JPH10335917A - Triaxial controller for directional antenna - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce target directional errors, especially a bearing-tracking error by accurately estimating a directional tracking error which occurs as following the delay of a servo control system and a residual error of step track, improving the quality of an error signal for controlling an Az-axis and controlling the Az-axis by using an error signal whose quality is improved. SOLUTION: A parabolic antenna 16 is supported on a traveling body 26, which pitches and rolls such as a ship with a mount that has an Az-axis 10, an X-axis 12 and a Y-axis 14. A triaxial arithmetic control circuit 40 generates error signals for controls Δϕxtd, Δθx and Δθy with roll rddet, pitch pddet, traveling body bearing ϕg from rolling and pitching detectors 54 and 56, various navigation instruments and compass or the like which are mounted on the body 26, a receiving signal level and a synchronization detection signal. In particular, it generates an Az-error signal Δϕxtd, based on the bearing ϕg. This enables executing good tracking, even under a realistic environment in which the relative bearing of a target fluctuates dynamically and to improve a target tracking error.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a directional antenna device for supporting a directional antenna with an Az-XY mount, for example, a directional antenna device for INMARSAT. More specifically, the present invention provides a directional antenna with a target, for example, while stabilizing the directional antenna against the tilt of a moving object such as a ship, by rotating around the Az axis, the X axis and the Y axis. The present invention relates to a three-axis control device for a directional antenna device that tracks an artificial satellite.

[0002]

2. Description of the Related Art In order to continuously receive a signal from a target with a directional antenna mounted on a shaking moving body, it is necessary to tilt the moving body in accordance with the relative movement of the moving body with respect to the target. The beam direction of the directional antenna may be changed according to the above. In order to make this possible, the directional antenna is usually supported on the moving object by an antenna mount (also called a pedestal), which generally has a plurality of mechanical axes. The direction of the beam of the directional antenna can be changed by appropriately rotating the plurality of mechanical axes. Therefore, the position of the target (azimuth and elevation), the traveling direction and the tilt angle (roll angle and pitch angle) of the moving body, the angular position of each machine axis, etc. are input, and rotation is given to each machine axis according to these. Thereby, the beam of the directional antenna can be continuously directed in a desired direction regardless of the inclination of the moving body (“stabilization” of the directional antenna with respect to the inclination of the moving body), and regardless of the movement or inclination of the moving body. The beam of the directional antenna can be directed to the target ("tracking" of the target by the directional antenna).

The Az-XY mount is an antenna mount having a smaller number of mechanical shafts than the conventionally used XY-Az-El mount, and therefore has a simple and compact mechanism and can be realized at low cost. The Az-XY mount is an Az (Azimu) mounted on the moving body so as to face vertically upward when the moving body is not tilted.
th) axis, an X axis arranged on the Az axis so as to be horizontal when the moving body is not tilted, and a Y axis arranged on the X axis so as to be orthogonal to the X axis and supporting a directional antenna. Machine shaft. When using the Az-XY mount, roughly, the azimuth tracking of the target is the Az axis, the elevation tracking and the stabilization for the pitch angle are the Y axis, and the stabilization for the roll angle is the rotation of the X axis. And execute. El axis is related to elevation angle
(Elevation) axis, and the X axis orthogonal thereto may be called a cross El axis. Following document Harr
ies et al., SR145 and SR150 are examples of prior art literature on Az-XY mounts.

[0004] Harries et al .: "Naval Satellite Comm
unications Terminals ”, G. Harriesand JWHeaviside,
IEE “Satellite System for Mobile Communications an
d Surveillance ”Conference Publication, No.95,1973
-03, pp.48-51. SR145: "Research Report on Automatic Transmitting and Receiving System of Weather Information by Geostationary Meteorological Satellite" Japan Shipbuilding Research Association No. 145 Study Group, Research Material No. 227, pp. 29-32 In particular, Table 4.1 on page 29 and Figure 4.11 on page 32, March 1975, SR150: "Study on Ship Operation System and Onboard Equipment Using Satellites", 150th Study Group of Japan Shipbuilding Research Association, Research Material No. 246 No. 140-150, March 1976

In these references, Harries et al. And SR14
5 is SC, a system developed by Marconi and others.
OT I and II are disclosed. For SCOT I and II, Harrie
s etal., page 49, lines 34 to 38 and SR145, as shown in FIG. 4.11, a sensor for detecting the inclination angles of the X axis and the Y axis was attached to a stable base on the X axis. , The control relating to the X axis and the Y axis is executed. That is, X
On a platform on the axis, an accelerometer (accelerometer, which detects the inclination angle around the platform of the gravitational acceleration to determine the inclination angle), a gyro for detecting the angular velocity, and an inclination angle around the Y axis An accelerometer for detecting and a gyro for detecting angular velocity are provided, and the inclination angle and angular velocity obtained from these are used for controlling the corresponding axis. SCOT I and II also have at least the Az axis (or trav
For erse), an automatic tracking, that is, a tracking method of driving a mechanical axis in accordance with the tracking signal so that the tracking signal transmitted from the target can be received by the mobile body is adopted. Therefore, SC
In OT I and II, a receiver for receiving a tracking signal is separately required, which limits the cost reduction. Further, if a tracking signal is blocked by an obstacle on or around the moving object (such as a mast when the moving object is a ship), the tracking operation is interrupted.

