JPH01261005A - Antenna system - Google Patents

Abstract

PURPOSE:To improve the responsiveness against a rapid attitude change in a mobile body such as an automobile and to secure excellent communication by detecting the relative movement of a radio source with respect to an antenna so as to control the attitude of the antenna. CONSTITUTION:Each radiation lobe of 1st, 2nd and 3rd reception antennas 10a, 10b and 20a is kept in parallel, and a plane including the radiation lobe of the 1st and 2nd reception antennas 10a, 10b and a plane including the radiation lobe of the 1st and 3rd reception antennas 10a, 20a are kept perpendicular and the antennas are supported to be movable freely in a 1st direction and a 2nd direction orthogonal thereto. Then the direction of a radio wave source is obtained by a phase difference of the reception signal between the 1st reception antenna 10a and the 2nd reception antenna 10b and a phase difference of the reception signal between the 1st reception antenna 10a and the 3rd reception antenna 20a to control the attitude of each antenna. Thus, excellent communication is secured and the antenna system is made suitable for the installation to a small moving body such as an automobile.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a receiving antenna device, and for example, to an antenna device for receiving satellite broadcasting on a mobile object such as a car.

[Prior art]

Since the realization of satellite communications, there has been a trend to receive radio waves from satellites not only in fixed buildings but also in moving objects such as automobiles. In order to receive weak radio waves from satellites, a high gain antenna, that is, an antenna with sharp directivity is required.

“For this reason, when attempting to receive radio waves from satellites in a mobile object such as a car, attitude control of the antenna becomes a problem, and a number of related technologies have been introduced.

One of them is a satellite communication antenna device disclosed in Japanese Patent Publication No. 61-282'44. Simply put, this device has a communication antenna and a rate gyro installed on a flywheel-type stabilizer, and maintains the initially set antenna attitude in the communication direction.

[Problems with conventional technology]

However, the high-gain antenna for receiving weak radio waves from satellites is relatively large and heavy. is required. For this reason, it is not very suitable for installation in small moving objects such as automobiles.

Furthermore, small moving objects such as automobiles undergo rapid changes in posture due to their maneuverability. In order to maintain the initial posture for a long time against these drastic posture changes, a large rate gyro with large inertia is required, which also makes this device suitable for installation in small moving objects such as automobiles. That's probably the reason why there isn't one.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide an antenna device that ensures good communication and is also suitable for installation in a small moving object such as a car.

[Structure of the invention]

In order to achieve the above object, in the present invention.

1st. The second and third receiving antennas are arranged so that their respective radiation lobes are kept parallel, and the plane containing the radiation lobes of the first and second receiving antennas is perpendicular to the plane containing the radiation lobes of the first and third receiving antennas. the phase difference between the received signal of the first receiving antenna and the received signal of the second receiving antenna, and the received signal of the first receiving antenna. The configuration is such that the direction of the radio wave source is determined from the phase difference between the received signal of the third receiving antenna and the received signal of the third receiving antenna, and the attitude of each antenna is controlled.

In addition, the means for supporting the first antenna group including the first receiving antenna and the second receiving antenna and the means for supporting the second antenna group including the third antenna group are made independent to reduce inertia in the first direction, Make the drive mechanism lighter and smaller.

[Effect]

According to this, the antenna attitude is controlled by detecting the relative movement of the radio wave source with respect to the antenna, thereby eliminating the need for a large, heavy flywheel or a large rate gyro with large inertia.

Furthermore, when the means for supporting the first antenna group including the first receiving antenna and the second receiving antenna and the means for supporting the second antenna group including the third receiving antenna are made independent, the inertia in the first direction is This not only makes the mechanism that drives in this direction lighter and smaller, but also reduces the inertia when driving these together, improving responsiveness to severe changes in attitude of a moving body such as an automobile.

Good communication can be ensured.

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

〔Example〕

FIG. 1a shows a plan view of an in-vehicle satellite broadcast receiving antenna device embodying the present invention as an example, and FIG. 1b shows a front view thereof. The mechanical configuration of the embodiment device will be explained with reference to these drawings.

What is shown at 10.20 in FIG. 1a and FIG. 1b, respectively, is a planar antenna unit having the same specifications. These antenna units each have two antenna units, as shown as 10a, 10b or 20a, 20b in FIG.
It consists of an antenna section with a radiation lobe (main lobe 2 and below is the same) with a half-value angle of approximately 7°.

