JP2008182598A - Left-handed system transmission line, bypass filter and communication equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To constitute a left-handed transmission line in which a wide frequency range indicating left-handed system transmission line characteristics at low insertion loss is taken, a high pass filter having a wide passband and communication equipment having the same. <P>SOLUTION: A ground electrode 10 is formed on the lower surface (mounting surface to a circuit board) of a layered product 100, capacitor electrodes 21-27 are formed so that a plurality of capacitors are serially connected, each of which turns to the perpendicular direction to the ground electrode 10 and opposite to one another and inductor electrodes 30a, 30b are formed between capacitor electrodes other than capacitor electrodes 22a, 24a, 26a, 22c, 24c, 26c conducting to input/output electrodes 40a, 40b among the capacitor electrodes and the ground electrode. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a left-handed transmission line, a high-pass filter in the form of a left-handed transmission line, and a communication device including them.

  In general, when represented by an equivalent circuit using L and C, such as a coaxial line or a microstrip line used as a transmission line, L is connected in series, and C is connected in parallel between L and L. The configuration of a low-pass filter (LPF) having an LCL structure was adopted.

  Such a conventional transmission line has a characteristic that the phase is delayed as the signal propagates. On the other hand, as shown in Non-Patent Document 1, a left-handed transmission line having characteristics that the phase advances as the signal propagates, which is not found in conventional transmission lines, has been studied.

  In the left-handed transmission line, C is connected in series, and a configuration of a high-pass filter (HPF) having a CLC structure in which L is arranged in parallel between C and C is taken. Such a left-handed transmission line is expected to be applied to various devices by utilizing the characteristic that the phase advances as the signal propagates. For example, Patent Document 1 discloses a phased array antenna using a left-handed transmission line.

FIG. 1 is a diagram showing the structure of a phased array antenna disclosed in Patent Document 1. In FIG. The device 400 includes a series interdigital capacitor 402, a spiral short stub delay line 404 grounded to the ground via a central via 405, and a microstrip 401 and a T junction 403 connecting them.
“Left-handed metamaterials realize various parts that overturn common sense. Hurdle reduces insertion loss.” Nikkei Electronics 2006.1.2 p. 75-81 US Patent Application Publication No. 2005-0225492

  However, the conventional left-handed transmission line has a problem that the insertion loss increases due to the conductor loss generated in the capacitor electrode portion. Also, a capacitance component is generated between the capacitor electrode and the ground electrode, a capacitance component is also generated between the inductor electrode and the ground electrode, and further, an inductance component is entered in the capacitor electrode, so that it operates as a left-handed transmission line. The frequency range becomes narrow. In other words, these unnecessary components are equivalently low-pass filter elements. Therefore, when the operation of the low-pass filter becomes dominant, the high-frequency component of the signal is attenuated because it operates as a right-handed transmission line. Therefore, the usable frequency band becomes narrow.

  Accordingly, an object of the present invention is to provide a left-handed transmission line capable of widening a frequency range showing left-handed transmission line characteristics with low insertion loss, a high-pass filter having a wide passband, and a communication device including them. It is in.

In order to solve the above problems, the present invention is configured as follows.
(1) In a left-handed transmission line in which a plurality of capacitors are connected in series between input and output electrodes, and an inductor is connected between a connection portion between these capacitors and a ground electrode.
Capacitor electrodes constituting the capacitor facing each other are arranged so as to face a direction perpendicular to the surface on which the ground electrode is formed to constitute a left-handed transmission line.

  (2) The capacitor electrode is arranged so as to be parallel to a signal propagation direction which is a direction connecting the input / output electrodes.

  (3) The plurality of capacitor electrodes are arranged so that the capacitor electrodes adjacent to each other in the opposing direction are staggered in the signal propagation direction.

  (4) The plurality of capacitor electrodes are arranged in a plurality of rows in the facing direction, and are configured such that a certain capacitor electrode generates a capacitance with each of the other two capacitor electrodes sandwiching the capacitor electrode.

  (5) The inductor electrode is disposed between the capacitor electrode and a mounting surface on the circuit board on which the ground electrode is formed, or between the surface on which the ground electrode is formed.

  (6) The inductor electrode is arranged so as to face a mounting surface on the circuit board on which the ground electrode is formed or in a direction perpendicular to the surface on which the ground electrode is formed.

