(12) United States Patent
`Tiwari
`
`(10) Patent No.:
`(45) Date of Patent:
`
`US 7,359,713 B1
`Apr. 15, 2008
`
`USOO7359713B1
`
`(54) BATTERY CONSUMPTION OPTIMIZATION
`FOR MOBILE USERS
`
`(75) Inventor: Anil Tiwari, Palo Alto, CA (US)
`O
`O
`(73) Assignee: timely Limited,
`unny Vale,
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 192 days.
`(21) Appl. No.: 10/377.563
`
`y x- - -
`
`9
`
`(*) Notice:
`
`2001/0044312 A1 * 1 1/2001 Yamane ...................... 455,456
`2002fOOO2599 A1
`1/2002 Arner et al.
`2002fOO13815 A1
`1/2002 Obradovich et al.
`2002-0042266 A 42002 Heyward et al.
`2002fOO65698 A1
`5, 2002 Schicket al.
`2002/O124.065 A1
`9, 2002 Barritt et al.
`2002fO184200 A1 12/2002 Ueda et al.
`2003/0.104849 A1* 6/2003 Arimitsu ..................... 455,574
`2003/O115O19 A1* 6, 2003 Doddek et al. ...
`... 702, 183
`loosoooos Ai: 7.200s Niwat al... 455,456
`2004/00 14478 A1
`1/2004 Hoffman et al. ......... 455,456.1
`2004/0204184 A1 * 10/2004 Lin ............................ 455,574
`FOREIGN PATENT DOCUMENTS
`WO PCT/USOO.27749
`4/2001
`WO
`WO O1 (26288 A1
`4/2001
`WO PCT/USO1, 19532
`12/2001
`WO
`WO O1 (96906 A1 12/2001
`(51) Int. Cl.
`WO PCT/USO1/22686
`2, 2002
`(2006.01)
`H04O 7/20
`WO
`WO O2,10939 A1
`2/2002
`(52) U.S. Cl. ............................... 455/456.1:455/456.6;
`* cited by examiner
`455/571; 455/572; 455/573; 455/574; 342/357.01;
`Pri
`E
`William T
`342/105; 342/106; 342/113: 342/114
`(58) Field of Classification Search .. 455/4.56.1-456.6, AC, i.O. s: rOSt
`455/571-574; 340/988: 342/357.01, 105,
`SSIS OF EXOFife
`10
`CZ
`342/106, 113, 114
`See application file for complete search history.
`
`(22) Filed:
`
`Feb. 28, 2003
`
`(56)
`
`References Cited
`U.S. PATENT DOCUMENTS
`
`9. E. al, 1
`E. f ck
`eIVlay et al. ...........
`4. W I
`3, 2002 Razavi et al.
`6,362,730 B2
`6/2002 Sheynblat et al. .......... 455,574
`6,408,196 B2 *
`6,810,325 B2 * 10/2004 Amano et al. .............. 7O1/2O7
`2001/0033225 A1 10, 2001 Razavi et al.
`
`340,686.1
`
`ABSTRACT
`(57)
`Systems and methods are disclosed to provide power man
`agement for a mobile communication device having a loca
`tion determination function. The frequency of the location
`determination function may be adjusted based on whether
`the mobile communication device is moving and may be
`ther adjusted based on battery Voltage or expected battery
`1C.
`
`25 Claims, 3 Drawing Sheets
`
`200
`
`UPDATERATE
`
`MOWING
`
`
`
`
`
`
`
`STOPPD
`204
`
`UpoAERAt
`IC8
`
`SLOW
`MOWING
`208
`
`GPSFX OrAFTER
`5 MINUTE TIMEOUT
`
`Apoxid
`C5
`
`
`
`APPAUNCED
`
`ICO
`
`
`
`APP-AUNCHE WHEN THEast stateapowerWN
`APPTERMINATED secAUSE OFoRAINEDBATERY
`
`: : Ort
`
`distance between stopped position and current position.
`distance moved in 3 minutes.
`
`Page 1 of 9
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`SAMSUNG EX-1203
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`

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`U.S. Patent
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`Apr. 15, 2008
`
`Sheet 1 of 3
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`US 7,359,713 B1
`
`1 100 O
`
`
`
`LOCATION
`DETERMINATION
`102.
