JP3651678B2 - Autonomous positioning method by GPS, autonomous navigation device, and computer program - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a GPS (Global Positioning System) positioning method, and more particularly to an autonomous navigation device that enables real-time independent positioning.
[0002]
[Prior art]
As a positioning method using GPS, there are a single positioning method and a relative positioning method.
In the single positioning method, a GPS receiver is placed at a positioning point, and the GPS receiver simultaneously receives data codes (time, satellite positions) from four or more GPS satellites, and analyzes the data codes for positioning. This is a method for calculating three-dimensional position information (coordinate values) of points.
[0003]
The relative positioning method is a positioning method using a base station whose three-dimensional position information is known and a GPS receiver at a positioning point, and is roughly divided into a differential method and an interference positioning method.
The differential method is a method in which a base station and a GPS receiver each perform independent positioning using a data code and cancel out a common error. On the other hand, in the interference positioning method, the base station and the GPS receiver respectively observe the phase of the carrier wave from the GPS satellite and then obtain the relative position between the known point and the positioning point, thereby obtaining the position information of the positioning point. This is a method to calculate This interference positioning method is also referred to as a real time kinematics (hereinafter, “RTK”) method because position information can be calculated almost in real time even when a positioning point moves.
[0004]
In the RTK method, the path difference between the distance from the base station to the GPS receiver and the distance from the GPS receiver to the four GPS satellites is obtained by sequential calculation. The distance and the path difference can be obtained based on the phase of the carrier wave from the GPS satellite, that is, the carrier wave phase. The carrier wave phase includes a delay error due to the ionosphere and the like, a clock error, and the like.
[0005]
[Problems to be solved by the invention]
The single positioning method is a simple positioning method, but has a large error. On the other hand, in the relative positioning method, particularly the RTK method, an error due to positioning is offset between the observation results of the base station, so that the error is small, but the range in which positioning is possible is limited to the coverage area of the base station.
That is, a positioning device that can be used simply has low accuracy, and a high accuracy device has many restrictions (a base station with a clear time, position, and GPS error is required).
[0006]
An object of the present invention is to provide an autonomous positioning method that enables highly accurate positioning even when a base station is not present.
Another object of the present invention is to provide an autonomous navigation apparatus and a computer program suitable for implementing an autonomous positioning method.
[0007]
[Means for Solving the Problems]
Autonomous positioning process provided by the present invention, a self-positioning method one autonomous navigation device having a GPS receiver and the memory is performed by the autonomous navigation device placed in the positioning point, the GPS a plurality of GPS satellites One GPS actual measurement data is obtained by observation with a receiver, and the estimation of future estimated values based on the current values of the acquired GPS actual measurement data and the values estimated and stored in the past is estimated based on the estimated values. The error covariance is repeated until convergence within a predetermined value, and the estimated value at the time of convergence is stored in the memory as positioning reference information representing the position of the virtual reference station, and the autonomous navigation device is stored in the memory And performing carrier wave positioning at the positioning point using the positioning standard information as reference information.
[0008]
From the viewpoint of further shortening the error convergence time, a combination of four GPS satellites that minimizes the positioning error due to the current value is detected, and each of the detected four GPS satellites is detected at two frequencies by the GPS receiver. One GPS actual measurement data from which the noise component is deleted is acquired by observing and comparing.
The predetermined value is, for example, a value within one wavelength of a carrier wave transmitted by an observed GPS satellite. Thereby, the error can be further reduced by correcting the phase angle.
[0009]
In the autonomous positioning process of the present invention, the autonomous navigation system, for example, processing for calculating, based on the estimated error covariance by value estimated to said current value and historical parameters for enabling the convergence of error values, wherein the current value, processing for calculating by adding the estimated error covariance that corrected based on the present value of the estimated value previously obtained, the error covariance, from the estimated covariance error previously determined covariance by the current value value modified by subtracting the process, the future estimated value, the processing for calculating by modifying using the parameter estimates transition of obtaining the current value up to the previous, the estimated covariance error covariance transitions and indefinite By repeatedly executing the process of calculating by adding a change in value, the value of the estimated error covariance is converged.
[0010]
In the autonomous positioning method of the present invention, for example, when the autonomous navigation device moves the positioning point by recording the positioning result by the carrier positioning when the positioning point moves as new positioning reference information in the memory. Even so, the positioning error does not increase and high-accuracy positioning is possible.
