CN201153148Y - Microwave phase shift device based on plane type micro-strip transmission line - Google Patents

Abstract

The utility model relates to a microwave phase shifter based on a planar left-handed microstrip transmission line structure. The problems of large volume, large loss, small power capacity and the like existing in the existing microwave phase shifter are solved. The microwave phase shifter of the utility model is formed by loading a PIN switch on the left-hand microstrip transmission line unit. The specific scheme is: choose to install a pair of PIN switches on a pair of sidebands or a pair of interfingers located at symmetrical positions; signal input and output ports are respectively located at symmetrical positions of a pair of sidebands. In this way, the current passing through a single interfinger or the PIN switch on the sideband is only a small part of the current passing through the entire phase shifter, thereby greatly improving the power capacity of the phase shifter; in addition to the characteristics of high power capacity , the phase shifter also has other advantages, such as small loss, small size, fast switching speed, convenient manufacturing, easy integration with MMIC circuits, etc.; it has great advantages in radar and phased antenna array applications.

Description

Microwave phase shifter based on planar left-handed microstrip transmission line

technical field

The utility model relates to a microwave phase shifter, specifically a microwave phase shifter based on a planar left-handed microstrip transmission line.

Background technique

Microwave phase shifters are used in many fields, such as radar systems, satellite communication systems and phased array antenna arrays. There are many types of phase shifters. According to the materials used, there are generally five categories: ferrite phase shifters, ferroelectric phase shifters, semiconductor diode phase shifters, gallium arsenide MMIC phase shifters and MEMS phase shifters. phase device.

In 1991, Artech house published "Microwave and Millimeter Wave Phase Shifters". The first volume of the book, Dielectric and Ferrite Phase Shifters, introduced the main types, design, production and application of ferrite phase shifters in detail. The ferrite phase shifter mainly uses an external magnetic field to change the magnetic permeability of the ferrite in the waveguide, thereby changing the phase velocity of the electromagnetic wave to obtain different phase shifts. Its advantages are: broadband and large power capacity; its disadvantages are: large volume, large loss, and slow switching speed.

In 2000, Kozyre et al published the paper "Application of Ferroelectrics in Phase Shifters Design" at the IEEE International Conference on Microwave Theory and Technology ("Application of Ferroelectrics in Phase Shifters Design", A.Kozyrev, V.Osadchy, A.Pavlov , L. Sengupta, 2000 IEEE MTT-S Digest. P1355-1358). The ferroelectric phase shifter mainly changes the dielectric constant of the medium by changing the magnitude of the DC bias applied to the ferroelectric, thereby changing the phase velocity of the microwave signal and realizing phase shifting. Its advantages are: simple structure, small size, light weight, small loss, and fast response; the disadvantage is: small power capacity.

In 1976, the microstrip circuit writing group of Tsinghua University wrote the book "Microstrip Circuit". The basic principles and design methods of several semiconductor PIN diode-based phase shifters. No matter which structure is adopted, the principle of the PIN diode-based phase shifter is to use the two different switching states of the PIN diode when it is forward-biased and reverse-biased, so that a transmission line is turned on or off to achieve phase shifting. Its advantages are: small size, easy to use digital signal control, fast response speed; disadvantages: large power consumption, relatively small power capacity.

In May 2001, Ellinger et al. published the paper "Compact Reflective-TypePhase-Shifter MMIC for C-Band Using Lumped Element Coupler" on IEEE Transaction on MTT. a Lumped-Element Coupler" Frank Ellinger, Rolf Vogt, Werner Bechtold, IEEE Transaction on Microwave Theory and Techniques, VOL.49, NO.5, MAY 2001). The phase shifter based on gallium arsenide MMIC technology mainly adopts a reflective structure, and its principle is to obtain reflection coefficients of different phases by selecting different reflective terminals, thereby realizing phase shifting. Its advantages are: small size, fast response; disadvantages: large insertion loss, small power capacity.

