JP2005337791A - Terminal device, method and program for controlling terminal device, and computer-readable recording medium with control program of terminal device recorded thereon - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a terminal device and the like capable outputting latitude information and longitude information of high accuracy in two-dimensional positioning. <P>SOLUTION: In this terminal device 30 having a positioning means for measuring a present position by receiving a position-related signal S1 or the like from a positional information satellite 12a or the like, the terminal device 30 includes a last positioning position storing means for storing the positional information on the last positioning including the last altitude information indicating the altitude of the position of the last positioning, an estimated moving distance information creating means for creating the estimated moving distance information indicating an estimated moving distance with the lapse of time on the basis of the lapse of time from the last positioning, a present estimated error information creating means for creating the present estimated error information indicating the present estimated error on the basis of the last estimated error information and the estimated moving distance information, and an use allowable range determining means or the like for determining whether the present estimated error is within the allowable range or not. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a terminal device, a terminal device control method, a terminal device control program, and a computer-readable recording medium on which the terminal device control program is recorded.

Conventionally, a GPS receiver that receives a position-related signal from a GPS (Global Positioning System) satellite, for example, a position information satellite and measures a current position, receives a position-related signal from four or more GPS satellites, 3D positioning is performed to generate information, longitude information and altitude information.
If position information signals cannot be received from four or more GPS satellites, two-dimensional positioning for generating latitude information and longitude information is performed by receiving position information signals from three GPS satellites.
In order to perform this two-dimensional positioning, the GPS receiver needs to acquire altitude information of the current position in advance.

On the other hand, a technique using altitude information with high accuracy among altitude information included in position information previously measured by a GPS receiver and altitude information input from the outside has been proposed (for example, Patent Document 1, FIG. 4 etc.).
JP 2002-341010 A

  However, as described above, even if altitude information included in the position information previously measured by the GPS receiver and altitude information input from the outside is used with high accuracy, the altitude indicated in the altitude information is used. There may be a large error between the input altitude (hereinafter referred to as the input altitude) and the actual altitude. When the two-dimensional positioning is performed in a state where the error between the input altitude and the actual altitude is large, not only the error in the altitude direction increases, but also the error in the horizontal direction (latitude / longitude direction) increases. There is a problem of outputting large latitude information and longitude information.

  Therefore, the present invention provides a terminal device capable of outputting highly accurate latitude information and longitude information in two-dimensional positioning, a terminal device control method, a terminal device control program, and a computer reading recording a terminal device control program. An object is to provide a possible recording medium.

  According to the first aspect of the present invention, there is provided a terminal device having positioning means for measuring a current position by receiving a position related signal from a position information satellite, wherein the terminal device has a receiving sensitivity capable of positioning. Positioning-possible receiving sensitivity satellite number determining means for determining the number of the position information satellites capable of receiving the position related signal, and the previous positioning position information including the previous altitude information indicating the altitude of the previous positioning position. Positioning position information storage means, initial position information input means for using the previous positioning position information as initial position information for positioning the current position, and previous positioning error information indicating a positioning error of the previous positioning position are stored. Estimated travel distance information generation for generating estimated travel distance information indicating the estimated travel distance in the elapsed time based on the previous positioning error information storage means and the elapsed time from the previous positioning A current estimated error information generating means for generating current estimated error information indicating a current estimated error based on the previous positioning error information and the estimated moving distance information; and a current estimated error indicating an allowable range of the current estimated error Current estimation error tolerance range information storage means for storing tolerance range information; and use allowable range inside / outside judgment means for judging whether or not the current estimation error is within the tolerance range, wherein the current estimation error is the tolerance When it is determined that the current position is within the range, the present invention is achieved by a terminal device that outputs current position information indicating the current position.

  According to the configuration of the first invention, when the terminal device determines that the current estimation error is within the allowable range, the terminal device outputs current position information indicating the current position.

  Here, the current estimated error information is information indicating a range in which the current position of the terminal device is estimated to exist. The fact that the current estimation error indicated in the current estimation error information is large means that the range in which the true current position can be estimated is large.

The large current estimation error means that not only the latitude direction and the longitude direction but also the altitude direction estimation error is large.
Here, if the current estimation error is larger than a certain range and the estimation error in the altitude direction is also large, outputting a positioning result of two-dimensional positioning will not only output a positioning result having a large altitude direction error. In addition, a positioning result having a large error in the horizontal direction (latitude and longitude direction) is output.

  In this regard, since the configuration of the present invention outputs the current position information indicating the current position only when the current estimation error is determined to be within the allowable range, the latitude information with high accuracy is obtained in the two-dimensional positioning. And longitude information can be output.

  According to a second invention, in the configuration of the first invention, the previous position information is a three-dimensional positioning in which the positioning means performs three-dimensional positioning by receiving the position-related signals from four or more position information satellites. It is the positioning information at the time.

According to the configuration of the second invention, since the previous positioning position information is the positioning position information at the time of the three-dimensional positioning, the previous positioning position is more than the altitude information included in the positioning position information at the time of two-dimensional positioning. The previous altitude information included in the information is highly accurate.
For this reason, by using the previous altitude information with high accuracy, latitude information and longitude information with higher accuracy can be output in the two-dimensional positioning.

  According to a third aspect of the present invention, in the configuration of the first aspect or the second aspect, when the positioning unit can receive the position-related signals from four or more position information satellites, three-dimensional positioning is performed. It is characterized by performing.

In general, a positioning result of three-dimensional positioning performed by receiving the position-related signals from four or more positioning information satellites is more reliable than a positioning result of two-dimensional positioning.
As described above, in the two-dimensional positioning, the terminal device outputs current position information indicating the current position only when it is determined that the current estimated error distance is equal to or less than the previous altitude effective threshold. .
For this reason, according to the structure of 3rd invention, the said terminal device can always output a highly accurate positioning result.

  According to the fourth aspect of the present invention, the terminal device having positioning means for receiving a position-related signal from a position information satellite and positioning the current position receives the position-related signal having a receiving sensitivity capable of positioning. A step of determining the number of positionable reception sensitivity satellites that determines the number of position information satellites that can be performed, and the terminal device currently uses the previous positioning position information including the previous altitude information indicating the altitude of the previous positioning position as the initial position information. A positioning step for positioning a position, a previous positioning error information acquisition step in which the terminal device acquires previous positioning error information indicating a positioning error of the previous positioning position, and the terminal device based on an elapsed time from the previous positioning time. An estimated moving distance information generating step for generating estimated moving distance information indicating the estimated moving distance in the elapsed time, and the terminal device includes the previous positioning error information and the previous A current estimated error information generating step for generating current estimated error information indicating a current estimated error based on the estimated moving distance information; and the terminal device determines whether the current estimated error is within an allowable range of the current estimated error. A current estimated error allowable range inside / outside determining step to determine, and if the terminal device determines that the current estimated error is within the allowable range, current position information indicating the current position acquired in the positioning step is And a current position information output step for outputting. This is achieved by a control method of a terminal device.

