JPH11168308A - Coaxial power combiner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small-sized coaxial power combiner with excellent wide band characteristics in an LIHF frequency range. SOLUTION: This combiner is provided with a combiner line 1, three input lines 2, 3 and 4 connected to the combiner line 1, three lines 5, 6 and 7 for impedance conversion successively and coaxially connected to the combiner line 1 and an output terminal 8 connected to the projected end part of the line 7 for the impedance conversion. The input lines 2, 3 and 4 are arranged so as to be perpendicular to the combiner line 1 and be perpendicular and point symmetrical with each other centering the line 1. The lines 5, 6 and 7 for the impedance conversion are formed integrally with the line 1. The lines 5, 6 and 7 for the impedance conversion are the equal length and the line length is (1/4)λ.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention mainly relates to LIH
More particularly, the present invention relates to a coaxial power combiner suitable for obtaining broadband characteristics and in-phase characteristics between input terminals.

[0002]

2. Description of the Related Art As a conventional coaxial power combiner, there is known a coaxial type power combiner described in JP-A-1-103003. In this conventional coaxial power combiner, the central conductors of a plurality of coaxial lines are connected to the central conductor of one coaxial line at right angles and symmetrically from the surroundings, and matching (1/1 /
4) The transformer of λ (where λ is the propagation wavelength of the input signal) is provided. That is, as shown in FIGS. 6 and 7, this conventional coaxial power combiner includes a coaxial connector 61 forming an input / output terminal of a signal, a central conductor 62 of six coaxial lines for synthesizing a signal, A dielectric ring 63 supporting the conductor 62 and a center conductor 6 to which an output signal is applied;
4 and blocks 65 and 66 forming an outer coaxial conductor. The center conductors 62 of the six coaxial lines are connected to the center conductor 64 at right angles and symmetrically.

In a conventional coaxial power combiner, each input signal is applied to a central conductor 62 of six coaxial lines, and is six times as large as an input signal from a coaxial connector 61 via a central conductor 64 provided at the center. Is output. The characteristic impedance Z1 of the (1/4) λ transformer provided on the central coaxial line and the characteristic impedance Z2 of the (1/4) λ transformer provided on a plurality of coaxial lines to be combined are input / output terminals. If the characteristic impedance of
× Z1 = Z2.

[0004]

However, in the conventional coaxial power combiner, (1) of the LIHF frequency band is used.
/ 4) Since the transformer of [lambda] is large, there is a problem that the device becomes large and cannot be installed in a miniaturized television broadcaster.

Further, in the conventional coaxial type power combiner, it is difficult to cover a wide band such as the LIHF frequency band, so that several types of devices are required to cover the entire LIHF frequency band. There's a problem.

It is an object of the present invention to provide a small coaxial power combiner that can be installed in a television broadcast in the LIHF frequency band.

Another object of the present invention is to provide a wideband coaxial power combiner that can cover all of the LIHF frequency band with one device.

[0008]

In order to solve the above-mentioned problems, a first aspect of the present invention is a combination line, three input lines connected to the combination line, and the combination line. Three impedance conversion lines sequentially coaxially connected to the transmission line, and an output terminal connected to a protruding end of the impedance conversion line located farthest from the synthesis line, The input lines are arranged at right angles to the combining line and mutually perpendicular and point-symmetric with respect to the combining line. When the propagation wavelength of the input signal is λ, the impedance conversion is performed. The length of each of the service lines is (1/4) λ.

In a second aspect of the present invention, one combining line, four or more input lines connected to the combining line, and a coaxial connection to the combining line are sequentially provided. Three impedance conversion lines, and an output terminal connected to a protruding end of the impedance conversion line farthest from the synthesis line, wherein the input line is perpendicular to the synthesis line. Are arranged so as to be mutually symmetrical with respect to the synthesis line,
When the propagation wavelength of the input signal is λ, the line length of each of the impedance conversion lines is (１ ／) λ.

According to a third aspect of the present invention, one combining line, four or more input lines connected to the combining line, and a coaxial connection to the combining line are sequentially provided. Two impedance conversion lines, and an output terminal connected to a protruding end of the impedance conversion line farthest from the synthesis line, wherein the input line is perpendicular to the synthesis line. Are arranged so as to be mutually symmetrical with respect to the synthesis line,
When the propagation wavelength of the input signal is λ, the line length of each of the impedance conversion lines is (１ ／) λ.

