JPH04204177A - Attitude controllor for antenna on moving body - Google Patents

Abstract

PURPOSE:To improve the tracking property for the quick attitude change of a moving body by providing a second control means which sets a wide area for a small-region loop when the received level of a receiver is low before conical scanning and sets the narrow loop when the received level is high. CONSTITUTION:A second control means 4 sequentially broadens a small-region loop with the decrease in received level. Therefore, the scanning loop of conical scanning becomes wide when attitude change becomes quick, and the probability of missing a radiowave source is decreased. When the attitude change of a moving body becomes slow, the change in received level becomes slow. The radiowave source is accurately captured by the conical scanning. The received level of a BS antenna becomes high. At this time, the second control means 4 sequentially narrows the small-region loop of the conical scanning with the increase in received level. Therefore, the antenna attitude is precisely corrected in the direction where the received level becomes high. The antenna attitude is accurate set at the attitude where the optimum receiving level is set.

Description

Detailed Description of the Invention (Objective of the Invention) (Industrial Field of Application) The present invention aims to reduce the reception level of an antenna in order to compensate for a decrease in the reception level due to a change in the attitude of a mobile body such as a military vehicle with respect to a radio wave source. The present invention relates to an attitude control device for an antenna on a mobile body, which monitors and adjusts the attitude of the antenna in a direction that increases the reception level.

(Prior art) In antenna attitude control (gyro tracking), a gyro detects a change in the attitude of a moving object, calculates the attitude deviation of the antenna (relative to the radio wave source) due to the attitude change, and corrects the antenna attitude accordingly. If the pointing direction of the antenna deviates from the radio wave source, the attitude deviation will not be corrected forever.

Tracking using a continuous roving method (reception tracking), such as conical scanning, in which the antenna repeatedly scans a small area and shifts the scanning center to the position where the reception level is highest, provides sufficient tracking performance for the rapid attitude adjustment of a moving object. If the signal cannot be received due to obstacles such as tunnels or buildings, tracking will not be possible. Therefore, both gyro tracking and reception tracking may be used in combination. According to this, when there are radio wave obstacles such as tunnels and buildings, the gyro tracking interpolates the tracking between them. Since gyro tracking is feedforward control, gyro tracking alone tends to result in poor reception, but reception tracking such as conical scan corrects gyro tracking errors through feedback control.

One of this type of attitude control device is Japanese Patent Application Laid-Open No. 64-13801.
It is presented in the publication No. In this gyro tracking, the attitude of the moving body is detected by a yaw angle detector and a pitch angle detector, and the attitude of the antenna (azimuth direction and elevation direction) is changed in response to a change in the attitude of the moving body.

(Problem to be Solved by the Invention) Considering that the antenna must be accurately maintained in the desired direction in all situations of the moving object, this type of attitude control device is large-scale and expensive, and relatively expensive. It is not suitable for use in low-cost moving objects whose posture changes quickly. By the way, if tracking is performed using a continuous roving method such as kneel scan, which repeatedly scans a small area of the antenna and shifts the scanning center to the position where the reception level is highest, it will be difficult to respond to rapid changes in the attitude of the moving object during extreme movements. Therefore, sufficient tracking performance cannot be obtained.

An object of the present invention is to improve the tracking performance for fast posture changes of a moving object in tracking using conical scanning.

[Structure of the invention]

(Means for Solving the Problems) The attitude control device of the present invention provides an antenna (Ant) on a moving object.
) support mechanism (110-155) that rotatably supports the antenna (
driving means (141, 151) for rotationally driving the antenna (Ant) in the elevation direction and the azimuth direction;
t); a receiver (BSR) connected to the drive means (14
1, 151), the first control means (4) conically scans the antenna in a set small area loop in the elevation direction and the azimuth direction, and sets the antenna attitude at a position where the reception level (BSs) is high during the conical scan. ); and, before the conical scan, the reception level of the receiver (
BSs) is low, the small area loop is set to be wide;
If the reception level is high, set it narrower. A second control means (0: is provided.

Note that symbols in parentheses indicate corresponding elements or corresponding matters in the embodiment shown in one drawing and described later.

(Function) When the small area loop drawn by the conical scan is narrow and the attitude change of the moving object is rapid, the direction of antenna orientation tends to deviate from the radio wave source, and the reception level of the antenna tends to decrease. Since the control means (4) sequentially expands the small area loop as the reception level decreases,
As the attitude changes faster, the scanning loop of the conical scan becomes wider, reducing the probability of losing sight of the radio wave source.

As the attitude change of the moving body slows down, the change in the reception level slows down, the radio wave source is accurately captured by the conical scan, and the reception level of the antenna becomes high. At this time, as the reception level increases, the second control means ( 4) sequentially narrows the small area loop of the conical scan, so the antenna attitude is finely corrected in the direction of further increasing the reception level, and the antenna attitude is accurately determined to the attitude that provides the optimum reception level.

In other words, in conjunction with the attitude change speed of the moving object, when the speed increases, the scanning loop of the conical scan is widened to avoid tracking loss, and when the attitude change speed becomes low, the scanning loop of the conical scan is narrowed. The antenna posture that provides the highest reception level is determined.

Other objects and features of the present invention will become apparent from the following description of embodiments with reference to the drawings.

(Example) FIG. 1 shows an example of the present invention.
This antenna is installed in the vehicle shown in the figure, and controls the attitude of the BS antenna Ant for receiving stationary broadcasts.

The automatic is equipped with a yaw angular velocity detector 30, which is a vibration type gyro, which detects the yaw angular velocity (rotational angular velocity in the direction of course change) of the vehicle and sends an analog signal (yaw angular velocity signal) representing this to the interface 3. give to

Interface 3 removes noise from the yaw angular velocity signal,
After performing electrical processing such as amplification, the microcomputer 4
give to The microcomputer 4 includes a CPU and a RAM.
This is a computer system that includes electronic circuit elements such as , ROM, and system controller, and reads the yaw angular velocity signal by digitally converting it.