[0006] In SR150, page 140, line 8 to page 10
As described in the row, a sensor for detecting the inclination angle of the moving body is mounted on the Az axis. According to SR150, it is possible to reduce the azimuth tracking error due to the inclination of the moving object. The azimuth tracking error mentioned here means that the data on the target azimuth (horizontal plane) is not the same as the plane on which the antenna mount is provided (deck plane), but the data is obtained by the antenna. This is a target tracking error caused by using the mount, particularly for controlling the angular position of the Az axis.
This azimuth tracking error becomes apparent when the moving body has a large inclination angle. FIG. 9 shows a result of a simulation by the inventor of the present invention. According to this, when the roll angle exceeds 25 ° when the directional antenna has a low elevation angle of 5 °, the azimuth tracking error increases significantly. The horizontal axis of the figure is the relative orientation of the target with respect to the moving object in the moving object virtual horizontal coordinate system, and the vertical axis of the figure is Az in the moving object coordinate system.
This is a value obtained by subtracting the relative azimuth from the ideal value of the bearing angle of the shaft, that is, an azimuth tracking error (the definition of the coordinate system will be described later). S
In R150, a pair of tilt sensors on the Az-axis turntable detect the tilt angle of the hull around each of the X and Y axes, and the detected tilt angle is used for controlling the X and Y axes. The azimuth tracking error due to the moving object inclination is calculated based on the inclination angle detection value. Next, a yaw angle of the hull is detected by a yaw detector provided on the hull, and a value obtained by subtracting the yaw angle detection value from the azimuth tracking error is used as an Az axis control amount (Az axis control error signal). . Therefore, since the relative change of the target azimuth caused by the tilt of the moving object is included, it is considered that the azimuth tracking error is unlikely to become apparent.

However, while the azimuth tracking error due to the inclination of the moving object is an amount defined in the moving object coordinate system,
Since the yaw angle is an amount defined in the horizontal coordinate system, the physical meaning of the Az-axis control amount, which is the difference between the two, is ambiguous, and the X-axis is correctly oriented to the target direction. It seems that this is a prerequisite for deriving the azimuth tracking error due to the mobile body inclination. In reality, under the sway condition that the relative orientation of the target dynamically fluctuates, the control error of the Az-axis angular position caused by the following delay of the servo control system of the Az-axis driving motor cannot be ignored. Therefore, the quality Az axis control error signal obtained by the method described in SR150 is
The question remains whether it can be used for applications requiring high-precision tracking. That is, there is a possibility that a tracking error that cannot be ignored when evaluated by a mean square error or the like may increase.

[0008]

A first object of the Summary of the Invention The present invention, tracking servo control system lag, specific method to accurately estimate the ([Delta] [phi _xtd or [Delta] [phi _{value xth} hereinafter defined) orientation tracking errors arising as a residual error of the step track By improving the quality of the error signal for Az axis control, by controlling the Az axis using the improved error signal to reduce the target pointing error, especially the azimuth tracking error Δφ _xtd or Δφ _xth , furthermore The purpose is to improve the step track performance. A second object of the present invention is to maintain the advantage that the number of mechanical axes is smaller than that of an XY-Az-El mount by basically using a conventional Az-XY mount as a mount. It is in. A third object of the present invention is to enable quick start of tracking of a target and stabilization of an antenna even when a target position is not initially provided by combining a target search and a step track. To improve the accuracy of A fourth object of the present invention is to provide a specific method of searching for a target when the moving body is inclined.

The present invention can be understood as a control device for controlling a directional antenna, particularly a mechanical axis of an antenna mount thereof. The antenna mount to be controlled in the present invention is an Az-XY mount. In the present application, the Az-XY mount, which is the control object of the present invention, is disposed on the moving body so as to face vertically upward when the moving body is not tilted, and the Az axis is arranged so as to be horizontal when the moving body is not tilted. It is defined as a mount having the X-axis disposed above and the Y-axis disposed on the X-axis so as to be orthogonal to the X-axis. 1 and 2 show examples of an antenna mount satisfying this definition. In these figures,
Installed on the mounting surface on the moving object (such as a deck in the case of a ship)
It has an Az axis 10, an X axis 12 arranged on the Az axis 10 so as to be orthogonal to the Az axis 10, and a Y axis 14 arranged on the X axis 12 so as to be orthogonal to the X axis 12. An Az-XY mount supporting a directional antenna having a beam represented by middle A on a Y-axis 14 is described. The difference between the mount shown in FIG. 1 and the mount shown in FIG. 2 is that in the former, each structure is rotated by rotating each axis, while in the latter, each structure is rotated. This is a difference in the shaft drive mode in which the shaft itself does not rotate around the axis and only the structure around the axis rotates around the axis. In the present application, each of these shaft driving modes is expressed by the word “rotate the shaft”. Note that FIGS. 1 and 2 are only examples.

