JP6478397B2 - Phased array antenna - Google Patents

Description

  The present invention relates to a phased array antenna device used in a microwave / millimeter wave band, and more specifically, a plurality of antenna elements arranged in an array for receiving radio waves from a transmitting antenna, and connected to each antenna element. The phase of the radio wave received by each antenna element is controlled by the individual phase shifter, so that the entire antenna surface is not set accurately in the direction of arrival of the high-frequency beam. The present invention relates to a phased array antenna technology capable of obtaining a high directivity gain.

  Conventionally, phased array antennas have been used in radar devices, mobile phone base stations, and the like. This not only changes the directivity of the entire antenna by adjusting the phase of the high-frequency signal transmitted and received by each antenna element, respectively, but also increases the gain in the direction of arrival of the desired radio wave, The processing for reducing the gain of radio waves coming from other directions can be performed electrically.

  The main basic components of the phased array antenna are an individual antenna element, a phase shifter that adjusts the phase of a high-frequency signal received by the individual antenna element, and a feed line. In addition, a phase detection circuit, a phase control circuit, and the like necessary for phase adjustment are indispensable circuits. However, a part relating to such a driving technique is omitted here, and elemental techniques of the above basic components will be described.

  The principle of operation of the basic components and the materials used vary depending on the purpose and mode of use of the antenna. Assuming transmission and reception of high-frequency radio waves in the 10 GHz band, patch antennas, dipole antennas, slot antennas, and the like can be used for individual antenna elements. For the phase shifter connected to each of these antenna elements, applications such as semiconductor elements, MEMS, and dielectric constant variable materials (ferroelectric materials, liquid crystals, etc.) can be cited as candidates. In addition, the power supply line may be a microstrip line, a coplanar line, a waveguide, or the like.

  In phased array antennas for satellite use, etc., because transmission and reception signals are high power, waveguides are used for phase shifters and feed lines, and the main materials including antenna elements are made of metal materials. Ceramics and the like have been used as some insulators. On the other hand, when the high-frequency signal is low power, a microstrip line or a coplanar line may be used as the feed line, and a patch antenna or a slot antenna having an antenna element on the extension thereof may be considered.

  The present invention relates to the latter low power phased array antenna. On these low power circuit boards, the back surface of a hard dielectric made of resin or ceramics is covered with a conductor such as copper foil to form a ground (GND) surface, and the surface is made of a highly conductive metal signal. There are many microstrip line types with lines and antenna elements attached, and usually a robust circuit board with a thickness of about 1 mm is used.

  Among the basic components of the phased array antenna, the performance as an antenna greatly depends on the mechanism, structure or material of the variable phase shifter. Here, the outline of the prior art will be described for the phase shifter for low power. A typical example of the microstrip line type variable phase shifter is a microstrip line length switching system. In this method, a plurality of microstrip lines having various electrical lengths (delay times) are mounted on a substrate, and the phase is varied by selecting them with a microwave switch. ing.

  A phase shifter using a hybrid coupler (also called 3dB Branch-Line Coupler) has been studied. FIG. 1 is a perspective view of the hybrid coupler. In a microstrip line structure in which a waveguide conductor 103 is laminated on a waveguide dielectric layer 102 on a waveguide ground conductor 101, a hybrid coupler 105 (within a dotted square) having an input line 104a and an output line 104b for high-frequency signals. ).

  The terminals at the four corners of the hybrid coupler 105 are A, B, C, and D terminals as shown in FIG. 1, and the open ends 106a and 106b having the same length are connected to a pair of terminals B and C, respectively. In the variable phase shifter to which the hybrid coupler of FIG. 1 is applied, a signal whose phase is delayed is output to the output line 104b due to the phase delay of the high-frequency signal by passing through the open-ended lines 106a and 106b.

  FIG. 2 shows a variable capacitor (varactor) 203a having the same characteristics between the open ends of the open ends 202a and 202b connected to the terminals B and C of the hybrid coupler 201 and the ground (GND) for the delay operation. , 203b are inserted, and a plan view of a variable phase shifter that delays the phase of the electromagnetic wave by a capacitance change due to a depletion layer under a reverse bias is shown. The variable capacitors 203a and 203b have their junction capacitance varied by an external bias electric field, and the phase is delayed in accordance with the magnitude of the capacitance.