A shaft 11 is fixed to the center of the antenna unit 10, and a shaft 21 is fixed to the center of the antenna unit 20.

The support member 30 is pivoted at the center to the pedestal 40,
V-shaped arms 31 and 32 are formed at both ends of the horizontally extending arms and are bent vertically and extend upward. One end of the V-shaped arms 31 and 32 is connected to the antenna unit 10.
The other end is the axis 11 of the antenna unit 20,
They each support each other. In this support, the V-shaped arms 31 and 32 hold the axes 11 and 21 parallel and
The vertical height of shaft 11 is maintained higher than shaft 21.

A sector gear 22 is attached to one end of the shaft 21 of the antenna unit 20.
is fixed. This sector gear 22 is connected to the support member 3
It meshes with a drum-shaped worm 51 fixed to the output shaft of an elevation drive unit 50 installed at 0. Moreover, the shaft 11 of the antenna unit 10 and the antenna unit 2
Both ends of the shaft 21 of 0 are connected by link mechanisms 52 and 53 with the respective surfaces kept parallel. In other words,
The drum-shaped worm 51 is driven by the elevation motor Me (see FIG. 2a) provided in the elevation drive unit 50.
When the antenna units 10 and 2 are energized in the forward and reverse directions, the antenna units 10 and 2
0 rotates up and down in the elevation direction about the respective axes 11 and 21 while maintaining the parallelism of each plane, that is, the parallelism of the radiation lobes of each antenna section. In the embodiment, the rotation speed is about 120''/see, and the rotation range is limited to about 60 degrees, and the upper and lower limits are detected by limit switches.

On the back surfaces of the antenna units 10 and 20, there are circuit assemblies 13a, 13b, or 2 including a BS converter, an in-phase synthesis circuit, a gyro unit, etc., which will be described later.
3a and 24a are installed.

A slip ring unit 60 is coupled to the central shaft 33 of the support member 30, and a wheel gear (not shown) is fixed to the lower end. This wheel gear meshes with an hourglass-shaped worm 71 fixed to the output shaft of an azimuth drive unit 70 provided on the pedestal 40. Therefore, when the azimuth motor Ma (see FIG. 2a) provided in the azimuth drive unit 70 forces the hourglass worm 71 in the forward and reverse directions, the support member 30 and the antenna units IO and 20 mounted thereon are integrated. Rotates left and right in the azimuth direction. In the example device, this rotation speed is approximately 180°/sec.

Each of the elements described above is covered by a radome RD and placed on the roof of an automobile (not shown).

In FIG. 2a, the direction of the broadcasting satellite is detected by signals received by each antenna section of antenna units 10 and 20 to control the attitude of the device.

Also shown is a block diagram illustrating the configuration of an electric circuit that demodulates and outputs received signals. Before entering into the explanation of this figure, the principle of detecting the direction of the broadcasting satellite will be explained with reference to FIGS. 3a and 3b.

FIG. 3a schematically shows the relationship between the antenna sections 10a and 10b of the antenna unit 10 and radio waves from a broadcasting satellite. In this case, since the distance L1 between the antenna sections 10a and 10b is very small compared to the distance to the broadcasting satellite, it can be considered that radio waves arrive at each antenna section in parallel and with equal intensity. However, since radio waves have periodicity, the phase difference between the received signals occurring in each antenna section due to the difference in reach cannot be ignored. Now, if we consider that there is a broadcasting satellite in a direction shifted by an angle Φ from the normal in a plane including the radiation lobes of antenna sections 10a and 10b, and that antenna section 10a receives a signal of cos ω, then the reception of antenna section tab The signal is C05C1l (t+Q 1 /c)=c
osc+> (t+ L 1 sinΦ/c)=cos
(ωt, + (L) L 1 sinΦ/c)...
...(1) becomes. This equation (1) is expressed by the antenna section 10a.
This means that the phase of the received signal of the antenna section 10b is advanced by ωL 1 sin Φ/C compared to the received signal of the antenna section 10b. However, ω is the angular frequency of the radio wave, t is the time, and C is the propagation speed of the radio wave.

In other words, since ω+L1 and C are known, the phase difference ωL1s between the received signals of antenna sections 10a and 10b
By detecting inΦ/C, the declination angle Φ of the broadcasting satellite in the plane containing the radiation lobes of antenna sections 10a and 10b can be determined. In this embodiment, since the distance L1 between the antenna sections 10a and 10b is an integral number n1 times a half wavelength, this phase difference is n1πsinΦ.