In the carrier positioning, for example, the distance to the plurality of GPS satellites starting from the virtual position specified by the positioning reference information stored in the memory is set to the frequency of the carrier from each GPS satellite and the transmission of the carrier. Calculated by a function of time, and dividing the calculated distance by the frequency of the carrier wave to calculate an integer value bias, and further calculating a phase angle within one wavelength of the carrier wave from the integer value bias; This is a technique for specifying the position of a positioning point based on the length represented by this phase angle.
[0011]
The autonomous navigation apparatus provided by the present invention includes input means for inputting signals of two types of frequencies received by a GPS receiver capable of observing each of a plurality of GPS satellites at two types of frequencies, and input signals from these signals. A pre-processing unit that deletes a noise component common to each frequency to obtain one GPS actual measurement data, and acquires the GPS actual measurement data obtained by the pre-processing unit, and the current value and past of the acquired GPS actual measurement data The calculation of future estimated values based on the estimated and stored values is repeated until the estimated error covariance converges within a predetermined value, and the estimated value obtained as a result is used as positioning reference information. It is an apparatus having positioning standard information generating means stored in a memory and carrier positioning means for performing carrier positioning using the positioning standard information stored in the memory as reference information.
Specifically, the positioning reference information determining means includes a filter unit for minimizing the estimation error covariance, and is configured to calculate the future estimated value by the filter unit.
[0012]
The computer program according to the present invention inputs a computer that can be connected to a GPS receiver capable of observing each of a plurality of GPS satellites at two types of frequencies, and inputs signals of two types of frequencies received by the GPS receiver. preprocessing means for obtaining the one of the GPS measurement data to remove the noise component to be common to the frequency of these signals, acquires the GPS measurement data obtained by the preprocessing means, acquired the GPS measurement data Calculation of the future estimated value based on the current value and the value estimated and stored in the past is repeated until the difference from the current value converges to a predetermined value, and the estimated value obtained thereby is used as positioning reference information. predetermined positioning reference information determining means to store in the memory, the carrier positioning means for performing a carrier positioning that the reference information positioning reference information stored in said memory as a And to function in a computer program.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail.
FIG. 1 is a diagram showing an embodiment in which the autonomous navigation device of the present invention is configured by a positioning device 10 mounted on a computer and a GPS receiver 20 connected to the positioning device 10 via a cable or the like. is there. This autonomous navigation apparatus receives GPS data transmitted from a plurality of GPS satellites (six GPS satellites GS1 to GS6 in the illustrated case), and measures the position of an arbitrary positioning point independently.
[0014]
GPS satellites always transmit data codes necessary for positioning on carrier waves of two frequencies of L1 band (1.5 GHz band) and L2 band (1.2 GHz). The GPS receiver 20 selects four optimal GPS satellites from among these GPS satellites using GDOP (Geometrical Dilution of Precision). GDOP is a deviation of whether or not the GPS satellites used for positioning are in an arrangement with little error with respect to the positioning point. The larger this value, the larger the error between the estimated position value and the actually measured value. The GPS receiver 20 automatically determines an optimal combination that reduces the GDOP.
[0015]
As shown in FIG. 2, the GPS receiver 20 includes a GPS antenna 21 that receives the two types of frequencies transmitted by the GPS satellites GS1 to GS6, and a movement amount when the GPS receiver 20 moves. The movement detection sensor 22 including an accelerometer that detects movement and outputs movement amount data, and receives data from the GPS antenna 21 and the movement detection sensor 22 to perform high-frequency amplification, detection, etc., and information on position, time, etc. A data receiving circuit 23 that outputs GPS data including the data, and an interface circuit 24 for sending GPS data and movement amount data output from the data receiving circuit 23 to the positioning device.
[0016]
The positioning device 10 includes an external storage device, a computer including a processor and a memory, and a display, and a printer is connected as necessary. In this embodiment, the processor reads and executes a positioning program recorded in an external storage device and a basic program such as an operating system, so that functional blocks as shown in FIG. The functions of the GPS data input unit 11, the movement amount data input unit 12, the noise removal unit 13, the filter unit 14, the position coordinate calculation unit 15, the positioning reference information management unit 16, the display image generation unit 18, and the output control unit 19 are realized. In addition to constructing a functional block for this purpose, the positioning reference information storage unit 17 is formed in the external storage device. Preferably, the positioning reference information storage unit 17 is formed in a non-volatile memory area.