  FIG. 3 is a perspective view of a variable phase shifter using a variable dielectric constant dielectric only in the region 307 of the dielectric layer immediately below the open-end lines 306a and 306b. The variable dielectric constant dielectric is a material whose dielectric constant changes when an external voltage is applied, and forms a hybrid coupler 305 having input / output lines 304a and 304b as in FIG. The open-ended lines 306a and 306b of the same length connected to the terminals B and C are connected, and the variable dielectric constant dielectric 307 is used only for the dielectric layer 307 in the open-ended lines 306a and 306b.

As an example of the variable dielectric constant dielectric material, a liquid crystal or a ferroelectric material whose dielectric constant changes depending on an applied voltage can be considered. For example, when the orientation of the liquid crystal molecules changes due to the applied voltage, the dielectric constant for electromagnetic waves propagating through the microstrip line changes due to dielectric anisotropy. A phase delay φ based on a propagation delay when an electromagnetic wave propagates through a length L microstrip line is expressed by the following equation.
φ = 2πf · √ (εeff) · L / c
Where εeff is the effective dielectric constant of the variable dielectric constant dielectric layer, f is the frequency of the propagating electromagnetic wave, and c is the speed of light in vacuum.
The liquid crystal disclosed in Non-Patent Document 1 shown below utilizes the applied voltage dependence of εeff.

D. Dolfi, M.M. Labeyrie, P.M. Joffre and P.M. Huiqard, “Liquid crystal microwave phase shifter,” Electron. Lett. , Vol. 29, no. 10, pp. 926-927, 1999

  In this method, since the phase delay is proportional to the square root of the effective dielectric constant εeff, a material / mechanism that causes a large change in the dielectric constant is required. As the liquid crystal, nematic liquid crystal, cholesteric liquid crystal, smectic liquid crystal, large dielectric anisotropy, Alternatively, a mixed liquid crystal of these, or a mixture in which an inorganic material or an organic material is mixed with the liquid crystal in order to improve voltage response can be considered.

  In the variable phase shifter configured as shown in FIG. 3, the high-frequency signal input from the input line 304a is output to the two open-ended lines 306a and 306b on the variable dielectric constant dielectric through the hybrid coupler 305, and two variable The electromagnetic waves reflected by the open ends of the dielectric constant dielectric tip open lines 306a and 306b are subjected to a propagation phase delay reflecting the bias voltage applied to the liquid crystal layer, and are re-input to the hybrid coupler 305 and pass through the hybrid coupler 305. The electromagnetic waves are combined and output to the output line 304b.

  An object of the present invention is to provide a flexible phased array antenna that is easy to carry anywhere, in a high-frequency range of 10 GHz band, and that is thin, lightweight, flexible, rounded and folded, and can be carried anywhere. It is to provide a variable phase shifter technology necessary for realizing an antenna.

  From the viewpoint of the object of the above invention, problems of the variable phase shifter technology using the microstrip line so far will be described. For example, both a system in which a plurality of microstrip lines having different lengths are mounted for each individual antenna element such as a patch antenna to change the phase shift, and a hybrid coupler type variable phase shifter are basically shown in FIG. As shown in FIG. 3, since a rigid substrate such as an alumina ceramic substrate, an alumina composite substrate, a sapphire substrate, or a glass epoxy substrate is used as a dielectric substrate, it can be applied only to a planar antenna. It cannot be a flexible and portable antenna.

  The microstrip line length switching system is a phase shifter provided with lines of electrical lengths of 22.5 °, 45 °, 90 °, and 180 °, and 360 / 22.5 = 16-tone digital (4 bits = 16 tone) variable. In this case, eight microwave switches are required. As the number of gradations increases, the number of necessary microwave switches increases, and the element space occupied by the mounted electrical length section increases, which prevents the antenna as a whole from being made compact.

  When a microwave PIN switch or a MESFET (metal-semiconductor field effect transistor) made of a compound semiconductor is used, there is a problem that insertion loss increases particularly in a high frequency range. On the contrary, when the electromagnetic mechanical type is used, the insertion loss can be reduced, but the volume occupied by the switch element is disadvantageous. Furthermore, such semiconductor switches and electromechanical switches cannot be made thin and flexible because they are made of silicon, compound semiconductors, inorganic insulating materials or metal materials.

