JPH04315301A - Rocking compensation type antenna system - Google Patents

Abstract

PURPOSE:To inexpensively obtain the compensation type antenna system with simple constitution. CONSTITUTION:The XEL axis is selected to be an electric axis in the AZ- EL-XEL mount. The electric axis is realized by controlling the phase shifter of array antenna. The threshold level discrimination is executed as to a latitude in which a mobile body is in existence or at an elevating angle of a satellite, and the rocking compensation in the AZ-EL mount and the satellite tracing in the XEL axis are executed at a high latitude area or a low elevating angle area. The rocking compensation is executed in the AZ-EL-XEL mount and the satellite tracing is executed according to an azimuth input at the high latitude area or the low elevating angle area. The satellite tracing and the rocking compensation are executed without causing a singular point at the high latitude area or the low elevating angle area and the excellent satellite tracing and rocking compensation are executed while stopping the use of a device relating to the azimuth input and avoiding the effect of a singular point at the high latitude area or the low elevating angle area. Not a gyro compass but an inexpensive device such as a magnetic compass is used for the device relating to the azimuth input.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to an antenna device mounted on a moving body such as a ship and used for satellite communications and satellite broadcasting such as the Inmarsat system, and in particular, a swinging function that eliminates the influence of swinging of the moving body. The present invention relates to a swing-compensated antenna device.

0002

2. Description of the Related Art (1) Technical Background Directional antennas have been used for satellite communications in ships and the like. Historically, ship satellite communications
It was started in 1976 by the US Marisat satellite, and since 1982 it has been taken over and implemented by the international organization Inmarsat. In order to carry out such ship satellite communication, an antenna having a predetermined directivity is required.

For example, according to the Inmarsat Standard A technical standards for ship earth stations as of June 1987, the G/T of ship earth stations is specified to be -4 dBK or more, and antennas that meet this standard are used as parabolic antennas. When attempting to construct such a structure, a dimension of approximately 80 cm in diameter is required.

[0004] Furthermore, in order to protect the parabolic antenna from rain and the like and ensure weather resistance, a radome is required to cover the antenna. Since the parabolic antenna has a diameter of about 80 cm, the diameter of this radome is required to be, for example, about 1.2 m. The radome is a bowl-shaped member with a bottom, and is used for radio waves of at least the wavelength related to satellite communication (1
．． It is made of a material that allows the frequency (around 5 GHz) to pass through. Generally, FRP is used. Furthermore, an access hatch is provided at the bottom for operations such as maintenance and repair of the antenna.

(2) Tracking and Shaking Compensation A swing compensation type antenna device is known as a type of antenna device having such a configuration. This swing compensation antenna device is a device that has a swing compensation function in addition to a satellite tracking function.

[0006] That is, in order for an antenna mounted on a moving body such as a ship to continue to receive radio waves from a satellite well, it is necessary to drive the antenna to track the satellite. In addition, such antenna drive and its control functions are
It is possible to configure the device to perform rocking compensation. For example, a ship sways due to ocean waves, and by compensating for this oscillation, good satellite tracking can be achieved. The rocking motion of a ship includes, for example, roll and pitch. Roll corresponds to horizontal shaking, and pitch corresponds to vertical shaking, and to compensate for both, it is necessary to mechanically or electronically drive the antenna horizontally and vertically. For this reason, various techniques for driving antennas for the purpose of vibration compensation and the like have been developed.

(3) 3-axis mechanical axis device When a parabolic antenna or the like is used as an antenna, it is possible to provide three axes for driving the parabolic antenna and configure all of them as mechanical axes.

An example of a three-axis configuration is the so-called AZ-
There is an EL-XEL mount.

[0009] Here, the AZ axis represents the azimuth axis,
This is the axis related to the direction of the antenna. Further, the EL axis represents an elevation axis, and is an axis related to the elevation angle of the antenna. Furthermore, the XEL axis represents a cross-elevation axis, and is an axis related to an angle in a plane perpendicular to the rotation plane of the EL axis.

[0010] In an antenna device having a three-axis configuration, such as a mount, if all the axes are configured as mechanical axes, the mechanical design becomes complicated and the device tends to be expensive. For this reason, proposals have been made to reduce the number of axes and realize a device with two mechanical axes.

(4) 2-axis mechanical axis device As such a device, for example, “2-axis Az-El antenna mount control method” (Yuki et al., Institute of Electronics and Communication Engineers, S.
ANE83-53, pp1-6), “Reducing the size and weight of maritime satellite communication digital ship station antenna systems” (Shiokawa et al., Institute of Electronics and Communication Engineers, SANE84-19, pp.
There is an AZ-EL mount disclosed in 17-24) and others.

[0012] With this configuration as well, it is possible to track the satellite while compensating for rocking. However, such a mount has a problem in that a singularity occurs.

A singular point is a point that appears, for example, in the zenith direction and causes a tracking error when the antenna is oriented in this direction under swing conditions. In order to deal with this singularity, it is necessary to use lightweight and robust materials for the antenna and the frame that supports it, reduce the load on the motor that drives the antenna, etc., and to use a relatively high-performance motor. Adopts high-performance AC servo motor, correspondingly high-performance AC
There is a method of employing a servo control circuit and driving the antenna with a high-performance servo system. Furthermore, there are ways to reduce tracking errors near singular points by improving control software.

However, such measures require special materials,
Since the use of expensive circuits is required, the price of the equipment cannot be avoided. Further, even when these measures are taken, there is data showing that the tracking error near the singular point is about 10°.

(5) 1-axis mechanical axis 2-axis electronic axis device As a means to solve such problems, it is effective to use one of the plurality of axes as an electronic axis. The electronic axis can be realized by a so-called phased array antenna. As an example of a device having such an electronic axis, there is a "Phased Array Antenna for
r MARISAT Communications
”, Folkebolinder, Microwave
There is an apparatus disclosed in Journal, 1978.12 pp39-42.

This axis is a device in which the AZ axis is a mechanical axis and the EL axis is realized by shifting the phase of a plurality of array antennas formed on two planar antennas (array antennas).

That is, a phase shifter is connected to each antenna element arranged in a matrix on an array antenna, and the amount of phase shift of a signal related to each antenna element is controlled by this phase shifter. By controlling the amount of phase shift, the beam directivity characteristic of the antenna can be switched to a predetermined characteristic.

[0018] Therefore, if the beam directivity characteristics are changed in the elevation angle direction by this phase shifter control, the EL axis can be realized as the electronic axis. Furthermore, since the beam directivity characteristics can be changed in a direction perpendicular to this direction, one axis is further realized by the electronic axis.

However, even when an electronic axis is used in this way, a phase shifter must be provided for each antenna element, which makes the device configuration bulky and complicated, and increases the device price, which limits its application. The problem arises that the

(6) Device with 2-axis mechanical axis and 1-axis electronic axis In order to solve these problems, it is sufficient to use a 2-axis mechanical axis and 1-axis electronic axis. As a device with such a configuration, the applicant of the present application has previously proposed a swing compensation type antenna device that maintains tracking and swing compensation performance and realizes a reduction in device cost (Japanese Patent Application No. Hei 2- 339317 "Antenna swing compensation method and swing compensation antenna device").

[0021] Furthermore, Japanese Patent Application Laid-open No. 110950/1983 discloses a ship antenna for satellite communication which is configured with the AZ axis and the EL axis as mechanical axes, and also has means for switching beam directivity characteristics.

[0022]

In the device previously proposed by the applicant of the present invention, for example, in an X1-Y-X2 mount, the X1 axis and the Y axis are used as mechanical axes, and the X2 axis is configured as an electronic axis. Therefore, it is conceivable to apply the technology proposed earlier by the present applicant to the above-mentioned AZ-EL-XEL mount. That is, the AZ axis and the EL axis may be used as mechanical axes, and the XEL axis may be used as an electronic axis.

On the other hand, in order to track a satellite, a compass is required to detect changes in the orientation of the mobile object on board. As such a compass, a gyro compass that can obtain highly accurate azimuth information has conventionally been used. This gyrocompass is more effective than other inexpensive devices, such as a magnetic compass, in that it can measure direction with small errors even in high latitude areas. However, this gyro compass has a problem in that it is not suitable for equipping small vessels because of its high price.

The present invention was made with the aim of solving these problems, and it is possible to track satellites while maintaining sufficient accuracy even in high latitude areas where magnetic compass errors increase. AZ-EL-X is a swing-compensated antenna device configured with the XEL axis as the electronic axis.
The purpose is to realize this using an EL mount.

[0025]

[Means for Solving the Problems] In order to achieve the above object, the applicant of the present application proposes a swing compensation type antenna device having the following configuration.

[0026] First, the applicant of the present application has proposed, as claim 1, an antenna having a predetermined beam directivity characteristic, an AZ axis which is a mechanical axis related to the azimuth, an EL axis which is a mechanical axis related to the elevation angle, and an antenna having a predetermined beam directivity characteristic.
X, which is the electronic axis related to the angle in the plane perpendicular to the rotation plane of the L axis
The EL axis, a tracking control means that causes the antenna to track the satellite according to the elevation angle and relative azimuth of the satellite, and rocking that is the deviation of the antenna caused by the rocking of the mobile body on which the antenna is mounted. In a swing compensating antenna device having a swing compensating means for compensating the component, in a high latitude area where a moving object is located at a predetermined latitude or higher,
A high latitude region control means is provided to control the tracking control means and the vibration compensation means so that the vibration compensation is performed by the axis and the EL axis, and the satellite tracking is performed by the XEL axis. In other regions, we propose a swing-compensated antenna device that tracks satellites using an AZ-EL-electronic XEL mount.

Next, as claim 2, the applicant of the present application has proposed that in a low elevation area where the elevation angle of the satellite is less than a predetermined angle,
comprising a low elevation angle area control means for controlling the tracking control means and the swing compensation means so as to perform swing compensation using the AZ axis and the EL axis, and tracking of the satellite using the XEL axis;
We propose a swing-compensated antenna device that tracks satellites using an AZ-EL mount in low elevation angle areas and an AZ-EL-electronic XEL mount in other areas.