In June 2002, Rebeiz et al published the paper "RF MEMS phase shifters: design and applications" on IEEE Microwave ("RF MEMS phase shifters: design and applications" Rebeiz G.M, Guan-LengTan, Hayden J.S, Microwave Magazine, IEEE Volume 3, Issue 2, June 2002 Page(s): 72-81). The MEMS phase shifter uses MEMS radio frequency switches to change the size of the load capacitance paralleled between the central conduction band of the transmission line and the ground, thereby changing the equivalent line capacitance of the entire structure, and then changing the phase velocity of the microwave signal to achieve phase shifting. Its advantages are: small loss, large power capacity; disadvantages: slow switching speed, low reliability, and short service life.

The above literature shows that although ferrite phase shifters and MEMS phase shifters have large power capacity, their switching speed is slow; ferroelectric material phase shifters, semiconductor diode phase shifters, and gallium arsenide MMIC phase shifters are small in size, The switching speed is faster, but generally the power capacity is smaller.

Regarding left-handed transmission line theory:

In 2006, John wiley&son Press published a book by TATSUO Itoh of the University of California at Los Angeles and Ecole Polytechnique de Montreal of Canada. ) book on Electromagnetic Metamaterials by CHRISTOPHE Caloz. As the dual of the right-handed transmission line, the theory and application of the left-handed transmission line are introduced systematically for the first time.

Utility model content

The purpose of this utility model is to overcome the shortcomings of the existing microwave phase shifter such as: large volume, large loss, small power capacity, etc., to provide a compact structure based on the structure of the planar left-handed microstrip transmission line. High power capacity microwave phase shifter.

The specific structural design scheme is as follows:

The left-hand microstrip transmission line phase shifter of the utility model is formed by loading a PIN switch on the left-hand microstrip transmission line unit.

The left-hand microstrip transmission line unit is designed on the PCB board. The first and third layers of the PCB board are copper conductors with a thickness of (0.004mm); the middle layer is a dielectric board with a dielectric constant (1.07-13.6) and a thickness of is 0.254mm; on the first layer, a planar metal microstrip interdigitated structure is made to form an interdigitated capacitor; the interdigitated gap of the interdigitated capacitor is 0.1~0.3mm, and the interdigitated width is 0.1~0.8mm; There is a pair of sidebands perpendicular to the intersecting fingers at the end, and the width of the sidebands is 0.1-0.5mm; the ground of the left-hand microstrip transmission line is composed of the metal of the third layer; at least one sideband or any intersecting finger on the first layer is selected , using via technology to connect the interdigitation or sideband to the third layer metal ground of the PCB board to form an inductor through a short-circuit nail, the diameter of the via hole is (0.1-0.8);

Select a pair of interdigitated fingers located at symmetrical positions, truncate them at the central symmetrical position of the interdigitated fingers, and install a pair of positive doping/intrinsic/negative doping diode (PIN) switches at the truncation; signal input and output The ports are respectively located at symmetrical positions of a pair of sidebands. By controlling the above-mentioned positive doping/intrinsic/negative doping diode (PIN) switch, the phase control of the electromagnetic wave flowing through the left-hand unit is realized. Using the above-mentioned structure, the utility model realizes a microwave phase shifter based on the left-hand microstrip transmission line.

It is also possible to select a pair of outermost intersecting fingers located at symmetrical positions, truncate them at the central symmetrical position of the pair of intersecting fingers, and install a pair of positively doped/intrinsic/negatively doped diodes (PIN )switch;

It is also possible to select a pair of sidebands to be truncated at the central symmetrical position, and install a pair of positive doping/intrinsic/negative doping diode (PIN) switches at the truncated position.