According to the present invention, there is provided a control device including at least a target position input means, a moving body direction input means, a mechanical axis angle position detecting means, a moving body inclination angle detecting means, an Az axis control means and an X axis Y axis control means. Can be grasped as In order to define and explain the functions of these means, the coordinate system and variables used in the present application are defined as shown in Tables 1 to 6. FIG. 3 schematically shows the relationship between these coordinate systems and variables. In addition,
To simplify the following description, it is assumed here that the axes are orthogonal to each other and that true north N is used as a reference azimuth in a horizontal coordinate system. It will be clear that this is merely for convenience. For example, although reference to true north in FIG 3 N, may be used magnetic north N _M instead, also, either of the coordinate system is also have a right-handed with a common origin O, may be left-handed . Further, in the following description, a variable relating to the azimuth is represented with reference to the “X □” coordinate axis of the reference coordinate system, and a variable relating to the elevation angle is represented with reference to the “X □ Y □” plane of the reference coordinate system. In addition, a coordinate system such as a horizontal true north coordinate system whose horizontal plane is horizontal is generally referred to as a “horizontal coordinate system”. In addition, in the present application, in a situation where there is no problem in understanding by those skilled in the art, the word roll is expressed as X _d- axis, X
In the sense that the shaft or mobile inclination of around X _td axis (angle), also the pitch term, Y _dh-axis, in the sense that Y _h-axis or mobile inclination of at Y _th axis (angle) use.

[0011]

[Table 1] Definition of coordinate system (a) Name Horizontal true north coordinate system X ₀ Y ₀ Z ₀ Properties Coordinate system fixed on horizontal plane Axis definition X ₀ : True north (N) direction Y ₀ : orthogonal to X ₀ And horizontal Z ₀ : orthogonal to X ₀ and Y ₀ (b) Name Moving body coordinate system X _d Y _d Z _d Properties Coordinate system fixed to moving body Definition of axis X _d : Pointing direction of moving body Y _d : Orthogonal to X _d , parallel to mounting surface Z _d : orthogonal to X _d and Y _d (c) Name Az-axis rotating base coordinate system XYZ properties Definition of coordinate system fixed to Az-axis rotating base Axis definition X: X axis 12 direction Y: direction of the Y-axis 14 Z: Az of axis 10 direction (d) nAME mobile horizontal coordinate system X _dh Y _dh Z _dh properties X _d Y _d Z _d is rotated by -r _d in X _d around, further the turn the coordinate system after rotation further around the Y _dh -p _d just-defined coordinate system axes obtained by the this rotating X _dh :-p _d axis was X _d before rotation Y _dh: − The axis that was Y _d before the _rd rotation, X _dh Y _dh plane = horizontal Z _dh = Z ₀ (e) Antenna horizontal coordinate system X _h Y _h Z _h Properties XYZ is rotated around −X by −r _x. , further the coordinate system after the rotation of the coordinate system axes obtained by rotating by further -p _y around the Y _h defined X _h :-p axis was X before _y rotation Y _h: - r axis was Y before _x rotation Z _h = Z ₀ (f) the definition of the virtual coordinate system axis relative to the orientation of the target T at the target horizontal coordinate system X _th Y _th Z _th nature horizontal plane X _th: orientation Y _th target T in the horizontal plane: (not shown) axis perpendicular to the X _th is in the horizontal plane Z _th = Z ₀

[0012]

TABLE 2 Variables roll pitch about the inclination angle of the mobile object compliant coordinate system ABSTRACT _{r d p d X d Y d} Z d X d, roll in Y _dh around pitch _{r ddet p ddet X d Y d} Z d X d , Y _dh around in the roll, pitch detection detection value _{r x p y XYZ X, Y} h around in the roll, pitch _{r xdet p ydet XYZ X, Y} h around in a roll, the detection value of the pitch r _td p _td XYZ X _td , roll and pitch around Y _th , X _td is the azimuth line of target T on the mounting surface The azimuth line orthogonal to this is called Y _td

[0013]

TABLE 3 orientation X _0d of X _d relative to the Variable name compliant surface payee phi _xdd mounting surface X _0d regarding peak direction of the moving body and relative to the X ₀ corresponding ray phi _XDH horizontal plane X ₀ on mounting surface X _dh orientation φ _g eg. Mounting surface eg. Value of φ _xdd detected on mounting surface

[0014]

TABLE 4 target T variable azimuth elevation compliant coordinate system ABSTRACT φ _th ε _th X relating to the position of ₀ Y ₀ Z ₀ if known _φ tvh ε tvh X ₀ Y ₀ when acquired at Z ₀ step track phi _tbd X _d Y _d Z _d X direction of _d was used as a reference was _{X td φ tbh X dh Y dh} Z dh X dh orientation of X _th relative to the