  According to the configuration of the fourth invention, as in the configuration of the first invention, it is possible to output highly accurate latitude information and longitude information in two-dimensional positioning.

  According to a fifth aspect of the present invention, in the configuration of the fourth aspect of the present invention, the previous position information is a three-dimensional positioning in which the positioning means performs three-dimensional positioning by receiving the position-related signals from four or more position information satellites. It is time position information.

  According to the configuration of the fifth aspect of the invention, as in the configuration of the second aspect of the invention, by using the previous altitude information with high accuracy included in the position information at the time of the three-dimensional positioning, High latitude information and longitude information can be output.

  According to a sixth invention, in the configuration of the fourth invention or the configuration of the fifth invention, when the positioning means can receive the position-related signals from four or more position information satellites, three-dimensional positioning is performed. It is characterized by performing.

  According to the configuration of the sixth invention, like the configuration of the third invention, the terminal device can always output a positioning result with high accuracy.

  According to the seventh aspect of the present invention, there is provided a terminal device having positioning means for receiving a position related signal from a position information satellite and positioning a current position in a computer. A positioning-capable receiving sensitivity satellite number determining step for determining the number of the position information satellites capable of receiving a signal, and the terminal device including the previous positioning position information including the previous altitude information indicating the altitude of the previous positioning position as an initial position; A positioning step for positioning the current position as information, a previous positioning error information acquisition step in which the terminal device acquires previous positioning error information indicating a positioning error at the previous positioning position, and a lapse of time since the previous positioning by the terminal device An estimated movement distance information generating step for generating estimated movement distance information indicating an estimated movement distance in the elapsed time based on time; and A current estimated error generating step for generating current estimated error information indicating a current estimated error based on the position error information and the estimated moving distance information; and the terminal device, wherein the current estimated error is within an allowable range of the current estimated error. A current estimated error allowable range inside / outside determining step for determining whether or not the terminal device indicates the current position acquired in the positioning step when the terminal device determines that the current estimated error is within the allowable range The present invention is achieved by a control program for a terminal device, characterized in that a current position information output step for outputting current position information is executed.

  According to an eighth aspect of the present invention, there is provided a terminal device having positioning means for receiving a position-related signal from a position information satellite and positioning a current position in a computer. A positioning-capable receiving sensitivity satellite number determining step for determining the number of the position information satellites capable of receiving a signal, and the terminal device including the previous positioning position information including the previous altitude information indicating the altitude of the previous positioning position as an initial position; A positioning step for positioning the current position as information, a previous positioning error information acquisition step in which the terminal device acquires previous positioning error information indicating a positioning error of the previous positioning position, and a time elapsed since the previous positioning. An estimated movement distance information generating step for generating estimated movement distance information indicating an estimated movement distance in the elapsed time based on time; and A current estimated error generating step for generating current estimated error information indicating a current estimated error based on the position error information and the estimated moving distance information; and the terminal device, wherein the current estimated error is within an allowable range of the current estimated error. A current estimated error allowable range inside / outside determining step for determining whether or not the terminal device indicates the current position acquired in the positioning step when the terminal device determines that the current estimated error is within the allowable range The present invention is achieved by a computer-readable recording medium on which a control program for a terminal device is recorded, wherein a current position information output step for outputting current position information is executed.

  According to a ninth aspect of the present invention, there is provided a terminal device having positioning means for measuring a current position by receiving a position-related signal from a position information satellite, wherein the terminal device has a receiving sensitivity capable of positioning. Positioning-possible receiving sensitivity satellite number determining means for determining the number of the position information satellites capable of receiving the position related signal, and the previous positioning position information including the previous altitude information indicating the altitude of the previous positioning position. Positioning position information storage means, initial position information input means for using the previous positioning position information as initial position information for positioning the current position, and previous positioning error information indicating a positioning error of the previous positioning position are stored. Previous positioning error information storage means, current positioning position information acquisition means for acquiring current positioning position information indicating the current positioning position, and current positioning error information indicating the current positioning error of the current position Current positioning error information acquisition means to acquire, current position error information indicating current position estimation error information based on the previous positioning position information, the previous positioning error information, the current positioning position information, and the current positioning error information An estimation error information generating means; a current estimation error allowable range information storage means for storing current estimation error allowable range information indicating an allowable range of the current estimation error; and determining whether the current estimation error is within the allowable range. A current position estimation error allowable range inside / outside determination means, and when determining that the current position estimation error is within the allowable range, outputs a current position information indicating the current position. Achieved by:

According to the configuration of the ninth invention, unlike the configuration of the first invention, the current position estimation error is based on the previous positioning position information, the previous positioning error information, the current positioning position information, and the current positioning error information. Is generated, and it is determined whether or not the current time estimation error is within the allowable range.
That is, the configuration of the ninth invention is different from the configuration of the first invention having the estimated movement distance information generating means, the previous positioning position information and the previous positioning error information stored in the terminal device, and the The current positioning position information and the current positioning error information held without being output by the terminal device are used.
The estimated moving distance information generated by the estimated moving distance information generating means in the configuration of the first invention assumes, for example, the moving speed of the terminal device, and the assumed moving speed and the elapsed time from the previous positioning. However, depending on the actual moving speed of the terminal device, the estimated moving distance may differ greatly from the actual moving distance.
In this regard, according to the configuration of the ninth invention, the current position estimation error information is generated based on the previous positioning position information and the like that are actually measured and held, and the current positioning position information and the like. It is not affected by the actual moving speed of the terminal device or the elapsed time.
For this reason, it is possible to output highly accurate latitude information and longitude information in two-dimensional positioning without being affected by the actual moving speed of the terminal device or the elapsed time.

  According to a tenth aspect of the invention, in the configuration of the ninth aspect, the previous position information is a three-dimensional positioning in which the positioning means performs three-dimensional positioning by receiving the position-related signals from four or more position information satellites. It is time position information.

  According to the configuration of the tenth invention, by using the previous altitude information that is included in the position information at the time of the three-dimensional positioning, the accuracy is high in the two-dimensional positioning as in the ninth invention. Latitude information and longitude information can be output.