In the present invention, the positive doping/intrinsic/negative doping diode (PIN) switch of the phase shifter is installed on the interfingers or sidebands of the left-hand transmission line, so that the positive doping through a single interfinger or sideband The current of the hybrid/intrinsic/negative doped diode (PIN) switch is only a small part of the current through the entire phase shifter, so the power capacity of the phase shifter has been greatly improved; in addition to the characteristics of high power capacity , the phase shifter also has other excellent electromagnetic properties, such as small size, low loss and so on. In particular, using the method of installing switches on the fingers of the left-hand microstrip transmission line to design a phase shifter can design a phase shifter with fast switching speed and large power capacity; at the same time, using the left-hand transmission line to design a phase shifter does not require any active source device, does not require energy conversion, can be directly produced on ordinary PCB boards, and can be directly produced together with microwave circuits; easy to integrate with MMIC circuits, etc.; it has great advantages in radar and phased antenna array applications.

Description of drawings

FIG. 1 is a three-dimensional schematic diagram of a left-handed microstrip transmission line phase shifter according to Embodiment 1 of the present invention.

FIG. 2 is a schematic top view of FIG. 1 .

FIG. 3 is a schematic left view of FIG. 1 .

FIG. 4 is a schematic diagram of the phase shift degree of the left-handed microstrip transmission line phase shifter in Embodiment 1 of the present invention.

5 is a schematic diagram of the voltage standing wave ratio when the switch of the phase shifter of the left-hand microstrip transmission line in Embodiment 1 of the present invention is closed.

6 is a schematic diagram of the voltage standing wave ratio when the phase shifter switch of the left-hand microstrip transmission line in Embodiment 1 of the present invention is turned on.

7 is a three-dimensional schematic diagram of a phase shifter for a left-handed microstrip transmission line in Embodiment 2 of the present invention.

FIG. 8 is a schematic top view of FIG. 7 .

FIG. 9 is a schematic left view of FIG. 7 .

Fig. 10 is a schematic diagram of the phase shift degree of the left-hand microstrip transmission line phase shifter in Embodiment 2 of the present invention.

11 is a schematic diagram of the voltage standing wave ratio when the switch of the phase shifter of the left-hand microstrip transmission line in Embodiment 2 of the present invention is closed.

12 is a schematic diagram of the voltage standing wave ratio when the switch of the phase shifter of the left-hand microstrip transmission line in Embodiment 2 of the present invention is turned on.

FIG. 13 is a three-dimensional schematic diagram of a phase shifter for a left-handed microstrip transmission line in Embodiment 3 of the present invention.

FIG. 14 is a schematic top view of FIG. 13 .

FIG. 15 is a schematic left view of FIG. 13 .

16 is a schematic diagram of the phase shift degree of the left-hand microstrip transmission line phase shifter in Embodiment 3 of the present invention.

Fig. 17 is a schematic diagram of the voltage standing wave ratio when the switch of the phase shifter of the left-hand microstrip transmission line in Embodiment 3 of the present invention is closed.

Fig. 18 is a schematic diagram of the voltage standing wave ratio when the phase shifter switch of the left-hand microstrip transmission line in Embodiment 3 of the present invention is turned on.

Detailed ways

Below in conjunction with accompanying drawing, the utility model is further described by embodiment.

Example 1:

Referring to Figure 1, Figure 2 and Figure 3, the left-hand microstrip transmission line phase shifter is designed on the PCB board, using Rogers RT/TMM 10i alumina dielectric substrate with a layer area of 8mm×6mm; the first layer, the second layer of the PCB The third layer is conductor copper with a thickness of (0.004mm), the third layer of metal constitutes the ground 1 of the left-hand transmission line, and the middle layer is a dielectric layer 2 with a dielectric constant of 9.8 and a thickness of 0.254mm; Make interdigitated capacitor 3 in the area of 8mm×6mm in the center of the first layer conductor copper area 2.28mm×1.9mm. Width 0.1mm, interdigital spacing 0.1mm, interdigital length 1.14mm, one on each of the outermost interdigital fingers at both ends, and a pair of APD0810-000PIN switches 4 from SKYWPRKS Company are installed on the two interdigital fingers (normal temperature 25°C The lower power capacity is 2.5W), the switch position is 0.41mm away from the root of the interdigitation, the switch size is 0.35mm×0.35mm×0.127mm, each interdigitation end is connected with a sideband 5, the width of the sideband is 0.3mm, and the length of the sideband is 1.9mm mm, the input and output ports 6 feeders are respectively located in the center of the two interdigitated sidebands, and the width of the feeder is 0.25mm. On the edge band of the interdigitated structure of the upper layer, it is connected to the ground wire of the lowest layer through two short-circuit nails 7 (solid cylindrical metal copper, radius 0.15 mm, height 0.254 mm). Both short-circuit nails pass through the dielectric layer vertically. The projection of the short-circuit nails on the upper metal surface is a circle. The center of the circle is 0.2mm away from the upper and lower edges of the sideband, and the circle is tangent to the edge of the sideband.

