JPH0915315A - Method for indicating global positioning system satellite - Google Patents

Abstract

PROBLEM TO BE SOLVED: To intuitively understand an obstruction interrupting radio wave by detecting the position of a satellite which can be received or cannot be received and indicating it in such a manner that it may be discriminating easily. SOLUTION: An advancing-direction operation part 12 detects the radio wave doppler shift of every satellite from the output signals of a GPS reception part 11 which receives radio waves of every satellite through an antenna 10 and it operates the advancing direction P of a mobile body, then it sends the direction to an indication control part 14. In addition, a satellite information detection part 13 detects the position and reception status of a satellite which can be received, according to the output signal 11. The control part 14 finds relative angles between the positions P and respective satellites in order to prepare a newly corrected data for indication. The indication part 15 draws the sky position of the respective satellites by using the data and indicates it together with the reception status. Then, in case where there is no satellite that can be received, the value just before the reception level becomes lower among the results that the detection part 13 stores every time is adopted so as to find out the position of a satellite which cannot be received and draw it. At this time, it is indicated by different colors, etc., so that it may be easily discriminated, thereby understanding intuitively an abstruction interrupting the radio wave from the satellite.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a global positioning system satellite display method in which radio waves from respective satellites are received by a receiver to position the position of a mobile body.

[0002]

2. Description of the Related Art The global positioning system, so-called GPS, is a satellite-based positioning system that covers the entire globe. GPS uses the position of the user's own position from the surface of the earth as the base of the pyramid to form the constellation of satellites that form a constellation for the user on an orbit at an altitude of 20183 km. It is a system to obtain as the apex. 2 GPS satellites, including spares
One orbits an orbit around the earth.
As described above, the positioning by GPS is performed by G that forms the bottom of the pyramid.
The number of PS satellites received is a necessary condition for establishing positioning.

[0003] In order to determine whether or not the reception conditions satisfy the required conditions for positioning, a conventional method is to display on the screen GPS satellites that orbit the sky. A display based on this method is shown in FIG.

When the celestial sphere is projected onto a two-dimensional plane such as the ground, the position of the GPS satellite can be displayed in two-dimensional coordinates. By this projection, the whole sphere is represented by a circle,
The circle 20 shown in FIG. 5 indicates the horizon. In addition, the intersection of the lines indicating north, south, east, and west, that is, the center point M of the circle 20
Indicates the position of an object that receives radio waves from GPS satellites, for example, the position of a moving body. Thus, when the position of the GPS satellite is displayed two-dimensionally, the position of the GPS satellite can be represented by the relationship between the azimuth angle φ and the elevation angle θ. Circle 20 shown in FIG.
The center point M of the circle 20 is set to an elevation angle θ = 90 °, and the elevation angle decreases concentrically in the radial direction so that the elevation angle θ = 0 ° on the circumference of the circle 20.

Conventionally, as shown in FIG. 5, the GPS satellite position display always displays true north at the 0 o'clock position of the clock on the display screen. The azimuth angle φ, which is another element in displaying the position of the GPS satellite, displays the azimuth of each GPS satellite on the screen with reference to true north. For example, the azimuth angle φ of the east in the clockwise direction is φ = 90 °.

When a GPS receiver for receiving radio waves from such GPS satellites is mounted on a mobile unit, the traveling direction of the mobile unit is displayed on this display screen using various display methods. The display screen of FIG. 5 shows that the moving body is moving in the direction of arrow P.

[0007]

By the way, when a GPS receiver is mounted on a mobile unit and receives radio waves from GPS satellites, radio waves may be blocked by obstacles such as high-rise buildings. For this reason, the number of GPS satellites received is reduced, which often results in improper positioning. Therefore, if the azimuth angle and the elevation angle of the GPS satellite whose radio wave is blocked by the obstacle can be known, the obstacle that causes the radio wave can be identified. By moving the moving body so as to avoid this obstacle, it is possible to secure the number of GPS satellites received and enable positioning by GPS satellites.

