JP5284929B2 - Mobile communication terminal - Google Patents

Description

  The present invention relates to a portable communication terminal having a position positioning function by GPS (Global Positioning System).

  Conventionally, a GPS positioning service has been provided to acquire current location information of a mobile communication terminal. In this service, the mobile communication terminal needs to hold time information (system time) for synchronizing with a GPS satellite signal.

  By the way, when the mobile communication terminal communicating with the base station synchronizes with the base station, the mobile communication terminal can acquire time information held by the base station with higher accuracy than the clock of the mobile communication terminal itself. The mobile communication terminal can update the system time using the acquired time information and synchronize with the GPS satellite signal. Further, for example, a method of estimating the time held by a GPS satellite and updating this time information as needed has been proposed (see, for example, Patent Document 1).

Japanese Patent Laying-Open No. 2005-086320

  However, during positioning processing by GPS, the system time for synchronizing with GPS satellite signals is required to change smoothly, and there is no need for corners or jumps. That is, when the system time is updated, depending on the update timing, appropriate positioning processing is not executed, and the mobile communication terminal may increase the positioning time, fail in positioning, or decrease positioning accuracy. There was a case.

  In addition, the system time of the mobile communication terminal is not limited to the GPS positioning application, and may be referred to in other applications.

  An object of this invention is to provide the portable communication terminal which can update system time, without affecting a GPS positioning function.

  A mobile communication terminal according to the present invention is updated by a receiving unit that receives time data from a base station, an updating unit that updates a system time based on the time data received by the receiving unit, and the updating unit. A storage unit that holds the system time before the update, and a positioning unit that performs GPS positioning processing using the updated system time updated by the update unit or the system time before update held by the storage unit; A positioning monitoring unit that monitors the progress of the GPS positioning process and detects a timing when the system time can be changed and cannot be changed based on a predetermined condition set in advance, and the system by the positioning monitoring unit When it is detected that the time cannot be changed, the positioning unit uses the system time before update held by the storage unit If the sensed and capable of changing the system time timing, the positioning unit and a switching unit for switching to use the system time after the update.

  Further, it is preferable that the switching unit discards the system time before the update held by the storage unit when the positioning unit uses the updated system time.

  In addition, the positioning monitoring unit changes the system time in at least one of a section in which GPS satellite acquisition auxiliary information is acquired in the GPS positioning processing, GPS satellite signal synchronization, and distance measurement from the GPS satellite are performed. It is preferable to make the timing impossible.

  In addition, when the positioning unit repeatedly performs the GPS positioning process, the positioning monitoring unit further determines a section between one positioning process and the next positioning process and a timing at which the system time cannot be changed. It is preferable to detect.

  The mobile communication terminal according to the present invention further includes a time monitoring unit that monitors the time data received by the receiving unit and detects a difference between the time indicated by the time data and the system time, Preferably, the unit updates the system time when the time monitoring unit detects a difference between the time and the system time.

  According to the present invention, the system time can be updated without affecting the GPS positioning function.

1 is an external perspective view of a mobile phone according to an embodiment of the present invention. It is a block diagram which shows the function of the mobile telephone which concerns on embodiment of this invention. It is a sequence diagram which shows the positioning process in Assisted mode which concerns on embodiment of this invention. It is a sequence diagram which shows the positioning process in Based mode which concerns on embodiment of this invention. It is a sequence diagram which shows the positioning process in Stand alone mode which concerns on embodiment of this invention. It is a figure which shows an example of the switching timing of the system time which concerns on embodiment of this invention. It is a flowchart which shows the system time monitoring process which concerns on embodiment of this invention. It is a flowchart which shows the GPS positioning monitoring process which concerns on embodiment of this invention. It is a flowchart which shows the system time update process which concerns on embodiment of this invention.

  Hereinafter, an example of an embodiment of the present invention will be described. In the present embodiment, a mobile phone 1 will be described as an example of a mobile communication terminal.