Similarly, FIG. 3b schematically shows the relationship between the antenna section 10a of the antenna unit 1o, the antenna section 20a of the antenna unit 20, and radio waves from a broadcasting satellite.

Now, if we consider that there is a broadcasting satellite in a direction shifted by an angle θ from the normal in a plane including the radiation lobes of antenna sections 10a and 20a, and that antenna section 10a receives a signal cosωL, then the reception signal of antenna section 20a is is, cosω(Q2/c) = cosω(t+L25in(θ-Δ)/C)=
cos (ωt+ (11L 25in(θ−Δ)/c
)...=...(2). This equation (2) shows that the received signal of the antenna section 20a is ωL2sin(θ−Δ)/c compared to the received signal of the antenna section 10a.
This means that the phase advances by . However, L2 is the distance between antenna sections 10a and 20b.

That is, since ω+L2+C and Δ are known, the phase difference ωL between the received signals of antenna sections 10a and 20a
By detecting 2sin(e-Δ)/c, the declination angle θ of the broadcasting satellite in the plane containing the radiation lobes of antenna sections 10a and 20a can be determined. Note that in this embodiment, the antenna sections 10a and 2
Since the distance L2 from 0a is an integer n2 times the half wavelength, this phase difference is n2π5in(e-Δ).

The description continues with reference to FIG. 2a. In this, the two-dot chain line 80 indicates the elements mounted on the support member 30, including the antenna unit 10.20, the elevation drive unit 50. B provided in circuit assemblies 13a and 13b installed on the back side of antenna unit IO
S converters 14a, 14b, tuners 15a, 15b
and in-phase synthesis circuit 16. Also, a BS converter 24a provided in circuit assemblies 23a and 23b installed on the back surface of the antenna unit 20.

24b, tuners 25a, 25b, in-phase synthesis circuit 26.
27. A voltage controlled oscillator (hereinafter referred to as vCO) 28 and a gyro unit 29 are included.

Each antenna section 10a, 10b, 20a and 20b
The feeding points of the BS converters 14a, 14b, and
24a or 24b. Each BS converter converts a signal of approximately 12 GHz transmitted from a broadcasting satellite into a signal of approximately 1.28 GHz, and connects the corresponding tuner 15a, 15b.

25a or 25b. Each tuner has a VC
The first intermediate frequency signal is applied from O28, and the signal given from the corresponding BS converter is approximately 402.78
Convert to Ahz. A control voltage for the VCO 28 is provided via a slip ring 61 provided in a slip ring unit 60 from a channel selector 94 provided in a television set 90 installed in the vehicle.

The outputs of the tuners 15a and 15b are sent to the in-phase synthesis circuit 16.
The outputs of tuners 25a and 25b are respectively applied to in-phase synthesis circuit 26.

The configuration of the in-phase combining circuit 16 will be explained with reference to FIG. 2b.

A signal given from the tuner 15a is input from the terminal A, and is distributed by the splitter 1601 to the amplifier 1602 and the splitter 1603, and further to the splitter 1603.
The signal is then distributed to multipliers 1604 and 1605. Further, the signal given from the tuner 15b is inputted from the terminal B and sent to the splitter 1 by the 90° phase shift splitter 1606.
607 and 1608, splitter 160
8 is distributed with a 90' phase shift. splitter 1
607 distributes the input signal to multipliers 1604 and 1613, and splitter 1608 distributes the input signal to multipliers 1605 and 1614.

Now, the signal applied to terminal A is cosωt, and the signal applied to terminal B is cosωt, which has a phase lead of φ.
s(ω+φ), the output of the multiplier 1604 is cosωj X cos(ωt+φ) = (cos(2ωt+φ) + cosφ)/2
......(3). This output signal has a harmonic component removed in a low-pass filter 1609, and a high frequency component is removed in a high-frequency terminator 1611, and is converted into a signal having only a DC component, that is, (cosφ)/2, and is applied to a multiplier 1613. It will be done.

In the multiplier 1613, this signal is multiplied by the signal cos(ωL+φ) given from the terminal B, and the output is c
os((11t+φ) X (cosφ)/2=
(cosω+cos(ωt+2φ)) /4
...(4) is given to the combiner 1615.

