The present invention relates to a structure body, layered structure of a structure body, and an antenna structure.
In a device using a high frequency electromagnetic wave such as an antenna device or a wireless communication device, a structure body including a transmission line a part of which is hollow is used in order to suppress a loss at the transmission line. An art related to such a structure body is disclosed in Patent Literature 1 (PTL 1).
PTL1 discloses an art related to a suspended substrate. A suspended substrate is provided with parallel flat plates including two conductor planes that are substantially parallel to each other and a dielectric substrate disposed between the parallel flat plates in a floating manner. The dielectric substrate is provided with a signal line that forms a transmission line. Having a hollow part as a part of the gap between the parallel flat plates reduces dielectric material, thereby suppressing dielectric loss. As a result, a high frequency signal is transmitted efficiently.
[PTL] EP0608889
A problem in the related art is the difficulty in suppressing an electromagnetic wave that propagates inside the suspended substrate,
Generally, at a point with discontinuous characteristic impedance or in a situation that high-mode is generated, there is a possibility that a part of the high frequency signal that propagates in the transmission line does not propagate along the signal line and is emitted as an electromagnetic wave, and leaks to the inside of the parallel flat plates. When the electromagnetic wave leaks to the inside of the parallel flat plates (hereinafter the electromagnetic wave that leaks is referred to as leaked electromagnetic wave), the leaked electromagnetic wave has a possibility to cause coupling to other devices or to emit to the outside. Thus, sometimes leakage countermeasure such as short-circuiting the parallel flat plates is performed. However, since a suspended substrate has a hollow region in a part of the substrate, it is difficult to short-circuit the parallel flat plates.
An objective of the present invention is to provide a structure body that suppresses the leaked electromagnetic wave that propagates inside the suspended substrate, a layered structure of the structure body, and an antenna structure.
A structure body in the present invention comprises: a first conductor plane and a second conductor plane disposed in parallel;
a dielectric plane that is disposed in parallel to the first conductor plane and the second conductor plane between the first conductor plane and the second conductor plane via a hollow region;
a first transmission line that is disposed on a surface facing the first conductor plane of the dielectric plane, at least one of whose ends is an open end; and
a second transmission line that is disposed on a surface facing the second conductor plane of the dielectric plane, at least one of whose ends is an open end;
wherein the first transmission line and the second transmission line are electrically connected to each other.
A layered structure in the present invention comprises: a first conductor plane and a second conductor plane disposed in parallel;
a third conductor plane that is disposed in parallel to the first conductor plane and the second conductor plane, and in parallel to the surface of the second conductor plane opposite to the surface facing the first conductor plane;
a first dielectric plane that is disposed in parallel to the first conductor plane and the second conductor plane between the first conductor plane and the second conductor plane via a hollow region;
a second dielectric plane that is disposed in parallel to the second conductor plane and the third conductor plane between the second conductor plane and the third conductor plane via another hollow region;
a first transmission line that is disposed on a surface of the first dielectric plane facing the first conductor plane, and on a surface of the second dielectric plane facing the surface of the second conductor plane, and at least one end of which is an open end;
a second transmission line that is disposed on a surface of the first dielectric plane facing the second conductor plane and on a surface of the second dielectric plane facing the third conductor plane, and at least one end of which is an open end;
a first suspended transmission line that is disposed on the first dielectric plane, and one end of which is an open end; and
a second suspended transmission line that is disposed on the second dielectric plane, and one of which is an open end;
wherein the second conductor plane includes an opening at a position opposing to an open end of the first suspended transmission line and an open end of the second suspended transmission line;
wherein the first transmission line and the second transmission line are electrically connected to each other; and
a plurality of unit structures are disposed to surround open ends of the first suspended transmission line and the second suspended transmission line, where the unit structure is configured by the first transmission line and the second transmission line.
An antenna structure in the present invention comprises: a first conductor plane and a second conductor plane disposed in parallel;
a dielectric plane that is disposed in parallel to the first conductor plane and the second conductor plane between the first conductor plane and the second conductor plane via a hollow region;
a first transmission line that is disposed on a surface facing the first conductor plane of the dielectric plane, at least one end of which is an open end; and
a second transmission line that is disposed on a surface of the dielectric plane facing the second conductor plane, at least one end of which is an open end; and
a suspended transmission line that is disposed on the dielectric plane, and one of which is an open end;
wherein the first conductor plane includes an opening at a position opposing to an open end of the suspended transmission line;
the first transmission line and the second transmission line are electrically connected to each other; and
a plurality of unit structures are disposed to surround an open end of the suspended transmission line, wherein the unit structure is configured by the first transmission line and the second transmission line.
