JP2009229293A - Positioning method, program, and positioning device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To output a position near to a more true position by preventing deterioration of positioning precision caused by a time difference between measuring timing and output timing. <P>SOLUTION: A positioning method intermittently measures a current position and a speed vector of a cellular phone 1 based on GPS satellite signals. The positioning method calculates a time difference between a measuring time and the output time of a measuring result, and estimates a position at an output time by using a measured position, a measured speed vector and a calculated time difference. The positioning method outputs to determine an output position by using an estimated position. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a positioning method and the like executed by a positioning device.

  As a measurement system using an artificial satellite, a GPS (Global Positioning System) is widely known, and is used in a positioning device built in a mobile phone, a car navigation device, or the like. In GPS, the values of four parameters, the three-dimensional coordinate value indicating the position of the self-positioning device and the clock error, are used as information such as the position of a plurality of GPS satellites and the pseudo distance from each GPS satellite to the self-positioning device. The current position of the self-positioning device is measured by performing the positioning calculation obtained based on it. Also, the velocity vector of the self-positioning device can be measured based on the relative positional relationship between the GPS satellite and the self-positioning device.

However, in measurement using satellite signals from positioning satellites, there are various error factors such as so-called multipath effects, and it is difficult to avoid the occurrence of measurement errors. Various techniques have been devised. As an example, Patent Document 1 discloses a technique for determining an output position by weighted average calculation of a positioning position calculated by positioning calculation and a dead reckoning navigation calculation position calculated by dead reckoning calculation.
JP-A-8-68651

  By the way, the timing at which the current position and velocity vector are measured using satellite signals from the positioning satellite (hereinafter referred to as “measurement timing”), and the timing at which the position is actually output (hereinafter referred to as “output timing”). A slight time difference occurs.

  In the technique disclosed in Patent Document 1, the output position is simply determined by performing a weighted average calculation of the positioning position calculated by the positioning calculation and the dead reckoning calculation position calculated by the dead reckoning calculation. These two positions are positions calculated at different timings. For this reason, due to the time difference between the measurement timing and the output timing, there has been a problem in that the positioning accuracy is deteriorated, which is called a position delay in which the output position is delayed with respect to the true position of the positioning device.

  The present invention has been made in view of the above-described problems, and the object of the present invention is to prevent the deterioration of positioning accuracy due to the time difference between the measurement timing and the output timing, and is closer to the true position. The position is to be output.

  1st invention for solving the above subject is the positioning method which a positioning device performs, Comprising: The position of the self-positioning device and the speed of the self-positioning device based on the positioning signal transmitted from the positioning satellite Measuring the vector intermittently; calculating a time difference between the timing of the measurement and the output timing of the positioning result; and measuring the measured position, the measured velocity vector, and the calculated time difference. Is used to estimate the position at the output timing, and determine and output the output position using the estimated position.

  As another invention, a measurement unit that intermittently measures the position of the self-positioning device and the velocity vector of the self-positioning device based on a positioning signal transmitted from a positioning satellite, and the timing and result of the measurement A time difference calculating unit that calculates a time difference from the output timing of the output, a position estimation that estimates a position at the output timing using the measured position, the measured velocity vector, and the calculated time difference A positioning device may be configured to include a unit and an output position determination unit that determines and outputs an output position using the estimated position.

  According to the first aspect and the like, the position and velocity vector of the self-positioning device are intermittently measured based on the positioning signal. Then, a time difference between the timing of the measurement and the output timing of the positioning result is calculated, and the position at the output timing is estimated using the measured position, the measured velocity vector, and the calculated time difference. Then, the output position is determined and output using the estimated position.

  Rather than determining the output position using the measured position, the output position is determined using the position at the output timing estimated based on the measured position, so that the time between the measurement timing and the output timing It is possible to prevent the occurrence of a position delay due to the difference, improve the positioning accuracy, and output a position closer to the true position.