Interfaces 3 and 5 are connected to the microcomputer 4, and these interfaces 3.
5, an operation board 22. A BS receiver BSR, an azimuth motor driver AZD, and an elevation motor driver ELD are connected.

The radio wave reception signal of the BS antenna Ant reaches the BS receiver, where it is demodulated into a satellite broadcast signal and given to the display BSD, which displays a geostationary satellite television broadcast image. The satellite broadcasting signal is also given to the interface 5, and the ink-face 5 converts the radio wave reception signal into an analog signal BSs representing the signal level and gives it to the microcomputer 4. The microcomputer 4 is
The analog signal BSs is digitally converted and read.

Both the azimuth motor driver AZD and the elevation motor driver ELD include an electric circuit (motor driver) for selectively passing forward rotation energizing current and reverse rotation energizing current to the motor, and a combinatorial circuit (mainly CPU-based). controller), each of which receives a step rotation instruction signal (rotation angle in direction) from the microcomputer 4.
In response to this, the motor of each mechanism is energized to rotate by the specified angle in the specified direction, or the microcomputer 4
The motors of each mechanism are energized to rotate at the designated speed in the designated direction in response to a continuous rotation instruction signal (direction and speed) from the rotary encoder 1 of the azimuth mechanism.
48 and elevation mechanism rotary encoder 1
Count the electric pulses generated by antenna A.
The azimuth attitude (rotational position) data and elevation attitude (rotational position) data of nt are updated by the attitude change due to antenna drive, and the data indicating the antenna attitude at that time is always stored in the azimuth position register AZPR and the elevation position register ELPH. Hold.

FIG. 2a shows a mechanism for supporting the BS antenna Ant and determining its attitude. This mechanism rotates the BS anti-Ant in the azimuth direction (centered on the first axis Y) and in the elevation direction (centered on the second axis X). It is a drive mechanism.

The antenna Ant is a flat circular beam antenna with a relatively wide reception range, and is attached to the antenna bracket 110.
is fixed to.

FIG. 3 shows the directivity characteristics of the BS antenna Ant. The vertical axis is the CN ratio, and the horizontal axis is the angle between a perpendicular line passing through the center of the light-receiving surface (circular) of the antenna and a straight line connecting the center and the radio wave source (geostationary satellite). When this angle is about 86 or less, the CN ratio is 50% or more of the maximum CN ratio (15 dB).

Referring again to FIG. 2a, the antenna bracket 110
A horizontal shaft 113b (the center of which is the second axis X) is fixed to the angle 113a. The horizontal shaft 113b extends in a direction perpendicular to the drawing, and one end thereof is rotatably supported by a support arm 121a via a bearing (not shown). The support arm 121a is fixed to the rotating table 120. The other end of the horizontal shaft 113b is rotatably supported by another not-illustrated support arm similar to the support arm 121a via a bearing. The other support arm (not shown) is also fixed to the rotary table 120 at a position symmetrical to the support arm 121a with respect to the cylindrical shaft 116, which will be described later.

The rotary table 120 is roughly a disk-shaped spur gear, and has a guide hole 120h in its center and a gear 120 on its side circumferential surface.
a, and to the fixed base 130 via the bearing 122,
The gear 120a- is rotatably mounted around the rotation center axis (first axis) Y of the gear 120a-.

A gear 144 is engaged with the gear 120a of the rotary table 120, and this gear 144 is connected to the gear shaft 145 and the reducer 14.
0 and is rotationally driven by an azimuth drive motor 141. The speed reducer 140 and the motor 141 are fixed to a support base 146 that is fixed to the fixed base 130. A rotary encoder 148 is coupled to the gear shaft 145 and generates one electric pulse for each rotation of the gear shaft 145 through a predetermined small angle. This electric pulse is applied to an azimuth motor driver AZD.

A switch 147 for detecting the azimuth home position is installed opposite to the bottom surface of the rotary table 120.
A tapered hole (-point) into which the operator of the switch 147 falls is cut on the lower surface of the switch 147 at a position facing the operator. The switch 147 is open (off) when the operator is pressed on the bottom surface of the rotary table 120, and when the tapered hole faces the operator, the operator enters the hole, and the switch 147 is closed (on). : home position detection). While the rotary table 120 rotates once, the operator of the switch 147 enters the tapered hole and turns on (home position detection). The open/close signal of the switch 147 is given to the azimuth motor driver AZD and also to the microcomputer 4 via the interface 5.

Referring to FIG. 2b, which is a cross-sectional enlarged line I [B-IIB line in FIG. 2a, inside the reducer 140, the gear shaft 14
A worm wheel 143 is fixed to the worm wheel 5, and a worm 142 meshing with the worm wheel 143 is connected to a rotating shaft of a motor 141 (FIG. 2a).

When the motor 141 rotates forward, the gear 144 rotates in one direction, and the rotary table 120 rotates in one direction about the first axis Y. That is, the antenna Ant rotates about the first axis Y in the positive direction. When the motor 141 rotates in the opposite direction, the antenna Ant rotates in the opposite direction.

The guide hole 120h of the rotary table 120 is connected to the cylindrical shaft 116.
passes through the rotary table 120, and is movable in the direction in which the first axis Y extends with respect to the rotary table 120. Although not shown, a groove parallel to the first axis Y is carved on the side peripheral surface of the cylindrical shaft 116, and a groove parallel to the first axis Y is formed in the guide hole 120h of the rotary table 120. There is a rail-shaped protrusion, and this protrusion allows the cylindrical shaft 116 to move in the direction in which the first axis Y extends with respect to the rotary table 120, but cannot rotate around the first axis Y. be. Therefore, the turntable 12
0 rotates around the first axis Y, the cylindrical shaft 1
16 also rotates around the first axis Y.

A bin 117 is fixed to the upper end of the cylindrical shaft 116, and the link arm 11 is rotatably attached to the bin 117.
The lower ends of 5 are joined. The upper end of the link arm 115 is rotatably connected to a pin 112 fixed to the angle 111 of the bracket 110.