  On the other hand, a MEMS (Micro Electro Mechanical Systems) system is also employed as a switch. Since this type of switch is also made of silicon or an inorganic insulating material, it cannot be made thin and flexible.

  When a variable capacitance diode (varactor) is used, it is used that the thickness of the depletion layer, that is, the capacitance changes with the magnitude of the applied voltage when a reverse bias is applied. The varactor itself is fabricated using a silicon device process and it is difficult to impart flexible characteristics. In addition, it is difficult to obtain a varactor having good capacity variable performance in a high frequency range.

  Next, the problem of the variable dielectric constant dielectric system will be described. The dielectric constant of a ferroelectric film or a liquid crystal film changes with the application of voltage. However, generally the change of the dielectric constant of a ferroelectric material due to the voltage is small, and usually a high voltage of several kV is required. On the other hand, the alignment polarization of liquid crystals occurs at a relatively low voltage, and so far there have been many research examples.

  One of the challenges to the application of liquid crystals to variable phase shifters is that the liquid crystal layer thickness needs to be large (˜100 μm) in order to produce a sufficient phase change, which increases the driving voltage. (~ 100V) In order to overcome this problem, various attempts have been made, such as the structure of the liquid crystal cell and the use of load electrodes, but no significant improvement has been observed.

  In addition, the liquid crystal device has a structure in which it is sandwiched between two electrodes, and changes the molecular orientation with the voltage applied between the electrodes, so it is necessary to keep the electrode spacing constant in order to obtain uniform molecular orientation. is there. For this reason, in order to make the liquid crystal layer flexible, a special structure that maintains a constant interval even when bent is required. For example, a display or the like may have a structure in which a side wall is provided between electrodes and curved to keep a constant interval. However, such a structure cannot be applied as a non-uniform dielectric layer for microwave propagation. It can be said that thinning and flexibility are difficult. Further, a technique for forming a uniform rubbing layer or a technique for uniformly injecting liquid crystal into a variable dielectric constant dielectric layer is required, but there is no prospect for these.

  The third problem of the liquid crystal type variable phase shifter that has been studied so far is that the insertion loss is large. As a result of analysis, it is said to be due to dielectric loss, but a new liquid crystal structure for this purpose is required.

None of the above-described problems of the current technology meet the purpose of the present invention. The present invention solves the above problems,
1) In the ultra high frequency region of 10 GHz band,
2) A flexible type that is thin and easy to carry.
3) Efficient phase shift with low insertion loss and power saving
4) It can be manufactured at low cost by a printing method that saves power and harmonizes with the environment.
A flexible phased array antenna having a variable phase shifter and a manufacturing method thereof are provided.

  The phased array antenna according to the present invention, which has been made to solve the above-mentioned problems, includes a dielectric layer made of a flexible and flexible organic material, a waveguide ground conductor made of a conductive material such as a flexible metal thin film, and the like. Combining a flexible conductive polymer actuator with a flexible flexible 90 ° hybrid coupler characterized by comprising a waveguide formed of a flexible metal thin film or the like on the organic dielectric layer, the 90 ° The basic configuration is to control the phase of the high-frequency signal input to the hybrid coupler.

  In this case, in the variable phase shifter, when the four corner terminals of the flexible 90 ° hybrid coupler are set to A, B, C, D in the clockwise direction, and a high frequency signal is input to the terminal A, the other pair of terminals B , C, the phase of the high-frequency signal output from the terminal D is adjusted according to the distance from the open end of the open end line to the ground point. A means for adjusting and changing is adopted.

Further, when grounding a predetermined position of the open-end line of the 90 ° hybrid coupler, a means for grounding by applying an external field such as voltage to the flexible and flexible conductive polymer actuator is preferably employed. be able to.
And the phase shift can be continuously varied by arranging the bending direction of the conductive polymer actuator parallel to the line on the open end line.