On the other hand, in the multiplier 1605, the signal cos ω given from the terminal A and the signal cosω given from the terminal B
A signal obtained by shifting (ω + φ) by 90°, that is, -5
Multiply by in (ωt+φ). Its output is CO8ω
X (5in(ω+φ))=−(sin(
2ωt+φ) 10sinφ)/2 (5), and the low-pass filter 1610 and high-frequency terminator 1
At 612, the high frequency component is removed and the DC component is obtained.

That is, only -(sinφ)/2 is extracted.

The multiplier 1614 multiplies this signal by 90° shifted signal at terminal B, -sin (ω + +φ), and outputs the result.

(-3in(ωt, 1φ)) X ((sinφ)
/2) = (cosωt, -cos (ω+2φ
)) /4 ......(6) to combiner 16
Give to 15.

In the combiner 1615, the output of the 1 multiplier 1613 and the 16
14 and outputs (cosωt,)/2. This output is further amplified in amplifier 1616 and then applied to combiner 1617. A combiner 1617 combines the output of this amplifier 1617 with the output of the amplifier 1602.
, and outputs 2cosωt.

Note that the coefficient of the output 2 cos ωt of the combiner 1617 does not represent the amplitude component, but can be considered to mean that two signals, that is, the signals given from the terminals A and B are combined.

The configuration of the in-phase synthesis circuit 26 is the same as that of the in-phase synthesis circuit 16, except that one additional low-pass filter 2618 is provided, as shown in the second cli4. In this case, the output signal of the tuner 25a applied to the terminal C and the output signal of the tuner 25b applied to the terminal R are combined. According to the above, when the output signal of the tuner 15a is set to cos ω, the output signal of the tuner 25a becomes cos (ω 700) which has a phase lead of θ, and the output signal of the tuner 25b becomes (θ+
It becomes cos (ωL10+φ) whose phase is advanced by φ). Therefore, the combiner 2617 has two combined signals 2co
Outputs s (ω700).

Low-pass filter 261 added to in-phase synthesis circuit 26
8 is the output of the multiplier 2605, i.e. -(sin(
2ωt+20+φ)+sinφ)/2 to DC component -5
inφ is extracted and given as an azimuth error signal to the control unit 100 (FIG. 2a) via the slip ring 63 provided in the slip ring unit 60.

The outputs of these in-phase synthesis circuits 16 and 26 are applied to an in-phase synthesis circuit 27 (FIG. 2d).

The configuration of the in-phase combining circuit 27 is the same as that of the in-phase combining circuit 26, as shown in FIG. 2d. Here, the output of the in-phase synthesis circuit 16, ie, 2cosωt, and the output of the in-phase synthesis circuit 26, ie, 2cos(ωL10), are combined to generate a composite signal 4cosωL. however,
As before, this coefficient is
This can be taken to mean that the outputs of 25a and 25b are combined.

Furthermore, the low-pass filter 2718 of the in-phase synthesis circuit 27 extracts the DC component -5inθ from the output of the multiplier 2705, that is, -5in(2ω and 10) -5inθ,
The elevation error signal is supplied to the control unit 100 (FIG. 2a) via a slip ring 62 provided in a slip ring unit 60.

Referring again to FIG. 2a, the output of the in-phase synthesis circuit 27 is provided to a demodulation circuit 91 provided in the television set 90 via a non-contact type coupling transformer Trs provided in the slip ring unit 60. The demodulation circuit 91 demodulates the signal given from the in-phase synthesis circuit 27 and outputs an image to the CRT 92 and audio to the speaker 93, respectively. Further, the AGC signal used in automatic gain adjustment is branched and given to the control unit 100.

The gyro unit 29 has degrees of freedom in the azimuth direction and the elevation direction, and the relative deviation in each direction is detected by rotary encoders 29a and 29e.
4.65 to the control unit 100.

The elevation drive unit 50 includes an elevation motor Me, a rotary encoder Ee coupled to the output shaft of the elevation motor Me, and limit switches SWu and SWd that detect upper and lower limits in the elevation direction. The elevation motor Me and the rotary encoder Ee are connected to the servo motor driver 102 via a slip ring 68 or 69 provided in the slip ring unit 60, and a limit switch S W u
and SWd are respectively connected to the control unit 100 via a slip ring 66 or 67 provided in the slip ring unit 60.

On the other hand, the azimuth drive unit 70 includes an azimuth motor M
a and a rotary encoder Ea coupled to the output shaft of an azimuth motor Ma, which are connected to a servo motor driver 101.