  (7) The inductor electrodes are arranged such that adjacent inductor electrodes are displaced in the facing direction of the capacitor electrodes.

  (8) The inductor electrode is a strip-like electrode having a linear shape, a spiral shape, or a meander line shape.

  (9) In the high pass filter according to the present invention, the left-handed transmission line is formed on the multilayer substrate having the surface on which the ground electrode is formed, and the input / output electrodes that are electrically connected to the input / output terminals of the capacitor electrode It shall be formed.

  (10) A communication apparatus according to the present invention includes the left-handed transmission line or the high-pass filter according to any one of the above in a high-frequency circuit unit.

According to the present invention, the following effects can be obtained.
(1) Since a plurality of capacitor electrodes face each other and face the vertical direction with respect to the ground electrode, an unnecessary capacitance component generated between the capacitor electrode and the ground electrode is extremely small and an ideal left-handed transmission line is obtained. Thus, the frequency range indicating the characteristics of the left-handed transmission line is widened.

  (2) By arranging the capacitor electrodes so as to be parallel to the signal propagation direction that connects the input and output electrodes, a configuration in which capacitors are connected in series in the signal propagation direction can be formed with a simple electrode pattern. Therefore, it can be made compact as a whole.

  (3) The plurality of capacitor electrodes are arranged so that the other capacitor electrodes adjacent in the facing direction are staggered, thereby eliminating the need for line electrodes that connect the capacitor electrodes adjacent in the signal propagation direction. A plurality of capacitors are sequentially connected in series with only a wide capacitor electrode, and conductor loss due to the capacitor electrode can be suppressed.

  (4) A plurality of capacitor electrodes are arranged in a plurality of rows in the opposing direction so that a certain capacitor electrode generates capacitance between each of the other two capacitor electrodes sandwiching the capacitor electrode. Capacitance obtained per total area can be increased and the overall size can be reduced.

  (5) By disposing the inductor electrode between the capacitor electrode and the ground electrode, the interval between the capacitor electrode and the ground electrode is widened, and unnecessary capacitance components generated between the capacitor electrode and the ground electrode are further suppressed.

  (6) Arranging the inductor electrode so as to face the vertical direction with respect to the ground electrode reduces the unnecessary capacitance component generated between the inductor electrode and the ground electrode and reduces the parallel capacitance component, so the left-handed transmission line As a result, the frequency range showing the characteristics becomes wider.

  (7) By disposing the inductor electrodes so that adjacent inductor electrodes are shifted in the opposing direction of the capacitor electrodes, unnecessary inductive coupling between inductors by the inductor electrodes and unnecessary capacitive coupling between inductor electrodes are suppressed. Therefore, the frequency range showing the characteristics as a left-handed transmission line is widened.

  (8) By making the inductor electrode a strip-like electrode having a linear shape, a spiral shape, or a meander line shape, current concentration at the edge of the inductor electrode is alleviated, and insertion loss can be reduced.

  (9) By configuring the left-handed transmission line as a high-pass filter, it can be used as a high-pass filter having a wide passband characteristic.

  (10) By providing the left-handed transmission line or the high-pass filter in the high-frequency circuit unit, it is possible to configure a communication device that takes advantage of the characteristics of the left-handed transmission line and the high-pass filter adopting the configuration.

<< First Embodiment >>
FIG. 2 is a diagram illustrating a configuration of the left-handed transmission line and the high-pass filter 110 according to the first embodiment. 2A is a perspective view of the high-pass filter 110, and FIG. 2B is a left side view thereof. However, each electrode is provided inside the dielectric ceramic laminate 100. In FIG. 2, the laminate 100 is drawn as transparent, and the internal electrode portion is shown by a solid line.

  FIG. 3 shows an example of an electrode pattern of an electrode forming layer for forming various electrodes provided in the laminated body. Capacitor electrodes 21a and 21b are formed on the electrode forming layer 61, and capacitor electrodes 22a, 22b and 22c are formed on the electrode forming layer 62, respectively. Capacitor electrodes 23a and 23b are formed on the electrode formation layer 63, and capacitor electrodes 24a, 24b and 24c are formed on the electrode formation layer 64, respectively. Similarly, capacitor electrodes 25a and 25b are formed on the electrode forming layer 65, capacitor electrodes 26a, 26b and 26c are formed on the electrode forming layer 66, and capacitor electrodes 27a and 27b are formed on the electrode forming layer 67, respectively. In the electrode formation layer 65, strip-shaped inductor electrodes 30a and 30b are formed, extending linearly downward from the capacitor electrodes 25a and 25b, respectively.