  Further, as a second invention, in the positioning method of the first invention, the estimation of the position at the output timing is based on the latest and past acceleration results at the latest measurement. Using the latest velocity vector obtained by the latest measurement, the calculated acceleration vector, and the calculated time difference, and estimating the velocity vector at the output timing. A positioning method that includes estimating the position at the output timing using the latest position obtained by the latest measurement, the estimated velocity vector, and the calculated time difference; Also good.

  According to the second invention, the velocity vector at the output timing is estimated using the latest velocity vector, the acceleration vector at the latest measurement, and the time difference between the measurement timing and the output timing of the positioning result. . Then, the position at the output timing is estimated using the latest position, the estimated velocity vector, and the time difference between the measurement timing and the output timing of the positioning result.

  Further, as a third invention, the positioning method according to the second invention, wherein the position at the output timing is estimated by using the estimated velocity vector as the latest velocity vector obtained by the latest measurement. Using the latest position obtained by the latest measurement, the smoothed velocity vector, and the calculated time difference to estimate the position at the output timing. You may comprise the positioning method which is.

  According to the third aspect of the invention, the estimated speed vector is smoothed using the latest speed vector. Then, the position at the output timing is estimated using the latest position, the smoothed velocity vector, and the time difference between the measurement timing and the output timing of the positioning result.

  Further, as a fourth invention, in the positioning method according to any one of the first to third inventions, the determination of the output position is performed by a predetermined dead reckoning calculation using the past output position. You may comprise the positioning method including calculating the dead reckoning calculation position which is a position of an apparatus, and determining an output position using the estimated position and the dead reckoning calculation position.

  According to the fourth invention, the dead reckoning calculation position is calculated by the predetermined dead reckoning calculation using the past output position, and the output position is determined using the estimated position and the dead reckoning calculation position.

  Further, as a fifth invention, the positioning method according to the fourth invention, wherein the determination of the output position includes weighting between the estimated position and the dead reckoning calculation position as the calculated time difference. A positioning method may be configured in which the output position is determined by a predetermined weighted average calculation that is variably set based on.

  According to the fifth aspect of the invention, weighting between the estimated position and the dead reckoning calculation position is performed by a predetermined weighted average calculation that is variably set based on the time difference between the measurement timing and the output timing of the positioning result. The output position is determined. By performing weighted average calculation with variable weighting based on the time difference between measurement timing and positioning result output timing, appropriate position output can be performed regardless of the measurement environment. Is possible.

  Further, as a sixth invention, a program for causing a computer incorporated in the positioning device to execute the positioning method of any one of the first to fifth inventions may be configured.

  Hereinafter, with reference to the drawings, an embodiment in which the present invention is applied to a mobile phone which is a kind of electronic apparatus including a positioning device will be described. However, embodiments to which the present invention can be applied are not limited to this.

1. Functional Configuration FIG. 1 is a block diagram showing a functional configuration of a mobile phone 1 according to this embodiment. The mobile phone 1 includes a GPS antenna 5, a GPS receiving unit 10, a host CPU (Central Processing Unit) 30, an operation unit 40, a display unit 50, a mobile phone antenna 60, and a mobile phone radio communication circuit. A unit 70, a ROM (Read Only Memory) 80, and a RAM (Random Access Memory) 90 are provided.

  The GPS antenna 5 is an antenna that receives an RF (Radio Frequency) signal including a GPS satellite signal transmitted from a GPS satellite, and outputs the received signal to the GPS receiving unit 10. The GPS satellite signal is a 1.57542 [GHz] communication signal modulated by a direct spread spectrum system with a PRN (Pseudo Random Noise) code which is a kind of spreading code different for each satellite. The PRN code is a pseudo-random noise code having a repetition period of 1 ms with a code length of 1023 chips as one PN frame.

  The GPS receiver 10 is a positioning circuit that measures the current position of the mobile phone 1 based on a signal output from the GPS antenna 5, and is a functional block corresponding to a so-called GPS receiver. The GPS receiving unit 10 includes an RF (Radio Frequency) receiving circuit unit 11 and a baseband processing circuit unit 20. The RF receiving circuit unit 11 and the baseband processing circuit unit 20 can be manufactured as separate LSIs (Large Scale Integration) or can be manufactured as one chip.