  On the other hand, in a preferred embodiment, when grounding a predetermined position of the open-ended line using a flexible conductive polymer actuator, the open-ended lines of the two ends are as close as possible without affecting the propagation of high-frequency signals. A configuration is adopted in which the same position of two open-ended lines is grounded simultaneously by a set of flexible conductive polymer actuator grounding mechanisms.

Then, by arranging the grounding mechanisms of a plurality of flexible conductive polymer actuators in the length direction of the open end line, and arranging the bending direction in a direction perpendicular to the open end line, it corresponds to the area occupied by each grounding mechanism. A flexible digital variable phase shifter having a resolution and a discrete variable phase shift function can be obtained.
Preferably, when the predetermined position of the open-ended line is grounded by the conductive polymer actuator, an actuator having a laminated structure in which an electrolyte layer is sandwiched between two electrode layers is used as the conductive polymer.

In this case, the electrode layer is mainly composed of a mixture of polyethylene dioxythiophene (PEDOT) and polystyrene sulfonic acid (PSS), and a vinylidene fluoride / hexafluoropropylene copolymer [P (VDF / HFP)] is added thereto. It is desirable to use a mixed solution as a raw material.
Desirably, a mixed solution of an ionic liquid and a vinylidene fluoride / hexafluoropropylene copolymer [P (VDF / HFP)] is used as the electrolyte layer.

  Preferably, the waveguide, the variable phase shifter, and the antenna element are manufactured by a printing method including bonding and coating methods, and a screen using silver paste, copper paste, or gold paste as the printing method in this case A printing method is preferably employed.

  The present invention provides an elemental technology that contributes to a flexible phased array antenna in the 12 GHz band and a manufacturing method thereof. First, it is based on a 90 ° hybrid coupler formed by a waveguide grounding conductor composed of a thin and flexible organic dielectric layer and a metal thin film, and a microstrip line composed of a waveguide conductor, and the phase shifter depends on the voltage of the polymer actuator. Since the deformation function is used, it is possible to provide a variable phase shifter for a flexible phased array antenna that is thin, flexible, and portable.

  Since the phase shifter increases or decreases the length of the high-frequency traveling line by grounding a predetermined position of the open-ended line, it is basically a reflection type and has a small insertion loss. Further, it can be formed more compactly than a line length switching method in which a large number of waveguides having different line lengths are arranged for each antenna element. The occupied area on the substrate surface is small. The present invention can be designed as an analog system or as a digital modulation system.

  For example, a structure in which the patch antenna element and the variable phase shifter of the present invention are combined can be manufactured by a printing method including pasting and coating. Therefore, it can be made a disposal at a low price.

It is a perspective view of the conventional hybrid coupler using a microstrip line. It is a basic block diagram of the conventional variable phase shifter using a variable capacitor (varactor). It is a perspective view of the conventional variable phase shifter using a variable dielectric constant dielectric. It is a basic principle figure which shows the 90 degree hybrid coupler which makes the basis of the variable phase shifter of this invention, and the grounding structure of an open line. The polymer actuator utilized in this invention is shown, (a) is a basic structure figure, (b) shows the state which applied the voltage between both electrode layers. It is a basic principle figure which shows the analog type phase-shifting variable means using a curved polymer actuator, (a) is a top view, (b) is a longitudinal cross-sectional view. The structure of the hybrid coupler for open line proximity type phase shifters and the open end line | wire is shown, (a) is a top view, (b) is XX 'sectional drawing of (a). It is the characteristic view which showed the relationship between the voltage applied to a polymer actuator, and a phase. It is a perspective view of a flexible antenna unit using a curved polymer actuator. 1 shows a flexible phased array antenna unit adopting a digital phase variable system, where (a) is a top view, (b) is a sectional view taken along line XX ′ of (a), and (c) is X when an actuator is operated. It is -X 'sectional drawing.

  The phase shifter shown in FIG. 2 and FIG. 3 described above includes a variable capacitance diode between the open end of the open-ended line connected to the pair of terminals B and C of the 90 ° hybrid coupler and the ground (GND). The phase of a high-frequency signal traveling through the open-ended line is delayed depending on whether the capacitance is inserted and the dielectric constant of the dielectric layer immediately below the open-ended line is varied by applying an external electric field.