The effect of the present invention is that the structure body, the layered structure thereof and the antenna structure suppress the leaked electromagnetic wave that propagates inside the suspended substrate.
Hereinafter, with reference to the drawings, the example embodiments of the present invention are described in detail. Note that, in each drawing and each example embodiment in the description, same reference numerals are used to such the component provided with similar function.
The structure body 100 is configured by provided with a parallel flat plate configured by provided with a first conductor plane 101 and a second conductor plane 102 that are substantially parallel to each other, a dielectric plane 103 disposed therebetween, a first transmission line 104 having the dielectric plane 103 as the support member and disposed on the surface of the first conductor plane 101 side, a second transmission line 105 that is disposed on the surface of the second conductor plane 102 side of the dielectric plane 103, and a conductor via 106 that connects the first transmission line 104 and the second transmission 105.
The dielectric plane 103 has hollow regions 107 and 108, sandwiched with the first conductor plane 101 and sandwiching with the second conductor plane 102, respectively.
One end of each of the first transmission line 104 and the second transmission line 105 is an open end, and the other ends are coupled to each other by the conductor via 106. The first transmission line 104 and the second transmission line 105 are disposed in such a way that each open end does not overlap in the top view (refer to
For example, in the structure body 100, the first transmission line 104 and the second transmission line 105 may be disposed in a V-shape as illustrated in
The structure body 100 may not necessarily use the conductor via 106 in the case the first transmission line 104 and the second transmission line 105 can be connected to each other, as illustrated in
With the structure body 100 of the example embodiment, when the impedance Z between the parallel flat plates configured by provided with the first conductor plane 101 and the second conductor plane 102 is substantially zero or inductive, the propagation constant is an imaginary number, and therefore the propagation of the electromagnetic wave can be suppressed, Especially, the suppressing effect is high when the impedance Z is substantially zero.
In the structure body 100, in the case the leaked electromagnetic wave 113 propagates between the parallel flat plates configured by provided with the first conductor plane 101 and the second conductor plane 102 (i.e. in the case of propagation through a unit structure including the first transmission line 104, the second transmission line 105 and the conductor via 106), electric field distribution is induced between the first transmission line 104 and the first conductor plane 101, and between the second transmission line 105 and the second conductor plane 102, and the first transmission line 104 and the second transmission line 105 operate as stubs.
It is assumed that the input impedance between the transmission line 104 and the conductor plane 101 when viewed from the conductor via 106 side to the open end side of the first transmission line 104 is Zin1, and the input impedance between the transmission line 105 and the conductor plane 102 when viewed from the conductor via 106 side to the open end side of the second transmission line 105 is Zin2. Here, the impedance Z between the parallel flat plates configured by provided with the first conductor plane 101 and the second conductor plane 102 is expressed substantially by the sum of Zin1, the inductance of the conductor via 106 and Zin2.
In order to suppress the leaked electromagnetic wave 113, the first transmission line 104 and the second transmission line 105 are preferably designed to satisfy the following relationship: for example, the length L from the connection to the conductor via 106 to each open end is substantially L=(2n+1)×λ/4, where λ is the wavelength at the operating frequency. Here, the parameter n is an integer equal to or larger than 0, and n=0, 1, 2, 3, . . . , n.
With the structure body 100 taking the above configuration, in the first transmission line 104 and the first conductor plane 101, the input impedance Zin1 between the transmission line 104 and the conductor plane 101 when seeing the open end side of the first transmission line 104 from the conductor via 106 side becomes substantially zero. This means that the first transmission line 104 and the first conductor plane 101 are short-circuited.
Similarly, in the second transmission line 105 and the second conductor plane 102., the input impedance Zin2 between the transmission line 105 and the conductor plane 102 when seeing the open end side of the second transmission line 105 from the conductor via 106 side becomes substantially zero. This means that the second transmission line 105 and the second conductor plane 102 are short-circuited.
The above effect and the inductance of the conductor via 106, the structure body 100 can make the impedance Z between the first conductor plane 101 and the second conductor plane 102 inductive, as illustrated in the right side of
In the structure body 100 of the first example embodiment, the coupling between the first transmission line 104 and the second transmission line 105 can be suppressed by disposing the first transmission line 104 and the second transmission line 105 in such a way as to the open ends thereof do not overlap in a top surface view.
In the example embodiment, the first transmission line 104 and the second transmission line 105 may be any length as long as the impedance Z between the parallel flat plates configured by provided with the first conductor plane 101 and the second conductor plane 102 is substantially zero or inductive.