The bracket 110 is attached to the horizontal axis 11 from the angle 113a.
3b in the horizontal direction perpendicular to the extending direction (perpendicular to the plane of the paper in FIG. 2a), 'When the cylindrical shaft 116 moves upward in FIG. 2a, the antenna An
t rotates counterclockwise (rotates upward) about the horizontal axis 113b, and when the cylindrical shaft 116 moves downward, the antenna Ant rotates clockwise (rotates downward).

The outer surface of the lower half of the cylindrical shaft 116 is carved with a gear 116a, which is ring-shaped rather than threaded. Each of the crests and troughs of the ring-shaped gear 116a is parallel to the direction perpendicular to the first axis Y. A gear 154 meshes with this ring-shaped gear 116a.

Referring also to the large cross section 2c on the ncinc line in FIG.
A worm wheel 153 is fixedly attached thereto. The worm wheel A 152 meshing with the worm wheel 153 is connected to the rotating shaft of the elevator drive motor 151 (FIG. 2a). The reducer 150 and the motor 151 are mounted on the fixed base 1
It is fixed to a support stand 146 fixed to 30.

When the elevator drive motor 1'5-1 rotates forward, the gear 154 rotates clockwise in FIG. 2a, the cylindrical shaft 116 moves downward, and the antenna Ant rotates clockwise (rotates upward). When the motor 151 rotates in the opposite direction, the antenna Ant rotates counterclockwise (rotates downward).

The link arm 11 is moved upward and downward by the cylindrical shaft 116.
5 is applied with a rotational force about the bin 117, and the link arm 115 rotates about the bin 117. During this rotation, so that the rotation of the link arm 115 is not hindered,
A groove 118 is cut into the upper end of the cylindrical shaft 116, as shown in FIG. 2d.

As described above, the gear 154 meshes with the gear 116a of the cylindrical shaft 116, and each of the peaks and valleys of the gear 116a forms a ring that goes around the side circumferential surface of the cylindrical shaft 116. Since it is parallel to the first axis Y, the cylindrical shaft 116 is not restricted in rotation by the gear 154 and rotates about the first axis Y both when the gear 154 is stationary and when it is rotating. It can rotate, and this rotation itself causes the cylindrical shaft 116 to turn into gear 15.
It does not go up or down with respect to 4.

Referring to FIG. 2c, a cam plate 156 is fixed to the gear shaft 155 of the gear 154. As shown in FIG. This cam plate has a step on its outer peripheral edge.

An upper limit switch 158 is provided on the outer peripheral surface of this cam plate 156.
and the lower limit switch 159 are facing each other, and when the elevation rotation angle of the antenna Ant is within a predetermined range, the operators of the switches 158 and 159 are opposite to the cam plate 1.
Since it faces the small radius outer peripheral surface of switch 15
8.159 both open off). When the antenna Ant rotates clockwise and reaches the clockwise rotation limit position (upward limit), the tapered surface of the cam plate 156 that switches from the small radius outer circumferential surface to the large radius outer circumferential surface presses the operator of the switch 158, and thereby Switch 158 is turned closed (on). When the antenna Ant rotates in the direction of the half-hour hand and reaches the limit position (downward limit) of rotation in the direction of the half-hour hand, the tapered surface of the cam plate 156 that switches from the small radius outer circumferential surface to the large radius outer circumferential surface presses the operator of the switch 159. This turns switch 159 closed (on). switch 15
The opening/closing signals of 8 and 159 are from the elevation driver E.
The signal is applied to the LD and also to the microcomputer 4 via the interface 5.

A rotary encoder 157 is connected to the worm 152, and the rotary encoder 157 is connected to a rotary encoder 157.
Generates pulsed electrical pulses.

This electric pulse is generated by the elevation motor driver ELD.
given to.

As described above, the reducer 140 and the motor 141 are used to rotate the antenna Ant around the first axis Y, and the horizontal axis 113b (second axis X) is perpendicular to the first axis Y. Since the speed reducer 150 and the motor 151 for rotationally driving the motor 150 are both fixed to the fixed base 130, no sliding connection means is required to supply power to the motors 141 and 151.

Referring to FIG. 2a, the converter (onv) is attached to the antenna bracket 110 and converts the 12 GHz band satellite broadcast radio waves received by the antenna Ant to the 1 GHz band BS.
-Convert to IF. The converted signal is transferred to the cable 161
to the rotary joint 160 via B
S receiver BSR (FIG. 1).

However, the converter Co fixed to the bracket 110
Since nv rotates around the first axis Y and the horizontal axis 113b together with the antenna Ant, the signal line and power receiving line of the converter Conv and the BS receiver BSR in the fixed part
It is necessary to connect the signal line and the power supply line through a sliding connection means.

In this embodiment, since the elevation rotation range of the antenna Ant about the horizontal axis 113b only needs to be 360 degrees or less, the electric cable 161 consisting of the signal line and the power receiving line of the converter Conv is relatively flexible. In addition to having a high degree of flexibility, the shaft is provided with a length that allows for rotation of 360 degrees or more, and the wire is passed through the cylindrical shaft 116 and connected to the rotary joint 160. For rotary joint 160.

An electrical cable 162 from the BS receiver BSR is connected, and this rotary joint 160 connects the leads of cables 161 and 162 to be electrically connected to each other.
Despite relative rotation about the first axis Y, they are electrically connected to each other.

With respect to the rotation of the antenna Ant about the horizontal axis 113b, the cable 161 swings roughly about the pin 117.

Thus, in this embodiment, only one set of sliding connection means (rotary joint 160) is used.