However, if only the GPS satellites that can be received at present are displayed, it is difficult to identify the obstacle because it is necessary to check the memory to confirm which satellite has become unreceivable due to an obstacle. However, there is a drawback that it is difficult to take measures such as moving to avoid obstacles.

Here, when displaying unreceivable satellites at the same time as receivable satellites, it is desirable that they can be easily distinguished.

The present invention has been made in view of the above situation, and detects not only receivable satellites but also unreceivable satellites and displays them in a readily discriminable manner to provide GPS satellites. Obstacles that block the radio waves from
Alternatively, a global positioning system satellite (GPS) that can intuitively understand the direction of an obstacle
(Satellite) display method is intended to be provided.

[0011]

A method of displaying a global positioning system satellite according to the present invention is a method of displaying a satellite of a global positioning system that receives radio waves from each satellite. A step of detecting the position information of the receivable satellites, a step of detecting the position information of the unreceivable satellites after detecting the position information of the receivable satellites, and a discrimination of these receivable satellites and unreceivable satellites The above-mentioned problem is solved by having a step of displaying possible.

As the position information of the unreceivable satellite, it is possible to use the position information immediately before the reception level of the receivable satellite becomes small and the satellite becomes unreceivable. In particular,
Each time it detects the satellite that can be received, it is stored in the memory,
The position information immediately before the reception level of the receivable satellite becomes so small that it cannot be detected may be used as the position information of the unreceivable satellite.

In addition, it is preferable that the display color of the receivable satellite and the display color of the unreceivable satellite are different from each other.

According to the satellite display method of the global positioning system of the present invention, the position information of unreceivable satellites is obtained after detecting the position information of receivable satellites among the satellites. At this time, the position information immediately before the previously detected receivable satellites become undetectable due to the low reception level is used as the position information of undetectable satellites, and these receivable satellites and unreceivable satellites are used. And are displayed in a distinguishable manner by using different colors.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a method for detecting a global positioning system satellite (GPS satellite) according to the present invention will be described below with reference to the drawings.

A global positioning system (GPS) receiver to which the embodiment of the present invention is applied will be described with reference to the schematic functional block configuration shown in FIG. The GPS (Global Positioning System) receiver shown in FIG. 1 is an example in which it is mounted on a moving body for use.

The GPS receiving apparatus shown in FIG. 1 includes a GPS receiving section 11 which receives radio waves from each GPS satellite via an antenna 10 and extracts information from the radio waves, and a GPS receiving section 1
1. A traveling direction calculation function unit 12 that calculates the traveling direction of the moving body based on the output signal from the mobile unit 1, and a satellite information detection function unit 13 that detects the position and reception status of each GPS satellite based on the output signal from the GPS reception unit 11. And the traveling direction calculation function unit 1
2 and a display control function unit 14 that controls display based on signals supplied from the satellite information detection function unit 13 and a display function unit 1 that displays an output signal from the display control function unit 14.
5 is provided.

Here, the procedure for controlling the display by the GPS receiving apparatus of FIG. 1 including an example of the embodiment of the GPS satellite display method according to the present invention will be described with reference to the flow chart shown in FIG. Further, a display screen of the position of the GPS satellite in the sky by this display control is shown in FIG. In these descriptions, FIG. 1 will be referred to as necessary.

The GPS receiver starts displaying the position in the sky of the GPS satellite received by the GPS receiver 11 via the antenna 10 and proceeds to step S10.

In step S10, an output signal corresponding to the received radio wave is supplied to the traveling direction calculation function unit 12 shown in FIG. The traveling direction calculation function unit 12 detects the Doppler shift of the radio wave from each satellite based on the output signal, calculates the traveling direction of the moving body, and proceeds to step S11. This traveling direction P is calculated as a deviation ΔNP of the azimuth angle, for example, in the clockwise direction from the reference true north N. The value of the deviation ΔNP of the azimuth angle is sent to the display control function unit 14.

