JP2010028417A - Left-handed system resonator, and left-handed system filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a left-handed system filter which can extend pass band width, and can be made small in size and reduced in cost. <P>SOLUTION: The present invention is characterized by providing an aggregate 16a of first cells connected to a first connection point 19a provided between an input coupling element 15a and an interstage coupling element 15b with a first capacitor 17a one end of which is connected to the first connection point 19a and the other end of which is connected to a first ground 18a, and providing a set 16b of second cells connected to a second connection point 19b provided between the interstage coupling element 15b and an output coupling element 15c with a second capacitor 17b one end of which is connected to the second connection point 19b and the other end of which is connected to a second ground 18b. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a left-handed resonator and a left-handed filter used for a mobile phone or the like.

  The conventional left-handed filter has an input end 1 and an output end 2 as shown in FIG. An interstage coupling element 3 is interposed between the input terminal 1 and the output terminal 2, and a first series body 4 including a capacitor 4 a and an inductor 4 b is interposed between the input terminal 1 and the interstage coupling element 3. One end is electrically connected. An input coupling element 8 is connected between the input end 1 and one end of the first series body 4. Between the output end 2 and the interstage coupling element 3, one end of the second series body 5 including a capacitor 5a and an inductor 5b is electrically connected. An output coupling element 9 is connected between the output end 2 and one end of the second series body 5. One end of a first parallel body 6 composed of a capacitor 6a and an inductor 6b is electrically connected to the other end of the first series body 4. The first series body 4 and the first parallel body 6 constitute a first left-handed resonator. One end of a second parallel body 7 composed of a capacitor 7a and an inductor 7b is electrically connected to the other end of the second series body 5. The second series body 5 and the second parallel body 7 constitute a second left-handed resonator. The other ends of the first parallel body 6 and the second parallel body 7 are electrically connected to the ground. With the above configuration, a left-handed transmission line is formed on the dielectric layer.

For example, Non-Patent Document 1 is known as prior art document information relating to this application.
Sungtek Kahn and Jeong-ho Ju, Left-Handedness based Bandpass Filter Design for RFID UHF-Band applications, IEEE. , PP. 165-168 2007 Korea-Japan Microwave Conference

  As shown in FIG. 19, the bandwidth passing through the left-handed resonator used in such a conventional left-handed filter is the bandwidth in the vicinity of the point where the susceptance component becomes zero in the admittance of the left-handed resonator. Consists of. However, in the vicinity of the point where the susceptance component becomes zero, the change of the susceptance component is steeper and the bandwidth is narrower than that of the resonator used in the right-handed filter. For this reason, in order for the left-handed filter to function in the same bandwidth as the right-handed filter, more resonators are required than the right-handed filter, and there are problems in terms of miniaturization and cost.

  An object of the present invention is to provide a left-handed resonator in which the amount of change in the vicinity of a point where the susceptance component becomes zero among the admittance of the left-handed resonator is reduced, and further, by using this left-handed resonator, An object of the present invention is to provide a left-handed filter that can reduce the size and cost while expanding the bandwidth.

  One aspect of the present invention includes a series body having a first capacitor and a first inductor connected in series, a second capacitor and a second inductor connected in parallel, and one end of the series body. A left-handed resonator having at least one cell connected to one end and a parallel body having the other end connected to the ground, one end connected to one end or the other end of the series body, and the other end to the ground A third capacitor connected to is further provided.

  According to another aspect of the present invention, an input terminal, an output terminal, a coupling element group in which at least three or more coupling elements are connected in series between the input terminal and the output terminal, and at least one or more cells. Is a left-handed filter comprising a plurality of cell assemblies connected in series and a cell group in which one end of the cell assembly is connected in parallel between adjacent coupling elements of the coupling element group. The cells constituting the cell group include a series body having a first capacitor and a first inductor connected in series, a second capacitor and a second inductor connected in parallel, and one end of A left-handed filter composed of a parallel body that is electrically connected to one end of a series body and connected to the ground at the other end, and one end is electrically connected to each of adjacent coupling elements of the coupling element group. And the other end is connected to the ground. And further comprising a capacitor group having a plurality of capacitors.

  According to the present invention, since the bandwidth in the vicinity of the point where the susceptance component of the left-handed resonator is zero is widened, the bandwidth passing through the left-handed resonator is improved and the filter characteristics of the left-handed filter are improved. . This makes it possible to reduce the size and cost of the left-handed filter.

(Embodiment 1)
Hereinafter, the left-handed resonator according to the first embodiment of the present invention will be described with reference to the drawings.

  First, the concept of “cell” used in the present invention will be described with reference to FIG.

  As shown in FIG. 1, the cell 10 includes a series body 11 composed of a capacitor 11a and an inductor 11b, and a parallel body 12 composed of a capacitor 12a and an inductor 12b connected to one end of the series body 11. The The front-rear relationship between the capacitor 11a and the inductor 11b may be reversed.

  This cell 10 is a minimum unit structure of a right-handed / left-handed composite line called a metamaterial.

  Next, this metamaterial will be described.

  Usually, a substance existing in the natural world has a positive dielectric constant and a positive magnetic permeability, and this is called a right-handed medium. Here, the “right hand system” means that the three directions of the electric field direction, the magnetic field direction, and the wave traveling direction (phase propagation direction) of the electromagnetic wave are in the positional relationship of the right hand thumb, index finger, and middle finger.