Furthermore, the applicant of the present application proposes the following swing compensation type antenna device as a claim dependent on these claims 1 and 2.

First, a third aspect of the present invention provides an azimuth error detection means for detecting an azimuth error of an antenna by simultaneously detecting a reception level signal representing the reception level of the antenna with a signal related to switching of beam directivity characteristics; azimuth change input means for inputting changes from a device such as a magnetic compass, and the tracking control means responds to the azimuth error in high latitude areas or low elevation angle areas, and in response to the azimuth change in other areas, It is characterized by correcting the relative orientation of the satellite.

A fourth aspect of the present invention is characterized in that the tracking control means controls the orientation of the antenna by rotating the AZ axis by the relative orientation of the satellite in areas other than high latitude areas or low elevation angle areas.

[0031] Claim 5 provides a satellite azimuth/elevation angle calculation means for calculating the elevation angle and absolute azimuth of the satellite, and means for calculating the relative azimuth of the satellite by subtracting the moving body azimuth from the absolute azimuth of the satellite. Features.

[0032] According to a sixth aspect of the present invention, the satellite azimuth and elevation angle calculation means includes means for inputting the latitude and longitude of the moving object, and calculates the elevation angle and absolute azimuth of the satellite from a known satellite orbit based on the latitude and longitude of the moving object. It is characterized by

A seventh aspect of the present invention is characterized in that the correction of the relative orientation of the satellite by the tracking control means is performed as a correction of the orientation of the moving body.

[0034] According to an eighth aspect of the present invention, there is provided a search control means for causing the antenna to search for the relative orientation of the satellite.

Claim 9 provides that the antenna has antenna elements arranged in 2 to 3 rows and N (N is a natural number) columns with the beam switching direction of the XEL axis as the rows, and at least 2 rows arranged at the ends of the antenna element arrangement. XEL
It is characterized by having a plurality of phase shifters that shift the phase of the received signal of the corresponding row by an amount corresponding to the axis control amount.

[0036] Claim 10 is characterized in that the radome is provided with a bottomed bowl-shaped radome that covers the antenna, and legs that eccentrically support the antenna on the bottom surface of the radome, and that the access hatch opens at a position substantially directly below the antenna on the bottom surface of the radome. do.

[0037]

[Operation] According to claim 1 of the present invention, when the latitude where the moving body exists is in a high latitude region (when it is above a predetermined latitude), the oscillation compensation is performed by the AZ axis and the EL axis, and the satellite tracking is performed by the XEL axis.

[0038] This operation corresponds to performing vibration compensation using the AZ-EL-XEL mount in low latitude areas and using the AZ-EL mount in high latitude areas. This method focuses on the fact that when the satellite to be tracked is a geostationary satellite stationary on the earth's equator, the angle (elevation angle) at which the satellite is viewed is low in high latitude regions. That is, while the singular point of the AZ-EL mount antenna device is almost in the zenith direction, the elevation angle of the satellite is low in high latitude regions, and the antenna can be operated far from the singular point. Therefore, in high latitude areas, the AZ-EL mount can also perform tracking and vibration compensation while eliminating singularity errors.

On the other hand, in claim 1, the AZ-EL-XEL mount can perform satellite tracking and swing compensation without generating a singular point in the zenith direction in a low latitude region.

[0040] As a result, satellite tracking and oscillation compensation can be carried out in both high latitude and low latitude areas without significantly causing the influence of singularities.

In claim 2, low elevation angle area control means is used in place of the high latitude area control means in claim 1. The high latitude area control means in claim 1 focuses on the fact that when the satellite to be tracked is a geostationary satellite, the angle of elevation in high latitude areas is low.
The low elevation angle area control means in , which switches control based on information about the elevation angle of the satellite, regardless of whether the satellite is a geostationary satellite or not. That is, in low elevation angle areas, the device is mounted as an AZ-EL mount, and in high elevation angle areas, the device is mounted as an AZ-EL-XEL mount.
Each will be used for vibration compensation.

In this claim as well, the same effect as in claim 1 can be obtained.

In claim 3, the information taken in from the azimuth error detection means or the azimuth change input means is used for correcting the relative orientation of the satellite while being switched as appropriate by the tracking control means. In other words, since the orientation (relative orientation) of the satellite with respect to the mobile object changes depending on the rotation of the mobile object, in order to perform satellite tracking, it is necessary to correct the relative orientation of the satellite according to this change. preferable. For this correction, antenna reception levels can be used in high latitude areas or low elevation angle areas, and external devices such as magnetic compasses can be used in other areas.

Particularly in high latitude regions where errors in the magnetic compass are likely to occur, by eliminating changes in the direction taken in from the magnetic compass, and therefore the errors, and by utilizing the direction error obtained by synchronous detection of the reception level, Tracking is performed with high precision.

[0045] In claim 4, the AZ axis is rotated by the relative azimuth of the satellite in a low latitude region or a high elevation angle region. Thereby, the azimuth, elevation angle, and beam directivity characteristics of the antenna can be switched and controlled using a simple control algorithm.

In claim 5, the elevation angle and absolute azimuth of the satellite are determined by the satellite azimuth/elevation angle calculation means. From this absolute azimuth, the moving object azimuth is subtracted to obtain the relative azimuth of the satellite. Accordingly, in claim 5, the elevation angle, absolute azimuth, and moving body azimuth of the satellite are used as information on which the antenna tracks the satellite.

[0047] In claim 6, the latitude and longitude of the mobile object are input, and based on these, the elevation angle and absolute azimuth of the satellite are determined from the known satellite orbit. Therefore, in claim 6, tracking control of the antenna is executed by inputting the latitude and longitude of the moving object in addition to the azimuth of the moving object.

[0048] In claim 7, the correction of the relative orientation of the satellite is performed as the correction of the mobile object orientation. The mobile heading is subtracted from the satellite's absolute heading. This determines the relative orientation of the satellite, so
Correcting the relative orientation of the satellite is achieved by modifying the mobile orientation.

In claim 8, the relative orientation of the satellite is searched for by the search control means and the antenna. Therefore, it is possible to obtain the relative orientation of the satellite without inputting the absolute orientation of the satellite and the orientation of the mobile object.

[0050] In the ninth aspect of the present invention, the directivity characteristics of the beam are switched and controlled by controlling the amount of phase shift for the phase shifter of the antenna.

[0051] That is, in the antenna, 2 to 3
Antenna elements are arranged in rows and N columns, and phase shifters are provided for at least the antenna elements in the rows at both ends. The phase shift amount of this phase shifter is determined according to the XEL axis control amount. When the phase shift amount of the phase shifter is controlled, the beam directivity characteristic of the antenna changes. Therefore, the XEL axis related to the electronic axis can be easily realized by an array antenna. Furthermore, since the rows at both ends are enough to provide phase shifters, the device configuration is relatively simple.

In the tenth aspect of the present invention, the antenna is eccentrically supported on the bottom surface of the radome by the legs. As a result, there is room to provide an access hatch at a position directly below the antenna on the bottom surface of the radome. Therefore, in this claim, even if the shape of the antenna is small, it is possible to provide an access hatch.

[0053]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings.

(1) Actual configuration of embodiment FIG. 1 shows the actual configuration of a swing compensation type antenna device according to an embodiment of the present invention.

The embodiment shown in this figure includes an array antenna 12 having antenna elements 10 arranged in three rows and four columns. On the back of the array antenna 12, for example, a receiver front end and a phase shifter (PS) are installed.
er), a synthesizer, etc. are arranged (not shown). As will be described later, the XEL axis is realized as an electronic axis by controlling the phase shifter on the back surface of the array antenna 12.

The array antenna 12 is rotatably supported by an azimuth axis frame 16 through an elevation axis 14. An elevation axis motor 18 is attached to the azimuth axis frame 16, and this elevation axis motor 18 is connected to gears 20 and 2.
2. It is connected to one end of the elevation axis 14 by a belt 24. Therefore, when the elevation axis motor 18 is driven to rotate, the array antenna 12 rotates about the elevation axis 14. That is, the elevation axis motor 18 is a motor that mechanically realizes the EL axis.

The azimuth axis frame 16 is integrally formed with the azimuth axis 26. The azimuth shaft 26 is provided at the lower part of the azimuth shaft frame 16, and is rotatably fixed to the support leg 28. That is, when the azimuth axis 26 rotates, the azimuth axis frame 16, and therefore the array antenna 22, rotates and its orientation changes.

An azimuth axis motor 30 is attached to the support leg 28. The azimuth axis motor 30 has gears 32 and 3.
4. Connected to the azimuth axis 26 by a belt 36. Therefore, when the azimuth axis motor 30 rotates, the azimuth axis 2
6 rotates. In other words, the azimuth axis motor 30
This is a motor that drives the azimuth axis 26 related to the mechanical axis.

Furthermore, in this embodiment, the supporting legs 28
is attached and fixed to the bottom surface of the radome 38. The radome 38 is made of a material that can transmit radio waves related to the transmission and reception frequency of the array antenna 12. A common material is FRP.

The radome 38 has a bowl-like shape with a bottom, and the supporting legs 2 are placed at a slightly eccentric position on the bottom surface.
8 is attached. The support leg 28 has an inverted L-shape, and therefore has the function of eccentrically supporting the array antenna 12 and its surrounding members on the bottom surface of the radome 38. As a result of this eccentric support, a space having a constant area is created in the center of the bottom surface of the radome 38 (directly below the array antenna 12). In this embodiment, an access hatch 40 is provided in this space.

[0061] The access hatch 40 is connected to the array antenna 1.
This is an opening related to maintenance and inspection, etc. of No. 2. That is, an operator inserts his or her arm or the like through the access hatch 40 to carry out maintenance and inspection of the array antenna 12 and its surrounding structure.

Therefore, in this embodiment, the radome 38 is made smaller by using the small array antenna 12 as the antenna, and the access hatch 40 allows maintenance and inspection of the array antenna 12.

