JPH02234014A - Azimuth detecting device - Google Patents

Abstract

PURPOSE:To execute the detection with high accuracy by discriminating orbit informa tion by catching a signal from a satellite, deriving an angle of the satellite direction and the earth reference direction, deriving an angle of the satellite direction and a reference axis of a body to be detected, and adding and subtracting each angle. CONSTITUTION:A receiver 16 which receives GPS (global positioning system) signal from antennas 11, 12 derives a position to the earth of all GPS satellites and the own position of a body to be detected from each signal and sends them to an azimuth calculating part 17. Subsequently, the calculating part 17 decides in which direction and how many times a rotary base 13 is rotated, from satellite orbit information which is sent and a rotation angle of the antenna, gives a rotation driving signal for designating the direction and the rotation quantity, and the rotation angle to a rotation controller 18, and brings the rotary base 13 to rotation control to a target rotation angle. In this case, the antenna rotation angle becomes an azimuth of the GPS from a reference axis of the body to be detected. Therefore, by adding or subtracting the azimuth derived from the antenna rotation angle, and the azimuth of the satellite to the earth coordinate in the calculating part 17, the azimuth to the earth coordinate of the reference axis of the body to be detected is derived.

Description

[Detailed Description of the Invention] [Purpose of the Invention] (Field of Application for Sankojo) This invention is directed to the direction of movement used in moving objects such as vehicles, ships, and robots equipped with wireless communication equipment, and devices with rotating mechanisms. This invention relates to an angle detection device.

(Prior Art) Vehicles and the like equipped with wireless communication equipment and broadcasting equipment are required to be able to immediately and accurately detect the bearings of communication satellites, wireless stations, and targets. Furthermore, it is essential for other moving objects such as vehicles, ships, robots, and flying objects to know their own orientation. As an azimuth angle detection device for such uses, a magnetic compass is generally used in a simple manner, and a gyro compass is used when high accuracy is required.

However, since magnetic compasses measure the earth's magnetism, large errors can occur if there are magnetic materials or objects that generate magnetism in the surrounding area. For this reason, special casings and
Although the installation conditions have been made stricter, the current situation is that the effects of these efforts are extremely small.

On the other hand, orientation detection devices that apply gyros such as directional gyros have problems such as the high cost of the gyro and the difficulty of maintenance.In particular, when a gyro with a rotating body is used, the settling time is long and the operation is difficult. Sometimes there is also the problem of slow rise times. Furthermore, when a gyro is applied, it is not possible to detect one's own position except for INs (inertial navigation systems), which is very inconvenient.

In addition, all gyro-applied devices, including INS, have a major problem in that drift occurs and measurement errors diverge over time.

(Problems to be Solved by the Invention) As described above, in conventional azimuth angle detection devices, in order to obtain highly accurate azimuth angles, a gyro is used which is expensive and requires a lot of maintenance. There are problems such as slow rise time during operation, INS is required, and drift occurs and measurement errors diverge over time.

This invention was made in order to solve the above problems, and its purpose is to provide an azimuth angle detection device that has a quick start-up time, is easy to maintain, has no drift, and can obtain highly accurate azimuth angles. shall be.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, an azimuth angle detection device according to the present invention is mounted on a detected object, and detects the azimuth angle of the detected object reference axis with respect to the earth reference direction. 5. An antenna section for capturing signals from an artificial satellite mounted on the detected object and emitting orbit information including its own position and altitude based on earth coordinates; 5. a first angle detection means for identifying orbit information from the satellite signal, determining the direction of the captured satellite from this orbit information, and determining the angle between the satellite direction and the earth reference direction; a second angle detection means for determining the angle formed by the reference axis of the object to be detected; and a calculation section for calculating the azimuth of the reference axis of the object by adding and subtracting the detected angles of the first and second angle detection means. It is composed of:

(Function) The azimuth angle detection device with the above configuration uses the fact that some artificial satellites emit orbit information including their own position and altitude based on earth coordinates, and captures signals from satellites. identify the orbit information, find the direction of the captured satellite from this orbit information, find the angle between this satellite direction and the earth reference direction, and also find the angle between the satellite direction and the base axis of the detected object. , the azimuth angle of the reference axis of the detection object is determined by adding and subtracting each angle.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the configuration of the first embodiment. This embodiment is a G
It was constructed using PS (Global Positioning System).