  In addition, vias 50a are formed in the electrode forming layers 61 to 67, respectively, for electrically connecting the capacitor electrodes 21a, 23a, 25a, and 27a in the thickness direction. Similarly, vias 50b that connect the capacitor electrodes 21b, 23b, 25b, and 27b in the thickness direction are formed in the electrode forming layers 61 to 67, respectively.

  Specifically, the electrode forming layer shown in FIG. 3 is a dielectric (or insulator) ceramic green sheet in which the capacitor electrode and the inductor electrode are printed with a conductive paste, and these ceramic green sheets are laminated, If necessary, ceramic green sheets without electrodes are also laminated to form a laminate 100 as shown in FIG. 2 and fired.

  The capacitor electrodes 21 to 27 are alternately shifted in the signal propagation direction (the direction from the left-hand front surface to the right rear surface in FIG. 2A, the direction perpendicular to the paper surface in FIG. 2B). Are arranged as follows.

  As described above, since the plurality of capacitor electrodes are opposed to each other through the ceramic layer, a capacitance is generated at the opposed portion. In the example shown in FIG. 2, seven rows of capacitor electrodes are arranged in the opposing direction, and the capacitor electrodes other than the capacitor electrodes 21a, 21b, 27a, and 27b are in contact with the other two capacitor electrodes that sandwich them. Capacitance occurs between each.

  An input / output electrode 40a is formed on the left-hand front surface of the multilayer body 100 in FIG. 2A, and an input / output electrode 40b is formed on the right rear surface. The capacitor electrodes 22a, 24a, and 26a are electrically connected to the input / output electrode 40a. The capacitor electrodes 22c, 24c, and 26c are electrically connected to the input / output electrode 40b, respectively. A ground electrode 10 is formed on the lower surface of the multilayer body 100, and the lower ends of the inductor electrodes 30 a and 30 b are electrically connected to the ground electrode 10.

  With such a structure, a plurality of capacitors are connected in series, and the inductor electrodes 30a and 30b are connected between the ground electrode formed on a surface different from the surface on which the input / output electrodes are formed and the capacitor electrodes other than the input / output terminals. Structure.

  The plurality of capacitor electrodes 21 to 27 are arranged so as to face the direction perpendicular to the surface on which the ground electrode 10 of the multilayer body 100 is formed, and the inductor electrodes 30 a and 30 b are formed as the capacitor electrodes 21 to 27 and the ground electrode 10. It is arranged between the surface (the bottom surface of the laminate 100 and the surface on which the high-pass filter 110 is mounted on the circuit board). Therefore, the unnecessary capacitance component generated between the capacitor electrode and the ground electrode is extremely small, making it an ideal left-handed transmission line and a wide frequency range (high-pass filter passband) indicating the characteristics of the left-handed transmission line. Become.

  In addition, by arranging the plurality of capacitor electrodes so that the other capacitor electrodes adjacent to each other in the opposite direction are staggered, a line electrode for connecting the capacitor electrodes adjacent to each other in the signal propagation direction is not necessary, A plurality of capacitors are sequentially connected in series only with a wide capacitor electrode, and conductor loss due to the capacitor electrode can be suppressed.

  Further, by arranging a plurality of capacitor electrodes in a plurality of rows in the opposing direction so that a certain capacitor electrode generates a capacitance between each of the other two capacitor electrodes sandwiching the capacitor electrode, Capacitance obtained per total area can be increased and the overall size can be reduced.

  Further, the inductor electrodes 30a and 30b are also arranged so as to face the direction perpendicular to the surface on which the ground electrode 10 is formed. As a result, capacitance components (parallel capacitance components) generated between the inductor electrodes 30a and 30b and the ground electrode 10 and between the inductor electrodes 30a and 30b and the capacitor electrodes 21 to 27 are reduced, so that the left-handed transmission line As a result, the frequency range showing the characteristics becomes wider.

