JPH0770890B2 - Interdigitated coupler - Google Patents

Description

TECHNICAL FIELD The present invention relates to an interdigitated coupler formed by a microwave integrated circuit.

[Conventional technology]

FIG. 2 is a diagram showing a conventional interdigitated coupler shown in P34 of Microwave 1976 MAY, for example, (a) is a pattern diagram and (b) is a cross-sectional diagram. Is a conductor pattern, (2) is a wire that is a coupling means for electrically coupling the conductor patterns, (3)
Is a dielectric, (4) is a ground conductor, E, F, G, H, are terminals,
E ', F', G ', H', and Q'indicate points, and X indicates a central axis.

Next, the operation will be described. The electric wave coming in from terminal E is divided into two parts G and H, and the electric wave coming out to H is delayed by 90 ° in phase from the electric wave coming out to G. No radio wave comes out to the terminal F. Next, considering the case where radio waves of the same power enter from terminals G and H, the incident wave to H is more in phase than the incident wave to G.
If you have proceeded 90 °, radio waves will come out only at terminal E, and at terminal F
There is no radio wave coming out. On the contrary, if the incident wave on G leads the incident wave on H by 90 ° in phase, the radio wave will come out only to the terminal F and not to the terminal E. The same relationship holds for the other terminals. These characteristics are performances obtained when the circuit is symmetric and the line length between terminals is also the same. However, in this case, the route HH'QE'E from the terminal H to the terminal E is asymmetric with respect to the central axis X.
Considering that the line length is the route G from terminal G to terminal F
Compared with the line length of F'F or GG'F, it is half as long as E'H '. Regarding the high-frequency characteristics, the reactance is slightly increased between E'H 'and the terminals E to G, H.
The degree of coupling to is slightly deviated from 3 dB.

[Problems to be solved by the invention]

Since the conventional interdigitated coupler is configured as described above, the symmetry of the conductor pattern is poor, and the line length between each terminal is also different, so the coupling characteristics and phase characteristics are not good. There was a problem.

The present invention has been made to solve the above problems, and improves the symmetry of the conductor pattern, makes the line length between the terminals the same, and has good coupling and phase characteristics. The purpose is to obtain an ited coupler.

[Means for solving problems]

An interdigitated coupler according to the present invention is connected to and connected to a first terminal, and the first and third terminals and the second and fourth terminals are connected in the direction of the second and fourth terminals. Of the first and second branch pieces extending in the vicinity of the central portion of the first parallel conductor piece and the second branch piece parallel to each other and connected to the fourth terminal by connecting to the fourth terminal. A second conductor pattern that extends in the direction of the terminal to the vicinity of the center and is continuous at the center with a second conductor pattern including a third branch and a fourth branch parallel to the first and second branches. And a second bifurcating piece sandwiching the second bifurcating piece and extending to the vicinity of the first terminal, and a sixth bifurcating section including a sixth bifurcating piece continuously connected to the third terminal. , And the third branch piece which is continuously sandwiched at the central portion and extends to the vicinity of the fourth terminal. Has a second bifurcated portion composed of a bifurcated piece and an eighth bifurcated piece that is continuously connected to the second terminal, and these first and second bifurcated portions are continuous in the central portion. And the connected third conductor pattern, the tip of the first branch piece and the tip of the third branch piece, the tip of the second branch piece and the tip of the fourth branch piece, the No. 5, the tip of the branch piece and the third terminal, and bridging means for bridging the tip of the seventh branch piece and the second terminal, respectively.

Further, the bridging means is a wire or a gold ribbon.

[Action]

The interdigitated coupler according to the present invention has good pattern symmetry, and the line lengths between the terminals are almost equal, so that the coupling degree of 3 dB and the phase characteristic of 90 ° difference are designed values over a wide band. Get closer to.

Example of Invention

An embodiment of the present invention will be described below with reference to the drawings. First
FIG. 1 is a pattern diagram showing an interdigitated coupler according to an embodiment of the present invention. In FIG.
(1) is a conductor pattern, (2) is a wire that is a bridging means for bridging the conductor patterns, A is a first terminal, B is a second terminal, C is a third terminal, and D is a fourth. , And X indicates the central axis. (5) is a first conductor pattern which is connected to the first terminal A and comprises a first branch piece (5a) and a second branch piece (5b) which are parallel to each other, and (6) is a fourth terminal ( A second conductor pattern (7) including a third branch piece (6a) and a fourth branch piece (6b), which are connected to D) and are parallel to the first and second branch pieces (5a) (5b). ) Is a first bifurcated portion composed of a sixth branch piece (7b) and a fifth branch piece (7a) connected to the third terminal (C), and (8) is a second terminal (B) A second bifurcated portion composed of an eighth branch piece (8a) and a seventh branch piece (8b) connected to each other, and (9) has the first and second bifurcated parts (7) and (8). It is the 3rd conductor pattern connected continuously. The conductor pattern in the present invention is as follows:
The tips of the pair of terminals on the diagonal line are separated into comb-shaped lids, and the remaining pair of terminals are connected by a conductor pattern so as to squeeze between them, and the width of the conductor pattern portion is four. It consists of a railroad track and three spaces. As with the conventional side, the radio waves entering terminal A are equally distributed to terminals C and D,
The terminals are 90 ° out of phase with each other, and no electric wave comes out to the terminal B. The other terminals are the same as in the conventional example.

