JPS6326529A - Altitude correction system for gps receiver - Google Patents

Abstract

PURPOSE:To correct altitude information automatically and to obtain high-accuracy altitude information by judging the difference between altitude information at the time of three-dimensional position measurement and altitude information sent from an altimeter as the error of the altimeter. CONSTITUTION:A GPS navigation device consists of the altimeter 1 and a GPS receiver 2 and the altimeter 1 sends the altitude information to the receiver 2 steadily. Then, when the three-dimensional position measuring operation is performed, the signal of a satellite is received by an antenna 21, a reception part 22 demodulates navigation data and measures artificial distance, and an arithmetic part 23 accurately calculates the position of a user consisting of longitude, latitude, and altitude on the basis of the navigation data and artifical distance. For the purpose, the altitude measured at the time of the three-dimensional position measurement is compared with the altitude measured by the altimeter 1 by an altitude correction arithmetic part 24 and their difference indicates the difference between the measured value of the altitude 1 and the real altitude, i.e. the error of the altimeter 1. Thus, the value obtained by adding the difference as a correcting value to the altitude information from the altimeter 1 is used as new altitude information, so the position is measured with high accuracy.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a GPS receiver that is capable of two-dimensional positioning and three-dimensional positioning, and that uses altitude information from an altimeter as altitude information when performing two-dimensional positioning. This invention relates to an altitude correction method for correcting altitude errors during two-dimensional positioning.

[Prior art]

When performing two-dimensional positioning using satellites in a GPS receiver, altitude information must be provided. conventional GP
In the S receiver, as a means for obtaining altitude information, altitude information from an altimeter is input into a GPS receiver to perform two-dimensional positioning.

[Problem that the invention seeks to solve]

However, in the positioning method that obtains altitude information from an altimeter as described above, the error between the altitude input from the altimeter and the actual altitude deteriorates the positioning accuracy, and in order to perform more accurate positioning, it is necessary to It was necessary to input altitude information into the GPS receiver. For example, when using a barometric altimeter as an altimeter, the measured altitude varies depending on changes in atmospheric pressure, so there is the inconvenience of having to calibrate the measured altitude at a known altitude. In conventional machines, this calibration is a cumbersome and manual process.

The present invention has been made in view of the above points, and provides an altitude GPS receiver that eliminates the above problems, can automatically calibrate altitude information from an altimeter, and can obtain highly accurate altitude information. The purpose of the present invention is to provide a correction method.

[Means for solving problems]

In order to solve the above problems, the present invention provides altitude information calculated by a calculation unit during three-dimensional positioning in a GPS receiver that captures altitude information from an altimeter during two-dimensional positioning and performs positioning using the altitude information. is the true value, the altitude information calculated by the calculation unit and the altitude information from the altimeter are compared in the altitude correction calculation unit, the difference is determined to be the altitude error of the altitude liver, and the altitude error is retained, The altitude error is added as a correction value to the altitude information from the altimeter during two-dimensional positioning, and the added value is used as the altitude information.

[Effect]

With the above configuration, the difference between the altitude information during three-dimensional positioning by a satellite and the altitude information sent from the altimeter is determined to be an error in the altimeter, and the difference between the altitude information from the altimeter during two-dimensional positioning is determined as an altimeter error. Since the value taken into account as a correction value is used as new altitude information, highly accurate position measurement can be performed during two-dimensional positioning without being affected by the measurement error of the altimeter.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on the drawings.

The figure is a block diagram showing the system configuration of a GPS navigation device to which the GPS receiver altitude correction method according to the present invention is applied. The GPS navigation device has altimeter 1 and GP as shown in the figure.
It is composed of an S receiver 2. Altitude information is regularly sent from the altimeter 1 to the GPS receiver 2.

The GPS receiver 2 includes an antenna 21 , a receiving section 22 , a calculation section 23 , an altitude correction calculation section 24 , and a display section 25 . A radio signal from a satellite is received by the antenna 21, and the signal is sent to the receiving section 22. In the receiving section 22, each satellite -
Measurement of pseudo distances between user positions and demodulation of navigation data from the satellite are performed, and the pseudo distances and navigation data are sent to the calculation unit 23. In the calculation section 23, the reception section 22
Positioning calculations are performed based on information from.

In the case of two-dimensional positioning, the user's longitude, latitude, and altitude can be measured by obtaining altitude information from the altitude correction calculation unit 24. The measured position obtained by the calculation section 23 is sent to the display section 25 and can be displayed.

During three-dimensional positioning, altitude information h+ obtained as a result of positioning calculation by the calculation unit 23 is sent to the altitude correction calculation unit 24.

The altitude correction calculation unit 24 determines the altitude information obtained by this three-dimensional positioning as the true value, compares it with the altitude information from the altimeter 1, and holds this altitude error as the altitude error of the altimeter 1. do.

During two-dimensional positioning, the altitude correction calculation unit 24 adds the altitude error value held above to the measured altitude information from the altimeter 1 as a correction value, and uses the adjusted value as the true altitude information. Send to 23rd. The calculation unit 23 performs positioning calculations using the altitude information to determine the user's position.

In the positioning of the GPS navigation device with the above configuration, three-dimensional positioning is performed by receiving signals from four satellites using the antenna 21, demodulating the navigation data and measuring pseudo distances using the receiver 22,
Based on the navigation data and the pseudo distance, the calculation unit 23 accurately calculates the user's position in terms of longitude, latitude, and altitude.

Follower, altitude and altimeter 1 that can be measured during this 3D positioning
The difference from the altitude measured at 2 indicates the difference between the measured value of altimeter 1 and the true altitude, that is, the error of altimeter 1.
The above method uses a value obtained by adding this difference as a correction value to the altitude information from the altimeter 1 during dimensional positioning as new altitude information, and performs highly accurate positioning without being affected by the measurement error of the altimeter 1. be able to.

〔Effect of the invention〕

As explained above, according to the present invention, the difference between the altitude information during three-dimensional positioning and the altitude information sent from the altitude needle is determined to be an error in the altimeter, and the difference between the altitude information sent from the altimeter during two-dimensional positioning is Since the value taken into account the above error as a correction value is used as new altitude information, it is possible to perform highly accurate position measurement without being affected by the measurement error of the altimeter during two-dimensional positioning, and the above processing can be performed automatically. Since the calibration is performed at a location where the altitude is known, an excellent effect can be obtained in that the inconvenient work of having to calibrate the altitude measured by the altimeter at a known altitude location is eliminated.

[Brief explanation of drawings]

The figure is a block diagram showing the system configuration of a GPS navigation device to which the GPS receiver altitude correction method according to the present invention is applied. In the diagram, 1...altimeter, 2...GPS receiver, 2
1...Antenna, 22...Receiving section, 2°3...
...Calculation unit, 24...Altitude correction calculation unit, 25...
・Display section.

Claims (1)

[Claims] Altitude information calculated by a calculation unit during 3D positioning in a GPS receiver that is capable of 2D positioning and 3D positioning, captures altitude information from an altimeter during 2D positioning, and performs positioning using the altitude information. As the true value, the altitude information calculated by the calculation unit and the altitude information from the altimeter are compared in the altitude correction calculation unit, the difference is determined to be the altitude error of the altimeter, and the altitude error is retained. An altitude correction method for a GPS receiver, characterized in that the value held as the altitude error is added to the altitude information from the altimeter during two-dimensional positioning, and the added value is used as the altitude information.