JPS6238378A - Navigation device - Google Patents

Abstract

PURPOSE:To transmit at least the longitude and latitude of a car among pieces of three-dimensional position information and to receive position information on another vehicle, and to know its position by using radio equipment capable of transmitting and receiving signals to and from a global positioning system receiver. CONSTITUTION:Transmission signals of GPS (global positioning system) satellites 1-4 are received by an antenna 5 and the GPS receiver 6 performs frequency reverse spreading and demodulation to find the position of a user. A map corresponding to the position is read out of a map information recording device 10 and displayed 9, and the position of the user is indicated with a marker. Further, position information (longitude, latitude, and altitude) is transmitted by the radio equipment 8 when necessary. A transmission radio wave from another user of this navigation device is received and the position of the user is also displayed 9.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a navigation device using a global positioning system (hereinafter referred to as GPS).

[Technical background of the invention and its problems GoGPS is a new global satellite navigation system being developed by the U.S. Department of Defense. The three-dimensional altitude position can be determined with an accuracy of several tens of meters.

The satellites have a circular orbit with an orbital inclination of 5 da from the equator and an altitude of approximately 20,000 km, with three satellites arranged on each of six orbital planes.
It consists of a total of 21 satellites: 8 satellites and 3 spare satellites.

Four or more satellites are always visible anywhere on Earth.

The principle by which a user's three-dimensional position is determined using GPS will be explained below. As shown in FIG. 3, the GPS magician has an accurate clock and transmits the location information and time of the magician itself. A user has a clock that is less accurate than the clock mounted on the satellite and is not synchronized with the satellite's clock, and uses this clock to detect the satellite's transmission at time t, for example. *Receive the location information in 3.4) and find the user's time tui at that time. This tu,
The distance R1 between satellite i and the user is calculated from [. Since this R1 includes the user's clock error Δtu, it is called a pseudo distance. Therefore, the distance between the true user and the satellite ■ is R,
Then, equation (1) holds true.

C(tu4-t5)=几i=”i+ΔtuC・・・・・・
・・・・・・・・・・・・・・・ (1) However, C is the speed of light and i is 1, 2, 3, 4.

In this equation, the difference Δtu between the latitude, longitude, and altitude of the user and the clock is unknown. Since there are four unknowns, if we calculate the above pseudorange Ri for the four satellites, fi1
The three-dimensional position of the user can be determined from the formula.

A GPS receiver that receives radio waves from GPS satellites is mounted on a moving object such as a car, and the current position is calculated moment by moment.
A navigation device that indicates this with a mark on a map displayed on a screen has been devised and prototyped. Map information is stored on optical discs or compact discs (CDs), allowing users to freely zoom in on a wide range, and even calculate and display the optimal route for the vehicle to its destination. However, in this case, the location of each car equipped with a navigation device is displayed individually, so multiple cars that are far apart must communicate with each other via voice radio, etc. in order to know the location of other cars. There was only one.

[Purpose of the invention]

The present invention has been made in view of the above points, and an object of the present invention is to provide a navigation device for a vehicle using GPS that can automatically transmit calculated current position information wirelessly.

[Summary of the invention]

The present invention is an automobile navigation device using GPS, which transmits at least the latitude, longitude, and altitude of three-dimensional position information of the own military by radio waves using a wireless device capable of transmitting and receiving data to and from a GPS receiver; Receive location information of other vehicles,
The feature is that it can also know the location of other cars.

〔Effect of the invention〕

According to this invention, it is possible to obtain high-precision position information for both own and other vehicles, and when driving with multiple cars, it is possible to clearly see and enjoy the mutual positional relationship, and it is also useful for preventing danger. If radio equipment and display devices are installed at the station, it will be very effective for vehicle management and dispatch.

Furthermore, the overall cost can be reduced by using a personal radio, which is widely used in cars, as the radio. In addition, if a GPS receiver is installed at the base station and the location information is transmitted to moving cars, etc., the base station is fixed and the location is known with high precision, so the error can be offset and the location accuracy can be improved. can be improved.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. The present invention comprises an antenna 5, a GPS receiver 6, a radio 8 capable of transmitting and receiving, an antenna 7, a map recording device 10, and a display device 9.

GPS satellites have an orbital inclination of 55° with respect to the equator and an altitude of 20°.
．． It has a circular orbit of 187km and consists of 18 orbitals, three each placed in six orbits. Four or more satellites are placed so that they can be seen 24 hours a day anywhere on Earth.

GPS satellites 1, 2. The transmitted signal 4 of j, 4 is received by the antenna 5, and the frequency is despread and demodulated by the GPS receiver 6 (
1) Find the user's position by solving the equation given by Eq.

A map corresponding to the above position is read out from the device 10 that records map information, the map is displayed on the display device 9, and the user's position is also displayed with a marker. Furthermore, this positional information (degree of latitude, longitude, altitude) can be transmitted via the radio 6 if necessary. In this example, a personal radio that is commonly used in automobiles is used as the radio. Further, it is possible to receive radio waves transmitted by users of other navigation devices according to the present invention, and to display the positions of other users on the display device 9.
□It is. FIG. 4 shows an example in which the positions of four cars, including those of other users, are each displayed by markers. In this way, when you go on a road trip with multiple cars, you can clearly see the relative positions of each other, so you won't get lost, and the fun will be doubled.

FIG. 5 shows an application example of the present invention, in which a radio device 11, a map recording device 13, and a display device 14 are combined, and position information transmitted from a user of the navigation device of the present invention can be displayed on a map. It is very effective for vehicle management and dispatch for transportation companies, taxi companies, etc.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a block diagram showing a conventional example, FIG. 3 is a diagram showing the principle of GPS, and FIG. 4 is a diagram showing a display example of the present invention. FIG. 5 is a block diagram showing a modification of the present invention. 1.2.3.4...GPS satellite, 5,7,11゜15
...Antenna, 6,16...GPS receiver, 8゜1
2...Radio device, 9,14,18.19...Display device, 10.13,17...Map recording device, 20...Road, 21...Navigation device user of the present invention, 22 ,23.2
4...Other users. Agent Patent Attorney Ken Nori Chika Kikuo Takehana Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

Claims (3)

[Claims] (1) Equipped with a GPS receiver and a wireless device capable of transmitting and receiving,
A navigation device characterized in that the wireless device radiates position information obtained by a GPS receiver into the air as radio waves. (2) The navigation device according to claim 1, wherein a personal radio device is used as the radio device. (3) A device according to claim 1, comprising a device that records map information and a device that displays a map, and displays the positions of a plurality of GPS users on the map display device. navigation equipment.