JP2006067403A - Stacked aperture antenna - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thin stacked aperture antenna by which a feeding line is constituted without increasing the thickness of a dielectric substrate in a high band layered aperture antenna. <P>SOLUTION: The stacked aperture antenna is equipped with a high frequency line 8 constituted of a line conductor 6 formed on the upper surface of a dielectric layer 1 and an identical surface grounding conductor layer 2 formed so as to surround one end part 7 of the line conductor 6, a slot 3 formed on the identical surface grounding conductor layer 2 so as to perpendicularly cross the line conductor 6 and a plurality of shield penetration conductors 4 formed inside the dielectric layer 1 so as to surround the slot 3. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an antenna used for communication and radar using microwaves and millimeter waves, and relates to a laminated aperture antenna that has a wide band and can be thinned.

  A horn antenna using a waveguide is known as an antenna that efficiently radiates electromagnetic waves such as microwaves and millimeter waves. A horn antenna is an antenna that radiates a high-frequency signal transmitted through a waveguide into space. The inside of the waveguide has the same dielectric constant as that of space (generally, the dielectric constant of air), and its impedance is close to that of space. The electromagnetic field mode of the high-frequency signal transmitted through the waveguide is similar to the electromagnetic field mode of the high-frequency signal transmitted through the space. The electromagnetic field mode of the high-frequency signal transmitted through the waveguide can be easily It can change to the electromagnetic field mode of the high-frequency signal to be transmitted. For these reasons, it is known that the horn antenna has low reflection due to impedance and mode mismatch, and is highly efficient and relatively wide in bandwidth.

  On the other hand, circuits generally used for communication and radar using microwaves and millimeter waves are planar circuits using microstrip lines and coplanar lines. In this case, in order to connect the circuit and the horn antenna, a converter for converting the planar circuit into the waveguide is required, and the use of the converter may cause an increase in cost and performance degradation such as reflection. A patch antenna is known as one of antennas that directly radiate electromagnetic waves from a planar circuit into space. In the patch antenna, a planar circuit having a relatively small impedance and a space having a relatively large impedance are matched using the resonance of the patch. In matching by resonance, the impedance of the resonator affects the band. In order to increase the impedance of the patch in order to widen the band, it is necessary to reduce the patch width, and the radiation efficiency decreases. Increasing the patch width to increase the radiation efficiency tends to reduce the patch impedance and narrow the band. In the design of a patch antenna, the first condition is to efficiently radiate a high-frequency signal into the space. Therefore, the band is often narrowed at the expense of the band.

In order to solve this problem, a laminated aperture antenna using a cavity resonator having a large impedance as a resonator has been proposed. In this laminated aperture antenna, a cavity resonator in which a dielectric is filled inside a dielectric substrate forming a planar circuit is configured to realize a broadband antenna.
JP 2001-016027 A

  However, in the multilayer aperture antenna, since the cavity resonator needs to be formed inside the dielectric substrate, the dielectric substrate may be thicker than the patch antenna. In particular, when a feed line such as a laminated waveguide or a microstrip line is used to feed the slot which is the primary radiator of this antenna, a dielectric layer is further provided on the slot to form the feed line. Therefore, there is a problem that the thickness of the dielectric substrate is further thicker than the thickness of the cavity resonator and the size of the device is increased.

  Accordingly, the present invention has been completed in view of the above-described conventional problems, and an object of the present invention is to configure a feeder line without increasing the thickness of a dielectric substrate in a high-band multilayer aperture antenna. An object of the present invention is to provide a thin laminated aperture antenna that can be used.

  The laminated aperture antenna of the present invention includes a line conductor formed on an upper surface of a dielectric layer, a high-frequency line including a coplanar ground conductor layer formed so as to surround one end of the line conductor, and the coplanar grounding. The conductor layer includes a slot formed so as to be orthogonal to the line conductor, and a plurality of shield penetrating conductors formed inside the dielectric layer so as to surround the slot.

  In the laminated aperture antenna of the present invention, preferably, the dielectric ground layer has an opening larger than the slot and the shield ground layer provided so as to face the slot, and in plan view, the shield ground layer. A plurality of connection through conductors that electrically connect the shield ground layer and the same-surface ground conductor layer are formed so as to surround the opening along the opening.

  In the multilayer aperture antenna according to the present invention, preferably, the distance between the one end of the line conductor and the center of the slot is (2n-1) of the wavelength of the high-frequency signal transmitted through the high-frequency line. ) / 4 times (n is a natural number).

