JP2002290105A - Variable dielectric phase shifter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a variable dielectric phase shifter, realizing a simple/low loss dielectric phase shifter which simultaneously gives appropriate phase differences to a plurality of power feeders of a phased array antenna and in which the works of the attachment/removal and exchange of parts are omitted in the operation of phase control. SOLUTION: The variable dielectric phase shifter has microstrip lines 211 to 214 formed on a dielectric substrate 1 and a dielectric board 301, which covers a part of the upper faces of the microstrip lines 211 to 214 and is arranged so that it can freely move on the substrate 1; and in the microstrip lines 211 to 214, line characteristics are made to continuously (or stepwise) change in the transmitting direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a high-frequency variable phase shifter, and more particularly to a simple variable dielectric phase shifter using a dielectric for a phased array antenna formed on a planar circuit.

[0002]

2. Description of the Related Art There are two types of phase shifters used in a planar circuit: a phase shifter having a fixed shift amount and a variable phase shifter capable of controlling the shift amount. A phase shifter with a fixed shift amount has a redundant portion on a line printed on a plane circuit that provides a desired delay, and can provide a transmission delay according to the line length of the redundant portion.

On the other hand, there are many variable phase shifters, and a first example is a PIN diode phase shifter. It is small in weight and size and inexpensive. As a second example, there is a method in which a voltage-controllable dielectric is used for a transmission line as a circuit-constituting substrate (Japanese Patent Laid-Open No. 77303), and similar effects can be obtained by using liquid crystal for the dielectric substrate. Report (Kuki, Fujikake, Aida, Nomoto, "Microwave Variable Delay Line Using Liquid Crystal", 1999 IEICE Society Conference, C-2-6
3, p92. See also). As a third example,
"Honma, Maruyama, Hori," Proposal of Directional Offset Type Antenna Using Dielectric Phase Shifter "," IEICE General Conference, 2000, B-1-141, pp. There are 141. This is a variable-type phase shifter with a dielectric on multiple lines.A dielectric that gives a phase difference to the lines by mounting a triangular dielectric plate on parallel lines formed on a dielectric substrate A phase shifter has been realized.

[0004]

In a phase shifter having a fixed shift amount in which a phase difference is previously incorporated in a plane circuit, it is necessary to newly construct a circuit in order to change the phase.
The PIN diode phase shifter mentioned as the first example of the variable phase shifter capable of controlling the shift amount has a large insertion loss, so that an amplifier needs to be added, and the circuit becomes complicated.
In the method of using a voltage-controllable dielectric as a circuit board as the second example of the variable phase shifter, it is necessary to configure the transmission line on a special voltage-controllable board, which complicates the structure. . In the variable type phase shifter mentioned as the third example,
In order to adjust the phase, it is necessary to mainly attach and detach or replace the dielectric, and for adjustment, it is necessary to prepare dielectrics of many shapes in advance.

The present invention has been made in view of the above circumstances, and provides an appropriate phase difference to a plurality of feeder lines of a phased array antenna at the same time, so that the operation of attaching / detaching or replacing components in the operation of phase control is omitted. -It is an object to provide a variable dielectric phase shifter that realizes a low-loss dielectric phase shifter.

[0006]

In order to achieve the above object, a variable dielectric phase shifter according to the present invention comprises a microstrip line formed on a dielectric substrate and a part of the upper surface of the microstrip line. And a variable dielectric phase shifter having a dielectric disposed so as to be freely movable on the substrate, wherein the microstrip line has a line characteristic that changes continuously or stepwise in the transmission direction. It is a strip line.

That is, by sliding the dielectric in the transmission direction of the microstrip line, the line characteristics vary depending on the position of the dielectric. Change the effective length. This makes it possible to control the amount of phase shift by moving the dielectric. As a result, a simple variable dielectric phase shifter is realized.

The present invention also relates to the variable dielectric phase shifter, wherein the microstrip line is a microstrip line having a line width continuously or stepwise changed in a transmission direction. It is a feature.

That is, by sliding the dielectric in the transmission direction of the microstrip line, the effective length of the microstrip line is changed utilizing the fact that the influence of the dielectric varies depending on the position. This makes it possible to control the amount of phase shift by moving the dielectric. As a result, a simple variable dielectric phase shifter is realized.