  The RF receiving circuit unit 11 is an RF signal processing circuit block, and generates an oscillation signal for RF signal multiplication by dividing or multiplying a predetermined local oscillation signal. Then, by multiplying the generated oscillation signal by the RF signal output from the GPS antenna 5, the RF signal is down-converted to an intermediate frequency signal (hereinafter referred to as an "IF (Intermediate Frequency) signal"), After the IF signal is amplified, it is converted into a digital signal by an A / D converter and output to the baseband processing circuit unit 20.

  The baseband processing circuit unit 20 performs correlation processing on the IF signal output from the RF receiving circuit unit 11 to capture and extract GPS satellite signals, decodes the data, and extracts navigation messages, time information, and the like. This is a circuit unit that performs positioning calculation. The baseband processing circuit unit 20 includes a satellite capturing / tracking unit 21, a CPU 23, a ROM 25, and a RAM 27.

  The satellite capturing / tracking unit 21 is a circuit unit that captures and tracks a GPS satellite signal based on the IF signal output from the RF receiving circuit unit 11. For acquisition of GPS satellite signals, for each GPS satellite to be acquired, a correlation value between a diffusion code (replica PRN code) generated artificially inside the apparatus and the IF signal is calculated, and a frequency component having the largest amplitude is obtained. And a correlation process for extracting the phase component.

  The host CPU 30 is a processor that comprehensively controls each unit of the mobile phone 1 according to various programs such as a system program stored in the ROM 80. The host CPU 30 causes the display unit 50 to display a navigation screen in which the output position input from the CPU 23 is plotted.

  The operation unit 40 is an input device configured by a touch panel, a button switch, or the like, for example, and outputs a pressed icon or button signal to the host CPU 30. By operating the operation unit 40, various instructions such as a call request, a mail transmission / reception request, and a GPS activation request are input.

  The display unit 50 is configured by an LCD (Liquid Crystal Display) or the like, and is a display device that performs various displays based on display signals input from the host CPU 30. The display unit 50 displays a navigation screen, time information, and the like.

  The cellular phone antenna 60 is an antenna that transmits and receives cellular phone radio signals to and from a radio base station installed by a communication service provider of the cellular phone 1.

  The cellular phone wireless communication circuit unit 70 is a cellular phone communication circuit unit configured by an RF conversion circuit, a baseband processing circuit, and the like, and performs modulation and demodulation of the cellular phone radio signal, thereby enabling communication and mailing. Realize transmission / reception of

  The ROM 80 is a read-only nonvolatile storage device, and stores a system program for the host CPU 30 to control the mobile phone 1 and various programs and data for realizing a navigation function.

  The RAM 90 is a readable / writable volatile storage device, and forms a work area for temporarily storing a system program executed by the host CPU 30, various processing programs, data being processed in various processing, processing results, and the like. .

2. Data Configuration FIG. 2 is a diagram illustrating an example of data stored in the ROM 25 of the baseband processing circuit unit 20. The ROM 25 stores a baseband processing program 251 that is executed as baseband processing (see FIG. 6).

  In the baseband processing, the CPU 23 outputs a GPS positioning position and velocity vector measured by performing GPS measurement processing, the latest measurement time (hereinafter referred to as “latest measurement time”), and the current measurement position output. The position at the current output time is estimated using the time difference from the time (hereinafter referred to as “current output time”), and the estimated position is weighted with the dead reckoning calculation position calculated by dead reckoning calculation This is a process for determining the output position by averaging. The baseband process will be described later in detail using a flowchart.

  FIG. 3 is a diagram illustrating an example of data stored in the RAM 27. The RAM 27 stores satellite data 271, measurement history data 273, measurement time difference data 275, and measurement output time difference data 277.