FIG. 1 is an external perspective view of a mobile phone 1 (mobile communication terminal) according to the present embodiment.
The mobile phone 1 includes an operation unit side body 2 and a display unit side body 3. The operation unit side body 2 includes an operation unit 11 on the front surface unit 10 and a microphone 12 to which a voice uttered by a user of the mobile phone 1 during a call or when using a voice recognition application is input. The The operation unit 11 includes a function setting operation button 13 for activating various functions such as various setting functions, a telephone book function, and a mail function, and an input operation button 14 for inputting numbers of telephone numbers, mail characters, and the like. , And a determination operation button 15 for performing determination and scrolling in various operations.

  The display unit side body 3 includes a display unit 21 for displaying various types of information on the surface unit 20 and a receiver 22 for outputting the voice of the other party of the call.

  Further, the upper end portion of the operation unit side body 2 and the lower end portion of the display unit side body 3 are connected via a hinge mechanism 4. In addition, the mobile phone 1 relatively rotates the operation unit side body 2 and the display unit side body 3 which are connected via the hinge mechanism 4, so that the operation unit side body 2 and the display unit side body 3 are rotated. The body 3 can be in an open state (open state), or the operation unit side body 2 and the display unit side body 3 can be folded (folded state).

FIG. 2 is a block diagram showing functions of the mobile phone 1 according to the present embodiment.
The mobile phone 1 includes an operation unit 11, a display unit 21, a control unit 30, a communication unit 40 (receiving unit), a main antenna 41, a GPS communication unit 50, a GPS antenna 51, and a voice control unit 60. And a storage unit 70.

  The control unit 30 controls the entire mobile phone 1, and performs predetermined control on the display unit 21, the communication unit 40, the GPS communication unit 50, the voice control unit 60, and the like, for example. In addition, the control unit 30 receives input from the operation unit 11 or the like and executes various processes. Then, the control unit 30 controls the storage unit 70 to read various programs and data, and write data when executing processing.

  Furthermore, the control unit 30 includes a time monitoring unit 31, an updating unit 32, a positioning unit 33, a positioning monitoring unit 34, and a switching unit 35. And control part 30 will output the acquired position information based on the predetermined processing accompanied by communication with a base station, if the positioning request of the present position is received from the user of cellular phone 1. In addition, the function of each part with which the control part 30 is provided is mentioned later.

  The communication unit 40 communicates with an external device (base station) in a predetermined frequency band (for example, 2 GHz band or 800 MHz band). Then, the communication unit 40 demodulates the signal received from the main antenna 41, supplies the processed signal to the control unit 30, modulates the signal supplied from the control unit 30, and outputs the signal from the main antenna 41. Send to external device.

  In particular, in this embodiment, the communication unit 40 is connected to a positioning server from a base station via a network in addition to transmission / reception of signals related to voice calls, mails, etc., and satellite search auxiliary information (GPS satellite acquisition auxiliary information) And obtain positioning results. Although details will be described later, the positioning method executed by the control unit 30 is different and the contents of transmitted / received data are also different depending on the satellite acquisition status.

  In the present embodiment, the communication unit 40 receives highly accurate system time (time data) held by the base station in order to adjust the system time of the mobile phone 1.

  The GPS communication unit 50 demodulates a radio signal of a predetermined frequency band from a GPS satellite received by the GPS antenna 51 and supplies the processed signal to the control unit 30. The functions of the GPS communication unit 50 and the GPS antenna 51 may be performed by the communication unit 40 and the main antenna 41, respectively.

  The sound control unit 60 performs predetermined sound processing on the signal supplied from the communication unit 40 under the control of the control unit 30, and outputs the processed signal to the receiver 22. The receiver 22 outputs the signal supplied from the audio control unit 60 to the outside. This signal may be output from a speaker (not shown) instead of the receiver 22 or together with the receiver 22.

  In addition, the voice control unit 60 processes the signal input from the microphone 12 according to the control of the control unit 30, and outputs the processed signal to the communication unit 40. The communication unit 40 performs predetermined processing on the signal supplied from the voice control unit 60 and outputs the processed signal from the main antenna 41.

  The storage unit 70 includes, for example, a working memory and is used for arithmetic processing by the control unit 30. In the present embodiment, a program for executing processing described later, various databases, and the like are stored. Note that the storage unit 70 may also serve as a removable external memory.

  Here, the types of GPS positioning in the mobile phone 1 will be described. There are an Assisted mode, a Based mode, and a Stand alone mode for positioning.

