(19) Japanese Patent Office (JP) (12) Unexamined Patent Gazette (A) (11) Unexamined Patent Application
`(Kokai) No.: 2004-37116
`(P2004-37116A)
`(43) Publication Date: February 5, 2004
`Theme Code (Reference)
`5J062
`106A 5K067
`
`F1
`
`G01S 5/14
`H04B 7/26
`
`(51) Int. Cl.7
`G01S
`5/14
`H04Q 7/34
`
`(22) Filing Date:
`
`Request for Examination: Not Requested Number of Claims: 12 OL (14 Pages Total)
`(21) Application Number: Patent Application 2002-191213 (P2002-
`(71) Applicant: 000005832
`191213)
`Matsushita Electric Industrial Co., Ltd.
`June 28, 2002 (6/28/2002)
`1048 Oazakadoma, Kadoma-shi, Osaka
` 100087767
`Patent Attorney Keisei Nishikawa
` 100085604
`Patent Attorney Atsuo Mori
`(72) Inventor: Koji Sakamoto
`c/o Matsushita Electric Industrial Co., Ltd.
`1048 Oazakadoma, Kadoma-shi, Osaka
`(72) Inventor: Satake Sada
`c/o Matsushita Electric Industrial Co., Ltd.
`1048 Oazakadoma, Kadoma-shi, Osaka
`
`(74) Agent:
`
`(74) Agent:
`
`Continued on the back page
`(54) [Title of the Invention] Position information communication terminal and GPS positioning system
`
`(57) [Abstract]
`[Problem] To provide a position information communication
`terminal and GPS positioning system with which it is possible to
`flexibly switch between the normal sensitivity positioning mode in
`which the GPS receiver operates only when necessary and the high
`sensitivity positioning mode in which it always operates.
`[Solution Means]
`Through control of the power supply of the GPS receiver 10 by GPS
`control unit 12, each positioning operation is controlled of the
`normal sensitivity positioning mode in which the GPS receiver 10
`is operated only when necessary and the high sensitivity positioning
`mode in which the GPS receiver 10 is always operated, the latest
`orbit information of GPS satellites is obtained, the positioning
`control unit 13 switches between the normal sensitivity positioning
`mode and the high sensitivity positioning mode of the GPS receiver
`10, and the orbit information obtained via the network using the
`communication control unit 11 is supplied to the GPS control unit
`12.
`[Drawings]
`
`FIG. 1
`
`Battery cotrol
`unit
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`[Claims]
`[Claim 1]
`A position information communication terminal, provided with a GPS receiver that receives GPS satellite signals
`from GPS satellites and performs positioning operations; a communication control unit having a mobile
`communication means; a GPS control unit having an orbit information acquisition means for acquiring the latest orbit
`information of the GPS satellite in response to a request from a GPS receiver, a position information acquisition
`means for acquiring position information from the GPS receiver, and a positioning operation control means for
`controlling each positioning operation in a normal sensitivity positioning mode in which the GPS receiver is operated
`only when necessary and a high sensitivity positioning mode in which the GPS receiver is always operated by
`controlling the power of the GPS receiver; and a positioning control unit having a positioning mode switching means
`for switching between the normal sensitivity positioning mode and the high sensitivity positioning mode of the GPS
`receiver, and an orbit information supply means for supplying the orbit information acquisition means with orbit
`information obtained via a network using the communication control unit.
`[Claim 2]
`The position information communication terminal according to claim 1, provided with a man-machine interface
`control unit that outputs information corresponding to the operation of the terminal user, wherein the positioning
`control unit switches between the normal sensitivity positioning mode and the high sensitivity positioning mode of
`the GPS receiver based on the request of the terminal user acquired via the man-machine interface control unit.
`[Claim 3]
`The position information communication terminal according to claim 1, wherein the communication control unit
`receives positioning control information transmitted from the outside, and the positioning control unit switches
`between the normal sensitivity positioning mode and the high sensitivity positioning mode of the GPS receiver based
`on the positioning control information.
