JP2010199950A - Bandpass filter, and wireless communication module and wireless communication apparatus using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bandpass filter which has two wide pass bands and also has an attenuation electrode formed between the two pass bands, and to provide a wireless communication module and wireless communication apparatus using the same. <P>SOLUTION: The bandpass filter includes: first to fourth resonance electrodes 30a and 30b, and 30c and 30d forming a first pass band; fifth to eighth resonance electrodes 31a and 31b, and 31c and 35 forming a second pass band; a first input/output coupling electrode 40a coupled opposite with the first and fifth resonance electrodes 30a and 31a; and a second input/output coupling electrode 40b coupled opposite with the fourth and seventh resonance electrodes 30d and 31c, in which is arranged between layers of a stack, wherein the first to seventh resonance electrodes 30a, 30b, 30c, 30d, 31a, 31b, 31c are 1/4-wavelength resonators and the eighth resonance electrode 35 is a 1/2-wavelength resonator. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a bandpass filter, a wireless communication module and a wireless communication device using the same, and more particularly to a bandpass filter having two pass bands, a wireless communication module and a wireless communication device using the same. is there.

  In recent years, UWB has attracted attention as a new communication means. UWB realizes large-capacity data transfer using a wide frequency band over a short distance of about 10 m. For example, according to US FCC (Federal Communication Commission) regulations, a plan to use a frequency band of 3.1 to 10.6 GHz It has become. Thus, the feature of UWB is that it uses a very wide frequency band.

  In recent years, research on ultra-wideband filters that can be used for UWB has been actively conducted. For example, a bandpass filter that applies the principle of a directional coupler has a passband width of a specific bandwidth (bandwidth / center). There is a report that a broadband characteristic exceeding 100% is obtained in (frequency) (for example, see Non-Patent Document 1).

  On the other hand, as a filter often used conventionally, there is known a band-pass filter configured by connecting a plurality of quarter-wavelength stripline resonators to each other (see, for example, Patent Document 1).

JP 2004-180032 A

“Ultra-wideband bandpass filter using microstrip-CPW broadside coupling structure” Proceedings of the March 2005 IEICE General Conference C-2-114 p.147

  However, the band-pass filters proposed in Non-Patent Document 1 and Patent Document 1 each have problems, and are not suitable for UWB band-pass filters.

  For example, the bandpass filter proposed in Non-Patent Document 1 has a problem that the passband width is too wide. In other words, UWB basically uses a frequency band of 3.1 GHz to 10.6 GHz, but the International Telecommunication Union wireless communication section is about 3.1 to 4.7 GHz avoiding 5.3 GHz used in IEEE802.11.a. A plan that divides into a low band using a band and a high band using a band of about 6 GHz to 10.6 GHz has been developed. Therefore, the filters used for the UWB Low Band and High Band each require a pass bandwidth of about 40% to 50% in the specific band and attenuation at 5.3 GHz. The band-pass filter proposed in Non-Patent Document 1 having characteristics exceeding 100% cannot be used because its pass band width is too wide.

  Further, the pass band width of a bandpass filter using a conventional quarter wavelength resonator is too narrow, and even if the pass band width of the band pass filter described in Patent Document 1 is intended to be wide, it is 10 It was less than%. Therefore, it cannot be used as a band-pass filter for UWB requiring a wide pass bandwidth corresponding to 40% to 50% in the specific band.

  The present invention has been devised in view of such problems in the prior art, and the purpose thereof is wide, which can cover a UWB low band filter and a high band filter with a single filter. An object of the present invention is to provide a bandpass filter having two passbands and having an attenuation pole formed between the two passbands, and a radio communication module and a radio communication device using the same.