  In the multilayer aperture antenna according to the present invention, preferably, the line conductor is a short-circuited end whose one end is electrically connected to the coplanar ground conductor layer.

  In the multilayer aperture antenna according to the present invention, preferably, the distance between the short-circuited end and the center of the slot is 1/2 of the slot width or n / 2 times the wavelength of the high-frequency signal (n is a natural number). It is characterized by being.

  In the multilayer aperture antenna according to the present invention, preferably, the interval between the plurality of shield through conductors is not more than ¼ times the wavelength of the high-frequency signal in the dielectric layer.

  The laminated aperture antenna of the present invention preferably includes an upper dielectric layer formed on the upper surface of the dielectric layer and an upper ground conductor layer formed on the upper surface of the upper dielectric layer. It is characterized by that.

  The laminated aperture antenna of the present invention includes a line conductor formed on the upper surface of a dielectric layer and a high-frequency line composed of the same-surface ground conductor layer formed so as to surround one end of the line conductor, and the same-surface ground conductor layer And a plurality of shield penetrating conductors formed inside the dielectric layer so as to surround the slot, so that the high-frequency line and the slot are electromagnetically coupled to each other. Therefore, the feeder line can be configured without increasing the thickness of the dielectric substrate, and a thin laminated aperture antenna can be provided.

  The laminated aperture antenna of the present invention preferably has a shield ground layer provided inside the dielectric layer with an opening larger than the slot and facing the slot, and an opening along the opening in plan view. And a plurality of connecting through conductors that electrically connect the shield grounding layer and the same-surface grounding conductor layer so as to surround the matching layer, and are formed by the dielectric layer and the shield through conductor. Provided a laminated aperture antenna with stable performance, with the outer periphery of the filter and the high-frequency line electrically isolated, and unnecessary resonance that is easily excited at the outer periphery of the matching unit is not excited in the electromagnetic wave mode of the high-frequency line. it can.

  In the multilayer aperture antenna of the present invention, preferably, the distance between the one end of the line conductor and the center of the slot is (2n−1) / 4 of the wavelength of the high-frequency signal transmitted through the high-frequency line. For example, when n is 1, the distance between one end of the line conductor and the center of the slot is 1/4 times the wavelength of the high-frequency signal. Since one end of the line conductor is now open, the current at one end becomes 0, and the current in the line conductor becomes maximum at a position that is 1/4 times the wavelength of the high-frequency signal from one end, that is, at the center of the slot. The slot can be efficiently excited by the magnetic field generated by the above, and as a result, a laminated aperture antenna with good radiation efficiency can be provided. When n is 2, the distance between the one end and the center of the slot is 3/4 times the wavelength of the high-frequency signal, and the current of the line conductor is maximized at the center of the slot as in the case where n is 1. A laminated aperture antenna with good radiation efficiency can be provided. Similarly, when n is a natural number of 3 or more, the current of the line conductor is maximized at the center of the slot, and a laminated aperture antenna with good radiation efficiency can be provided.

  In the multilayer aperture antenna of the present invention, preferably, the line conductor is a short-circuited end having one end electrically connected to the same-surface grounded conductor layer, so that the current at the short-circuited end is maximum and the short-circuited end. A standing wave that repeats the current 0 and the current maximum is generated every time the wavelength of the high frequency signal is 1/4 times away from the slot, and the slot can be efficiently excited by the magnetic field generated by the standing wave, resulting in good radiation efficiency. A stacked aperture antenna can be provided.

  In the laminated aperture antenna according to the present invention, preferably, the distance between the short-circuited end and the center of the slot is 1/2 the slot width or n / 2 times the wavelength of the high-frequency signal (n is a natural number). The distance between the short-circuit end and the center of the slot is 1/2 times the wavelength of the high-frequency signal (n = 1), 1 time (n = 2),... The current of the conductor is maximized, and the slot can be efficiently excited by the magnetic field generated by the current. As a result, it is possible to provide a laminated aperture antenna with good radiation efficiency.

  In the multilayer aperture antenna of the present invention, preferably, the distance between the plurality of shield through conductors is not more than ¼ times the wavelength of the high frequency signal inside the dielectric layer, so It is possible to provide a laminated aperture antenna that suppresses leakage of electromagnetic waves and has high radiation efficiency.