`[Claim 4]
`The position information communication terminal according to claim 1, provided with a satellite signal level detecting
`unit for detecting the level of the GPS signal received by the GPS receiver, wherein the positioning control unit
`switches between the normal sensitivity positioning mode and the high sensitivity positioning mode of the GPS
`receiver based on the signal level information acquired from the satellite signal level detecting unit.
`[Claim 5]
`The position information communication terminal according to claim 1, provided with a battery that supplies
`operating power, and a battery control unit that notifies the positioning control unit of a remaining battery amount
`warning when the remaining amount value of the battery is lower than a preset threshold value, wherein the
`positioning control unit switches between the normal sensitivity positioning mode and the high sensitivity positioning
`mode of the GPS receiver based on the remaining battery amount warning information.
`[Claim 6]
`The position information communication terminal according to claim 1, provided with a battery that supplies
`operating power, a battery control unit that notifies the positioning control unit of a remaining battery amount warning
`when the remaining amount value of the battery is lower than a preset threshold value, and a man-machine interface
`control unit for notifying the terminal user of the remaining battery amount warning; wherein the positioning control
`unit switches between the normal sensitivity positioning mode and the high sensitivity positioning mode of the GPS
`receiver based on the remaining battery amount warning.
`[Claim 7]
`The GPS positioning system according to claim 1, consisting of a position management server that searches the
`position of the terminal, provided with a position information communication terminal, a communication control unit
`having mobile communication means that connects to the terminal via a mobile communication network, a positioning
`mode control unit that transmits and receives positioning control information to and from the terminal via the
`communication control unit, and a GPS satellite information management unit that collects and manages GPS satellite
`information and sends the latest GPS satellite orbit information to the terminal via the mobile communication
`network;
`wherein the positioning control unit of the terminal switches between the normal sensitivity positioning mode and the
`high sensitivity positioning mode of the GPS receiver based on the positioning control information from the position
`management server.
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`[Claim 8]
`The GPS positioning system according to claim 7, wherein the positioning mode control unit sets positioning mode
`information that specifies the positioning operation of the GPS receiver of the terminal to the normal sensitivity
`positioning mode or the high sensitivity positioning mode, as positioning control information, based on an instruction
`from a position searcher, and the communication control unit of the position management server transmits positioning
`control information in which the positioning mode information is set to the terminal via a mobile communication
`network.
`[Claim 9]
`The GPS positioning system according to claim 7, wherein the terminal is provided with a satellite signal level
`detecting unit that detects a level of the GPS signal received by the GPS receiver, the positioning control unit sets the
`signal level information to positioning control information, the communication control unit of the terminal transmits
`positioning control information in which the signal level information is set to the position management server via a
`mobile communication network, the positioning mode control unit of the position management server, based on the
`signal level information, sets positioning mode information for specifying the positioning operation of the GPS
`receiver of the terminal as the normal sensitivity positioning mode or the high sensitivity positioning mode to the
`positioning control information, and the communication control unit of the position management server transmits
`positioning control information in which the positioning mode information is set to the terminal via a mobile
`communication network.
`[Claim 10]
`The GPS positioning system according to claim 7, wherein the terminal is provided with a battery that supplies
`operating power, and a battery control unit that notifies the positioning control unit of a remaining battery amount
`warning when the remaining amount value of the battery is lower than a preset threshold value; wherein the
`positioning control unit sets the remaining battery amount warning information to positioning control information,
`the communication control unit of the terminal transmits the positioning control information in which the remaining
`battery amount warning information is set to the position management server via the mobile communication network,
`the positioning mode control unit of the position management server, based on the remaining battery amount warning
`information, sets the positioning mode information for specifying the positioning operation of the GPS receiver of
`the terminal as the normal sensitivity positioning mode or the high sensitivity positioning mode to the positioning
`control information, and the communication control unit of the position management server transmits positioning
`control information in which the positioning mode information is set to the terminal via a mobile communication
`network.