[0017]
The GPS data input unit 11 inputs GPS data in time series among signals of two types of frequencies received by the GPS receiver 20, and the movement amount data input unit 12 is a movement detection sensor of the GPS receiver 20. The movement amount data detected at 22 is input.
[0018]
The noise removing unit 13 deletes a noise component common to each frequency from the input GPS data to obtain one GPS actual measurement data. Although the data received from the GPS satellite includes noise such as radio wave delay in the troposphere or ionosphere, noise can be removed by performing simultaneous reception of two frequencies and comparing them.
[0019]
The filter unit 14 performs estimation of the position coordinates of the positioning point based on the GPS measurement data by characteristic filtering.
Estimating the position coordinates of the positioning point from the GPS data itself is also performed in the conventional RTK method, but it takes a lot of time to estimate with high accuracy. That is, in the conventional RTK system, there are seven kinds of unknown parameters, that is, position coordinates (x, y, z) of positioning points and ambiguity (synonymous with integer value bias) of four GPS satellites. FLOAT solution, that is, after estimating the tentative ambiguity by a method of estimating the position coordinates and integer value bias of the positioning point, which is an unknown number, by using the least squares method, additional information from the base station, for example, the distance from the GPS satellite It is necessary to determine the true ambiguity using the position coordinates of the base station, the current time, and the like, which requires a large amount of calculation.
[0020]
On the other hand, in this embodiment, the error of the estimated value is reduced by filtering the GPS actual measurement data which is a single positioning result in the direction in which the error converges. There is no conventional idea of filtering the actually measured values in this way. The filtering according to the present embodiment is a process of repeating the process of calculating a future estimated value from the current value and past estimated value of GPS measured data until the estimated error covariance by the estimated value converges. For example, the convergence point is set to one wavelength (20 to 24 cm) of the carrier wave.
[0021]
A specific parameter configuration example of the filter unit 14 for performing the above filtering is shown in FIG. The filter unit 14 is realized by combining four types of parameters as illustrated.
In FIG. 4, “K” is a parameter provided in the first stage, and is a filter gain that minimizes the covariance in order to obtain an optimum condition of the estimation error value. Specifically, the filter gain K is prepared in the form of a proportional matrix. “F” is a parameter for deriving the estimated value transition obtained up to the previous time, “H” is a parameter for deriving the future estimated value, and “Z ⁻¹ ” derives the past estimated value from the past value. It is a parameter to do. “Vt” is a current value of GPS actual measurement data including an estimated covariance error at time t, ax (t / t) is an estimated value at the current time (t), and “ax (t / t− 1) "is a past estimated value estimated from the estimated value at the present time (t), and" ax (t-1 / t-1) "is a past estimated value estimated from the value of the previous measurement (t-1). .
[0022]
There is nothing that can be said to be a true value in GPS measurement data input in time series. These GPS measurement data are obtained by superimposing a noise component added in the propagation process on a data component that is a true value. The filter unit 14 decomposes the noise component as much as possible in consideration of the error between the past estimated value and the current value, and extracts only the data component.
[0023]
In FIG. 4, GPS actual measurement data yt (a state in which a noise component is added) is input to the parameter K, and the output data of the parameter K and the estimated value ax (t / t-1) output from the parameter F are diverged. It shows a state where an estimated value ax (t / t) obtained by adding together for prevention is input to the parameter Z- ¹ . Although the parameter Z ^-1 estimates ax (t-1 / t- 1) is output to the position coordinate calculation unit 15, the branch output are input to the parameter F. The estimated value ax (t / t-1) output from the parameter F is fed back to the input stage of the parameter K as a future estimated value by the parameter H.
[0024]
In the filter unit 14 configured as described above, the covariance of the error value based on the past estimated value and the current value is “P (t / t−1)”, and n × determined by the number of GPS satellites to be observed n (n is a natural number of 1 or more: usually 4) If the matrix is “R”,
The optimum parameter K for enabling the error value to converge can be obtained from the following equation.
K = P (t / t- 1) · H T · [H · P (t / t-1) · H T + R] -1
[0025]
Further, the estimated value ax (t / t) can be obtained by adding the estimated error covariance corrected based on the current value of the GPS actual measurement data to the previously obtained estimated value (past estimated value). That is, it is calculated by the following formula.
ax (t / t) = ax (t / t-1) + K | yt-H.ax (t / t-1) |
[0026]
The covariance P (t / t) can be corrected by subtracting the covariance value obtained based on the information obtained this time from the previously calculated estimated covariance error. That is, it is calculated by the following formula.