The electrical performance that can be achieved by this specific implementation is: center frequency 9.5GHz, working bandwidth 2GHz, phase shift 11.25° (±0.75°) when a pair of switch states change at the same time, see Figure 4, Figure 5 and Figure 6.

Since this structure has 5 pairs of 10 interfingers in total, the current passing through the PIN switch on a single interfinger is only about 1/10 of the current passing through the entire phase shifter. After the power capacity test, it is found that the phase shifting of the left-hand microstrip transmission line The power capacity of the switch can reach 28.2W, which is 11.28 times that of a single PIN switch.

Example 2:

Referring to Figure 7, Figure 8 and Figure 9, the left-hand microstrip transmission line phase shifter is designed on the PCB board, using Rogers RT/duroid 5880 dielectric substrate with a layer area of 8mm×6mm; the first and third layers of the PCB board are Conductor copper with a thickness of (0.004mm), the third layer of metal constitutes the ground 1 of the left-hand transmission line, the middle layer is a dielectric layer 2 with a dielectric constant of 2.2, and its thickness is 0.254mm; Make an interdigitated capacitor 3 in the center of the copper conductor on the first layer of 3.915mm×2.3mm, and the number of interdigitated fingers is 4, that is, there are 4 interdigitated fingers in each sheet, 2 sheets of interdigitated fingers are placed in parallel, and the width of the inner 4 interdigitated fingers 0.1mm, interdigital length 3.415mm, interdigital spacing 0.1mm; sublateral 2 interdigital width 0.1mm, interdigital length 3.415mm, and inner interdigital spacing 0.2mm; installed on the sublateral 2 interdigital A pair of 5082-0012 PIN switches 4 from AVAGO Company (the power capacity is 1.5W at room temperature 25°C). The finger width is 0.3mm, the interdigit length is 0.5mm, and the interdigit distance is 0.2mm; one end of each interdigit is connected with 5 sidebands, the sideband width is 0.1mm, the sideband length is 2.1mm, and the input and output ports are 6 feeders They are respectively located in the center of the two interdigitated sidebands, and the width of the feeder line is 0.776mm. At the end of the outermost interfinger of the upper interfinger structure, it is connected to the ground wire of the lowest layer through two short-circuit nails 7 (solid cylindrical metal copper, radius 0.15mm, height 0.254mm). Both short-circuit nails pass through the dielectric layer vertically, and the projection of the short-circuit nails on the upper metal surface is a circle, which is tangent to the ends of the outermost two intersecting fingers that are not connected to the sideband, and is located in the intersecting fingers.

The electrical performance that can be realized by this specific implementation is: center frequency 9.5GHz, working bandwidth 2GHz, phase shift 22.5° (±1.5°) when a pair of switch states change at the same time, see Figure 10, Figure 11 and Figure 12.

Since this structure has 4 pairs of 8 interfingers in total, the current passing through the PIN switch on a single interfinger is only about 1/8 of the current passing through the entire phase shifter. After the power capacity test, it is found that the left-hand microstrip transmission line shifts the phase The power capacity of the switch can reach 12.8W, which is 8.53 times that of a single PIN switch.