`[Claim 11]
`The GPS positioning system according to claim 7, wherein the terminal is provided with a battery that supplies
`operating power, and a battery control unit that notifies the positioning control unit of a remaining battery amount
`warning when the remaining amount value of the battery is lower than a preset threshold value; wherein the
`positioning mode control unit of the position management server, based on the remaining battery amount warning
`information, notifies the position searcher of the battery remaining warning, sets the positioning mode information
`specifying the positioning operation of the GPS receiver of the terminal in the normal sensitivity positioning mode or
`the high sensitivity positioning mode to the positioning control information, and the communication control unit of
`the position management server transmits positioning control information in which the positioning mode information
`is set to the terminal via a mobile communication network.
`[Claim 12]
`The GPS positioning system according to any one of claims 7 to 11, provided with a communication line status control
`unit in the position information communication terminal or the position management server that switches the
`communication line connecting the position information communication terminal with the position management
`server via the mobile communication network between a mode that is always connected and a mode that is connected
`for each position search based on a request from a position searcher.
`[Detailed Description of the Invention]
`[0001]
`[Technical Field of the Invention]
`The present invention relates to a position information communication terminal capable of position measurement
`using a GPS receiver, and a GPS positioning system.
`[0002]
`[Prior Art]
`In Japanese Unexamined Patent Publication No. 10-31061 a technology is disclosed that shortens the time from
`power-on to the first position detection by inputting the latest navigation message of the GPS satellite from the
`outside to the
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`GPS receiver. However, it is difficult to track and capture the GPS satellite signal with a level lower than the
`signal level that can be captured using this technique.
`[0003]
`Therefore, there is a highly sensitive positioning operation that always operates the GPS receiver as a GPS receiving
`technique capable of detecting the position even in an environment where the satellite signal level is lower after once
`capturing the GPS satellite. However, it is necessary to keep the GPS receiver itself running, and when applied to
`devices with limited battery capacity such as portable terminals, it is necessary to flexibly control the operation mode
`of the GPS receiver from the outside and selectively use the highly sensitive positioning operation and the normal
`positioning operation.
`[0004]
`[Problems to be Solved by the Invention]
`The present invention has been developed in light of the above reasons; the purpose thereof is to provide a position
`information communication terminal and a GPS positioning system wherein it is possible to flexibly switch between
`the normal sensitivity positioning mode in which the GPS receiver operates only when necessary and the high
`sensitivity positioning mode in which it operates constantly.
`[0005]
`[Means for Solving the Problems]
`The invention according to claim 1 is provided with a GPS receiver that receives GPS satellite signals from GPS
`satellites and performs positioning operations;
`a communication control unit having a mobile communication means;
`a GPS control unit having an orbit information acquisition means for acquiring the latest orbit information of the GPS
`satellite in response to a request from a GPS receiver, a position information acquisition means for acquiring position
`information from the GPS receiver, and a positioning operation control means for controlling each positioning
`operation in a normal sensitivity positioning mode in which the GPS receiver is operated only when necessary and a
`high sensitivity positioning mode in which the GPS receiver is always operated by controlling the power of the GPS
`receiver; and
`a positioning control unit having a positioning mode switching means for switching between the normal sensitivity
`positioning mode and the high sensitivity positioning mode of the GPS receiver, and an orbit information supply
`means for supplying the orbit information acquisition means with orbit information obtained via a network using the
`communication control unit.
`[0006]
`The invention of claim 2 according to claim 1, provided with a man-machine interface control unit that outputs
`information corresponding to the operation of the terminal user, wherein the positioning control unit switches between
`the normal sensitivity positioning mode and the high sensitivity positioning mode of the GPS receiver based on the
`request of the terminal user acquired via the man-machine interface control unit.
`[0007]
`The invention of claim 3 according to claim 1, wherein the communication control unit receives positioning control
`information transmitted from the outside, and the positioning control unit switches between the normal sensitivity
`positioning mode and the high sensitivity positioning mode of the GPS receiver based on the positioning control
`information.
`[0008]
`The invention of claim 4 according to claim 1, provided with a satellite signal level detecting unit for detecting the
`level of the GPS signal received by the GPS receiver, wherein the positioning control unit switches between the
`normal sensitivity positioning mode and the high sensitivity positioning mode of the GPS receiver based on the signal
`level information acquired from the satellite signal level detecting unit.