[0015]

TABLE 5 antenna beam variable orientation conforming coordinate system summary regarding the direction of _{A φ xbd X d Y d Z} d bearing angle phi _Xbddet the X-axis 12 X _d Y _d Z _d is detected on the mounting surface phi value of _xbd phi _XBH X _dh Y _dh Z _dh A value corresponding to φ _xbd on the horizontal plane Δφ _xtd X _d Y _d Z _d = φ _xbd −φ _tbd Azimuth tracking error on the mounting surface Δφ _xth X _dh Y _dh Z _dh = φ _xbh −φ _tbh horizontal plane Tracking error in GPS

[0016]

[Table 6] state variables and control variables Az shaft 10 X axis 12 Y axis 14 ABSTRACT phi _xbd x y angular position _φ xbddet x _det y _det angular position detection value Δφ _xtd Δθ _x Δθ _y control error signals of each machine axis

In the present invention, first, φ _th and ε _th are input by the target position input means. The target position input means can be realized by, for example, a member that holds and stores φ _th and / or ε _th given by an external keyboard operation or the like. The target position input means may also include φ _th and / or ε _th
Can be realized also by a target position searching means for searching when is unknown, and a step track means for executing trial and error tracking starting from φ _th and / or ε _th obtained by the search. The target position searching means,
Reception state of the signal from the target by the directional antenna to above a predetermined level, gradually while updating, enter the virtual value phi _TVH and / or epsilon _{tv h} as phi _th and / or epsilon _th.
Therefore, the target position (φ _tvh and / or ε _tvh ) can be known even when φ _th and / or ε _th are completely unknown. Further, step tracking means, trial and error and minutely phi _TVH and / or epsilon _TVH the phi _TVH and / or epsilon _TVH as a starting point when the reception state of the signal from the target due to the directional antenna exceeds a predetermined level While updating every corner, φ _tvh and / or ε as φ _th and / or ε _th
Enter _tvh . Therefore, φ _tvh and / or ε _tvh can be updated in a direction in which the reception quality becomes better, and the real φ _th and / or ε _th can be approached. Whether or not “the reception state of the signal from the target by the directional antenna exceeds a predetermined level” is determined by measuring the level of the reception signal of the directional antenna (or a signal obtained by amplifying or converting the signal). Threshold judgment of the value, threshold judgment of the measured value of the signal power to noise power ratio C / No of the received signal in the specific frequency band, or demodulation indicating that the demodulation unit is synchronized with the frequency, phase, etc. of the received signal It can be detected by determining the presence or absence of a synchronization signal from the unit. By executing such a search and step track even when the vehicle is tilted, even when the target position is not initially given or when the position of the target is lost for any reason, the tracking of the target and the antenna can be performed. Stabilization can be started quickly and high tracking accuracy can be realized.

Further, the mobile orientation input means (navigation device eg a gyrocompass outputs the phi _g, magnetic compass, inertial navigation systems, and radio navigation equipment, processing member for inputting a signal from such devices), phi _XDH And inputting the moving body direction data (for example, φ _xdd ) which can be regarded as or converted into the mechanical axis angle position detecting means (Az axis 10, X axis 12
And an angle sensor attached to each of the Y-axes 14, for example, a potentiometer or a processing member for inputting a signal from this type of sensor) detects φ _xbd , x, and y, and detects a moving body inclination angle detecting means (fixed to the moving body). combinations and upset detector eg vibrating gyroscope pendulum inclinometer or acceleration b meter outputs a r _d and p _d (accelerometer), the processing member for inputting a signal from such sensor) is, r _d and p _d or detecting the r _x and p _y. Accordingly, the processing shown in the following equations is executed by these three means.

[0019]

[Number 1] φ _xdd = φ _g ... mobile azimuth detection _{φ xbd} = φ xbddet ... bearing angle detected x = x _det ... X-axis 12 an angular position detecting y = y _det ... Y axis 14 an angular position detection _{r d} = r ddet ... X _d axis of the roll angle detection or r _x = r _xdet ... detected roll angle of the X-axis _{p d = p ddet · cr d} ... Y dh -axis of the pitch angle detection + roll effect removal or _{p y} = p ydet … Pitch angle detection around _Yh axis

In these equations, the variable having the subscript _det and φ _g are input values, for example, outputs of navigation devices and sensors. Also, in these equations, the progress of mobile but it is assumed to input the corresponding phi _g to phi _xdd as orientation data, data and corresponding to phi _XDH instead phi _xdd, or other data (where mobile (Limited to data indicating the azimuth directly or indirectly). For example, azimuth data of a type that generates a pulse each time the azimuth increases or decreases by 1/6 degree may be used. The type of data that can be input as moving body direction data, and what kind of conversion processing should be performed at the time of input, etc. are determined by the structure and output format of a device that provides moving body direction data (for example, a gyrocompass or navigation device). Is determined by Furthermore, what moistened with cr _d becomes coefficient expressions relating wherein p _d above, as is clear from FIG. 3, p _Ddet
Includes the impact component of r _d in, it is necessary to compensate for this. In the present application, cos is used as an operator c, sin
Is represented by an operator s and tan is represented by an operator t.