  FIG. 4 is a diagram illustrating an example of the data configuration of the satellite data 271. In the satellite data 271, a satellite velocity vector 2712 and a satellite position 2713 are stored in association with each captured satellite 2711 captured by the satellite capture / tracking unit 21. The satellite velocity vector 2712 is represented, for example, as a three-dimensional vector in the earth reference coordinate system, and the satellite position 2713 is represented, for example, as a three-dimensional coordinate value in the earth reference coordinate system. The satellite data 271 is used for the CPU 23 to perform GPS measurement processing in the baseband processing.

  FIG. 5 is a diagram illustrating an example of the data configuration of the measurement history data 273. In the measurement history data 273, time 2731, time type 2732, velocity vector 2733, acceleration vector 2734, GPS positioning position 2735, estimated position 2736, dead reckoning calculation position 2737, and output position 2738 correspond to each other. This data is stored together and updated by the CPU 23 in the baseband processing.

  The time type 2732 is a type of the time 2731, and “measurement” or “output” is stored depending on whether the time 2731 is a measurement time or an output time. In the case of the same time, two data of “measurement” and “output” are stored in the measurement history data 273, “measurement” is stored in one and “output” is stored in the other. Become. A time whose time type is “measurement” is referred to as “measurement time”, and a time whose time type is “output” is referred to as “output time”.

  The speed vector 2733 is a three-dimensional speed vector of the mobile phone 1, and the speed vector measured by the GPS measurement process at the measurement time is stored for the measurement time. For the output time, the speed vector at the output time obtained by correcting the speed vector at the measurement time is stored.

  The acceleration vector 2734 is a three-dimensional acceleration vector of the mobile phone 1, and the acceleration vector calculated based on the velocity vector at the measurement time is stored for the measurement time. Further, since the acceleration vector is not calculated for the output time, “− (none)” is stored in the acceleration vector 2734.

  The GPS positioning position 2735 stores the three-dimensional position of the mobile phone 1 measured by the GPS measurement process at the measurement time. As for the output time, since the position is not measured by the GPS measurement process, “-(none)” is stored in the GPS positioning position 2735.

  The estimated position 2736 stores the three-dimensional position of the mobile phone 1 at the output time estimated based on the GPS positioning position 2735, the speed vector 2733, and the time difference between the measurement time and the output time. The Since the position is not estimated for the measurement time, “-(none)” is stored in the estimated position 2736.

  The dead reckoning calculation position 2737 stores the three-dimensional position of the mobile phone 1 at the output time calculated by dead reckoning calculation processing. Since the dead reckoning calculation processing is not performed for the measurement time, “-(none)” is stored in the dead reckoning calculation position 2737.

  The output position 2738 stores a three-dimensional position of the mobile phone 1 calculated by performing a weighted average calculation of the estimated position 2736 and the dead reckoning calculation position 2737. Since the output position is not calculated for the measurement time, “-(none)” is stored in the output position 2738.

  In this embodiment, it is assumed that the output time is in principle a predetermined time interval (for example, one second interval). In addition, when a sufficient number of GPS satellite signals for measurement are not captured by the satellite capture / tracking unit 21 due to the influence of the positioning environment or the like, the GPS measurement process cannot be performed, so the measurement time is predetermined. It is not always a time interval. For example, in the measurement history data 273 of FIG. 5, the times “tp3” to “tp5” are all output times, which means that the GPS measurement process could not be performed during this time.

  The measurement time difference data 275 is data of a time difference between the latest measurement time and the previous measurement time (hereinafter referred to as “measurement time difference”), and is updated by the CPU 23 in the baseband process.

  The measurement output time difference data 277 is data of a time difference between the latest measurement time and the current output time (hereinafter referred to as “measurement output time difference”), and is updated by the CPU 23 in the baseband processing.

3. Processing Flow FIG. 6 is a flowchart showing the flow of baseband processing executed in the mobile phone 1 when the CPU 23 reads out and executes the baseband processing program 251 stored in the ROM 25.

  The baseband process is a process that starts execution when the CPU 23 detects that a positioning start instruction has been operated on the operation unit 40 together with the reception of the GPS satellite signal by the RF reception circuit unit 11. Note that the baseband processing may be started when the power-on operation of the mobile phone 1 is detected by linking the power-on / off of the mobile phone 1 and the activation / stop of GPS.