  In the Assisted mode, the mobile phone 1 receives satellite search auxiliary information (AA (Acquisition Assistance) data) from the positioning server, and searches for GPS satellites. The search result is returned to the positioning server, and position calculation is performed by the positioning server. The mobile phone 1 receives the position calculation result and outputs it as a positioning result.

  In the Based mode, the mobile phone 1 receives satellite information (Ephemeris data and Almanac data) from the base station. The mobile phone 1 searches for satellites after creating AA data based on the received satellite information. Furthermore, the mobile phone 1 performs its own position calculation without transmitting the search result to the positioning server. Therefore, in the Based mode, positioning cannot be performed when the mobile phone 1 cannot capture the satellite.

  In the stand alone mode, the mobile phone 1 does not communicate with the base station for positioning. That is, the mobile phone 1 decodes the GPS satellite signal and acquires Ephemeris data and Almanac data by itself.

  In the Based mode and the Stand alone mode, the mobile phone 1 uses the Ephemeris data, Almanac data, and the positioning result acquired in the previous positioning for the next positioning.

  Next, each step of the GPS positioning process will be described. The GPS positioning process includes the steps of “AA data acquisition (creation)”, “GPS satellite search”, “satellite signal synchronization”, “pseudo distance measurement”, “position calculation”, and “positioning information storage”.

  The AA data acquisition (creation) step is different between the Assisted mode and the Based mode or the Stand alone mode.

  First, in the Assisted mode, the mobile phone 1 acquires AA data created by the base station by communication. The AA data is obtained by calculating GPS satellites that can be captured around the base station and their positions from Ephemeris data broadcast by the GPS satellites and the system time (time data) of the base station. Therefore, if there is a difference between the system time of the base station used to create the AA data and the system time of the mobile phone 1, there is a concern that the positioning accuracy may be lowered. That is, if the system time of the mobile phone 1 is updated while AA data is being received, the AA data is the old system time, but the mobile phone 1 holds the new system time. Changes are not allowed.

  Next, in the case of the Based mode, the mobile phone 1 obtains Ephemeris data and Almanac data through communication, and creates AA data. Also in this case, if the system time is deviated between the creation of AA data and the start of the GPS satellite search, the accuracy of the AA data deteriorates, so that the system time cannot be changed. In the stand alone mode, Ephemeris data and Almanac data are obtained by decoding GPS satellite signals.

  In the GPS satellite search step, the mobile phone 1 determines a visible satellite based on the AA data, the current time (system time), and the current position, and searches for a GPS satellite signal. Once the search is started, there is no need to refer to the system time if a predetermined period (1 ms) can be counted. Therefore, in this step, the system time can be changed.

  In the satellite signal synchronization step, the mobile phone 1 acquires a navigation message in synchronization with the signal captured in the GPS satellite search step. The mobile phone 1 needs to be synchronized with signals from a plurality of GPS satellites and continue to be synchronized until the next pseudo-range measurement step is executed, but time information is used for this signal synchronization. If the system time is changed, synchronization may be lost. Therefore, in this step, the system time cannot be changed.

  In the pseudo distance measuring step, the mobile phone 1 measures the pseudo distance between the mobile phone 1 and each GPS satellite. The pseudo distance is obtained from the difference between the time when the signal is transmitted from the GPS satellite and the time when the mobile phone 1 receives it. At this time, if the system time of the mobile phone 1 is changed, accurate distance measurement cannot be performed, which causes a positioning failure or a decrease in positioning accuracy. Therefore, in this step, the system time cannot be changed.

  In the position calculation step, the mobile phone 1 (positioning server in the case of the Assisted mode) calculates the current location of the mobile phone 1 based on the pseudo distance with each GPS satellite. Since time information is not required for the calculation, the system time can be changed in this step.

  In the based mode or the stand alone mode, in the positioning information saving step, the mobile phone 1 uses the data and positioning results used in the previous positioning operation for the next positioning in order to shorten the positioning time and improve the positioning accuracy. Save as you can. At this time, there is no problem in the positioning operation even if the system time is changed, but there is a case where the old time stamp data cannot be used correctly at the next positioning. Therefore, it is desirable not to update the system time in this step.

  From the above, it is the AA data acquisition (creation) step, the satellite synchronization step, and the pseudorange measurement step that prohibit the update of the system time during the execution of the GPS positioning process. The timing at which the system time cannot be changed for each positioning mode is shown in FIGS.