The present invention is also the variable dielectric phase shifter, wherein the microstrip line is a microstrip line composed of two or more parallel lines.

That is, by sliding the dielectric in the transmission direction of the line, the effective length of the microstrip line is changed by utilizing the fact that the influence of the dielectric varies depending on the position. Since different characteristics are prepared for each microstrip line, the effective length can be varied for each microstrip line. This makes it possible to control the phase difference between the microstrip lines by moving the dielectric. As a result, a simple variable dielectric phase shifter that can control the phases of a plurality of microstrip lines with the same structure is realized.

The present invention also relates to the variable dielectric phase shifter, wherein the microstrip line is two or more transmission lines, and the distance between the centers of two adjacent lines is different from the transmission direction. It is a microstrip line that changes smoothly.

That is, by sliding the dielectric, the effective length of the microstrip line is changed by utilizing the fact that the intersection length with the dielectric changes depending on the position of the dielectric. Since a different shape is prepared for each microstrip line, the effective length can be varied for each microstrip line. Thereby,
The phase difference between the microstrip lines can be controlled by moving the dielectric. As a result, a simple variable dielectric phase shifter that can control the phases of a plurality of microstrip lines with the same structure is realized.

The present invention also relates to the variable dielectric phase shifter, wherein the microstrip line has a meander line and has a meandering pitch or meandering width in a transmission direction continuously or stepwise. It is a microstrip line with a change.

That is, by sliding the dielectric, the effective length of the microstrip line is changed by utilizing the fact that the intersection length with the dielectric varies depending on the position. Since a different meander pattern is prepared for each microstrip line, the change of the effective length can be changed for each microstrip line. This makes it possible to control the phase difference between the microstrip lines by moving the dielectric. As a result, a simple variable dielectric phase shifter that can control the phases of a plurality of microstrip lines with the same structure is realized.

The present invention also relates to the variable dielectric phase shifter, wherein the microstrip line is a plurality of transmission lines, and the line width at the input end of each transmission line is reduced step by step. It is a tapered microstrip line in which the line width at the output end of each transmission line is gradually increased in order.

That is, by sliding the dielectric in the transmission direction of the microstrip line, the effective length of the microstrip line is changed by utilizing the fact that the influence of the dielectric varies depending on the position. This causes a phase difference between adjacent microstrip lines and facilitates control of the phase plane at the output end, so that a phased array antenna can be configured by attaching an antenna element to the output end. As a result, a variable dielectric phase shifter capable of controlling the phase plane with one structure is realized.

The present invention also relates to the variable dielectric phase shifter, wherein the dielectric is a tapered dielectric whose thickness decreases toward an end. Is what you do.

This makes it possible to suppress the reflection occurring at the edge of the dielectric plate. Accordingly, a dielectric having a high dielectric constant and a large thickness can be employed, so that the amount of phase shift per unit length can be increased, and the line length can be shortened. As a result, a small and low-loss variable dielectric phase shifter is realized.

[0020]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a perspective view showing a first embodiment of the present invention, in which 1 is a dielectric substrate with a ground plate, and 2 is a continuously variable width formed on the dielectric substrate 1. The microstrip line 3 is a dielectric plate placed on the microstrip line 2, 4 is an input terminal of the microstrip line 2, and 5 is an output terminal of the microstrip line 2. The microstrip line 2 has a tapered continuous change in width with respect to the transmission direction. The dielectric plate 3 is in close contact with the microstrip line 2 and can be slid in the transmission direction. When the dielectric plate 3 is slid to the left side (the input terminal 4 side) in FIG. 1 in the direction in which the line width is wide, the influence of the dielectric plate 3 on the line is weakened, and the phase shift amount is reduced. On the other hand, when the line is slid in the direction of the narrow line width on the right side (the output terminal 5 side) in FIG. Therefore, a variable dielectric phase shifter is realized by a configuration in which the dielectric plate 3 slides in the transmission direction.