  In contrast, a medium in which both permittivity and permeability are negative simultaneously is called a left-handed material. Here, the “left-handed system” means that the three directions of the electromagnetic field direction, the magnetic field direction, and the wave traveling direction (phase propagation direction) are in the positional relationship of the thumb, index finger, and middle finger of the left hand.

  Until now, the existence of a substance having only a negative dielectric constant or a substance having only a negative magnetic permeability has been discovered. For example, the former is plasma, and the latter is ferrite. However, no substance has been found in nature where both permittivity and permeability are negative at the same time. Therefore, such a medium is created by artificially making a fine structure and making the apparent dielectric constant and permeability negative. This is called an artificial medium.

  Next, the operation principle of the transmission line type metamaterial will be described.

  The electrical characteristics of a normal right-handed transmission line can be considered as an equivalent circuit in which an infinite number of infinitesimal sections composed of a series inductor 11b and parallel capacitors 12a are connected, as shown in FIG. This structure is called a pure right-handed transmission line (PRH TL).

  On the other hand, as shown in FIG. 3, the electrical characteristics of the left-handed transmission line can be considered as an equivalent circuit in which an infinite number of infinitesimal sections composed of a series capacitor 11a and parallel inductors 12b are connected. . This structure is called a pure left-handed transmission line (PLH TL).

  However, if the series capacitor 11a as shown in FIG. 3 is made, since it has a physical volume, a right-handed series inductor 11b as shown in FIG. 2 is inevitably generated as a parasitic component. It becomes.

  Further, when the parallel inductor 12b as shown in FIG. 3 is made, since it has a physical volume, a right-handed parallel capacitor 12a as shown in FIG. 2 is inevitably generated as a parasitic component. It becomes.

  Therefore, the metamaterial of the artificial medium that can be actually realized is a composite composed of a right-handed parallel capacitor 12a and a series inductor 11b, a left-handed series capacitor 11a, and a parallel inductor 12b as shown in FIG. It becomes a right-handed left-handed transmission line (Composite right / left-handed transmission line; CRLH TL).

This CRLH transmission line has the properties of both a left-handed transmission line and a right-handed transmission line. In the high frequency region, it has a right-handed transmission line property, and in the low frequency region, it has a left-handed transmission line property. The series body 11 including the left-handed capacitor 11a (C _L ) and the right-handed inductor 11b (L _R ) shown in FIG. 1 resonates at an angular frequency ω _se = 1 / (C _L * L _R ). A parallel resonant circuit in which a parallel body 12 including a left-handed inductor 12b (L _L ) and a right-handed capacitor 12a (C _R ) is anti-resonant at an angular frequency ω _sh = 1 / (L _L * C _R ) It becomes a resonance circuit. Here, the case of ω _se = ω _sh is called a balance case, and the frequency region of the right-handed transmission line and the frequency region of the left-handed transmission line are continuously connected. On the other hand, the case of ω _se ≠ ω _sh is called an unbalanced case, and a gap occurs between the frequency region of the right-handed transmission line and the frequency region of the left-handed transmission line, and the attenuation band in which electromagnetic waves cannot propagate It becomes.

  When a small gap or the like is formed at the input / output end of the CRLH transmission line to form an input / output coupling capacitor, the CRLH operates as a resonator in the same manner as a right-handed finite length line. In the right-handed finite-length line resonator, the lowest-order resonance having a half wavelength and the resonance of a harmonic that is an integer multiple thereof are recognized. On the other hand, in the CRLH resonator, the number of unique resonance frequencies is determined by the number of cells. For example, as shown in FIG. 17, in a CRLH resonator in which seven cells 10 are connected and sandwiched between capacitors 81 and 82 and the number of cells is n = 7, as shown in FIG. A + 6th order resonance to a + 6th order resonance exists as a resonance of a right-handed resonator. Further, as the resonance of the backward wave, the −1st order resonance to the −6th order resonance in which a standing wave having a half wavelength is present exists as the resonance of the left-handed resonator. Furthermore, there is a zero-order mode in which all cells vibrate synchronously at the same potential. As shown in FIG. 16, no standing wave is generated in the 0th-order mode, but this mode can be considered as a special resonance mode with an infinite wavelength.

  In the CRLH resonator, the + 1st order and −1st order resonance modes are the same as the standing wave distribution as shown in FIG. 16, and are the forward wave by the right-handed resonator and the left-handed resonator. Since the absolute value of the phase velocity of the backward wave is the same at a lower frequency in the left-handed system, the left-handed resonant frequency is necessarily lower.

  Therefore, the left-handed resonator can be made smaller than the conventional right-handed resonator. At this time, the −1st order resonance frequency is mainly determined by the capacitor 11a and the inductor 11b, which are left-handed elements, and the resonance frequency appears on the low frequency side as the respective element values increase. Generally, from the viewpoint of low loss, the frequency can be reduced by increasing the element value of the capacitor 11a. Incidentally, the amount of change at a frequency at which the susceptance component of the resonator becomes zero is proportional to the capacitor 11a and inversely proportional to the inductor 11b. That is, if the resonance frequency is lowered, the amount of change near the zero point where the susceptance component of the left-handed resonator becomes zero becomes steep. This means that the pass band of the filter is narrowed. Therefore, it is necessary to moderate the amount of change in the vicinity of the zero point of the susceptance component of the left-handed resonator.

  Hereinafter, the left-handed resonator according to the present embodiment will be described with reference to the drawings.