Figure 1 Nioite, It. 12ha GPS 1sim
These antennas 11. are GPS receiving antennas that can capture Carano GPS signals. As shown in FIG. 2, for example, a flat type receiver 12 having typical receiving characteristics on one side is used. As shown in Fig. 3, these antennas 11 and 12 are installed on the rotary table l3 with their receiving surfaces facing outward and facing each other, so that they can form a pair and cover the entire sky. It has become. The rotary table l3 is mounted on a detected object (not shown) such as a vehicle, and rotates around the rotation axis b on the fP axis a from 0 @ to 36
It is rotatable by 0' and its rotation is controlled by a control signal from a rotation controller l8. Furthermore, it has a horizontal correction mechanism, which will be described later, to maintain the level and rotate the rotation axis b.
is made to coincide with the vertical axis C.

The rotation controller 18 rotates the rotation table 13 in response to a rotation drive signal supplied from an azimuth calculating section 17, which will be described later, and controls the rotation to a specified target rotation angle. Still, this rotation controller l8 is perpendicular to the reference axis (vertical axis C) of the rotary table l3, and the antennas 11, 12
is provided with an angle detector (not shown) that detects the relative angle between the reference plane a of the object to be detected and the reference plane a of the object to be detected;
The relative angle obtained by this detector is sent to the azimuth calculating section 17 as the rotation angle of the rotary table 13.

Each antenna 11. Each of the 12 receiving outputs is
After being amplified by the respective amplifiers 14 and 15 (not shown in FIG.
It is input to G. This GPS receiver 1G has 1 antenna for each
1. The GPS signals captured by each antenna 11.12 are processed separately. GP caught in 12
It identifies satellite orbit information such as the position of the S satellite with respect to earth coordinates and its altitude from the earth's surface, and calculates its own position geometrically from the orbit information. The total satellite orbit information and self-position information obtained here are obtained by the direction calculation section 17.
is man-powered.

This azimuth calculation unit 17 calculates the azimuth angle of each satellite with respect to the earth coordinates from all the satellite orbit information. Then, the azimuth angle of a specific satellite is set as a target rotation angle, and a rotation drive signal (rotation direction, rotation speed, sequence, etc.) is sent to the rotation controller 18 together with this target rotation angle to rotate the rotary table l3 to the target rotation angle. After the rotation, the rotation angle of the rotary table 13 sent from the rotation controller 18 is read, and the azimuth of the object to be detected is calculated by combining it with the satellite azimuth obtained from the satellite orbit information.

Furthermore, similar operations are performed on other satellites, and the azimuth angles obtained from each operation are averaged and output.

As the above horizontal correction mechanism, if the object to be detected is in a nearly stationary state, a simple balance type (for example, pendulum type) horizontal table or various types of horizontal tables that correct the inclination horizontally can be used. If your body is subject to significant shaking, use a spirit level etc. to adjust the rotation axis b, unless the tilt is too large to capture a sufficient number of GPS satellites to detect your position.
A similar result can be obtained by detecting the inclination of , and sending this detection result to the azimuth calculation section 17 and adding it as a parameter so that appropriate coordinate calculation can be performed.

The operation of the above configuration will be explained below with reference to FIG.

First, the horizontal correction mechanism is adjusted to hold the rotary table l3 horizontally, and the rotation axis b is aligned with the vertical axis C.

Now antenna 11. G from multiple GPS satellites at 12
When the PS signal is received, for example, as shown in FIG.
iC. Suppose that D is captured. The GPS receiver 1B, which receives the GPS signals from the antennas II and 12, calculates the positions of all the GPS satellites A to D with respect to the earth and the self-position of the object to be detected from each signal, and sends them to the azimuth calculating section 17. As shown in the figure, since the antenna 11 cannot see the GPS satellites A and BL, it is possible to detect to some extent which direction the antenna 11 is currently facing within the local horizontal plane coordinates with the position of the detected object as the origin. Furthermore, since the antenna rotation angle (rotary table rotation angle) can be determined by the rotation controller l8, the orientation of the reference axis a of the detected object can also be detected with that accuracy.