The elevation drive motor 151 of the elevation mechanism (150, 151) rotationally drives the drive gear 154, but since the cylindrical shaft 116 reciprocally driven by the drive gear 154 slides with respect to the rotary table 120, the rotary table 1
20 and an azimuth mechanism (144,
140°141) is the elevation mechanism (150°1
51) and is not driven by the elevation mechanism (1
50,151>. The objects supported by the elevation mechanism (150, 151) are substantially the BS antenna Ant, the BS controller Conv, the link arm 115, and the cylindrical shaft 116, and since the load is small, the inertial force is small, and the second axis Azimuth drive and elevation drive of the BS antenna Ant centered at (X) can be performed at relatively high speed, and positioning can be performed with relatively high precision.

Referring to FIG. 4, the operation board 22 has an antenna A.
nt azimuth data (hereinafter referred to as azimuth data), elevation (downward)
Corner data (hereinafter referred to as elevation data).

LC for displaying reception level and various messages
D (Two-dimensional liquid crystal display board)23. A START key 24 for instructing automatic attitude control of the antenna 30.
Stop (STOP) key 25 for instructing to stop automatic attitude control of antenna Ant. Up key (U key) for manual attitude control 26. Down key (D key) 27
．． A right key (R key) 28 and a left key (L key) 29 are provided.

FIG. 5 shows an outline of the control operation of the microcomputer 4. A power supply circuit (not shown) is connected to the vehicle battery when the vehicle ignition key is in the engine operating position (ignition key switch on).
A predetermined voltage is applied to each part of the electric circuit shown in FIG.

Note that a battery voltage is also applied to the motor drivers AZD and ELD for energizing the motor.

When a predetermined voltage is applied to itself, the microcomputer 4 executes "system initialization" (subroutine 1: hereinafter, the words "step" and "subroutine" are omitted in parentheses, and only the numbers assigned to them are written). , internal register.

The timer, counter, etc. are set to the contents specified for the standby state, and a signal specifying non-operation (de-energization) is set to the output boat. Then click [System Initialize] (
In step 1), "initialization of antenna posture" is executed. In this case, the antenna Ant is set at the home position (switch 147 on) in the azimuth direction, and at the limit position for half-hour hand direction rotation (downward rotation) in the elevation direction (switch 159 on), that is, the antenna Set the posture as the origin and clear the posture registers (azimuth position: register AZPR/elevation position: register ELPR).

When the microcomputer 4 receives the Read7 signal from both motor drivers AZD and ELD, it reads 5T.
A loop is formed to execute the manual operation process of step 4 (hereinafter referred to as S) until the ART key 24 is turned on.

The manual operation process will be explained with reference to the flowchart shown in FIG. When the U key 26 is operated, the microcomputer 4 proceeds from 330 to S31, where the upper elevation limit switch 158 is turned on (closed).
Check for off (open).

If switch 158 is on (closed), antenna A
The attitude of ol in the elevation direction is at the upper limit of the elevation angle, and further upward driving is impossible, but if not, at 332 the elevation motor driver ELD
Instructs to execute 1-slep up shift processing. Further, when the D key 27 is operated, the process advances from 333 to 534, where it is checked whether the lower elevation limit switch 159 is on (closed) or off (open). Switch 159 is on (closed)
If it is, the attitude of the antenna Ant in the elevation direction is at the lower limit of the depression angle, and further downward driving is impossible, but if not, the elevation motor driver ELD is shifted down by 15 steps at 335. Instruct execution of processing.

If the R key 28 is operated, the microcomputer 4 proceeds from 336 to 337, where it instructs the azimuth motor driver AZD to shift to the right by 5 steps (clockwise rotation: forward rotation), and then presses the L key 29. If there is an operation, the process proceeds from S38 to 339, where the azimuth motor driver AZD is instructed to shift 1s+ep to the left (half-hour hand direction rotation degree reverse rotation).

Referring again to FIG. 6, the microcomputer 4
At 340, motor driver AZD.

1 5 step right shift, 15 step left shift by ELD.

Wait for l Nep up shift or l 5 rep down shift to be executed, and in S41 motor driver AZ
D. Read Az data and EL data transferred from ELD. Additionally, at 342, the receiving 1z Bell BSs
is read and stored in register Ll, and in S43,
Az data, EL data, and reception level BSs of register L1 are displayed on LCD 23.

The microcomputer 4 includes S4 and S5 (Figure 5).
, when the 5TART key 24 is turned on, S
In step 5, "initial search JS5" shown in FIGS. 7a, 7b, and 7c is executed.

The contents of the initial search JS5 will be explained with reference to FIGS. 7a, 7b, and 7c.First, the concept of the initial search JS5 will be explained with reference to 10wJ. antenna while monitoring Ant
From the position indicated by the data in the register ELS, the attitude in the elevation direction of the Register E
From the position +11° indicated by the LS data to the upper limit position, and finally at the position -216 indicated by the register ELS data.
to the lower limit position. 1 in 1 step 16
It changes step by step, and scans one rotation in the azimuth direction for each step change.

One rotation scan in the azimuth direction is also changed by one step 16. For each step drive in the azimuth direction,
Also, for each step drive in the elevation direction, the received signal level BSs of the receiver BSR is read and checked to see if it is a threshold value T) (2 or more for determining whether reception is possible), and if it is 782 or more, , then "End initial search JS5.

To explain more specifically with reference to FIG. 7a, first, it is checked whether the data in the register ELS indicates the origin (0) of the nilevage carbon (S5-Oa). In this embodiment, the register ELS is the microcomputer 4.
Since the register ELS is allocated to an area of the memory in the computer 4, when the power of the computer 4 is turned off, the contents of the register ELS will be data indicating zero the next time the power is turned on.

In this case, the attitude of the antenna Ant is the origin (azimuth position 0, elevation position 0) in [System Initialization JSI]. So in this case,
Computer 4 connects the elevation driver ELD to
Instructs elevation drive to the elevation midpoint (midpoint between the upper and lower limits). In response to this instruction, the driver ELD drives the antenna Ant to the midpoint of the elevation, and transfers the position data (EL data) of the midpoint of the elevation to the computer 4. Computer 4 writes this position data (midpoint) to register ELS (S
50b).