  The band-pass filter of the present invention includes a laminate in which a plurality of dielectric layers are laminated, a ground electrode disposed on at least one of the upper surface and the lower surface of the laminate, and one between the first layers of the laminate. Band-shaped first to fourth resonance electrodes that are arranged side by side in such a manner that the end and the other end are staggered, each having one end grounded and functioning as a quarter-wave resonator, and the laminate A band-like fifth to seventh resonance electrodes which are sequentially arranged side by side between a second layer different from the first layer of the first electrode and each end is grounded and functions as a quarter wavelength resonator; A band-shaped first portion disposed between layers located on the opposite side of the first layer with a second layer interposed therebetween and disposed in parallel to the sixth resonance electrode and electromagnetically coupled; and Electromagnetically placed in close proximity to the seventh resonant electrode An eighth resonance electrode comprising a band-shaped second portion to be coupled and a connecting portion connecting one ends of the first and second portions, and functioning as a half-wave resonator; and the first of the multilayer body. The first and the second resonance electrodes disposed between the first layer and the second layer, the first and the fifth resonance electrodes being electromagnetically coupled to face the region extending over half of the length direction. At least half of the length direction of the fourth and seventh resonance electrodes disposed between the input / output coupling electrode and the interlayer located between the first interlayer and the second interlayer of the multilayer body A second input / output coupling electrode that is electromagnetically coupled to face the crossing region, and the one end of the first resonance electrode and the one end of the fifth resonance electrode are located on the same side The one end of the fourth resonance electrode is the same as the one end of the seventh resonance electrode. The one end of the fifth resonance electrode and the other end of the sixth resonance electrode are located on the same side, and the one end of the sixth resonance electrode and the first end The other end of one part is located on the same side, the one end of the seventh resonance electrode and the other end of the second part are located on the same side, and the first input / output coupling The electrode includes a first input / output point to which an electric signal is input or output, and the first input / output point is the first and fifth in the length direction of the first input / output coupling electrode. The first input / output coupling electrode is located farther from the one end of the first and fifth resonance electrodes than the center of the portion facing the resonance electrode, and an electric signal is input to or output from the second input / output coupling electrode. A second input / output point is provided, and the second input / output point is located in the length direction of the second input / output coupling electrode. The fourth and seventh resonance electrodes are positioned farther from the one end of the fourth and seventh resonance electrodes than the center of the opposed portion to the fourth and seventh resonance electrodes. And a second passband formed by the fifth to eighth resonance electrodes. The first passband is formed by the four resonance electrodes.

  The wireless communication module of the present invention includes the bandpass filter of the present invention.

  A wireless communication device of the present invention includes an RF unit including the bandpass filter of the present invention, a baseband unit connected to the RF unit, and an antenna connected to the RF unit. It is.

  According to the bandpass filter of the present invention, the first to fourth resonance electrodes are arranged side by side sequentially so that one end and the other end are staggered, and are electromagnetically coupled to each other in an interdigital manner. The fifth to eighth resonance electrodes are arranged so that the open ends of adjacent resonance electrodes are staggered and electromagnetically coupled to each other in an interdigital manner. Therefore, the electromagnetic field coupling between the first to fourth resonance electrodes and the electromagnetic field coupling between the fifth to eighth resonance electrodes can be strengthened, and thus the passage formed by the first to fourth resonance electrodes. The band and the pass band formed by the fifth to eighth resonance electrodes can be widened.

  According to the bandpass filter of the present invention, the first input / output coupling electrode is opposed to a region extending over half the length direction of the first and fifth resonance electrodes, and an electric signal is input or output. The first input / output point is one end of the first and fifth resonance electrodes with respect to the length direction of the first input / output coupling electrode rather than the center of the portion facing the first and fifth resonance electrodes. It is located on the far side. As a result, the first input / output coupling electrode is electromagnetically coupled to the first and fifth resonance electrodes in an interdigital manner on the broad side, and is thus strongly electromagnetically coupled to the first and fifth resonance electrodes.

  Furthermore, according to the bandpass filter of the present invention, the second input / output coupling electrode is opposed to a region extending over half of the length direction of the fourth and seventh resonance electrodes, and an electric signal is input or output. The second input / output point is one end of the fourth and seventh resonance electrodes in the length direction of the second input / output coupling electrode rather than the center of the portion facing the fourth and seventh resonance electrodes. It is located on the far side. As a result, the second input / output coupling electrode is electromagnetically coupled to the fourth and seventh resonant electrodes in an interdigital manner on the broad side, and is thus strongly electromagnetically coupled to the fourth and seventh resonant electrodes.

  Therefore, according to the bandpass filter of the present invention, the first input / output coupling electrode is strongly electromagnetically coupled to the first and fifth resonance electrodes, and the second input / output coupling electrode is the fourth and seventh. Since it is strongly electromagnetically coupled to the resonance electrode, a bandpass filter having excellent pass characteristics that is flat and has low loss over the entire two wide passbands can be obtained.