`
`COMMUNICATION
`SYSTEM
`104.
`
`MICROPROCESSOR
`AND MEMORY
`106
`
`INPUT SYSTEM
`108
`
`DISPLAY SYSTEM
`110
`
`FIG. 1
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`Page 2 of 9
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`

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`U.S. Patent
`
`Apr. 15, 2008
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`Sheet 2 of 3
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`US 7,359,713 B1
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`2OO
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`UPDATE RATE
`
`
`
`
`
`
`
`
`
`
`
`STOPPED
`204
`
`UPDATE RATE
`C8
`
`
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`SLOW
`MOVING
`208
`
`
`
`C1
`
`
`
`
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`C2
`
`GPS FIXOR AFTER
`5 MINUTE TIMEOUT
`
`AEP EXITED
`
`APP LAUNCHED
`
`
`
`CO
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`APP LAUNCHED WHEN THE LAST STATE4 POWERDOWN
`(APPTERMINATED BECAUSE OF DRAINED BATTERY)
`C21
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`
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`214
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`D= 100m
`D = Distance between stopped position and current position.
`D = Distance moved in 3 minutes.
`
`FIG. 2
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`Page 3 of 9
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`U.S. Patent
`
`Apr. 15, 2008
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`Sheet 3 of 3
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`US 7,359,713 B1
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`
`
`
`
`
`
`
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`
`
`CHECK
`BATTERY LEVEL
`
`STOP SAMPLING GPS
`STOP TRANSMISSION
`NOTIFY USER
`310
`
`GPS SAMPLE RATE:
`STOP STATE = 15 MIN
`OTHER STATES = 5 MN
`312.
`
`
`
`GPS SAMPLE RATE
`STOP STATE = 1 MN
`OTHER STATES = 10 SEC
`314
`
`GPS Sample rate: Rate at which the application is asking GPS for location information
`V : Batter voltage threshold where the phone has very limited charge left
`V : Batter voltage threshold above which normal operation can take place
`
`FG. 3
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`Page 4 of 9
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`

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`1.
`BATTERY CONSUMPTION OPTIMIZATION
`FOR MOBILE USERS
`
`TECHNICAL FIELD
`
`The present invention relates generally to communication
`systems and, more particularly, to systems and methods for
`providing power management for a mobile communication
`device.
`
`BACKGROUND
`
`Mobile communication devices are well known and are
`utilized by individuals and businesses to communicate vari
`ous types of information. For example, mobile communica
`tion devices may include wireless telephones, personal digi
`tal assistants, or custom communication devices that can
`communicate via text and/or voice or other information over
`a wireless communication link. These mobile communica
`tion devices may also include location determination tech
`niques, such as for example via their cellular network or by
`utilizing satellite signals (e.g., global positioning system
`(GPS) satellites).
`The location determination technique that is incorporated
`into the mobile communication device allows for a variety
`of potential location-based applications. However, the
`mobile communication device usually has a limited amount
`of power available from its battery and frequent use of the
`location determination technique may quickly drain the
`battery. A conventional mobile communication device gen
`erally requires its user to monitor battery life and determine
`when to disable the location determination function to
`conserve battery life. This approach places the burden on the
`user and may result in poor power management. As a result,
`there is a need for systems and methods for providing power
`management for a mobile communication device utilizing a
`location determination technique.
`
`SUMMARY
`
`2
`monitor a state of the mobile device and control how often
`to determine the position of the mobile device.
`In accordance with another embodiment of the present
`invention, a method of providing power management to a
`mobile device having a location determination function
`includes determining whether the mobile device is stationary
`or moving; and controlling how often the location determi
`nation function is performed based on whether the mobile
`device is stationary or moving.
`The scope of the invention is defined by the claims, which
`are incorporated into this section by reference. A more
`complete understanding of embodiments of the present
`invention will be afforded to those skilled in the art, as well
`as a realization of additional advantages thereof, by a
`consideration of the following detailed description of one or
`more embodiments. Reference will be made to the appended
`sheets of drawings that will first be described briefly.