"Register E when proceeding to initial search J (35)"
When LS has data other than the origin, this means that the antenna drive after the "initial search" (S5) has already been executed once since the power was turned on to the system shown in Figure 1, and S'' , the elevation position when the reception level is suitable is written in 313a, which will be described later.In this case, the data in register ELS is not updated.

Next, in 350, the Az data at that time is stored in registers A1 and A2, and the EL data is stored in register E2.
Then, ELS+10 is stored in register E1.

After this, the reception level is read at 352. When the value is equal to or higher than the predetermined level THI, the microcomputer 4 immediately returns to the main routine from S53 (ends the initial search), but the microcomputer 4 returns to the predetermined level 781.
If it is less than 354, the process proceeds to step 354 and the attitude of the antenna Ant is changed. In this attitude change, first, if the elevation upper limit switch 158 is not on and the elevation position E2 has not reached the upper limit E1 of the first search area, the process proceeds from S54 to 555a-4S56, where the elevation motor driver ELD Instructs to shift upward by 15 steps, and increments the value of register E2 by 1 at 357. Upon receiving the shift end signal from the motor driver ELD, the microcomputer 4 executes "azimuth scanning" AZS.

"In azimuth scanning JAZS, first read the received signal level BSs (358), check whether it is 782 or higher (S59), and if it is 782 or higher, r
Finish "Initial Search".

If it is less than 782, check whether the azimuth home position switch 147 is on (home position), and if it is not on, the azimuth position A2 is set to 1@left of the initial position (Az data when entering "initial search JS5"). Check whether it is in the position (one rotation) (362), and if not, instruct the driver AZD to shift 15 steps to the right, and increment the current azimuth position data A2 by 1 (364).Return to 358 and receive The above is repeated while monitoring the level. When the home position switch 147 is turned on, the antenna is rotated one azimuth leftward (361). This is to avoid two or more consecutive rightward rotations.

Azimuth scan (AZS) rotates once in the right direction (from A1 to A
l-1: To be exact, when the clockwise rotation from A1 to A1 becomes one rotation, it returns to S52 and turns 15te in the elevation direction.
Perform a p-up shift.

Reference is now made to Figure 7b. In this way, register E
From the LS elevation position to the position 10" above (if the upper limit is reached by then, the upper limit will be reached), even if the azimuth direction is searched in the first area around the entire circumference, the reception level is B.
If Ss does not become 782 or more, then register ELS
In order to search from the elevation position to a position 20" below, first instruct the register ELS to shift down to the elevation position (565), then in 5sob, the Az data at that time is stored in registers A1 and A2.
and store the EL data in register E2, ELS-20
is stored in register E1. Then, every time the motor is driven down one step in the elevation direction, a search (AZS) in the azimuth direction is performed. In this case, the reception level BSs is read each time it is shifted to the right in the azimuth direction by 15 steps, and each time it is shifted down by 1 step in the elevation direction, and if it is 782 or higher, the initial search ends there, but the register ELS is Even when searching the second small area at 120° from the elevation position, the reception level BSs
is not 782 or more, the right half of Fig. 7c (S66
~AZS), the third small area from the elevation position +11° of the register ELS to the upper limit is searched. If the number is still not 782 or more, the fourth small area from the elevation position -21'' of the register ELS to the lower limit is searched in the process shown in the left half of FIG. 7c (S67 to AZS).

If the reception level BSs does not reach 782 or higher even after completing the search for this fourth small area, it means that an appropriate reception level has not been obtained even though the entire range of antenna postures has been searched.

Therefore, in this case, proceed from 554d to 555d and L
``Unreceivable'' is displayed on the CD 23 and the process returns to 53 of the main routine (FIG. 5).

"In the initial search JS5, the reception level BSs or the predetermined value 78
When searching for the attitude of antenna Ant that is 2 or more, the fifth
At 36a in the figure, the yaw angular velocity Yas detected by the yaw angular velocity detector 30 is read. Then, the data YAR of the speed register YAR (the sign specifies the direction of rotation, and the absolute value of the numerical value specifies the speed) is transferred to the azimuth motor driver A.
Transfer to ZD (6c).

The azimuth motor driver AZD rotationally biases the azimuth motor 141 so that when the sign of the data YAR is negative (the automatic base rotates counterclockwise), the antenna Ant is rotated to the right, and when it is positive, the antenna Ant is rotated to the left. , the antenna Ant monitors the pulses generated by the rotary encoder 148.
The rotation speed of the azimuth motor 141 is controlled so that the rotation speed matches the speed specified by YAR.

S6c data YAR to azimuth motor driver AZD
, the microcomputer 4 starts a T1 timer (internal timer), although it is not shown in the drawing. Then, in order to repeatedly execute S6a, S6c, 314, 517, etc. with a period T1, 313,516
Alternatively, when returning from 317 to S6a, wait for the T1 timer to time out, and when the time has elapsed, proceed to S6a.

Microcomputer 4 receives the reception level BS at the next 510.
Read s and write to register LL, antenna Ant
After reading Az data and EL data indicating the attitude of the motor driver AZD and ELD, these data are displayed on the LCD 23.

(1) In 313, the reception level BSs at this time, that is, the value of the register L1, is compared with the predetermined level THI, and as long as the value of the register L1 is equal to or higher than the predetermined level TH1, 36 a-+S 6 c-'S 8-'S 10→5
By repeating the loop 13→513a→S6a→..., the yaw angular velocity Ya detected by the yaw angular velocity detector 30
Attitude control processing (I) of the antenna Ant based on s is executed.

That is, while the reception level BSs is equal to or higher than the first set value THI, if there is a change in the yaw angular velocity Yas, the attitude of the antenna Ant is corrected by 1 corresponding to the change. While this is continuing, if the 5TOP key 25 is turned on, this is read in S8 and 53 of the flow shown in FIG.
(Return to standby state).

