JPH1117445A - Antenna device and its adjustment method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an antenna device capable of simplifying installation adjustment and improving fixation strength after installation without degrading appearance after the installation, and to provide an adjusting method. SOLUTION: The entire reception unit 16 composed of a feed horn part 14 and a reception circuit part 15 is rotatably held by a clamp part 13. The reception unit 16 is arranged so as to match a middle point between the respective opening parts of two parallel waveguides formed at the feed horn part 14 and the focus of a parabolic reflection mirror 11. A rotation center axis is an axis passed through the middle point parallel to the waveguide. The elevation angles of the two satellites of a reception object are normally not equal and the elevation angle difference is different depending on the longitude of a reception spot or the like. The wave gathering position of radio waves from the respective satellites is different corresponding to the elevation angle difference. Then, the reception unit 16 is rotated and the adjustment of respectively matching the center part of the respective opening parts of the two waveguides at the feed horn part 14 to the respective wave gathering positions of the radio waves from the respective satellites is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antenna device for receiving satellite broadcasting and a method of adjusting the same, and more particularly to an antenna device for receiving radio waves from a plurality of satellites and a method of adjusting the same.

[0002]

2. Description of the Related Art In recent years, broadcast satellites (BSs)
Satellite broadcasting such as broadcasting using te) (hereinafter, referred to as BS broadcasting) and broadcasting using a communication satellite (CS: Communications Satellite) (hereinafter, referred to as CS broadcasting) are becoming widespread. In order to receive such a satellite broadcast, an antenna device including, for example, a parabolic reflector and a receiving unit arranged near the focal point of the reflector is generally used. Here, the receiving unit usually includes a feed horn as a waveguide for guiding the radio wave collected by the reflecting mirror to a rear radio wave / electric signal conversion unit and a reception signal converted by the radio wave / electric signal conversion unit. (A frequency conversion, amplification, etc.), and outputs the resulting signal to a BS tuner or the like.

Conventionally, a single beam antenna for receiving only one satellite broadcast has been generally used. However, recently, broadcast waves from a plurality of satellites launched at different positions are transmitted by a single antenna device. A multi-beam antenna capable of receiving has also been put to practical use. In this type of multi-beam antenna, a feed horn is arranged corresponding to each collection position of radio waves from each satellite by the reflecting mirror, and a receiving circuit unit is separately provided for each feed horn, and a signal from each satellite is provided. The radio waves are processed independently and transmitted to an indoor tuner. Here, the feed horn and the receiving circuit unit are usually configured as one receiving unit integrated in one-to-one correspondence, and such a receiving unit has the same number of receiving beams (number of receiving target satellites). They are arranged in the number. For example, in a dual beam antenna that receives radio waves from two satellites, the number of receiving units is two.
And these are arranged and fixed corresponding to the respective collection positions of the radio waves from the respective satellites.

Generally, a broadcasting satellite or a communication satellite is stationary at a predetermined longitude position above the equator. , Each satellite has the same elevation angle (apparent altitude with respect to the horizon). However, when viewed from a point that is not on the meridian passing through the midpoint, the elevation angles of the two satellites are not equal, and the elevation difference between the two varies depending on the longitude and latitude of the observation point. Specifically, as the distance from the meridian passing through the midpoint between the two satellites increases, the elevation angle difference changes in a direction to increase. Therefore, for example, when the antenna device is installed in various places in Japan, the position of collection of the radio wave from each satellite by the reflecting mirror changes according to the elevation angle difference of the satellite at the installation location, so that the best reception sensitivity is obtained. It is necessary to match the position of each receiving unit (especially feed horn) with the actual wave collection position.

Conventionally, the positioning of the feed horn corresponding to the elevation difference between the two satellites which differs depending on the receiving point is performed by rotating the entire reflecting mirror to adjust the position of the two feed horns fixed integrally therewith. The adjustment was made by adjusting the position (inclination from the horizontal arrangement position).

[0006]

As described above, in the conventional multi-beam antenna, the adjustment corresponding to the elevation angle difference between a plurality of satellites involves adjusting the entire antenna device including the reflector in parallel with the rotationally symmetric axis of the reflector. It was done by rotating around an important axis. For this reason, it is necessary to provide such a rotation mechanism in a portion that supports the entire antenna device (accurately, a portion that supports the reflector), and there is a problem that the structure becomes large and the weight increases. . In addition, since adjustment for rotating the entire antenna is required, construction work at the time of installation is not easy, and workability is not good. In addition, since this type of antenna device is usually installed on a veranda or a roof where the wind is strong, if the above-described rotation mechanism is provided in a portion where the entire antenna device is attached, the wind pressure is increased. There is a problem that the resistance to the risk may decrease. Furthermore, characters or symbols such as a manufacturer name or a product name are normally displayed on the reflector, but if the reflector is adjusted to be rotated, the characters or the like are installed in an inclined state. Therefore, there is a problem that appearance is not preferable.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to simplify the adjustment at the time of installation work and to improve the fixing strength after the installation, and to improve the appearance after the installation. An object of the present invention is to provide an antenna device that does not cause any trouble and a method of adjusting the antenna device.

[0008]

SUMMARY OF THE INVENTION An antenna device according to the present invention includes a reflector for reflecting radio waves from a plurality of satellites and collecting them at different positions, a converter for converting the radio waves into an electric signal, And a plurality of waveguides that are arranged at predetermined intervals corresponding to each other and guide each radio wave collected by the reflecting mirror to the conversion unit, and hold the whole of the plurality of waveguides rotatably about a predetermined axis. Holding means. here,
A plurality of waveguides are arranged such that the midpoint in the arrangement direction coincides with the focal point of the reflector, and the entirety is held rotatably about an axis passing through the focal point and parallel to the waveguide. It is preferred to do so.