Furthermore, Az axis control means determines the phi _tbh based on phi _th and the mobile orientation data, phi _tbh, r _d and p _d or phi _xbd, based on the r _X and p _y phi _tbd or phi _XBH
Az axis control error signal indicating Δφ _xtd is generated,
By applying rotation to the Az axis in a direction that compensates for _Δφxtd based on the generated Az-axis control error signal, the beam of the directional antenna tracks the target with respect to its direction. An example of the calculation in the Az axis control means in the example of inputting φ _xdd as the moving body direction data is shown in the following equation.

[0022]

[ _Equation 2] φ _xdh = T ^-1 ｛sφ _xdd · cr _d / (c φ _xdd · cp _d −sφ _xdd · sr _d · s _{p d} )｝ φ _tbh = φ _th -φ _xdh φ _tbd = t ⁻¹ ｛sφ _tbh · cp _d / ( _{cr d · cφ tbh -sr d ·} sp d · sφ tbh)} Δφ xtd = φ xbd -φ tbd ... r d, when detecting ^{_{p d r d = s -1 (}} sp y · cr x · sφ xbd - _{sr x · sφ xbd) p d} = t -1 {(sr x · sφ xbd + sp y · cr x · cφ xbd) / (cr x · cp y)} φ xdh = t -1 {(sφ xdd · cr d ) / (Cφ _xdd · cp _d −sφ _xdd · sr _d · sp _d )｝ φ _tbh = φ _th −φ _xdh φ _xbh = t ^-1 ｛sφ _xbd · cp _y / (cr _x · cφ _xbd −sr _x · _{sp y · sφ xbd)} Δφ} xth = φ xbh -φ tbh Δφ xtd = t -1 {sΔφ xth · cp y / (cΔφ xth · cr x + sΔφ xth · sr x · sp y)} ... r x, p y When detecting

The X-axis and Y-axis control means include r _d ,
p _d, and using a r _x and p _y look or detected r _x and p _y Based on phi _xbd, generates an error signal Y axis control showing an X-axis control error signal and [Delta] [theta] _y shows the [Delta] [theta] _x By giving rotation to the X axis in a direction to compensate for Δθ _x based on the generated X axis control error signal, the directional antenna is stabilized against the movement of the moving body around the X axis, and the generated Y is generated. by applying a rotational direction to compensate for [Delta] [theta] _y in the Y-axis based on the axis control error signal, the directional antenna beam at the target mobile a and directional antenna is tracking respect to its elevation around the Y axis Stabilizes against upset. X
An example of the calculation in the axis Y-axis control means is shown in the following equation. r _x
The first two equations are not necessary in the configuration for detecting _py and py.

[0024]

[Number 3] ^{_{r x = t -1 {(sp}} d · sφ xbd + sr d ·
_{cp d · cφ xbd) / (} cr d · cp d)} p y = s -1 (sp d · cφ xbd -sr d · cp d · s
_{φ xbd) Δθ x = x +} r x Δθ y = y- (π / 2-ε th -p y)

As described above, according to the present invention, since the coordinate conversion between the moving body coordinate system and the horizontal coordinate system is performed to obtain a high-quality control error signal, the azimuth tracking error is reduced.
Further, in the present invention, the moving body direction data (for example, φ
_xdd ) based on φ _xdh obtained by calculation or fictitious
_Obtain φ _tbd or φ _tbh by simple calculation inside the moving object virtual horizontal coordinate system, and furthermore, φ for this φ _tbd or φ _tbh .
Az so that the error of _xbd or _φxbh , that is, _Δφxtd, is compensated.
The rotation is given to the shaft. Since the target tracking by the step track is performed while performing control on the Az axis based on the high-quality control control signal as described above, in the present invention, the real environment in which the relative azimuth φ _{xbd of the} target dynamically changes is performed. Good tracking can be performed even below. Also, Δθ _y
The order is generated using p _y, together with precise control in Az axis, it is possible to improve the target tracking error. According to the present invention, furthermore, since the positional relationship of the mechanical axes constituting the mount can be Az-XY mount, there is an advantage that the number of mechanical axes is smaller than that of the conventional XY-Az-El mount. Can be maintained continuously.

The present invention can be understood not only as a "control device" but also as a "control method", a "three-axis directional antenna" or the like. Rewriting to these categories will be obvious to those skilled in the art.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. Note that the coordinate system, variables, and their signs defined in the summary of the invention will be used in the following description. Also, in the following explanation,
For convenience of description, the mount shown in FIG. 1 or FIG. 2 is assumed.