  First, the CPU 23 calculates the satellite velocity vector 2712 and the satellite position 2713 of each captured satellite 2711 based on the navigation message superimposed on the GPS satellite signal captured by the satellite capture / tracking unit 21, and stores the RAM 27 as satellite information. Is stored in the satellite data 271 (step A1).

  Next, the CPU 23 performs GPS measurement processing (step A3). Specifically, based on the satellite information calculated in step A1, a GPS positioning position 2735 is obtained by performing positioning calculation using, for example, the least square method. Further, the speed vector 2733 of the mobile phone 1 is obtained based on the relative speed between the captured satellite and the mobile phone 1. Then, the obtained GPS positioning position 2735 and velocity vector 2733 are stored in the measurement history data 273 of the RAM 27 in association with the current time 2731 and time type 2732.

  Next, the CPU 23 calculates a time difference between the latest measurement time stored in the measurement history data 273 and the previous measurement time as a measurement time difference (step A5), and the measurement time difference data 275 in the RAM 27. Update. Further, the CPU 23 calculates a time difference between the latest measurement time and the current output time to obtain a measurement output time difference (step A7), and updates the measurement output time difference data 277 in the RAM 27.

但し、「Ａ（ｔ）」は時刻「ｔ」における加速度ベクトル、「Ｖ（ｔ）」は時刻「ｔ」における速度ベクトル、「ｔ_m」は計測時刻、「Δｔ_m」は計測時刻差をそれぞれ示している。 Thereafter, the CPU 23 calculates the acceleration vector 2734 of the mobile phone 1 at the latest measurement time according to the following equation (1) (step A9) and stores it in the measurement history data 273.

However, “A (t)” is the acceleration vector at time “t”, “V (t)” is the velocity vector at time “t”, “t _m ” is the measurement time, and “Δt _m ” is the measurement time difference. Show.

但し、「ｔ_p」は出力時刻、「Δｔ_p」は計測出力時刻差をそれぞれ示している。 Next, the CPU 23 estimates the speed vector 2733 of the mobile phone 1 at the current output time according to the following equation (2) (step A11) and stores it in the measurement history data 273.

However, “t _p ” indicates the output time, and “Δt _p ” indicates the measurement output time difference.

但し、「Ｐ_a（ｔ）」は時刻「ｔ」における推定位置、「Ｐ_g（ｔ）」は時刻「ｔ」におけるＧＰＳ測位位置をそれぞれ示している。 Then, the CPU 23 calculates an estimated position 2736 at the current output time according to the following equation (3) (step A13) and stores it in the measurement history data 273.

However, “P _a (t)” indicates the estimated position at time “t”, and “P _g (t)” indicates the GPS positioning position at time “t”.

As can be seen from Equation (3), in this embodiment, the GPS positioning position “P _g (t _m )” at the latest measurement time and the velocity vector “V (t _p )” at the current output time are used as the velocity at the latest measurement time. using the vector "V (t _m)" smoothed velocity vector using the _{"(V (t p) + V} (t m)) / 2 ", the measurement output time difference and "Delta] t _p", this output time The estimated position “P _a (t _p )” is calculated.

但し、「Ｐ_r（ｔ）」は時刻「ｔ」における推測航法演算位置、「Ｐ（ｔ）」は時刻「ｔ」における出力位置をそれぞれ示している。 Next, the CPU 23 performs dead reckoning calculation according to the following equation (4), calculates the dead reckoning operation position 2737 at the current output time (step A15), and stores it in the measurement history data 273.

However, “P _r (t)” represents the dead reckoning calculation position at time “t”, and “P (t)” represents the output position at time “t”.

Thereafter, the CPU 23 calculates a weight “α” for weighted average calculation between the estimated position calculated in step A13 and the dead reckoning calculation position calculated in step A15 (step A17). The weight “α” is expressed as a function of the measurement output time difference “Δt _p ”. For example, as shown in FIG. 7, “Δt _p ” increases by “1.0” when “Δt _p = 0”. It is expressed as an exponential function that gradually decreases with time. Note that a function other than the exponential function (for example, a linear function) may be used as long as “Δt _p ” increases gradually.

