JPS61172401A - Semiconductor phase shifter - Google Patents

Abstract

PURPOSE:To obtain a broad band semiconductor phase shifter by constituting a 3dB hybrid coupler with a triplate type strip line using a 3-layer dielectric board and a 3dB power distributor and a balanced modulator with a slot line constituted on both faces of the ground conductor of the triplate type strip line. CONSTITUTION:After a radio wave incident from the 2nd input/output terminal 22 is distributed by the 3dB power distributor 44 into equal power, the radio wave propagates the 1st and 2nd slot lines 46, 47 provided to both faces of the 1st ground conductor 32 and the 2nd ground conductor 33 and subjected to amplitude modulation proportional respectively to sinomega1t, cosomega1t by the 1st balanced modulator 36 and the 2nd balanced modulator 38. Then the propagation mode is converted again into the triplate type strip line, the waves are combined in terms of vectors by a phase difference of 90 deg. at a broad band wide coupling line type 3dB hybrid coupler 34, an output with equal amplitude whose phase is changed continuously for 360 deg. appears at the 1st input/output terminal 5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a phase shifter that continuously changes the phase of microwaves, and more particularly, to a semiconductor phase shifter that has a wider bandwidth.

[Conventional technology]

Figure 3 shows, for example, the Institute of Electronics and Communication Engineers technical research report (MW80-
102) A structural diagram showing the conventional double-balanced modulator shown in FIG. 102, which can be used as an analog type semiconductor phase shifter by simply changing the method of applying a bias voltage to the diode.

In the figure, 1 is a dielectric substrate, 2 is a strip conductor of the microstrip line, 3 is the ground conductor of the microstrip line, 4 is a branch line type 3dB hybrid coupler, 5 is a first input/output terminal, 6 is a matching termination terminal, and T is a termination resistor connected to the above-mentioned matching termination terminal 6, one end of which is connected to the above-mentioned ground conductor 3. 8.9 are the first coupling terminal and second coupling terminal, respectively, where the radio waves incident from the first input/output terminal 5 appear with equal power distribution with a phase difference of 90', and 10.11 are the ground terminals, respectively. A first annular slot line and a second annular slot line made of a gap provided in the conductor 3, 12. 13 are the above-mentioned first and second annular slot lines IQ, 11, respectively.
14, 15, 16, 17 are the first conductors surrounded by the first and second annular slot lines 10.11. Surface 18. A diode having one electrode connected to the second conductor surface 19, the diode 14.1
5 and 16.17 diodes form a pair, each pair being connected with opposite polarity. The other electrodes of the diode 14.15 and the diode 16.17 are connected to the first and second annular slot lines 1, respectively.
5&C to bridge the gap of 0.11, and the first one above.
The above-mentioned ground conductor 3Ki is connected to sandwich the second branch slot line 12, 13. Note that the diode 14
, 15 is applied to the first conductor surface 18.
The bias applied to the diodes 16 and 17 is applied via the second conductor surface 19 and the ground conductor 3, but is not shown in FIG.

20 is a Wilkinson type 3 dB power divider, 21 is a resistor, and 22 is a second input/output terminal. Note that the first branch line type 3 dB hybrid coupler 4 described above
The strip conductors 2 of the second coupling terminals 8 and 9 are connected to the first and second annular slot lines 10 described above, respectively.
．． 11, the first and second distribution terminals 2 are arranged orthogonally to the second input/output terminal 22, and the radio waves incident on the 3dB power divider 20 from the second input/output terminal 22 appear with the same phase and amplitude.
3.24 strip conductors 2 each have the above-mentioned first
By arranging it perpendicularly to the second branch slot line 12, 13, a smooth conversion between waves propagating on the microstrip line and waves propagating on the slot line is achieved.

A conventional double-balanced modulator is constructed as described in 5 above, and becomes an analog-shaped semiconductor phase shifter with a phase variable range of 360° due to the bias application method to the diode described below.

FIG. 4 is a diagram for explaining the operation of a balanced modulator out of the double balanced modulator, and shows the state seen from the ground conductor 3 side of FIG. 3.