In step S11, the azimuth angle φ and the elevation angle θ of the receivable GPS satellites are obtained. The azimuth angle φ and the elevation angle θ of this GPS satellite are detected by the satellite information detecting function unit 13 shown in FIG. The azimuth angles of the four satellites shown in FIG. 3 are rotated clockwise with reference to true north and the azimuth angles φ = R _{1 to} R ₄
Are calculated respectively. In addition, the elevation angle θ from the horizon is also obtained and the process proceeds to step S12.

In step S12, the traveling direction P and each GP
(| R−ΔNP |, θ) is obtained as a new azimuth angle φ ′ as the relative angle of the S satellite, and the traveling direction is set to the 0 o'clock direction of the clock and used as the data for displaying the GPS satellite. This data becomes correction data for the data of the azimuth angle φ and the elevation angle θ obtained in step 11. The satellite information detection function unit 13 shown in FIG. 1 supplies the display control function unit 14 with data regarding the position display of each detected GPS satellite. Therefore, in the display control function unit 14, for example, the GPS shown in FIG.
New correction data the difference in azimuth ΔNP in the traveling direction from the azimuth angle R ₄ satellites _{S 4 (φ 4 ', θ} 4) = (R 4 -ΔNP,
θ ₄ ) and proceed to step S13.

In step S13, the above step S12 is performed.
The position in the sky of the GPS satellite received using the correction data obtained in step 1 is drawn on the display function unit 15 shown in FIG.
After this drawing, the process proceeds to step S14.

In step S14, it is detected whether or not there is a receivable GPS satellite other than the drawn GPS satellite. If there are other GPS satellites that can be received (Ye
If s), the process returns to step S11. If there are no other GPS satellites that can be received (No), step S15.
Proceed to. Whether or not the GPS satellite can be received is determined by the satellite information detection function unit 13 shown in FIG. 1 based on the level of the received radio wave, for example, the reception status of each GPS satellite.

In step S15, G
The azimuth angle φ and elevation angle θ of the PS satellite are obtained. As for the position information of the GPS satellite when receivable, for example, the azimuth angle φ and the elevation angle θ are stored in the memory each time they are detected. GP which became unreceivable by using the value immediately before this reception level becomes small
After obtaining the azimuth angle φ and the elevation angle θ of the S satellite, the process proceeds to step S16.

In step S16, the relative angle of the unreceivable GPS satellite with respect to the traveling direction P is calculated based on the value obtained in step S15, as described above. Correction data for GPS satellites that cannot be received is obtained based on the calculated angle. The calculation of the correction data when reception is impossible is also obtained by the display control function unit 14 shown in FIG.
Proceed to 17.

In step S17, the above step S15 is performed.
The position of the unreceivable GPS satellite in the sky is drawn on the display function unit 15 shown in FIG. At this time, the display of the reception status is displayed so as to be integrated with the display of the arrangement of each satellite in the sky, and in order to distinguish the unreceivable satellites from the receivable GPS satellites, for example, different colors are set. Therefore, it can be easily identified. After this drawing, the process proceeds to step S18.

In step S18, it is detected whether or not there are GPS satellites that cannot be received other than the drawn GPS satellites. If there are other GPS satellites that cannot be received (Ye
If s), the process returns to step S15. If there are no other GPS satellites that cannot be received (No), all GPS satellites
This routine ends by ending the satellite position display. Similar to the case of step S14, whether or not the GPS satellite can be received is determined by the satellite information detection function unit 13 shown in FIG. 1 by the reception status of each GPS satellite, for example, by the level of the received radio wave.

A more specific example of displaying the sky position of the GPS satellite in this way is shown in FIG.

The display screen showing the sky position of the GPS satellite shown in FIG. 4 is displayed as one of the information about the GPS satellite. A droplet-shaped symbol 16 is displayed centering on the intersection of the lines indicating the north, south, east, and west directions. Here, the direction indicated by the pointed portion of the symbol 16 is the traveling direction P shown in FIG.
Is shown. Actually, the GPS satellites are indicated by hatching the receivable satellites, and the GPS satellites are shown by numbers. This hatching is, as described above, an illustration that different colors and the like are set so that they can be easily discriminated. The GPS satellites shown in FIG.
The satellites 0, 21, and 23 appear on the sky of the mobile unit and are receivable (Found). On the other hand, the 17th GPS satellite shown in FIG.
It is understood that it is in st).

