JPS62260404A - Waveguide line - Google Patents

Abstract

PURPOSE:To attain the effective feeding by arranging an intermediate plate in a waveguide space so that the impedances between the waveguide spaces partitioned by the intermediate plate are made equal and providing a branch waveguide into a conductive space. CONSTITUTION:The cross section shape of corners C1-C3 of a waveguide space S including respectively feeding power detour gaps D1-D3 are formed all as semi-cross sectional shape of a regular octagon, then the reflection of the feeding power at the corners C1-C3 is prevented sufficiently. Further, an intermediate metallic plate 6a and 6b, 6c are provided to a position so that the impedances Z1-Z3 in the conduction spaces S1-S3 are made equal, e.g., at a position dividing the metallic plates 1 and 2 into three. Thus, the impedance among the conductor spaces S1-S3 is matched and further effective feeding is attained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a waveguide line suitable for use in a broadcasting antenna or the like, and particularly to a circular waveguide line.

[Conventional technology]

As a conventional circular waveguide line, there is one as shown in Fig. 11.12, and this circular waveguide line has a power radiation opening a formed on one side, which is arranged so as to be spaced apart from each other and face each other. A waveguide space e is formed inside the pair of metal plates S and c, and a peripheral wall d made of gold that connects the peripheral edges of these metal plates bvc.
is formed, and the circumference r! is formed within nne during this waveguide. ! f with d
An intermediate metal plate g is provided so as to leave a gap f for detouring the feeding power at the periphery fjid, thereby concentrating the feeding power toward the medium heat part in the waveguide space e as shown by the arrow Pf from the circumference fjid. A proposal has been made to make this possible.

htJ inside't11-19F7 mountain Ma81. I+r;? I
&hjJ3su&, 1.1 is the outer conductor of the coaxial line, 11
2 is an internal conductor of the coaxial line, i is a terminating resistor, j is a conductor matching plate, and shows a part of the corner of the waveguide space C including the gap r.

[Problem that the invention seeks to solve]

However, in the conventional circular waveguide, the intermediate metal plate g
Since impedance matching between the waveguide spaces partitioned by is not usually taken into account, there is a problem that feeding power cannot be extracted efficiently.

Furthermore, the conventional circular waveguide has the problem that the antenna cannot be made large.

The present invention aims to solve these problems.
The purpose of the present invention is to provide a waveguide line that achieves impedance matching between the waveguide spaces partitioned by medium-tm metal plates so that feeding power can be effectively extracted and the antenna can be made larger. do.

[Means for solving the problem, α]

For this reason, the waveguide line of the present invention includes a waveguide space surrounded by a metal wall, and an intermediate plate disposed in the waveguide space with a gap for detouring the feeding power left between the peripheral wall and the waveguide space. The waveguide space is provided with a power feeding portion connected to a power feeding opening shaped like 11t, and the waveguide space is partitioned by the intermediate plate. The intermediate plate is disposed within the waveguide space so that the impedance of the skin space arm is equalized, and a branch waveguide is provided within the waveguide space.

Further, the waveguide line of the present invention includes a waveguide space surrounded by a metal wall, an intermediate plate disposed in the waveguide space with a gap for detouring the feeding power between the peripheral wall thereof, and the above-mentioned intermediate plate. It is equipped with a power feeding part connected to a power feeding opening formed in the waveguide space,
In order to achieve impedance matching between the waveguide spaces partitioned by the intermediate plate, a matching body having a desired impedance is provided near the connection between the waveguide spaces (including the indirect a part), and It is characterized in that a branch waveguide is provided within the waveguide space.

[For production]

In the first waveguide of the present invention described above, the feeding power introduced into the waveguide space from the feeding section is branched by the branching waveguide, and the branched feeding power is released from the waveguide space to the outside. Ru.

In the second waveguide of the present invention described above, the feeding power introduced into the waveguide space from the feeding section is impedance matched by the matching body, and branched by the branching waveguide, and the branched feeding power is is emitted from the waveguide space to the outside.