Next, the CPU 23 performs a weighted average calculation of the estimated position and the dead reckoning navigation calculation position according to the following equation (5) based on the weight “α” calculated in step A17, and determines the output position 2738 at the current output time. (Step A19), and stored in the measurement history data 273.

From equation (5), it can be seen that as the weight “α” is smaller, the position closer to the estimated position is determined as the output position. Therefore, from the relationship with the qualitative graph of the weight “α” shown in FIG. 7, the position closer to the estimated position is determined as the output position as the measured output time difference “Δt _p ” increases.

  Thereafter, the CPU 23 outputs the output position determined in step A19 to the host CPU 30 (step A21). Then, the CPU 23 determines whether or not to end the measurement (step A23). If it is determined that the measurement has not ended yet (step A23; No), the CPU 23 returns to step A1. If it is determined that the measurement is to be terminated (step A23; Yes), the baseband processing is terminated.

4). Experimental Result FIG. 8 is a diagram illustrating an example of the experimental result of determining the output position using the method of the present embodiment. Here, the true position and the output position of the mobile phone 1 at each output time when the automobile (sports car) on which the mobile phone 1 is placed stops at the start point in the lower left for 1 minute and then accelerates to 300 km / h. And the result of having plotted the GPS positioning position in each measurement time is shown. The time interval of the output time is 1 second.

  Looking at this figure, it can be seen that the GPS positioning position has a delay of about 0.5 seconds with respect to the true position, but the output position almost coincides with the true position at all output times. It can be seen that an accurate position is output.

5. Effects According to the present embodiment, the current position and velocity vector of the mobile phone 1 are intermittently measured based on the GPS satellite signal. Then, the time difference between the measurement time and the output time of the positioning result is calculated, and the position at the output time is estimated using the measured position, the measured velocity vector, and the calculated time difference. Then, the output position is determined and output using the estimated position.

  Instead of determining the output position using the measured position, the output position is determined using the position at the output time estimated based on the measured position, so that the time difference between the measured time and the output time is determined. It is possible to effectively prevent the occurrence of a position delay due to, improve the positioning accuracy, and output a position closer to the true position.

  In the present embodiment, the output position is determined by performing a weighted average calculation of the estimated position and the dead reckoning calculation position calculated by dead reckoning calculation. Specifically, the weighted average calculation is performed by performing weighting so that the position closer to the estimated position becomes the output position as the measurement output time difference increases. This makes it possible to provide an appropriate output position without being influenced by the measurement environment.

6). Modification 6-1. Electronic Device In the above-described embodiment, a mobile phone has been described as an example of an electronic device provided with a positioning device, but an electronic device to which the present invention can be applied is not limited thereto. For example, the present invention can be applied to electronic devices such as a notebook personal computer equipped with a positioning device, a PDA (Personal Digital Assistant), and a car navigation device.

6-2. In the above-described embodiment, the GPS has been described as an example of the satellite positioning system. However, WAAS (Wide Area Augmentation System), QZSS (Quasi Zenith Satellite System), GLONASS (GLObal NAvigation Satellite System), GALILEO Other satellite positioning systems may be used.

6-3. Differentiation of Processing The host CPU 30 may perform part or all of the processing performed by the CPU 23. For example, the CPU 23 performs GPS measurement processing to measure the current position and velocity vector of the mobile phone 1 and outputs the measured current position and speed vector to the host CPU 30. Then, the host CPU 30 estimates the position at the output time based on the GPS positioning position and velocity vector input from the CPU 23 and the time difference between the measurement time and the output time. Then, the host CPU 30 performs dead reckoning calculation to calculate the dead reckoning calculation position, performs weighted average calculation of the estimated position and the dead reckoning calculation position, and determines the output position. Further, the host CPU 30 may execute it including GPS measurement processing.