  According to the eleventh aspect of the present invention, the terminal device having positioning means for receiving a position-related signal from a position information satellite and positioning the current position receives the position-related signal having a receiving sensitivity capable of positioning. A step of determining the number of positionable reception sensitivity satellites that determines the number of position information satellites that can be performed, and the terminal device currently uses the previous positioning position information including the previous altitude information indicating the altitude of the previous positioning position as the initial position information. A positioning step of positioning a position, a previous positioning error information acquisition step in which the terminal apparatus acquires previous positioning error information indicating a positioning error of the previous positioning position, and a current positioning position in which the terminal apparatus indicates the current positioning position. A current positioning position information acquisition step for acquiring information; and a current positioning error in which the terminal device acquires current positioning error information indicating a current positioning error of the current positioning position. A current information generation step, wherein the terminal device generates current estimation error information indicating a current estimation error based on the previous positioning position information, the previous positioning error information, the current positioning position information, and the current positioning error information. An estimation error information generation step; a determination step for determining whether the current estimation error is within the allowable range; or a determination step for determining whether the current estimation error is within the allowable range; and a determination that the terminal device has the current estimation error within the allowable range. A position information output step of outputting current position information indicating the current position acquired in the positioning step. This is achieved by a control method of a terminal device.

  According to the configuration of the eleventh invention, as in the configuration of the ninth invention, latitude information with high accuracy is obtained in two-dimensional positioning without being affected by the actual moving speed of the terminal device or the elapsed time. And longitude information can be output.

  In a twelfth aspect based on the configuration according to the eleventh aspect, the previous positioning position information is a three-dimensional positioning in which the positioning means receives the position-related signals from four or more position information satellites and performs three-dimensional positioning. It is the position information at the time of positioning.

In general, the positioning result of the three-dimensional positioning has higher reliability than the positioning result of the two-dimensional positioning.
As described above, in the two-dimensional positioning, the terminal device outputs current position information indicating the current position only when it is determined that the current estimated error distance is equal to or less than the altitude effective threshold.
For this reason, according to the structure of 12th invention, the said terminal device can always output a positioning result with high precision.

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.
The embodiments described below are preferred specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention is particularly limited in the following description. Unless otherwise stated, the present invention is not limited to these embodiments.

(First embodiment)
FIG. 1 is a schematic diagram showing a terminal 30 and the like according to an embodiment of the present invention.
As shown in FIG. 1, for example, a terminal 30 that is a terminal device receives, for example, signals S1, S2, S3, and S4 that are position related signals from GPS satellites 12a, 12b, 12c, and 12d that are position information satellites. It has a positioning device 33 that is a positioning means for receiving and positioning the current position. The terminal 30 is a GPS receiver, for example.
Unlike the present embodiment, the number of GPS satellites 12a and the like may be four or more.
The reception environment such as the signal S1 defined by the position of the terminal 30 held by the user A affects how many signals from the GPS satellites 12a can be used for positioning. For example, the terminal 30 may receive a signal S1 or the like from four or more GPS satellites 12a to 12d to perform three-dimensional positioning, or may receive a signal S1 or the like from three GPS satellites 12a to 12c and perform two-dimensional positioning. In some cases, positioning is performed.
The terminal 30 may be a mobile phone equipped with a GPS receiver, a PHS (Personal Handy-phone System), a PDA (Personal Digital Assistance _), or the like.

(Main hardware configuration of terminal 30)
FIG. 2 is a schematic diagram showing the main hardware configuration of the terminal 30.
As shown in FIG. 2, the terminal 30 includes, for example, a computer, and the computer includes a bus 32. The bus 32 includes a CPU (Central Processing Unit) 34, a storage device 36, an input device 38, and the like. It is connected. The storage device 36 is, for example, a RAM (Random Access Memory) or a ROM (Read Only Memory).
That is, the bus 32 has a function of connecting all devices, and is an internal bus having an address and a data path.
The CPU 34 is a control unit that controls a ROM or the like as a storage unit connected to the bus 32 in addition to processing a predetermined program.

The bus 32 is connected to a signal receiving device 40 for receiving a signal S1 and the like from the GPS satellite 12a and the like.
The bus 32 is connected to a measuring device 42 that measures satellite information such as the GPS satellite 12a and the propagation time of the signal S1. The satellite information measured by the measuring device 42 and information indicating the propagation time such as the signal S1 are stored in the storage device 36 described above. Based on the satellite information stored in the storage device 36 and the information indicating the propagation time such as the signal S1, the CPU 34 measures the current position of the terminal 30.
That is, the signal receiving device 40, the measuring device 42, the storage device 36, and the CPU 34 are positioning means for receiving the signal S1 or the like from the GPS satellite 12a or the like and positioning the current position.

  The bus 32 is connected with a display device 46 for displaying various information and a clock 48 for measuring the passage of time.

(Main software configuration of terminal 30)
FIG. 3 is a schematic diagram showing the main software configuration of the terminal 30.
FIG. 4 is a diagram illustrating the previous positioning position P1 and the like.
As shown in FIG. 3, the terminal 30 includes a signal receiving unit 102 corresponding to the signal receiving device 40 in FIG. 2, a time measuring unit 104 corresponding to the measuring device 42 in FIG. 2, and a display unit corresponding to the display device 46 in FIG. 106, and a timer 108 corresponding to the timepiece 48 of FIG.
The terminal 30 also includes a terminal control unit 100 that controls each unit.

  As illustrated in FIG. 3, the terminal 30 includes a first storage unit 110 that stores various programs, a second storage unit 140 that stores various types of information in advance, and a third storage that stores information acquired or generated by the terminal 30. Part 150.

The terminal 30 stores a positioning possible satellite number determination program 112 in the first storage unit 110. The number-of-positionable-satellite-number determination program 112 determines how many GPS satellites 12a, etc., of the GPS satellites 12a, etc. in FIG. This is information for judgment. That is, the positioning-possible satellite number determination program 112 and the terminal control unit 100 are an example of positioning-receivable sensitivity satellite number confirmation means.
The terminal control unit 100 determines how many GPS satellites 12a or the like can receive the positioning sensitivity signal S1 or the like based on the positioning-possible satellite number determination program 112, and determines four or more positions. If it is determined that the signal S1 or the like having a positioning sensitivity that can be measured can be received from the information satellite 12a or the like, three-dimensional positioning is executed.
On the other hand, when it is determined that the terminal control unit 100 can receive signals S1 and the like having a receiving sensitivity that can be measured from the three position information satellites 12a and the like, the terminal control unit 100 performs two-dimensional positioning.