Servo motor drivers 101 and 102 are connected to control unit 100.

When the main switch 95 provided in the television set 90 is turned on, the power supply unit 11
6 to which a predetermined voltage is supplied from 0, and power supply unit 1
A ventilation fan 120 in the radome RD is connected to the radome RD, and ventilation cooling in the radome RD is performed at the same time as the main switch 95 is turned on.

The control unit 100 receives an azimuth error signal and an elevation error signal provided from the in-phase synthesis circuits 26 and 27, and an A signal provided from the demodulation circuit 91.
The servo motor driver 101 and 1
The control unit 100 controls the attitude and control of the antenna units 10 and 20 by controlling the motors Ma and Me via the motors 02. The attitude control to be performed will be explained.

When the main switch 95 is turned on and a predetermined voltage is supplied to each part of the control unit 100, St (same meaning below 2 indicating the number attached to the step in the flowchart)
Initialize memory, registers, flags, etc. at
In S2, initial values are set in registers used to search for broadcast satellites. In other words, in the initial state, the search range is set to the entire range, so the lower limit value E12min or upper limit value EQmax in the elevation direction is set to the registers EΩd and EQu, which are used to limit the search range in the elevation direction, respectively. The reference value 0 or the maximum value A z 1aax in the azimuth direction is set in registers AzQ and Azr used for limitation, respectively.

83 to S7 are a loop waiting for input from the keyboard terminal 103. In this loop.

When the data indicating the current location of the vehicle is input, the elevation angle of the broadcasting satellite can be specified to some extent, so in S4, data limiting the search range in the corresponding elevation direction is set in registers EQd and EQu, and When the data indicating the azimuth angle is input, the azimuth of the broadcasting satellite can be specified to some extent, so in S6, data limiting the search range in the corresponding azimuth direction is set in registers AzQ and Azr.

When a start instruction is input from the keyboard terminal 103, the loop is started, and in S8, the value of the register AzQ indicating the left limit of the search range in the azimuth direction is stored in the register Az, and the lower limit of the search range in the elevation direction is stored in the register EQ. The value of the register End shown in FIG. This causes the servo motor driver 101 to drive the azimuth motor Ma.
The servo motor driver 102 energizes the elevation motor Me to position the support member 30 in the direction indicated by the value of the register Az, and the servo motor driver 102 energizes the elevation motor Me to position the antenna units 10 and 20 at the elevation angle indicated by the value of the register Efi. Since positioning is to be performed, the time required for this is waited at SIO.

In Sll-S30, a search for a broadcasting satellite is performed while monitoring the reception level indicated by the AGC signal.

In the search, first, in S16, register E1 is
2 and the value of the register EQu, that is, the upper limit value in the elevation direction. If the value of register EQ has not reached this upper limit value, register E
The value of Q is incremented by 1 and the value is transferred to the servo motor driver 102 in sis. This causes the servo motor driver 102 to drive the elevation motor Me.
is energized to change the elevation angle of antenna units lO and 20 to l
Since the step is updated upward, a predetermined time is waited in S19.

When the value of the register Efi reaches the upper limit value by repeating the above, the flag F2 is set in S20, and the value of the register Az is compared with the value of the register Azr, that is, the right limit value in the azimuth direction, in S21. If the value of register Az has not reached this right limit value, the value of register Az is incremented by 1 in S22, and the value is transferred to the servo motor driver 101 in S23. As a result, the servo motor driver 101 energizes the azimuth motor Ma to update the azimuth of the support member 30 to the right by one step, and therefore waits for a predetermined time in S24.

This time, since flag F2 is set, the process proceeds to 825 and below, and the antenna is decremented by 1 until the value of register EQ reaches the value of register EQd, that is, the lower limit value in the elevation direction. The elevation angles of units 10 and 20 are updated downward by one step.

When the value of the register EΩ reaches the lower limit value, the flag 29 is reset in 829, and the azimuth of the support member 30 is updated rightward by one step in steps 329 and subsequent steps.

In other words, in this search process, register A z
Search for a broadcasting satellite while raster scanning the range limited by the values of Q * A z r g E Q d and Eflu. If a broadcasting satellite is not found in this search process, the process proceeds from S21 to 330, and after displaying the unreceivable status on the display provided on the keyboard terminal 103, the process returns to S3. Also, keyboard terminal 10
When a stop instruction is input from step 3, the search process is immediately terminated and the process returns to step S3.

