JPH0349302A - Film sheet diffraction ring antenna - Google Patents

Abstract

PURPOSE:To facilitate the antenna installation, to reduce the installation space and to reduce the effect of the meteorological effect by forming an antenna with a diffraction ring and a reception pickup part arranged at its focal position and fitting the diffraction ring onto the surface of the film with back living of adhesives. CONSTITUTION:The antenna is made of a film 2 provided with a diffraction ring 1a to one side with back side lining of an adhesive layer and a reception pickup section 3 is arranged to nearly a focal position of the diffraction ring 1a. The diffraction ring 1a is made of a metal and formed by adhering a metallic foil shaped like the diffraction ring in advance onto the film sheet 2 by the laminate or the vapor-deposition or the like. The shape of the diffraction ring 1a is designed in response to the operating condition, and the position of a satellite 7 in the embodiment has an elevating angle of nearly 38 deg. with respect to a focus F of the diffraction ring 1a arranged to a glass window 8 and the position is on a prolonged line tying the diffraction ring 1a and the focus F of the diffraction ring, then the diffraction ring 1a is drawn with a scale of 1/18.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a satellite broadcast receiving antenna, and particularly to a film sheet type diffraction ring type antenna that is easy to install.

[Conventional technology]

Conventionally, a parabolic antenna, a microstrip array antenna, or the like has been used as an antenna for receiving satellite broadcasting. As shown in FIG. 1T, the parabolic antenna is equipped with a paraboloid of revolution reflector 11 and a primary radiator 12.
-The next radiator 12 is a parabolic reflector of revolution 1! It is located at the focal point of the

- In the parabolic antenna configured in this way, radio waves transmitted from the satellite are reflected by the paraboloid of revolution reflector (1) and input to the primary radiator 12. Note that the reference numeral 1 in Fig. 17
3 indicates a BS converter.

On the other hand, a microstrip array antenna is a planar antenna with a layered structure, as shown in FIG. 18 (perspective view) and FIG. 19 (enlarged view of main parts), in which resonant conductors are assembled into a strip array Strip board 1
A branch circuit and a matching circuit are constructed on 6.

The symbol +5 in FIG. 18 indicates a dielectric material.

[Problem to be solved by the invention]

By the way, with the conventional satellite broadcast receiving antennas as described above, installation sometimes requires foundation work, as well as adjustment of the elevation angle and azimuth angle of the antenna, which poses the problem of requiring time and effort to install. be. In particular, parabolic antennas for satellite broadcast reception are susceptible to the effects of wind because of their structure, which has a large wind pressure load, and the wind pressure shifts the elevation and azimuth angles of the antenna, resulting in an extremely low reception level. Furthermore, there is a problem in that the characteristics of the antenna are easily affected by weather conditions, such as the reception level being reduced due to snow accumulation on the opening of the primary radiator of the parabolic antenna or the reflecting mirror.

Microstrip array antennas for satellite broadcast reception have a thin planar structure, so they are resistant to wind pressure and snow damage. Since the configuration is such that power is supplied to the element, there is a problem in that conductor loss and dielectric loss are large.

Furthermore, since the conventional satellite broadcast receiving antenna has a three-dimensional structure, there is a problem in that it requires a large installation space both when installed outdoors and indoors.

The present invention aims to solve these problems.
An antenna is composed of a diffraction ring and a receiving pickup section placed at its focal point, and the diffraction ring is attached to the surface of a film with an adhesive layer formed on the back side to facilitate antenna installation and installation. The purpose of the present invention is to provide a film sheet-type diffraction ring type antenna that takes up less space and is less susceptible to weather conditions.

[Means to solve the problem]

Here, to explain the diffraction ring, generally speaking,
In the radio wave propagation path at the receiving point, concentric Fresnel zones are formed, and adjacent ones have a difference in propagation path length by half a wavelength, and these interfere with each other in opposite phases, causing the electric field at the receiving point to be It's weakening. Therefore, every other 7
By shielding the Lennel zone and removing the anti-phase electric field, it is possible to increase the electric field at the receiving point. This is called the diffraction ring theory.

To give a concrete example, in Fig. 1, the receiving antenna A
An annular conductive plate B (diffraction ring) is installed at an appropriate position in front of the receiving antenna to increase the electric field strength near the receiving antenna, thereby increasing the receiving input. In addition, Part I
Arrow C in the figure indicates the direction of radio wave transmission.