  Still further, according to the band-pass filter of the present invention, the first to fourth resonance electrodes that form the first passband between the first input / output coupling electrode and the second input / output coupling electrode; The fifth to eighth resonance electrodes that form the second passband are electrically connected in parallel. In the first to fourth resonance electrodes, adjacent resonance electrodes are mainly capacitively coupled by interdigital electromagnetic field coupling, and adjacent resonance electrodes in the fifth to eighth resonance electrodes. The electrodes are mainly capacitively coupled by interdigital electromagnetic field coupling. Further, the first input / output coupling electrode is mainly capacitively coupled to the first and fifth resonance electrodes by interdigital electromagnetic field coupling, and the second input / output coupling electrode is the fourth and 7 and the resonance electrode are mainly capacitively coupled by interdigital electromagnetic field coupling. The first to seventh resonance electrodes are formed of quarter-wave resonators, and the eighth resonator is formed of a half-wave resonator. Therefore, according to the bandpass filter of the present invention, in the frequency region located between the first passband and the second passband, the electric signal transmitted through the first to fourth resonant electrodes Since the attenuation pole can be formed by canceling out the electrical signals transmitted through the fifth to eighth resonance electrodes, the frequency region is located between the first passband and the second passband. It is possible to obtain a bandpass filter having good pass characteristics in which the amount of attenuation is secured.

  According to the wireless communication module of the present invention and the wireless communication device of the present invention, the loss of the signal passing over the entire area of the two wide passbands is small, and the signal is attenuated by the attenuation pole formed between the two passbands. By using the band-pass filter of the present invention with a sufficient amount for filtering the communication signal, the attenuation of the communication signal passing through the band-pass filter is reduced and the noise is also reduced. For this reason, the reception sensitivity is improved and the amplification degree of the communication signal can be reduced, so that the power consumption in the amplifier circuit is reduced. Furthermore, signals of two communication bands can be filtered with the band-pass filter of the present invention. Therefore, it is possible to obtain a high-performance wireless communication module and wireless communication device that are small in size, have high reception sensitivity, and consume less power.

It is an external appearance perspective view which shows typically the band pass filter of the 1st example of embodiment of this invention. It is a typical exploded perspective view of the band pass filter shown in FIG. It is a top view which shows typically the upper and lower surfaces and interlayer of a band pass filter shown in FIG. It is the Q-Q 'line sectional view of Drawing 1. It is a disassembled perspective view which shows typically the band pass filter of the 2nd example of embodiment of this invention. It is a disassembled perspective view which shows typically the band pass filter of the 3rd example of embodiment of this invention. It is a block diagram which shows typically the radio | wireless communication module and radio | wireless communication apparatus of the 4th example of embodiment of this invention. It is a disassembled perspective view which shows typically the band pass filter of a 1st comparative example. It is a disassembled perspective view which shows the band pass filter of a 2nd comparative example typically. It is a figure which shows the simulation result of the electrical property of the bandpass filter of the 2nd example of embodiment of this invention. It is a figure which shows the simulation result of the electrical property of the bandpass filter of the 3rd example of embodiment of this invention. It is a figure which shows the simulation result of the electrical property of the band pass filter of a 1st comparative example. It is a figure which shows the simulation result of the electrical property of the band pass filter of a 2nd comparative example.

Hereinafter, a bandpass filter of the present invention will be described in detail with reference to the accompanying drawings.
(First example of embodiment)
FIG. 1 is an external perspective view schematically showing a band-pass filter of a first example of an embodiment of the present invention. FIG. 2 is a schematic exploded perspective view of the bandpass filter shown in FIG. FIG. 3 is a plan view schematically showing the upper and lower surfaces and the layers of the bandpass filter shown in FIG. FIG. 4 is a cross-sectional view taken along the line QQ ′ of FIG.