FIG. 3 is a sequence diagram showing a positioning process in the Assisted mode according to the present embodiment.
The mobile phone 1 measures the approximate position (base station positioning 1) based on the position information of the base station, then acquires AA data (AA data request, AA data transmission), GPS satellite search, satellite signal synchronization Each step of pseudo distance measurement is executed. Subsequently, after the base station positioning 2, the mobile phone 1 requests the base station for a position calculation result, and receives the position calculation result calculated by the positioning server from the base station. Among these steps, the AA data acquisition, satellite signal synchronization, and pseudorange measurement steps are affected by the system time change and cannot be changed.

FIG. 4 is a sequence diagram showing a positioning process in the Based mode according to the present embodiment.
After acquiring Ephemeris data and Almanac data after base station positioning, the mobile phone 1 repeatedly executes a series of steps of AA data creation, GPS satellite search, satellite signal synchronization, pseudorange measurement, position calculation, and positioning information storage. . Among these steps, the AA data creation, satellite signal synchronization, and pseudorange measurement steps are affected by the system time change and cannot be changed.

FIG. 5 is a sequence diagram showing a positioning process in the stand alone mode according to the present embodiment.
The cellular phone 1 repeatedly executes a series of steps of AA data creation, GPS satellite search, satellite signal synchronization, pseudorange measurement, position calculation, and positioning information storage. Among these steps, the AA data creation, satellite signal synchronization, and pseudorange measurement steps are affected by the system time change and cannot be changed.

Returning to FIG. 2, the function of each unit of the control unit 30 according to the present embodiment will be described in detail.
The time monitoring unit 31 monitors the system time (time data) of the base station received by the communication unit 40 and detects a difference between the system time and the system time held by the mobile phone 1.

The updating unit 32 updates the system time of the mobile phone 1 based on the system time of the base station when the time monitoring unit 31 detects a difference between the system time of the base station and the system time of the mobile phone 1. .
In the present embodiment, as the system time of the mobile phone 1 is updated by the update unit 32, the system time before being updated by the update unit 32 is held in the storage unit 70 as a pseudo system time. .

  The positioning unit 33 performs GPS positioning processing using the updated system time updated by the updating unit 32 or the pre-update system time held by the storage unit 70.

  The positioning monitoring unit 34 monitors the progress of the GPS positioning process, that is, which step is being executed, and the system time can be changed and cannot be changed based on a predetermined condition set in advance. To detect the timing. Specifically, the positioning monitoring unit 34 detects that the system time cannot be changed during the steps of AA data acquisition (creation), satellite signal synchronization, and pseudorange measurement.

  Further, when the positioning unit 33 repeatedly performs the GPS positioning process, the positioning monitoring unit 34 detects a section between one positioning process and the next positioning process as a timing at which the system time cannot be changed. To do.

When the positioning monitoring unit 34 detects that the system time cannot be changed, the switching unit 35 can change the system time using the system time before the update held in the storage unit 70 by the positioning unit 33. If the timing is detected, the positioning unit 33 switches to use the updated system time.
In addition, when the positioning unit 33 uses the updated system time, the switching unit 35 discards the system time before the update held by the storage unit 70.

  FIG. 6 is a diagram showing an example of the system time switching timing according to the present embodiment. In this example, the positioning unit 33 performs the GPS positioning process in the Based mode or the Stand alone mode.

  After the first GPS positioning process is completed and the positioning information is saved, when a change in the system time is detected by the time monitoring unit 31, in the case of FIG. 6A, the system time cannot be changed. Not detected and switched to new system time. In this case, the old system time stamp is assigned in the positioning information storing step of the first GPS positioning process. Then, in the AA data acquisition (creation) step of the second GPS positioning process, the old system time of the previous positioning information and the new system time that is the current time information are referred to, and the consistency cannot be obtained.

  Therefore, the positioning monitoring unit 34 detects that the system time cannot be updated during the period from the positioning information storage to the start of the next positioning process, and prohibits switching of the system time. Specifically, as shown in FIG. 6B, after a change in the system time is detected, the pseudo system time (old system time) is used, and the AA data acquisition (creation) step is performed in the next positioning process. When finished, it is switched to the new system time.