At step 313a, the elevation position data when proceeding there is updated and stored in the register ELS. Therefore, when tracking is stopped in response to turning on the stop instruction key 25, and then executing "initial search J (S5)" in response to turning on the start key 24 again, the reception level BSs is determined by the previously executed tracking. Since the last elevation position data where the voltage was 781 or more has been written, starting from the last elevation position where the voltage was 781 or more, the first small area, the second small area, and the second small area are written in the upward direction. 3
Area searches are performed in this order until a reception level of TH2 or higher is obtained in the small area and the fourth small area.

The above-mentioned loop (56a-4-56c-
438-=S 10→S 13-=S 13a-4s6
a→...), the reception level BSS, that is,
When the value of the register L1 becomes less than the predetermined level TH1, the microcomputer 4 detects this in S13 and
3, the process advances to S14, and "reception tracking" S14 is executed.

(II) The contents of "reception tracking" S14 will be explained with reference to FIGS. 8a, 8b, and 8c.

First, the concept will be explained with reference to FIG.

FIG. 10 is a conceptual diagram showing the scanning position when the antenna is conically scanned over a minute range.

In this conical scanning of a minute range, when the orientation direction of the antenna before entering this conical scanning is the origin 0, the antenna moves from the origin O to point 1, from point 1 to point 2, and finally to point 8. "Tracking 1" shifts the pointing center point and reads the reception level at each point, from origin 0 to point 9, from point 9 to point 10,
...Finally, "tracking 2" shifts the directional center point of the antenna to point 20 and reads the reception level at each point, from origin 0 to point 21.
, from point 21 to A22, and finally to point 28 and "tracking 3" to read the reception level at each point, and from origin 0 to point 29 and from point 29 to point 3.
0,... Finally, there are four types of "tracking 4" in which the center point of antenna direction is shifted to point 36 and the reception level is read at each point, and "tracking 1" to "tracking 4" gradually change to conical scanning. has a wide scanning loop.

Although the r-tracking IJ can precisely detect points where the reception level is high, there is a high probability of losing sight of the radio wave source when the vehicle's attitude changes rapidly. With "Tracking 4", it is possible to track the radio wave source even when the vehicle's attitude changes quickly, but it is difficult to accurately point to a point where the reception level is high.

See Figure 8a. When proceeding to "Reception tracking" 14, first check whether the reception level BSs is TH2 or higher,
If TH2 or more, the conical scan has succeeded in tracking the radio wave source, so the l-step scanning loop becomes narrower for tracking No., j. Update to 1 smaller number (
131-133). In other words, when tracking 4 (j = 4), tracking 3 (j mi 3) is set, and tracking 3 (j
= 3), set tracking 2 (j = 2), and when tracking 2 (j = 2), set tracking 1 (j = 2).
1) Set. When tracking 1 (j=1), such a change is not made because tracking 1 is the smallest loop scan.

If the reception level BSs is less than TH2, tracking of the radio wave source by conical scanning is not in time for changes in the attitude of the car, and this is considered to have caused the antenna's pointing direction to deviate from the power source, so tracking No.

J, the one-step scanning loop becomes wider. Update the value to one larger (131, 134.135).

In other words, when tracking 1 (j=1), tracking 2
(Set j=2>, and if tracking 2 (j=2), set tracking 3 (j-3). Tracking 4 (j
= 4), tracking 4 is the largest loop of scanning, so j is set to O and (145) r tracking search 17 is executed. The contents of the "tracking search" will be described later.

When the tracking No. is determined in this way, the tracking No.

(141-144). The contents of tracking 1 to tracking 4 are the same. Therefore, only the contents of tracking 3 will be explained here. In tracking 3, loop scanning as shown in FIG. 11 is performed, as also shown in the 10th meter. Rotate the main beam of antenna Ant (21 → 22 → 23 → 24 → 25 → 26 → 27 → 2
8 → 21 → ...), and when the target radio wave source is at the center of rotation of the antenna beam, the reception level will be this rotation (scanning)
This method takes advantage of the phenomenon that, although it remains substantially constant during scanning, if the target radio wave source deviates from the center of rotation of the beam, the reception level fluctuates during scanning and a maximum value appears.

In Figure 11, the squares are in the elevator direction (U/D
) and 1 step (1@) in the azimuth direction (R/L)
and each point 21, 22, 23° 24.25.26.2
7 and 28 are projection points 9 of the main beam (center) of the antenna Ant. Point O is the rotation center of the antenna beam (direction center point in the attitude immediately before starting scanning), and the arrow indicates the shift direction of the attitude of the antenna Ant. It is also assumed that there is an isotropic antenna (isotropic point radio wave source) at point a. Hereinafter, "reception tracking" S14 from the state where the antenna Ant is directed to point 0 will be explained with reference to FIGS. 8b, 8c, and 11.

l), drive the antenna Ant from the starting point 0 to the point 1 S7
0 to 573), the reception level was memorized at point 1 (S
84) After that, shift 2 steps to the right in the azimuth direction and shift 1 step downward in the elevation direction to direct it to point 2. 574) Store the reception level BSs at point 2 (S84)
.

2) 8th, shift one step to the right in the azimuth direction.

Shift 2 steps downward in the elevation direction and direct to point 3 375) Store the reception level at point 3 (384)
.

3) Next, shift one step to the left in the azimuth direction.

Shift 2 steps downward in the elevation direction and direct to point 4 576) Store the reception level at point 4 (3g4)
.

4) First, shift 2 steps to the left in the azimuth direction.

Shift one step downward in the elevation direction and point towards point 5, S7? ) Store the reception level at point 5 (S84)
.

5) First, shift 2 steps to the left in the azimuth direction.

Shift one step in the elevation direction to point 6 (37g) Store the reception level at point 6 (S84)
.

6) Next, shift one step to the left in the azimuth direction.

Shift 2 steps upward in the elevation direction and direct to point 7. 579) Store the reception level at point 7 (S80°?) First, shift 1 step to the right in the azimuth direction.

Shift 2 steps in the elevation direction and direct to point 8 (380) Store the reception level at point 8 (384)
.

As described above, one conical scan is completed, and the reception levels BSs of all the points (8 points) are written in the registers FOR1 to FOR8.