FIG. 4 shows the configuration of the device according to the first embodiment of the present invention, and FIG. 5 shows the configuration of the device according to the second embodiment of the present invention. In these embodiments, a parabolic antenna 16 having beam A is used as a transmit / receive antenna for transmitting signals to and receiving signals from the target. However, an antenna other than the parabolic antenna may be used, and the antenna may be used not as a transmitting / receiving antenna but as a receiving antenna. Diplexer 18
Is a means for sharing the transmission and reception of the parabolic antenna 16, and has a function of supplying a transmission signal supplied from a transmitter (not shown) to the parabolic antenna 16 and the parabolic antenna 1.
6 has a function of supplying the received signal by the amplifier 6 to the amplification / frequency conversion circuit 20. The amplification / frequency conversion circuit 20 amplifies the received signal and converts the frequency from a radio frequency to a lower intermediate frequency. The received signal that has undergone amplification and frequency conversion is amplified by the intermediate frequency amplifier 22 and then supplied to the demodulation unit 24. The demodulation unit 24 demodulates data from the supplied received signal and supplies the data to a subsequent circuit (not shown). The demodulation unit 24 further outputs a reception level signal indicating the level of the reception signal, and outputs a synchronization detection signal indicating when the built-in synchronization circuit is synchronized with the frequency, phase, and the like of the reception signal.

The parabolic antenna 16 is provided by an Az-XY mount having an Az axis 10, an X axis 12, and a Y axis 14,
It is supported on a moving body 26. In the figure, reference numerals 28 and 30
And 32 represent an Az-axis structure, an X-axis structure, and a Y-axis structure, respectively. These structures 28, 30
And 32 may include various members, such as a frame (or gimbal) of each axis, a motor, etc., which rotate when the corresponding axis is rotated. Also, the Az axis structure 28 is
It is also called a shaft turntable. The Az axis 10, the X axis 12, and the Y axis 14 are rotated by an Az axis motor 34, an X axis motor 36, and a Y axis motor 38, respectively. The three-axis arithmetic control circuit 40 receives signals from the potentiometers 48, 50, and 52 provided on the Az axis 10, the X axis 12, and the Y axis 14, or the Az axis structure 28, the X axis structure 30, and the Y axis structure 32.
_xbddet , x _det and y _det are input, and Δφ _xtd , Δθ _x and Δθ _y calculated using these are output to the Az axis motor drive circuit 42, the X axis motor drive circuit 44 and the Y axis motor drive circuit 46. . The Az-axis motor drive circuit 42, the X-axis motor drive circuit 44, and the Y-axis motor drive circuit 46 correspond to the motors 34, 36, and 38, respectively, based on the corresponding one of Δφ _xtd , Δθ _x and Δθ _y. Drive things.

The moving body 26 to be mounted has r _ddet or r
_Shaking detector 54 for detecting _xdet and p _ddet or p
A fluctuation detector 56 for detecting _ydet is mounted, and the three-axis arithmetic control circuit 40 outputs r _ddet and p _ddet (FIG. 4) or r _xdet and p from these fluctuation detectors 54 and 56.
_{Enter ydet} (Fig. 5). The moving body 26 further includes a device that provides φ _g to the three-axis arithmetic control circuit 40, for example, various navigation devices, compasses, for example, a gyrocompass 27. FIG. 6 shows a configuration of the gyrocompass 27 as a preferable example. The gyro compass 27 in this figure has an Az axis 58, an X axis 62 and a Y axis 64, and can rotate the follower ring 60 with the Az axis 58 on the same mounting surface as the Az axis 10 of the antenna mount. , The outer gimbal 64 is rotatably supported by the X-axis 62 on the follower ring 60, the inner gimbal 68 is rotatably supported by the Y-axis 66 on the outer gimbal 64, and the inner side of the inner gimbal 68. And a rotor 70 that rotates. In such a gyrocompass, the rotor 70 is directed almost to the north. 4 provided from the moving body 26 in FIG. 4 or the gyro compass 27 in FIG.
_g corresponds to a difference _φxdd between the direction of the rotation axis of the rotor 70 and the traveling direction of the moving body 26. Here, it is assumed that φ _g matches true φ _xdd with an accuracy that does not cause any practical problem.

FIGS. 7 and 8 show the functional configuration of the three-axis arithmetic control circuit 40 in the first and second embodiments. In addition,
These drawings are created as block diagrams, but this is for convenience of functional description, and does not mean that the present invention cannot be implemented in software.