A method for adjusting an antenna device according to the present invention includes a reflector for reflecting radio waves from a plurality of satellites and collecting them at different positions, a converter for converting the radio waves to an electric signal, and a method for each satellite. And a plurality of waveguides arranged at predetermined intervals and guiding each radio wave collected by the reflecting mirror to the conversion unit, wherein the entirety of the plurality of waveguides is Is held so as to be rotatable around the center, and by adjusting the entire rotation of the plurality of waveguides, adjustment is made so that each waveguide is adjusted to the collection position of the radio wave from the corresponding satellite.

In the antenna device or the method of adjusting the same according to the present invention, the entirety of the plurality of waveguides for guiding the radio waves collected by the reflecting mirror to the conversion unit is held rotatably about a predetermined axis. You. By rotating the plurality of waveguides around a predetermined axis, each of the waveguides is arranged corresponding to a position where a radio wave from a corresponding satellite is collected.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a schematic configuration of an antenna device according to an embodiment of the present invention. This antenna device 1 is configured as a dual beam antenna for receiving radio waves from two satellites S1 and S2 that draw a geosynchronous orbit on the equator while keeping a distance close to each other, as shown in FIG. 11, for example. For example, as shown in FIG. 12, it is used by being installed on the roof of a user's house, on a veranda, or the like. In the present embodiment, the satellites S1 and S2 are described as communication satellites that transmit CS broadcast radio waves, but are not limited thereto, and may be broadcast satellites that transmit BS broadcast radio waves. Where C
Linear broadcasting is used in S broadcasting, and circular polarization is used in BS broadcasting.

As shown in FIG. 1, this antenna device 1
Is configured as an offset-type antenna device in which radio waves are not obstructed by the receiving unit 16, and includes a parabolic reflecting mirror 11, which is a part of a paraboloid of revolution,
A clamp unit 13 is fixed near the focal point of the parabolic reflector 11 by an arm 12, and a receiving unit 16 is rotatably held by the clamp unit 13.
The receiving unit 16 is configured to include a feed horn section 14 and a receiving circuit section 15 called a normal converter formed integrally with the feed horn section 14.
A connector (not shown) is provided below the receiving circuit unit 15, and one end of the coaxial cable 17 is connected to the connector. The other end of the coaxial cable 17 is connected to an indoor tuner (not shown).

Here, the parabolic reflector 11 corresponds to the "reflector" in the present invention, and the clamp 13 corresponds to the "holding means" in the present invention.

An elevation adjusting mechanism 21 for adjusting the elevation of the parabolic reflector 11 is provided on the back side of the parabolic reflector 11.
Is attached. The elevation angle adjusting mechanism 21 is rotatable in the elevation direction around the fixing bolt 21c while being guided by the fixing bolt 21b inserted into the arc-shaped long hole 21a, and is fixed at an appropriate elevation angle position. , 21c to tighten the parabolic reflector 11
Can be fixed in that position. The elevation adjustment mechanism 21 is attached to an azimuth adjustment mechanism 22 for adjusting the azimuth of the parabolic reflector 11. The azimuth adjustment mechanism 22 is rotatable in the azimuth direction about the fixing bolt 22c while being guided by the fixing bolt 22b inserted into the arc-shaped long hole 22a, and is fixed at an appropriate azimuth position. By tightening the bolts 22b and 22c for use, the parabolic reflector 11 can be fixed at that position. The azimuth adjusting mechanism 22 includes a main body 23a.
And a fixing plate 23b provided opposite to the main body 23a.
Are connected to the fixing portion 23 configured to include: Then, the support of the veranda or the like is sandwiched between the main body 23a and the fixing plate 23b and tightened with the bolt 23c or the like, so that the entire antenna device can be attached to the support of the veranda or the like.

FIG. 2 is an enlarged view of the clamp unit 13 and the receiving unit 16 in FIG. 1, FIG. 3 is a view from the direction of arrow A in FIG. 2, and FIG. 4 is a view in FIG. This shows a state viewed from the direction of arrow B. 3 and FIG.
4 shows a state in which it is mounted. As described above, the receiving unit 16 includes the feed horn unit 14 and the receiving circuit unit 1.
5, the feed horn portion 14 includes a feed horn main portion 142 in which two adjacent waveguides 140a and 140b are formed in parallel with each other and a feed horn main portion 142. And a cap 144 for covering the front portion of the feed horn body 142 and the ring 143. Here, the waveguides 140a and 140b correspond to "a plurality of waveguides" in the present invention.

Openings 141a and 141b having a predetermined opening area are formed at the front ends (the side facing the parabolic reflector 11) of the waveguides 140a and 140b, respectively. Feed horn body 142 and ring 143
Is formed as an integral conductor such as a die-cast metal such as aluminum. However, both may be formed separately and connected. The feed horn main body 142 is rotatably held by the clamp 13 and is fixed to the clamp 13 at an arbitrary rotational position by a fixing screw (not shown). The rotation center axis of the feed horn main body 142 passes through the midpoint of the openings 141a and 141b, and
The axis is parallel to the axes 0a and 140b (hereinafter, referred to as a midpoint axis). This is a feature of the antenna device according to the present invention.

As shown in FIGS. 3 and 4, the feed horn body 142 is disposed such that the midpoint of the openings 141a and 141b coincides with the focal point F of the parabolic reflector 11. In this state, as shown in FIG. 13, radio waves from the satellites S1 and S2
At the opening 141a of the feed horn section 14,
Waves are collected in the vicinity of each central portion of 141b. FIG. 13 is a simplified view of the parabolic reflector 11 and the feed horn section 14 viewed from the direction of arrow D in FIG. 1 with the elevation angle and azimuth angle of this antenna device being adjusted to the directions of the satellites S1 and S2. It represents.