〔Example〕

Examples of the present invention will be described below with reference to the drawings.
Figures 1 to 7 show a parallel (Christmas tree) type coaxial circular waveguide line when applied to a large antenna as a first embodiment of the present invention, and Figure 1 is a central vertical perspective view of the same, m2 Figure 3 is a graph showing its reflection coefficient characteristics, Figure 4 is a graph showing its internal characteristics, and PIS5 is a graph showing its power density characteristics along the radial direction of the upper space. , Fig. 6.7 all show modified examples thereof, and Fig. 6 is a sectional view of the main part thereof.
Figure tpJ8.9 shows a serial coaxial circular waveguide line when applied to a large antenna as a second embodiment of the present invention, and Figure Pt58 is a central vertical perspective view of the same.
The figure is a longitudinal cross-sectional view of the center, and Figures 110(a) to (1+
) are longitudinal cross-sectional views of main parts showing the matching body in the modification, and in each figure, the previously described reference numerals indicate substantially the same parts.

As shown in Fig. 1.2, in the first embodiment, a pair of metal disks 1゜2 are arranged so as to be spaced apart from each other and face each other, and one metal disk @1 has a power radiation source. A plurality of slots (or slits) 1a serving as openings are formed concentrically or spirally.

Further, the other metal disk 2 is formed with a power feeding opening 2a that is connected to a coaxial line 3 serving as a power feeding section.

A metal peripheral wall 4 is provided to connect the peripheral edges of these metal discs 1 and 2.
and the metal peripheral wall 4, its interior and this waveguide space S
Inside, a circular intermediate metal plate 6a and an annular intermediate metal plate 6b parallel to the metal disk 1.degree. ! ! A circular intermediate metal plate 6 is provided with a gap DI-D 2 for detouring the power supply left between the circular intermediate metal plate 6b and the circular intermediate metal plate 6b.
c is a gap between the intermediate metal plate 6b and the feeding power bypass;
These intermediate metal plates 6a to 6
c, the waveguide space S is divided into three lower waveguide spaces S, and an upper waveguide space sit and an intermediate waveguide space S forming a branch waveguide.

Further, the upper waveguide space S2 is an annular upper waveguide space S2.
2a, and a circular upper waveguide space S2b disposed inwardly from the upper waveguide space Set.

The intermediate metal plate 6c and the intermediate metal plate 6b are attached to the metal disk 1 by a terminating resistor 7 (this is disposed at the center of the disk) and an annular terminating resistor 7'' (this is disposed at the terminating resistor). (disposed on the circumference around the resistor 7), or via an insulating plate etc. in the middle,
Furthermore, the mounting location is selected appropriately.

Further, the intermediate metal plate 6a is attached to the intermediate metal plate 6c via the metal peripheral wall 4'.

In the waveguide space S1, a conical matching body 5 made of metal and having a tapered surface of about 45° is disposed with its top facing downward from the opening 2a. That is, the bottom portion of the matching body 5 is attached to the intermediate metal plate 6a concentrically with the intermediate metal plate 6a, so that the top portion of the matching body 5 is located on the central axis of the opening 2a.

Note that the outer conductor 3a of the coaxial line 3 is connected to the opening 2a, and the inner conductor 3b of the coaxial line 3 is connected to the top of the matching body 5.

In this way, the conical matching body 5 can prevent power reflection at the connection between the coaxial line 3 and the waveguide space S (lower waveguide space ff5s,), and furthermore, the coaxial line 3
Since the direction of the electric field can be accurately converted by 90° between the waveguide space S1 and the waveguide space S1, as shown by arrows A and B in FIG.
It can be taken out inside.

FIG. 3 shows the reflection coefficient characteristics seen from the opening 2a (connector part). From this figure, it can be seen that there is less reflection (and therefore, power can be fed more effectively).

By the way, the cross-sectional shape of the corner part C+-C3 of the waveguide space S including the feeding power detour gap, ~D, is as follows.
Since both are formed as a regular octagonal half-section, it is possible to sufficiently prevent the reflection of the supplied power at this corner part C7 to C5, and to effectively perform power supply through this corner part 01 to C5. Can be done.