  As shown in FIG. 4, the left-handed resonator 100 according to the present embodiment includes a first cell 101 and a second cell 102 connected to the first cell 101. The first cell 101 includes a first series body 110 composed of a capacitor 110a and an inductor 110b, and a first parallel body 120 composed of a capacitor 120a and an inductor 120b. One end of the first parallel body 120 is connected to the input / output terminal 170, and the other end of the first parallel body 120 is connected to the ground. That is, one end of the capacitor 120a and one end of the inductor 120b are connected to the input / output end 170. The other end of the capacitor 120a and the other end of the inductor 120b are connected to the ground. One end of the first serial body 110 is connected to one end of the first parallel body 120. That is, one end of the capacitor 110a and one end of the inductor 110b are connected to one end of the capacitor 120a and one end of the inductor 120b. As shown in FIG. 4, one end of the first parallel body 120 is first connected to the input / output end 170, and one end of the first series body 110 is connected to one end of the first parallel body 120. Although connected, they may be connected in the reverse order. The second cell 102 includes a second series body 130 including a capacitor 130a and an inductor 130b, and a second parallel body 140 including a capacitor 140a and an inductor 140b. One end of the second parallel body 140 is connected to the other end of the first series body 110, and the other end of the second parallel body 140 is connected to the ground. That is, one end of the capacitor 140a and one end of the inductor 140b are connected to the other end of the capacitor 110a and the other end of the inductor 110b. The other end of the capacitor 140a and the other end of the inductor 140b are connected to the ground. One end of the second serial body 130 is connected to one end of the second parallel body 140. That is, one end of the capacitor 130a and one end of the inductor 130b are connected to one end of the capacitor 140a and one end of the inductor 140b. As shown in FIG. 4, one end of the second parallel body 140 is first connected to the other end of the first series body 110 corresponding to the other end of the first cell 101. One end of the second series body 130 is connected to the other end of the parallel body 140, but may be connected in the reverse order. As shown in FIG. 4, the capacitor 150 has one end connected to the first cell 101 via the input / output end 170 and the other end connected to the ground 160.

  By connecting the capacitor 150 in parallel with the left-handed resonator 100, the susceptance component of the capacitor 150 is added to the susceptance component of the left-handed resonator 100. As a result, the zero point of the susceptance component of the left-handed resonator 100 is shifted to the low frequency side, and the amount of change of the susceptance component of the left-handed resonator 100 in the vicinity thereof is a small value.

  Note that the other end of the second series body 130 shown in FIG. 4 may be connected to the ground via an inductor as a parasitic component. With this configuration, the resonator excites only left-handed and right-handed odd-order resonances. For this reason, the amount of change in the susceptance component of the resonator with respect to the frequency can be moderated.

  Next, a specific structure of the left-handed resonator 100 shown in FIG. 4 will be described with reference to FIGS. FIG. 5 is an exploded perspective view in which the left-handed resonator 200 having a specific structure is disassembled for each conductor pattern and conductor via layer. 6 is a cross-sectional view of the cross section taken along line AA in FIG.

  First, the connection relationship of the left-handed resonator 200 shown in FIGS. 5 and 6 will be described.

  The left-handed resonator 200 has a structure in which a gap between the ground conductors 201 and 202 arranged to face each other is filled with a dielectric 203. An input / output end 204 insulated from the ground conductor 202 is provided on the same plane as the ground conductor 202. A conductor pattern 206 is connected to the input / output end 204 via a via conductor 205. A conductor pattern 207 is provided opposite to the conductor pattern 206 with the dielectric 203 interposed therebetween. The conductor pattern 208 is opposed to the conductor pattern 207 with the dielectric 203 interposed therebetween. The conductor pattern 208 is connected to the ground conductor 201 via the via conductor 209. The conductor pattern 208 is connected to the conductor pattern 211 via the via conductor 210. The conductor pattern 208 is connected to the conductor pattern 213 through the via conductor 212. The conductor pattern 214 facing the conductor pattern 213 via the dielectric 203 is connected to the ground conductor 202 via the via conductor 215. The conductor pattern 216 is sandwiched between the conductor pattern 211 and the conductor pattern 213 via the dielectric 203. The conductor pattern 216 is connected to the ground conductor 201 via the via conductor 217. A conductor pattern 219 is connected to the conductor pattern 216 via a via conductor 218. In addition, the conductor pattern 221 is connected to the conductor pattern 216 via the via conductor 220. The conductor pattern 222 is sandwiched between the conductor pattern 219 and the conductor pattern 221 with the dielectric 203 interposed therebetween. The conductor patterns 206, 207, and 208 can increase the attenuation of the output when the left-handed resonator 200 resonates, and can clarify the change in the output. The ground conductors 201 and 202 are connected by side electrodes 223 and 224. Therefore, the potential of the ground conductor 201 and the potential of the ground conductor 202 can be kept at the same potential.

  Next, the correspondence between the structure of the left-handed resonator 200 shown in FIGS. 5 and 6 and the configuration of the left-handed resonator 100 shown in FIG. 4 will be described.

  First, which structure of the left-handed resonator 200 shown in FIGS. 5 and 6 corresponds to the first cell 101 shown in FIG. 4 will be described.

  The capacitor 110a shown in FIG. 4 has a structure in which the conductor pattern 211 and the conductor pattern 216 face each other via the dielectric 203, and a structure in which the conductor pattern 213 and the conductor pattern 216 face each other through the dielectric 203. Composed. The inductor 110b illustrated in FIG. 4 is mainly configured by the depth direction of the conductor pattern 216. The capacitor 120a shown in FIG. 4 is mainly configured by a structure in which a conductor pattern 211 and a ground conductor 201 are opposed to each other with a dielectric 203 interposed therebetween. The inductor 120b shown in FIG. 4 is configured by a via conductor 209.