The azimuth calculation unit 17 determines in which direction and how many times the rotary table l3 should be rotated based on the sent satellite orbit information and antenna rotation angle, and generates a rotation drive signal specifying the direction and a target rotation angle specifying the amount of rotation. is given to the rotation controller l8 to control the rotation of the rotary table l3 to the target rotation angle. At this point, the turntable l3 rotates a little, and as shown in Fig. 4, the turntable moves in a direction in which antenna ■ can receive radio waves from the GPS satellite hlA, but antenna l2 cannot. Stop 3. The antenna rotation angle (orientation of the antenna) at this time becomes the azimuth angle of the GPS satellite A from the reference axis a of the detected object. Therefore,
In this azimuth calculation unit l7, if the azimuth calculated from the antenna rotation angle and the azimuth of the satellite person with respect to the earth coordinates (for example, the north-south axis) are added or subtracted, the reference circle a of the detected object is calculated.
It is possible to find the direction of the earth relative to the earth coordinates. By performing these operations on multiple satellites, measurement precision and accuracy can be increased.

Therefore, since the azimuth angle detection device with the above configuration uses GPS without using a magnetic compass or gyro, it is not affected by surrounding magnetism, has a short rise time, does not cause drift, and has high accuracy. Since the azimuth angle can be detected at any time, and the structure is simple, maintenance is also relatively easy.

The receiving characteristics of the antenna shown in Figure 2 are ideal for this device, but some antennas have a coverage area that extends to the back side of the receiving surface, so it is difficult to connect two antennas with such characteristics in parallel. If installed in two areas, the covered areas will overlap. However, even in such a case, if the reception characteristics of the two antennas are determined in advance and captured when calculating the azimuth, it is possible to detect the azimuth of the antenna that can receive a specific satellite.

FIG. 5 shows a second embodiment of the present invention, and this embodiment is also constructed using GPS. Fifth
In the figure, 21 is a normal GPS receiving antenna, and this antenna 2l is an omnidirectional AZ (azimuth) axis, E
It can be freely rotated about the L (elevation angle) axis. These antennas 21. The GPS signals captured by 22 are respectively input to amplifiers 23. After being amplified at 24, the signal is sent to a GPS receiver 25.

This GPS receiver 25 receives the G signal captured by the antenna 2l.
Calculates the self-position of the detected object from the PS signal, identifies the satellite orbit information such as the altitude and position relative to the earth of all GPS satellites within the view, and calculates the number of the captured GPS satellite from the GPS signal captured by the antenna 22. Both the satellite orbit information and the satellite capture signal (the number of the captured GPS satellite) are sent to the direction calculation section 26.

This direction calculation unit 2B is the antenna 2! 2! Azimuth angle detection from all satellite orbit information within the view obtained from! Select a target satellite as a table, and calculate the elevation angle (EL angle) and azimuth angle (AZ angle) of the target satellite. Furthermore, from the satellite orbit information and target satellite acquisition signal from the GPS receiver 25, a rotation drive signal (rotation direction, rotation speed, sequence, etc.) to the AZ controller 27 and EL controller 28, which will be described later, is generated, and the target AZ angle is determined. and EL angle, respectively, to the AZ controller 27 and the EL controller 28. It also receives information on the AZ angle and EL angle of the antenna 22 from the AZ controllers 2 and 28, which will be described later, and determines the azimuth angle of the detected object from these angle information, satellite orbit information from the GPS receiver 25, and acquisition signal of the target satellite. Calculate.

Furthermore, the above operations are performed for each satellite, and the azimuth angles obtained for each operation are averaged, for example, and output to the outside.

The AZ controller 27 and the EL controller 28 each include a rotation drive mechanism for the antenna 22 and a rotation angle detector. The rotational drive mechanism performs rotational and stationary drive control for each axis of the antenna 22 based on a rotational drive signal from the azimuth calculation unit 2B. Generally, the rotation axis (AZ axis) of the AZ controller 27 is set on the azimuth reference axis of the detected object and can rotate 360'' (all directions), and the rotation axis (EL axis) of the EL controller 28 is set on the azimuth reference axis of the detected object. It is parallel to the plane containing the axis and is rotatable by 90° or 180°.

The AZ axis and the EL axis can be driven independently, and both wheels are set on the stand to which the antenna 22 is attached or on the structure of the antenna 22 itself. In other words, the antenna 22 is A
It is made rotatable around the Z axis and the EL axis by rotation drive mechanisms of an AZ controller 27 and an EL controller 28. In addition, each controller 27. Each of the 28 angle detectors is adjusted based on the reference axis of the detected object, and is configured to constantly or periodically detect each angle of the AZ axis and the EL axis and send it to the azimuth calculator 2B.

The operation of the above configuration will be described below with reference to FIGS. 6 and 7.