As illustrated in FIG. 3, the terminal 30 stores the previous positioning position information 156 in the third storage unit 150. The previous positioning position information 156 is information indicating the positioning position of the terminal 30 at the previous positioning, for example, information indicating the previous positioning position P1 of FIG.
The previous positioning position information 156 includes previous latitude / longitude information 156a indicating the latitude and longitude of the positioning position at the previous positioning, and previous altitude information 156b indicating the altitude of the positioning position at the previous positioning.
The previous positioning position information 156 is an example of the previous positioning position information. The previous altitude information 156b is an example of the previous altitude information.
That is, the third storage unit 150 is an example of a previous positioning position information storage unit.

  The previous positioning position information 156 described above is information indicating a positioning position at the time of three-dimensional positioning in which the positioning device 33 in FIG. 1 receives the signal S1 from four or more GPS satellites 12a and the like and performs three-dimensional positioning. is there. Therefore, the previous altitude information 156b is highly accurate information generated by actual positioning.

As shown in FIG. 3, the terminal 30 has an initial position information input program 114. The initial position information input program 114 is information for the terminal control unit 100 to use the previous positioning position information 156 as initial position information for positioning the current position. That is, the initial position information input program 114 and the terminal control unit 100 are examples of initial position information input means.
The terminal control unit 30 executes the above-described two-dimensional positioning or three-dimensional positioning using the previous positioning position information 156 as initial position information.

As illustrated in FIG. 3, the terminal 30 stores the previous positioning error information 160 in the third storage unit 150. The previous positioning error information 160 is information indicating the positioning error of the positioning position at the previous positioning. That is, the third storage unit 150 is an example of a previous positioning error information storage unit.
The above positioning error is a distance that varies depending on the positioning environment or the reception environment. For example, when the terminal 30 receives a signal S1 or the like from the GPS satellite 12a or the like outdoors with good reception sensitivity, for example, it is 10 meters (m). On the other hand, when the terminal 30 receives the signal S1 from the GPS satellite 12a or the like indoors with poor reception sensitivity, for example, it is 100 meters (m).

  As illustrated in FIG. 3, the terminal 30 stores elapsed time information 162 in the third storage unit 150. The elapsed time information 162 is information indicating the passage of time since the previous positioning. The elapsed time information 162 is generated by the time measuring unit 108 and stored in the third storage unit 150 by the terminal control unit 100.

As illustrated in FIG. 3, the terminal 30 stores an estimated travel distance information generation program 116 in the first storage unit 110. The estimated travel distance information generation program 116 causes the terminal control unit 100 to generate estimated travel distance information indicating the estimated travel distance in the elapsed time based on the elapsed time from the previous positioning indicated in the elapsed time information 162 described above. It is information to do. That is, the estimated movement distance information generation program 116 and the terminal control unit 100 are an example of estimated movement distance information generation means.
The terminal control unit 100 stores the generated estimated movement distance information 164 in the third storage unit 150.

As shown in FIG. 3, the terminal 30 has a current estimated error information generation program 118.
The current estimated error information generation program 118 is configured so that the terminal control unit 100 indicates the current estimated error information indicating the current estimated error based on the previous positioning estimated error information 160 and the estimated moving distance information 164 stored in the third storage unit 150. It is information for generating. That is, the current estimated error information generation program 118 and the terminal control unit 100 are examples of current estimated error information generation means. Here, the current estimation error means a range in which it is estimated that a true current position can exist.
The terminal control unit 100 stores the generated current estimated error information 166 in the third storage unit 150.

  As illustrated in FIG. 3, the terminal 30 stores the previous altitude effective threshold information 142 in the second storage unit 140. The previous altitude effective threshold information 142 is an example of current estimated error allowable range information. That is, the second storage unit 140 is an example of a currently estimated error allowable range information storage unit.

The terminal 30 also has a current estimated error threshold judgment program 120. The current estimated error threshold judgment program 120 is based on the previous estimated effective threshold information 142 stored in the second storage unit 140 in advance by the terminal control unit 100 and the current estimated error information 166 stored in the third storage unit 150. Thus, this is information for determining whether or not the current estimated error distance d3 in FIG. 4 is less than or equal to the previous altitude effective threshold. The terminal 30 determines whether or not the current estimated error distance d3 in FIG. 4 is within an allowable range based on whether or not the current estimated error distance d3 in FIG. 4 is less than or equal to the previous altitude effective threshold. That is, the current estimated error threshold determination program 120 and the terminal control unit 100 are examples of use allowable range inside / outside determination means.
Here, the previous altitude effective threshold information 142 is information for determining whether or not to output a positioning result acquired using the previous altitude information 156b as altitude information for two-dimensional positioning of the current position. is there.
The previous altitude effective threshold shown in the previous altitude effective threshold information 142 is a threshold that defines the allowable range of the current estimated error distance d3 in FIG.

As described above, the current estimated error information 166 is information indicating a range in which it is estimated that the current position of the terminal 30 may exist. The fact that the current estimation error distance d3 in FIG. 4 shown in the current estimation error information 166 is large means that the range in which the true current position of the terminal 30 can exist is large.
The fact that the range in which the true current position can exist is large means that the range of the position in the altitude direction in which the true current position can exist is also large.
If the current estimated error distance d3 is larger than a certain threshold value, the range of the altitude direction position is also large, so outputting a positioning result of two-dimensional positioning not only outputs a positioning result with a large altitude direction error, Latitude information and longitude information with a large error in the horizontal direction (latitude and longitude direction) are output.
In order to prevent the terminal 30 from outputting latitude information and longitude information with large errors as described later, the user 30 in FIG. The altitude effective threshold is defined so that the positioning result error falls within the range, and the positioning result is output only when the current estimated error distance d3 is smaller than the altitude effective threshold.

  As shown in FIG. 3, the terminal 30 has a positioning result output program 122. The positioning result output program 122 displays the current position indicating the current position when the terminal control unit 100 determines that the current estimated error distance d3 in FIG. 4 is less than or equal to the altitude effective threshold based on the current estimated error threshold determination program 120. This is information for outputting information.