By the way, the pattern according to the present invention is 180 ° rotationally symmetric with respect to the center of the pattern, and at the same time, is substantially left-right symmetric with respect to the central axis X except for the central portion. The line length from D to terminal A is almost the same. By doing so, the coupling degree becomes close to 3 dB, and the phase difference of 90 ° becomes close to the design value.

Although the wire is shown as the coupling means in the above embodiment, a gold ribbon or the like may be used.

(Effects of the Invention) As described above, according to the present invention, the first and third terminals and the second and fourth terminals are connected to the first terminal in the direction of the second and fourth terminals. Of the first branch and second branch extending parallel to each other and connected to the fourth terminal in the direction of the first and third terminals. A second conductor pattern that extends to the vicinity of the central portion and is composed of a third branch piece and a fourth branch piece that are parallel to the first and second branch pieces and a second conductor pattern that is continuous in the central portion
The fifth bifurcating piece sandwiching the bifurcating piece and the first bifurcated portion formed of the sixth bifurcating piece connected to the third terminal, and the seventh bifurcating piece sandwiching the third bifurcating piece continuously in the central portion. Branch piece and the above second
Third conductor pattern having a second bifurcated portion composed of an eighth branch piece connected to the terminal of the above, and these first and second bifurcated portions being continuously connected at the central portion. And a tip of the first branch piece and a tip of the third branch piece, a tip of the second branch piece and a tip of the fourth branch piece, a tip of the fifth branch piece and the third terminal, and The tip of the seventh branch piece and the second piece
Since there is provided bridging means for bridging each of the terminals, there is an effect that a good coupling degree and phase characteristic can be obtained.

[Brief description of drawings]

FIG. 1 is a pattern diagram showing an interdigitated coupler according to an embodiment of the present invention, FIG. 2 is a diagram showing a conventional interdigitated coupler, and FIG. 2 (a) is a pattern diagram, FIG. 2 (b) is a sectional view. In the figure, (1) is a conductor pattern, (2) is a wire,
(3) is a dielectric, (4) is ground, (5) is a first conductor pattern, (5a) is a first branch piece, (5b) is a second branch piece, and (6) is a second branch piece. A conductor pattern, (6a) a third branch piece, (6b) a fourth branch piece, (7) a first bifurcated portion,
(7a) is a fifth branch piece, (7b) is a sixth branch piece, (8)
Shows a second bifurcated portion, (8a) shows an eighth branch piece, (8b) shows a seventh branch piece, and (9) shows a third conductor pattern. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (3)

[Claims] 1. A first device provided on a dielectric and adjacent to each other.
Terminal (A) and third terminal (C), and a second terminal (B) and a fourth terminal which are arranged to face the first and third terminals (A) and (C) and which are adjacent to each other. Terminal (D) of each of these terminals and the terminals (D) of
Terminals (A) and (C) and the second and fourth terminals (B)
In a microwave circuit interdigitated coupler having a plurality of conductor patterns arranged between (D) and the conductor patterns, the first terminal (A) is connected. And then connected, the second and fourth
Of the first and third terminals (A) and (C) and the second and fourth terminals (B) and (D) in the direction of the terminals (B) and (D) of FIG. A first conductor pattern (5) consisting of a parallel first branch piece (5a) and a second parallel branch piece (5b) is connected to and connected to the fourth terminal (D), The first and second branch pieces (5) extending in the direction of the third terminals (A) and (C) to the vicinity of the central portion.
a) A second conductor pattern (6) consisting of a third branch piece (6a) and a fourth branch piece (6b) parallel to (5b) and the second branch piece continuously at the central portion A fifth branch piece (7a) sandwiching (5b) and extending to the vicinity of the first terminal (A) and a sixth branch piece (7b) continuously connected to the third terminal (C). A first bifurcated part (7) and a third branch piece (6a) sandwiching the third branch piece (6a) continuously in the central part and extending to the vicinity of the fourth terminal (D) ( 8b) and a second bifurcating part (8) consisting of an eighth branch piece (8a) continuously connected to the second terminal (B), and these first and second bifurcating parts (8) are provided. A third conductor pattern (9) in which the parts (7) and (8) are continuously connected at the central part, the tip of the first branch piece (5a) and the third branch piece (6a).
Tip, the tip of the second branch piece (5b) and the tip of the fourth branch piece (6b), the tip of the fifth branch piece (7a) and the third terminal (C), and An interdigitated coupler characterized by comprising bridging means for bridging the tip of the seventh branch piece (8b) and the second terminal (B). 2. The interdigitated coupler according to claim 1, wherein the bridging means is a wire. 3. The interdigitated coupler according to claim 1, wherein the bridging means is a gold ribbon.