  Next, which structure of the left-handed resonator 200 shown in FIGS. 5 and 6 corresponds to the second cell 102 shown in FIG. 4 will be described.

  The capacitor 130a shown in FIG. 4 has a structure in which the conductor pattern 219 and the conductor pattern 222 face each other through the dielectric 203, and a structure in which the conductor pattern 221 and the conductor pattern 222 face each other through the dielectric 203. Composed. The inductor 130b shown in FIG. 4 is mainly configured by the depth direction of the conductor pattern 216. The capacitor 140a shown in FIG. 4 is mainly configured by a structure in which a conductor pattern 219 and a ground conductor 201 are opposed to each other with a dielectric 203 interposed therebetween. The inductor 140b shown in FIG. 4 is configured by a via conductor 217.

  Next, which structure of the left-handed resonator 200 shown in FIGS. 5 and 6 corresponds to the capacitor 150 shown in FIG. 4 will be described.

  The capacitor 150 shown in FIG. 4 has a structure in which a conductor pattern 213 and a conductor pattern 214 are opposed to each other with a dielectric 203 interposed therebetween. Thus, when the left-handed resonator 200 has a laminated structure, the capacitor 150 can be provided by using a part of the left-handed resonator 200. Therefore, it is necessary to secure a new space for providing the capacitor 150. Absent. Therefore, the bandwidth can be increased without changing the size of the left-handed resonator with a small manufacturing cost.

(Modification 1)
Another specific structure of the left-handed resonator 100 shown in FIG. 4 will be described with reference to FIGS. FIG. 7 is an exploded perspective view in which the left-handed resonator 300 having a specific structure is disassembled for each conductor pattern and conductor via layer. 8 is a cross-sectional view of the cross section taken along line CC in FIG.

  First, the connection relationship of the left-handed resonator 300 shown in FIGS. 7 and 8 will be described.

  The left-handed resonator 300 has a structure in which a dielectric 303 is filled between ground conductors 301 and 302 arranged to face each other. An input / output terminal 304 insulated from the ground conductor 302 is provided on the same plane as the ground conductor 302. A conductor pattern 306 is connected to the input / output end 304 via a via conductor 305. A conductor pattern 307 is provided opposite to the conductor pattern 306 with the dielectric 303 interposed therebetween. The conductor pattern 308 faces the conductor pattern 307 with the dielectric 303 interposed therebetween. The conductor pattern 308 is connected to the ground conductor 301 via the via conductor 309. The conductor pattern 308 is connected to the conductor pattern 311 through the via conductor 310. The conductor pattern 308 is connected to the conductor pattern 313 via the via conductor 312. The conductor pattern 308 is connected to the conductor pattern 315 through the via conductor 314. Further, the conductor pattern 316 is sandwiched between the conductor pattern 313 and the conductor pattern 315 via the dielectric 303. The conductor pattern 316 is connected to the ground conductor 301 via the via conductor 317. In addition, a conductor pattern 319 is connected to the conductor pattern 316 via a via conductor 318. The conductor pattern 321 is connected to the conductor pattern 316 via the via conductor 320. The conductor pattern 322 is sandwiched between the conductor pattern 319 and the conductor pattern 321 with the dielectric 303 interposed therebetween. The conductor patterns 306, 307, and 308 can increase the attenuation of the output when the left-handed resonator 300 resonates, and can clarify the change in the output.

  Next, the correspondence between the structure of the left-handed resonator 300 shown in FIGS. 7 and 8 and the configuration of the left-handed resonator 100 shown in FIG. 4 will be described.

  First, which structure of the left-handed resonator 300 shown in FIGS. 7 and 8 corresponds to the first cell 101 shown in FIG. 4 will be described.

  The capacitor 110a shown in FIG. 4 has a structure in which the conductor pattern 313 and the conductor pattern 316 are opposed to each other through the dielectric 303, and a structure in which the conductor pattern 315 and the conductor pattern 316 are opposed to each other through the dielectric 303. Composed. The inductor 110b shown in FIG. 4 is mainly configured by the depth direction of the conductor pattern 316. The capacitor 120a shown in FIG. 4 is mainly configured by a structure in which a conductor pattern 313 and a ground conductor 301 are opposed to each other with a dielectric 303 interposed therebetween. The inductor 120b shown in FIG. 4 is configured by a via conductor 309.

  Next, which structure of the left-handed resonator 300 shown in FIGS. 7 and 8 corresponds to the second cell 102 shown in FIG. 4 will be described.

  The capacitor 130a shown in FIG. 4 has a structure in which the conductor pattern 319 and the conductor pattern 322 are opposed to each other through the dielectric 303, and a structure in which the conductor pattern 321 and the conductor pattern 322 are opposed to each other through the dielectric 303. Composed. The inductor 130b shown in FIG. 4 is mainly configured by the depth direction of the conductor pattern 316. The capacitor 140a shown in FIG. 4 is mainly configured by a structure in which a conductor pattern 319 and a ground conductor 301 face each other with a dielectric 303 interposed therebetween. The inductor 120b shown in FIG. 4 is configured by a via conductor 317.