The positioning error distance d1 and the like described above will be specifically described with reference to FIG.
The previous positioning error distance d1 of the previous positioning position P1 shown in FIG. 4 is an example of the positioning error of the previous positioning position, and is, for example, 10 meters (m).
The estimated travel distance d2 in FIG. 4 is an example of the estimated travel distance indicated in the estimated travel distance information 164. The estimated movement distance information 164 is generated by the terminal control unit 100 and the estimated movement distance information generation program 116. That is, the terminal control unit 100 is, for example, 40 meters per second (m / s) that is the provisional moving speed of the terminal 30 (hereinafter referred to as assumed moving speed) defined in the estimated moving distance information generating program 116. Based on, for example, 3,600 seconds (s) indicated in the elapsed time information 162 described above, the estimated travel distance information 164 indicating the estimated travel distance d2 of 144,000 meters (m) is generated (FIG. 3). reference).
The current estimated error distance d3 in FIG. 4 is an example of the current estimated error indicated in the current estimated error information 166 (see FIG. 3). The current estimated error information 166 is generated by the terminal control unit 100 and the current estimated error information generation program 118. That is, the terminal control unit 100, based on the current estimated error information generation program 118, 10 meters (m) that is the previous positioning error distance d1 indicated in the previous positioning error information 160 and the estimation indicated in the estimated movement distance information 164. Based on the moving distance d2 of 144,000 meters (m), current estimated error information 166 indicating the current estimated error distance d3 of 144,010 meters (m) is generated.
As described above, the altitude effective threshold shown in the previous altitude effective threshold information 142 in FIG. 3 is such that the error in the positioning result is within the range where the user A in FIG. 1 can practically use the positioning result. For example, it is 10 kilometers (km) to 20 kilometers (km).
As described above, the terminal 30 is indicated in the previous positioning position information 156 if the current estimated error distance d3 is 144,010 meters (m) and the altitude effective threshold is larger than, for example, 20 kilometers (km). The result of two-dimensional positioning using the previous altitude information 156b is not output.
On the other hand, when the current estimated error distance d3 is an altitude effective threshold value, for example, 20 km (km) or less, two-dimensional positioning is performed using the previous altitude information 156b indicated in the previous positioning position information 156. The result of performing is output and displayed on the display device 46 of FIG. 2, for example.

As described above, since the terminal 30 performs two-dimensional positioning using the previous altitude information 156b having high accuracy included in the previous positioning position information 156 that is position information at the time of three-dimensional positioning, the latitude with high accuracy is obtained. Only information and longitude information can be output.
The terminal 30 performs three-dimensional positioning when the signal S1 and the like can be received from four or more GSP satellites 12a and the like. In general, the positioning result of the three-dimensional positioning has higher reliability than the positioning result of the two-dimensional positioning.
Therefore, the terminal 30 can always output only a highly accurate positioning result.

(Regarding the operation example of the terminal 30 of the first embodiment)
Although the terminal 30 is configured as described above, an example of its operation will be described below.
5 and 6 are schematic flowcharts showing an operation example of the terminal 30. FIG.

When the terminal 30 receives an instruction for positioning the current position from the former in FIG. 1, the terminal 30 determines whether or not the number of GPS satellites 12a and the like that can receive a positioning sensitivity signal S1 and the like is four or more. (Step ST1). That is, step ST1 is an example of a step for determining the number of positioning-sensitive reception sensitivity satellites.
If there are four or more GPS satellites 12a or the like that can receive signals S1 and the like having a positioning sensitivity, the terminal 30 starts three-dimensional positioning (step ST11 in FIG. 5) and acquires the positioning results (steps). (ST12) The positioning result is output by the display unit 106 in FIG. 3 (step ST9 in FIG. 6).
As described above, the terminal 30 performs three-dimensional positioning when the signal S1 and the like can be received from four or more GPS satellites 12a and the like. As the initial position of positioning, the previous positioning position shown in the previous positioning position information 156 in FIG. 3 is used.

On the other hand, if there are three GPS satellites 12a or the like that can receive signals S1 and the like with positioning sensitivity, the terminal 30 performs two-dimensional positioning (step ST2 in FIG. 5) and acquires the positioning results (step ST3). ). As the initial position of positioning, the previous positioning position shown in the previous positioning position information 156 in FIG. 3 is used. Here, previous altitude information 156b indicating the altitude of the previous positioning position included in the previous positioning position information 156 is also used for positioning. That is, step ST2 and step ST3 are an example of a positioning step for positioning the current position using the previous positioning position information 156 including the previous altitude information indicating the altitude of the previous positioning position as the initial position information.
Here, since the previous positioning position information 145 is position information at the time of three-dimensional positioning in which the terminal 30 has received the signal S1 or the like from four or more GPS satellites 12a and the like and performed three-dimensional positioning, the previous altitude information 156b is information with high accuracy. The result of two-dimensional positioning using the previous altitude information 156b with high accuracy can also be expected to have high accuracy.
As described above, in step ST3, the terminal 30 acquires a positioning result of two-dimensional positioning. Whether or not to output the positioning result is determined by the following steps.

First, the terminal 30 acquires the previous positioning error information 160 (see FIG. 3) indicating the estimated error distance d1 of the previous positioning position P1 shown in FIG. 4 (step ST4). That is, step ST
4 is an example of the previous positioning error information acquisition step.
Subsequently, the terminal 30 generates elapsed time information 162 (see FIG. 3) indicating the elapsed time from the previous positioning (step ST5).
Subsequently, based on the elapsed time information 162, the terminal 30 generates estimated travel distance information 164 (see FIG. 3) indicating the estimated travel distance d2 at the elapsed time indicated in the elapsed time information 162 (step ST6 in FIG. 6). ). That is, step ST6 is an example of an estimated movement distance information generation step.

Subsequently, the terminal 30 generates current estimation error information 166 indicating the current estimation error based on the previous positioning estimation error information 160 and the estimated movement distance information 164 (step ST7 in FIG. 6). That is, step ST7 is an example of a current estimated error information generation step.
Specifically, the terminal 30 generates a current estimated error distance d3 that is a distance obtained by adding d2 to d1 based on the estimated error distance d1 and the estimated moving distance d2 in FIG. The current estimated error information 166 shown is stored in the first storage unit 150 of FIG.

  Subsequently, the terminal 30 determines that the estimated error distance d3 in FIG. 4 is the previous altitude effective threshold based on the previous altitude effective threshold information 142 stored in advance in the second storage unit 140 in FIG. 3 and the current estimated error information 166 described above. It is determined whether or not it is equal to or lower than the previous altitude effective threshold indicated by information 142 (step ST8). That is, the terminal 30 determines whether or not the current estimated error distance d3 is within the allowable range based on whether or not the estimated error distance d3 is equal to or less than the previous altitude effective threshold value indicated in the previous altitude effective threshold information 142. That is, step ST8 is an example of a step for judging whether the current estimated error is within or outside the allowable range.