P (t / t) = P (t / t-1) -K.H.P (t / t-1)
[0027]
Further, the future estimated value ax (t + 1 / t) and the estimated covariance error P (t + 1 / t) can be obtained as follows.
The future estimated value ax (t + 1 / t) can be obtained by calculating F · x (t / t), that is, by correcting the current value using the estimated value transition parameter obtained up to the previous time.
The estimated covariance error P (t + 1 / t) can be obtained by adding the obtained change in covariance and the change in non-indefinite value Q. That is, it can be obtained by the following equation using G as a new parameter (matrix).
P (t + 1 / t) = F · P (t / t) · F T + G · Q · G T
By repeating the above processing, the value of the estimation error covariance can be made as close to zero as possible.
[0028]
Returning to FIG. 3, the position coordinate calculation unit 15 calculates the three-dimensional position coordinates of the positioning point. The calculation of the three-dimensional position coordinates is performed in at least two scenes.
One scene is a scene in which position coordinates are calculated by single positioning, and the other is a scene in which position coordinates are calculated by carrier wave positioning.
The calculation of position coordinates by independent positioning is performed by filtering with the filter unit 14 as described above, and calculating the three-dimensional position coordinates (x, y, z) based on the estimated value when the specified error covariance converges. It is processing to do. Since the filter unit 14 calculates the estimated value in the direction in which the error is converged as described above, the time until the error converges is remarkably shortened as compared with the conventional method in which the estimated value is obtained by the FLOAT solution. . The position coordinates are stored in the positioning reference information storage unit 17 through the positioning reference information management unit 16 as positioning reference information representing the position of the virtual base station.
Even after the positioning reference information has been generated, for example, if the positioning point is changed significantly or the error becomes large, the measurement is re-measured according to the above procedure, and is obtained as a result. The already stored positioning reference information is updated based on the positioning result. When positioning is performed continuously, efficient positioning is possible by performing positioning at a new positioning point based on the difference value from the positioning reference information already stored.
[0029]
In carrier positioning, an integer value bias is obtained using the properties of radio waves. The integer value bias is the number of integer parts of the carrier wavelength at the start of signal reception + α (the portion of the above phase angle), and the integer value bias is a constant value as long as it continues to receive carriers from the same combination of GPS satellites. Become. This is because if the distance from one GPS satellite becomes +, the distance from the other GPS satellite becomes-. Focusing on this point, in this embodiment, the number of integer parts is obtained by calculating the distance from the GPS satellite and the frequency of the carrier wave, or by counting the number of carrier waves. Refine to. Then, as shown in FIG. 5, the error of the positioning reference information is further reduced from the phase angle representing + α. As a result, the final error is several centimeters.
[0030]
<Operation>
Next, the operation of the autonomous navigation apparatus according to this embodiment will be described with reference to FIGS. The operation of this autonomous navigation apparatus is roughly divided into a stage for generating and storing positioning reference information which is position information of a virtual reference station by independent positioning, and a stage for performing carrier positioning based on this positioning reference information.
[0031]
When performing independent positioning, as shown in FIG. 6, first, four optimal GPS satellites are selected by the GPS receiver 20 (step S101), and the L1 band (1.5 GHz) and the L2 band (1.2 GHz) 2 are selected. These GPS satellites are observed using two frequencies (step S102). The number of GPS satellites is the lowest unit for which simultaneous equations are established for unknowns. Note that inaccurate information is not used, that is, only GPS satellites that provide optimal information are selected.
[0032]
The positioning device 10 compares the data of each frequency, removes the noise component that is commonly included in the data, and generates one GPS actual measurement data from the two types of data (step S103). Then, by using the past, present and future estimated values as parameters, the positioning error based on the GPS actual measurement data is converged to within one wavelength of the carrier wave to obtain the positioning reference information (step S104).
[0033]
FIG. 7A shows the relationship between the virtual reference station and the positioning reference information. In the figure, the circle represents the error range. If the two match completely, there is no error, but this is not possible due to various factors. Therefore, a method for optimizing the filtering result is established. Since the filtering of this embodiment is a method of positively converging the positioning error based on the past estimated value, it takes about several minutes for the positioning error to reach within one wavelength. Note that there is no conventional idea of filtering the information obtained by actual measurement.