6-4. Calculation of Estimated Position In the above-described embodiment, the GPS positioning position “P _g (t _m )” at the latest measurement time and the velocity vector “V (t _p )” at the current output time are converted into the velocity vector “V ( t _m ) ”and using the velocity vector“ (V (t _p ) + V (t _m )) / 2 ”smoothed using“ t _m ”” and the measured output time difference “Δt _p ”, this time output according to equation (3) In the above description, the estimated position “P _a (t _p )” at the time is calculated. However, depending on the embodiment to be applied, the estimated position “P _a (t _p )” may be calculated using the velocity vector “V (t _p )” as it is without performing smoothing. Specifically, the estimated position “P _a (t _p )” is calculated according to the following equation (6).

6-5. Calculation of Dead Reckoning Calculation Position In the above-described embodiment, the dead reckoning calculation position “P _r (t _p )” is calculated according to the equation (4). However, if the measurement time difference “Δt _m ” is constant, the dead reckoning navigation calculation position “P _r ” according to the following equation (7) is used, using the speed vectors measured for a total of four times for the latest and the past three times. (T _p ) ”may be calculated.

The block diagram which shows the function structure of a portable telephone. The figure which shows an example of the data stored in ROM of a baseband process circuit part. The figure which shows an example of the data stored in RAM of a baseband process circuit part. The figure which shows an example of the data structure of satellite data. The figure which shows an example of a data structure of measurement log | history data. The flowchart which shows the flow of a baseband process. Qualitative graph of weighted average calculation weights. The figure which shows an example of an experimental result.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Portable telephone, 5 GPS antenna, 10 GPS receiving part, 11 RF receiving circuit part, 20 Baseband processing circuit part, 21 Satellite capture and tracking part, 23 CPU, 25 ROM, 27 RAM, 30 Host CPU, 40 Operation part 50 display unit, 60 mobile phone antenna, 70 mobile phone wireless communication circuit unit, 80 ROM, 90 RAM

Claims (7)

A positioning method performed by a positioning device,
Intermittently measuring the position of the positioning device and the velocity vector of the positioning device based on the positioning signal transmitted from the positioning satellite;
Calculating a time difference between the timing of the measurement and the output timing of the positioning result;
Estimating the position at the output timing using the measured position, the measured velocity vector, and the calculated time difference;
Determining and outputting an output position using the estimated position; and
Positioning method including. Estimating the position at the output timing is
Calculating an acceleration vector at the latest measurement based on the latest and past measurement results;
Estimating a velocity vector at the output timing using the latest velocity vector obtained by the latest measurement, the calculated acceleration vector, and the calculated time difference;
Using the latest position obtained by the latest measurement, the estimated velocity vector, and the calculated time difference, to estimate the position at the output timing.
The positioning method according to claim 1. Estimating the position at the output timing is
Smoothing the estimated velocity vector with the latest velocity vector determined by the latest measurement;
Using the latest position obtained by the latest measurement, the smoothed velocity vector, and the calculated time difference to estimate the position at the output timing;
The positioning method according to claim 2. Determining the output position includes
Calculating a dead reckoning calculation position which is a position of the self-positioning device by a predetermined dead reckoning calculation using the past output position;
Determining an output position using the estimated position and the dead reckoning calculation position;
including,
The positioning method as described in any one of Claims 1-3.   Determining the output position determines the output position by a predetermined weighted average calculation in which weighting between the estimated position and the dead reckoning calculation position is variably set based on the calculated time difference. The positioning method according to claim 4.   The program for making the computer incorporated in the positioning apparatus perform the positioning method as described in any one of Claims 1-5. A measurement unit that intermittently measures the position of the self-positioning device and the velocity vector of the self-positioning device based on the positioning signal transmitted from the positioning satellite;
A time difference calculator for calculating a time difference between the timing of the measurement and the output timing of the positioning result;
A position estimation unit that estimates a position at the output timing using the measured position, the measured velocity vector, and the calculated time difference;
An output position determining unit that determines and outputs an output position using the estimated position;
Positioning device equipped with.

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