the mobile telephone in a non-operational state, and an open configuration in which the user can view the display, access the address book or other stored information, make or receive voice or data communications and other non-phone related tasks e.g. playing games. Figure l shows a mobile telephone of this type. Housings of this type are well-known to

the skilled man in this field.

The mobile telephone has additional functionality to monitor when the mobile telephone is in the open configuration and when the power level of the battery falls to a pre-determined threshold and to implement at least one power saving measure, for example switching off the display and/or backlight for the display, when both these conditions are met.

Figure 2 is a schematic diagram of the key functional elements required in the first embodiment of the invention. Additional elements are required to provide an operational mobile telephone. These additional

elements are well-known in the field of portable

communication devices and are not described here nor shown in figure 2.

A mobile telephone, or hand-held portable (HHP), lo of the type having a housing which is articulated and moveable between a closed, stowed position or configuration and an open configuration in which the display and key pad are presented to the user is provided with portable power supply means 20, in this case, a rechargeable battery removeably housed within the mobile telephone housing. Battery 20 is the sole power source for all components of the mobile telephone lO and is coupled to all components requiring power (not shown in figure 2). The mobile telephone lo is also provided with power level detection means 22 coupled to the battery 20. The power level detection means 22 take a quantitative measure relating to the amount of power available from the battery 20. Power level detection means 22 of this type are well-known.

The mobile telephone lo is provided with configuration detection means 24. In mobile telephones of this type, it is known to provide configuration detection means 24 to cause the display means 26, typically a liquid crystal display (LCD), to be switched off whenever the housing is moved to the stowed configuration. The functionality of the configuration detection means 24 for the telephone embodying the present invention is extended to generate a signal indicating when the housing is in the open configuration. This signal, in conjunction with a power level, is required by the control means 28. Display means 26 suitable for this type of mobile telephone lO are well-known to the skilled man.

Control means 28 provide the functionality necessary to make use of the invention. This functionality may be incorporated within a central processor unit (CPU) of the mobile telephone or may be provided in a separate processor. The functionality may be distributed. Power saving measures concerning software operations and those concerning hardware operations may be processed and implemented separately. Regardless of where the functionality of the control means is implemented, the effect of the control means is to implement one or more power saving measures when the prerequisite conditions are detected.

The control means 28 are coupled to the configuration detection means 24, display means 26 and power level detection means 22. The control means 28 and display means 26 require a power supply and this is provided by battery 20. For clarity, these and other power connections are not shown in figure 2.

As shown in flow chart figure 3, the control means 28 is configured to monitor whether or not the housing of the mobile telephone lO is in the open configuration 30 and to monitor the power level of the battery 32. If the power level has fallen below a pre-determined threshold and the mobile telephone lO is in the open configuration, the control means 28 is configured to implement a power saving measure for example by switching off the display 26 and/or backlight to the display to conserve what power is remaining. If the power level is above the threshold, the control means 28 continues to monitor both the configuration of the housing and the power level; no power saving measures are implemented by the control means 28. By switching off the display, we mean causing the display to blank and become inoperative whether by sending the appropriate control signal to the display or by interrupting the power supply to the display or by other appropriate means as dictated by the particular display chosen.

In addition to switching off the display backlight and/or the display, the power saving measure implemented by the control means 28 may cause the mobile telephone lO to be switched into a "deep-sleep" mode in which all non-essential function is suspended. In such a state, the mobile telephone lo uses the minimum power possible whilst maintaining its ability to be re-activated. For example, in the deep-sleep, or minimal power use, state the mobile telephone lO may maintain only a very slow clock, this being sufficient to re-activate the telephone lo at a later time upon detection of a suitable external stimulus.

The advantage obtained is that sufficient power is saved for at least minimal operation of the mobile telephone even if the phone is left open. Whilst this power saving implementation may result in a non-phone operation being suspended or terminated when the power level becomes low, the power so saved may be used for core activities such as data or voice communication. For example, play of a game may be terminated but power is retained in the telephone to make, say, ten minutes of data or voice communication. Should the need arise, the power retained would be sufficient to place a call to an emergency service.

An embodiment of the invention is also envisaged in which inactivity of the telephone is also monitored. In this second embodiment of the invention, the test applied to determine whether or not to implement the power saving measure is more sophisticated. Figure 4 shows a mobile telephone lO' additionally provided with inactivity detection means 40. Components with the same functionality as those of figure 2 are given the same reference numerals in figure 4 and are not described here.

Generally speaking, both fold-type and fixed body type mobile telephones are provided with means for monitoring activity of the telephone. Such means may monitor use of some or all of the non-phone related activities and some or all of the phone related activities. Such activity monitoring means may additionally be configured to report inactivity for example the absence of any command input and/or when the telephone is "off-line".

By command input we mean any input intended to convey an instruction to make the telephone function in the instructed manner and including recognised voice commands, such as "access address book", or key presses, such as entry of telephone number for subsequent dialling. By "off-line" we mean that the telephone is not actively involved in any transmission or reception to or from a network of, for example, data or voice communications.