[0011]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a longitudinal sectional view showing a coaxial power combiner as a first embodiment of the present invention.
FIG. 2 is a sectional view showing the coaxial power combiner of FIG. 1 cut along the line AA. As shown in FIGS. 1 and 2,
The coaxial power combiner of the present invention includes one combining line 1,
Three input lines 2 connected to the synthesis line 1,
3, 4, three impedance conversion lines 5, 6, 7, which are sequentially and coaxially connected to the synthesis line 1, and the impedance conversion line 7 located farthest from the synthesis line 1. Output terminal 8 connected to the tip
And

The input lines 2, 3, 4 are arranged at right angles to the combining line 1 and at right angles to each other with respect to the combining line 1 and in point symmetry. The input lines 2, 3, 4 are fixed to the combining line 1 by screws 9, for example. The impedance conversion lines 5, 6, and 7 are formed integrally with the synthesis line 1. The impedance conversion lines 5, 6, and 7 are of equal length, and their line length is (1/4) λ. Therefore, the impedance conversion lines 5, 6, 7 are
As shown in FIG. 3, it has a role as a three-stage impedance converter of a Chebyshev (1/4) λ transformer.

The combining line 1 and the input lines 2, 3, 4
And the impedance conversion lines 5, 6, 7 and the output terminal 8 are inner conductors. Outer conductors 10 are arranged outside these inner conductors at predetermined intervals. The inner conductor and the outer conductor 10 are insulated by a plurality of insulating support members 11 made of Teflon. Further, the outer conductor 9 is supported by the insulating support member 11 such that the central axis is the same as the central axis of the inner conductor. The high frequency power applied to one end of the input lines 2, 3, 4 is
3 and 4 are propagated and input to the combining line 1. The high-frequency powers input from the three directions are combined in the combining line 1 and propagate through the impedance converting lines 5, 6, and 7, and the output terminal 8
Output. At this time, the input high-frequency power needs to have the same phase and the same amplitude.

Next, a specific embodiment will be described. In this coaxial power combiner, the input power is several KW and the combined output power is ten and several KW.
AX-39D (product name), and the output terminal 8 is NA
X-77D (trade name). The input lines 2, 3, 4 and the output terminal 8 each have a characteristic impedance of 50Ω. Input lines 2, 3, 4 are 1
It has an outer diameter of 6.9 mm. The output terminal 8 is connected to the 33.
It has an outer diameter of 4 mm. The synthesis line 1 is 16.7
It has a characteristic impedance of Ω and an outer diameter of 58.2 mm.

The impedance conversion line 5 is 19.7
It has a characteristic impedance of Ω and an outer diameter of 55.4 mm. The impedance conversion line 6 has a characteristic impedance of 29Ω and an outer diameter of 47.5 mm. The impedance conversion line 7 has a characteristic impedance of 42.5Ω and an outer diameter of 37.9 mm.

Next, a second embodiment of the present invention will be described with reference to the drawings. FIG. 4 is a schematic diagram showing a coaxial power combiner according to a second embodiment of the present invention. The coaxial power combiner includes one combining line 30 and four or more input lines 21 to 21 connected to the combining line 30.
21n (n is an integer of 4 or more), three impedance conversion lines 31, 32, and 33 sequentially and coaxially connected to the synthesis line 30, and the synthesis line 30
And an output terminal connected to the protruding end of the impedance conversion line 33 which is furthest from the line. The input lines 21 to 21n are arranged at right angles to the combining line 30 so as to be line-symmetric with respect to the combining line 30. The line length of each of the impedance conversion lines 31, 32, and 33 is (1/4) λ
It is. The coaxial power combiner according to the second embodiment of the present invention is the same as the first embodiment of the present invention except that it has four or more input lines 21 to 21n. In the coaxial power combiner of FIG.
Has a characteristic impedance of 50 / nΩ, the impedance is converted to Z0 (= 50Ω) by the output terminal, thereby providing a coaxial power n combiner.