Here, on the display screen, since the symbol 16 representing the moving body is displayed centering on the intersection of the lines indicating the north, south, east and west directions, the relationship between the direction from the moving body and the GPS satellites can be seen at a glance. Easy to check.

Further, it becomes easy to understand that the GPS satellite that cannot receive the signal may be unable to receive the signal due to, for example, an obstacle located right behind the moving body. In particular, in a moving body in which this GPS receiving device is downsized and mounted on a vehicle, the driver's traveling direction coincides with the traveling direction of a screen displaying the sky position of the GPS satellites. The position of the satellite can be intuitively recognized, and the vehicle can be easily moved to a position where the GPS satellite can be received.

Since it is necessary to secure the number of GPS satellites to be received when performing positioning in this way, it becomes easy to move the moving body so as to avoid the obstacle causing the radio wave interruption. It is possible to intuitively understand the obstacle blocking the radio wave from the device or the direction of the obstacle, and it is possible to escape the anxiety from the positioning impossible state.

[0034]

As is apparent from the above description, according to the global positioning system satellite display method of the present invention, there is provided a global positioning system satellite display method for receiving radio waves from each satellite. Of the satellites, a step of detecting position information of satellites capable of receiving signals, a step of detecting position information of unreceivable satellites after detecting the position information of the receivable satellites, By having a step of displaying satellites and unreceivable satellites in a distinguishable manner, the position information of unreceivable satellites can also be detected and displayed, and these receivable satellites and unreceivable satellites can be easily distinguished. , You can intuitively understand the direction of the obstacle.

Here, the position information of the unreceivable satellite can be easily and surely detected by using the position information immediately before the reception level of the receivable satellite becomes small and the satellite becomes unreceivable.

Further, since the display color of the receivable satellites and the display color of the unreceivable satellites are displayed differently on the display screen, it is possible to visually and easily and reliably detect the position and reception of each satellite. You can recognize the situation.

By displaying the position of each of the satellites detected in the sky and the reception status of these satellites in this manner, the receivable satellites and unreceivable satellites can be confirmed in the sky, and the user can confirm the position. Can intuitively understand the obstacle blocking the radio waves from the GPS satellites, or the direction of the obstacle, and can escape the anxiety from the positioning impossible state.

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic functional block configuration of a GPS receiving apparatus to which a GPS satellite display method according to an embodiment of the present invention is applied.

FIG. 2 is a schematic block diagram of the GP shown in FIG.
GPS that can receive and cannot receive by operating the S receiver
It is a flow chart explaining the procedure for displaying a satellite.

FIG. 3 is a schematic diagram illustrating a method of calculating a traveling direction and correction data with respect to a reference necessary for displaying GPS satellites.

FIG. 4 is a diagram showing an example of a more specific display screen that displays information regarding the position of a GPS satellite.

FIG. 5 is a diagram illustrating a method for displaying on the screen the position of a GPS satellite in the sky with a conventional GPS receiver.

[Explanation of Codes] 10 Antenna, 11 GPS Receiver, 12 Moving Direction Calculation Function of Mobile Object, 13 Satellite Information Detection Function, 14 Display Control Function, 15 Display Function

Claims (3)

[Claims] 1. A method of displaying a global positioning system satellite in a global positioning system receiver that receives radio waves from each satellite and measures the position of a mobile body, wherein the satellite is capable of receiving a signal from among the satellites. Detecting the position information of the unreceivable satellite after detecting the position information of the receivable satellite, and displaying the receivable satellite and the unreceivable satellite in a distinguishable manner. A method for displaying a global positioning system satellite, comprising: 2. The global positioning system satellite according to claim 1, wherein the position information of the unreceivable satellites is the position information immediately before the receivable satellites become unreceivable due to a low reception level. Display method. 3. The method for displaying a global positioning system satellite according to claim 1, wherein the display color of the receivable satellite and the display color of the unreceivable satellite are displayed differently.