  FIG. 4 is an equivalent circuit diagram of the high-pass filter. Here, the capacitor Caa is generated between the capacitor electrodes 22a, 24a, and 26a and the capacitor electrodes 21a, 23a, 25a, and 27a that alternately sandwich them, and the capacitor Cab is sandwiched between the capacitor electrodes 21a, 23a, 25a, and 27a. It is generated between the capacitor electrodes 22b, 24b and 26b. Similarly, the capacitor Cbb is generated between the capacitor electrodes 21b, 23b, 25b, and 27b and the capacitor electrodes 22b, 24b, and 26b sandwiched therebetween, and the capacitor Cbc is alternately sandwiched between the capacitor electrodes 22c, 24c, and 26c. It occurs between the capacitor electrodes 21b, 23b, 25b, and 27b.

  The inductor La is due to the inductor electrode 30a, and the inductor Lb is due to the inductor electrode 30b. The input / output terminals IN and OUT correspond to the input / output electrodes 40a and 40b, respectively. The ground terminal GND corresponds to the ground electrode 10.

  This transmission line functions as a left-handed transmission line including a series capacitor and a parallel inductor, and functions as a high-pass filter 110 as a whole including the input / output electrodes 40a and 40b and the ground electrode 10.

  In the example shown in FIG. 2, two stages of high-pass filter circuits based on CLC are provided in the laminate 100, but this can be further increased in number. Further, instead of forming the input / output electrodes 40a and 40b and utilizing the high-pass filter characteristic therebetween, the transmission line itself used in the high-pass frequency band of the high-pass filter may be used. For example, the CLC circuit shown in FIG. 4 can be configured as a line in a high-frequency circuit configured on a multilayer substrate.

<< Second Embodiment >>
5A and 5B are diagrams showing configurations of a left-handed transmission line and a high-pass filter according to the second embodiment. FIG. 5A is a perspective view of the high-pass filter 111, and FIG. 5B is a left side view thereof. . As in the case of FIG. 2, each electrode is provided inside a dielectric ceramic laminate 101. In FIG. 5, the laminate 101 is depicted as transparent, and the internal electrode portions are represented by solid lines.

  The difference from the first embodiment is the arrangement (extraction position) of the inductor electrode. In the example shown in FIG. 2, the inductor electrodes 30a and 30b are formed (in the same layer) on the electrode forming layer where the capacitor electrodes 25a and 25b are formed. In the example shown in FIG. 5, one inductor electrode 30a is connected to the capacitor electrode 27a. The other inductor electrode 30b is provided on the electrode forming layer on which the capacitor electrode 21a on the backmost surface is formed.

  In this way, by arranging the adjacent inductor electrodes so as to be shifted in the opposing direction of the capacitor electrodes, unnecessary inductive coupling between the inductors by the inductor electrodes and unnecessary capacitive coupling between the inductor electrodes can be suppressed, and the left-handed system The frequency range showing the characteristics as a transmission line is widened.

  In addition, what is necessary is just to make it the same relationship about adjacent inductor electrodes similarly, also when a CLC circuit continues 3 steps or more.

<< Third Embodiment >>
6A and 6B are diagrams showing configurations of a left-handed transmission line and a high-pass filter according to the third embodiment. FIG. 6A is a perspective view of the high-pass filter 112, and FIG. 6B is a left side view thereof. . As in the case of FIG. 2, each electrode is provided inside a dielectric ceramic laminate 102. In FIG. 6, the laminate 102 is depicted as transparent, and the internal electrode portions are represented by solid lines.

  In the first and second embodiments, the inductor electrode is constituted by the linear and strip-like electrodes, but in the third embodiment, the principal portions are constituted by the strip-like and spiral inductor electrodes 31a and 31b.

  Specifically, the inductor electrode 31a is formed on the electrode formation layer that forms the capacitor electrode 27a, and the inductor electrode 31c is formed on the electrode formation layer that forms the capacitor electrode 26a. The inductor electrodes 31a and 31c are electrically connected by a via 31e. Similarly, an inductor electrode 31b is formed on the electrode formation layer that forms the capacitor electrode 21a, and an inductor electrode 31d is formed on the electrode formation layer that forms the capacitor electrode 22a. The inductor electrodes 31b and 31d are electrically connected by a via 31f.

  Also in this third embodiment, the main part of the inductor electrode (the part excluding the vias 31e and 31f) is arranged in the direction perpendicular to the ground electrode 10 and the capacitor electrode with respect to 21 to 27. The winding directions of the spiral portions 31a and 31b of two adjacent inductor electrodes are opposite to each other.