`[0009]
`The invention of claim 5 according to claim 1, provided with a battery that supplies operating power, and a battery
`control unit that notifies the positioning control unit of a remaining battery amount warning when the remaining
`amount value of the battery is lower than a preset threshold value, wherein the positioning control unit switches
`between the normal sensitivity positioning mode and the high sensitivity positioning mode of the GPS receiver based
`on the remaining battery amount warning information.
`[0010]
`The invention of claim 6 according to claim 1, provided with a battery that supplies operating power, a battery control
`unit that notifies the positioning control unit of a remaining battery amount warning when the remaining amount value
`of the battery is lower than a preset threshold value, and a man-machine interface control unit for notifying the
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`terminal user of the remaining battery amount warning; wherein the positioning control unit switches between the
`normal sensitivity positioning mode and the high sensitivity positioning mode of the GPS receiver based on the
`remaining battery amount warning.
`[0011]
`The invention of claim 7 according to claim 1, consisting of a position management server that searches the position
`of the terminal, provided with a position information communication terminal, a communication control unit having
`mobile communication means connected to the terminal via a mobile communication network, a positioning mode
`control unit that transmits and receives positioning control information to and from the terminal via the
`communication control unit, and a GPS satellite information management unit that collects and manages GPS satellite
`information and sends the latest GPS satellite orbit information to the terminal via the mobile communication
`network;
`wherein the positioning control unit of the terminal switches between the normal sensitivity positioning mode and the
`high sensitivity positioning mode of the GPS receiver based on the positioning control information from the position
`management server.
`[0012]
`The invention of claim 8 according to claim 7, wherein the positioning mode control unit sets positioning mode
`information that specifies the positioning operation of the GPS receiver of the terminal to the normal sensitivity
`positioning mode or the high sensitivity positioning mode, as positioning control information, based on an instruction
`from a position searcher, and the communication control unit of the position management server transmits positioning
`control information in which the positioning mode information is set to the terminal via a mobile communication
`network.
`[0013]
`The invention of claim 9 according to claim 7, wherein the terminal is provided with a satellite signal level detecting
`unit that detects a level of the GPS signal received by the GPS receiver, the positioning control unit sets the signal
`level information to positioning control information, the communication control unit of the terminal transmits
`positioning control information in which the signal level information is set to the position management server via a
`mobile communication network, the positioning mode control unit of the position management server, based on the
`signal level information, sets positioning mode information for specifying the positioning operation of the GPS
`receiver of the terminal as the normal sensitivity positioning mode or the high sensitivity positioning mode to the
`positioning control information, and the communication control unit of the position management server transmits
`positioning control information in which the positioning mode information is set to the terminal via a mobile
`communication network.
`[0014]
`The invention of claim 10 according to claim 7, wherein the terminal is provided with a battery that supplies operating
`power, and a battery control unit that notifies the positioning control unit of a remaining battery amount warning when
`the remaining amount value of the battery is lower than a preset threshold value; wherein the positioning control unit
`sets the remaining battery amount warning information to positioning control information, the communication control
`unit of the terminal transmits the positioning control information in which the remaining battery amount warning
`information is set to the position management server via the mobile communication network, the positioning mode
`control unit of the position management server, based on the remaining battery amount warning information, sets the
`positioning mode information for specifying the positioning operation of the GPS receiver of the terminal as the
`normal sensitivity positioning mode or the high sensitivity positioning mode to the positioning control information,
`and the communication control unit of the position management server transmits positioning control information in
`which the positioning mode information is set to the terminal via a mobile communication network.
`[0015]
`The invention of claim 11 according to claim 7, wherein the terminal is provided with a battery that supplies operating
`power, and a battery control unit that notifies the positioning control unit of a remaining battery amount warning when
`the remaining amount value of the battery is lower than a preset threshold value; wherein the positioning mode control
`unit of the position management server, based on the remaining battery amount warning information, notifies the
`position searcher of the battery remaining warning, sets the positioning mode information specifying the positioning
`operation of the GPS receiver of the terminal in the normal sensitivity positioning mode or the high sensitivity
`positioning mode to the positioning control information, and the communication control unit of the position
`management server transmits positioning control information in which the positioning mode information is set to the
`terminal via a mobile communication network.