`
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`15
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`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIG. 1 shows a block diagram illustrating a mobile
`communication device in accordance with an embodiment
`of the present invention.
`FIG. 2 shows a block diagram illustrating a state machine
`for a mobile communication device in accordance with an
`embodiment of the present invention.
`FIG. 3 shows a flowchart for battery consumption opti
`mization in accordance with an embodiment of the present
`invention.
`The preferred embodiments of the present invention and
`their advantages are best understood by referring to the
`detailed description that follows. It should be appreciated
`that like reference numerals are used to identify like ele
`ments illustrated in one or more of the figures.
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`DETAILED DESCRIPTION
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`US 7,359,713 B1
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`40
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`45
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`Systems and methods are disclosed herein to provide
`power management for a mobile communication device. For
`example, in accordance with one embodiment of the present
`invention, a state machine monitors the movement (e.g.,
`position, Velocity, etc.) of the mobile communication device
`and adjusts the frequency of a location determination func
`tion based on the monitored movement. A battery state may
`also be monitored to further adjust the frequency of the
`location determination function to maximize battery life.
`More specifically, in accordance with one embodiment of
`50
`the present invention, a mobile communication device
`includes a location determination system adapted to receive
`location information for the mobile communication device;
`a communication system adapted to communicate through a
`wireless network; a microprocessor coupled to the location
`determination system and the communication system; and a
`state machine adapted to determine whether the mobile
`communication device is in a stopped state or a moving state
`and control how often the location information is obtained
`by the location determination system based on whether the
`mobile communication device is in the stopped State or the
`moving state.
`In accordance with another embodiment of the present
`invention, a mobile device includes a location determination
`system adapted to receive location information and deter
`mine a position of the mobile device; and a state machine
`coupled to the location determination system and adapted to
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`FIG. 1 shows a block diagram illustrating a mobile
`communication device 100 in accordance with an embodi
`ment of the present invention. Mobile communication
`device 100 includes a location determination system 102, a
`communication system 104, a microprocessor and memory
`106, an input system 108, and a display system 110.
`Location determination system 102 provides a location
`function for mobile communication device 100. For
`example, location determination system 102 may receive
`global positioning system (GPS) signals and determine a
`pseudorange to one or more satellites in order to determine
`the location of mobile communication device 100 or provide
`the pseudoranges via communication system 104 to an
`external device that determines the location from the pseu
`doranges. In this example, location determination system
`102 represents a GPS receiver that is integrated into mobile
`communication device 100.
`Alternatively, location determination system 102 may
`resolve location information based on signals (e.g., cellular
`signals) or information received by communication system
`104. Location determination system 102 may also resolve
`location, for example, by a combination of information
`received by communication system 104 (e.g., differential
`GPS information) along with information received through
`the GPS signals. However, generally, there must be specific
`circuitry or functions that may be periodically performed
`that could be selected or deselected, such that when dese
`lected results in savings in terms of power usage (e.g.,
`reduction in amount of battery power utilized).
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`Communication system 104 includes a transmitter and a
`receiver to communicate through a wireless network (e.g., a
`cellular network). Microprocessor and memory 106 include
`the core electronics that perform various desired functions
`and serve to link the various components of mobile com
`munication device 100. Input system 108 represents a device
`for inputting information into mobile communication device
`100. For example, input system 108 may represent a key
`board or a touchpad. Display system 110 is a display, Such
`as a liquid crystal display or other type of display for
`presenting information to a user of mobile communication
`device 100.
`Mobile communication device 100 may represent, for
`example, a wireless telephone (e.g., a cellphone), a two-way
`pager, a personal digital assistant, or other type of device that
`includes a location determination function (e.g., a GPS
`receiver) or is couplable to a location determination device.
`A typical example is a cell phone that incorporates a GPS
`receiver to provide the location determination function.
`Another example is a cell phone that provides the location
`determination function based on known cellular network
`techniques.
`It should also be understood that various techniques
`discussed herein in accordance with an embodiment of the
`present invention may be applicable to a mobile device
`25
`having solely a location determination function (i.e., com
`munication system 104 is not present). For example, the
`battery consumption optimization techniques may be appli
`cable to a mobile GPS receiver.