8) Next, the reception levels from point 1 to point 8 are compared to find the point with the highest reception level (387-91).

9), and the attitude of the antenna Ant is determined so that the center of rotation of the antenna beam is aligned with the obtained maximum point (S9).
2).

When point a shown in Fig. 11 is the position of the radio wave source, the magnitude of the reception level is as follows: point 1> point 2> point 8> point 3> point 7> point 4> point 6> point 5 Therefore, the point with the highest reception level is point l. Therefore, the attitude of the antenna Ant is set so that the directional center of the antenna beam is aligned with point 1.

As mentioned above, in "Tracking 313143 (same for tracking 1, 2 and 3) 1, one loop of conical scanning of a minute range is performed around the central axis (point 0) of the original antenna beam, The highest point of the reception level is detected, and the attitude of the antenna Ant is set so that the center axis of the antenna beam is placed there. Therefore, when the radio wave source moves relative to the antenna Ant, the antenna beam Attitude control is performed in such a manner that the locus of the central axis (point O) moves together with the radio wave source, and the antenna Ant tracks the radio wave source.

In addition, since 36a and S6c are executed immediately before the above-mentioned one-time conical scanning and attitude setting (see Fig. 5), (n
) is being repeatedly performed, the attitude control (1) above is also being executed.

(m) "Tracking search" 317 in Figures 9a and 9b
FIG. 12 is a schematic diagram for explaining the processing concept of "tracking search" 317.

Referring to these drawings, 3100 is the initial setting, and the state in which the antenna Ant is directed to the dot shown in FIG. 12 is when TSC=0.

1) Check whether the TSC value is 4 or less at 3101.

As long as the TSC value is 4 or less, proceed to 3102 5102
Check the status of switch 158 and if it is not on, 31
At G3, the motor driver ELD is instructed to shift up by one step. This is the scanning from five points θ to 5 in FIG. When the TSC value is 5 or more in 3101, 3104
Proceed to.

2) Check whether the TSC value is 54 or less at 51θ4. As long as the value of TSC is 54 or less, the process advances to 5105 and instructs the motor driver AZD to shift right by 1 step.

This is the scan from points 5 to 55 in FIG. 310
If the TSC value is 55 or more in step 4, the process advances to step 5106.

3) Check at 3106 whether the TSC value is 64 or less. As long as the value of TSC is smaller than 65, the process advances to step 5107, where the state of the switch 159 is checked, and if it is not on, the motor driver ELD is instructed to shift down by one step at step 3108. This is the scan from points 55 to 65 in FIG. When the TSC value is 65 or more in 3106, the process advances to 31G9.

4) Check whether the TSC value is 164 or less at 5109. As long as the value of TSC is 164 or less, the process advances to 5ilo and instructs the motor driver AZD to shift left by 1 step. This is the scan from points 65 to 165 in FIG. 5109 and the TSC value is 165 or more, 31
Proceed to step 11.

5) Check whether the TSC value is 174 or less using 5ill. As long as the TSCv value is 174 or less, proceed to 3112, check the state of the switch 158 in 3112, and if it is not on, take one step to the motor driver ELD in 3113.
Instructs to shift up. This is points 165-17 in Figure 12.
This is a scan up to 5. If the TSC value is 175 or more in 5111, the process advances to 5114.

[i) At step 5114, it is checked whether the TSC value is 224 or less. 3115 as long as the TSC value is 224 or less
, and instructs the motor driver AZD to shift one step to the right. This is the scanning of points 175 to 225 (previous point 5) of the 121 il. When the TSC value is 225 or more in 3114, the process advances to 511G.

? ), as long as the value of 311G-C'TSC is 229 or less, proceed to 5117, check the state of switch 159 in 5117, and if it is not on, turn off the motor driver EL in 511g.
Instruct D to shift down by 11imp. This is the scan from point 225 (previous point 5) to point 230 (previous point O) in FIG.

8) When the TSC value is 230 or more in 511G, and when the shift is completed by instructing the shift as described above, execute 512Q and read the reception level, and if it is 782 or more in 5121. If it is 782 or more, the process returns to the main routine (FIG. 5).

If it is less than 782, the reception level BSs is read again in 5123, and in 5124 it is checked whether it is higher than the second set value TH2.
The value of C is updated to a value larger by 1, and the process proceeds to 5101.

By the above processing of 3101 to 5125, reception level B
Until Ss becomes equal to or higher than the second set value TH2, as shown in Fig.
,3. ...230 (0) in this order, and it is checked whether the reception level is 782 or higher at each point. 2 points if less than 782
When reaching 30 (b=o), that is, returning to the original starting point, the TSC is set to 0 at 3119 and turned on again, so that the same search scan is performed.

During such a search scan, each time a point is reached,
5122 is the motor energizing parameter set (S6a, S6
b, the same as the contents of S6c) is executed, and the yaw angular velocity Y
Since the attitude change corresponding to as is executed, the position of the base point (b-0) does not change while there is no change in the attitude of the vehicle.
When there is a change in the attitude of the vehicle, the base point automatically shifts accordingly, but the search scanning range (FIG. 12) with respect to the base point does not change.

While the radio waves are blocked by an obstacle, the above-described "search scan" S17 is repeated, and if the attitude of the vehicle changes during this time, the base point of the search scan is shifted in conjunction with the change in attitude of the vehicle. Therefore, when the radio wave is interrupted, the search scan of the locus shown in Fig. 12 is repeated with the position of the beam center axis of the antenna just before that as the base point (b-0: Fig. 12) until the radio wave is received. If there is a change in the vehicle's attitude during that time, the reference point will shift in conjunction with the change in attitude of the vehicle.

To summarize here, (1) When the reception level BSs is higher than or equal to the 1st rubel THI, the antenna An
The attitude of t is changed.

(II) When the reception level BSi is less than 781 or more than 782, a conical scan and an antenna attitude change to the optimum pointing direction obtained thereby are performed in addition to (1) above.