FIG. 2 is a perspective view showing a second embodiment of the present invention, wherein 1 is a dielectric substrate with a ground plate, and 201 is a dielectric substrate 1 having a stepwise change in width. Microstrip line attached, 3 is microstrip line 2
Reference numeral 4 denotes an input terminal of the microstrip line 201, and reference numeral 5 denotes a microstrip line 20.
1 output terminal. The microstrip line 201 is provided with a discontinuous portion where the line width changes stepwise in the middle. The dielectric plate 3 is in close contact with the microstrip line 201 and can be slid in the transmission direction. When the dielectric plate 3 is slid to the left side (the input terminal 4 side) in FIG. 2, the intersection length between the wide part of the line width where the influence of the dielectric plate 3 is weak and the dielectric plate 3 becomes long, and the dielectric plate 3 Since the length of the intersection with the strongly affected portion is reduced, the phase shift amount is reduced. On the other hand, on the right side of FIG.
(Side), the crossing length between the narrow portion of the line width, which is greatly affected by the dielectric plate 3, and the dielectric plate 3 increases, so that the phase shift amount increases. Therefore, a variable dielectric phase shifter is realized by a configuration in which the dielectric plate 3 slides in the transmission direction.

FIG. 3 is a perspective view showing a third embodiment of the present invention, wherein 1 is a dielectric substrate with a ground plate, and 202 is a continuous change in the width formed on the dielectric substrate 1. Attached microstrip line, 203 is a microstrip line with the width of the microstrip line 202 reversed, 301 is a plurality of microstrip lines 202,
A rectangular dielectric plate capable of simultaneously covering a part of 203, 401 is an input terminal of the microstrip line 202, 402 is an input terminal of the microstrip line 203, 501 is an output terminal of the microstrip line 202, and 502 is a microstrip. This is the output terminal of the line 203. Both the tapered shapes of the microstrip lines 202 and 203 are adjusted so that the phase is linearly shifted in accordance with the amount of movement of the dielectric plate 301. Dielectric plate 30
Numeral 1 is closely attached to the two microstrip lines 202 and 203 so as to cover the same length, and can be slid in the transmission direction. The dielectric plate 301 is connected to the left side of FIG.
Side), the microstrip line 20
2 is a dielectric plate 301 on a wide portion where the influence of the dielectric is weak.
Is placed, the phase shift amount is reduced, and the dielectric plate 301 is placed on the narrow portion of the microstrip line 203 where the influence of the dielectric is large, so that the phase shift amount is increased and the phase shift amount is reduced. To increase. In this way, a variable dielectric phase shifter that realizes two phase shifters exhibiting completely opposite characteristics simultaneously with one configuration is realized.

FIG. 4A shows the result of numerically calculating the amount of phase shift in order to verify the characteristics of the variable dielectric phase shifter of FIG. FIG. 4B shows a top view of the variable dielectric phase shifter. In FIG. 4B, the dielectric substrate 1 has a total length of 50 mm, a thickness of 0.254 mm, a relative permittivity of 2.2,
The dielectric plate 301 to be put on the top has a total length of 25 mm and a thickness of 0.5
mm and the relative dielectric constant is 10.0. The microstrip line 202 has a trapezoidal shape having a width of the input terminal 401 of 2 mm and a width of the output terminal 501 of 0.2 mm. The microstrip line 203 has a width of the input terminal 402 of 0.2 m.
m, the output terminal 502 has a trapezoidal shape with a width of 2 mm. FIG.
The horizontal axis x in (a) is the distance between the left end of the dielectric plate 301 and the left end of the dielectric substrate 1, and indicates the position of the dielectric plate 301. The vertical axis in FIG. 4A indicates the amount of phase delay, and indicates the amount of phase shift at the output terminals 501 and 502. From the figure, it can be seen that the dielectric plate 30 of the variable dielectric phase shifter
As 1 moves from the left end (the input terminals 401 and 402 side) to the right end (the output terminals 501 and 502 side), it can be seen that the phases of the two change symmetrically. It can be seen that the phase shift characteristic is exhibited, and the effectiveness of this configuration can be confirmed.