  As shown in FIGS. 1 to 4, the band-pass filter of this example includes a laminate 10, a first ground electrode 21, a second ground electrode 22, a first annular ground electrode 23, and a second Ring-shaped ground electrode 24, first to fourth resonance electrodes 30a, 30b, 30c, 30d, fifth to eighth resonance electrodes 31a, 31b, 31c, 35, and first input / output coupling electrode 40a. , A second input / output coupling electrode 40b, a first input / output terminal electrode 60a, and a second input / output terminal electrode 60b. The laminate 10 is formed by laminating a plurality of dielectric layers 11. The first ground electrode 21 is disposed on the lower surface of the multilayer body 10. The second ground electrode 22 is disposed on the upper surface of the multilayer body 10. The band-shaped first to fourth resonance electrodes 30a, 30b, 30c, and 30d are sequentially arranged side by side between the first layers of the stacked body 10 so that one end and the other end are staggered. One end is grounded and functions as a quarter wavelength resonator. The first annular ground electrode 23 is disposed between the first layers of the multilayer body 10 so as to surround the first to fourth resonance electrodes 30a, 30b, 30c, and 30d. One ends of the resonance electrodes 30a, 30b, 30c, and 30d are connected. The band-like fifth to seventh resonance electrodes 31a, 31b, 31c are sequentially arranged side by side between the second layers of the multilayer body 10, and one end thereof is grounded to function as a quarter wavelength resonator. . The second annular ground electrode 24 is disposed between the second layers of the multilayer body 10 so as to surround the fifth to seventh resonance electrodes 31a, 31b, 31c, and the fifth to seventh resonances. One ends of the electrodes 31a, 31b, 31c are connected. The eighth resonance electrode is disposed between the third layer located on the opposite side of the first layer with the second layer of the laminate 10 interposed therebetween, and is adjacent to the sixth resonance electrode 31b in parallel. A first band-shaped portion 35a which is disposed and electromagnetically couples; a second band-shaped portion 35b which is disposed close to and parallel to the seventh resonance electrode 31c; and a first and second portions 35a and 35b. It consists of a connecting portion 71c that connects one end to the other, and functions as a half-wave resonator. The first input / output coupling electrode 40a is disposed between a first layer and a second layer of the multilayer body 10 and is disposed between the first layer and the second layer, and the first and fifth resonance electrodes 30a, 31a. Electromagnetic field coupling is performed in opposition to a region extending over half of the length direction. The second input / output coupling electrode 40b is disposed between the third layers of the laminate 10, and is opposed to a region extending over half of the length direction of the fourth and seventh resonance electrodes 30d and 31c. Join the field. The first input / output terminal electrode 60a is disposed on the upper surface of the multilayer body 10 with the second ground electrode 22 therebetween, and is connected to the first input / output coupling by the through conductor 50 penetrating the dielectric layer 11. It is connected to the first input / output point 45a of the electrode 40a. The second input / output terminal electrode 60b is disposed on the upper surface of the multilayer body 10 with a gap between the second ground electrode 22 and the second input / output coupling by the through conductor 50 penetrating the dielectric layer 11. It is connected to the electrode 40b.

  The band-pass filter of this example having such a configuration has an external circuit connected to the first input / output point 45a of the first input / output coupling electrode 40a via the first input / output terminal electrode 60a and the through conductor 50, for example. When the electric signal from the first input electrode is input, the first resonance electrode 30a electromagnetically coupled to the first input / output coupling electrode 40a is excited, whereby the first to fourth resonance electrodes that are electromagnetically coupled to each other are excited. The through conductor 50 and the second input / output terminal electrode from the second input / output point 45b of the second input / output coupling electrode 40b in which 30a, 30b, 30c, 30d resonate and electromagnetically couple with the fourth resonant electrode 30d. An electrical signal is output to an external circuit via 60b. At this time, since the signal in the first frequency band including the frequency at which the first to fourth resonance electrodes 30a, 30b, 30c, and 30d resonate selectively passes, the first pass band is thereby formed. .

  Further, when an electric signal from an external circuit is input to the first input / output point 45a of the first input / output coupling electrode 40a via the first input / output terminal electrode 60a and the through conductor 50, the first input When the fifth resonance electrode 31a electromagnetically coupled to the output coupling electrode 40a is excited, the fifth to eighth resonance electrodes 31a, 31b, 31c, and 35 that are electromagnetically coupled to each other resonate, and the seventh An electric signal is output from the second input / output point 45b of the second input / output coupling electrode 40b electromagnetically coupled to the resonance electrode 31c to the external circuit through the through conductor 50 and the second input / output terminal electrode 60b. At this time, since a signal in the second frequency band including the frequency at which the fifth to eighth resonance electrodes 31a, 31b, 31c, and 35 resonate selectively passes, a second pass band is thereby formed. .