  Next, which structure of the left-handed resonator 300 shown in FIGS. 7 and 8 corresponds to the capacitor 150 shown in FIG. 4 will be described.

  The capacitor 150 shown in FIG. 4 has a structure in which a conductor pattern 311 and a ground conductor 302 that is not a part of the left-handed resonator 300 are opposed to each other with a dielectric 303 interposed therebetween.

  The ground conductor 302 has a large area and is not a part of the left-handed resonator 300. Therefore, when the capacitor 150 is configured, the area of the conductor pattern 311 becomes almost the area of the capacitor 150 as it is, and the arrangement of the conductor pattern 311 is not affected by the size of the left-handed resonator 300. Therefore, the capacitor 150 shown in FIG. 4 can be formed in the left-handed resonator 300 with a large area.

  The ground conductors 301 and 302 are preferably connected by side electrodes 323 and 324.

(Embodiment 2)
Another aspect of the present invention will be described with reference to the drawings.

  First, the overall configuration of the left-handed filter in the present embodiment will be described with reference to FIG.

  As shown in FIG. 9, the left-handed filter 20 in the present embodiment includes an input end 13, an output end 14, a coupling element group 15 connected to the input end 13 and the output end 14, a coupling element group 15, A connected cell group 16, a capacitor group 17 connected to the coupling element group 15, and a ground group 18 connected to the capacitor group 17 are provided.

  The coupling element group 15 includes an input coupling element 15a having one end connected to the input terminal 13, an interstage coupling element 15b having one end connected to the other end of the input coupling element 15a, and one end connected to the other end of the interstage coupling element 15b. And an output coupling element 15c having the other end connected to the output end 14.

  The cell group 16 includes a first cell aggregate 16a and a second cell aggregate 16b.

  One end of the first cell assembly 16a is connected to a first connection point 19a provided between the input coupling element 15a and the interstage coupling element 15b. One end of the second cell aggregate 16b is connected to a second connection point 19b provided between the interstage coupling element 15b and the output coupling element 15c. The other end of the first cell assembly 16a is open or grounded. The other end of the second cell assembly 16b is open or grounded.

  Next, the configuration of the first cell assembly 16a, which is a left-handed resonator, will be described with reference to FIG.

  As shown in FIG. 10, the first cell assembly 16a includes a cell 401 having one end connected to the first connection point 19a and a cell 402 having one end connected in series to the other end of the cell 401. Is provided. In the present embodiment, the first cell assembly 16a is configured by two cells 401 and 402 connected in series, but may be configured by connecting at least one or more cells in series. For example, in the case where the −1st order resonance mode is used and the first cell aggregate 16a is composed of one cell, the other end of the first cell aggregate 16a is connected to the ground. Has been. When the first cell aggregate 16a is composed of two or more cells, the other end of the first cell aggregate 16a is open.

  The cell 401 includes a first series body 410 having one end connected to the first connection point 19a, and a first parallel body having one end connected to the first connection point 19a and the other end connected to the ground 420c. 420.

  The first series body 410 includes an inductor 410b having one end connected to the first connection point 19a and a capacitor 410a having one end connected to the other end of the inductor 410b. The arrangement of the capacitor 410a and the inductor 410b may be reversed.

  The first parallel body 420 has one end connected to the first connection point 19a, the other end connected to the ground 420c, one end connected to the first connection point 19a, and the other end connected to the ground 420c. And an inductor 420b connected to.

  The cell 402 includes a second series body 430 having one end connected to the other end of the capacitor 410a, and a second parallel body 440 having one end connected to the other end of the capacitor 410a and the other end connected to the ground 440c. Is provided.

  Second series body 430 includes an inductor 430b having one end connected to the other end of capacitor 410a and a capacitor 430a having one end connected to the other end of inductor 430b. The arrangement of the capacitor 430a and the inductor 430b may be reversed.

  The second parallel body 440 has one end connected to the other end of the capacitor 410a, the other end connected to the ground 440c, one end connected to the other end of the capacitor 410a, and the other end connected to the ground 440c. Inductor 440b.

  Next, the configuration of the second cell assembly 16b, which is a left-handed resonator, will be described with reference to FIG.

  As shown in FIG. 11, the second cell assembly 16b includes a cell 403 having one end connected to the second connection point 19b, and a cell 404 having one end connected in series to the other end of the cell 403. Is provided. In the present embodiment, the second cell assembly 16b is configured by two cells 403 and 404 connected in series, but may be configured by connecting at least one or more cells in series.

  The cell 403 includes a first serial body 450 having one end connected to the second connection point 19b, and a first parallel body having one end connected to the second connection point 19b and the other end connected to the ground 460c. 460.

  The first series body 450 includes an inductor 450b having one end connected to the second connection point 19b and a capacitor 450a having one end connected to the other end of the inductor 450b. The arrangement of the capacitor 450a and the inductor 450b may be reversed.

  The first parallel body 460 has a capacitor 460a having one end connected to the second connection point 19b and the other end connected to the ground 460c, one end connected to the second connection point 19b, and the other end connected to the ground 460c. And an inductor 460b connected to.

  The cell 404 includes a second series body 470 having one end connected to the other end of the capacitor 450a, and a second parallel body 480 having one end connected to the other end of the capacitor 450a and the other end connected to the ground 480c. Is provided.

  Second series body 470 includes inductor 470b having one end connected to the other end of capacitor 450a and capacitor 470a having one end connected to the other end of inductor 470b. The arrangement of the capacitor 470a and the inductor 470b may be reversed.