In this embodiment, as described above, the azimuth axis 26 is rotated by the azimuth axis motor 30, and the elevation axis 14 is rotated by the elevation axis motor 18, respectively. Therefore,
In this embodiment, the so-called AZ axis is realized as a mechanical axis by the azimuth axis 26 and the azimuth axis motor 30, and the so-called EL axis is realized also as a mechanical axis by the elevation axis 14 and the elevation axis motor 18. Further, in this embodiment, the XEL axis is electronically realized by phase shifting of antenna elements arranged in rows and columns on the array antenna 12.

FIG. 2 shows the shaft configuration of this embodiment. As shown in this figure, the shaft configuration of the device according to this embodiment is a so-called AZ-EL-XEL mount. Of the three axes shown in this figure, namely the AZ axis, the EL axis, and the XEL axis, the AZ axis and the EL axis are realized as mechanical axes as described above, and the XEL axis is realized as an electronic axis.

(2) Array antenna FIG. 3 shows the circuit configuration of the array antenna 12 that realizes the XEL axis as the electronic axis.

As shown in this figure, the antenna elements 10 are arranged in a matrix of 3 rows and 4 columns. This antenna element 10 is formed as an electrode on an antenna substrate of an array antenna 12. The antenna board is usually
It is laminated with the power supply board on the back via an insulator. A circuit related to each antenna element 10 is arranged and formed on this power feeding board.

Each antenna element 10 is connected to combiners 42-1, 42-2, and 42-3 in each row among the circuits provided on the feeding board. That is, each combiner 42 combines the signal outputs of the antenna elements 10 related to the row that it is in charge of. Among these three combiners 42, the combiners 4 related to the rows at both ends of the antenna element 10 array
2-1 and 42-3 are phase shifters 44-1 and 4, respectively.
Connected to 4-3. Phase shifters 44-1 and 44-3
shifts the phase of the signal supplied from the synthesizer 42-1 or 42-3 using the signal supplied from the phase shifter drive circuit 46. Phase shifter 44-1, combiner 42-2, and phase shifter 4
The outputs of 4-3 are both supplied to a combiner 48. A combiner 48 combines the signals from these and supplies it to an antenna output processing section, which will be described later.

The phase shifter driving circuit 46 is a circuit that drives the phase shifters 44-1 and 44-3 in accordance with a phase shifter control signal. The phase shifter control signal is a signal having a value corresponding to the beam directivity characteristic to be realized in this array antenna 12, and the phase shifter drive circuit 46 controls the phase shifter 44-1 to realize this beam directivity characteristic. and 44-3.

FIG. 4 shows an example of beam control of the array antenna 12 in this embodiment as antenna gain characteristics, and Table 1 shows this example with phase shifters 44-1 and 44-1.
It is shown as the amount of phase shift in 4-3.

[0070]

[Table 1]

In the control example according to FIG. 4 and Table 1, the phase shifter 44
This is an example in which -1 and 44-3 are 3-bit phase shifters. That is, the phase shifters 44-1 and 44-3 are phase shifters whose phase shift amount is controlled according to the value of a 3-bit digital signal supplied from the phase shifter drive circuit 46.

The value of this digital signal, that is, the signal supplied from the phase shifter drive circuit 46 to the phase shifters 44-1 and 44-3, is in one-to-one correspondence with the beam number.

The beam number is a number assigned to each beam of the array antenna 12, as shown in FIG. For example, beam 4 has the maximum gain when the beam inclination is 0°, and beam 3 and beam 5
is a beam adjacent to this beam 4. When beam 4 is to be realized, a digital signal indicating 0° is supplied to the phase shifter 44-1, and a digital signal indicating 0° is also supplied to the phase shifter 44-3. Further, in order to realize beam 3, a digital signal indicating -30° is supplied to the phase shifter 44-1, and a digital signal indicating +30° is supplied to the phase shifter 44-3.

The change in the beam inclination thus obtained is a change along the row arrangement direction in FIG. That is, the outputs are combined for each row of the antenna elements 10, and the rows at both ends are phase-shifted, so that the beam directivity changes along the row arrangement direction of the antenna elements 10. As shown in FIG. 1, this direction is set perpendicular to the rotation plane of the elevation axis 14, so
The EL axis will be realized.

(3) Circuit Configuration of First Embodiment Next, an embodiment of the present invention having such a substantial configuration and including the array antenna 12 will be described. FIG. 5 shows the overall circuit configuration of a swing-compensated antenna device according to a first embodiment of the present invention.

As shown in this figure, this embodiment includes an array antenna 12 having the above-described configuration, and a mechanical axis drive unit that drives the azimuth axis 26 and the elevation axis 14, which are the mechanical axes of the array antenna 12. 50 and AZ to the mechanical shaft drive section 50.
A control amount calculation unit 52 supplies the axis control amount and the EL axis control amount and calculates a phase shifter control amount indicating the phase shift amount of the phase shifter 44 in the array antenna 12;
An azimuth/elevation angle input section 54 inputs the position of a moving object from a system such as an azimuth/elevation angle input section 54, which calculates the satellite elevation angle and azimuth and supplies the obtained satellite elevation angle and azimuth to the control amount calculation section 52. is taken in, and according to this information, either the azimuth input from a magnetic compass or the like or the azimuth error related to the antenna output is selected, and the phase shifter control amount supplied from the control amount calculating section 52 is used for phase shifter control. A phase shifter mode switching section 56 that switches and supplies signals to the array antenna 12;
An antenna output processing section 58 takes in the output from the synthesizer 48, performs predetermined processing, and outputs a received level signal; It is comprised of an azimuth error detection means 60 that performs synchronous detection using a switching signal to obtain an azimuth error, and a rocking detection means 62 that detects the rocking of a moving object, such as a ship, on which it is mounted.

[0077] Each part will be explained separately below.

(3.1) Mechanical Shaft Drive Section FIG. 6 shows the circuit configuration of the mechanical shaft drive section 50.

The mechanical axis drive section 50 shown in this figure includes an azimuth axis motor 30 that drives the azimuth axis 26 and a control circuit 64.
, a depression axis motor 18 that drives the elevation axis 14, and a control circuit 66. Further, AZ-axis angle detection means 68 for detecting the angle of the azimuth axis 26 and EL-axis angle detection means 70 for detecting the angle of the elevation axis 14 are provided, and the AZ-axis drive means 64 and the EL-axis drive means 66 respectively. It is connected to the.

AZ axis drive means 64 and EL axis drive means 6
6 are the azimuth (AZ) axis motor 30 and the elevation angle (E
This is a circuit for controlling the L) axis motor 18, and is a means for driving and controlling the azimuth axis 26 or the elevation axis 14 in accordance with the AZ axis control amount and the EL axis control amount supplied from the control amount calculating section 52.

[0081] Therefore, the mechanical axis driving section 50 drives the mechanical axes (AZ axis and EL axis) related to the array antenna 12. The operation of each member has already been disclosed in Japanese Patent Application No. 3-40297, which was previously proposed by the applicant of the present application, so the details will be omitted here.

(3.2) Controlled amount calculation section FIG. 7 shows the configuration of the control amount calculation section 52.

As shown in this figure, the control amount calculation section 5
2 includes an AZ-axis control amount calculation means 72, an EL-axis control amount calculation means 74, and a phase shifter control amount calculation means 76. The AZ-axis control amount calculation means 72 calculates the AZ-axis control amount as EL.
The axis control amount calculation means 74 is means for calculating the EL axis control amount, and the phase shifter control amount calculation means 76 is means for calculating the phase shifter control amount.

These control amount calculations are executed based on the satellite elevation angle and satellite azimuth supplied from the azimuth/elevation angle input section 54. The satellite elevation angle is the angle at which the satellite is looked up at a location where a moving body, such as a ship, on which the device according to this embodiment is mounted is located. If the satellite is a geostationary satellite located on the equator, the satellite elevation angle will be small in high latitude areas and large in low latitude areas. Further, the satellite azimuth is the azimuth of the satellite with respect to the moving body, that is, the relative azimuth, and is not the absolute azimuth, for example, based on the meridian.

Furthermore, the AZ-axis control amount calculation means 72, EL
The shaft control amount calculation means 74 and the phase shifter control amount calculation means 76 take in information regarding roll and pitch from the swing detection means 62. Here, the roll is a component representing the rolling motion of a ship or the like on which the device is mounted, and the pitch is a component representing the pitching motion. The AZ-axis control amount calculation means 72, the EL-axis control amount calculation means 74, and the phase shifter control amount calculation means 76 control the azimuth and elevation angle of the array antenna 12 according to the roll and pitch, and further switch the beam directivity characteristics. In order to achieve this, each control amount is calculated.

The calculation of this control amount is performed using different algorithms depending on the tracking mode switching signal. That is, the AZ-axis control amount calculation means 72 and the EL-axis control amount calculation means 74 take in the tracking mode switching signal from the phase shifter mode switching section 56 and switch the calculation algorithm of the AZ-axis control amount and the EL-axis control amount. The tracking mode switching signal is a signal that changes in value depending on whether the latitude where the moving body exists is greater than or equal to a predetermined latitude. That is, the AZ-axis control amount calculation means 72 and the EL-axis control amount calculation means 74 calculate the control amount using different algorithms depending on the latitude.

(3.2.1) Controlled Variable Calculation Algorithm Next, the controlled variable calculation algorithm in the controlled variable calculating section 52 having such a configuration will be explained.

FIG. 8 shows the relationship between the orthogonal coordinate system and the polar coordinate system.

In this example, assuming that the moving body on which the device is mounted is a ship, the orthogonal coordinate system for the device is:
It can be set as a right-handed coordinate system in which the bow direction is the positive direction of the X-axis and the zenith direction is the positive direction of the Z-axis. When the X, Y, and Z axes of the orthogonal coordinate system are set in this way, when this coordinate system is converted to a polar coordinate system, φ represents the relative orientation of the satellite, and θ represents the 90° - satellite elevation angle, respectively. Become. In this case, since the distance to the satellite does not matter, conversion between the two coordinate systems is possible based on the following equation (1).