FIG. 7 is a flowchart showing system time monitoring processing by the time monitoring unit 31 according to the present embodiment.
In step S <b> 1, the time monitoring unit 31 acquires the system time of the base station by the communication unit 40.

  In step S2, the time monitoring unit 31 determines whether or not the system time of the mobile phone 1 is different from the system time of the base station. If this determination is YES, control unit 30 moves the process to step S3, and if the determination is NO, the control unit 30 moves the process to step S4.

  In step S3, the time monitoring unit 31 notifies the control unit 30 that the system time has changed as a trigger for changing the system time.

  In step S4, the time monitoring unit 31 determines whether or not an end request for this processing has been received. If this determination is YES, the control unit 30 ends the process, and if the determination is NO, the control unit 30 returns the process to step S1.

FIG. 8 is a flowchart showing the GPS positioning monitoring process by the positioning monitoring unit 34 according to the present embodiment.
In step S <b> 11, the positioning monitoring unit 34 determines the type of function / application being activated that requests position positioning.

  In step S12, the positioning monitoring unit 34 determines the change permission timing of the system time according to the function / application type determined in step S11. Specifically, the positioning monitoring unit 34 determines the timing when the system time can be changed and cannot be changed in units of the above steps in the GPS positioning process. This change permission timing may be determined based on condition data for each function / application stored in the storage unit 70 in advance.

  In step S <b> 13, the positioning monitoring unit 34 monitors the status of the GPS positioning process, and determines the progress status (step in progress).

  In step S14, the positioning monitoring unit 34 determines whether the step in progress determined in step S13 is the changeable timing determined in step S12. When this determination is YES, control unit 30 moves the process to step S15, and when the determination is NO, returns control to step S13.

  In step S15, the positioning monitoring unit 34 notifies the controller 30 of permission to change the system time as a trigger for switching the system time.

  In step S <b> 16, the positioning monitoring unit 34 determines whether a termination request for this process has been accepted. If this determination is YES, the control unit 30 ends the process, and if the determination is NO, the control unit 30 returns the process to step S13.

  FIG. 9 is a flowchart showing system time update processing by the control unit 30 (particularly, the update unit 32 and the switching unit 35) according to the present embodiment. This processing is executed in response to activation of a function / application that involves GPS positioning processing.

  In step S <b> 21, the control unit 30 activates the system time monitoring process (FIG. 7) by the time monitoring unit 31.

  In step S22, the control unit 30 (update unit 32) determines whether or not a change in the system time has been notified by the system time monitoring process (FIG. 7). If this determination is YES, control unit 30 moves the process to step S23, and if the determination is NO, repeats step S22.

  In step S23, the control unit 30 activates the GPS positioning monitoring process (FIG. 8) by the positioning monitoring unit 34.

  In step S24, the control unit 30 (switching unit 35) creates a pseudo system time in the storage unit 70, and switches the positioning unit 33 to use this pseudo system time.

  In step S25, the control unit 30 (update unit 32) updates the regular system time held by the mobile phone 1 with the system time of the base station.

  In step S26, the control unit 30 (switching unit 35) determines whether or not the change permission of the regular system time has been notified by the GPS positioning monitoring process (FIG. 8). If this determination is YES, control unit 30 moves the process to step S27, and if the determination is NO, repeats step S26.

  In step S27, since the control unit 30 (switching unit 35) can change the system time, the positioning unit changes from the pseudo system time (old system time) to the regular system time after change (new system time). The system time used by 33 is switched.

  In step S28, the control unit 30 notifies the positioning monitoring unit 34 of an end request and stops the GPS positioning monitoring process (FIG. 8).

  In step S <b> 29, the control unit 30 (switching unit 35) discards the unnecessary pseudo system time from the storage unit 70.

  In step S <b> 30, the control unit 30 determines whether a termination request for this processing has been received from a function / application or the like. If this determination is YES, control unit 30 moves the process to step S31. If the determination is NO, control unit 30 returns the process to step S22.

  In step S31, the control unit 30 notifies the time monitoring unit 31 of an end request, and stops the system time monitoring process (FIG. 7).