`FIG. 2 shows a block diagram illustrating a state machine
`200 for mobile communication device 100 in accordance
`with an embodiment of the present invention. State machine
`200 is a controller state diagram for monitoring the state of
`mobile communication device 100 and performing various
`functions based on the state. Specifically, state machine 200
`has five states, which include a power up state 202, a stopped
`state 204, a moving state 206, a slow moving state 208, and
`a power down state 210.
`Power up state 202 occurs when mobile communication
`device 100 is switched on (e.g., by a user to completely
`power up mobile communication device 100). Power up
`state 202 may be entered in a normal fashion, such as along
`a path 212 from power down state 210 (e.g., after a user
`switches off mobile communication device 100), or power
`up state 202 may be entered after shut down (along a path
`214) due to Some other condition, Such as for example due
`to a completely drained battery. From power down state 210
`to power up state 202 (path 212) or to power up state 202
`along path 214, various Software applications may be
`launched to provide or control various functions of mobile
`communication device 100.
`Optionally, an event code (or referred to as an invoke code
`(IC)) may be generated, such as ICO shown on path 212,
`which indicates that power has been applied to mobile
`communication device 100. The event code, for example,
`may be sent to a data processing station that monitors mobile
`communication device 100. If path 214 is taken to arrive at
`power up state 202, an event code (IC21) may be generated
`and possibly sent to the data processing station to indicate
`that an illegal or abnormal transition to power up state 202
`has occurred. Further details regarding event codes, moni
`toring, and communications between a data processing
`station and a mobile communication device may be found,
`for example, in U.S. patent application Ser. No. 10/377,575
`entitled “Dynamic Server Managed Profiles For Mobile
`Users' filed Feb. 28, 2003, which is incorporated herein by
`reference in its entirety.
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`After power up has completed, a transition from power up
`state 202 to stopped state 204 occurs. This transition may
`occur after a location determination has been made (e.g., a
`GPS fix) or after a certain time period has passed (e.g., a five
`minute timeout). Optionally, an event code (IC1) may be
`generated and sent to the data processing station to indicate
`a transition from power up to stopped has occurred.
`During stopped state 204, moving state 206, and slow
`moving state 208, the location determination function (e.g.,
`a GPS fix) is being performed at a certain frequency (i.e., a
`certain time interval or a certain rate) to obtain location and
`velocity information. The frequency of the location deter
`mination function may differ depending upon the state of
`mobile communication device 100.
`For example, if mobile communication device 100 is in
`stopped State 204, the location determination function may
`be performed at a much lower frequency relative to when
`mobile communication device 100 is in slow moving state
`208. Similarly, if mobile communication device 100 is in
`slow moving state 208, the location determination function
`may be performed at a lower frequency relative to when
`mobile communication device 100 is in moving state 206,
`because the location of mobile communication device 100 is
`changing at a slower rate.
`By monitoring the state of mobile communication device
`100 (e.g., stopped, slow moving, or moving), it can be
`determined how often a location determination should be
`performed to provide adequate tracking and monitoring of
`mobile communication device 100. Furthermore, by adjust
`ing the frequency of the location determination function,
`battery power may be conserved by preventing unnecessary
`location determinations, such as when mobile communica
`tion device 100 is stopped or moving slowly.
`Consequently, the location determination function may be
`performed, for example, at a first rate, a second rate, and a
`third rate, depending upon whether mobile communication
`device 100 is in stopped state 204, slow moving state 208,
`or moving state 206, respectively. As an example, the first
`rate, the second rate, and the third rate may be set to one
`minute, thirty seconds, and 5 seconds, respectively. Thus, if
`mobile communication device 100 is in stopped state 204,
`then for example a GPS fix will occur every minute.
`However, if mobile communication device 100 is in slow
`moving state 208 or moving state 206, then for example a
`GPS fix will occur every thirty seconds or every five
`seconds, respectively. Thus, by monitoring the States of
`mobile communication device 100, battery power may be
`conserved and needless location determinations may be
`avoided, while maintaining adequate tracking or location
`determination of mobile communication device 100.