[0090]

[Math 1]

FIG. 9 shows a polar coordinate system related to the AZ-EL mount when roll and pitch occur in the polar coordinate system as shown in FIG. That is, the contents of the coordinate transformation are illustrated.

In this coordinate transformation, the transformation related to roll and the transformation related to pitch are considered separately. That is, the roll angle r related to the rolling motion and the pitch angle p related to the pitching motion are considered separately.

That is, in the polar coordinate system shown in FIG. 8, the coordinates are rotated by pitch angle p around the Y axis, and then the coordinates are rotated by roll angle r around X(1), which is the rotated X axis. Rotate. Then, the Z axis first shifts to Z(1) due to the pitch angle p, and then shifts to Z(2) due to the roll angle r.

Such a transformation is an orthogonal transformation using an orthogonal matrix as shown in the following equation (2).

[0095]

[Math 2]

For the convenience of the following explanation, the position of the satellite S in the orthogonal coordinate system will be expressed as (x, y, z), and the position when the polar coordinate system after coordinate conversion is further converted to the orthogonal coordinate system will be expressed as (x, y, z). Let it be expressed as (x2, y2, z2). Further, φ in the polar coordinate system after coordinate transformation will be expressed as φc, and θ will be expressed as η.

(3.2.2) Algorithm for calculating the control amount in high latitude areas First, the algorithm for calculating the control amount in high latitude areas will be explained.

[0098] The term "high latitude area" as used herein refers to an area to which a moving body (ship) carrying the device is located if the position is above a predetermined latitude. That is, this is a case where the current latitude is determined to be equal to or higher than a predetermined latitude by the phase shifter mode switching unit 56, which will be described later, and the operation based on this algorithm is started when the control amount mode switching signal takes a predetermined value. Ru.

In this case, the basic equation related to the control amount calculation is as shown in equation (3).

[0100]

[Math 3]

[0101] This equation (3) calculates the control angle φc related to the azimuth axis 26 and the elevation axis 1 after performing orthogonal transformation related to pitch and roll to the orthogonal coordinate system represented by
This is an equation showing that the swing compensation is performed by further performing orthogonal transformation using the control angle η according to 4. That is, this formula (3)
is the basic calculation formula related to AZ-EL mount.

[0102] By transforming this equation (3), the azimuth axis control angle φc
When the orthogonal matrix related to the angle η and the elevation axis control angle η is further shifted, the following equation (4) is obtained.

[0103]

[Math 4]

[0104] The left side of this equation uses the above equation (2),
It can be converted sequentially. That is, since the matrix related to the azimuth axis control angle φc is a matrix related to the Z axis, the matrix shown at the bottom in equation (2) can be used, and the orthogonal matrix related to the elevation axis control angle η is A central orthogonal matrix can be used. Therefore, when the left side of equation (4) is modified based on this, a three-dimensional vector is obtained as expressed in equation (5) below.

[0105]

[Math 5]

Naturally, this vector includes only the azimuth axis control angle φc and the elevation axis control angle η.

Similarly, when the right side of equation (4) is transformed, it becomes as follows.

[0108]

[Math 6]

Using this equation (6), the orthogonal coordinates of the satellite S after coordinate transformation using the pitch angle p and the roll angle r can be determined as a three-dimensional vector.

Equations (5) and (6) thus obtained
), paying attention to z(2), it can be seen that the elevation axis control angle η is expressed by the following equation (7).

[0111]

[Math 7]

[0112] Also, if we pay attention to x(2) and y(2), we can see that the azimuth axis control angle is expressed as follows.

[0113]

[Math. 8]

[0114] Therefore, when the latitude obtained by the azimuth/elevation angle input section 54 is equal to or higher than a predetermined latitude, and the value of the tracking mode switching signal accordingly becomes a value indicating a high latitude area, the control amount calculation is performed. It can be seen that the unit 52 may perform calculations based on equations (7) and (8). That is, the aforementioned AZ-axis control amount calculation means 72 calculates the AZ-axis control amount based on equation (8) in high latitude areas, and the EL-axis control amount calculation means 74 calculates the EL-axis control amount based on equation (7). do.

[0115] The mechanical axis drive unit 50 is driven by the AZ-axis control amount and EL-axis control amount obtained in this way.
Swings related to the antenna 12 will be compensated for. At this time, the phase shifter control amount calculation means 76 executes tracking of the satellite.

(3.2.3) Controlled amount calculation algorithm in low latitude regions Next, when the latitude obtained by the azimuth/elevation angle input section 54 is less than a predetermined latitude, that is, the controlled amount calculation section 52 in low latitude regions The control amount calculation algorithm will be explained.

In this case, the basic calculation formula is as shown in the following formula (9).

[0118]

[Math. 9]

That is, this basic calculation formula performs orthogonal transformation on the orthogonal coordinates using the pitch angle p and roll angle r, and then performs orthogonal transformation using the azimuth axis control angle φc, the elevation axis control angle η, and the XEL axis control angle ξ. This is an attempt to compensate for the fluctuation. That is, in this example, in low latitude areas, the AZ-EL-XEL mount allows
Swing compensation will be performed.

[0120] Here, in order to simplify the calculation, an assumption is made regarding the azimuth axis control angle φc according to the following equation (10).

[0121]

[Math. 10]

That is, the relative azimuth φ of the satellite is set to the azimuth axis control angle φc. The AZ-axis control amount calculation means 72
As the Z-axis control amount, an amount representing the satellite azimuth (relative) supplied from the azimuth/elevation angle input section is output. This causes the azimuth axis 26 to rotate by the relative azimuth of the satellite.

However, the present invention is not limited to such an assumption. That is, the azimuth axis control angle φc
may be set according to other assumptions.

Under the assumption of such equation (10), equation (9
) is transformed into the following equation (11).

[0125]

[Math. 11]

That is, among the orthogonal matrices in equation (9), only the orthogonal matrices related to the elevation axis control angle η and the XEL axis control angle ξ are moved to the left side.

[0127] On the left side of equation (11), the orthogonal matrix relating to the elevation axis control angle η and the XEL axis control angle ξ can be expressed using the orthogonal matrix relating to the Y axis of equation (2). When the left side of equation (11) expressed as is transformed, it becomes as follows.

[0128]

[Math. 12]

That is, the left side of equation (11) is expressed only by the elevation axis control angle η and the XEL axis control angle ξ.

Next, when the right side of equation (11) is subjected to a second and similar modification, equation (13) is obtained.

[0131]

[Math. 13]

In this case, focusing on y(3) among the components of the orthogonal coordinates of the satellite obtained by orthogonal transformation using the pitch angle p, roll angle r, and relative orientation φ of the satellite, Equation (12)
By deforming equation (13), the following equation (14) is obtained.

[0133]

[Math. 14]

That is, the XEL axis control angle is determined by the Y coordinate y(3) of the satellite after orthogonal transformation.

Similarly, focusing on x(3) and z(3), which are the x and z coordinates of the satellite after orthogonal transformation, the elevation axis control angle η is expressed as follows.

[0136]

[Math. 15]

[0137] Therefore, in this embodiment, if the moving body (ship) on which the device is installed is located in a low latitude area,
The EL axis control amount calculation means 74 calculates the EL axis control amount, which is the elevation axis control angle, based on equation (15) and supplies it to the mechanical axis drive section 50.

[0138] Furthermore, the phase shifter control amount calculation means 76 calculates the equation (
14), the phase shifter control amount, which is the XEL axis control angle ξ, is determined and supplied to the phase shifter mode switching unit 56.

[0139] In this way, even when the satellite is close to the zenith direction, it is possible to suitably compensate for the rocking (roll and pitch) without causing any errors.

(3.3) Azimuth/elevation angle input section In Fig. 10,
The configuration of an azimuth/elevation angle input section 54 that supplies information regarding the satellite elevation angle and azimuth to the control amount calculation section 52 is shown.

[0141] The azimuth/elevation angle input unit 54 has means for inputting and storing the position of a moving object from a navigation device such as a GPS. That is, in this azimuth/elevation angle input section 54, a latitude register 78 and a longitude register 80 are used. The latitude register 78 stores latitude among information supplied from a GPS or the like. Similarly, longitude register 80 stores longitude. The latitude stored in the latitude register 78 is supplied to a phase shifter mode switching unit 56 having a configuration described later.

The azimuth/elevation angle input section 54 is provided with a satellite azimuth/elevation angle calculating means 82 for taking in the latitude and longitude from the latitude register 78 and the longitude register 80 and calculating the elevation angle and absolute azimuth of the satellite. That is, if the position of the satellite is known, the elevation angle and absolute azimuth of the satellite can be determined using this position, latitude, and longitude. Here, the absolute azimuth is the azimuth of the satellite with respect to the meridian.

The satellite elevation angle determined by the satellite azimuth/elevation angle calculating means 82 is supplied to a satellite elevation angle register 84 . The satellite elevation angle register 84 temporarily stores the satellite elevation angle supplied from the satellite azimuth and elevation angle calculation means 82, and
supply to. Note that step tracking is executed for this satellite elevation angle register 84 by a step tracking circuit (not shown). By this step track, the azimuth/elevation angle and beam directivity characteristics of the array antenna 12 are switched, and the operation of the apparatus is adjusted so that the reception level at the antenna output processing section 58 is improved. The structure of the step track circuit is shown in Japanese Patent Application No. 2-240413 filed earlier by the applicant of the present application.

On the other hand, in this azimuth/elevation angle input section 54, the moving body azimuth register 86 and the satellite azimuth register 88
is provided. The mobile object orientation register 86 is a register that stores the orientation of the mobile object related to mounting. That is, the input from a magnetic compass or the like in low latitude areas, and the azimuth error obtained by the azimuth error detection means 60 in high latitude areas, are selected by the phase shifter mode switching unit 56 as described later, and the azimuth/elevation input unit 54. This heading error or compass input is input to an adder 90 preceding the mobile heading register 86. This adder 90 adds the moving object azimuth stored in the moving object azimuth register 86 and the azimuth error or compass input supplied from the phase shifter mode switching section 56, and determines the moving object azimuth based on the addition result. The contents of register 86 are updated.