For example, it is assumed that the previous estimated error distance d1 (see FIG. 4) indicated in the previous positioning estimated error information 160 is 10 meters (m). If the elapsed time from the previous positioning is 3,600 seconds (s) and the assumed moving speed of the terminal 30 is 40 meters per second (40 m / s), the estimated movement indicated by the estimated movement distance information 156 The distance d2 is 144,000 meters (m). In this case, the current estimated error distance d3 (see FIG. 4) is 144,010 meters (m).
Then, if the previous altitude effective threshold value indicated in the previous altitude effective threshold information 142 is, for example, 20 kilometers (km), the terminal 30 determines that the estimated error distance d3 in FIG. It is determined that it is not less than the effective threshold value, and the positioning result of the two-dimensional positioning is not output (step ST81).

On the other hand, in the above example, if the elapsed time from the previous positioning is 300 seconds (s), the estimated movement distance d2 indicated in the estimated movement distance information 156 is 12,000 meters (m). The current estimated error distance d3 (see FIG. 4) is 12,010 meters (m).
In this case, the terminal 30 determines that the current estimated error distance d3 in FIG. 4 is the previous altitude effective threshold indicated in the previous altitude effective threshold information 142, for example, 20 km (km) or less, and step ST3 in FIG. The positioning result of the two-dimensional positioning acquired in step 3 is output by the display unit 106 of FIG. This step ST9 is an example of a current position information output step.

As described above, the terminal 30 outputs the current position information indicating the current position only when it is determined that the current estimated error distance d3, which is an example of the current estimated error, is equal to or less than the altitude effective threshold value. In positioning, highly accurate latitude information and longitude information can be output.
Further, as described above, the terminal 30 performs three-dimensional positioning when the signal S1 and the like can be received from four or more GPS satellites 12a and the like. In general, the positioning result of the three-dimensional positioning has higher reliability than the positioning result of the two-dimensional positioning.
For this reason, the terminal 30 can always output only a highly accurate positioning result.

(Second Embodiment)
Next, the terminal 31 (FIG. 1) as 2nd Embodiment is demonstrated. Since the configuration of the terminal 31 in the second embodiment is similar to the configuration of the terminal 30 in the first embodiment, common portions are denoted by the same reference numerals, description thereof is omitted, and differences are mainly described below. Explained.

FIG. 7 is a schematic diagram showing the main software configuration of the terminal 31.
FIG. 8 is a diagram illustrating the previous positioning position P1 and the like.
Unlike the terminal 30 of the first embodiment having the estimated travel distance information generation program 116 (see FIG. 3), the terminal 31 of the second embodiment differs from the previous positioning position information stored in the terminal 31. It is determined whether to output the positioning result of the two-dimensional positioning based on the previous altitude information 156b using the previous positioning error information and the current positioning position information and the current positioning error information held without being output by the terminal 31. To do.

The estimated travel distance information 164 (see FIG. 3) generated by the terminal 30 according to the first embodiment is generated based on the assumed travel speed of the terminal 30 and the elapsed time from the previous positioning, for example. Depending on the actual moving speed of 30, the estimated moving distance may be greatly different from the actual moving distance.
In this regard, the terminal 31 according to the second embodiment generates the current estimation error information 170 based on the previous positioning position information 156 and the current positioning position information 152 that are actually measured and held. The terminal 31 is not affected by the actual moving speed or elapsed time.
For this reason, highly accurate latitude information and longitude information can be output in two-dimensional positioning without being affected by the actual moving speed or elapsed time of the terminal 31.
Hereinafter, the configuration and the like of the terminal 31 will be described focusing on differences from the terminal 30 of the first embodiment.

As illustrated in FIG. 7, the terminal 31 stores a current positioning position information acquisition program 124 in the first storage unit. The current positioning position information acquisition program 124 is information for the terminal control unit 100 to acquire the current positioning position information 152. That is, the current positioning position information acquisition program 124 and the terminal control unit 100 are an example of current positioning position information acquisition means.
The current positioning position information 152 is information indicating the current positioning position P2 in FIG.

The terminal 31 also has a current positioning error information acquisition program 126. The current positioning error information acquisition program 126 is information for the terminal control unit 100 to acquire the current positioning error information 154. That is, the current positioning error information acquisition program 126 and the terminal control unit 100 are an example of current positioning error information acquisition means.
The current positioning error information 154 is information indicating the current positioning error distance d5 (see FIG. 8). The current positioning estimation error distance d5 is determined by the reception environment of the terminal 31, for example, if the terminal 31 is located outdoors and the reception sensitivity of the signal S1 from the GPS satellite 12a is good, for example, 10 meters (m). For example, if the terminal 31 is located indoors and the reception sensitivity of the signal S1 from the GPS satellite 12a or the like is low, it is 100 meters (m), for example.

As shown in FIG. 7, the terminal 31 also has a current time estimation error information generation program 128. The current time estimation error information generation program 128 is configured to allow the terminal control unit 100 to perform a current time estimation error distance indicating a current time estimation error distance based on the previous positioning position information 156, the previous positioning error information 160, the current positioning position information 152, and the current positioning error information 154. This is information for generating error information 170. That is, the current estimated error information generation program 128 and the terminal control unit 100 are an example of current estimated error information generating means.
Based on the current estimated error information generation program 128, the terminal control unit 100 determines the previous positioning error distance d1 in FIG. 8 shown in the previous positioning error information 160, the previous positioning position P1 shown in the previous positioning position information 156, and the current positioning. By adding the distance d4 between the current positioning position P2 indicated by the position information 152 and the current positioning error distance d5 indicated by the current positioning estimation error information 154, current estimation error information 170 indicating the current estimation error distance d6 is obtained. Generate.
The terminal control unit 100 stores the generated current estimation error information 170 in the third storage unit 150.

As shown in FIG. 7, the terminal 31 also has a current estimation error threshold value judgment program 130. Based on the previous altitude effective threshold information 142 and the current estimated error information 170 stored in advance by the terminal control unit 100, the current estimated error threshold judgment program 130 determines that the current estimated error distance d6 in FIG. This is information for determining whether or not it is equal to or lower than the previous altitude effective threshold indicated by 142. The previous altitude effective threshold information 142 is also an example of current estimated error allowable range information indicating an allowable range of the current estimated error distance d6. The terminal 31 determines whether or not the current estimated error distance d6 is within an allowable range based on whether or not the current estimated error distance d6 is equal to or less than the previous altitude effective threshold value indicated in the previous altitude effective threshold information 142.
That is, the current estimated error threshold determination program 130 and the terminal control unit 100 are an example of a current estimated error allowable range inside / outside determination means.
For example, the previous estimated error distance d1 (see FIG. 8) is 10 meters (m), and the distance d4 between the previous positioning position P1 and the current positioning position P2 in FIG. 8 is 14,000 meters (m). If the current positioning estimation error distance d5 is 100 meters (m), the current estimation error distance d6 is 14,110 meters (m). For example, if the previous altitude effective threshold indicated in the previous altitude effective threshold information 142 is 20 kilometers (km), the terminal control unit 100 determines that the current estimated error distance d6 is equal to or less than the previous altitude effective threshold.