First, multiple GPS satellites received by the antenna 2l,
For example, the GPS signals from satellites A-D shown in Figure 6 are
Here, satellite orbit information such as the position of each satellite with respect to earth coordinates and altitude from the earth's surface is obtained, and from this information, the self-position of the detected object with respect to earth coordinates is geometrically detected.

The satellite elevation angle with respect to the local horizontal plane at the position of the detected object is also calculated. Here, it is assumed that the AZ axis of the antenna 22 is adjusted to be perpendicular to this local horizontal plane. This method can utilize the horizontal correction mechanism described in the first embodiment.

Next, the azimuth calculation unit 2B determines the target satellite based on the above satellite orbit information, and sets its elevation angle as the target EL angle. Here, satellite A is first set as the target satellite. The EL controller 281 sends this datemark EL angle and an EL axis rotation drive signal for directing the antenna 22 toward the satellite. This rotates the antenna 22 to its target EL angle as shown in FIG. Similarly, the azimuth calculation unit 26 generates a target AZ angle and an AZ axis rotation drive signal and sends them to the AZ controller 27.

As a result, the antenna 22 is rotated to the target AZ angle. By the above operations, you can control the pointing direction of the antenna 22! 5
! ．． It can be directed to A.

On the other hand, the GPS receiver 25 captures the signal of the satellite MA from the output of the antenna 22, as shown in FIG. 6, and detects the point in time when the reception strength reaches its maximum. The azimuth calculation unit 2B rotates the antenna 22 to the detection point, makes it stationary there, and reads the AZ angle θl from the angle detector of the AZ controller 28 at this time. This angle θ1 is the angle between the reference axis of the object to be detected and the antenna 22, that is, the satellite A, in the local horizon. Therefore, in the azimuth calculation unit 2B, the angle θ2 between the satellite and the earth coordinate reference axis (for example, the north-south axis) is calculated from the satellite orbit information, and the above angle θl is added with a sign. It is possible to find the direction relative to the earth coordinates. As mentioned above, in order to increase the measurement viscosity and accuracy, it is sufficient to measure the direction using a plurality of satellites as a reference.

Therefore, since the azimuth angle detection device with the above configuration uses GPS without using a magnetic compass or gyro, it is not affected by surrounding magnetism, has a short rise time, does not cause drift, and has high accuracy. Since the azimuth angle can be detected at any time, and the structure is simple, maintenance is also relatively easy.

[Effects of the Invention] As described above, according to the present invention, it is possible to provide an azimuth angle detection device that has a fast rise time, is easy to maintain, has no drift, and can obtain highly accurate azimuth angles. can.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing the configuration of a first embodiment of the azimuth angle detection device according to the present invention, Fig. 2 is a characteristic diagram showing the reception characteristics of an antenna used in the embodiment, and Fig. 3 is a diagram showing the reception characteristics of the antenna used in the embodiment. FIG. 4 is a perspective view for explaining the positional relationship of the rotary table used for the detection object with respect to the detected object, FIG. 4 is a diagram for explaining the operation of the same embodiment, and FIG. 5 is the configuration of the second embodiment according to the present invention. 6 and 7 are diagrams for explaining the operation of the embodiment. 11. +2. 21. 22...GPS receiving antenna, l3...rotating table,! 4. 15. 23. 24・
...Amplifier, 16. 25...GPS receiver, 17.
26... Orientation calculation unit, l8... Rotation controller, 27... AZ controller, 28... EL controller, a... Detected object reference axis, b... Rotation axis, C
... Vertical axis, d... Turntable reference axis, A-D...G
PS satellite. Figure 5 Applicant's agent Patent attorney Takehiko Suzue Figure 6 Figure 7

Claims (1)

[Claims] In an azimuth angle detection device that is mounted on a detected object and detects the azimuth angle of a reference axis of the detected object with respect to an earth reference direction, the orbit is mounted on the detected object and includes its own position and altitude based on earth coordinates. An antenna unit that captures signals from artificial satellites that emit information; orbit information is identified from the satellite signals captured by this antenna unit; the direction of the captured satellite is determined from this orbit information; and the satellite direction and the earth reference direction are determined. a first angle detection means for determining the angle between the satellite direction obtained by this means and the reference axis of the detected object; An azimuth angle detection device comprising: an arithmetic unit that calculates an azimuth angle of a reference axis of a detected object by adding and subtracting a detection angle of a detection means.