FIG. 5 shows a state in which the feed horn portion 14 is viewed from the front with the cap 144 removed in FIG. 3, FIG. 6 shows a section taken along line YY 'in FIG. 5, and FIG. 7 shows a section taken along line ZZ' in FIG. Is represented. As shown in these figures, the cylindrical portions of the waveguides 140a and 140b are each formed in a cylindrical shape with a mutual interval (center-to-center distance) L without interfering with each other. On the other hand, each of the openings 141a and 141b is formed so as to form a part of a funnel shape (conical shape) having an inclined surface with a predetermined inclination, but the mutual interval L between the waveguides 140a and 140b is equal to the opening. The openings 141a and 141b interfere with each other because they are formed smaller than the maximum diameter φ (hereinafter simply referred to as the opening diameter φ) of the portions 141a and 141b.
Therefore, portions of the openings 141a and 141b that interfere with each other are formed in a cut-out state, leaving the partition 146.

The distance L between the waveguides 140a and 140b
Depends on the relative distance between satellites S1 and S2 shown in FIGS. 11 to 13 (more precisely, the longitude difference between the stationary positions of the satellites), the aperture diameter and focal length of parabolic reflector 11, and so on.
L decreases as the longitude difference in S2 decreases. For example, JCSAT-3 where satellite S2 is located at 128 degrees east longitude
Assuming that the satellite S1 is JCSAT-4 which will be launched soon and is located at 124 degrees east longitude, the longitude difference between the two is only 4 degrees. Here, the parabolic reflector 11
Assuming that the aperture diameter of the F / D is reduced to, for example, about 40 cm and its focal length is set to, for example, about 20 cm, the F / D
The ratio between the focal length and the aperture diameter of the antenna is 0.5
The distance L between the waveguides 140a and 140b at this time is about 22 mm. On the other hand, in order to obtain the required reception sensitivity by such a small parabolic reflector 11, the aperture diameter φ of each of the openings 141a and 141b is 2.
It is considered necessary to exceed 5 mm. Therefore,
In this case, the openings 141a and 141b interfere with each other. However, the gap L and the opening diameter φ can be obtained by cutting out the portions where the openings 141a and 141b interfere with each other to form the shapes shown in FIGS. Can be simultaneously satisfied, and radio waves from two approaching satellites can be received with the required sensitivity using the small parabolic reflector 11.

Here, a preferred example of selection of the opening diameter φ of the openings 141a and 141b will be described. When the frequency of the received radio wave is, for example, 12.20 GHz to 12.75 GHz, the interval L is, for example, 21.7 mm, and the opening diameter of the parabolic reflector 11 is, for example, 40 cm, the opening 141 is formed.
a, 141b opening diameter φ is 21mm, 25mm, 28m
The experiment was performed with three settings of m. As a result, when the opening diameter φ is 25 mm or 28 mm as compared with the case where the opening diameter φ is 21 mm, 0.2 dB to 0.3 dB
Gain (gain) of about 0.2 dB to 0.4 d
A noise reduction effect of about B can be obtained, and the C / N (carrier / noise) difference of the two is 0.4 dB to
It improved by about 0.6 dB. Here, the opening diameter φ is 25 mm
Since the C / N difference was approximately the same between the case of 28 mm and the case of 28 mm, the amount of interference (notch amount) between the two openings 141a and 141b was small, and the amount of deformation from a circle was small.
It is more preferable to adopt the one of 5 mm.

The ring portion 143 cancels noise components coming in from directions other than the radio wave from the satellite and cancels the noise components from the openings 141a and 141b to the waveguides 140a and 140.
This is for preventing the noise from entering the inside of Ob. As shown in FIG. 6, the depth M of the groove inside the ring portion 143 is formed so as to be a quarter of the wavelength of the radio wave. Therefore, the radio wave R incident on the outside of the ring portion 143
1 causes a phase difference of a half of the wavelength when passing through the groove inside the ring portion 143, and this current is generated by a radio wave R2 incident on the feed horn body inside the groove. It cancels out with the current.
That is, the presence of the ring portion 143 reduces noise components and improves reception sensitivity.

The cap 144 shown in FIGS. 2 and 3
Is a non-conductor (eg, PE (polyethylene) or AES)
(A synthetic resin such as an acrylic resin) and is provided mainly for waterproofing, but is also used for the purpose of increasing the convergence effect of radio waves. For example, the entire cap 144 is formed of a material having a low dielectric loss tangent (loss tangent of dielectric constant; tan (ε ′ / ε ″), where ε ′ and ε ″ are real and imaginary parts of complex dielectric constant ε, respectively). At the same time, the inner portion is processed into a shape protruding in accordance with the shape of the openings 141a and 141b, and the above-mentioned protruding portion is arranged at an optimum position when the cap 144 is mounted on the feed horn portion 14. It is preferred to configure.
In this case, since the above-mentioned protruding portion can function as a lens, as a result, it is equivalent to an increase in the diameter of the openings 141a and 141b, and the reception sensitivity can be improved by improving the wave collecting effect.

FIG. 8 is an enlarged cross-sectional view taken along the line XX ′ of the receiving unit 16 and the clamp unit 13 shown in FIG. 3. FIG. 9 is a diagram showing the receiving circuit unit 1 from the direction of arrow C in FIG.
5 shows a state in which the user sees No. 5. Here, FIG. 8 also corresponds to the XX ′ section in FIG. In FIG. 8, the illustration of the cap 144 shown in FIG. 3 is omitted, in FIG. 9, a part of the cover plate 154 and the shielding member 153 shown in FIG. 8 are omitted, and in FIG. 8 and FIG. The illustration of the coaxial cable 17 shown in FIG.