`[0016]
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`(6)
`The invention of claim 12 according to any one of claims 7 to 11, provided with a communication line status control
`unit in the position information communication terminal or the position management server that switches the
`communication line connecting the position information communication terminal with the position management
`server via the mobile communication network between a mode that is always connected and a mode that is connected
`for each position search based on a request from a position searcher.
`[0017]
`[Form for Embodying the Invention]
`Hereinafter, embodiments of the present invention will be described with reference to the drawings.
`[0018]
`(Embodiment 1)
`As shown in FIG. 2, the GPS positioning system according to the present embodiment has a position information
`communication terminal 1, and a position management / positioning server 2 connected with the position information
`communication terminal 1 by a mobile communication network. The position information communication terminal 1
`makes a position response to the position request from the terminal user A and shows the position of the position
`information communication terminal 1 to the terminal user A. The position management / positioning server 2
`responds to the position search request of the position information communication terminal 1 from the position
`searcher B with a position response, and indicates the position of the position information communication terminal 1
`to the position searcher B.
`[0019]
`In this embodiment, the position information communication terminal 1 will be described. The position information
`communication terminal 1 is, as shown in FIG. 1, composed of a GPS receiver 10 which receives GPS satellite signals
`from GPS satellites and performs positioning operations; a communication control unit 11 having a mobile
`communication means; an orbit information acquisition means for acquiring the latest orbit information of the GPS
`satellite; a position information acquisition means for acquiring position information from the GPS receiver 10; a
`positioning operation control means wherein, by controlling the power supply of the GPS receiver 10, each
`positioning operation is controlled in the normal sensitivity positioning mode in which the GPS receiver 10 is operated
`only when necessary and the high sensitivity positioning mode in which the GPS receiver 10 is always operated; a
`positioning control unit 13 having a positioning mode switching means for switching between the normal sensitivity
`positioning mode and the high sensitivity positioning mode of the GPS receiver 10, and an orbital information supply
`means for supplying the orbit information of the GPS satellite acquired from the GPS satellite information obtained
`via the mobile communication network (network) by using the communication control unit 11 to the orbit information
`acquisition means of the GPS control unit 12; a man-machine interface control unit 14 which is an interface means
`with the terminal user A; a satellite signal level detection unit 15 for detecting the level of the GPS satellite signal
`received by the GPS receiver 10 via the GPS control unit 12; a battery control unit 16 that notifies the positioning
`control unit 13 of a remaining battery amount warning when the remaining amount value of a battery (not shown)
`that supplies operating power falls below a preset threshold value; and a communication line status control unit 17
`that switches the communication line between the mode that is always connected and the mode that is connected
`every time a position is searched based on the line control signal from the positioning control unit 13, via the mobile
`communication network between the position information communication terminal 1 and the position management /
`positioning server 2.
`[0020]
`The operation of the position information communication terminal 1 will be described below. The position
`information communication terminal 1 waits in a state in which the power of the GPS receiver 10 is cut off; in order
`to obtain terminal user A’s own position, a position request is sent to the positioning control unit 13 by pressing the
`button provided on the man-machine interface control unit 14. The positioning control unit 13 that has received the
`position request turns on the power of the GPS receiver 10 via the GPS control unit 12 and the GPS receiver 10 starts
`the position detection process.
`[0021]
`The GPS receiver 10 determines whether or not the orbit information of the GPS satellite stored in the GPS receiver
`10 is the latest in order to shorten the time until the position is first detected after the power is turned on. If it
`determines that the orbit information is not the latest, it requests the latest orbit information from the GPS control unit
`12.
`[0022]
`Upon receiving the request for the orbit information, the GPS control unit 12 requests the positioning control unit 13
`to acquire the GPS satellite information. The positioning control unit 13 uses the communication control unit 11 to
`acquire GPS satellite information via the mobile communication network and sends it to the GPS control unit 12; the
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`GPS control unit 12 then obtains orbit information from the GPS satellite information, and sends it to receiver 10.