Bias terminal 2 of bias circuit 25 made of conductor wire
6 is a positive voltage +v0, the diode 14 is forward biased and has low impedance, and the diode 15 is reverse biased and has high impedance. The wave generated by the first annular slot line 10
propagates clockwise, is converted into a microstrip line, and appears at the first coupling terminal 8. On the other hand, the bias voltage V is set to a negative voltage -■. Then, the diodes 14 and 15 are each in a biased state opposite to the above, and the wave incident from the first branch slot line 12 propagates counterclockwise through the first annular slot line 10, resulting in micros) IJ It is converted into a tube line and appears at the first coupling terminal 8. As described above, the propagation direction of the radio waves propagating through the annular slot line differs depending on the polarity of the bias voltage applied to the bias terminal 26, and the two have opposite phases at the conversion section with the microstrip line. Therefore, the phase of the radio wave appearing at the first coupling terminal 8 is reversed by 180 degrees by changing the bias voltage from +vo to -Vo.

FIG. 5 is a vector diagram showing an outline of the relationship between the amplitude and one phase of the radio waves appearing at the bias terminal and the first coupling terminal 8. In this way, the 1-balanced modulator has a bias voltage of +■. By continuously changing from -voK to -voK, it is possible to control the amplitude to an arbitrary value while maintaining the phase of the output radio wave at 00 and 180 degrees.

FIG. 6 shows a phase change range 360 using a double-balanced modulator.
FIG. 2 is a diagram for explaining the operation of an analog phase shifter of 20°.

The bias terminal of the first balanced modulator 26 is assumed to be 25, and the bias terminal of the second balanced modulator 2T is assumed to be 28. Here, the voltage applied to the bias terminal 25 of the first balanced modulator 26 is set so that the time change in the amplitude of the output voltage of the balanced modulator shown in FIG. 4 is proportional to sinω1tK, where ω1 is the angular velocity and t is the time. Drive to 5. On the other hand, the voltage applied to the bias terminal 28 of the second balanced modulator 27 is set so that the time change in the amplitude of the output voltage is proportional to cosω1tK with a phase difference of 90° with respect to the above output voltage. move.

When the voltage applied to the diode is driven with such a time change, the power of the radio waves incident on the 3 dB power divider 20 from the second input/output terminal 22 is divided into two equal parts, and then the power is divided into two equal parts.
The signals are propagated through the second balanced modulator 26 and 27, power-combined by the 3 dB hybrid coupler 4 with a phase difference of 90 degrees, and appear at the first input/output terminal 5. As shown in FIG. 7, the radio waves appearing at the first input/output terminal 5 are
It can be represented by a solid line as a composite vector of the radio wave passing through the second balanced modulator 26 (dotted line vector) and the radio wave passing through the second balanced modulator 27 (dotted line vector).

In other words, the combined vector of the outputs of the first and second balanced modulators 26 and 27 becomes a vector whose amplitude is constant and whose phase changes continuously at an angular velocity ω1 according to changes in the amplitude of each output voltage, and the phase change range is A 360° semiconductor phase shifter can be realized ◇ [Problems to be solved by the invention] In the conventional semiconductor phase shifter as described above, a slot line is constructed using a ground conductor of a microstrip line. Therefore, as a 3dB hybrid coupler, a branch line type 3dB coupler made of microstrip lines is recommended.
A hybrid coupler and an iterated digital type 3dB hybrid coupler are used, but the former has a usable band of 1.
Since the latter is composed of a non-uniform medium, the propagation constants of the even mode and odd mode of the coupled line are different, resulting in a narrow usable band, resulting in a band of one octave or more. That's difficult. The output of the balanced modulator is
Read-only memory (ROM) is used to drive the bias voltage.
, it is possible to obtain the required output voltage over a wide band by using a digital-to-analog converter (D/A converter), but the bandwidth of the 3 dB hybrid coupler makes it difficult to There was a problem in that the bandwidth used was limited.

The present invention has been made to solve this problem, and aims to provide a semiconductor phase shifter having a phase variable range of 360'' over a wide band of 1 octave or more.