As shown in FIGS. 8 and 9, the receiving circuit section 15 includes a housing 151 made of a conductive material,
1, a shielding member 153 made of a conductor disposed so as to cover a main part of the substrate module 152, and a lid plate made of a conductor for sealing the housing 151. 154. Here, the housing 151 is formed integrally with the feed horn main body 142, for example, as a die-cast metal such as aluminum. However, the present invention is not limited to this, and the two may be formed separately and connected.

A grounding pattern 152a (not shown in FIG. 9) is formed on the back side (the side from which radio waves arrive) of the substrate module 152, and is in contact with the waveguides 140a and 140b of the feed horn body 142. ing. A grounding pattern 152b patterned in accordance with the shapes of the waveguides 140a and 140b and a receiving electrode for receiving a linearly polarized light in the horizontal direction are provided on the surface of the substrate module 152 (opposite to the surface from which radio waves arrive). Horizontal electrode pattern 152c-
1, 152c-2, and vertical electrode patterns 152d-1, 152d-2 as receiving electrodes for vertical linear polarization. Each of these patterns is formed of a thin film conductor such as a copper foil. However, in FIG. 8, the thickness of each pattern is drawn to be thicker than actual.

Here, the horizontal electrode pattern 152c-1 and the vertical electrode pattern 152d-1 are connected to the waveguide 140a.
The horizontal electrode pattern 152c-1 converts a horizontal linearly polarized wave propagated through the waveguide 140a into an electric signal, and the vertical electrode pattern 152d-1 is a conductive electrode. This is for converting the vertical linear polarization propagated through the wave path 140a into an electric signal. On the other hand, the horizontal electrode pattern 152c-2 and the vertical electrode pattern 152d-2 are reception electrodes provided corresponding to the waveguide 140b, and among them, the horizontal electrode pattern 152c-2 is in the horizontal direction propagating through the waveguide 140b. Is converted into an electric signal, and the vertical electrode pattern 1
52d-2 converts the vertical linearly polarized wave propagated through the waveguide 140b into an electric signal. Here, the horizontal electrode patterns 152c-1 and 152c-2 and the vertical electrode patterns 152d-1 and 152d-2 correspond to the "converter" in the present invention.

The shielding member 153 includes the waveguides 140a, 14
0b, for blocking the radio wave transmitted through the board module 152, like the case 151, is formed by metal die-casting of, for example, aluminum or the like, and is provided with a ground pattern 152 from the front side of the board module 152.
It is fixed to the housing 151 by a screw (not shown) so as to make surface contact with only b. The cover plate 154 is provided for the housing 1.
51 is for sealing the inside to prevent rainwater from entering and for electromagnetically shielding, and is made of a conductor.

FIG. 10 schematically shows the circuit configuration of the board module 152. This board module 152
Includes a circuit called a converter that mainly performs frequency conversion and amplification of a received signal. Specifically, four receiving electrodes (horizontal electrode patterns 152c-1 and 152c-2 and vertical electrode patterns 152d-1 and 152d-2) for converting radio waves into electric signals, and a horizontal electrode pattern 152c-1 Or vertical electrode pattern 152d
−1, a switch 156b that switches so as to select one of the horizontal electrode pattern 152c-2 or the vertical electrode pattern 152d-2, and a switch 156.
a, 156b, a switch unit 157 for switching to select one of the outputs, a high-frequency amplifier circuit 158 connected to the output terminal of the switch unit 157, and a mixing unit connected to the output terminal of the high-frequency amplifier circuit 158. A circuit 159;
The mixing circuit 159 includes a local oscillation circuit 160 that supplies a local oscillation signal of a predetermined frequency to the mixing circuit 159, and an intermediate frequency amplification circuit 161 connected to an output terminal of the mixing circuit 159. The output terminal of the intermediate frequency amplification circuit 161 is connected to a connector 155 to which the coaxial cable 17 (FIG. 4, etc.) is connected.
The board module 152 is connected to the coaxial cable 17.
A stabilizing power supply 162 that supplies stable power to each of the above-described circuits based on a DC voltage (for example, about 15 V) supplied through the connector 155 is provided.

Switch sections 156a, 156b, 157
Performs a switching operation in response to a switching signal from a control unit (not shown), thereby selecting any one of the four receiving electrodes and connecting to the high-frequency amplifier circuit 158. The control unit outputs the switching signal in response to a received polarization selection command transmitted via a coaxial cable 17 from a tuner (not shown) installed indoors, for example. Has become. The high-frequency amplifier circuit 158 is a circuit for amplifying, for example, a 12-GHz band high-frequency signal received by the horizontal electrode pattern 152c-1 or the like as it is.
(A gallium arsenide field effect transistor) or the like, and is configured using an amplifier element having a very low noise. The mixing circuit 159 includes, for example, the 1
Heterodyne detection is performed on the high-frequency signal in the 2 GHz band and the local oscillation signal in the 11 GHz band supplied from the local oscillation circuit 160, and the intermediate frequency signal (IF) in the frequency band that can be transmitted by the coaxial cable 17, for example, the 1 GHz band
Signal). The frequency of the received high-frequency signal is, for example, 12.25 GHz to 12.75 GHz.
z, and the frequency of the local oscillation signal is, for example, 11.2 GHz
Then, the frequency of the IF signal is 1.05 GHz to 1.5
5 GHz. The intermediate frequency amplifying circuit 161 applies the coaxial cable 1 to the IF signal output from the mixing circuit 159.
Amplification is performed to a level necessary to compensate for signal attenuation when transmitting 7 and reduce image quality deterioration caused by a noise factor of a tuner (not shown).

Next, the operation and operation of the antenna device having the above configuration will be described.

First, a method of adjusting the antenna device will be described with reference to FIGS. This adjustment includes adjusting the rotation angle of the receiving unit 16 configured by integrating the feed horn unit 14 and the receiving circuit unit 15, adjusting the elevation angle of the entire antenna device including the parabolic reflector 11 and the receiving unit 16, Adjustment of the azimuth of the entire antenna device is included. Here, first, the reason why the rotation angle of the receiving unit 16 needs to be adjusted and the adjustment method thereof will be described.