If a broadcasting satellite is found in the above search process and the reception level stored in the register exceeds a predetermined level V, the process proceeds from 313 to 831 and tracking process is performed.

At 331, flags F1 and F3 are checked. Since the flag F1 is initially reset, this is set in S32, and then the flag F3 is reset.

In S33, based on the azimuth error signal (azimuth direction phase difference data φ, elevation direction phase difference data 0 based on the elevation error signal, azimuth direction gyro data gθ and elevation direction gyro data gφ are read. After that, in S34, the gyro data g and g are set in the register Gθ or Gψ, respectively, and in S35, the deviation of the azimuth direction and elevation direction of the broadcasting satellite with respect to the current antenna attitude indicated by the phase difference data φ and θ is determined. Set the angle data in the register Φ or θ, respectively.

At 336, the value of register Φ is added to register Az, and the value of register θ is added to register E12. However, the value of register Az is modulo Azmaz, and when the value of register Az exceeds Azmax in this addition, it becomes the value subtracted from it.

In S37, servo motor drivers 101 and 10
2, transfer the values of register Az and register EQ to S
After waiting for a predetermined time in step 38, the process returns to Sll.

The above steps are repeated to track the broadcasting satellite, but if the car goes into a tunnel or behind a building during that time, the reception level drops. At this time, when the reception level becomes lower than the predetermined level VO, the tracking process is temporarily interrupted in S13,
Proceed to 314 and below.

In S14, flag F1 is checked, but since this flag was set when S32 was passed, the process proceeds to S39 and flag F3 is further checked. Immediately after the tracking process is interrupted, the flag F3 is reset, so the process proceeds to 340, where the flag F3 is set and the timer T for measuring the time period during which the reception level continues to decrease is cleared and started.

In S41, gyro data gθ in the azimuth direction
and reads gyro data gφ in the elevation direction.

Since the registers Gθ and Gψ store the gyro data immediately before the reception level drops, the difference between the gyro data gθ and the value of the register Gθ and the difference between the gyro data gφ and the value of the register Gψ are , respectively, correspond to the deviation in the azimuth direction or the elevation direction of the current antenna attitude with respect to the antenna attitude immediately before the reception level decreases. Therefore, in S42, this difference is obtained, and in S49, the declination data in the azimuth direction or the elevation direction of the current antenna attitude with respect to the antenna attitude immediately before the reception level indicated by the difference decreases is set in the register Φ or θ, respectively. . Note that the sign (-) in the equation shown in S43 means that data that resists the relative deviation of the antenna attitude is set.

After this, the process proceeds to S36, but the following explanation will be omitted since it has been described above.

That is, if the reception level drops below the predetermined level VO during tracking of the broadcast satellite, the antenna attitude immediately before that point is maintained using the gyro data.

If the reception level exceeds the predetermined level VO before the value of the timer T exceeds the predetermined time To, steps S13 to S31. S
The process proceeds to step 32 and restarts the above-mentioned tracking process, but if the reception level has not recovered by then, the process proceeds from step 344 to 345 and below.

In S45, flags F1 to F3 are reset, and in S4
In step 6, for the subsequent search processing,
Data that limits the search range is set in registers Azr, AzQ, EQd, and EQu, respectively. In this case, since the azimuth direction depends on the azimuth angle of the car, set the search range around the entire circumference (set the maximum value Azmax in register Azr and the reference value 0 in register AzQ), but in the elevation direction, The search range is set based on the value of the EQ register indicating the elevation angle of the antenna unit at that time.

Thereafter, in step 847, a display on the keyboard terminal 103 indicates that reception is not possible, and the process returns to S3.

Note that during each of the above processes, the keyboard terminal 103
When a stop instruction is input, each process is immediately terminated in Sll.

Return to S3.

In the above embodiment, when there is no reception, the attitude of the antenna is controlled using gyro data, but this control may also be performed using, for example, a geomagnetic sensor, an angle sensor, or the like.

〔Effect of the invention〕

As explained above, according to the present invention, the antenna attitude is controlled by detecting the relative movement of the radio wave source with respect to the antenna. Gyro is no longer needed.

Furthermore, as explained in the embodiment, if the receiving antenna is divided into a plurality of groups, the inertia in the first direction, that is, the elevation direction in the embodiment, is reduced.
Not only is the mechanism that drives in this direction lighter and more compact, but the inertia when driving them together is also reduced, which improves responsiveness to rapid changes in the attitude of moving objects such as cars, and improves communication. can be secured.