As shown in the figure, the three-axis arithmetic control circuit 40
A target position input unit 100 for inputting _th and ε _th is provided. The target position input unit 100 holds and stores φ _th and ε _th input from the outside by a circuit (not shown). The target position input unit 100 includes a target position search unit 102 and a step track unit 104. The target position search unit 102 uses the reception level signal and the synchronization detection signal from the demodulation unit 24 when the position of the target T is unknown, such as when φ _th and ε _th have not been given from the outside after power-on. Then, φ _th and ε _{th at} which the received signal quality from the target T exceeds a predetermined level are searched. That is, until a sufficient reception level is obtained or until the demodulation unit 24 synchronizes with the reception signal, φ _tvh and ε _tvh , which are virtual values of φ _th and ε _th , are _{gradually changed} to φ _th and ε _th. The target position is searched for by supplying it to the subsequent stage. φ _tvh and ε
To gradually _change tvh, for example, φ
A method of adding a small value to the value on the register storing each of _tvh and _εtvh may be used. When searching for the position of the target T, it is preferable to use a plurality of sets of the above data along the time axis for statistical processing. Φ _tvh and ε _tvh at the end of the search can be regarded as true φ _th and ε _th . Further, step tracking unit 104, after the input or search for phi _th and epsilon _th, phi by _TVH and epsilon _TVH a trial and error gradually changing, the phi _TVH and epsilon _TVH as signal reception quality improves The change direction is detected, and φ _tvh and ε _tvh are gradually changed in that direction. Note that the same or similar method as that used in the search can be used for the method of detecting and evaluating the signal reception quality and the method of _{gradually changing} φ _tvh and ε _tvh .

The three-axis arithmetic control circuit 40 further _receives a moving object direction input unit 10 for inputting φ _g and supplying it as φ _xdd to a _subsequent stage.
6, r _ddet and p _ddet (FIG. 7) or r _xdep and p
_Ydet (Figure 8) Enter the r _d and p _d (FIG. 7) or r _x and p _y mobile supplied to the subsequent stage to the title compound (8) tilt angle input unit _108, φ xbddet, x _det and y Enter _det and φ
_It has a mechanical axis angle position input unit 110 that supplies _xbd , x, and y to the _subsequent stage. The three-axis arithmetic control circuit 40 further includes an Az axis control unit 112 and an X axis Y axis control unit 114. The Az-axis control unit 112 controls φ _th , φ _xdd , r _d or r
_x, type the p _d or p _y and phi _{xb d,} based on these Δ
Generate φ _xtd and output. The X axis Y axis control unit 114
_d or r _x, p _d or _{r y, φ xbd, ε th} , based on x and y, and generates and outputs a [Delta] [theta] _x and [Delta] [theta] _y. See the Summary of the Invention section for the method of generation. With such a configuration, in particular, the generation procedure of the Az-axis control error signal executed by the Az-axis control unit 112, the various advantages described above can be realized.

[Brief description of the drawings]

FIG. 1 is a shaft configuration diagram showing an example configuration of an antenna mount to which the present invention can be applied.

FIG. 2 is a shaft configuration diagram showing another example configuration of an antenna mount to which the present invention can be applied.

FIG. 3 is a coordinate relation diagram for explaining the principle of the present invention.

FIG. 4 is a block diagram illustrating a configuration of an apparatus according to the first embodiment of the present invention.

FIG. 5 is a block diagram illustrating a configuration of an apparatus according to a second embodiment of the present invention.

FIG. 6 is a shaft configuration diagram showing an example configuration of a gyro compass that can be used in the first and second embodiments.

FIG. 7 is a block diagram illustrating a functional configuration of a three-axis operation control circuit according to the first embodiment.

FIG. 8 is a block diagram illustrating a functional configuration of a three-axis operation control circuit according to a second embodiment.

FIG. 9 is a diagram showing the results of a simulation performed by the inventor to clarify the problem of the conventional azimuth tracking error.

[Explanation of symbols]

A antenna beam, T target, X _td , azimuth line of X _th target T, X ₀ Y ₀ Z ₀ horizontal true north coordinate system, X _d Y _d Z _d
Mobile coordinate system, XYZ Az axis rotary table coordinate system, X _dh Y _dh Z
_dh mobile virtual horizontal coordinate system, X _h Y _h Z _h antenna horizontal coordinate _{system, r d, r ddet, r} x, r td rolls, p _d,
p ddet, p _y, p _{td pitch, φ xdd, φ g, φ} xdh
Moving body direction, φ _th , φ _tvh , φ _tbd , φ _tbh target direction, ε _th , ε _tvh target elevation angle, φ _xbd , φ _xbddet , φ
_xbh X axis bearing angle, Δφ _xtd , Δφ _xth azimuth tracking error, x, y, x _det , y _det X, Y axis angular position, Δφ _xtd , Δθ _x , Δθ _y Control error signal for each machine axis, 10 Az axis, 12 X axis, 14 Y axis, 16 parabolic antenna, 24 demodulation unit, 26 moving object, 28 Az
Shaft structure (turntable), 30 X-axis structure, 32 Y-axis structure, 34 Az-axis motor, 36 X-axis motor, 38 Y
Axis motor, 403 axis operation control circuit, 42 Az axis motor drive circuit, 44 X axis motor drive circuit, 46 Y axis motor drive circuit, 48, 50, 52 potentiometer, 5
4,56 Motion detector, 100 target position input unit, 102
Target position search unit, 104 step track unit, 10
6 Moving body direction input unit, 108 Moving body tilt angle input unit,
110 mechanical axis angle position input unit, 112 Az axis control unit,
114 X-axis Y-axis control unit.