Figure 4 shows the internal field characteristics (solid line) in the lower waveguide space S, and the internal field characteristics (broken line) in the upper waveguide space S2. ,, It can be seen that the internal fields at S2 are almost equal, but this is because some corners are 0.
This means that there is no reflection at 1 to C1.

In addition, the intermediate metal plate 6a and the intermediate metal plates f3b and 6c are provided at a position W11 such that the impedance Z + -Z 21 Z s is equal, for example, at a position that divides the metal plate 1.2 into three equal parts. Therefore, both waveguide spaces S
l? In-begence matching between S z and S i can be achieved, and more effective power feeding becomes possible.

Therefore, the power efficiently supplied to the lower waveguide space S as described above passes through the lower waveguide space S1, as shown by the arrow Pf, to the circumference 5!4 and the intermediate metal plate 6a.
It efficiently bypasses the gap D1, that is, the corner part C, and reaches the intermediate waveguide space S.
It propagates while branching towards the central part and the outer periphery of 3.

Then, when the feeding power reaches the upper waveguide space S2 from the intermediate waveguide space S, and passes through the lower waveguide space S2, the power is radiated through the slot 1a formed in the metal disc 1. Ru. The power density characteristics at this time are as follows: Pt5
The characteristic is as shown by the symbol M in the S diagram. This characteristic M becomes approximately sawtooth, which means that when power is radiated through slot 1 &'%'Ilkl-'R-h'a,
m JL-τu#Y Th,,w4! W l+
Since the +y+LM power is supplied, the overall level of this characteristic M becomes approximately the same smoothly regardless of the distance R from the termination.

That is, according to the circular waveguide of this embodiment, I
After the feeding power is effectively taken into the IS, the feeding power is efficiently passed through the corners C8 to C1, and when it is radiated, the radiated power is almost uniform, so the antenna gain is greatly increased. It will improve.

In addition, if the cross-sectional shape of the corner portions C, -C, including the gap is formed into a semicircular shape, this corner portion C3~
Although reflection of the supplied power at C2 can be sufficiently prevented, a gentle curve close to a semicircle will cause less reflection.

As shown in FIG. 6, the annular terminating resistor 7' is not provided, and the feed power bypass gap is placed in the intermediate metal plate 6b at a position λ/4 on the outer circumferential side from the feed power bypass gap D3. In this case, as shown in Figure t57, the feeding power P is divided into the feeding power P and the feeding power P2 below the feeding power bypass gap, and the feeding power P1 is divided into the feeding power P and the feeding power P2. Above the feed power bypass gap, the feed power is divided into left feed power P, L and right feed power Put, and feed power P2 is divided above the feed power bypass gap,
It is divided into left side feeding power P2L and right side feeding power PAH.

Therefore, the feed power PL directed to the left in the upper waveguide space Sz becomes (PIL+P2L), and the feed power P1L and the feed power P2. Since both phases are zero, they do not cancel each other out.

In addition, the power supply PR going to the right in the upper waveguide opening S2
becomes Habo(PIR1P2R), and this power supply p
The phase between ++'t and the feed power P2R (or the phase between the internal fields) is λ/2, and the intensity is approximately P/4, so they cancel each other out and the feed power PR is zero or small. value.

Note that although a portion of the feeding power Put and the feeding power Ple enters into the intermediate air conduction darkness S3, the magnitude thereof is small.

In addition, in a modification of this embodiment, the waveguide space S 1-
Waveguide space S of S 2a+ S zb-S s
ga+S i [Refer to FIG. 10 (A) 1 impedance Z 211t Z 3 or waveguide space s 2b,
s, open impedance z 2b.

Z are not equal, that is, Z 2a;' Z 3 or 6
or z2b≠Z, the intermediate metal plate 6
The impedance is ZM at the outer peripheral edge and inner peripheral edge of b.
(This ZM is ZM” = Z 2az s= Z zb
174 matching portions 8a having a length l equal to the line wavelength λ are formed.