[Brief explanation of the drawing]

FIG. 1a is a plan view of an in-vehicle satellite broadcast receiving antenna device embodying the present invention as an example, and FIG. 1b is a front view thereof. FIG. 2a is a block diagram showing the configuration of the electric circuit of the embodiment device, and FIGS. 2b, 2c, and 2d are block diagrams showing some details thereof. FIGS. 3a and 3b are explanatory diagrams for explaining the principle of detecting the direction of a broadcasting satellite. FIGS. 4a, 4b, and 4c are flowcharts showing the operation of the control unit 100 shown in FIG. 2a. 10.20: Planar antenna unit lO: (first antenna group) 20: (second antenna group) 10a, 10b, 20a, 20b: antenna section 10a: (first receiving antenna) rob: (second receiving antenna) 20a : (Third receiving antenna) 11.21 : Axis 22 : Sector gear 13a
, 13b, 23a, 23b: circuit assembly 14a
, 14b, 24a, 24b: BS converter 15a
, 15b, 25a, 25b: Tuner 16.26,2
7: In-phase synthesis circuit (in-phase synthesis means) 26: (first phase difference detection means) 27: (second phase difference detection means) 28: Voltage controlled oscillator 29: Gyro unit 30
: Support member 31, 32: V-shaped arm 33;
Central axis 40: Pedestal 50: Elevation drive unit (first w7A moving means) 51: Drum-shaped worm 52, 53: Link mechanism 30, 52, 53: (supporting means, first and second supporting means) 60 Nisslip ring Units 61 to 69; spring 70; azimuth drive unit (second drive means) 71: drum-shaped worm 90: television set 91: demodulation circuit 92: CRT 93: speaker
94: Channel selector 95: Main switch 100: Control unit (control means) 101.1
02: Servo motor driver 103: Keyboard terminal 110: Power supply unit 120: Ventilation fan RD Niradome Ma: Azimuth motor Me: Elevation motor Ea, Ee: Rotary encoder Trs: Non-contact coupling transformer Voice 42 K East 4b diagram

Claims (4)

[Claims] (1) First, second and third receiving antennas; the first,
The radiation lobes of the second and third receiving antennas are kept parallel, and the plane containing the radiation lobes of the first and second receiving antennas is perpendicular to the plane containing the radiation lobes of the first and third receiving antennas. support means for supporting the first, second, and third receiving antennas so as to be movable in a first direction and a second direction perpendicular thereto;
a first driving means for driving the second and third receiving antennas in the first direction; a second driving means for driving the first, second and third receiving antennas in the second direction; a first phase difference detection means for detecting a first phase difference signal corresponding to a phase difference between a received signal and a received signal of the second receiving antenna; a received signal of the first receiving antenna and a received signal of the third receiving antenna; a second phase difference detection means for detecting a second phase difference signal corresponding to the phase difference between the first and second driving signals; An antenna device comprising: control means for controlling energization of each of the means; (2) The antenna according to claim 1, further comprising in-phase combining means for in-phase combining received signals of at least two of the first, second, and third receiving antennas. Device. (3) A first antenna group including a first receiving antenna and a second receiving antenna; supporting the first antenna group so as to be movable in a first direction while keeping radiation lobes of the first and second receiving antennas parallel; a first support means; a second antenna group including a third receiving antenna; keeping the radiation lobe of the third receiving antenna parallel to the radiation lobes of the first and second receiving antennas; a second support means for supporting the second antenna group movably in the first direction while keeping a plane including the radiation lobes of the antenna perpendicular to a plane including the radiation lobes of the first and second receiving antennas; a first driving means for driving each of the first and second antenna groups in a first direction; a third supporting means movably supporting the first and second antenna groups, the first and second supporting means, and the first driving means in the second direction; a second driving means for driving; a first phase difference detection means for detecting a first phase difference signal corresponding to a phase difference between a reception signal of the first reception antenna and a reception signal of the second reception antenna; a second phase difference detection means for detecting a second phase difference signal corresponding to the phase difference between the received signal of the antenna and the received signal of the third receiving antenna; and a radio wave based on the first and second phase difference signals. An antenna device comprising: control means for determining the direction of a source and controlling energization of each of the first and second drive means. (4) The antenna according to claim (3), further comprising in-phase combining means for in-phase combining received signals of at least two of the first, second, and third receiving antennas. Device.