Now, the satellites to be received are shown in FIGS.
Are the two satellites S1 and S2 shown in FIG. here,
As described above, for example, the satellite S2 is positioned above the equator 36000
JCSAT with geostationary orbit at 128 degrees east longitude at km height
Assuming that the satellite S1 is a JCSAT-4 having a geostationary orbit at 124 degrees east longitude at a height of 36000 km above the equator, for example, in Tokyo at about 140 degrees east longitude, these satellites S1 and S2 It appears to be stationary in the southwestern sky, as shown in Figure 12. Since these satellites are both located on the equator, when the two satellites are viewed from a point on the longitude line of the midpoint of the two satellites (here, 126 degrees east longitude), the elevation angle (horizontal line) of each satellite is Although the reference altitude angle becomes the same, the elevation angles β1 and β2 of the two satellites S1 and S2 as shown in FIG. 12 and FIG. β2 is not equal, and the elevation angle difference (β2-β1) between the two varies depending on the latitude and longitude of the observation point. For example, satellite S
The elevation angle difference changes in a direction to increase as the distance from the longitude of the midpoint of S1 and S2 increases. Specifically, as shown in FIG.
The elevation angle of the satellite S2 located at a longitude closer to the longitude (140 degrees in this case) of the installation point of the antenna device is larger than the elevation angle of the satellite S1 located at a farther longitude. In other words, the satellite S2 looks higher than the satellite S1. Therefore, for example, when the antenna device is installed in various places in Japan, the collection position of the radio wave from each satellite by the parabolic reflector 11 changes according to the elevation angle difference between the two satellites S1 and S2 at the installation location. In order to obtain the best receiving sensitivity, the receiving unit 1 is placed at each actual collecting position.
6, the two openings 141a and 141b need to be aligned.

In the present embodiment, the entire receiving unit 16 including the feed horn unit 14 is clamped by the clamp unit 13 in order to match the actual positions of the wave collection with the openings 141a and 141b. , Are held rotatably about the midpoint axis, and the feed horn portion 14 is rotated to open the
The center portions of the feed horns 1a and 141b are fitted together, and in this state, the feed horn portion 14 is fixed to the clamp portion 13 by a fixing screw (not shown) or the like. This is one of the features of the antenna device adjusting method according to the present invention. Since the rotation angle of the feed horn section 14 in this case is determined mainly by the longitude of the installation point of the antenna device, the rotation angle of each installation point is graduated in advance around the feed horn section 14 and the user can use this scale. The rotation of the receiving unit 16 may be adjusted according to the following.

FIG. 15 shows satellites S1 and S2 shown in FIG.
Represents a state after the rotation of the receiving unit 16 has been adjusted. This figure shows the parabolic reflector 11
Shows a state in which the receiving unit 16 is viewed from the side of. In this example, the entire receiving unit 16 (that is, the feed horn portion 14) is adjusted to a position where the whole receiving unit 16 (that is, the feed horn portion 14) is rotated clockwise by an angle α from the horizontal direction about a midpoint axis passing through the focal point F of the parabolic reflecting mirror 11. .

For example, in the case where the installation point of the antenna device is in Tokyo at about 140 degrees east longitude, the elevation angle β1, with respect to the satellites S1 and S2 (here, JCSAT-4 and JCSAT-3),
β2 (FIG. 14) is about 45.3 degrees and 46.7 degrees, respectively, and the elevation angle difference (β2−β1) in this case is about 1.4 degrees. Due to the presence of the elevation angle difference, the collection positions P1 and P2 of the radio waves from the satellites S1 and S2 by the parabolic reflector 11 are shifted up and down. In this case, the receiving unit 16 is moved by about 18 around the midpoint axis. When rotated clockwise by degrees, each of the wave collection positions P1 and P2 becomes the opening 141a, 14a.
1b are substantially at the center. That is,
In Tokyo, the rotation adjustment angle α of the receiving unit 16 is about 1
8 degrees.

After the rotation angle of the receiving unit 16 has been adjusted in this way, the elevation angle and the azimuth angle of the antenna device are adjusted. The elevation angle of the antenna device is adjusted by the elevation angle adjustment mechanism 21 in FIG. That is, the fixing bolt 21b inserted into the arc-shaped long hole 21a of the elevation adjusting mechanism 21 and the fixing port 21c serving as the rotation center are loosened, and the parabolic reflecting mirror 11 is previously set according to the latitude and longitude of the installation point. The parabolic reflector 11 is fixed by moving it to a predetermined elevation position and tightening the fixing bolts 21b and 21c there. The azimuth adjustment of the antenna device is performed by the azimuth adjustment mechanism 22 shown in FIG.
Done by That is, the fixing bolt 22b inserted into the arc-shaped long hole 22a of the azimuth adjusting mechanism 22 and the fixing 22c serving as the rotation center are loosened, and the parabolic reflecting mirror 11 is rotated.
Is moved to a predetermined azimuth position in accordance with the longitude of the installation point, and the parabolic reflector 11 is fixed by tightening the fixing bolts 22b and 22c. Further, the radio wave is actually received in this state, and the elevation angle and the azimuth angle are finely adjusted so that the reception state becomes the best.

Next, the operation of the antenna device will be briefly described.

The high-frequency CS broadcast waves respectively transmitted from the satellites S1 and S2 are reflected by the parabolic reflector 11 as shown in FIG.
Waves are collected near the center of each of 41a and 141b,
Further, the light is guided to the substrate module 152 in FIG. 8 by the waveguides 140a and 140b. In this case, the satellites S1,
The CS broadcast wave transmitted from S2 is two kinds of polarized waves in the horizontal direction and the vertical direction.