[0145] An adder 92 is provided downstream of the moving body orientation register 86. This adder 92 contains, in addition to the contents of the mobile object azimuth register 86, the satellite azimuth and elevation calculation means 8.
The absolute azimuth of the satellite determined by 2 is input. This adder 92 subtracts the contents of the mobile object azimuth register 86, that is, the mobile object azimuth, from the absolute azimuth of the satellite determined by the satellite azimuth/elevation angle calculation means 82 to obtain the relative azimuth of the satellite. The relative orientation of the satellite determined by the adder 92 is stored in the satellite orientation register 88 and further supplied to the control amount calculation unit 52. Therefore, the direction and
In the elevation angle input section 54, the satellite elevation angle and the relative azimuth of the satellite are obtained from the latitude and longitude obtained by GPS, etc., and the moving object direction is determined based on the azimuth error or compass input supplied from the phase shifter mode switching section 56. Through the correction, the relative orientation of the satellite will be corrected.

Note that step tracking is performed on the moving body azimuth register 86 as well as in the satellite elevation angle register 84.

(3.4) Phase shifter mode switching unit FIG. 11 shows the circuit configuration of the phase shifter mode switching unit 56 in this embodiment.

The phase shifter mode switching unit 56 takes in the latitude from the satellite latitude register 78 of the azimuth/elevation angle input unit 54,
This circuit executes threshold judgment based on this latitude, determines the tracking mode, and switches the operation.

[0149] In order to realize such switching, the phase shifter mode switching section 56 has a tracking mode determining means 94. The tracking mode determining means 94 determines the tracking mode based on the latitude information stored in the latitude register 78. That is, if this latitude is greater than or equal to a predetermined value,
A tracking mode switching signal having a value indicating a high latitude area is generated and output. Conversely, if it is less than this predetermined value, a tracking mode switching signal having a value indicating that the area is in a low latitude area is output. The threshold value for such determination may be set empirically depending on the accuracy of the magnetic compass, the width of the beam, and the like. For example, it can be set to 30°. This tracking mode switching signal is supplied to the control amount calculation unit 52 as described above, and is sent to the AZ-axis control amount calculation means 72 and the EL
The control amount calculation algorithm in the axis control amount calculation means 74 is switched. That is, in the case of a tracking mode switching signal indicating that the area is in a high latitude area, the control amount calculation unit 52 selects AZ
- When the EL mount indicates that the area is in a low latitude area, the AZ-EL-XEL mount performs calculations related to vibration compensation.

The tracking mode switching signal output from the tracking mode determining means 94 is supplied to the control amount calculation unit 52 as well as tracking mode changeover switches 96 and 98. Of the two tracking mode changeover switches 96 and 98, the tracking mode changeover switch 96 takes in an azimuth input from a device such as a magnetic compass. This azimuth input is information indicating a change in the azimuth of the moving object (ship) on which the device is mounted. In the case of this embodiment, the tracking mode switch 96 is controlled by the tracking mode switching signal supplied from the tracking mode determining means 94, and when the tracking mode switching signal has a value indicating a low latitude area, the tracking mode switching signal from a magnetic compass or the like is controlled. The switch 96 is switched so that the direction input is output from the tracking mode changeover switch 96. The output of the tracking mode changeover switch 96 is supplied to the azimuth/elevation angle input section 54 and is used by the adder 90 to update the contents of the mobile object azimuth register 86.

On the other hand, the tracking mode changeover switch 98 takes in the phase shifter control amount obtained by the phase shifter control amount calculation means 76 of the control amount calculation section 52, and transmits the phase shifter control signal to the phase shifter of the array antenna 12. This is a switch that supplies power to the drive circuit 46. This switch 98 is controlled by a tracking mode switching signal. That is, when the tracking mode switching signal has a value indicating a low latitude area, the tracking mode switching switch 98 is switched to the phase shifter control amount calculation means 76 side, and as a result, the phase shifter control amount is changed to the phase shifter control amount. This will be supplied to the array antenna 12 as a control signal.

On the other hand, the phase shifter mode switching section 56 according to this embodiment includes phase switching signal generating means 100. The phase switching signal generating means 100 is a means for generating a phase switching signal having a square wave waveform, for example. The phase switching signal is supplied to a tracking mode changeover switch 98, and when the tracking mode changeover signal has a value indicating a high latitude area, it is supplied to the array antenna 12 via this switch 98 as a phase shifter signal. That is, the switch 98 is switched to the phase switching signal generation means 100 side when the tracking mode switching signal has a value indicating a high latitude area.

The phase switching signal is sent to the phase shifter drive circuit 46 of the array antenna 12 via the tracking mode changeover switch 98.
, the beams are switched by controlling the phase shifters 44-1 and 44-3. For example, if the beam before switching to the tracking mode is beam 4, the beam alternates with the adjacent beam 3 or beam 5. For example, when the phase switching signal is a square wave signal, beam 3 and beam 4 appear alternately every half period of the square wave signal, and for example, when the phase switching signal is a ternary staircase waveform, Beams 3, 4 and 5 appear at each stage.

[0154] The phase switching signal is the tracking mode switching switch 9.
8 to the antenna 12, so that when the beams are alternately switched, the level of the signal obtained from the array antenna 12 changes in synchronization with the switching. As will be described later, the antenna output processing unit 58 takes in the received signal of the array antenna 12 and outputs a signal having a value corresponding to the level of the received signal, that is, a received level signal. The phase switching signal is supplied to the azimuth error detection means 60 to synchronously detect this received level signal, and the resulting azimuth error is supplied to the tracking mode changeover switch 96. That is, if the received level signal is synchronously detected using the phase switching signal, information regarding the received level difference obtained by beam switching is obtained, and this information is supplied to the tracking mode changeover switch 96 as the azimuth error.

The tracking mode changeover switch 96 is a switch that is switched according to the value of the tracking mode changeover signal as described above, and when the tracking mode changeover signal has a value indicating a high latitude area, the direction error detection means 60 side can be switched to In this case, the information supplied to the azimuth/elevation angle input section 54 via the tracking mode changeover switch 96 is the azimuth error obtained by synchronous detection. Therefore, in the case of a high latitude region, the moving body direction in the direction/elevation angle input section 54 is updated based on the direction error obtained by the direction error detection means 60, and accordingly, the control amount calculation section 52 is moved. The phaser control amount calculation means 76 is the array antenna 1
2, the phase shifter control amount is calculated so that the highest reception level can be obtained. That is, the phase shifter control amount calculation means 78 executes calculations related to satellite tracking, and the array antenna 12 operates accordingly.

[0156] At this time, the phase shifter control amount calculation means 76
The phase shifter control amount obtained by the above must be supplied to the array antenna 12 as a phase shifter control signal. Therefore, the tracking mode changeover switch 98 performs a phase shift after a certain period of time has elapsed since the value of the tracking mode changeover signal output from the tracking mode determining means 94 changes from a value indicating a low latitude area to a value indicating a high latitude area. device control amount calculation means 78 side.

(3.5) Antenna output processing unit FIG. 12 shows the antenna output processing unit 5 used in this embodiment.
8 configurations are shown.

[0158] Antenna output processing section 58 shown in this figure
has a receiver 102 and reception level signal generation means 104. That is, its basic configuration is almost the same as the antenna output processing section described as a component of the first embodiment in Japanese Patent Application No. 3-40297, which was previously proposed by the applicant of the present application. Therefore, its detailed operation will not be explained here. In addition, in this figure, Japanese Patent Application No. 3-4029
Unlike No. 7, the step track control circuit is omitted. The step track control circuit has a satellite elevation angle register 8.
4 and a moving object orientation register 86 to supply the step track angle. Regarding its basic structure, for example, Japanese Patent Application No. 2-175014, Japanese Patent Application No. 2-240413
Since it has already been disclosed in the applicant's previous proposal such as No. 1, it will be omitted here.

(4) Operation of the first embodiment Next, the operation of the present embodiment having the above circuit configuration will be explained.

The operation of this embodiment is as follows: The azimuth/elevation angle input section 5
The operation differs depending on whether the position of the moving body input in step 4 indicates a high latitude area or a low latitude area. Therefore, here, the case of a high latitude area and the case of a low latitude area will be explained separately, and the switching operation between the two will be explained.

It is assumed that the satellite to be tracked is a geostationary satellite orbiting above the earth's equator and stationary with respect to the latitude and longitude of the earth.

(4.1) Operation direction in low latitude areas
If the position of the moving body input to the elevation angle input unit 54 belongs to a low latitude area, that is, if the latitude stored in the latitude register 78 is less than a predetermined value, the tracking of the phase shifter mode switching unit 56 Mode determining means 94 outputs a tracking mode switching signal having a value indicating that the area is a low latitude area. This tracking mode switching signal is transmitted to the tracking mode switching switch 9.
6 and 98, the switches 96 and 98 are
Magnetic compass side and phase shifter control amount calculation means 76, respectively
thrown to the side.

[0163] Therefore, in this case, the azimuth/elevation angle input section 54
In addition to the above-mentioned position of the moving object, azimuth input from a device such as a magnetic compass is supplied to the . The azimuth input related to a magnetic compass or the like is information indicating an increment in the azimuth of the moving body. A magnetic compass is known as a device that is cheaper than, for example, a gyro compass, but its accuracy is lower than that of a gyro compass in high latitude areas. However, in this case, since the region is at a low latitude, a certain level of accuracy is maintained for the azimuth input supplied to the azimuth/elevation angle input section 54 via the tracking mode changeover switch 96.

In the azimuth/elevation angle input section 54, the input moving object position is input to the latitude register 78 and the longitude register 8.
Each is stored in 0. The latitude and longitude related to this position are input to the satellite azimuth/elevation angle calculation means 82, and the satellite azimuth/elevation angle calculation means 82 calculates the elevation angle and absolute azimuth of the satellite based on the latitude and longitude based on the known satellite position.