FIG. 5 is a perspective view showing a fourth embodiment of the present invention, wherein 1 is a dielectric substrate with a ground plane, 204 is a linear microstrip line formed on the dielectric substrate 1, 205 Is a microstrip line formed on the dielectric substrate 1 and having a continuous change in the line direction, 301 is a rectangular dielectric plate capable of simultaneously covering a part of a plurality of lines, and 403 is a microstrip line 204 404 is an input terminal of the microstrip line 205, 503 is an output terminal of the microstrip line 204, and 504 is an output terminal of the microstrip line 205. The dielectric plate 301 is in close contact with the two microstrip lines 204 and 205, and can slide in the transmission direction. Dielectric plate 30
5 is shifted to the left side (toward the input terminals 403 and 404) in FIG. 5, the cross-shift length of the microstrip line 205 with the dielectric plate 301 increases, so that the phase shift amount increases with respect to the microstrip line 204. If the microstrip line 205 is slid to the right (toward the output terminals 503 and 504), the dielectric crossing length of the microstrip line 205 becomes closer to that of the microstrip line 204, so that the phase shift amount is reduced and the phase difference between the two is reduced. Thus, 2
A variable dielectric phase shifter that can easily adjust the phase difference between the two lines is realized.

FIG. 6 is a perspective view showing a fifth embodiment of the present invention, in which 1 is a dielectric substrate with a ground plate, and 202 is a structure in which the width formed on the dielectric substrate 1 changes continuously. A microstrip line 203, a microstrip line in which the change in the width of the microstrip line 202 is reversed, and 302, a plurality of microstrip lines 202,
A rectangular dielectric plate having a tapered shape capable of simultaneously covering a part of 203 and decreasing in thickness toward both ends, 401 is an input terminal of the microstrip line 202, and 402 is an input terminal of the microstrip line 203 A terminal 501 is an output terminal of the microstrip line 202, and a reference numeral 502 is an output terminal of the microstrip line 203. The microstrip line 202 has a tapered continuous change in width with respect to the transmission direction, and the microstrip line 203 has a line width change opposite to that of the microstrip line 202 in FIG.
The taper shape of both the microstrip lines 202 and 203 is adjusted so that the phase is linearly shifted according to the amount of movement of the dielectric plate 302. The operation principle is the same as that of the third embodiment shown in FIG. 3, but the thickness of the side of the dielectric plate 302 orthogonal to the microstrip lines 202 and 203 is tapered, so that the thickness of the boundary of the dielectric plate 302 is increased. The resulting microstrip lines 202, 20
3 can be suppressed. Therefore, a variable dielectric phase shifter having lower loss than that of the third embodiment is realized.

FIG. 7 is a top view showing a sixth embodiment of the present invention, wherein 1 is a dielectric substrate with a ground plane, and 206 is a meander formed on the dielectric substrate 1 with a meandering width varied. A microstrip line 207; a microstrip line 207; a microstrip line composed of a meander line in which a meandering width of the microstrip line 206 and the meander line are reversed;
07, a rectangular dielectric plate capable of simultaneously covering a portion of the reference numeral 07, an input terminal 405 of the microstrip line 206, an input terminal 406 of the microstrip line 207, an output terminal 505 of the microstrip line 206, and a microstrip 506. Output terminal of the line 207. The meander line of the microstrip line 206 is changed so that the meandering width gradually narrows with respect to the transmission direction. The meandering width is changed. The dielectric plate 301 includes two microstrip lines 206,
It is in close contact with the meander line 207 and can be slid back and forth in the transmission direction. The dielectric plate 301 is connected to the left side of FIG.
Side), the microstrip line 20
The meander line 6 has a dielectric plate 30
Since 1 is placed, the intersection length between the dielectric plate 301 and the microstrip line 206 increases, so that the phase shift amount increases. Conversely, in the meander line of the microstrip line 207, since the dielectric plate 301 is placed in a portion having a small meandering width, the intersection length is shortened, so that the amount of phase shift is reduced. In this way, by realizing two phase shifters exhibiting completely opposite characteristics simultaneously in one configuration, a variable dielectric phase shifter capable of easily controlling the phase difference between the microstrip lines 206 and 207 is provided. Is realized.

In the meander line of the microstrip line, the meandering pitch or meandering width can be varied continuously or stepwise with respect to the transmission direction.