The high-frequency radio waves arriving at the substrate module 152 are transferred to the horizontal electrode patterns 152c-1 and 152c- provided on the front side of the substrate module 152.
2, are converted into high-frequency electric signals by the vertical electrode patterns 152d-1 and 152d-2, and are selectively input to the high-frequency amplifier circuit 158 shown in FIG. At this time, the control unit (not shown) determines which of the signals from the four electrode patterns is to be input to the high-frequency amplifier circuit 158 by the switch units 156a, 156b, and 157.
Select by switching.

In the case of linear polarization, the polarization direction does not always coincide with the horizontal or vertical direction, and the angle formed by the polarization direction with the horizontal or vertical direction (hereinafter referred to as polarization angle γ). Varies considerably with the latitude and longitude of the receiving point. For example, if the satellite S1 is 124
In the case of JCSAT-4 located in degrees, the polarization angle γ in Naha of Okinawa is about 7.4 degrees, while the polarization angle γ in Tokyo is as large as about 20.7 degrees. In the case of JCSAT-3 in which satellite S2 is located at 128 degrees east longitude, the polarization angle γ in Naha of Okinawa is about 0.6 degrees, while the polarization angle γ in Tokyo is about 15.9. Degree and big. On the other hand, each receiving electrode pattern (horizontal electrode pattern 152c-1,
152c-2, vertical electrode patterns 152d-1, 152
d-2) is normally created in accordance with the polarization angle γ of the received radio wave at a reference point (for example, Osaka) near the center of the usable area of the antenna (for example, in Japan). Therefore, if it is assumed that the receiver unit 16 is installed at a point other than the reference point with a constant inclination in the rotational direction of the receiving unit 16 (here, the same direction as in Osaka), as shown in FIG. Between the receiving electrode pattern and the polarization direction (for example, between the direction of the vertical electrode pattern 152d-1 and the vertical polarization direction H of the received radio wave), A difference (hereinafter, referred to as a polarization angle change amount Δγ) is generated, so that efficient radio / electric signal conversion cannot be performed, and the gain decreases. In particular, in a region near the boundary of the usable area (for example, Hokkaido or Kyushu), the polarization angle change amount Δγ becomes large, and the receiving sensitivity is extremely deteriorated.

It should be noted that the polarization direction of the received radio wave at the above-mentioned reference point (for example, Osaka) and the polarization direction of the received radio wave at another point (for example, Tokyo) within the receivable area. (That is, the polarization angle change Δ
γ) is the feed horn section 14 at the above-mentioned reference point.
Is substantially equal to the difference between the rotation adjustment angle α (FIG. 15) and the rotation adjustment angle α of the feed horn unit 14 at the reception point (hereinafter, referred to as the rotation angle change amount Δα). For example,
The polarization angles γ of the radio waves from the two satellites S1 and S2 are about 16.1 degrees and 10.7 degrees in Osaka and about 20.7 degrees and 15.9 degrees in Tokyo, respectively. The polarization angle change Δγ of the satellite is about 4.6 degrees, respectively.
5.2 degrees. On the other hand, the rotation adjustment angle α of the feed horn section 14 is about 13.4 degrees in Osaka and about 1 in Tokyo.
Since the angle is 8.3 degrees, the rotation angle change amount Δα is about 4.9 degrees. That is, the polarization angle change Δγ and the rotation angle change Δα
Is almost equal to Therefore, as shown in FIG. 15, when the feed horn unit 14 is adjusted to be rotated by an appropriate rotation adjustment angle α determined by the latitude and longitude of the receiving point, at the same time, the polarization angle change amount Δγ is The correction is also made automatically. For this reason, the deterioration of the gain due to the polarization error as described above hardly occurs, and the unnecessary reception signal level due to the mixing of the polarization in the direction intersecting with the intended polarization direction can be reduced. Good reception sensitivity can be ensured for the channel. Note that the proper rotation angle α and the polarization angle γ of the feed horn unit 14 do not exactly match each other, and the difference between the two slightly varies depending on the receiving point, but the range of the difference is limited in major regions in Japan. Since it is once or less, there is no practical problem.

The high-frequency amplifier circuit 15
The high-frequency reception signal input to 8 is amplified here at the same frequency and input to the mixing circuit 159. The mixing circuit 159 heterodyne-detects the high-frequency signal amplified by the high-frequency amplification circuit 158 and the local oscillation signal supplied from the local oscillation circuit 160, and outputs an IF signal having the difference frequency. To enter. The intermediate frequency amplifying circuit 161 amplifies the IF signal output from the mixing circuit 159 to a required level. The IF signal amplified in this way is sent to an indoor tuner (not shown) via the coaxial cable 17 and used for screen display in a television receiver (not shown).

As described above, in the antenna device according to the present embodiment, the entire receiving unit 16 including the feed horn portion 14 is held by the clamp portion 13 so as to be rotatable about the midpoint axis. In addition, it is possible to easily match the position of collection of radio waves from each satellite, which varies depending on the installation location of the antenna device, with the openings 141a and 141b. Moreover, not the entire parabolic reflector 11, but only the waveguides 140a and 140b (more precisely, only the receiving unit 16) is rotated, so that the heaviest parabolic reflector 11 is rotated.
A mechanism for rotatably holding the motor is not required, and resistance to strong winds is improved. Furthermore, since the parabolic reflector 11 itself is always at the reference position, it is also possible to eliminate a problem in appearance that the design of the characters and symbols drawn thereon is installed in an inclined state.