`It should be understood that more states may be added to
`further refine the amount of movement that each state
`covers. For example, another state may be added (e.g., fast
`moving) to more adequately cover the expected degree of
`movement. Alternatively, the number of states may be
`reduced, depending upon the application (e.g., allow only
`stopped and moving states). Furthermore, the frequency of
`the location determination function may be adjusted depend
`ing upon the intended application and the desired location
`determination accuracy.
`As shown in FIG. 2, the transition from one state to the
`next may be determined based on a velocity of or a distance
`traveled by mobile communication device 100. For example,
`the transition from stopped state 204 to moving state 206
`may occur if mobile communication device 100 has a
`velocity (V) greater than a threshold velocity (V). The
`threshold velocity, for example, may be set to 5 k/h (kilo
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`5
`meters/hour). Alternatively, the transition from stopped state
`204 to moving state 206 may occur if mobile communica
`tion device 100 has moved a distance (D), between the
`previously recorded stopped position and the current posi
`tion, greater than a threshold distance (D). The threshold
`distance (D), for example, may be set to 100 m (meters).
`Optionally, an event code (IC5), as discussed above, may be
`generated and sent indicating the transition or marking, for
`example, a starting point from the stopped position.
`If the velocity (V) drops below the threshold velocity
`(V), a transition from moving state 206 to slow moving
`state 208 occurs. Similarly, if the velocity (V) rises above the
`threshold Velocity (V), a transition from slow moving State
`208 to moving state 206 occurs.
`The distance traveled may also be monitored while in
`slow moving state 208. If a distance (D) traveled over a
`certain time period (e.g., three minutes) is greater than the
`threshold distance (D), then mobile communication device
`100 remains in slow moving state 208 (assuming velocity
`requirements discussed above are also met). If the distance
`(D) drops below the threshold distance (D), then a tran
`sition from slow moving state 208 to stopped state 204
`occurs. Optionally, an event code (IC2), as discussed above,
`may be generated and sent indicating to the data processing
`station that a transition from slow moving to stopped has
`occurred.
`It should be noted that the various parameters, such as the
`threshold distance (D), the threshold velocity (V), the
`distance (D), and the distance (D) may be set or adjusted
`by a user based on the intended application or expected
`conditions for mobile communication device 100. These
`parameters may also be set or modified, for example, Solely
`by the data processing station, which communicates this
`information (e.g., within a profile) to mobile communication
`device 100 as described in U.S. patent application entitled
`“Dynamic Server Managed Profiles For Mobile Users'
`referenced herein.
`During slow moving state 208, moving state 206, and
`possibly stopped State 204, the state of mobile communica
`tion device 100 may be communicated at a certain rate or at
`certain time intervals to the data processing station in a
`similar manner as when communicating the event codes.
`This is designated in an exemplary manner by an event code
`(IC8), which indicates an update to the data processing
`station, and labeled update rate for moving state 206 and
`slow moving state 208 in FIG. 2. The update rate or interval
`may be also set, for example, by a user or it may be set by
`the data processing station via the profile, as described in
`U.S. patent application entitled “Dynamic Server Managed
`Profiles For Mobile Users’ referenced herein.
`Power down state 210 may be entered, for example, when
`a user Switches off mobile communication device 100.
`Various software applications, for example, that were
`launched upon entering power up state 202 may be exited
`and optionally an event code (IC6) may be generated to
`indicate the power down condition or event.
`FIG. 3 shows a flowchart 300 for battery consumption
`optimization in accordance with an embodiment of the
`present invention. Flowchart 300 may be employed, for
`example, to complement state machine 200 (FIG. 2) to
`further adjust the location determination frequency based on
`measured or estimated battery Supply strength (e.g., amount
`of charge left or battery voltage level or reserve). Alterna
`tively, if state machine 200 is not employed, flowchart 300
`may be used separately to adjust the location determination
`frequency based on battery supply strength. Flowchart 300
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`may be implemented in circuitry or software executed by a
`microprocessor (e.g., microprocessor and memory 106 of
`FIG. 1).