  Originally, it is desirable that the inductor electrode is composed of one strip electrode extending in a direction perpendicular to the ground electrode and the capacitor electrode as shown in FIGS. 2 and 5 so as not to generate an unnecessary capacitance component. However, in order to obtain a desired inductance value when downsizing is required, it is effective to form the main part of the inductor electrode in a spiral shape in this way. With this structure, the height dimension from the ground electrode and the mounting surface can be reduced.

  Further, by making the winding direction of the spiral portion reverse between adjacent inductor electrodes, the magnetic field coupling between the inductor electrodes can be kept low. However, in this case, since the impedance of the transmission line becomes too low, the inductance value necessary for securing a desired impedance value becomes large, and miniaturization becomes difficult. As long as a frequency range acting as a left-handed transmission line can be secured, the winding directions of adjacent inductor electrodes may be formed in the same direction. Further, when three or more inductor electrodes are provided, an inductor electrode having the same winding direction and an inductor electrode having the opposite direction may be mixed.

<< Fourth Embodiment >>
7A and 7B are diagrams showing configurations of a left-handed transmission line and a high-pass filter according to the fourth embodiment. FIG. 7A is a perspective view of the high-pass filter 113, and FIG. 7B is a left side view thereof. is there. As in the case of FIG. 2, each electrode is provided inside a dielectric ceramic laminate 103. In FIG. 7, the laminate 103 is drawn as transparent, and the internal electrode portion is indicated by a solid line.

  In any of the first to third embodiments, the inductor electrode is disposed between the capacitor electrode and the ground electrode. In the fourth embodiment, the inductor electrode is disposed at a position adjacent to the stacking direction of the plurality of capacitor electrodes. . In general, it is desirable that the distance between the plurality of capacitor electrodes 21 to 27 and the ground electrode 10 be as far as possible so as not to generate unnecessary capacitance components therebetween. Since the unnecessary capacitance component can be kept small by arranging the capacitor electrodes perpendicularly to the surface of the capacitor 10, if the capacitor electrodes 21 to 27 are brought close to the ground electrode 10 as a whole, the inductor electrode is almost equivalent to the capacitor electrode. By arranging them at the same height, the overall height of the laminate can be reduced.

  In the example shown in FIG. 7, the two inductor electrodes 32a and 32b are formed on the same electrode formation layer. However, as in the case shown in FIG. You may arrange | position so that it may slip | deviate. As a result, unnecessary coupling between adjacent inductor electrodes can be suppressed, and the characteristics of an ideal left-handed transmission line can be brought close to.

<< Fifth Embodiment >>
FIG. 8 shows a configuration of a high-frequency circuit unit of a quad-band mobile phone terminal. The high-frequency circuit unit includes a triple-band chip set 203, a balanced-unbalanced filter module 200, a triple-band antenna switch module 201, and an antenna 202.

  The antenna switch module 201 is an antenna switch for GSM850 • 900 / DCS1800 / PCS1900, and the configuration of the highpass filter shown in the first to fourth embodiments is provided in the highpass filter portion that passes the DCS1800 / PCS1900 signal inside. Apply.

  A filter module 200 is connected to the GSM port, and the GSM850 and GSM900 are switched by the filter module 200. The quad-band chip set 203 is a chip set for GSM850 / GSM900 / DCS1800 / PCS1900, and operates as an RF (high frequency) front-end circuit for this quad-band. A baseband chip (not shown) is connected to the quadband chipset 203, and an input / output unit is provided on the baseband chip to constitute a mobile phone. The configuration of the transmission line portion in the high-pass filter shown in the first to fourth embodiments is applied to the transmission line portion in the filter module 200 or the quad-band chip set 203.

<< Other Embodiments >>
In each of the embodiments described above, the input / output electrodes 40a and 40b and the ground electrode 10 are formed on the laminate to be used as a high-pass filter. However, the mounting surface on the circuit board does not necessarily have a ground electrode. Good. In that case, the capacitor electrode and the inductor electrode may be arranged perpendicular to the mounting surface on the circuit board on which the ground electrode is formed. Further, for example, a ground electrode may be formed on the upper surface of the stacked body 100 in FIG. Even in this case, the ground electrode on the upper surface and the capacitor electrodes 21 to 27 are perpendicular to each other, and unnecessary capacitance components are suppressed.