Among the obtained information, the elevation angle of the satellite is supplied to the satellite elevation angle register 84, and is output to the control amount calculation section 52 while being corrected by the step track angle as necessary. On the other hand, the absolute azimuth of the satellite is supplied to an adder 92, which subtracts the moving object azimuth from the absolute azimuth of the satellite, and supplies the result to the satellite azimuth register 88 as a relative azimuth.

The moving object orientation is information stored in the moving object orientation register 86. The mobile object orientation register 86 stores the mobile object orientation under adjustment by the step track control circuit in predetermined cases. Mobile direction register 8
The information to be stored in the tracking mode changeover switch 96 is information that is successively corrected and updated by the direction input obtained from a magnetic compass or the like via the tracking mode changeover switch 96. That is, an azimuth input from a magnetic compass or the like is supplied to an adder 90 disposed before the moving object azimuth register 86, and the moving object azimuth register 86 is sequentially updated based on this azimuth input.

[0167] The satellite elevation angle and the relative orientation of the satellite stored in the satellite elevation angle register 84 and the satellite azimuth register 88 are both supplied to the control amount calculation unit 52. In this case, AZ
The axis control amount calculation means 72, the EL axis control amount calculation means 74, and the phase shifter control amount calculation means 76 execute calculations related to satellite tracking based on the satellite elevation angle and the relative orientation of the satellite. Also,
The control amount calculation means 72, 74, and 76 take in the output of the swing detection means 62, and control amount calculations related to swing compensation are executed based on the outputs.

This control amount calculation is performed according to the algorithms shown in equations (9) to (15) described above. That is, in this case, the tracking mode switching signal generated by the tracking mode determining means 94 has a value indicating a low latitude,
Since this signal is supplied to the AZ-axis control amount calculation means 72 and the EL-axis control amount calculation means 74, these control means 72 and 74 calculate the control amount using the algorithm related to the AZ-EL-XEL mount. You can know good things. Therefore, the AZ-axis control amount calculation means 72 and the EL-axis control amount calculation means 74 operate according to the tracking mode switching signal.
Calculation is performed using an algorithm related to Z-EL-XEL mount.

The control amount thus determined is supplied to the mechanical shaft drive section 50 or the phase shifter mode switching section 56. What is supplied to the mechanical axis drive section 50 are the AZ-axis control amount and the EL-axis control amount. In the mechanical axis drive unit 50, the motors 30 and 18 are driven based on the AZ-axis control amount and the EL-axis control amount, and the azimuth axis 26 and the elevation axis 14 are rotated. That is, drive control of these mechanical axes is executed.

[0170] Of the control variables found in the control amount calculation section 52, the phase shifter control amount found by the phase shifter control amount calculation means 76 is selected by the tracking mode changeover switch 98 included in the phase shifter mode switching section 56. Supplied. in this case,
Since the tracking mode changeover switch 98 is turned to the phase shifter control amount calculation means 76 side by the tracking mode changeover signal indicating a low latitude area, the phase shifter control amount is used as a phase shifter control signal to shift the array antenna 12. It will be supplied to the phaser drive circuit 46. The phase shifter drive circuit 46 controls the phase shifters 44-1 and 44-3 according to the phase shifter control signal, and selects and realizes a beam according to the value of the phase shifter control signal. As a result, the XEL axis is realized as an electronic axis.

(4.2) Operation direction in high latitude areas
When the position of the moving object input to the elevation angle input section 54 indicates a high latitude area, that is, when the latitude stored in the latitude register 78 is a predetermined latitude or higher, the following operation is performed.

That is, the tracking mode determining means 94 generates and outputs a tracking mode switching signal having a value indicating a high latitude area in response to the latitude taken in from the latitude register 78 being equal to or higher than a predetermined latitude. This tracking mode switching signal is transmitted to the tracking mode switching switches 96 and 98 to the azimuth error detection means 60 side and to the phase switching signal generation means 100, respectively.
Switch to the side.

Then, instead of the phase shifter control amount calculated by the phase shifter control amount calculation means 76, the phase switching signal generated by the phase switching signal generation means 100 is used as the phase shifter control signal via the switch 98. It will be supplied to the phase shifter drive circuit 46. The phase shifter drive circuit 46 alternately switches the beam directivity characteristics of the array antenna 12 based on the phase switching signal. When the beam directivity characteristics of the array antenna 12 are alternately switched, the output of the combiner 48 changes alternately, and therefore the value of the reception level signal output from the reception level signal generation means 104 of the antenna output processing section 58 also changes. Vary alternately. This variation is a variation synchronized with the phase switching signal. The azimuth error detection means 60 performs synchronous detection of the received level signal using the phase switching signal to obtain information regarding the received level difference. Therefore, this information is information indicating the azimuth error of the array antenna 12, and has content corresponding to azimuth input obtained by a magnetic compass or the like when the moving body turns. Since the orientation error detection means 60 is connected to the adder 90 by switching the switch 96 mentioned above, the orientation of the moving body is corrected by the orientation error obtained by the orientation error detection means 60, and the relative orientation of the satellite is corrected. be done. Then, the relative orientation of the satellite obtained through this correction is supplied from the satellite orientation register 88 to the control amount calculation unit 52. At this time, the AZ-axis control amount calculation means 72 and the EL-axis control amount calculation means 74 are supplied with a tracking mode switching signal indicating that the area is in a high latitude area, and these control amount calculation means 72 and 74 are Control amount calculation based on the above-mentioned equations (1) to (8) is started. That is, the AZ-axis control amount calculation means 72 and the EL-axis control amount calculation means 74 each calculate the control amount according to the algorithm related to the AZ-EL mount.

In this case, the phase shifter control amount calculation means 76 is
The satellite elevation angle and the relative orientation of the satellite are taken in from the satellite elevation angle register 84 and the satellite azimuth register 88, and the phase shifter control amount is determined to perform the satellite tracking operation. Therefore,
In this case, tracking of the satellite will be performed by controlling the amount of phase shift of the array antenna 12.

(5) Effects of the first embodiment With this embodiment having such a configuration, it is possible to eliminate errors in azimuth input in high latitude areas and perform highly accurate tracking. That is, in a high latitude area, a tracking mode switching signal indicating a high latitude is output from the tracking mode determining means 94, and the azimuth error obtained by the azimuth error detection means 60 is input to the adder 90 instead of the azimuth input obtained from a device such as a magnetic compass. Therefore, the use of outputs such as magnetic compasses will be discontinued. In high latitude areas, it is not possible to obtain a highly accurate heading with a magnetic compass, which is an inexpensive device, but in this example, the heading error obtained by synchronous detection is used in such cases, so the accuracy can be improved. It becomes possible to secure the As a result, even a small ship or the like that is not equipped with a high-precision device such as a gyro compass can perform excellent satellite tracking in high latitude areas.

Furthermore, this embodiment is particularly effective when the satellite to be tracked is a geostationary satellite. Also, GPS
The azimuth and elevation angle of the satellite can be determined based on the position of the moving body inputted from the above, and each control amount can be calculated accordingly.

Furthermore, in this embodiment, the structure of the array antenna 12 is simple, and the device can be constructed at low cost. That is, since the phase shifter 44 is not provided for each antenna element 10, the phase shifter 44 is not provided for each antenna element 10.
The arrangement and the circuit configuration related to its control are simplified, and the cost of the device is reduced. Furthermore, since the array antenna is smaller than a parabolic antenna or the like, it is possible to downsize the device from this point of view as well. Furthermore, in this example,
Since the phase shifter 44 is provided only in the end row of the antenna element 10 arrangement, switching of beam directivity characteristics can be realized with a relatively economical configuration.

Furthermore, the array antenna 12 is attached to the supporting legs 28.
Since the access hatch 40 is eccentrically supported on the bottom surface of the radome 38, the access hatch 40 can be provided at a position almost directly below the array antenna 12, and even a small antenna device can be realized with high maintainability.

(6) The circuit configuration of the second embodiment is shown in FIG.
The overall circuit configuration of a swing-compensated antenna device according to a second embodiment of the present invention is shown.

The biggest difference between this embodiment and the first embodiment described above is that the azimuth/elevation angle input section 54 does not input the position of the moving body from GPS or the like, but instead uses search control to determine the relative azimuth of the satellite. . Array antenna 12 in this embodiment
, the mechanical shaft drive unit 50, the azimuth error detection means 60, and the swing detection means 62 have completely the same configuration as in the first embodiment, and therefore their explanation will be omitted.

(6.1) Azimuth/elevation angle input section In FIG.
The configuration of the azimuth/elevation angle input section 54 in this embodiment is shown.

The azimuth/elevation angle input section 54 shown in this figure is similar to the azimuth/elevation angle input section 54 in the first embodiment.
It has a satellite elevation angle register 84, a satellite azimuth register 88, and an adder 90. However, in this embodiment, the satellite orientation register 88 is controlled by step tracking as necessary. This is because the update of the satellite's relative orientation in this embodiment is not an update of the mobile object's orientation, but a direct update of the satellite's relative orientation. That is, in the azimuth/elevation angle input section according to this embodiment, the mobile object azimuth register 86 is not provided, and furthermore, information regarding the absolute azimuth of the satellite is not generated.

Therefore, in this embodiment, the contents of the satellite azimuth register 88 are sequentially updated by addition with the azimuth error or compass input by the adder 90. on the other hand,
The satellite elevation angle register 84 and the satellite azimuth register 88 include:
The elevation angle of the satellite and the relative azimuth of the satellite obtained through search control are stored. For this reason, in this embodiment, a search control means 106 is provided.

The search control means 106 executes search control in response to turning on the power to the device, a search command from the outside, and a carrier detection signal (CD) generated by a demodulator of the antenna output processing section 58, which will be described later. do. The configuration of this search control means 106 is an application of, for example, the configuration of the azimuth search control circuit shown in Japanese Patent Application No. 2-240413, which was previously proposed by the applicant. In this embodiment, it is necessary to perform search control for both the elevation angle of the satellite and the relative azimuth of the satellite.