  In this way, the bandpass filter of this example functions as a bandpass filter having two passbands having different frequencies.

  According to the bandpass filter of this example having such a configuration, the first to fourth resonance electrodes 30a, 30b, 30c, and 30d are sequentially arranged side by side so that one end and the other end are alternated. Thus, the electromagnetic field coupling between the first and fourth resonance electrodes 30a, 30b, 30c, and 30d can be widened. can do.

  Further, according to the bandpass filter of this example, one end of the fifth resonance electrode 31a and the other end of the sixth resonance electrode 31b are located on the same side, and one end of the sixth resonance electrode 31b. And the other end of the first portion 35a are located on the same side, and one end of the seventh resonance electrode 31c and the other end of the second portion 35b are located on the same side. The eighth resonance electrodes 31a, 31b, 31c, and 35 are arranged so that the open ends of adjacent resonance electrodes are staggered, and are electromagnetically coupled to each other in an interdigital manner. Therefore, the electromagnetic coupling between the fifth to eighth resonance electrodes 31a, 31b, 31c, and 35 can be strengthened, so that the passage formed by the fifth to eighth resonance electrodes 31a, 31b, 31c, and 35 is achieved. The bandwidth can be widened.

  Further, according to the bandpass filter of this example, the first resonance electrode 30a and the fifth resonance electrode are arranged so that one end thereof is located on the same side, and the first input / output coupling is provided. The electrode 40a is disposed so as to face a region extending over half of the length direction of the first and fifth resonance electrodes 30a and 31a. Then, the first input / output point 45a has a first and a fifth in the length direction of the first input / output coupling electrode 40a from the center of the facing portion to the first and fifth resonance electrodes 30a and 31a. It is located on the side far from one end of the resonance electrodes 30a and 31a. As a result, the first input / output coupling electrode 40a is electromagnetically coupled to the first and fifth resonance electrodes 30a, 31a on the broad side in an interdigital manner, so that the first and fifth resonance electrodes 30a, 31a Strong electromagnetic coupling.

  Furthermore, according to the bandpass filter of the present invention, the one end of the fourth resonance electrode 30d and the one end of the seventh resonance electrode are arranged on the same side, and the second input / output is arranged. The coupling electrode 40b is disposed so as to face a region extending over half of the length direction of the fourth and seventh resonance electrodes 30d and 31c. The second input / output point 45b has a fourth and seventh higher than the center of the portion facing the fourth and seventh resonance electrodes 30d and 31c in the length direction of the second input / output coupling electrode 40b. It is located on the side far from one end of the resonance electrodes 30d and 31c. As a result, the second input / output coupling electrode 40b is electromagnetically coupled to the fourth and seventh resonance electrodes 30d and 31c on the broad side in an interdigital manner, so that the fourth and seventh resonance electrodes 30d and 31c Strong electromagnetic coupling.

  Therefore, according to the bandpass filter of the present invention, the first input / output coupling electrode 40a is strongly electromagnetically coupled to the first and fifth resonance electrodes 30a and 31a, and the second input / output coupling electrode 40b is Since the fourth and seventh resonance electrodes 30d and 31c are strongly electromagnetically coupled, a band pass filter having excellent pass characteristics that is flat and low loss over the entire two wide pass bands can be obtained.

  Still further, according to the band-pass filter of the present invention, the first to fourth resonances that form the first passband between the first input / output coupling electrode 40a and the second input / output coupling electrode 40b. The electrodes 30a, 30b, 30c, 30d and the fifth to eighth resonance electrodes 31a, 31b, 31c, 35 forming the second passband are electrically connected in parallel. In the first to fourth resonance electrodes 30a, 30b, 30c, and 30d, adjacent resonance electrodes are mainly capacitively coupled by interdigital electromagnetic field coupling, and the fifth to eighth In the resonance electrodes 31a, 31b, 31c, and 35, adjacent resonance electrodes are mainly capacitively coupled by interdigital electromagnetic field coupling. Further, the first input / output coupling electrode 40a is mainly capacitively coupled to the first and fifth resonance electrodes 30a, 31a by interdigital electromagnetic field coupling, and the second input / output coupling electrode 40b. Is mainly capacitively coupled to the fourth and seventh resonance electrodes 30d and 31c by interdigital electromagnetic field coupling. The first to seventh resonance electrodes 30a, 30b, 30c, 30d, 31a, 31b, and 31c are composed of quarter wavelength resonators, and the eighth resonance electrode 35 is composed of a half wavelength resonator. Therefore, according to the bandpass filter of this example, the first to fourth resonance electrodes 30a, 30b, 30c, 30d are interposed in the frequency region located between the first passband and the second passband. The attenuation pole can be formed by canceling the electric signal transmitted through the fifth and eighth resonance electrodes 31a, 31b, 31c, and 35 to form the attenuation pole. A bandpass filter having good pass characteristics in which attenuation in the frequency region located between the first passband and the second passband is ensured.