FIG. 8 is a top view showing a seventh embodiment of the present invention, wherein 1 is a dielectric substrate with a ground plate, 211 to 21.
Reference numeral 4 denotes a microstrip line formed on the dielectric substrate 1 and having a continuous variation in width; 301, a rectangular dielectric plate capable of simultaneously covering a part of the plurality of microstrip lines 211 to 214; 414 are input terminals of the microstrip lines 211 to 214, respectively.
11 to 514 are microstrip lines 211 respectively.
To 214, microstrip lines 211 to 211
Each of the microstrip lines 214 has a different taper shape, the microstrip line 211 has the widest line width of the input terminal 411, and the narrowest line width of the output terminal 511.
And the input terminal 414 is the narrowest and the output terminal 51
4 is the widest track. Microstrip line 21
2 and 213 have an intermediate shape between the microstrip lines 211 and 214, the input terminals 411 to 414 are gradually reduced in line width in the order of the input terminals 411 to 414, and the output terminals 511 to 514 are output terminals. 511 to 51
The line width gradually increases in the order of 4. When the dielectric plate 301 is placed on the left end (the input terminals 411 to 414 side) of the dielectric substrate 1, when the input terminals 411 to 414 are fed in phase,
An equal phase difference occurs between the lines adjacent to the microstrip lines 211 to 214, and the phase planes of the output terminals 511 to 514 can be inclined. On the other hand, the right end (output terminal 5
11 to 514), a phase plane having an opposite inclination is formed. When the dielectric plate 301 is slid to the center, the phase difference disappears, and all the output terminals 511 to 514 The phase planes are equiphase. Since the phase plane can be easily controlled, a phased array antenna can be configured by attaching an antenna element to the output terminals 511 to 514 of the variable dielectric phase shifter. In this way, a variable dielectric phase shifter that can control the phase plane with one structure is realized.

[0030]

As described above, according to the present invention, there is provided a variable dielectric phase shifter which can easily control the phase difference between lines without having to control the phase of each line individually. You can do it.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a first embodiment of the present invention.

FIG. 2 is a perspective view showing a second embodiment of the present invention.

FIG. 3 is a perspective view showing a third embodiment of the present invention.

FIG. 4 is an explanatory diagram showing a phase shift characteristic according to a third embodiment of the present invention.

FIG. 5 is a perspective view showing a fourth embodiment of the present invention.

FIG. 6 is a perspective view showing a fifth embodiment of the present invention.

FIG. 7 is a top view showing a sixth embodiment of the present invention.

FIG. 8 is a top view showing a seventh embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 dielectric substrate with ground plate 2 microstrip line 3 dielectric plate 4 input terminal 5 output terminal

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Toshikazu Hori 2-3-1 Otemachi, Chiyoda-ku, Tokyo F-term in Nippon Telegraph and Telephone Corporation 5J012 GA12

Claims (7)

[Claims] 1. A variable dielectric transfer device comprising: a microstrip line formed on a dielectric substrate; and a dielectric covering a part of an upper surface of the microstrip line and disposed so as to be freely movable on the substrate. In the phase shifter, the microstrip line is a microstrip line in which the line characteristics are changed continuously or stepwise in the transmission direction. 2. The variable dielectric phase shifter according to claim 1, wherein said microstrip line is a microstrip line having a line width continuously or stepwise changed in a transmission direction. A variable dielectric phase shifter, characterized in that: 3. The variable dielectric phase shifter according to claim 1, wherein said microstrip line is a microstrip line composed of two or more parallel lines. Dielectric phase shifter. 4. The variable dielectric phase shifter according to claim 1, wherein the microstrip line is two or more transmission lines, and a distance between centers of two adjacent lines is a transmission direction. A variable dielectric phase shifter characterized by a microstrip line that changes smoothly with respect to the phase shifter. 5. The variable dielectric phase shifter according to claim 1, wherein the microstrip line has a meander line, and has a meandering pitch or meandering width in a transmission direction. A variable dielectric phase shifter, characterized in that the variable dielectric phase shifter is a microstrip line having a stepwise or stepwise change. 6. The variable dielectric phase shifter according to claim 1, wherein the microstrip line is a plurality of transmission lines, and a line width of an input end of each transmission line is sequentially changed. A variable dielectric phase shifter, which is a tapered microstrip line in which the line width at the output end of each transmission line is gradually narrowed in order. 7. The variable dielectric phase shifter according to claim 1, wherein the dielectric has a tapered shape in which the thickness of the dielectric decreases toward the end. A variable dielectric phase shifter, characterized by being a dielectric material.