Therefore, in this embodiment, the relative orientation of the satellite is determined without using the latitude and longitude of the position of the moving object.

(6.2) Other differences in circuit configuration Next,
Differences in the circuit configurations of each section corresponding to such differences in the configuration of the azimuth/elevation angle input section 54 will be explained.

FIG. 15 shows the configuration of the phase shifter mode switching section 56 in this embodiment, and FIG. 16 shows the configuration of the control amount calculation section 52.
The configuration of the antenna output control section 58 is shown in FIG. 17, and the configuration of the antenna output control section 58 is shown in FIG.

First, unlike the phase shifter mode switching unit 56 according to the first embodiment, the phase shifter mode switching unit 56 shown in FIG. 15 uses the satellite elevation angle instead of the latitude stored in the latitude register 78. The satellite elevation angle stored in register 84 is input. This satellite elevation angle is input to the tracking mode determining means 94. The tracking mode determining means 94 in this embodiment executes a threshold judgment on the satellite elevation angle, and based on the result of this threshold judgment, a tracking mode switching signal indicating whether the satellite is in a high elevation angle area or a low elevation angle area. Generate and output. In addition, tracking mode changeover switches 96 and 9
8 is switched accordingly.

In this embodiment, the tracking mode changeover switches 96 and 98 are switched to the upper side of the diagram, ie, to the magnetic compass side and the phase shifter control amount calculation means 76 side in high elevation angle areas.

Therefore, in this embodiment, the azimuth input from a magnetic compass or the like is input to the adder 90 of the azimuth/elevation angle input section 54 in a high elevation angle area. Further, the phase shifter control amount calculated by the phase shifter control amount calculation means 76 is
The signal is supplied to the phase shifter drive circuit 46 of the array antenna 12 as a phase shifter control signal.

On the other hand, if the tracking mode switching signal is a signal indicating a low elevation angle area, the tracking mode switching signal 96
and 98 are switched to the lower side of the figure, and while the phase switching signal output from the phase switching signal generating means 100 is supplied to the phase shifter drive circuit 46 of the array antenna 12 as a phase shifter control signal, the phase switching signal is switched to the lower side of the figure. Array antenna 1 by signal
The reception level signal obtained according to the output of 2 is synchronously detected by the azimuth detecting means 60, and the azimuth error obtained by this synchronous detection is supplied to the adder 90 via the tracking mode changeover switch 96.

FIG. 16 shows the configuration of the control amount calculating section 52 in this embodiment. As shown in this figure, in this embodiment, the tracking mode switching signal is not supplied to the AZ-axis control amount calculation means 72 and the EL-axis control amount calculation means 74. In the first embodiment described above, the AZ-axis control amount calculation means 72 and the EL-axis control amount calculation means 74 used different calculation algorithms depending on the latitude, but in this embodiment, the calculation algorithms differ based on the elevation angle. In order to achieve this, the AZ-axis control amount calculation means 72 and the EL-axis control amount calculation means 74 automatically switch their operations based on the satellite elevation angle taken in from the satellite elevation angle register 84. In this case, when the elevation angle of the satellite is low, the control amount calculation algorithm for high latitude areas in the first embodiment is adopted, and when the elevation angle is high, the control amount calculation algorithm for low latitude areas is adopted.

FIG. 17 shows the configuration of the antenna output processing section 58 in this embodiment. The antenna output processing section 58 in this embodiment further includes the receiver 102.
It is equipped with a demodulator 108 that takes in the output of. Demodulator 1
08 is a circuit that takes in the IF signal that is the output of the receiver 102 and generates a carrier detection signal (CD). The carrier detection operation performed in the demodulator 108 is one of the basic operations in a general demodulator, and many methods have been developed or put into practical use, such as a method using PLL, for example. A carrier detection signal (CD), which is a result of carrier detection, is a signal indicating whether a desired signal is received at a certain level or higher, and the demodulator 108 supplies this to the search control means 106 and performs the search. Provided as information that is the basis of control.

(7) Operation of Second Embodiment Next, the operation of this embodiment will be explained, focusing in particular on the differences in operation from the first embodiment.

In this embodiment, when the power is turned on,
A search is executed by the search control means 106. That is, the search control means 106 generates a search control angle and supplies it to the satellite elevation angle registers 84 and 88, respectively, as the satellite elevation angle or relative azimuth of the satellite. When the search control means 106 and the search angle are supplied to the satellite elevation angle register 84 and the satellite azimuth register 88, the control amount calculation unit 52 reads the elevation angle and relative azimuth of the satellite from the satellite elevation angle register 84 and the satellite azimuth register 88, and performs tracking. The control amount related to is calculated. Based on the control amount obtained as a result, the mechanical shaft drive section 50 is controlled, and the azimuth axis 26 and the elevation axis 14 are rotated. Further, the phase shifter control amount calculated by the phase shifter control amount calculation means 76 is supplied as a phase shifter control signal to the phase shifter drive circuit 46 of the array antenna 12 via the tracking mode changeover switch 98, and the XEL axis A search related to this is executed.

The output obtained from the array antenna 12 during the search is supplied to the search control means 106 as a carrier detection signal (CD) via the receiver 102 and the demodulator 108. The search control means 106 executes the search until a predetermined CD is obtained, and then shifts to normal operation.

In normal operation, the satellite elevation angle stored in the satellite elevation angle register 84 is taken into the tracking mode determining means 94 of the phase shifter mode switching section 56. The tracking mode determining means 94 determines whether the satellite elevation angle is greater than or equal to a predetermined elevation angle, and determines the tracking mode. The tracking mode determining means 94 outputs a tracking mode switching signal having a value corresponding to the determined tracking mode and supplies it to the tracking mode changeover switches 96 and 98. At this time, if the satellite elevation angle is higher than the predetermined elevation angle, it can be assumed that the moving object exists in a high elevation angle area, so the tracking mode changeover switches 96 and 98 are switched to the upper side in the figure. As a result, the azimuth input related to the magnetic compass or the like is supplied to the adder 90 via the tracking mode changeover switch 96.

When an azimuth input is supplied to the adder 90, this input is added to the contents of the satellite azimuth register 88, thereby updating the contents of the satellite azimuth register 88, ie, the relative azimuth of the satellite. The updated relative azimuth and satellite elevation angle stored in the satellite elevation angle register 84 are supplied to the control amount calculation unit 52, where the control amount related to satellite tracking is calculated. At this time, the control amount calculation unit 52 is supplied with roll and pitch information related to the swing of the moving object from the swing detecting means 62, and the control amount calculation unit 52 is supplied with roll and pitch information related to the swing of the moving body, and the swing is determined by the algorithm shown in the above-mentioned equations (9) to (15). A control amount related to compensation is calculated. That is,
In this case, the control amount related to the AZ-EL-XEL mount is determined.

The control amount obtained in this way is AZ
The shaft and EL shaft are supplied to a mechanical shaft drive section 50,
The XEL axis is supplied to the phase shifter drive circuit 46 of the array antenna 12 via the tracking mode changeover switch 98. At this time, the tracking mode switching signal generated by the tracking mode determining means 94 is transmitted to the tracking mode switching switch 98.
By being supplied to the tracking mode changeover switch 98
is switched to the phase shifter control amount calculation means 76 side.

[0200] Therefore, in high elevation angle areas, tracking is performed based on the azimuth input from a magnetic compass, etc., and the AZ-
Swing compensation is performed by the EL-XEL mount.

Next, consider the case where the satellite elevation angle, which is the content of the satellite elevation angle register 84, becomes less than or equal to a predetermined elevation angle. In this case, the tracking mode determining means 94 generates a tracking mode switching signal indicating that the area is a low elevation angle area. In response to this, the tracking mode changeover switches 96 and 98 are switched to the lower side of the figure. That is, the output of the azimuth error detection means 60 is supplied to the adder 90, and the output of the azimuth error detection means 60 is supplied to the adder 90.
A zero output is provided to the phase shifter drive circuit 46. Then,
The phase shifters 44-1 and 44-3 are controlled by the phase switching signal output from the phase switching signal generating means 100, and the beams are alternately switched. The array antenna 12 output corresponding to the alternately switched beams is supplied to the antenna output processing section 58, and a reception level signal whose value fluctuates in synchronization with the phase switching signal is generated. This reception level signal is synchronously detected by the phase switching signal in the azimuth error detection means 60, and the azimuth error detected at this time is sent to the adder 9 via the tracking mode changeover switch 96.
0.

That is, the relative orientation of the satellite, which is the content of the satellite orientation register 88, is updated based on the orientation error.

The relative azimuth thus obtained and the satellite elevation angle stored in the satellite elevation angle register 84 are supplied to the control amount calculation section 52 as in the case of high elevation angle areas. However, since the satellite elevation angle stored in the satellite elevation angle register 84 is greater than or equal to a predetermined threshold, the AZ-axis control amount calculation means 72 and the EL-axis control amount calculation means 74 use a calculation algorithm different from that for high elevation angle areas. In other words, the corresponding control amount is calculated using the AZ-EL mount control amount calculation algorithm according to the above-mentioned equations (1) to (8). Therefore, in this embodiment, A
The Z-EL mount performs rocking compensation, and the XEL axis performs satellite tracking.

(8) Effects of Second Embodiment Therefore, according to this embodiment, satellite tracking and swing compensation can be performed without using a moving body position input from a GPS or the like. Further, unlike the first embodiment, this embodiment is particularly effective even when the satellite is not a geostationary satellite. The above-described first embodiment switches the tracking mode depending on the latitude of the moving body, and is therefore effective only for geostationary satellites. In this embodiment, since the determination is made directly based on the elevation angle of the satellite, it can be effectively applied even when the satellite is not a geostationary satellite.