  The second parallel body 480 has one end connected to the other end of the capacitor 450a, the other end connected to the ground 480c, one end connected to the other end of the capacitor 450a, and the other end connected to the ground 480c. Inductor 480b.

  Next, the configuration of the capacitor group 17 will be described with reference to FIG.

  The capacitor group 17 has one end connected to the first connection point 19a, the other end connected to the first ground 18a, one end connected to the first connection point 19b, and the other end. Includes a second capacitor 17b connected to the second ground 18b.

  With such a configuration, as shown by the solid line in FIG. 12, the susceptance component of the admittance of the first cell assembly 16a and the second cell assembly 16b, which are left-handed resonators, in each frequency band is Since the frequency change in the vicinity where the susceptance component becomes zero becomes gentle, the first cell assembly 16a and the second cell assembly 16b, which are left-handed resonators, can have a wide bandwidth. it can. Therefore, a left-handed filter having the same bandwidth can be configured with a smaller number of resonators than before, and the left-handed filter can be downsized and the number of components can be reduced.

  Next, a specific structure of the left-handed filter 20 shown in FIG. 9 will be described with reference to FIGS. FIG. 13 is an exploded perspective view in which a left-handed filter 500 having a specific structure is disassembled for each conductor pattern and conductor via layer. FIG. 14 is a cross-sectional view of the cross section taken along the line EE in FIG.

  First, the connection relationship of the left-handed filter 500 shown in FIGS. 13 and 14 will be described.

  The left-handed filter 500 has a structure in which a gap between the ground conductors 501 and 502 arranged so as to face each other is filled with a dielectric 503.

  On the same plane as the ground conductor 502, an input end 504a insulated from the ground conductor 502 is provided. A conductor pattern 506a is connected to the input end 504a via a via conductor 505a. A conductor pattern 507 is provided opposite to the conductor pattern 506a via a dielectric 503. The conductor pattern 506a is connected to the ground conductor 501 through the via conductor 508a. The conductor pattern 506a is connected to the conductor pattern 510a via the via conductor 509a. The conductor pattern 506a is connected to the conductor pattern 512a through the via conductor 511a. The conductor pattern 506a is connected to the conductor pattern 514a via the via conductor 513a. The conductor pattern 515a is opposed to the conductor pattern 512a with the dielectric 503 interposed therebetween. The conductor pattern 515a faces the conductor pattern 514a with the dielectric 503 interposed therebetween. The conductor pattern 515a is connected to the ground conductor 501 through the via conductor 516a. The conductor pattern 515a is connected to the conductor pattern 518a through the via conductor 517a. The conductor pattern 515a is connected to the conductor pattern 520a through the via conductor 519a. The conductor pattern 521a is opposed to the conductor pattern 518a with the dielectric 503 interposed therebetween. The conductor pattern 521a is opposed to the conductor pattern 520a with the dielectric 503 interposed therebetween. At this time, the ground conductors 501 and 502 are preferably connected by the side electrodes 522 and 523.

  An output end 504 b insulated from the ground conductor 502 is provided on the same plane as the ground conductor 502. A conductor pattern 506b is connected to the output end 504b via a via conductor 505b. The conductor pattern 506b and the conductor pattern 507 are opposed to each other with the dielectric 503 interposed therebetween. The conductor pattern 506b is connected to the ground conductor 501 through the via conductor 508b. The conductor pattern 506b is connected to the conductor pattern 510b via the via conductor 509b. The conductor pattern 506b is connected to the conductor pattern 512b through the via conductor 511b. The conductor pattern 506b is connected to the conductor pattern 514b through the via conductor 513b. The conductor pattern 515b is opposed to the conductor pattern 512b with the dielectric 503 interposed therebetween. The conductor pattern 515b is opposed to the conductor pattern 514b with the dielectric 503 interposed therebetween. Conductive pattern 515b is connected to ground conductor 501 through via conductor 516b. The conductor pattern 515b is connected to the conductor pattern 518b through the via conductor 517b. The conductor pattern 515b is connected to the conductor pattern 520b through the via conductor 519b. The conductor pattern 521b is opposed to the conductor pattern 518b with the dielectric 503 interposed therebetween. The conductor pattern 521b is opposed to the conductor pattern 520b with the dielectric 503 interposed therebetween. At this time, the ground conductors 501 and 502 are preferably connected by the side electrodes 522 and 523.

  Next, the correspondence between the structure of the left-handed filter 500 shown in FIGS. 13 and 14 and the configuration of the left-handed filter 20 shown in FIG. 9 will be described.

  First, which structure of the left-handed filter 500 shown in FIGS. 13 and 14 corresponds to the first cell aggregate 16a shown in FIG. 10 will be described.

  The capacitor 410a shown in FIG. 10 has a structure in which the conductor pattern 512a and the conductor pattern 515a face each other via the dielectric 503, and a structure in which the conductor pattern 514a and the conductor pattern 515a face each other via the dielectric 503. Composed. The inductor 410b shown in FIG. 10 is mainly configured by the depth direction of the conductor pattern 515a. A capacitor 420a shown in FIG. 10 is mainly configured by a structure in which a conductor pattern 512a and a ground conductor 501 are opposed to each other with a dielectric 503 interposed therebetween. The inductor 420b shown in FIG. 10 is configured by a via conductor 508a. The capacitor 430a shown in FIG. 10 has a structure in which the conductor pattern 518a and the conductor pattern 521a are opposed to each other through the dielectric 503, and a structure in which the conductor pattern 520a and the conductor pattern 521a are opposed to each other through the dielectric 503. Composed. The inductor 430b shown in FIG. 10 is mainly configured by the depth direction of the conductor pattern 515a. The capacitor 440a shown in FIG. 10 is mainly configured by a structure in which a conductor pattern 518a and a ground conductor 501 are opposed to each other with a dielectric 503 interposed therebetween. The inductor 440b shown in FIG. 10 is configured by a via conductor 516a.