  On the other hand, no ground electrode is formed on the surface of the multilayer body 100 parallel to the capacitor electrodes 21 to 27. If a ground electrode is formed on the surface, a sufficient distance from the capacitor electrodes 21 to 27 is ensured.

  In each embodiment, the ceramic green sheets are stacked in the direction in which the plurality of capacitor electrodes overlap. However, the present invention is not limited to the structure in which the capacitor electrode and the inductor electrode are configured in a stacked body. The material constituting the laminate is not limited to ceramic, and may be a resin such as a liquid crystal polymer.

  In each embodiment, it is desirable to configure the transmission line capacitor so as to have a continuous capacity. However, in this case, the necessary capacity for securing the necessary impedance increases. Configured to connect one or more intensive capacitance elements between inductor electrodes when there is a restriction on the dielectric constant or shape of the dielectric material and sufficient capacitance cannot be obtained. May be.

  Further, the inductor electrode is not limited to the pattern printing of the conductive paste on the ceramic green sheet, and may be constituted by a via. Moreover, you may comprise by the through hole which formed the conductor film in the inner surface.

  Further, in the third and fourth embodiments, the main part is a spiral inductor electrode, but the main part may be a meander line inductor electrode. In this case, the inductor electrode can be formed on the same plane without using vias.

It is a figure which shows the structure of the phased array antenna shown by patent document 1. FIG. It is a figure which shows the structure of the left-handed transmission line and high-pass filter which concern on 1st Embodiment. It is a figure which shows the example of the electrode pattern of the electrode formation layer which comprises the left-handed transmission line and the high pass filter. It is an equivalent circuit diagram of the left-handed transmission line and the high-pass filter. It is a figure which shows the structure of the left-handed transmission line and high-pass filter which concern on 2nd Embodiment. It is a figure which shows the structure of the left-handed transmission line and high-pass filter which concern on 3rd Embodiment. It is a figure which shows the structure of the left-handed transmission line and high-pass filter which concern on 4th Embodiment. It is a block diagram which shows the structure of the communication apparatus which concerns on 5th Embodiment.

Explanation of symbols

10-ground electrodes 21-27-capacitor electrodes 30-32-inductor electrodes 40-input / output electrodes 50-vias 61-67-electrode formation layers 100-103-laminated bodies 110-113-high-pass filters

Claims (10)

In the left-handed transmission line in which a plurality of capacitors are connected in series between the input and output electrodes, and an inductor is connected between the connection portion between these capacitors and the ground electrode,
A left-handed transmission line in which capacitor electrodes constituting the capacitor facing each other are arranged so as to face a direction perpendicular to a surface on which the ground electrode is formed.   The left-handed transmission line according to claim 1, wherein the capacitor electrode is arranged so as to be parallel to a signal propagation direction that is a direction connecting the input / output electrodes.   3. The left-handed transmission line according to claim 2, wherein the plurality of capacitor electrodes are arranged such that capacitor electrodes adjacent to each other in an opposing direction are alternately shifted in the signal propagation direction.   4. The plurality of capacitor electrodes are arranged in a plurality of rows in opposite directions so that a capacitance is generated between two capacitor electrodes at a position where a certain capacitor electrode sandwiches the capacitor electrode. Left-handed transmission line.   The left-handed transmission line according to claim 1, wherein the inductor electrode is disposed between the capacitor electrode and the ground electrode.   The left-handed transmission line according to claim 1, wherein the inductor electrode is disposed so as to face a direction perpendicular to a surface on which the ground electrode is formed.   The left-handed transmission line according to any one of claims 1 to 6, wherein the inductor electrode is disposed at a position shifted between adjacent inductor electrodes in a facing direction of the capacitor electrodes.   The left-handed transmission line according to any one of claims 1 to 7, wherein the inductor electrode is a strip-like electrode having a linear shape, a spiral shape, or a meander line shape.   A high-pass filter formed by forming the left-handed transmission line according to any one of claims 1 to 8 on a laminated substrate having a surface on which the ground electrode is formed, and forming the input / output electrodes on the laminated substrate.   A communication device comprising the left-handed transmission line according to claim 1 or the high-pass filter according to claim 9 in a high-frequency circuit unit.

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