Now, as shown in Fig. 16, if the electric field at point P (x, y, 0) of a plane wave traveling perpendicular to the X2 plane is Eo, then this electric field causes the point Q (0, 0, d) to The electric field dE generated at is:

Here, ds is a minute area, and by integrating this over the entire xZ plane, the electric field E at point Q is calculated, that is, the following equation is obtained.

Further, as shown in FIGS. 15 and 16, when the diffraction ring B is arranged and its inner radius is R1 and its outer radius is R1, the following results are obtained: Stone 1. If it is selected to satisfy "+d" - d error λ (λ is the wavelength of the radio wave), the electric field E at point Q is ・2
π E@-3Eoe -' A ', and the received electric field at point Q is three times the original, that is, 10d
It can be seen that B increases.

In this way, the received electric field at a certain receiving point can be increased by the action of the diffraction ring.

The present invention aims to obtain a diffraction ring type antenna suitable for a satellite broadcast receiving antenna using this diffraction ring, and the film sheet type diffraction ring type antenna according to claim 1 includes: A metal or dielectric diffraction ring is provided on the surface or in the form of a sandwich, and an adhesive layer is formed on one surface of the film, and a receiving pickup section is disposed approximately at the focal point of the diffraction ring. It is characterized by the fact that it has been accomplished, and
The film sheet type diffraction ring type antenna described in
A metal or dielectric diffraction ring is provided on the surface or in the form of a sandwich, and an adhesive layer is formed on one side of the film, and the proximal end is attached to the center of the diffraction ring on the surface of the film. It is characterized by comprising a thread having a length corresponding to the focal length of the diffraction ring, and a reception pickup section disposed approximately at the focal position of the diffraction ring.

[For production]

In the above-described film sheet type diffraction ring antenna of the present invention, the electric field strength of the receiving pickup section disposed at the focal point of the diffraction ring is reduced by the action of the metal or dielectric diffraction ring attached to the film sheet surface. Since the film sheet can be attached to a window glass or the like, the antenna can be easily attached, no space is required for the antenna, and the focal point of the diffraction ring antenna can be easily found.

〔Example〕

EMBODIMENT OF THE INVENTION Hereinafter, a film sheet type diffraction ring type antenna will be described as an example of the present invention with reference to the drawings.

1 to 9 show a first embodiment of the present invention.
The figure is a schematic diagram, Figure 2 is a front view of a film sheet to which a diffraction ring is attached, Figure 3 is a front view of a film sheet to which another example of the diffraction ring shown in Figure 2 is attached, and Figure 4 is a front view of a film sheet to which a diffraction ring is attached. A sectional view taken along the line IV-IV in Fig. 2, and Fig. 5 a cross-sectional view taken along the arrow V in Fig. 3.
-V arrow sectional view and Figure 6.7.9 are both explanatory diagrams of the mathematical formula that leads to the pattern of the diffraction ring. It is a front view.

The diffraction ring 11 of this embodiment is made of metal, and is formed by pasting a metal foil formed into a diffraction ring shape on the film sheet 2 by laminating or vapor deposition, or by pasting it onto the film sheet 2. It is formed by etching metal foil into a diffraction ring shape. Further, as shown in FIGS. 3 and 5, the diffraction ring 11 of this embodiment can be formed by forming the film sheet 2 and the diffraction ring li to the same size, or by forming the diffraction ring 11 on both sides with the film sheet 2. It is also possible to make a sandwich-like structure by sandwiching the two.

In the 7 concentric Renel zones formed on the radio wave propagation path at the transmitting and receiving points, adjacent zones have a propagation path length difference of half a wavelength, so they are in opposite phases, and these interfere with each other, increasing the electric field strength at the receiving point. However, the diffraction ring 11 of this embodiment is designed to remove the opposite phase electric field and increase the electric field at the receiving point by shielding adjacent Fresnel zones.

The shape of the diffraction ring 11 is designed according to the conditions of use, and FIG.
degrees, and the diffraction ring 11 and the same ring 1! focus of F
The diffraction ring 1 is drawn on a scale of 1/18 assuming that it is an extension of the straight line connecting the . Also,
FIG. 8 shows that the angle of elevation of the position of the satellite 7 from the focal point F of the diffraction ring 11 disposed on the window glass 8 is about 38 degrees, and the diffraction ring 11 and the same ring 1! The diffraction ring 11 is drawn on a scale of 1/11 assuming that the angle (azimuth angle) with respect to the straight line connecting the focal point F is 45 degrees.

Note that the patterns of these diffraction rings 11 are obtained as follows.