(m) Reception level BS even with tracking 4 conical scan
When s is less than the second level TH2, in addition to the above (summer), a tracking search (FIG. 12) is performed over a wider range than the conical scan.

From the description of the above embodiments, one aspect of the present invention is a moving object other than a road vehicle such as an automobile9 train, that is, a ship.

It is easy to understand that it can also be applied to aircraft etc.

In the embodiment described above, the data ('') specifying one of tracking 1 to 4 and the elevation position when the reception level is suitable are stored in one area (register j, register register) of the internal memory of the computer 4. ELS), so when computer 4's power is turned off,
The tracking number, designated data, and position information are then lost. Therefore, the computer 4 may be provided with a non-volatile memory and the data of register j and register ELS may be written therein, and some Cζs back up the computer 4 with the on-vehicle battery power even when the engine key switch is off. It may also include a power supply circuit.

〔Effect of the invention〕

According to the invention of the present application, when the small area loop drawn by the conical scan is narrow and the attitude change of the moving object is rapid, the antenna's directional direction tends to deviate from the radio wave source and the reception level of the antenna tends to decrease. At this time, the second control means (4) sequentially widens the small area loop as the reception level decreases, so as the attitude change becomes faster, the scanning loop of the conical scan becomes wider and the radio wave source is lost. The probability of this happening is reduced.

As the attitude change of the moving body slows down, the change in reception level slows down, the radio wave source is accurately captured by conical scanning, and the reception level of the antenna increases. At this time, the second control means (4) sequentially narrows the small area loop of the conical scan based on the rise in the reception level, so that the antenna attitude is finely corrected in the direction of further increasing the reception level, making it optimal. The antenna attitude is determined accurately to the attitude that provides the reception level.

In other words, in conjunction with the attitude change speed of the moving object, when the speed increases, the scanning loop of the conical scan is widened to avoid tracking loss, and when the attitude change speed becomes low, the scanning loop of the conical scan is narrowed. The antenna posture that provides the highest reception level is determined.

[Brief explanation of the drawing]

FIG. 1 is a block diagram mainly showing the configuration of an electric circuit section according to an embodiment of the present invention. FIG. 2a is a longitudinal sectional view of the antenna support mechanism of this embodiment. FIG. 2b is an enlarged sectional view taken along line I[B-IIB in FIG. 2a. FIG. 2c is an enlarged sectional view taken along the line mc-mc of FIG. 2a. FIG. 2d is an enlarged perspective view showing the top surface of the turntable 120 shown in FIG. 2a. FIG. 2e is a perspective view showing the antenna Ant shown in FIG. 2a mounted on an automobile. FIG. 3 is a graph showing the radio wave reception characteristics of the antenna Ant shown in FIG. 2a. FIG. 4 is an enlarged plan view of the operation board 22 shown in FIG. 1. FIG. 5 is a flowchart showing an overview (main routine) of the control operation of the microcomputer 4 shown in FIG. FIG. 6 is a flowchart showing the contents of "manual operation" 4 shown in FIG. Figures 7a, 7b and 7c are similar to those shown in Figure 5.
5 is a flowchart showing the contents of "Initial Search" 5. FIGS. 8a, 8b and 8C are shown in FIG.
14 is a flowchart showing the contents of "Reception Tracking" 14. FIGS. 9a and 9b are flowcharts showing the contents of "tracking search" 17 shown in FIG. FIG. 10 is a graph showing a conical scan loop of the antenna Ant by the "reception tracking" 14 shown in FIG. 8a, where the horizontal axis shows the azimuth direction and the vertical axis shows the elevation direction. FIG. 11 shows the [tracking 3J] shown in FIGS. 8b and 8C.
143 is a graph showing the amount of change in the attitude of the antenna Ant according to No. 143, in which the horizontal axis shows the azimuth direction and the vertical axis shows the elevation direction. FIG. 12 is a graph showing the amount of attitude change of the antenna Ant due to the "tracking search" 17 shown in FIGS. 9a and 9b, and the horizontal axis is the azimuth direction. The vertical axis indicates the elevation direction. 3: Interface 4: Microcomputer (first control means, second control means) 5: Interface Ant: Antenna (antenna) Conv: BS=l Parter BSR: BS receiver (receiver) BSD: CRT AZD: Azimuth motor driver Remi ELD: Elevation motor driver 10: Azimuth rotation drive mechanism 20: Elevation rotation drive mechanism 22: Operation board 30: Yaw angular velocity detector 110: Antenna bracket 111.113a, 114a: Angle 112: Pin
113b: Second axis (X) Y: First axis 11
5: Link arm 116: Cylindrical shaft 116a: Ring gear 120h guide hole 117: Pin 118: Split groove 120: Turntable 120a: Gear 121a: Support arm 122:
Bearing 130: Fixed base 140: Reducer 141: Azimuth drive motor (drive means) 142: Worm 143: Worm wheel 144: Gear
145: Gear shaft 146: Support stand 147: Azimuth home position switch 148 Two rotary encoders 150: Reducer 151: Elevation drive motor (drive means) 152
: Worm 153: Worm wheel 154: Gear 155: Gear shaft (110-155; support mechanism) 157:
Rotary encoder 158: Elevation upper limit switch 159:
Elevation lower limit switch 160: Rotary joint 161.162: Cable Fig. 2b Fig. 20 Fig. 2d Fig. 20 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7b Fig. 8a Fig. 9b

Claims (1)

[Scope of Claims] A support mechanism that rotatably supports the antenna in the elevation direction and the azimuth direction on a moving body; a driving means that rotationally drives the antenna in the elevation direction and the azimuth direction; Receiver; first control for conically scanning the antenna in a set small area loop in the elevation direction and azimuth direction via the driving means, and setting the antenna attitude at a position where the reception level of the receiver is high during the conical scan; means; and a second control means for setting the small area loop to a wide one when the reception level of the receiver is low before the conical scan, and to a narrow one when the reception level is high. Attitude control device for antennas on mobile objects.