Next, a third embodiment of the present invention will be described with reference to the drawings. FIG. 5 is a schematic diagram showing a coaxial power combiner as a third embodiment of the present invention. The coaxial power combiner includes one combining line 50 and four or more input lines 41 connected to the combining line 50.
To 41n (n is an integer of 4 or more), two impedance conversion lines 51 and 52 which are sequentially and coaxially connected to the synthesizing line 50, and are located farthest from the synthesizing line 50. The impedance conversion line 52
And an output terminal connected to the protruding end portion. The input lines 41 to 41 n are arranged so as to be perpendicular to the combining line 50 and to be line-symmetric with respect to the combining line 50. The line length of each of the impedance conversion lines 51 and 52 is (1/4) λ. The coaxial power combiner according to the third embodiment of the present invention
The configuration is the same as that of the first embodiment of the present invention except that the input lines 41 to 41n and the two impedance conversion lines 51 and 52 are provided. This coaxial power combiner is effective when the band is narrow in the VHF frequency band and (1/4) λ is further increased.

[0018]

The coaxial power combiner of the present invention does not require a transformer having an input line of (1/4) λ, so that the size of the input line can be minimized, so that the size can be reduced. .

In the coaxial power combiner of the present invention, the impedance conversion between the output terminals is performed by (1/1) after the signals are combined.
4) Since the λ transformer has a two-stage or three-stage configuration, it has a wide band characteristic, so that all of the LIHF frequency band
Can be covered by one device.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a coaxial power combiner as a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing the coaxial power combiner of FIG. 1 cut along line AA.

FIG. 3 is a schematic diagram illustrating the coaxial power combiner of FIG. 1;

FIG. 4 is a schematic diagram illustrating a coaxial power combiner according to a second embodiment of the present invention.

FIG. 5 is a schematic diagram illustrating a coaxial power combiner according to a third embodiment of the present invention.

FIG. 6 is a cross-sectional view showing a conventional coaxial power combiner.

FIG. 7 is another sectional view showing a conventional coaxial power combiner.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Synthesis line 2, 3, 4 Input line 5, 6, 7 Impedance conversion line 8 Output terminal 9 Screw 10 Outer conductor 11 Insulated support member 21-2n Input line 30 Synthesis line 31, 32, 33 Impedance conversion line 41-4n Input line 50 Synthesis line 51, 52 Impedance conversion line

Claims (6)

[Claims] 1. A synthesis line, three input lines connected to the synthesis line, three impedance conversion lines sequentially connected coaxially to the synthesis line, and An output terminal connected to the tip of the impedance conversion line that is farthest from the transmission line, and the input line is at a right angle to the synthesis line and mutually connects the synthesis line. It is arranged so as to be perpendicular to the center and symmetrical with respect to the point, and when the propagation wavelength of the input signal is λ, the line length of each of the impedance conversion lines is (１ ／) λ. Coaxial power combiner. 2. The coaxial power combiner according to claim 1, wherein the insulating member for insulating the combining line, the impedance converting line, and the input line from the outer conductor is made of Teflon. Characteristic coaxial power combiner. 3. A synthesis line, four or more input lines connected to the synthesis line, and three impedance conversion lines sequentially and coaxially connected to the synthesis line. An output terminal connected to a tip end of the impedance conversion line farthest from the synthesis line, wherein the input line is perpendicular to the synthesis line and Are arranged so as to be line-symmetric with respect to the transmission line, and when the propagation wavelength of the input signal is λ, the line length of each of the impedance conversion lines is (１ ／) λ. Coaxial power combiner. 4. The coaxial power combiner according to claim 3, wherein the insulating member that insulates the combining line, the impedance converting line, and the input line from the outer conductor is made of Teflon. Characteristic coaxial power combiner. 5. A synthesis line, four or more input lines connected to the synthesis line, and two impedance conversion lines sequentially and coaxially connected to the synthesis line. An output terminal connected to a tip end of the impedance conversion line farthest from the synthesis line, wherein the input line is perpendicular to the synthesis line and Are arranged so as to be line-symmetric with respect to the transmission line, and when the propagation wavelength of the input signal is λ, the line length of each of the impedance conversion lines is (１ ／) λ. Coaxial power combiner. 6. The coaxial power combiner according to claim 5, wherein the insulating member for insulating the combining line, the impedance converting line, and the input line from the outer conductor is made of Teflon. Characteristic coaxial power combiner.