In addition, the matching part between the waveguide spaces s2b, s is almost the same as the matching part 8a between the waveguide spaces SzlLtSs (the same goes for matching R8b to 8f, 9a, 9b, and 10, which will be described later). configured. As a result, the waveguide space S2 (11S
Impedance matching can be achieved between z and between the waveguide spaces s2b, s, and effective power feeding can be performed.

In addition, in order to achieve impedance matching between both waveguide openings S2a and Sj and impedance matching between both waveguide spaces 52)) and 33, the intermediate metal plate 6b is coated with a metal plate shown in FIG.
Matching portions 81) to 8d having shapes as shown in b) to (d) may be formed.

Z6 is determined to satisfy ZM''=ZzaZs, and length! is set to 174 of the line wavelength λ.

Furthermore, as shown in fIS10 figure (e), the metal disk 2
A portion 9a whose length l is 1/4 of the line wavelength λ from to the circumferential wall 4'' having a semicircular cross section is formed in a step shape so that it becomes narrower toward the corner portion 02', and this portion 9a is used as a matching portion. In this case, the impedance of this matching section 9a is also ZH satisfying Z M2 = Z za Z y as in the above-mentioned one.
is set to

Further, as shown in FIG. 10(f), the values of the gap D2 and the dimension G of the corner part C2 where the length l is 1/4 of the line wavelength λ are set to 1151! Then, the impedance of this corner portion C2 may be set to ZM that satisfies Z M'' = Z 2a Z s.

For example, in the case of the one shown in @io diagram (a), the impedance of the upper waveguide space S2a includes the corner ff1sc2.

Moreover, in FIG. 10(,)-(f), Z 2 a < 2
3, but in the case of Figure 10 (g) and (h), 22 a > Z s In the case of Figure 10 (g),
The impedance is ZM at the outer peripheral edge of the intermediate metal plate 613.
(This ZM satisfies 2M2=Z2aZ) and has length l
174 matching portions 8e with line wavelength λ are formed,
Thereby, impedance matching between the waveguide spaces S fat S 3 is achieved.

In addition, in the case of Fig. 10 (h), the circumference of the metal disk 2 is circular in cross section! ! ! The length l leading to 4" is 1 of the line wavelength λ
/4 part 9b is formed in a step shape so as to become wider toward the corner part C2', and the impedance of this part 9b is also 2M.
ZM that satisfies 2=Z2aZ is selected.

In the case of the one shown in FIG. 10 (11), the impedance of the upper waveguide space S2a includes the corner portion C2'.

Moreover, impedance matching may be performed by providing an annular matching body 10 as shown by a chain line in the fpJ2 diagram also between the waveguide spaces S, , S3.

Note that angles α and θ in the figure are both approximately 45°.

In addition, as shown in FIGS. 8 and 9, in the series coaxial circular waveguide line as an fjS2 embodiment of the present invention, rjS1
The intermediate metal plate 6a in the embodiment is not provided, that is, the intermediate waveguide space S is not formed, and the circular intermediate metal plate 6c has a one-stage structure and the annular intermediate metal plate is formed on the outer periphery of the circular intermediate metal plate 6c. Further, on the outer circumferential side of the lower waveguide space S1, an annular lower waveguide space S,a is formed in the shape of r&, which places the branch waveguide at vI. A circular lower waveguide space Slb is formed on the circumferential side.

Further, the other configurations are almost the same as the first embodiment, and the eighth embodiment.
In FIG. 9, the same reference numerals as in FIGS.

Note that the branch waveguides may be configured in multiple stages by appropriately combining each of the above-mentioned embodiments.

Further, the cross-sectional shape of a part of the corner may be formed by changing the number of angles so that it is different from a regular octagon.

Note that the shape of the matching body 5 may not be a conical shape, but may be set to a shape in which the contour line of the vertical plane shape changes in an exponential function or the like. At this time, the outer conductor 3 of the coaxial line 3
The connecting end of a to the opening 2a may also have a shape that changes in an exponential function or the like.

Further, the matching body 5 may be hollow or solid, and the matching body 5 does not need to be entirely made of metal as long as it has a metal layer on at least the surface.