On the other hand, the variable phase shifter employed in the phased array antenna according to the present invention receives a high-frequency signal from the input terminal A of the hybrid coupler 405 as shown in FIG. By connecting a predetermined position (XX ′) of the two open-ended lines 406a and 406b connected to the ground to the ground (GND) using a flexible soft actuator, the transition corresponding to the predetermined position is performed. It is characterized by trying to adjust the phase amount.
The present invention has been conceived of utilizing a polymer actuator that can be manufactured at a relatively low cost by the printing method as the variable electrical length switch and can realize a flexible function.

In the 90 ° hybrid coupler 405 of FIG. 4, four 90 ° phase delay lines 404a, 404b, 404c, and 404d having an electrical length of λ / 4 (λ: wavelength of an electromagnetic wave in a dielectric layer) surround a rectangle. Are arranged as follows.
Here, the four corner terminals of the 90 ° hybrid coupler 405 are labeled A, B, C, and D in the clockwise direction. Open-ended lines 406a and 406b are connected to the terminals B and C in the same manner as in FIGS. 2 and 3 described above.

  When a high frequency signal is input to terminal A, the signal arrives at terminal B with a phase delay of 90 °. The signal at the terminal B travels through the open end line 406a, is reflected at the open end 408a, and returns to the hybrid coupler 405. The terminal C reaches the terminal B with the phase of the signal from the terminal B delayed by 90 °. Similarly, the signal at the terminal C travels along the open end line 406b, is reflected at the open end 408b, and returns to the hybrid coupler. These reflected waves are also delayed by 90 ° in phase and reach the terminal D for output.

The impedance of each delay line 404a, 404b, 404c, 404d is Zp (404b, 404d) so that the power of the signal input to the terminal A in FIG. ), Zr (404a, 404c).
In the 90 ° hybrid coupler, Zp = Z ₀ and Zr = Z ₀ / √2. Here, Z ₀ is the characteristic impedance of the microstrip line.

In FIG. 4, the phase of the signal output from the terminal D can be adjusted by grounding a predetermined position of the open-ended line. Since the ground point is a high-frequency signal reflection point, the amount of phase shift depends on the distance (L) between the ground points 407a and 407b and the respective open ends 408a and 408b. That is, when the ground points 407a and 407b are shifted to the terminal B or terminal C side by a distance L from the open ends 408a and 408b, the signal reflected at the ground point is φ = 2 ( L / λ) · (2π)
Only the phase will be advanced. This movement of the ground point corresponds to the increase / decrease of the waveguide length.

  The movement of the ground contact points 407a and 407b of the open-ended line with a soft actuator will be described. As for the movement of the grounding point, a system in which the open-end lines 406a and 406b are mechanically extended and contracted has been proposed, but it does not meet the requirement of thinness and flexibility for the purpose of the present invention. On the other hand, the present invention has a feature that a polymer actuator using a flexible organic material can be made thin and flexible, and can be manufactured by a printing method that is power-saving and harmonized with the environment.

  FIG. 5 shows an example of the basic structure of the polymer actuator used in the present invention. As shown in FIG. 5A, an electrolyte layer 502 is sandwiched between electrode layers 501a and 501b. For example, as described in International Publication No. WO2009 / 150697, when a voltage is applied between both electrode layers of this film, bending occurs as shown in FIG.

  As shown in FIG. 6, the present invention is combined with the open-end line of the 90 ° hybrid coupler shown in FIG. 2 as a contact switch for the open-end line of the polymer actuator having the basic structure shown in FIG. It features a mechanism that moves the grounding point of the open-ended line according to the degree.

A mechanism capable of continuously varying the amount of phase shift will be described.
A sectional view of the open-ended line portion is shown in FIG. A grounding conductor 609 is provided between the two open-ended lines 603a and 603b. The grounding conductor 609 is connected to a grounding via hole 610 in which a conductor such as a metal is embedded from the waveguide grounding conductor 601 and has the same potential (earth). The curved type polymer actuator 605 is arranged on the open end line so that the bending direction coincides with the open end line direction. A grounding conductor thin film 604 is attached to the lower part of the polymer actuator 605. When this grounding conductor thin film 604 comes into contact with the open-end lines 603a and 603b and the grounding conductor 609, the grounding point is grounded. [Point X in FIG. 6B]. It is also conceivable to insert a thin insulating layer between the grounding conductor 604 and the polymer actuator 605 to electrically insulate the polymer actuator drive power supply system from the microwave waveguide.