Further, in the antenna device according to the present embodiment, the feed horn section 14 having the two waveguides 140a and 140b and the receiving circuit section 15 are integrated into one receiving unit 16, so that a conventional receiving unit is provided. There is no need to prepare a number of receiving units corresponding to the number of receiving beams for each antenna device, and only a single receiving unit 16 needs to be prepared. Therefore, the number of parts is reduced, and the configuration of the apparatus is simplified. In addition, each of the plurality of receiving units is set to 1
In contrast to the conventional device which is arranged and fixed corresponding to each of the collecting positions of two reflectors, the antenna device uses only a single receiving unit 16, so that the positioning mechanism and the fixing mechanism are simplified, and the installation work is also easy. Becomes Furthermore, a common receiving circuit unit 1 corresponding to the two waveguides 140a and 140b
5 is provided, and the reception signals from the waveguides 140a and 140b are appropriately switched and processed by the reception circuit unit 15. Therefore, a single coaxial cable for connecting the reception unit 16 and the indoor tuner unit is provided. Sufficient and easy wiring. In addition, the provision of the ring portion 143 makes it possible to reduce noise.

Further, in the antenna device according to the present embodiment, each of the openings 141a, 141a of the waveguides 140a, 140b.
In the case where 41b interferes with each other, the openings 141a and 141b are formed so as to cut out the interfering portion of both, so that the conflicting demands to reduce the distance L between the two and at the same time increase the respective opening diameter φ. Can be satisfied at the same time. For this reason, the small parabolic reflector 11
, It is possible to efficiently separate radio waves from two approaching satellites and receive them with sufficient sensitivity.

Although the present invention has been described with reference to the embodiment, the present invention is not limited to this embodiment, and can be variously modified within an equivalent range. For example, in the above embodiment, the satellites S1 and S2 have been described as satellites for CS broadcasting, but the present invention is not limited to this, and can be applied to satellites for BS broadcasting. However, in this BS broadcast, circularly polarized waves are used. In this case, instead of the substrate module 152 shown in FIG. 9, a substrate having the receiving electrode patterns 152e-1 and 152e-2 as shown in FIG. The module 152 'is used. In this figure, the same parts as those in FIG. 9 are denoted by the same reference numerals. In this example, the waveguides 140a, 14a
0b, the receiving electrode patterns 152e-
1, 152e-2 are formed so as to extend in a direction inclined at a predetermined angle (for example, 45 degrees) from the vertical direction in +/- directions, respectively, and the grounding pattern 152b 'is formed in the receiving electrode pattern 152e. Patterning is performed so as to avoid -1, 152e-2. Other configurations are the same as those in FIG. Since circular polarization is used in BS broadcasting, there is no concept of a polarization error which is a problem in CS broadcasting, and the rotation of the receiving unit 16 is simply adjusted by the position of collection of radio waves from each satellite. Wave paths 140a, 1
It is performed only for alignment with 40b.

The two satellites are not limited to the same kind of satellites (ie, CS and CS, or BS and BS), and constitute an antenna device capable of receiving radio waves from different types of satellites (ie, CS and BS). Is also possible. In this case, a portion of the substrate module corresponding to the waveguide for receiving the radio wave from the CS is provided with, for example, the receiving electrode pattern (for example, the horizontal electrode pattern 152c-
1 and a vertical electrode pattern 152d-1), and a portion corresponding to a waveguide for receiving a radio wave from the BS is provided at a portion corresponding to the reception electrode pattern 15 as shown in FIG.
2e-2 or the like may be formed.

Further, in the antenna device according to the above-described embodiment, only one set of a circuit portion corresponding to a converter is mounted on the board module 152 provided commonly to the waveguides 140a and 140b. Although the circuit portion to be used is shared for the received radio waves from each satellite, the present invention is not limited to this, for example,
Two sets of circuit parts corresponding to the converter may be mounted on one board module, and these circuit parts may be allocated to processing of signals received from each satellite. further,
Two independent board modules each equipped with a circuit portion corresponding to a converter may be prepared, and each of these board modules may be allocated to processing of a signal received from each satellite.

In the antenna device according to the above-described embodiment, the two waveguides 140a and 140b are integrally formed as a part of the feed horn part 14, and one waveguide 140a and 140b is provided corresponding to these waveguides 140a and 140b. And a feed horn section 14 and a receiving circuit section 15.
Are configured as one receiving unit 16, but the present invention is not limited to this, and the waveguide and the receiving circuit unit are integrated one-to-one to form one receiving unit. Two such receiving units may be prepared, and each of these receiving units may be arranged so as to correspond to a received radio wave from each satellite. In this case, the center point between the waveguide openings of the receiving units and the focal point of the parabolic reflector 11 are arranged so as to coincide with each other. The two receiving units may be rotatably held as they are around the center of the two receiving units.

In the above embodiment, the dual beam antenna device capable of receiving radio waves from two satellites has been described. However, the present invention is not limited to this, and the present invention is not limited to this. It is also possible to apply to a multi-beam antenna device capable of receiving radio waves.

For example, when a triple beam antenna device capable of receiving radio waves from three satellites arranged close to one another at equal intervals above the equator is configured, as shown in FIG. 17, for example, as shown in FIG. Waveguides 140a ', 140b', and 140c 'for receiving radio waves of the same type are formed in a straight line, and an opening 1 is formed at each entrance.
41a ', 141b', 141c 'and a ring 143' around them to form a feed horn 1
4 '. Then, the three openings 141a ', 1
The feed horn section 14 'is arranged so that the midpoint of the arrangement direction of 41b' and 141c 'coincides with the focal point F of the parabolic reflector 11, and the waveguides 140a' and What is necessary is just to comprise so that the feed horn part 14 'can rotate about the axis parallel to 140b' and 140c '. Also in this case, three waveguides and one
One receiving unit may be provided by integrating one receiving circuit unit with another, or, as described above, the waveguide and the receiving circuit unit may be integrated on a one-to-one basis. One receiving unit may be configured, and three such receiving units may be prepared, and each of these receiving units may be arranged in correspondence with a radio wave received from each satellite. The same applies to the case where an antenna device corresponding to four or more satellites is configured.