[Means for solving problems]

The semiconductor phase shifter according to the present invention is a coupled line type 3 dB triple plate strip line using a three-layer dielectric substrate.
Configure a hybrid combiner, balance modulator and 3dB
The power divider is composed of a slot line consisting of opposing slits provided on both sides of a ground conductor of a triplate strip line, and is integrated with a three-layer dielectric substrate.

[Effect]

In this FIA, a coupled line type 3 dB hybrid coupler composed of triplate strip lines has broadband performance, and slot lines provided on both sides of the triplate strip line and the ground conductor of the triplate strip line are used. Since the conversion is also performed smoothly, wideband performance can be obtained.

〔Example〕

FIG. 1 (N is a perspective view showing an embodiment of the present invention,
FIG. 1(E) is a sectional view taken along line AA in FIG. 1(A).

In order to facilitate the explanation of the structure of a semiconductor phase shifter consisting of a three-layer dielectric substrate shown in FIG. 1 (Al, K, and
FIG. 3 is a perspective view showing a three-layer dielectric substrate separated.

In FIG. 2, 29 is a dielectric upper layer substrate, 30 is a dielectric middle layer substrate, 31 is a dielectric lower layer substrate, 32 is the first ground conductor of the triplate strip line, and 33 is the second ground conductor of the triplate strip line. 34 is a wide surface coupled line type 3 dB hybrid coupler constructed by providing strip conductors 35 on both sides of the above-mentioned dielectric intermediate substrate 30;
36 is the above-mentioned first ground conductor 32 and second ground conductor 33
A first balanced modulator consisting of a slot line 37 consisting of opposing slots provided in the slot line 37;
This is a second balanced modulator composed of The first and second balanced modulators 36.38 described above are connected to the first ground conductor 32.38, respectively. Two diodes 39 are connected to each surface of the second ground conductor 33 with opposite polarities, and bias terminals 40, 41, 42 are connected to these diodes 39 via the conductor surrounded by the annular slot line 37 and the ground conductor. A bias is applied from .43. 44 is the above-mentioned first and second ground conductor 32□
A slot line 45 consisting of opposing slits provided in 33, and a Wilkinson type 3D formed by '' in the resistor 21.
B is a power divider. The slot line 45 described above is the first
and first and second slot lines 46,47 each consisting of two pairs of slots extending from the three branches of the second balanced modulator 36,38, and these two slot lines 46.
．． 47 is connected to another slot line 48, thereby forming three branches. Also, resistor 2
1 is at a position 1/4 wavelength from the above 3-branch part [,
The gap between one slot line 46 and the other slot line 4
The conductor surface 3 bridges the slit 49 connecting the slit 7.
2.33 is connected.

In the semiconductor phase shifter configured as described above, the second
The radio waves incident from the input/output terminal 22 of the first ground conductor 32. Second
It propagates through the first and second slot lines 46 and 47 provided on both sides of the ground conductor 33, and the first balanced modulator 36 and the second balanced modulator 38 each transmit 5 inches (all
, Cog (after undergoing amplitude modulation proportional to aj1tK,
The propagation mode is converted to the triplate strip line again, and vectorially synthesized with a phase difference of 90° by the wide-band wide surface coupled line type 3 dB hybrid coupler 34.
At the input/output terminal 5 of , an output whose phase changes continuously over 360 degrees with equal amplitude appears. First and second balanced modulator 3
The output voltage amplitude of 6.38 is read-only memory (R
If a diode bias voltage driving method using OM) is used, it is possible to obtain a value proportional to the required 5tnQ+1t I cosω1t. Therefore, it is necessary to use a wide-band, wide-plane coupled line type 3 dB hybrid coupler that does not have the fundamental isolation and frequency characteristics.
[In order to configure] using a three-layer dielectric substrate that integrates a triplate strip line and a slot line,
It is possible to obtain a broadband semiconductor phase shifter with less reflection due to discontinuities.