`The GPS receiver 10 refers to the latest orbit information to perform the position detection processing.
`[0023]
`Then, when the GPS receiver 10 performs the position detection processing and succeeds in positioning, the position
`information is acquired by the GPS control unit 12, and then the position is shown to the terminal user A on the display
`unit provided in the man-machine interface control unit 14 via the positioning control unit 13.
`[0024]
`After successful positioning, the positioning control unit 13 requests the GPS control unit 12 to turn off the power of
`the GPS receiver 10, and the GPS receiver 10 is turned off again. In this way, a series of positioning operations in
`which the power is turned on by the position request from the power-off state and the positioning is successful and
`then the power is turned off again is set to the normal sensitivity positioning mode.
`[0025]
`Here, when the GPS receiver 10 succeeds in the positioning once by the internal positioning calculation technology,
`the GPS receiver 10 can continue to capture and position even if the signal level from the GPS satellite drops to a
`certain value. Therefore, once the positioning is successful, if the GPS receiver 10 continues to operate without being
`cut off, at the next position request, even if the signal level from the GPS satellite is lower than that at the time of the
`first positioning, the positioning can be successful. In this way, the series of positioning operations for constantly
`operating the GPS receiver 10 is referred to as the “high sensitivity positioning mode.”
`[0026]
`When the terminal user A selects either the normal sensitivity positioning mode or the high sensitivity positioning
`mode to request the position, it is set by operating the man-machine interface control unit 14, and positioning is
`performed in the normal sensitivity positioning mode or the high sensitivity positioning mode based on the setting
`information.
`[0027]
`When the position of the position information communication terminal 1 is in an environment where it is easy to
`receive the GPS signal from the GPS satellite, the signal level received by the GPS receiver 10 becomes high.
`Therefore, the man-machine interface control unit 14 is operated in advance to set a constant threshold value K1 in
`the positioning control unit 13 for each signal level of a plurality of GPS satellites. The positioning control unit 13
`compares the level of the GPS satellite signal detected by the satellite signal level detection unit 15 via the GPS
`receiver 10 and the GPS control unit 12 with the threshold value K1, and if the detection level is below the threshold
`K1, the positioning control unit 13 automatically makes a transition to the high sensitivity positioning mode. Further,
`a threshold value K2 different from the threshold value K1 is set in the positioning control unit 13, and when the
`detection level exceeds the threshold value K2, the positioning control unit 13 automatically makes a transition to the
`normal sensitivity positioning mode.
`[0028]
`In addition, the battery control unit 16 inside the position information communication terminal 1 constantly monitors
`the remaining battery level; if the remaining battery level becomes low and it becomes difficult to operate the GPS
`receiver 10, the positioning control unit 13 is notified of the remaining battery amount warning. When the positioning
`control unit 13 receives this remaining battery amount warning, it issues a remaining battery amount warning
`notification to the terminal user A via the man-machine interface control unit 14. Upon receiving this warning, the
`terminal user A operates the man-machine interface control unit 14 as described above to select from the normal
`sensitivity positioning mode, the high sensitivity positioning mode, or cutting off the power of the position
`information communication terminal 1.
`[0029]
`Further, the man-machine interface control unit 14 is operated in advance to set the threshold value of the remaining
`battery level in the battery control unit 16; by registering the positioning mode selection process in the positioning
`control unit 13 when the remaining battery amount monitored by the battery control unit 16 is below the threshold
`value and a remaining battery amount warning is issued, when the battery control unit 16 notifies the positioning
`control unit 13 of the remaining battery amount warning, it becomes possible to automatically shift the positioning
`mode to the normal sensitivity positioning mode.
`[0030]
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`JP 2004-37116 (P2004-37116A)
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`(Embodiment 2)
`First, as shown in FIG. 3, the position management / positioning server 2 of the present embodiment is composed of
`a communication control unit 21 having a mobile communication means connected to the position information
`communication terminal 1 via a mobile communication network; a positioning mode control unit 22 that transmits
`and receives a positioning control message (positioning control information) to and from the position information
`communication terminal 1 via the communication control unit 21; a GPS satellite information management unit 23
`that coll