Example 3:

Referring to Figure 13, Figure 14 and Figure 15, the left-hand microstrip transmission line phase shifter is designed on the PCB board, using Rogers RT/duroid 5880 dielectric substrate with a layer area of 8mm×6mm; the first and third layers of the PCB board are Conductor copper with a thickness of (0.004mm), the third layer of metal constitutes the ground 1 of the left-hand transmission line, the middle layer is a dielectric layer 2 with a dielectric constant of 2.2, and the thickness is 0.254mm; the center of the first layer of conductor copper is 3.915mm Make interdigitated capacitors 3 in an area of ×6.7mm, and the interdigit logarithm is 4, that is, each interdigit has 4 interdigits, and the two interdigitated interdigits are placed in parallel. The finger spacing is 0.1mm; the width of the second outer interdigital fingers is 0.1mm, the interdigital length is 3.415mm, and the distance from the inner interdigital fingers is 0.2mm; a pair of SKYWPRKS APD0810-000 PIN switches are installed on the second outer interdigital fingers 4 (the power capacity is 2.5W at room temperature 25°C), the switch position is 2.8mm away from the root of the fingers, the switch size is 0.35mm×0.35mm×0.127mm, the width of the two outermost fingers is 0.3mm, and the length of the fingers is 0.5mm , and the distance between the next inner intersecting fingers is 0.2mm; one end of each intersecting finger is connected with a sideband 5, the width of the sideband is 0.1mm, and the length of the sideband is 4.5mm. For the APD0810-000 PIN switch of SKYWPRKS Company 4; the input and output ports 6 feeders are respectively located at 0.762mm from the end where the sideband intersects with the intersecting fingers, and the width of the feeder is 0.776mm. At the end of the outermost interfinger of the upper interdigitation structure, it is connected to the ground wire of the lowest layer through two short-circuit nails 7 (solid cylindrical metal copper, radius 0.15mm, height 0.254mm). Both short-circuit nails pass through the dielectric layer vertically, and the projection of the short-circuit nail on the upper metal surface is a circle, which is tangent to the ends of the outermost two intersecting fingers that are not connected to the sideband, and is located in the intersecting fingers.

The electrical performance that can be realized by this specific implementation is: center frequency 8.75GHz, working bandwidth 1GHz, phase shift 45° (±0.5°) when two pairs of switch states change at the same time, see Figure 16, Figure 17 and Figure 18.

Since this structure has 4 pairs of 8 interfingers in total, the current passing through the PIN switch on a single interfinger is only about 1/8 of the current passing through the entire phase shifter, and the current passing through the PIN switch on the sideband is also small. Through the power capacity test, it is found that the power capacity of the left-hand microstrip transmission line phase shifter can reach 14.3W, which is 5.72 times of the power capacity of a single PIN switch.

Claims (3)

1. A microwave phase shifter based on a planar left-handed microstrip transmission line structure, including a planar left-handed microstrip transmission line unit, which is a printed circuit board (PCB), the first and third layers of which are copper conductors, and the middle layer is The dielectric plate with a dielectric constant of 1.07-13.6 has a planar metal microstrip interdigitated structure on the first layer to form an interdigitated capacitor. There are a pair of sidebands perpendicular to the interdigitated fingers at both ends of the interdigitated capacitor. The third layer of conductor Copper constitutes the ground of the left-hand microstrip transmission line. Select at least one sideband or any finger on the first layer, and use the via technology to connect the finger or sideband to the metal ground of the third layer of the PCB board through a short-circuit nail. constitutes an inductance characterized by: A pair of positively doped/intrinsic/negatively doped diode (PIN) switches are arranged at the centrally symmetrical positions of a pair of interfingers at symmetrical positions or at the centrally symmetrical positions of a pair of sidebands; the signal input and output ports are respectively located at The symmetrical position of a pair of side bands. 2. The microwave phase shifter for planar left-handed microstrip transmission lines according to claim 1, characterized in that: a pair of positively doped / Intrinsic/Negatively Doped Diode (PIN) Switch. 3. The microwave phase shifter for planar left-handed microstrip transmission line according to claim 1, characterized in that: a pair of positive doping/intrinsic/negative doping is set at the central symmetrical position of a pair of sidebands Diode (PIN) switch.

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