Scattering parameters related to the structure body 100 of the example embodiment are illustrated in
With reference to
Note that the connection of the first transmission line 104 and the second transmission line 105 may not necessarily be the ends of the first transmission line 104 and the second transmission line 105, but may be any points except for the open ends.
The thicknesses h1 and h2 of the hollow regions 107 and 108 of the first example embodiment respectively may be equal or unequal to each other.
The structure body 200 of the second example embodiment of the present disclosure is described with reference to
The structure body 200 in
The structure body 300 of the third example embodiment of the present disclosure is described with reference to
The structure body 300 of the third example embodiment is different from the structure body 100 of the first example embodiment in that the shape of the first transmission line 104 and the second transmission line 105 of the first example embodiment are not linear shape but folding back shape. Regarding to the structure body 300 of the third example embodiment, by flexibly mounting the shape of the first transmission line 304 and the second transmission line 305, the size of the structure body 300 can be decreased.
With the structure body 300 of the example embodiment, in a similar manner to the first example embodiment, the propagation of the leaked electromagnetic wave in the parallel flat plates can be suppressed.
In the example embodiment, the first transmission line 304 and the second transmission line 305 are U-shaped folding back shape however, other shape may be adopted. For example, L-shape, curved shape, spiral shape, meandering shape or the like as illustrated in
The structure body 400 of the fourth example embodiment of the present disclosure is described with reference to
In the structure body 400 of the fourth example embodiment, each of the first transmission line 404 and the second transmission line 405 has a plurality of branch wires. in the example embodiment, the number of branch wires is assumed to be two however, the number may be equal to or more than three. The two branch wires that are included by each of the first transmission line 404 and the second transmission line 405 respectively have different lengths L1 and L2, from the connection portion to the conductor via 106 to each open end. The branch wires whose lengths are different operate in different frequencies respectively, and the branch wires are adjusted to satisfy the following conditions.
The L1 is designed to satisfy L1=(2s+1)×λ1/4 for the λ1 that is the wavelength at the operating frequency. Here, the parameter s is an integer equal to or larger than 0 and s=0, 1, 2, . . . , s.
Similarly, the L2 is designed to satisfy L=(2t+1)×λ2/4, for the λ2 that is the wavelength at the operating frequency. Here, the parameter t is an integer equal to or larger than 0, and t=0, 1, 2, . . . , t.
With the configuration described above, since the first transmission line 404 and the second transmission line 405 perform resonance operation at a plurality of frequencies originating from the length of each of the plurality of branch wires, the structure body 400 operates at a plurality of frequencies.
The structure body 500 of the fifth example embodiment of the present disclosure is described with reference to
The structure body 500 of the fifth example embodiment is different from the first example embodiment in that a suspended strip line 512 configured by provided with a third transmission line 509 and a fourth transmission line 510 and a plurality of conductor vias 511 on the dielectric plane 103 in addition to the configuration of the structure body 100 of the first example embodiment is disposed. On the structure body 500, a plurality of unit structure including a first transmission line 104, a second transmission line 105, and a conductor via 106 surrounding the suspended strip line 512 formed on the suspended substrate may be disposed. For example, the unit structure may be disposed periodically.
In the suspended strip line 512, the fourth transmission line 510 and a plurality of conductor vias 511 may not necessarily be used, and only the third transmission line 509, as illustrated in
The structure body 600 of the sixth example embodiment of the present disclosure is described with reference to
The structure body 600 of
Resonator operates when the length L of the transmission line 609 roughly satisfying relationship as L=n×λ/2, where λ is the wavelength at the operation frequency and n is an integer equal to or larger than 1, and the leaked electromagnetic wave that propagates in the parallel flat plates can be suppressed. Note that the thicknesses h1 and h2 of the hollow regions 107 and 108 may be equal or unequal to each other.
In
In
In the example embodiment, the first transmission line 604 and the second transmission line 605 have a linear shape; however, other shape may he adopted. For example, similar to the first transmission line 304 and the second transmission line 305 of the third example embodiment, various folding back shapes may be adopted.
The layered structure 700 of the seventh example embodiment of the present disclosure is described with reference to
The layered structure 700 of the seventh example embodiment is the configuration when the structure body 500 of the fifth example embodiment is layered.
The layered structure 700 illustrated in
The unit structure 720 is configured by the first transmission line 104, the second transmission line 105 and the conductor via 106 of the first example embodiment. Note that the conductor via 106 may not necessarily be included. By replacing the dielectric plane 103 of the first example embodiment with the first dielectric plane 704 and the second dielectric plane 705 of the example embodiment, the unit structure 720 can be configured as the first dielectric plane 704 and the second dielectric plane 705.