  Next, which structure of the left-handed filter 500 shown in FIGS. 13 and 14 corresponds to the second cell aggregate 16b shown in FIG. 10 will be described.

  The capacitor 450a shown in FIG. 11 has a structure in which the conductor pattern 512b and the conductor pattern 515b are opposed to each other through the dielectric 503, and a structure in which the conductor pattern 514b and the conductor pattern 515b are opposed to each other through the dielectric 503. Composed. The inductor 450b shown in FIG. 11 is mainly configured by the depth direction of the conductor pattern 515b. A capacitor 460a shown in FIG. 11 is mainly configured by a structure in which a conductor pattern 512b and a ground conductor 501 are opposed to each other with a dielectric 503 interposed therebetween. The inductor 460b shown in FIG. 11 is configured by a via conductor 508b. The capacitor 470a shown in FIG. 11 has a structure in which the conductor pattern 518b and the conductor pattern 521b are opposed to each other through the dielectric 503, and a structure in which the conductor pattern 520b and the conductor pattern 521b are opposed to each other through the dielectric 503. Composed. The inductor 470b shown in FIG. 11 is mainly configured by the depth direction of the conductor pattern 516b. A capacitor 480a shown in FIG. 11 is mainly configured by a structure in which a conductor pattern 518b and a ground conductor 501 are opposed to each other with a dielectric 503 interposed therebetween. The inductor 480b shown in FIG. 11 is configured by a via conductor 516b.

  Next, which structure of the left-handed filter 20 shown in FIGS. 13 and 14 corresponds to the coupling element group 15 shown in FIG. 9 will be described.

  The input coupling element 15a shown in FIG. 9 is configured by a via conductor 505a. The output coupling element 15c is constituted by a via conductor 505b. When the values of the input coupling element 15a and the output coupling element 15c are, for example, about 8 pF and the passband is about 2 GHz, the impedance of the input coupling element 15a and the output coupling element 15c is so small that it can be considered to be almost 0Ω. The input coupling element 15a and the output coupling element 15c may be removed according to the passband and the capacitor value. This is called tap feeding, and this tap feeding is used in this embodiment. Therefore, the capacitor constituting the input coupling element 15a is removed, and the via coupling 505a is formed by directly connecting the input end 504a and the conductor pattern 506a. Further, the capacitor constituting the output coupling element 15c is removed, and the output coupling element 15c is configured by a via conductor 505b in which the output end 504b and the conductor pattern 506b are directly connected. Further, the interstage coupling element 15b shown in FIG. 9 has a structure in which the conductor pattern 506a and the conductor pattern 507 are opposed to each other via the dielectric 503, and the conductor pattern 506b and the conductor pattern 507 are interposed via the dielectric 503. Are constructed by opposing structures.

  Next, which structure of the left-handed filter 20 shown in FIGS. 13 and 14 corresponds to the capacitor group 17 shown in FIG. 9 will be described.

  The capacitor 17a shown in FIG. 9 has a structure in which a conductor pattern 510a and a ground conductor 502 are opposed to each other with a dielectric 503 interposed therebetween. The capacitor 17b shown in FIG. 9 has a structure in which the conductor pattern 510b and the ground conductor 502 face each other with a dielectric 503 interposed therebetween. Note that the ground group 18 shown in FIG.

  At this time, the ground conductors 501 and 502 are preferably connected by the side electrodes 522 and 523.

  With such a configuration, the left-handed filter 20 in which the first cell assembly 16a and the second cell assembly 16b, which are left-handed resonators, are connected in parallel can be realized in a laminated structure. The capacitor 17a has a structure in which the conductor pattern 510a and the ground conductor 502 face each other through the dielectric 503, and the conductor pattern 510b and the ground conductor 502 face each other through the dielectric 503. By providing the capacitor 17b, the slope of the resonance frequency can be made gentle. Therefore, it becomes possible to design a left-handed filter with a smaller number of left-handed resonators than in the past, which is suitable for downsizing the left-handed filter.

  In the present embodiment, the input coupling element 15a and the output coupling element 15c are expressed as being directly connected by via conductors as shown in FIGS. 13 and 14, but this has a capacitance of 10 pF or more. That is, when the input coupling element 15a and the output coupling element 15c are smaller than the above values, it is desirable to actually provide a capacitor.

  The other end of the first cell aggregate 16a shown in FIG. 9 may be connected to the ground via an inductor as a parasitic component. The other end of the second cell aggregate 16b shown in FIG. 9 may be connected to the ground via an inductor as a parasitic component. With such a configuration, the resonator excites only the left-handed and right-handed odd-order resonances. As a result, the resonator does not excite even-order (0th-order) resonance that has been present as an unnecessary wave, so that the attenuation characteristic outside the passband is improved.

  According to the present invention, the bandwidth passing through the left-handed resonator can be improved, and the filter characteristics of the left-handed filter can be improved, which is useful in various electronic devices such as mobile phones. is there.