[0034]
In order to use the positioning reference information as the position information of the virtual reference station, the positioning device 10 stores the positioning reference information in the positioning reference information storage unit 17 (step S105). Then, an integer value bias is calculated using this positioning reference information (step S106), and a phase angle within one wavelength is detected. Carrier wave positioning is performed based on the detection result (step S107), and the position of the positioning point is determined (step S108). If necessary, the positioning result is selected as new positioning reference information, and the positioning reference information storage unit 17 is updated.
[0035]
FIG. 7B shows that by performing carrier wave positioning, the error of the positioning reference information is further reduced, and even if it is the maximum error, it falls within the error as the virtual reference station. In this state where the error is small, the virtual reference station itself does not fluctuate even when the autonomous navigation device moves as shown in FIG. 7C, so that stable positioning is possible.
The positioning method as described above will be described in comparison with the conventional RTK method as follows. FIG. 8A shows a conventional RTK system, and FIG. 8B shows an overview of the positioning system of this embodiment.
[0036]
In the conventional RTK method, as shown in FIG. 8 (a), after measuring the approximate position of the positioning point, the position of the positioning point is estimated based on additional information (distance, time, etc.) from the reference station. Calculate the ambiguity (provisional integer bias). There are seven unknown parameters: position information (x, y, z) of the GPS receiver and ambiguity (integer value bias) of the four GPS satellites. Therefore, the FLOAT solution has to be used and takes a lot of time. After estimating the position of the positioning point, the true integer bias is calculated. At that time, the temporary ambiguity is recalculated based on the additional information from the base station. There are three unknown parameters for carrier wave positioning based on additional information from the reference station: receiver position information (x, y, z). Thereafter, the position of the positioning point is determined by the FIX solution.
[0037]
On the other hand, in the positioning method of this embodiment, the optimal four GPS satellites are selected, and the positioning reference information (virtual reference station position information) is obtained by filtering to converge the two-frequency observation and the estimation error covariance of the observation result. Since the estimation is performed, the positioning reference information can be stored in the apparatus only by performing measurement for several minutes at the longest.
Since the positioning reference information is obtained almost accurately, the calculation of the integer value bias, that is, the process of calculating the true ambiguity based on the positioning reference information is quickly performed. Carrier wave positioning based on the positioning reference information is performed to further correct the error. At this time, there are three unknown parameters: position information (x, y, z) of the GPS receiver. Thereafter, the position of the positioning point is determined by the FIX solution.
When movement amount data is input from the movement amount data input unit 12, the position coordinates (x, y, z) of the moved positioning point are calculated based on the movement amount data and the positioning reference information.
[0038]
Thus, in the autonomous navigation device of the present embodiment, it is possible to perform highly accurate carrier wave positioning in almost real time without using a reference station, so positioning in a mountain area where the reference station is not installed, positioning by a ship at sea, Positioning of undeveloped areas where there are no base stations, and positioning of airplanes during takeoff and landing where the use of radio waves is suppressed are also possible. Further, since it is not necessary to receive the reference station, the cost of the autonomous navigation device itself can be reduced.
[0039]
In the present embodiment, an example in which the positioning device 10 and the GPS receiver 20 are separated has been described, but both may be integrated.
In addition, a GPS receiving mechanism is added to a PDA (Personal Digital (Data) Assistants) equipped with a memory and a processor, and the computer program of the present invention is loaded into the memory and executed by the processor. Autonomous positioning methods can also be implemented.
[0040]
【The invention's effect】
As is clear from the above description, according to the present invention, it is possible to perform high-precision and real-time positioning using existing GPS satellites and GPS receivers. In addition, since a positioning algorithm can be realized by a computer, it becomes possible to flexibly cope with further optimization by improving the algorithm and adding parameters.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of a use state of an autonomous navigation device to which the present invention is applied.
FIG. 2 is a configuration diagram of a GPS receiver.
FIG. 3 is a functional block diagram of a positioning device.
FIG. 4 is a parameter configuration diagram of a filter unit of the positioning device.
FIG. 5 is a diagram illustrating the principle of a carrier positioning method according to an embodiment of the present invention.
FIG. 6 is an explanatory diagram of a positioning procedure according to an embodiment of the present invention.
FIGS. 7A to 7C are conceptual explanatory diagrams of a positioning method of the present invention.