The unit structure 720 nay be disposed periodically in the example embodiment.
The high frequency signal that propagates within the suspended. strip line is transmitted from the first suspended strip line 711 to the second suspended strip line 712 via the slot 713 disposed on the second conductor plane 702, as illustrated by the arrows in
In the layered structure 700, when the plurality of unit structures 720 are not disposed, a part of the high frequency signal transmitted from the first suspended strip line 711 intrudes to the slot 713 and transmitted to the second suspended strip line 712, however, a part of the remaining high frequency signal has a possibility to propagate, not along the second suspended strip line 712, but to the inside of the two parallel flat plates formed by the first conductor plane 701, the second conductor plane 702 and the third conductor plane 703 as a leaked electromagnetic wave. This is because the characteristic impedance at the slot 713 and the open end of the suspended strip line is discontiguous with regard to the suspended strip line 711 and 712. In order to prevent the propagation of the leaked electromagnetic wave, a plurality of unit structures 720 are disposed in
The antenna structure 800 of the eighth example embodiment of the present disclosure is described with reference to
The antenna structure 800 illustrated in
The slot 808 operates as an antenna element that receives the electromagnetic wave from outside and transmits to the suspended strip line 805, or in an opposite manner, emits the high frequency signal transmitted from the suspended strip line 805 to the outside.
The plurality of unit structures 720 are disposed to prevent the propagation of the leaked electromagnetic wave from the suspended strip line 805 to the inside of the parallel flat plates formed by the first conductor plane 101 and the second conductor plane 102, similar to the seventh example embodiment.
The structure body 900 of the sixth example embodiment of the present disclosure is described with reference to
The structure body 900 of
The material used for the spacer 907 may be any of conductor, dielectric, or magnetic substance as long as the mechanical strength is secured.
The spacer 907 is preferably disposed at a position far from the unit structure 720 in such a way as not to affect the operation thereof. The spacer 907 may not necessarily be electrically connected to the first conductor plane 101, the second conductor plane 102 and the dielectric plane 103.
The present invention has been described above with each example embodiment and the variation, however, the present invention is not limited to the above example embodiments. Within the scope of the present invention, the configuration and the detail of the present invention may be applied with various changes and combinations that may be understood by a person skilled in the art.
Each of the example embodiments described above may be described as the supplementary note below and is not limited.
A structure body including:
a first conductor plane and a second conductor plane disposed in parallel;
a dielectric plane that is disposed in parallel to the first conductor plane and the second conductor plane between the first conductor plane and the second conductor plane via a hollow region;
a first transmission line that is disposed on a surface facing the first conductor plane of the dielectric plane; and
a second transmission line that is disposed on a surface facing the second conductor plane of the dielectric plane;
in which the first transmission line and the second transmission line are electrically connected to each other.
The structure body according to claim 1, in which the first transmission line and the second transmission line are provided with a plurality of branch wires whose lengths are different, respectively.
The structure body according to supplementary note 2, in which lengths Lm from the connection of the first transmission line and the second transmission line the end of the plurality of branch wires satisfy Lm=(2n+1)×λm/4, where λm is a wavelength at an operating frequency and n is an integer equal to or larger than 0.
The structure body according to supplementary note 1, further including at least one suspended transmission line disposed on the dielectric plane,
in which the first transmission line and the second transmission line are disposed around the suspended transmission line.
The structure body according to the supplementary note 4, including a plurality of unit structures configured by the first transmission line and the second transmission line,
in which the plurality of unit structures are disposed to surround the suspended transmission line.
This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2016-70663, filed on Mar. 31, 2016, the disclosure of which is incorporated herein in its entirety by reference.
The application examples of the present invention are a communication device, antenna device or the like.
100, 200 . . . 600, 900 Structure body
101 First conductor plane
102 Second conductor plane
103, 203 Dielectric plane
104, 304, 404, 604 First transmission line
105, 305, 405, 605 Second transmission line
106, 606 Conductor via
107, 108 Hollow region
509 Third transmission line
510 Fourth transmission line
511 Conductor via
512, 805 Suspended strip line
609 Transmission line
700 Layered structure
701 First conductor plane
702 Second conductor plane
703 Third conductor plane
704 First dielectric plane
705 Second dielectric plane
711 First suspended strip line
712 Second suspended strip line
720 Unit structure
800 Antenna structure
713, 808 Slot
907 Spacer
Number | Date | Country | Kind |
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2016-70663 | Mar 2016 | JP | national |
Filing Document | Filing Date | Country | Kind |
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PCT/JP2017/012379 | 3/27/2017 | WO | 00 |