The inactivity detection means 40 is coupled to the control means 28' and provides a signal or signals indicating whether or not the mobile telephone lO is off-line and whether or not any command input has been detected within the last specified interval of time.

The control means 28', in addition to the output of the configuration detection means 24 and the power level detection means 22, uses the output of the inactivity detection means 40 to determine whether or not to implement a power saving measure. It is deemed within the scope of the skilled man in the field of mobile telephones to provide a suitable inactivity detection means from the foregoing description and his knowledge

of this field.

As indicated in flow chart figure 5, the control means 28' is configured to monitor whether the housing is in the open configuration 30, monitor the power level of the battery 32 and to monitor whether any command input has been detected within, say, the last two minutes 42.

If the housing is in the open configuration and the power level of the battery has reached, or is below, the threshold and no command input has been detected in the specified period then the control means 28' implements at least one power saving measure to conserve the remaining power 36. The power saving measure or measures envisaged are the same as those described above with reference to figures 2 and 3. If the test conditions are not met then the control means does not implement any power saving measure. The control means continues to apply the relevant test based on the outputs from the power level detection means, configuration detection means and inactivity detection means. In addition to the requirements discussed in the preceding paragraph, the control means 28' may also require that the telephone is off-line before implementing the power saving measure or measures.

The invention is clearly applicable to portable communication devices other than mobile telephones and these are within the scope of the invention.

With respect to the above description, it is to be

realised that equivalent apparatus and methods are deemed readily apparent to one skilled in the art, and all equivalent apparatus and methods to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention. Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.

It should be noted that the features described by reference to particular figures and at different points in the description may be used in combinations other than those particularly described or shown. All such modifications are encompassed within the scope of the invention as set forth in the following claims.

Claims

1. A portable communication device of the type having a housing moveable between a stowed configuration and an open configuration, the portable communication device comprising: portable power supply means; power level detection means coupled to the portable power supply means; configuration detection means for detecting whether the portable communication device is in an open configuration; and control means, coupled to the power level detection means and configuration detection means, the control means configured to implement at least one power saving measure if the power level falls below a threshold and the portable communication device is in the open configuration.

2. A portable communication device according to claim 1, wherein the control means is configured with a threshold indicating a power level sufficient for a specified period of data communication.

3. A portable communication device according to claim 1, wherein the control means is configured with a threshold indicating a power level sufficient for a specified period of voice communication.

4. A portable communication device according to any of the preceding claims, wherein the control means is configured to switch off the portable communication device display backlight as a power saving measure.

5. A portable communication device according to any of the preceding claims, where the control means is configured to switch off the portable communication device display as a power saving measure.

6. A portable communication device according to any of the preceding claims, wherein the control means is configured to switch the portable communication device to a minimal power use state as a power saving measure.

7. A portable communication device according to any of claims 1 to 3, wherein the device further comprises inactivity detection means, coupled to the control means, the inactivity detection means being configured to detect the absence of any command input to the device for a predetermined interval and to cause the control means to switch off the display backlight as the power saving measure.

8. A portable communication device according to any of claims 1 to 3, wherein the device further comprises inactivity detection means, coupled to the control means, the inactivity detection means being configured to detect the absence of any command input for a predetermined interval and to cause the control means to switch off the display as the power saving measures.

9. A portable communication device according to any of claims 1 to 3, wherein the device further comprises inactivity detection means, coupled to the control means, the inactivity detection means being configured to detect the absence of any command input for a predetermined interval and to detect when the portable communication device is off-line and to cause the control means to switch the portable communication device to a minimal power use state.

10. A portable communication device according to any preceding claim in which the portable communication device is a mobile telephone.

A portable communication device substantially as hereinbefore described with reference to any of the accompanying drawings.

12. A method of configuring a portable communication device of the type having a housing moveable between a stowed configuration and an open configuration, the method comprising the steps of configuring the control means to: a) monitor the configuration of the housing of the portable communication device; b) monitor the power level of the power supply means powering the portable communication device; and c) implementing a power saving measure if the housing is in the open configuration and the power levels falls below a threshold.

13. A method according to claim 12, wherein step (c) causes the display backlight of the portable communication device to be switched off.

14. A method according to claim 12 or claim 13, wherein step (c) causes the display of the portable communication device to be switched off.

15. A method according to claim 12, wherein step (c) causes the portable communication device to be switched to a minimal power use state.

16. A method according to claim 12, the method further comprising the step of monitoring for an absence of any command inputs and wherein step (c) is modified such that implementation of the power saving measure additionally requires the absence of any command input for a predetermined interval.

17. A method according to claim 16, the method further comprising the step of monitoring for the device being off-line, and wherein step (c) is further modified such that implementation of the power saving measure additionally requires the device to be off-line.

18. A method substantially as hereinbefore described with reference to any of the accompanying drawings.