FIG. 8 is a comparative explanatory diagram of a conventional positioning method and the positioning method of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Positioning apparatus 11 GPS data input part 12 Movement amount data input part 13 Noise removal part 14 Filter part 15 Position coordinate calculation part 16 Positioning reference information management part 17 Positioning reference information storage part 18 Display image generation part 19 Output control part 20 GPS reception Machine 21 GPS antenna 22 Movement detection sensor 23 Data receiving circuit 24 Interface circuit DD Storage device PR Printer DP Display GS1 to GS6 GPS satellite

Claims (9)

An autonomous positioning method performed by one autonomous navigation device having a GPS receiver and a memory ,
Save the autonomous navigation device placed in the positioning point, a plurality of GPS satellites to acquire the one of the GPS measurement data and observed by the GPS receiver, to estimate the current and past GPS measurement data acquired repeated calculation of future estimates based on the has been that value until the estimation error covariance by the estimated value converges within a predetermined value, the estimated value of the time of the convergence as the positioning reference information representative of the position of the virtual reference station Saving to memory,
The autonomous navigation device has a step of performing carrier wave positioning at the positioning point with reference to positioning standard information stored in the memory,
Autonomous positioning method by GPS. The autonomous navigation device detects a combination of four GPS satellites that minimize the positioning error due to the current value, and observes and compares each of the detected four GPS satellites at two different frequencies with the GPS receiver. In this way , it is characterized in that one GPS actual measurement data obtained by deleting a noise component common to each frequency is obtained.
The autonomous positioning method according to claim 1. The predetermined value is a value within one wavelength of a carrier wave transmitted by a GPS satellite to be observed,
The autonomous positioning method according to claim 1. The said autonomous navigation device, processing to calculate on the basis of parameters to allow the convergence of error values in the estimated error covariance by value estimated to said current value and the past, the current value, the estimated value previously obtained processing for calculating by adding the estimated error covariance that corrected based on the current value, the error covariance, processing for correcting by subtracting the value of the covariance by the current value from the estimated covariance error previously determined, estimated future processing to calculate the value, the processing for calculating by modifying using the parameter estimates transition of obtaining the current value up to the previous, the estimated covariance error, by adding the change in the transitions and undefined values of the covariance By repeatedly executing, the value of the estimated error covariance is converged,
The autonomous positioning method according to claim 1. The autonomous navigation device records the positioning result by the carrier positioning when the positioning point moves in the memory as new positioning reference information,
The autonomous positioning method according to claim 1. In the carrier positioning, distances to the plurality of GPS satellites starting from a virtual position specified by the positioning reference information stored in the memory are respectively determined as carrier frequency from each GPS satellite and transmission time of the carrier. An integer value bias is calculated by dividing the calculated distance by the frequency of the carrier wave, and a phase angle within one wavelength of the carrier wave is calculated from the integer value bias. Based on the length represented by the corner, the position of the positioning point is specified,
The autonomous positioning method according to claim 1. Input means for inputting signals of two types of frequencies received by a GPS receiver capable of observing each of a plurality of GPS satellites at two types of frequencies;
Preprocessing means for obtaining one GPS actual measurement data by deleting a noise component common to each frequency from these inputted signals;
In addition to acquiring GPS actual measurement data obtained by this pre-processing means, the estimated error is calculated based on the current value of the acquired GPS actual measurement data and the value estimated and stored in the past. It repeats until the covariance converges within a predetermined value, and the positioning reference information generating means for storing the estimated value obtained thereby as positioning reference information in a predetermined memory
Carrier positioning means for performing carrier positioning with reference to positioning standard information stored in the memory,
Autonomous navigation device. The positioning reference information determining means includes a filter unit for minimizing an estimation error covariance, and is configured to calculate the future estimated value by the filter unit.
The autonomous navigation apparatus according to claim 7. A computer that can be connected to a GPS receiver capable of observing each of a plurality of GPS satellites at two frequencies.
Preprocessing means for inputting signals of two types of frequencies received by the GPS receiver, and deleting noise components common to each frequency from these input signals to obtain one GPS actual measurement data ,
While acquiring the GPS actual measurement data obtained by this pre-processing means, the calculation of the future estimated value based on the current value of the acquired GPS actual measurement data and the value estimated and stored in the past , repeated until the difference in converges to a predetermined value, the positioning reference information determining means to store in a predetermined memory estimates Thereby obtained as the positioning reference information,
The order to function as a carrier positioning means for performing a carrier positioning that the reference information positioning reference information stored in the memory, the computer program.

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