  As shown in FIG. 7, the terminal 31 also has a positioning result output program 132. When the terminal control unit 100 determines that the current estimated error distance d6 in FIG. 8 is less than or equal to the previous altitude effective threshold, the positioning result output program 132 displays the current position information indicating the current position measured by the display unit 106. Is information for outputting. That is, the positioning result output program 132, the terminal control unit 100, and the display unit 106 are an example of current position information output means.

(Regarding the operation example of the terminal 31 of the second embodiment)
Although the terminal 31 is configured as described above, an example of its operation will be described below.
9 and 10 are schematic flowcharts showing an operation example of the terminal 31.

  When the terminal 31 executes steps ST1 to ST4 as in the terminal 30 of the first embodiment, the terminal 31 acquires current positioning position information 152 (see FIG. 7) indicating the current positioning position (step ST101 in FIG. 9). . That is, step ST101 is an example of a current positioning position information acquisition step.

  Subsequently, the terminal 31 acquires current positioning error information 154 (see FIG. 7) indicating the current positioning estimation error distance d5 of the current positioning position P2 in FIG. 8 (step ST102 in FIG. 10). That is, step ST102 is an example of a current positioning error information acquisition step.

  Subsequently, the terminal 31 calculates the current estimated error distance d6 in FIG. 8 based on the previous positioning position information 156, the previous positioning error information 160, the current positioning position information 152, and the current positioning error information 154 in FIG. The estimated current error information 170 (see FIG. 7) is generated (step ST103). That is, step ST103 is an example of a current estimated error information generation step.

  Subsequently, the terminal 31 determines that the current estimated error distance d6 in FIG. 8 is the previous altitude effective threshold information 142 based on the previous altitude effective threshold information 142 (see FIG. 7) stored in advance and the current estimated error information 170 described above. It is determined whether or not it is equal to or less than the previous altitude effective threshold shown in (ST104). The terminal 31 determines whether or not the current estimated error distance d6 is within the allowable range based on whether or not the current estimated error distance d6 is equal to or less than the previous altitude effective threshold value indicated in the previous altitude effective threshold information 142. That is, step ST104 is an example of a current estimated error distance allowable range inside / outside determination step.

If the terminal 31 determines that the current estimated error distance d6 is less than or equal to the previous altitude effective threshold in step ST104, the terminal 31 obtains the current position information indicating the current position acquired in step ST2, which is an example of the positioning step. Output (step ST9). That is, step ST9 is an example of a position information output step.
As described above, the terminal 31 can output highly accurate latitude information and longitude information in two-dimensional positioning without being affected by the actual moving speed or elapsed time.

(About programs and computer-readable recording media)
In the computer, in the above-described operation example, the positioning possible reception sensitivity satellite number determination step, positioning step, previous positioning error information acquisition step, estimated movement distance information generation step, current estimation error information generation step, and current estimation error allowable range A control program for the terminal device for executing the inside / outside determination step, the current position information output step, and the like can be provided.
Further, the computer can determine the number of positioning-sensitive reception sensitivity satellites in the above operation example, the positioning step, the previous positioning error information acquisition step, the current positioning position information acquisition step, the current positioning error information acquisition step, and the current estimation error. It can be set as the control program of the terminal device for performing an information generation step, a present estimation error permissible range inside / outside judgment step, a position information output step, etc.
Furthermore, a computer-readable recording medium in which such a terminal device control program is recorded can be used.

  A program storage medium used for installing the control program of the terminal device in the computer and making it executable by the computer is, for example, a floppy disk such as a floppy (registered trademark), a CD-ROM (Compact Disc Read Only). Semiconductor memory in which not only package media such as Memory, CD-R (Compact Disc-Recordable), CD-RW (Compact Disc-Rewriteable), DVD (Digital Versatile Disc), but also programs are temporarily or permanently stored It can be realized with a magnetic disk or a magneto-optical disk.

  The present invention is not limited to the embodiments described above. Furthermore, the above-described embodiments may be combined with each other.

It is the schematic which shows the terminal etc. which are embodiment of this invention. It is the schematic which shows the main hardware constitutions of a terminal. It is the schematic which shows the main software structures etc. of a terminal. It is a figure which shows the last positioning position. It is a schematic flowchart which shows the operation example of a terminal. It is a schematic flowchart which shows the operation example of a terminal. It is the schematic which shows the main software structures etc. of a terminal. It is a figure which shows the last positioning position. It is a schematic flowchart which shows the operation example of a terminal. It is a schematic flowchart which shows the operation example of a terminal.

Explanation of symbols

  12a, 12b, 12c, 12d ... GPS satellites, 30, 31 ... terminals. 33 ... Positioning device, 34 ... CPU, 36 ... Storage device, 40 ... Signal receiving device, 42 ... Measuring device, 46 ... Display device, 48 ... Clock, 100 ... .. Terminal control unit, 112 positioning-possible satellite number determination program, 114... Initial position information input program, 116... Estimated movement distance information generation program, 118. Current estimation error threshold value judgment program, 122, 132 ... positioning result output program, 142 ... previous altitude effective threshold information, 152 ... current positioning position information, 156 ... previous positioning position information, 160 ... Previous positioning error information, 162 ... Elapsed time information, 164 ... Estimated travel distance information, 166 ... Current positioning error information, 170 ... Current estimation error information

Claims (12)