  When a voltage is applied to the polymer actuator 605 through the actuator electrodes 606 and 607, the magnitude of the curvature changes depending on the magnitude of the applied voltage. That is, when the applied voltage is large, the curve is large and the ground point X moves toward the open end, and when the applied voltage is small, the ground point X moves toward the 90 ° hybrid coupler. These movements are continuous, and the amount of phase shift can be continuously changed.

Since the phase shift amount is represented by φ = 2 (L / λ) · (2π), if L = (1/2) λ, then φ = 2π, the length of the curved polymer actuator, That is, the maximum moving distance of the grounding point may be set to L = (1/2) λ.
In FIG. 6, reference numeral 602 denotes a waveguide dielectric layer, and 608 denotes an insulating spacer.

[Example 1]
[Production of 90 ° hybrid coupler and variable phase shifter by printing method]
One of the objects of the present invention is to realize a manufacturing technique based on a printing method that saves power and is harmonized with the environment. For a flexible 90 ° hybrid coupler that is the base of a variable phase shifter or flexible phased array antenna, the waveguide dielectric layer 102 is a thin and flexible organic dielectric film in FIG. The waveguide installation conductor 101 and the waveguide conductor 103 are produced by a printing method using conductive ink. It is also conceivable to attach a highly conductive metal thin film such as a copper foil having a predetermined thickness.

  As a flexible organic dielectric film, PEN (polyethylene naphthalate), PET (polyethylene terephthalate) film, etc. can be considered. The relative dielectric constant of these materials is stable to about -3.0 from the low frequency band to the high frequency range of 10 GHz band, and is suitable as an insulating material for microstop lines of antennas and phase shifters. Furthermore, a film with a small Tan δ, such as Teflon (registered trademark), is desirable for reducing insertion loss.

  A microstrip line, that is, a 90 ° hybrid coupler circuit is formed on the surface of the organic dielectric film by a printing method using silver paste or the like. Possible printing methods include screen printing, gravure printing, offset printing, and ink-jet method, but a thick film waveguide of several μm or more is required from signal transmission in the high frequency band, so a highly viscous silver paste was used. A screen printing method is suitable.

In the circuit of FIG. 7, the open-ended lines 706a and 706b are compared to FIGS. 2 and 3 in order to make it easy to ground the positions at the same distance from the open ends of the two open-ended lines 406a and 406b of FIG. In close proximity. However, a minimum interval Y that does not cause a loss of propagation of a high-frequency signal due to an interaction or the like or cause a phase shift abnormality is ensured. With this arrangement, the desired positions of the two open-ended lines can be installed simultaneously with a set of grounding mechanisms (FIG. 6).
7, reference numeral 701 denotes a waveguide ground conductor, 702 denotes a waveguide dielectric layer, 703 denotes a waveguide conductor, 704a and 704b denote input / output lines, and 705 denotes a hybrid coupler. The same reference numerals are used for the parts already described with reference to FIG. 1, and the same function is achieved.

[Production of polymer actuator]
Next, the polymer actuator having the function of the present invention will be described. As shown in FIG. 5, the polymer actuator has a laminated structure of a pair of electrode layers 501a and 501b and an electrolyte layer 502 sandwiched between the electrode layers. A method for producing this type of polymer actuator is described in the above-mentioned International Publication No. WO2009 / 150697.

(Formation of electrode layer)
As an example of forming an electrode layer, a main component is a mixture of polyethylene dioxythiophene (PEDOT) and polystyrene sulfonic acid (PSS) (product name: Clevios PH500, manufactured by Heraeus Co., Ltd.), and this is vinylidene fluoride / hexafluoropropylene. A solution in which a small amount of a copolymer [P (VDF / HFP)] (Arkema, trade name: Kynar2801-00) was mixed was applied on a glass substrate and dried. After drying, annealing is performed at 70 ° C. for 1 hour.