`Step 302 checks or measures the battery voltage level
`(V). Step 302 is performed periodically (e.g., every sec
`ond). If the battery voltage level (V) is less than a first
`threshold voltage (V) at step 304, then step 310 prevents
`any further location determination attempts (e.g., GPS
`receiver location attempts are suspended or the GPS receiver
`is powered down). The first threshold Voltage (V) may, for
`example, be set to a value at which the battery has a very
`limited charge left or at which mobile communication
`device 100 has a very limited amount of operational time
`left. Additionally, the user of mobile communication device
`100 may be notified of the low battery condition and
`transmissions regarding the location of mobile communica
`tion device 100 (e.g., to the data processing station) may also
`be terminated or prevented from occurring.
`If the battery Voltage level (V) is greater than or equal
`to the first threshold voltage (V) and the battery voltage
`level (V) is less than the second threshold Voltage (V)
`at step 306, then step 312 modifies the location determina
`tion frequency (e.g., GPS sampling rate) to occur at a slower
`rate than when the battery has a full charge. The second
`threshold Voltage (V) may, for example, be set to a value
`at or above which normal operation can take place typically
`for a reasonable amount of time. The location determination
`frequency may, for example, be set to fifteen minutes when
`not moving (e.g., stopped State 204 in FIG. 2) or five minutes
`when moving (e.g., slow moving state 208 or moving State
`206 in FIG. 2). These values may be adjusted based on
`battery capacity and intended application and the degree of
`location determination accuracy required.
`If the battery Voltage level (V) is greater than or equal
`to the second threshold voltage (V) at step 308, then step
`314 sets the location determination frequency to occur at a
`desired rate for normal operation. The location determina
`tion frequency may, for example, be set to one minute when
`not moving or ten seconds when moving (e.g., slow moving
`state 208 or moving state 206 in FIG. 2). The threshold
`Voltages may be set, for example, based on a certain Voltage
`below a maximum voltage level (i.e., corresponding to a full
`battery charge) or based on a percentage from full charge.
`For example, the second threshold Voltage (V) may be set
`to one half (/2 or 50%) of a full charge and the first threshold
`Voltage (V) may be set to one eighth (/8 or 12.5%) of a
`full charge.
`In accordance with an embodiment of the present inven
`tion, battery consumption is optimized based on movement
`of the mobile communication device and available battery
`power. In normal operation, the GPS application running on
`the mobile communication device queries the GPS hardware
`for a fix (i.e., location estimate) at a specified frequency (i.e.,
`sampling rate or sampling interval. Such as for example
`specified in a profile or by a user). If the mobile communi
`cation device is moving rapidly, the GPS fix must occur at
`relatively frequent intervals (e.g., every fifteen seconds) as
`opposed to when it is stopped (e.g., GPS fix every three
`minutes). The position, for example, may also be transmitted
`to the data processing station at a given frequency or time
`interval (reporting interval, e.g., every fifteen minutes).
`Every time the GPS is queried for a position, a fix is
`attempted that uses energy and computation power. There
`fore, if the mobile communication device is not moving
`rapidly or if the battery is low, there is no need for frequent
`location determinations (e.g., GPS fixes) and the sampling
`rate may be reduced to conserve power.
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`On the other hand and depending upon the location
`determination technique, if rapid movement occurs and the
`last GPS fix is stale, additional power may be required to
`acquire a fix because the last fix is not sufficient to guide its
`current acquisition attempt. For example, a cold start (com
`pletely new acquisition) may require more energy than a
`warm start (acquisition that utilizes recent acquisition data).
`Therefore, the location determination must be frequent
`enough to allow rapid acquisition.
`In accordance with an embodiment of the present inven
`tion, a state machine (e.g., an intelligent state machine
`implemented in hardware or as a software application
`executed by a microprocessor) monitors the State of a mobile
`communication device (e.g., stopped, slow moving, moving,
`or fast moving) by utilizing location information. For
`example, location information may be provided by a GPS
`receiver integrated into the mobile communication device to
`provide position and Velocity. The application then adapts
`the usage of GPS to optimize the life of the mobile com
`munication device's battery based on the movement of the
`mobile communication device. The application (or another
`application) may further monitor the battery state and, if it
`is low, further reduce usage of GPS to maximize battery life
`or minimize battery usage.