  As described above, according to the present embodiment, even if the system time received from the base station is shifted during the positioning operation by GPS, the pseudo system time is used, so that the regular system time is Positioning can be continued without being affected by the change. Therefore, it can be expected to improve the accuracy of the positioning result and shorten the positioning time.

  Further, according to the present embodiment, by creating the pseudo system time, the system time received from the base station can be immediately updated as the system time of the mobile phone 1 even during the GPS positioning operation. Therefore, the function / application that refers to the system time can continue the normal operation.

  Furthermore, according to the present embodiment, the reference destination is switched from the pseudo system time to the regular system time at a possible timing by monitoring the state of the positioning operation. Therefore, time stamps of various positioning data created after the positioning operation can be used as correct time information. As a result, it is possible to appropriately use the positioning data in the time position positioning, so that it is expected to improve the accuracy of the position positioning result and shorten the positioning time.

  In addition, according to the present embodiment, it is possible to set the timing for switching the system time (system time changeable and non-changeable timing) according to the use of the function / application that requires positioning. Stable positioning is possible according to the situation.

  As mentioned above, although preferred embodiment was described, this invention can be implemented with a various form, without being limited to embodiment mentioned above. In addition, the effects described in the above-described embodiments are merely a list of the most preferable effects resulting from the present invention, and the effects according to the present invention are not limited to those described above.

  In the above-described embodiment, the mobile phone 1 is described as a mobile communication terminal. However, the mobile communication terminal is not limited to this, and the present invention is not limited to PHS (registered trademark; Personal Handyphone System), PDA (Personal Digital Assistant). ), And can be applied to various portable communication terminals such as game machines, navigation devices, and personal computers.

  Furthermore, in the above-described embodiment, the mobile phone 1 is a type that can be folded by the hinge mechanism 4, but is not limited thereto. The mobile phone 1 is not such a foldable type, but a slide type in which one case is slid in one direction from a state where the operation unit side case 2 and the display unit side case 3 are overlapped, A rotary type (turn type) in which one casing is rotated around the axis line along the overlapping direction of the operation unit side body 2 and the display unit side body 3 or the operation unit side body 2 and the display. The part side housing 3 may be a type (straight type) that is arranged in one housing and does not have a connecting portion. The mobile phone 1 may be a so-called biaxial hinge type that can be opened and closed and rotated.

1 Mobile phone (mobile communication terminal)
DESCRIPTION OF SYMBOLS 11 Operation part 21 Display part 30 Control part 31 Time monitoring part 32 Update part 33 Positioning part 34 Positioning monitoring part 35 Switching part 40 Communication part (receiving part)
41 Main antenna 50 GPS communication unit 51 GPS antenna 60 Voice control unit 70 Storage unit

Claims (5)

A receiving unit for receiving time data from the base station;
An update unit that updates a system time based on the time data received by the reception unit;
A storage unit for holding a system time before being updated by the updating unit;
A positioning unit that performs GPS positioning processing using the updated system time updated by the updating unit, or the system time before updating held by the storage unit;
A positioning monitoring unit that monitors the progress of the GPS positioning process and detects a timing at which the system time can be changed and cannot be changed based on a predetermined condition set in advance;
When the positioning monitoring unit detects that the system time cannot be changed, the positioning unit uses the pre-update system time held by the storage unit, and the system time can be changed. And a switching unit that switches so that the positioning unit uses the updated system time when detected.   2. The mobile communication terminal according to claim 1, wherein when the positioning unit uses the updated system time, the switching unit discards the system time before the update held by the storage unit.   The positioning monitoring unit cannot change the system time in at least one of the sections in which GPS satellite acquisition auxiliary information is acquired in the GPS positioning process, the GPS satellite signal is synchronized, and the distance from the GPS satellite is measured. The mobile communication terminal according to claim 1, wherein the mobile communication terminal is set to a proper timing.   When the positioning unit repeatedly performs the GPS positioning process, the positioning monitoring unit detects a section between one positioning process and the next positioning process as a timing at which the system time cannot be changed. The portable communication terminal according to claim 3. Further comprising a time monitoring unit that monitors the time data received by the receiving unit and detects a difference between the time indicated by the time data and the system time;
The mobile communication terminal according to any one of claims 1 to 4, wherein the update unit updates the system time when a difference between the time and the system time is detected by the time monitoring unit. .

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