A terminal device having positioning means for receiving a position-related signal from a position information satellite and positioning a current position,
The terminal device
Positioning capable reception sensitivity satellite number judging means for judging the number of the position information satellites capable of receiving the position related signal having the positioning sensitivity.
Previous positioning position information storage means for storing previous positioning position information including previous altitude information indicating the altitude of the previous positioning position;
Initial position information input means for using the previous positioning position information as initial position information for positioning the current position;
Previous positioning error information storage means for storing previous positioning error information indicating a positioning error of the previous positioning position;
Based on the elapsed time from the previous positioning, estimated travel distance information generating means for generating estimated travel distance information indicating the estimated travel distance in the elapsed time;
Current estimated error information generating means for generating current estimated error information indicating a current estimated error based on the previous positioning error information and the estimated movement distance information;
Current estimation error allowable range information storage means for storing current estimation error allowable range information indicating an allowable range of the current estimation error;
Use allowable range inside / outside determination means for determining whether or not the current estimation error is within the allowable range, and
A terminal device that outputs current position information indicating the current position when it is determined that the current estimation error is within the allowable range.   The previous position information is positioning position information at the time of three-dimensional positioning in which the positioning means performs three-dimensional positioning by receiving the position-related signals from four or more position information satellites. The terminal device according to 1.   3. The terminal device according to claim 1, wherein the positioning unit performs three-dimensional positioning when the position-related signal can be received from four or more of the position information satellites. . A terminal device having positioning means for receiving a position-related signal from a position information satellite and positioning the current position determines the number of the position information satellites that can receive the position-related signal with a receiving sensitivity capable of positioning. The step of determining the number of satellites with receivable positioning sensitivity,
A positioning step in which the terminal device measures the current position using the previous positioning position information including the previous altitude information indicating the altitude of the previous positioning position as initial position information;
A previous positioning error information acquisition step in which the terminal device acquires previous positioning error information indicating a positioning error of the previous positioning position;
An estimated movement distance information generating step in which the terminal device generates estimated movement distance information indicating an estimated movement distance in the elapsed time based on an elapsed time from the previous positioning;
A current estimated error information generating step in which the terminal device generates current estimated error information indicating a current estimated error based on the previous positioning error information and the estimated moving distance information;
The terminal device determines whether or not the current estimated error is within an allowable range of the current estimated error;
If the terminal device determines that the current estimation error is within the allowable range, a current position information output step for outputting current position information indicating the current position acquired in the positioning step;
A control method for a terminal device, comprising:   5. The previous position information is position information at the time of three-dimensional positioning in which the positioning means performs three-dimensional positioning by receiving the position-related signals from four or more position information satellites. The control method of the terminal device as described in 2.   6. The terminal device according to claim 4, wherein the positioning unit performs three-dimensional positioning when the position-related signal can be received from four or more of the position information satellites. Control method. On the computer,
A terminal device having positioning means for receiving a position-related signal from a position information satellite and positioning the current position determines the number of the position information satellites that can receive the position-related signal with a receiving sensitivity capable of positioning. The step of determining the number of satellites with receivable positioning sensitivity,
A positioning step in which the terminal device measures the current position using the previous positioning position information including the previous altitude information indicating the altitude of the previous positioning position as initial position information;
A previous positioning error information acquisition step in which the terminal device acquires previous positioning error information indicating a positioning error of the previous positioning position;
An estimated movement distance information generating step in which the terminal device generates estimated movement distance information indicating an estimated movement distance in the elapsed time based on an elapsed time from the previous positioning;
The terminal device generates current estimation error information indicating current estimation error information based on the previous positioning error information and the estimated travel distance information;
The terminal device determines whether or not the current estimated error is within an allowable range of the current estimated error;
If the terminal device determines that the current estimation error is within the allowable range, a current position information output step for outputting current position information indicating the current position acquired in the positioning step;
A control program for a terminal device, characterized in that On the computer,
A terminal device having positioning means for receiving a position-related signal from a position information satellite and positioning the current position determines the number of the position information satellites that can receive the position-related signal with a receiving sensitivity capable of positioning. The step of determining the number of satellites with receivable positioning sensitivity,
A positioning step in which the terminal device measures the current position using the previous positioning position information including the previous altitude information indicating the altitude of the previous positioning position as initial position information;
A previous positioning error information acquisition step in which the terminal device acquires previous positioning error information indicating a positioning error of the previous positioning position;
An estimated movement distance information generating step in which the terminal device generates estimated movement distance information indicating an estimated movement distance in the elapsed time based on an elapsed time from the previous positioning;
The terminal device generates current estimation error information indicating current estimation error information based on the previous positioning error information and the estimated travel distance information;
The terminal device determines whether or not the current estimated error is within an allowable range of the current estimated error;
If the terminal device determines that the current estimation error is within the allowable range, a current position information output step for outputting current position information indicating the current position acquired in the positioning step;
A computer-readable recording medium on which a control program for a terminal device is recorded. A terminal device having positioning means for receiving a position-related signal from a position information satellite and positioning a current position,
The terminal device
Positioning capable reception sensitivity satellite number judging means for judging the number of the position information satellites capable of receiving the position related signal having the positioning sensitivity.
Previous positioning position information storage means for storing previous positioning position information including previous altitude information indicating the altitude of the previous positioning position;
Initial position information input means for using the previous positioning position information as initial position information for positioning the current position;
Previous positioning error information storage means for storing previous positioning error information indicating a positioning error of the previous positioning position;
Current positioning position information acquisition means for acquiring current positioning position information indicating the current positioning position;
Current positioning error information acquisition means for acquiring current positioning error information indicating a current positioning error of the current position;
Current estimation error information generating means for generating current estimation error information indicating a current estimation error based on the previous positioning position information, the previous positioning error information, the current positioning position information, and the current positioning error information;
Current estimation error tolerance range information storage means for storing current estimation error tolerance range information indicating the tolerance of the current estimation error;
A current estimation error allowable range inside / outside determination means for determining whether or not the current estimation error is within the allowable range, and
A terminal device that outputs current position information indicating the current position when it is determined that the current time estimation error is within the allowable range.   The previous positioning position information is position information at the time of three-dimensional positioning in which the positioning means performs three-dimensional positioning by receiving the position-related signals from four or more position information satellites. 9. The terminal device according to 9. A terminal device having positioning means for receiving a position-related signal from a position information satellite and positioning the current position determines the number of the position information satellites that can receive the position-related signal with a receiving sensitivity capable of positioning. The step of determining the number of satellites with receivable positioning sensitivity,
A positioning step in which the terminal device measures the current position using the previous positioning position information including the previous altitude information indicating the altitude of the previous positioning position as initial position information;
A previous positioning error information acquisition step in which the terminal device acquires previous positioning error information indicating a positioning error of the previous positioning position;
The terminal device acquires current positioning position information for acquiring current positioning position information indicating the current positioning position; and
A current positioning error information acquisition step in which the terminal device acquires current positioning error information indicating a current positioning error of the current positioning position;
Current terminal estimation error information generating step in which the terminal device generates current estimation error information indicating a current estimation error based on the previous positioning position information, the previous positioning error information, the current positioning position information, and the current positioning error information. When,
The terminal device determines whether or not the current estimated error is within an allowable range of the current estimated error;
When the terminal device determines that the current estimation error is within the allowable range, a position information output step for outputting current position information indicating the current position acquired in the positioning step;
A control method for a terminal device, comprising: The previous positioning position information is position information at the time of three-dimensional positioning in which the positioning means performs three-dimensional positioning by receiving the position-related signals from four or more position information satellites. The control method of the terminal device of 11.

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