That is, in FIG. 9, it is assumed that the diffraction ring is on a plane perpendicular to the Z-axis, and the satellite 7 is located at an angle of - from the diffraction ring.

Therefore, consider a plane S perpendicular to the propagation direction of radio waves from the satellite, as shown in FIG.

Then, the sum of the distance from this plane S to a certain point P on the glass where the diffraction ring is installed and the distance from that point P to the focal point 0 is the distance from the plane S to the focal point O with λ
. Find the locus of point P that satisfies the condition of the diffraction ring that the distance is equal to or less than the sum of /2.

First, an equation for a plane S including a point Q (X,,Y,,Z,) is found.

Here, I OQ I − (x, ”+y−+z, Lee L
1L''-L/cos θ, the elevation angle of the satellite is θ, and the angle of the satellite from the diffraction ring is -, then the coordinates of points A, B, and C are respectively point A (L'/cos 11. 0. O) =
(L'/cosme・cosl.

0.0) Point B (0, O, L/5iol ・cosd) Point C (0
, L/sin θ, 0).

Also, if the formula for the plane S to be found is ax+by+cz=1, the plane S includes points A, B, and C, so a0L/cos
Me”C@Sθ-1・-a-coslIlcosθ/Lb
-L/cosθ-1,', b=siaθ/LC-L/5
iHj 4cosθl11 ・'-c-siaI*c
osθ/Lpa・Plane S is cosd・cosd・x+sinθ・y+cosI
It can be expressed as sin θ・z=L.

Next, if the surface where the diffraction ring is located is the xy plane of Z-F,
Point P (x, y,
The distance D1 to F) is the distance from the focal point F (0,0,0) to the point P (x, y + F) on the trajectory, which is D*-(x”+y”10F”) .

From the conditions of the diffraction ring L ten x λ. /2) D, +D.

, °, kx (λo/ 2 +cos yl #co
sθ−x+5iaoQy 0sia d・cosd・F
)! 〉x2+y20F2 (where k is an integer) 7 From the Renell ring condition, the inside of the ellipse with k<1 is in phase, l≦k (within the ellipse of 2 is out of phase, and the inside of the ellipse with 2≦k<3 is in phase. are in phase.

The second ring 1 & obtained by substituting θ-31' and d-90' into this calculation formula is shown on a scale of 1/18.
This calculation formula also includes θ-38°, 1-45
FIG. 8 shows, on a scale of 1/18, the value l! obtained by substituting ``.

In addition, in both cases, λ. −2, Sc+*.

An adhesive is applied to one surface of the film sheet 2, and the metal diffraction ring 11, which is bonded to a window glass or the like and integrated with the film sheet 2, can be attached to the glass window 8 or the like. Then, the focal position of the diffraction ring 11 [F
In order to pick up the radio waves whose electric field strength has been concentrated and increased by the first diffraction blowfish, a reception pickup section 3 is disposed to form an antenna.

This reception pickup section 3 is composed of a radiator 4 and a converter 5, and - for boat fishing, the radiator 4 is integrated with the converter 5. The reception pickup section 3 is supported by a stand 6 whose angle and height are adjustable. In FIG. 1, the radiator 4 has a horn structure, but it may also be structured as an array of spirals, dipoles, strip lines, slots, etc.

As mentioned above, a film sheet type diffraction ring antenna has a metal diffraction ring on a thin film that transmits radio waves, and this film sheet can be easily attached to a window glass, etc. Since the receiving pickup section is arranged at the focal point of the diffraction ring, it is easy to install the antenna, the installation space is reduced, and the antenna characteristics are not affected by weather conditions. At the same time, by reducing the number of components and making manufacturing easier, manufacturing costs can be significantly reduced, making it possible to supply an inexpensive satellite receiving antenna.

Next, a film sheet type diffraction ring type antenna as a second embodiment of the present invention will be described.

FIG. 10 is a front view thereof, FIG. 11 is a vertical cross-sectional view taken along arrows -■ in FIG. 8, and FIG. 12 is a cross-sectional view similar to FIG. 11 in the case of a modified example.

The diffraction ring of this embodiment differs from that of the first embodiment described above in that the diffraction ring lb is formed of a dielectric material. Note that the diffraction ring 1b may be formed by protruding from the dielectric substrate 11, as shown in FIG.