(9) Others In the above description, a magnetic compass or the like is assumed as a device related to direction input, but this does not have to be a magnetic compass. However, a magnetic compass is more advantageous in terms of reducing the cost of the device. Also, there is no mention of supporting the radome 38, but this is a normal method,
For example, it may be fixed on the deck of a ship using a support. Further, the support structure disclosed in Utility Model Application No. 2-89713 can be applied. Further, as the structure of the array antenna 12, the checkered element array structure described in Japanese Patent Application No. 3-40297 can be used. When such a structure is used, control related to the XEL axis can be made easier, and control can be simplified by using the AZ axis only for tracking in the satellite direction. Furthermore, the array antenna 12 may be supported by the EL axis on the side surface of the radome 38, and in this case, the device configuration becomes even more compact.

[0206]

[Effect of the invention] As explained above, claim 1 of the present invention
According to
Since the swing compensation is performed using the Z-EL-XEL mount, a highly accurate and economical device can be obtained while eliminating the singularity associated with the AZ-EL mount in low latitude areas.

According to claim 2, in a low elevation angle area, AZ-
The EL mount performs rocking compensation, the XEL axis performs tracking,
On the other hand, in high latitude areas, since the AZ-EL-XEL mount is used to perform vibration compensation, as in claim 1,
It is possible to eliminate singularities related to the AZ-EL mount and to configure an inexpensive device while ensuring tracking accuracy. Further, according to claim 3 of the present invention, in low latitude areas or high elevation angle areas, the direction change taken in from a device such as a magnetic compass causes the antenna to be detected by synchronous detection of the received level signal in high latitude areas or low elevation angle areas. Since the antenna is controlled by correcting the relative orientation of the satellite based on the orientation error, the device can be constructed using an inexpensive magnetic compass instead of a relatively expensive gyro compass as the orientation change input means.

According to claim 4, when the AZ-EL-XEL mount performs rocking compensation in a low latitude region or a high elevation angle region, the AZ axis is rotated by the relative azimuth of the satellite. The azimuth control can be easily performed, and the device configuration and algorithm related to the control can be simplified.

According to claim 5, since the relative orientation of the satellite is determined using the absolute orientation and the moving object orientation, when the absolute orientation of the satellite is known, this is used to track the satellite and compensate for the oscillation. It becomes possible to execute.

[0210] According to claim 6, since the elevation angle and absolute azimuth of the satellite are determined using the latitude and longitude of the moving body, tracking of the satellite and swing compensation can be performed using a device such as GPS. Can be done.

According to claim 7, since the correction of the relative orientation of the satellite is performed as the correction of the orientation of the moving body, it is possible to construct an apparatus using simple means.

According to claim 8, since the relative orientation of the satellite is searched by the search control means, the satellite tracking and oscillation compensation can be performed with a simple device configuration without using information such as the absolute orientation of the satellite. can be executed.

According to claim 9, the antenna is constructed as a so-called array antenna, and the beam directivity characteristics are switched by controlling the amount of phase shift, so that the device can be constructed at low cost with an antenna having a simple construction.

According to claim 10, since the antenna is eccentrically supported on the bottom surface of the radome by the legs, it is possible to provide an access hatch directly below the antenna.
Improves maintainability of equipment.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the actual configuration of a swing-compensated antenna according to an embodiment of the present invention.

FIG. 2 is a diagram showing the axial configuration of the antenna according to this embodiment.

FIG. 3 is a schematic plan view showing the circuit configuration of an array antenna used in this example.

FIG. 4 is an antenna gain characteristic diagram showing an example of beam control of the array antenna shown in FIG. 3;

FIG. 5 is a block diagram showing the overall circuit configuration of a swing-compensated antenna device according to a first embodiment of the present invention.

FIG. 6 is a block diagram showing the configuration of a mechanical shaft drive section in this embodiment.

FIG. 7 is a block diagram showing the configuration of a control amount calculation section in this embodiment.

FIG. 8 is a diagram showing a polar coordinate system used in the control amount calculation section of this embodiment.

FIG. 9 is a diagram illustrating the concept of coordinate transformation performed in the control amount calculation section of this embodiment.

FIG. 10 is a block diagram showing the configuration of an azimuth/elevation angle input section in this embodiment.

FIG. 11 is a block diagram showing the configuration of a phase shifter mode switching section in this embodiment.

FIG. 12 is a block diagram showing the configuration of an antenna output processing section in this embodiment.

FIG. 13 is a block diagram showing the overall circuit configuration of a swing-compensated antenna device according to a second embodiment of the present invention.

FIG. 14 is a block diagram showing the configuration of an azimuth/elevation angle input section in this embodiment.

FIG. 15 is a block diagram showing the configuration of a phase shifter mode switching section in this embodiment.

FIG. 16 is a block diagram showing the configuration of a control amount calculation section in this embodiment.

FIG. 17 is a block diagram showing the configuration of an antenna output processing section in this embodiment.

[Explanation of symbols]

10 Antenna element 12 Array antenna 14 Elevation axis 18 Elevation axis motor 26 Azimuth axis 28 Support leg 30 Azimuth axis motor 44-1, 44-3 Phase shifter 50 Mechanical axis drive section 52 Controlled amount calculation section 54 Azimuth/elevation angle input section 56 Phase shifter mode switching section 58 Antenna output processing section 60 Direction error detection means 62 Oscillation detection means 64 AZ-axis control means 66 EL-axis control means 72 AZ-axis control amount calculation means 74 EL-axis control amount calculation means 76 Phase shifter control Quantity calculating means 78 Latitude register 80 Longitude register 82 Satellite azimuth/elevation angle calculating means 84 Satellite elevation angle register 86 Mobile object azimuth register 88 Satellite azimuth register 90 Adder 92 Adder 94 Tracking mode determining means 96, 98 Tracking mode changeover switch 100 Phase switching signal Generating means 102 Receiver 104 Reception level signal generating means 106 Search control means AZ Azimuth EL Elevation XEL Cross elevation S (x, y, z) Satellite position coordinate φ Satellite relative azimuth φc Azimuth axis control angle η Elevation axis control Angle p Pitch angle r Roll angle

Claims (10)

[Claims] Claim 1: An antenna having predetermined beam directivity characteristics, an azimuth axis that is a mechanical axis related to azimuth, an elevation axis that is a mechanical axis related to elevation, and a plane perpendicular to the rotation plane of the elevation axis. a cross-elevation axis that is an electronic axis related to the angle of a swing compensation means for compensating for a swing component that is a deviation of the antenna caused by the
In a swing compensation type antenna device having a swing compensation type antenna device, swing compensation is performed using an azimuth axis and an elevation axis in a high latitude region where a moving object is located at a predetermined latitude or higher.
A high latitude region control means is provided for controlling the tracking control means and the swing compensation means so that the satellite is tracked by the cross-elevation axis.
A swing-compensated antenna device characterized by tracking a satellite using an EL-electronic XEL mount. Claim 2: An antenna having predetermined beam directivity characteristics, an azimuth axis that is a mechanical axis related to azimuth, an elevation axis that is a mechanical axis related to elevation, and a plane perpendicular to the rotation plane of the elevation axis. a cross-elevation axis that is an electronic axis related to the angle of a swing compensation means for compensating for a swing component that is a deviation of the antenna caused by the
In a swing-compensated antenna device having a tilt angle, in a low elevation area where the elevation angle of the satellite is less than a predetermined angle, swing compensation is performed using the azimuth axis and the elevation axis, and satellite tracking is performed using the cross-elevation axis. AZ-EL is equipped with a low elevation angle area control means for controlling the tracking control means and the swing compensation means.
A swing compensation type antenna device characterized in that a satellite is tracked by a mount, and in other areas by an AZ-EL-electronic XEL mount. 3. In the swing-compensated antenna device according to claim 1 or 2, an azimuth error of the antenna is detected by synchronously detecting a reception level signal representing the reception level of the antenna with a signal related to switching of beam directivity characteristics. azimuth error detection means for detecting the azimuth error; and azimuth change input means for inputting the azimuth change of the moving body from a device such as a magnetic compass; A swing-compensated antenna device, characterized in that the relative orientation of the satellite is corrected in accordance with the change in orientation in the region. 4. In the swing-compensated antenna device according to claim 1 or 2, the tracking control means rotates the azimuth axis by the relative azimuth of the satellite in regions other than high latitude regions or low elevation angle regions, and A swing-compensated antenna device characterized by controlling orientation. 5. The swing-compensated antenna device according to claim 3, further comprising: a satellite azimuth/elevation angle calculation means for calculating the elevation angle and absolute azimuth of the satellite; A swing-compensated antenna device comprising: means for determining an azimuth. 6. The swing-compensated antenna device according to claim 5, further comprising means for inputting the latitude and longitude of the moving body;
1. A swing-compensated antenna device, wherein the satellite azimuth and elevation calculation means calculates the elevation angle and absolute azimuth of the satellite from a known satellite orbit based on the latitude and longitude of the moving object. 7. The swing-compensated antenna device according to claim 6, wherein the correction of the relative orientation of the satellite by the tracking control means comprises:
A swing-compensated antenna device characterized in that the correction is performed as a correction of the orientation of a moving object. 8. The swing-compensated antenna device according to claim 3, further comprising search control means for causing the antenna to search for the relative orientation of the satellite. 9. The swing-compensated antenna device according to claim 1 or 2, wherein the antenna has 2 to 3 rows N (N is a natural number) with the beam switching direction of the cross-elevation axis as a row.
provided for antenna elements arranged in columns and at least two rows arranged at the ends in the antenna element array,
A swing-compensated antenna device comprising: a plurality of phase shifters that shift the phase of a received signal in a corresponding row by an amount corresponding to a cross-elevation axis control amount. 10. The swing-compensated antenna device according to claim 9, comprising: a bottomed bowl-shaped radome that covers the antenna; and legs that eccentrically support the antenna on the bottom surface of the radome, and the antenna device includes a radome that is substantially directly below the antenna on the bottom surface of the radome. A swing-compensated antenna device characterized in that an access hatch opens at a certain position.