  The laminated aperture antenna of the present invention preferably includes an upper dielectric layer formed on the upper surface of the dielectric layer, and an upper ground conductor layer formed on the upper surface of the upper dielectric layer. It is possible to provide a multilayer aperture antenna having high radiation efficiency by suppressing leakage of electromagnetic waves from the slot to the upper side.

  The multilayer aperture antenna of the present invention will be described in detail with reference to the drawings. 1A and 1B are schematic views for explaining an example of a laminated aperture antenna according to the present invention. FIG. 1A is a top view and FIG. 1B is a cross-sectional view taken along line A-AA.

  In FIG. 1, 1 is a dielectric layer, 2 is a coplanar ground conductor layer, 3 is a slot, 4 is a shield through conductor, 5 is a conductor non-formation region, 6 is a line conductor, 7 is one end, 8 is a high-frequency line, G is a gap, and LO is an open end length.

  In the example of the laminated aperture antenna of the present invention, the dielectric layer 1, the same-surface ground conductor layer 2 disposed on the upper surface of the dielectric layer 1, the slot 3 formed in the same-surface ground conductor layer 2, A plurality of shield through conductors 4 are arranged in the dielectric layer 1 with a predetermined gap so as to surround the slot 3 to constitute a laminated aperture antenna. Then, a conductor non-formation region 5 is formed in the same plane ground conductor layer 2 so as to be orthogonal to the slot 3, and a line conductor 6 having one end 7 is arranged inside the conductor non-formation region 5, thereby providing the same plane ground conductor layer 2. And the line conductor 6 are configured, and the high frequency line 8 and the slot 3 are electromagnetically coupled to each other so that a feed line can be configured without increasing the thickness of the dielectric layer 1. A stacked aperture antenna can be provided. In this example, the electromagnetic coupling between the high frequency line 8 and the slot 3 is realized by the electromagnetic coupling between the open end of the high frequency line 8 and the slot 3 because the one end 7 is an open end.

  In the electromagnetic coupling between the open end of the high-frequency line 8 and the slot 3, the open end length LO, which is the distance between the one end 7 and the center of the slot 3, is set to (2n-1) / 4 times the wavelength of the high-frequency signal (n Is a natural number), for example, when n is 1, the open end length LO is 1/4 times the wavelength of the high-frequency signal. Since the one end 7 of the line conductor 6 is now open, the current at the one end 7 is 0, and the current in the line conductor 6 is maximized at a position that is 1/4 times the wavelength of the high-frequency signal from the one end 7, that is, at the center of the slot 3. Thus, the slot 3 can be efficiently excited by the magnetic field generated by the current of the line conductor 6, and as a result, a laminated aperture antenna with good radiation efficiency can be provided. When n is 2, the open end length LO is 3/4 times the wavelength of the high-frequency signal, and when n is 1, the current of the line conductor 6 is maximized at the center of the slot 3 and the radiation efficiency is good. A stacked aperture antenna can be provided.

  Further, when the gap G between the shield through conductors 4 is set to ¼ times the wavelength of the high-frequency signal in the dielectric layer 1, the leakage of electromagnetic waves from the gap between the shield through conductors 4 is suppressed, and the radiation efficiency is improved. A mold aperture antenna can be provided.

  2A and 2B are schematic views for explaining another example of the laminated aperture antenna of the present invention, wherein FIG. 2A is a top view and FIG. 2B is a B-BB sectional view.

  2, the same parts as those in FIG. 1 are denoted by the same reference numerals as those in FIG. 1, and LS is the short-circuit end length.

  The example of the laminated aperture antenna of the present invention is different from the example of FIG. 1 in that only one end 7 of the line conductor 6 is electrically connected to the same plane ground conductor layer 2 and the other parts are the same. is there. Therefore, as in the example of FIG. 1, the feed line can be configured without increasing the thickness of the dielectric layer 1, and a thin laminated aperture antenna can be provided. In this example, the electromagnetic coupling between the high-frequency line 8 and the slot 3 is realized by the electromagnetic coupling between the short-circuited end of the high-frequency line 8 and the slot 3 because the one end 7 is a short-circuited end. In this case, a standing wave is generated that repeats current 0 and current maximum every time the short-circuited end has a maximum current and is 1/4 times the wavelength of the high-frequency signal from the short-circuited end. As a result, a laminated aperture antenna with good radiation efficiency can be provided.