(Formation of electrolyte layer)
The electrolyte layer consists of an ionic liquid (1-ethyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide) (manufactured by Aldrich) and a vinylidene fluoride / hexafluoropropylene copolymer [P (VDF / HFP)] (Arkema (Product name: Kynar2801-00) manufactured by the company was annealed at 100 ° C. for 30 minutes. Other materials can be considered for the ionic liquid.

[Production of laminated actuator]
The electrolyte layer was sandwiched between the two electrode layers and annealed at 110 ° C. for 30 minutes to be laminated. This laminated film was cut into a size that can ground the two open-ended lines in FIG. 2 to obtain a polymer actuator.

  FIG. 8 shows the relationship between the applied voltage and the phase of the polymer actuator in the variable phase shifter in which the 90 ° hybrid coupler produced by the screen printing method using silver paste and the polymer actuator are combined as shown in FIG. Indicates. The phase increased by about 30 ° C. as the actuator voltage increased from 3 V to 6 V, demonstrating the function of the present invention.

  The operation (curving) principle of the polymer actuator of the present invention is considered to be based on the size difference between the cation and anion of the ionic liquid, but the details are unknown.

[Example 2]
A discrete phase control method (digital phase shifter) is also conceivable in which a grounding point on the open-ended line is determined and grounded using a polymer actuator array acting on each grounding point. FIG. 9 shows an example, and the discrete resolution is determined by the actuator mechanism size Z such as the actuator and matrix drive electrode line width. In FIG. 9, reference numeral 901 is a waveguide ground conductor, 902 is a waveguide dielectric layer, 903 is a metal conductor buried via hole, 904a and 904b are open-ended lines, 905 is a ground pad, 906 is a ground polymer actuator, 907 Is an insulating thin film, 908 is a grounding conductive thin film, 909 is an actuator driving lower electrode, and 910 is an actuator driving upper electrode.

[Example 3]
FIG. 10 is a perspective view of a flexible phased array antenna unit in which the 90 ° hybrid coupler of FIG. 7, the analog variable phase shifter of FIG. 6, and the patch antenna element are combined. The high-frequency signal received by the patch antenna element 1003 is input to the input end 1005a of the 90 ° hybrid coupler 1004 and output to the output end 1005b with a phase corresponding to the ground position of the conductive polymer actuator 1006. Grounding is performed by bringing the ground pad 1007 into contact with the two open-ended lines via the buried via hole 1008. The conductive polymer actuator 1006 is bent by applying a voltage to the conductive polymer actuator electrode wires 1009a and 1009b. The flexible phased array antenna is configured by arraying a plurality of the flexible phased array antenna units.

  As described above, according to the present invention, the phased array antenna can be made thin, light, and flexible, and can be easily carried by being rolled or folded. This can contribute to mobile reception such as satellite broadcasting. In addition, it is possible to provide a phased array antenna that can reduce insertion loss as much as possible, maintain little directivity gain even during beam tilt, and maintain high directivity gain, and is useful as an in-vehicle radar, satellite communication antenna, millimeter wave sensor, etc. is there.

101: Grounding conductor for waveguide, 102: Dielectric layer for waveguide, 103: Conductor for waveguide, 104a: Input end, 104b: Output end, 105: 90 ° hybrid coupler, 106a: Open end line, 106b: End Open line, 201: hybrid coupler, 202a, 202b: open end line, 203a, 203b: variable capacitance diode (varactor), 304a: input end, 304b: output end, 305: hybrid coupler, 306a: open end line, 306b: Open end line, 307: Variable dielectric constant dielectric, 404a, 404b, 404c, 404d: 90 ° delay line, 405: Hybrid coupler, 406a, 406b: Open end line, 407a, 407b: Ground point, 408a, 408b: Open End, 501a, 501b: electrode layer, 502: electrolyte layer, 60 : Ground conductor for waveguide, 602: Dielectric layer for waveguide, 603a, 603b: Open end line, 604: Conductive thin film for ground, 605: Polymer actuator for ground, 606: Lower electrode for actuator, 607: Upper part for actuator Electrode, 608: Insulating spacer, 609: Grounding conductor, 610: Grounding via hole, 701: Grounding conductor for waveguide, 702: Dielectric layer for waveguide, 703: Conductor for waveguide, 704a, 704b: Input / output line 705: Hybrid coupler, 706a, 706b: open-ended line, 901: ground conductor for waveguide, 902: dielectric layer for waveguide, 903: via hole embedded with metal conductor, 904a, 904b: open-ended line, 905: ground pad 906: conductive polymer actuator for grounding, 907: insulating thin film, 908: for grounding Electrode thin film, 909: lower electrode for driving actuator, 910, upper electrode for driving actuator, 1001: conductor for grounding, 1002: dielectric layer for waveguide, 1003: patch antenna element, 1004: 90 ° hybrid coupler, 1005a: input End, 1005b: Output end, 1006: Conductive polymer actuator, 1007: Ground pad, 1008: Via hole embedded in metal conductor, 1009a, 1009b: Electrode wire for conductive polymer actuator