Claims (3)

[Claims] 1. An Az axis disposed on a moving body so as to face a vertical direction when the moving body is not tilted, an X axis disposed on the Az axis so as to be horizontal when the moving body is not tilted, and orthogonal to the X axis. X to do
A control device used in an antenna mount having a Y-axis disposed on an axis and supporting a directional antenna, comprising target position input means for inputting a target azimuth φ _th and an elevation angle ε _th in a horizontal coordinate system. Moving body direction input means for inputting moving body direction data that can be regarded as the direction φ _{xdh of the} moving body in the horizontal coordinate system or can be converted to φ _xdh ,
Az axis, X-axis and Y-axis of each angular position phi _xbd, a mechanical shaft angle position detecting means for detecting the x and y, the mobile inclination angle detection that detects a roll angle r _d and the pitch angle p _d of the moving object in the control apparatus comprising: means, and obtains a relative azimuth phi _tbh of the target in the horizontal coordinate system based on phi _th and the mobile orientation data, phi _tbh, the target in the mobile coordinate system based on r _d and p _d error [Delta] [phi _xtd of the determined relative orientation phi _tbd, the phi _xbd for phi _tbd
By generating an Az axis control error signal indicating the above, by applying a rotation in the direction to compensate Δφ _xtd to the Az axis based on the generated Az axis control error signal, the target with the beam of the directional antenna and Az axis control means for tracking respect to its orientation, r _d, p _d, and φ determine the roll angle r _x and the pitch angle p _y of the moving object in the Az-axis rotary table coordinate system based on _xbd, of x for r _x generates an error signal Y axis control indicating an error [Delta] [theta] _y of y determined based on both the error signal and at least the X-axis control indicating an error [Delta] [theta] _x p _y, the X-axis based on the generated X-axis control error signal By providing rotation in a direction that compensates for Δθ _x , the directional antenna is stabilized against fluctuations of the moving body around the X axis, and Δθ _{y is applied} to the Y axis based on the generated Y axis control error signal. By imparting rotation in a direction that compensates for Control apparatus characterized by comprising: a X-axis Y-axis control means for stabilizing against the upset around the Y axis to bring up the tracking respect to its elevation to the target and the directional antenna the mobile at. 2. An Az axis arranged on the moving body so as to be directed vertically upward when the moving body is not inclined, an X axis arranged on the Az axis so as to be horizontal when the moving body is not inclined, and the X axis. A control device used in an antenna mount having a Y-axis disposed on the X-axis so as to be orthogonal to the axis and supporting a directional antenna, comprising a target azimuth φ _th and an elevation angle ε _th in a horizontal coordinate system. Target position input means for inputting moving object direction data which can be regarded as the direction φ _xdh of the moving object in the horizontal coordinate system or can be converted to φ _xdh , Az axis, X axis Mechanical axis angular position detecting means for detecting the angular position φ _xbd , x and y of each of the Y axis and the Y axis, and the roll angle which is the lateral inclination angle of the moving body from the level fixed on the Az axis or the Az axis structure and about the X axis vertical inclination serving pitch of the moving body from the levels of r _x and the X-axis line direction A control apparatus comprising: a movable body tilt angle detection means for detecting the angular p _y, and calculates the relative azimuth phi _tbh of the target with respect to the moving body in the horizontal coordinate system based on phi _th and the mobile orientation data, phi _xbd , Az in the horizontal coordinate system based on the r _x and p _y
Obtains a virtual angle signal phi _XBH axis, for phi _tbh phi
_Generates an Az axis control error signal indicating the error Δφ _xtd of _xbh , and generates Δφ on the Az axis based on the generated Az axis control error signal.
Az-axis control means for causing the beam of the directional antenna to track the target with respect to its azimuth by imparting a rotation in a direction that compensates for _xtd , and an X-axis control error indicating an error Δθ _x of _{x with} respect to r _x imparting rotational direction to compensate for signal and at least p generates a Y-axis control error signal indicating the error [Delta] [theta] _y of y determined based on _y, [Delta] [theta] _x in X-axis based on the generated X-axis control error signal By doing so, the directional antenna is stabilized against fluctuations of the moving body around the X axis, and rotation is applied to the Y axis in a direction to compensate for Δθ _y on the basis of the generated Y axis control error signal. With this, the target is tracked with respect to the elevation angle by the beam, and the directional antenna is moved to Y of the moving body.
X-axis and Y-axis control means for stabilizing against oscillation around the axis. 3. The target position input means, while gradually updating the reception state of a signal from the target by the directional antenna above a predetermined level, as a virtual value φ _tvh and / or ε _th as φ _th and / or ε _th Target position searching means for inputting ε _tvh and / or _{tv tvh} and / or ε _tvh when a reception state of a signal from the target by the directional antenna exceeds a predetermined level.
Step tracking means for inputting φ _tvh and / or ε _tvh as φ _th and / or ε _th while updating φ _tvh and / or ε _tvh by trial and error and in small increments _starting from The control device according to claim 1 or 2, wherein