1 is an equivalent circuit diagram showing a cell of a left-handed resonator according to the first embodiment of the present invention. FIG. 3 is an equivalent circuit diagram of a right-handed transmission line of the left-handed resonator according to the first embodiment of the present invention. 1 is an equivalent circuit diagram of a left-handed transmission line of a left-handed resonator according to a first embodiment of the present invention. 1 is an equivalent circuit diagram of a left-handed transmission line of a left-handed resonator according to a first embodiment of the present invention. 1 is an exploded perspective view showing the structure of a left-handed resonator according to Embodiment 1 of the present invention. 5 is a cross-sectional view of the cross section taken along line AA in FIG. The disassembled perspective view which shows the structure of the left-handed resonator in the modification 1 of Embodiment 1 of this invention. 7 is a cross-sectional view of the cross section taken along line CC in FIG. Equivalent circuit diagram showing a left-handed filter according to Embodiment 2 of the present invention Equivalent circuit diagram showing a left-handed filter cell in Embodiment 2 of the present invention Equivalent circuit diagram showing a left-handed filter cell in Embodiment 2 of the present invention Frequency characteristics diagram of susceptance of left-handed filter according to Embodiment 2 of the present invention The disassembled perspective view which shows the structure of the left hand type | system | group filter in Embodiment 2 of this invention. 13 is a cross-sectional view of the cross section taken along line EE in FIG. Frequency characteristics of conventional left-handed filter Characteristic diagram showing voltage standing wave of CRLH resonator of conventional left-handed filter A perspective view of a conventional left-handed filter Equivalent circuit diagram of conventional left-handed filter Frequency characteristics of susceptance of conventional left-handed filter

Explanation of symbols

1, 13, 504a Input end 2, 14, 504b Output end 3, 15b Interstage coupling element 4, 110, 410, 450 First serial body 4a, 5a, 6a, 7a, 11a, 12a, 81, 82, 110a 120a, 130a, 140a, 150, 410a, 420a, 430a, 440a Capacitors 4b, 5b, 6b, 7b, 11b, 12b, 110b, 120b, 130b, 140b, 410b, 420b, 430b, 440b Inductors 5, 130, 430 470 Second serial body 6, 120, 420, 460 First parallel body 7, 140, 440, 480 Second parallel body 8, 15a Input coupling element 9, 15c Output coupling element 10 Cell 11 Serial body 12 Parallel Body 15 coupling element group 16 cell group 16a first cell aggregate 16b second cell aggregate 7 capacitor group 17a first capacitor 17b second capacitor 18 ground group 18a first ground 18b second ground 19a first connection point 19b second connection point 20,500 left-handed filter 100, 200, 300 left hand System resonator 101 First cell 102 Second cell 160, 420c, 440c, 460c, 480c Ground 170, 204, 304 Input / output ends 201, 202, 301, 302, 501, 502 Ground conductors 203, 303, 503 Dielectric Body 205, 209, 210, 212, 215, 217, 218, 220, 305, 309, 310, 312, 314, 317, 318, 320, 505a, 508a, 509a, 511a, 513a, 516a, 517a, 519a, 505b , 508b, 509b, 511b, 513b, 516b, 517b, 519b Via conductor 206, 207, 208, 211, 213, 214, 216, 219, 221, 222, 306, 307, 308, 311, 313, 315, 316, 319, 321, 322 , 506a, 507, 510a, 512a, 514a, 515a, 518a, 520a, 521a, 506b, 510b, 512b, 514b, 515b, 518b, 520b, 521b Conductor pattern 223, 224, 323, 324, 522, 523 Side electrode 401 , 402, 403, 404 cells

Claims (8)

A series body having a first capacitor and a first inductor connected in series;
A left hand having at least one cell having a second capacitor and a second inductor connected in parallel, one end of which is connected to one end of the series body and the other end is connected to the ground. A system resonator,
A left-handed resonator, further comprising a third capacitor having one end connected to one end or the other end of the series body and the other end connected to the ground. 2. The apparatus according to claim 1, further comprising a parasitic component having one end electrically connected to one end or the other end of the series body to which the third capacitor is not connected and the other end connected to the ground. The left-handed resonator as described. The left-handed resonator according to claim 2, wherein the parasitic component is an inductor. The left-handed resonator according to claim 1, further comprising a dielectric that contains the cell and the third capacitor. An input end;
An output end;
A coupling element group in which at least three coupling elements are connected in series between the input end and the output end;
A plurality of cell assemblies in which at least one cell is connected in series, and a cell group in which one end of the cell assembly is connected in parallel between adjacent coupling elements of the coupling element group. Prepared,
The cells that make up this group of cells are
A series body having a first capacitor and a first inductor connected in series;
A left-handed filter comprising a parallel body having a second capacitor and a second inductor connected in parallel, one end electrically connected to one end of the series body and the other end connected to the ground. And
The left-handed system further comprising a capacitor group having a plurality of third capacitors, one end of which is electrically connected between adjacent coupling elements of the coupling element group and the other end of which is connected to the ground. filter. It further comprises a parasitic component group consisting of a plurality of parasitic components,
Each of the parasitic components constituting the parasitic component group is characterized in that one end is electrically connected to the other end of the aggregate of the cells constituting the cell group and the other end is connected to the ground. The left-handed filter according to claim 5. The left-handed filter according to claim 6, wherein the parasitic component constituting the parasitic component group is an inductance component. The left-handed filter according to claim 5, further comprising a dielectric body including the cell group and the capacitor group.

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