Claims (11)

  Consists of a dielectric layer made of a flexible and flexible organic material, a grounding conductor for a waveguide made of a conductive material such as a flexible metal thin film, and a waveguide formed of a flexible metal thin film on the organic dielectric layer. Flexible and flexible 90 ° hybrid coupler combined with a flexible conductive polymer actuator to control the phase of a high-frequency signal input to the 90 ° hybrid coupler Phased array antenna with phase shifter.   In the variable phase shifter, when the four corner terminals of the flexible 90 ° hybrid coupler are set to A, B, C, and D in the clockwise direction, and a high frequency signal is input to the terminal A, the other pair of terminals B and C are connected to each other. By grounding a predetermined position of the two connected open end lines, the phase of the high-frequency signal output from the terminal D is adjusted and changed according to the distance from the open end of the open end line to the ground point. A phased array antenna comprising the flexible variable phase shifter according to claim 1.   2. The grounding is performed by applying an external field such as a voltage to a flexible and flexible conductive polymer actuator and deforming the ground at a predetermined position of the open end line of the 90 ° hybrid coupler. Or a phased array antenna comprising the flexible variable phase shifter according to 2;   The flexible analog variable shift according to any one of claims 1 to 3, wherein the phase shift is continuously variable by arranging the bending direction of the conductive polymer actuator parallel to the line on the open-ended line. Phased array antenna with phaser   When grounding a predetermined position of the open-ended line using a flexible conductive polymer actuator, two open-ended lines are arranged as close as possible without affecting the propagation of high-frequency signals, and a set of 5. The phased array antenna having a flexible variable phase shifter according to claim 1, wherein the same position of the two open-ended lines is grounded simultaneously by a flexible conductive polymer actuator grounding mechanism. .   By arranging the grounding mechanisms of a plurality of flexible conductive polymer actuators in the length direction of the open-ended line and arranging the bending direction in a direction perpendicular to the open-ended line, the resolution corresponding to the area occupied by each grounded mechanism The phased array antenna having a flexible digital variable phase shifter according to claim 2, wherein the phased array antenna has a discrete variable phase shift function.   3. An actuator having a laminated structure in which an electrolyte layer is sandwiched between two electrode layers is used as a conductive polymer for grounding a predetermined position of the open end line with a conductive polymer actuator. A phased array antenna comprising the flexible variable phase shifter according to any one of items 1 to 6.   The electrode layer was mainly composed of a mixture of polyethylene dioxythiophene (PEDOT) and polystyrene sulfonic acid (PSS), and a vinylidene fluoride / hexafluoropropylene copolymer [P (VDF / HFP)] was mixed therewith. The phased array antenna having a flexible variable phase shifter according to claim 7, wherein the solution is a raw material.   The flexible variable phase shifter according to claim 7 or 8, wherein a mixed solution of an ionic liquid and a vinylidene fluoride / hexafluoropropylene copolymer [P (VDF / HFP)] is used as the electrolyte layer. Phased array antenna provided.   The phased array antenna according to any one of claims 1 to 9, wherein the waveguide, the variable phase shifter, and the antenna element are manufactured by a printing method including bonding and a coating method.   The phased array antenna according to claim 10, wherein a screen printing method using a silver paste, a copper paste, or a gold paste is used as the printing method.

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