By making the diffraction ring lb made of a dielectric material in this way, in addition to obtaining substantially the same functions and effects as those of the first embodiment described above, the dielectric material has a slow wave effect due to its properties. In the Fresnel zones formed in the radio wave propagation path at the transmitting and receiving points, the phases of adjacent Fresnel zones, which are in opposite phases to each other, can be delayed by half a wavelength to bring them into phase, further increasing the electric field at the receiving point by about 3 dB. It becomes possible.

Next, a film sheet type diffraction ring type antenna as a third embodiment of the present invention will be explained.

The second figure is a schematic diagram.

The film sheet type diffraction ring type antenna of this embodiment is different from those of the first and second embodiments described above. This is the point where a thread 9 having a length connecting the positions is attached.

In the film sheet type diffraction ring type antenna having such a configuration, the focal point F position of the diffraction ring 1 can be determined by the thread 9 extending from the center 0 of the diffraction ring 1, so it is possible to determine the installation position of the reception pickup section 3. Easy to determine.

〔Effect of the invention〕

As detailed above, the film sheet type diffraction ring antenna of the present invention provides the following effects and advantages.

(1) By gluing the film sheet to a window glass, etc., a metal diffraction ring integrated with the film sheet can be attached to the window glass, etc., so it can be used for foundation work to install an antenna, or for viewing the satellite in the desired direction. There is no need to adjust the elevation and azimuth angles of the system, making installation easier.

(2) The receiving pickup section can be installed indoors, so
There is no influence of wind pressure or snow damage, and there is no influence of weather conditions on antenna characteristics.

(3) The metal diffraction ring and reception pickup section are provided independently from each other, and the diffraction ring is used by being attached to window glass, etc., so a space is required to arrange the reception pickup section. Unlike conventional satellite receiving antennas, the antenna does not require a large space for installation, and therefore the antenna installation space can be significantly reduced.

(4) Since the installation position of the receiving pickup section can be determined by the thread extending from the center of the diffraction ring, the focal point position can be easily determined.

(5) The number of components is significantly smaller than that of conventional satellite receiving antennas, and the diffraction ring attached to the film sheet and the reception pickup section are independent of each other. This makes manufacturing easier, and the reduction in the number of manufacturing parts and the ease of manufacturing reduce manufacturing costs, making it possible to supply inexpensive satellite receiving antennas.

Note that since the radio waves received by the film sheet type diffraction ring propagate in free space to be picked up by the receiving pickup section, there is no need to consider dielectric loss.

[Brief explanation of drawings]

Figures 1 to 9 show a film sheet type diffraction ring type antenna as a first embodiment of the present invention. Figure 1 is a schematic diagram thereof, and Figure 2 is a front view of the film sheet to which a diffraction ring is attached. , FIG. 3 is a front view of a film sheet to which a diffraction ring of another example shown in FIG. 2 is attached, FIG. 4 is a sectional view taken along the rV-IV arrow in FIG. -■A cross-sectional view in the direction of the arrows, and Figure 6.7.9 are both explanatory diagrams of the mathematical formula that leads to the pattern of the diffraction ring. Figure 8 is the front view of the film sheet on which a diffraction ring with a pattern different from that in Figure 2 is attached. 10.11. Figure H shows a film sheet type diffraction ring type antenna as a second embodiment of the present invention, Figure 10 is a front view thereof, and Figure 11 is a vertical cross-sectional view taken along the line ■-■ in Figure 10. , FIG. 12 is a sectional view similar to FIG. 1I in the case of a modified example, FIG. 13 is a schematic diagram showing an antenna of a film sheet type diffraction ring as a third embodiment of the present invention, and FIG. ．． Figure I5.16 are all diagrams explaining the principle of a diffraction ring antenna, Figure 17 is a perspective view of a conventional parabolic antenna, Figure 11 is a perspective view of a conventional microstrip antenna, 2 Figure 19 is a diagram of Figure 1S. It is an enlarged view of part A.

Claims (2)

[Claims] (1) A film on which a metal or dielectric diffraction ring is provided on the surface or in the form of a sandwich, and an adhesive layer is formed on one surface, and a receiving pickup section disposed approximately at the focal point of the diffraction ring. A film sheet type diffraction ring type antenna characterized by comprising: (2) A film in which a metal or dielectric diffraction ring is provided on the surface or in the form of a sandwich, and an adhesive layer is formed on one surface, and a proximal end is placed in the center of the diffraction ring on the surface of the film. A film sheet type comprising a thread having a length corresponding to the focal length of the diffraction ring to which the diffraction ring is attached, and a receiving pickup section disposed approximately at the focal position of the diffraction ring. Diffractive ring antenna.