In the above embodiment, a case has been described in which the diode is used as a phase shifter with a phase change range 360', but it goes without saying that the diode can be driven with a pulse voltage and used as a four-phase phase modulator.

〔Effect of the invention〕

As explained above, this invention has a 3dB hybrid coupler using a triplate strip line using a 3ffifJj electrical board, and a 3dB power divider and balanced modulation using a slot line configured on both sides of the ground conductor of the triplate stripline. By configuring the phase shifter, a broadband semiconductor phase shifter can be obtained.

[Brief explanation of drawings]

FIG. 1 (A) is a perspective view showing the structure of one embodiment of the present invention, FIG.
The figure is a perspective view for explaining the structure of a semiconductor phase shifter composed of a three-layer dielectric substrate according to the present invention, FIG. 3 is a perspective view showing the structure of a conventional double-balanced modulator, and FIG. is a diagram for explaining the operation of a balanced modulator, Figure 5 is a vector diagram showing the relationship between the bias voltage and the amplitude 1 phase of the radio wave appearing at the first coupling terminal, and Figure 6 is a diagram for explaining the operation of a double balanced modulator. FIG. 7 is a diagram for explaining the operation of an analog phase shifter having a phase change range of 360 degrees. FIG. 7 is a composite vector diagram of radio waves passing through the first and second balanced modulators. In the figure, 29 is a dielectric upper layer substrate, 30 is a dielectric middle layer substrate, 31 is a dielectric lower layer substrate, 32 is a first ground conductor, 3
3 is a second ground conductor, 34 is a wide surface coupled line type 3 dB hybrid coupler, 36 is a first balanced modulator, 37.45
．． 48 is a slot line, 38 is a second balanced modulator, 39
is a diode, 40 to 43 are bias terminals, 44 is 3d
B power divider, 46 is the first slot line, 47 is the second
0 slot line, 49 is a slit. Note that the same reference numerals in each figure indicate the same or corresponding parts. Patent applicant Mitsubishi Electric Corporation *1 time (A) Figure 4 Figure 6

Claims (1)

[Claims] The first and second balanced modulators of the same configuration are connected to the two terminals of the 3dB hybrid coupler that distribute equal power with a phase difference of 90°, and the outputs of these two balanced modulators are connected to the 3dB power divider. In an analog phase shifter having a connected configuration and driven such that temporal changes in amplitude of the outputs of the first and second balanced modulators are proportional to a sine function and a cosine function, respectively, the 3 dB hybrid The coupler is composed of a wide surface coupled line type 3dB hybrid coupler using a triplate strip line made of a three-layer dielectric substrate, and the first and second balanced modulators are both connected to the triplate strip line. A slot line consisting of a pair of slits provided at opposite positions on both sides of the ground conductor is arranged in a ring shape, and two slot lines each are arranged at opposite positions on the opposite first and second conductor faces surrounded by the ring-shaped slot line. One electrode of the diodes is connected closely so that the diodes have opposite polarities, and the other electrode of the four diodes connected to opposite positions of the first and second conductor surfaces is A slot formed by the pair of slot lines is connected to the conductor surface so as to bridge the gap between the pair of slot lines, and further extends the transmission line from between the two diodes to the outside of the annular slot line. The 3 dB power divider is configured by providing three branch parts for connecting the lines, and the 3 dB power divider is connected to the first branch part.
and two pairs of slot lines each extending from the three-branch section of the second balanced modulator are connected, and another slot line is connected to this connection position to form a three-branch section. , at a position a quarter wavelength away from the three-branch section toward the first and second balanced modulators, the gap of one slot line and the gap of the other slot line are connected to the first slot line.
and a second conductor surface with a pair of gaps, and a resistor is connected to the conductor surface to bridge the gap, and the 3dB hybrid coupler and the first and second balanced The connection between the modulator, the 3 dB power divider, and the input/output triplate stripline is formed by a triplate stripline and a pair of slots formed on both sides of the ground conductor of the triplate stripline. The device is characterized by comprising means for applying a bias to the diode through a total of four conductor surfaces surrounded by the annular slot line constituting the first and second balanced modulators. semiconductor phase shifter.