Furthermore, the present invention can be applied in the same manner even if the power feeding section is a waveguide instead of the coaxial line 3 as in each of the above-described embodiments.

〔Effect of the invention〕

As detailed above, according to the waveguide of the present invention, the waveguide is arranged with a gap for feeding power detour left between the waveguide space surrounded by the metal wall and the peripheral wall within the waveguide space. The intermediate plate formed in
The intermediate plate is disposed within the waveguide space so that the impedance between the waveguide spaces partitioned by the intermediate plate is equal, and a branch waveguide is provided within the waveguide space. is provided, so that effective power supply is possible.

Further, according to the waveguide of the present invention, the waveguide space surrounded by the metal wall and the intermediate plate disposed within the waveguide space with a gap for detouring the feeding power left between the peripheral wall and the waveguide space. , a power feeding section connected to a power feeding opening formed in the waveguide space, and a connection section between the waveguide space sections in order to achieve impedance matching between the waveguide space sections partitioned by the intermediate plate. A waveguide space partitioned by the intermediate plate has a simple configuration in which a matching body having a desired impedance is provided near (including the connection part) and a branch waveguide is provided within the waveguide space. This has the advantage of being able to achieve impedance matching between the antennas, improving power feeding efficiency, and making it possible to increase the size of the antenna.

[Brief explanation of drawings]

Figures fjS1 to 7 show a parallel (Christmas tree) type coaxial circular waveguide line when applied to a large antenna as the first embodiment of the present invention, and Figure 3 shows its reflection coefficient characteristics. Figure 4 shows the inside of the graph.
Figure 5 is a graph showing the Il characteristics, Figure 5 is a graph showing the power density characteristics along the radial direction of the upper space, Figures 6 and 7 are variations thereof, and Figure 6 is a cross section of the main part. 7 are cross-sectional views showing the propagation state of the feeding power, and FIG. 8.9 shows a series coaxial circular waveguide line when applied to a large antenna as a second embodiment of the present invention. Fig. 8 is a central longitudinal sectional perspective view thereof, Fig. 9 is a central vertical sectional view thereof, and fjS10 Figs. 12 shows a conventional circular waveguide, FIG. 11 is a perspective view of the center longitudinal section thereof, and FIG. 12 is a longitudinal sectional view thereof. 1...Metal disk, 1a...Slot, 2...Metal disk,
2a...Power supply opening, 3...Coaxial line, 31L...Outer conductor, 3b...Inner conductor, 4.4', 4"...Peripheral wall, 5
．． 5'--alignment body, 6a, 6b, 6e...intermediate metal plate,
7.7'--1 one end resistor, 8 a-8f-9a, 9b
, l O・- matching part (1!1 combination), C+ + C21
C2' 1C1...Part of corner, D I-D 2 tD
s - D 4...Gap for feeding power detour, S...Waveguide space, Sl...Upper waveguide space, S, a...Annular lower waveguide space (branch waveguide), S, b... Circular lower waveguide space, S2... upper waveguide space (branch waveguide), Sea... annular upper waveguide space (branch waveguide), S2b... circular upper waveguide space (branch waveguide), S3...Intermediate waveguide (branch waveguide).

Claims (2)

[Claims] (1) A waveguide space surrounded by a metal wall, an intermediate plate disposed within the waveguide space with a gap for detouring the power supply between the surrounding wall thereof, and an intermediate plate formed in the waveguide space. The intermediate plate is disposed within the waveguide space so that the impedance between the waveguide spaces partitioned by the intermediate plate is equal, and characterized in that a branch waveguide is provided within the
waveguide line. (2) A waveguide space surrounded by a metal wall, an intermediate plate disposed within the waveguide space with a gap for detouring the power supply between the surrounding wall thereof, and an intermediate plate formed in the waveguide space. In order to achieve impedance matching between the waveguide spaces partitioned by the intermediate plate,
A waveguide line, characterized in that a matching body having a desired impedance is provided near a connection between the waveguide spaces, and a branch waveguide is provided within the waveguide space.