`Embodiments described above illustrate but do not limit
`the invention. It should also be understood that numerous
`modifications and variations are possible in accordance with
`the principles of the present invention. Accordingly, the
`scope of the invention is defined only by the following
`claims.
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`4. The mobile communication device of claim 3, wherein
`the microprocessor monitors the level of charge of the
`battery of the mobile communication device by measuring a
`voltage level of the battery.
`5. The mobile communication device of claim 4, wherein
`the microprocessor prevents location information from
`being obtained by the location determination system when
`the voltage level of the battery is below a first voltage
`threshold, and the microprocessor reduces a frequency of
`obtaining the location information by the location determi
`nation system when the voltage level of the battery is at least
`equal to the first voltage threshold but below a second
`voltage threshold.
`6. The mobile communication device of claim 3, further
`comprising:
`an input system coupled to the microprocessor and
`adapted to receive information from a user of the
`mobile communication device; and
`a display System coupled to the microprocessor and
`adapted to provide information to a user of the mobile
`communication device.
`7. The mobile communication device of claim 1, wherein
`the state machine includes a stopped state, a slow moving
`state, and a moving state, the location information in the
`stopped state being obtained at a lower rate than for the slow
`moving state and the moving state.
`8. The mobile communication device of claim 7, wherein
`the state machine further includes a power down state and a
`power up state.
`9. The mobile communication device of claim 7, wherein
`a transition between the stopped state and the moving state
`is based on at least one of a Velocity and a distance
`parameter, a transition between the moving state and the
`slow moving state is based on a Velocity, and a transition
`between the slow moving state and the stopped state is based
`on a distance parameter.
`10. The mobile communication device of claim 1,
`wherein the mobile communication device comprises a
`wireless telephone, a pager, or a personal digital assistant.
`11. The mobile communication device of claim 1, wherein
`the wireless network is a cellular network.
`12. The mobile communication device of claim 1,
`wherein the mobile communication device, over the wireless
`network, notifies a data processing station of at least one of
`a transition from the stopped State to the moving State and
`from the moving state to the stopped state.
`13. The mobile communication device of claim 1,
`wherein at least one variable used by the state machine is
`provided by at least one of a user of the mobile communi
`cation device and a remote data processing station.
`14. A mobile device comprising:
`a location determination system adapted to receive rang
`ing signals and to determine a position of the mobile
`device based on the ranging signals;
`a battery coupled with the location determination system,
`the battery providing power to the location determina
`tion system; and
`a state machine coupled with the location determination
`system and adapted to (a) monitor (i) a state of the
`mobile device based on a change in position of the
`mobile device determined by the location determina
`tion system, and (ii) a level of charge in the battery; and
`(b) control a frequency at which the location determi
`nation system determines the position of the mobile
`device based on the state of the mobile device and the
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`I claim:
`1. A mobile communication device comprising:
`a communication system adapted to receive, over a wire
`less network, ranging signals for determining a geo
`graphical position of the mobile communication
`device;
`a location determination system coupled with the com
`munication system, the location determination system
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`adapted to receive the ranging signals and determine a
`geographical location of the mobile communication
`device;
`a battery coupled with the location determination system,
`the battery adapted to provide power to the mobile
`communication device; and
`a state machine coupled with the location determination
`system, the State machine adapted to (a) determine
`whether the mobile communication device is in a
`stopped State or a moving State based on a change in the
`geographical location of the mobile communication
`device, as determined by the location determination
`system; and (b) control a frequency at which the
`location determination system determines the geo
`graphical location based on (i) whether the mobile
`communication device is in the stopped state or the
`moving state and (ii) a level of charge stored in the
`battery, wherein the frequency comprises a first rate, a
`second rate, and a third rate of determining the geo
`graphical location.
`2. The mobile communication device of claim 1, wherein
`the location determination system is a global positioning
`system receiver.
`3. The mobile communication device of claim 1, wherein
`the communication device further comprises a microproces
`Sor, and wherein the state machine is implemented in Soft
`ware executed by the microprocessor.
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