[0052]

As described above, according to the antenna device according to the first or second aspect, or the method for adjusting the antenna device according to the third or fourth aspect, the wave collected by the reflecting mirror is obtained. Since the entirety of the plurality of waveguides that respectively guide each radio wave to the conversion unit is rotatably held about a predetermined axis, the entirety of the plurality of waveguides is rotated about the predetermined axis. Accordingly, adjustment for arranging the respective waveguides at the collection positions of the radio waves from the corresponding satellites can be easily performed, and the installation operation is simplified. Further, since the waveguide portion is rotated instead of rotating the entire reflecting mirror, a mechanism for rotatably holding the heaviest reflecting mirror becomes unnecessary, and the resistance to strong winds is improved. Further, since the reflecting mirror itself is always at the reference position, there is an effect that the conventional appearance defect that the design of the character and the like drawn on the reflecting mirror is installed in an inclined state can be solved.

In particular, according to the antenna device of the second aspect or the method of adjusting the antenna device of the fourth aspect, the plurality of waveguides are arranged such that the midpoint in the arrangement direction coincides with the focal point of the reflecting mirror. At the same time, the whole was held so as to be rotatable around the axis passing through the focal point and parallel to the waveguide, so that the adjustment for arranging each waveguide at the collection position of the radio wave from each satellite was accurately performed. And can receive radio waves from each satellite with high sensitivity. Moreover, when receiving a satellite broadcast using linear polarization, by adjusting the rotation of a plurality of waveguides, automatically,
Since the polarization error generated due to the longitude and the like of the receiving point is also corrected, there is an effect that the receiving sensitivity is further improved.

[Brief description of the drawings]

FIG. 1 is a perspective external view showing an entire antenna device according to an embodiment of the present invention.

FIG. 2 is an enlarged perspective view illustrating a clamp unit and a receiving unit of FIG. 1;

FIG. 3 is a front view of a clamp unit and a receiving unit.

FIG. 4 is a side view of a clamp unit and a receiving unit.

FIG. 5 is a front view of a feed horn section in the receiving unit.

FIG. 6 is a partial cross-sectional view of a feed horn section in the receiving unit.

FIG. 7 is another partial cross-sectional view of the feed horn section in the receiving unit.

FIG. 8 is a cross-sectional view of the entire clamp unit and the receiving unit.

FIG. 9 is a rear view of the receiving unit.

FIG. 10 is a block diagram illustrating a circuit configuration of a board module in the receiving unit.

FIG. 11 is an explanatory diagram showing a geosynchronous orbit of a satellite.

FIG. 12 is an explanatory diagram showing the position of a satellite as viewed from the ground.

FIG. 13 is an explanatory diagram for explaining how radio waves from two satellites are collected by a parabolic reflector to a feed horn unit.

FIG. 14 is an explanatory diagram for explaining an elevation angle difference between two satellites.

FIG. 15 is a diagram illustrating a state where the rotation of the receiving unit is adjusted.

FIG. 16 is a rear view illustrating another configuration example of the board module in the receiving unit.

FIG. 17 is a front view illustrating another configuration example of the feed horn section in the receiving unit.

[Explanation of symbols]

11: parabolic reflector, 12: arm, 13: clamp part, 14: feed horn part, 15: receiving circuit part, 16
... Reception unit, 17 ... Coaxial cable, 21 ... Elevation angle adjustment mechanism, 22 ... Azimuth angle adjustment mechanism, 23 ... Fixed part, 140
a, 140b, 140a ', 140b', 140c '...
Waveguide, 141a, 141b, 141a ', 141
b ', 141c' ... opening, 142 ... feed horn body, 143 ... ring, 144 ... cap, 151 ...
Housing, 152 ... board module, 152 c-1, 152
c-2: Horizontal electrode pattern, 152d-1, 152d-
2. Vertical electrode pattern, 152e-1, 152e-2 ...
Receiving electrode pattern, 153: shielding member, 154: lid plate,
S1, S2 ... satellite

Claims (4)

[Claims] 1. A reflecting mirror for reflecting radio waves from a plurality of satellites and collecting them at different positions, a conversion unit for converting the radio waves into an electric signal, and arranged at a predetermined interval corresponding to each of the satellites. A plurality of waveguides for guiding the radio waves collected by the reflecting mirror to the conversion unit; and a holding unit for holding the entirety of the plurality of waveguides rotatably about a predetermined axis. An antenna device characterized by the above-mentioned. 2. The plurality of waveguides are arranged such that a midpoint in the arrangement direction coincides with the focal point of the reflecting mirror, and the whole of the plurality of waveguides has an axis passing through the focal point and parallel to the waveguide. The antenna device according to claim 1, wherein the antenna device is rotatably held as a center. 3. A reflecting mirror that reflects radio waves from a plurality of satellites and collects them at different positions, a conversion unit that converts the radio waves into an electric signal, and is arranged at a predetermined interval corresponding to each of the satellites. A method for adjusting an antenna device, comprising: a plurality of waveguides for guiding each radio wave collected by the reflecting mirror to the conversion unit, wherein the plurality of waveguides are rotated around a predetermined axis. A method for adjusting an antenna device, wherein the antennas are held so as to be capable of adjusting the position of each of the waveguides to a position at which a radio wave from a corresponding satellite is collected by rotating the plurality of waveguides as a whole. 4. The plurality of waveguides are arranged so that a midpoint in the arrangement direction coincides with the focal point of the reflecting mirror, and the whole is centered on an axis passing through the focal point and parallel to the waveguide. The method for adjusting an antenna device according to claim 3, wherein the antenna device is rotatably held.