  In this case, if the short-circuit end length LS is halved of the slot width, the current at the short-circuit end is maximized, and the maximum magnetic field is generated by the maximum current in the slot, so that the slot can be excited efficiently. As a result, a laminated aperture antenna with good radiation efficiency can be provided. When the short-circuit end length LS is n / 2 times the wavelength of the high-frequency signal (n is a natural number), the short-circuit end length LS is 1/2 times the wavelength of the high-frequency signal (n = 1), 1 time ( In any case, the current of the line conductor 6 at the center of the slot 3 is maximized, and the slot can be efficiently excited by the magnetic field generated by the current. As a result, the laminated aperture antenna having good radiation efficiency. Can provide.

  3A and 3B are schematic views for explaining another example of the laminated aperture antenna of the present invention, wherein FIG. 3A is a top view and FIG. 3B is a B-BB sectional view.

  In FIG. 3, the same parts as those in FIG. 1 are denoted by the same reference numerals as in FIG. 1, wherein 9 is a shield ground layer, 10 is a connection through conductor, 11 is an upper dielectric layer, and 12 is an upper ground conductor layer. In this example of the present invention, a shield ground layer 9 having an opening larger than the slot 3 is arranged inside the dielectric layer 1 so that the opening corresponds to the slot 3, and the shield ground layer 9 is flush with the shield ground layer 9 along the opening. Since the ground conductor layer 2 is connected by a plurality of connecting through conductors 10, the outer periphery of the matching unit and the high frequency line 8 are electrically isolated, and unnecessary resonance that is easily excited in the outer periphery of the matching unit is transmitted through the high frequency line 8. Therefore, it is possible to provide a laminated aperture antenna having a stable performance without being excited in an electromagnetic wave mode of a high-frequency signal.

  In this example, since the upper dielectric layer 11 is disposed on the upper surface of the dielectric layer 1 and the upper ground conductor layer 12 is disposed on the upper surface of the upper dielectric layer 11, the electromagnetic wave leaks upward from the slot 3. It is possible to provide a laminated aperture antenna that is suppressed and has high radiation efficiency.

  It should be noted that the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS It is the schematic for demonstrating an example of the laminated | stacked aperture antenna of this invention, (a) is a top view, (b) is AAAA sectional drawing. It is the schematic for demonstrating another example of the lamination | stacking type | mold aperture surface antenna of this invention, (a) is a top view, (b) is B-BB sectional drawing. It is the schematic for demonstrating another example of the laminated | stacked aperture antenna of this invention, (a) is a top view, (b) is B-BB sectional drawing.

Explanation of symbols

1: Dielectric layer 2: Coplanar ground conductor layer 3: Slot 4: Shield through conductor 6: Line conductor 7: One end 8: High-frequency line 9: Shield ground layer
10: Connection through conductor
11: Upper dielectric layer
12: Upper grounding conductor layer G: Gap LO: Open end length LS: Short-circuit end length

Claims (7)

A high-frequency line composed of a line conductor formed on the upper surface of the dielectric layer and a coplanar ground conductor layer formed so as to surround one end of the line conductor, and the coplanar ground conductor layer orthogonal to the line conductor And a plurality of shield penetrating conductors formed inside the dielectric layer so as to surround the slot. A shield ground layer provided inside the dielectric layer having an opening larger than the slot and facing the slot, and formed so as to surround the opening along the opening in a plan view. 2. The multilayer aperture antenna according to claim 1, further comprising a plurality of connecting through conductors that electrically connect the shield ground layer and the same-surface ground conductor layer. The distance between one end of the line conductor is an open end and the center of the slot is (2n-1) / 4 times the wavelength of the high-frequency signal transmitted through the high-frequency line (n is a natural number). 3. A laminated aperture antenna according to claim 1 or 2, characterized in that: 3. The laminated aperture antenna according to claim 1, wherein one end of the line conductor is a short-circuited end electrically connected to the same surface ground conductor layer. 5. The stacked type according to claim 4, wherein a distance between the short-circuit end and the center of the slot is ½ of a slot width or n / 2 times the wavelength of the high-frequency signal (n is a natural number). Aperture antenna. 6. The multilayer opening according to claim 1, wherein an interval between the plurality of shield penetrating conductors is equal to or less than ¼ times the wavelength of the high-frequency signal in the dielectric layer. Planar antenna. 7. The upper dielectric layer formed on the upper surface of the dielectric layer, and the upper ground conductor layer formed on the upper surface of the upper dielectric layer. The laminated aperture antenna according to any one of the above.

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