In the band-pass filter of this example, as the material of the dielectric layer 11, for example, a resin such as an epoxy resin or a ceramic such as a dielectric ceramic can be used. For example, a dielectric ceramic material such as BaTiO ₃ , Pb ₄ Fe ₂ Nb ₂ O ₁₂ , or TiO ₂ and a glass material such as B ₂ O ₃ , SiO ₂ , Al ₂ O ₃ , or ZnO, and 800 to 1200 ° C. Glass-ceramic materials that can be fired at relatively low temperatures are preferably used. The thickness of the dielectric layer 11 is set to about 0.01 to 0.1 mm, for example.

  Examples of the materials for the various electrodes and through conductors described above include conductive materials mainly composed of Ag alloys such as Ag, Ag-Pd, and Ag-Pt, Cu-based, W-based, Mo-based, and Pd-based conductive materials. Are preferably used. The thickness of various electrodes is set to 0.001 to 0.2 mm, for example.

The band pass filter of this example can be manufactured as follows, for example. First, an appropriate organic solvent or the like is added to and mixed with the ceramic raw material powder to produce a slurry, and a ceramic green sheet is formed by a doctor blade method. Next, a through hole for forming a through conductor is formed on the obtained ceramic green sheet using a punching machine, and a ceramic paste is filled with a conductor paste containing a conductor such as Ag, Ag-Pd, Au, or Cu. The same conductive paste as described above is applied to the surface of the green sheet using a printing method to produce a ceramic green sheet with a conductive paste. Next, these ceramic green sheets with conductor paste are laminated, pressed using a hot press device, and fired at a peak temperature of about 800 ° C. to 1050 ° C.
(Second example of embodiment)
FIG. 5 is an exploded perspective view schematically showing a band-pass filter of a second example of the embodiment of the present invention. Note that in this example, only differences from the first example described above will be described, and the same components will be denoted by the same reference numerals, and redundant description will be omitted.

  In the bandpass filter of this example, as shown in FIG. 5, the first input / output coupling electrode 40a includes a strip-shaped first lower electrode 41a, a strip-shaped first upper electrode 42a, and a first The connection conductor 43a and the first connection auxiliary conductor 44a are configured. The first lower electrode 41a is disposed in the interlayer A located between the first interlayer and the second interlayer of the multilayer body 10 and extends over half of the length of the first resonance electrode 30a. Electromagnetic field coupling is performed opposite to the region. The first upper electrode 42a is disposed in an interlayer B located between the interlayer A and the second interlayer of the multilayer body 10, and is opposed to a region extending over half of the length direction of the fifth resonance electrode 31a. And electromagnetic coupling. The first connection conductor 43a connects one end sides of the first lower electrode 41a and the first upper electrode 42a. The first connection auxiliary conductor 44a connects the other end sides of the first lower electrode 41a and the first upper electrode 42a. The first input / output point 45a is located at one end of the first lower electrode 41a.

In the bandpass filter of this example, the second input / output coupling electrode 40b includes a strip-shaped second lower electrode 41b, a strip-shaped second upper electrode 42b, a second connection conductor 43b, The second connection auxiliary conductor 44b is used. The second lower electrode 41b is disposed between the layers A of the stacked body, and is electromagnetically coupled so as to face a region extending over half of the length direction of the fourth resonance electrode 30d. The second upper electrode 42b is disposed between the layers B of the multilayer body 10 and is electromagnetically coupled to face the region extending over half of the length direction of the seventh resonance electrode 31c. The second connection conductor 43b is
One end sides of the second lower electrode 41b and the second upper electrode 42b are connected to each other. The second connection auxiliary conductor 44b connects the other end sides of the second lower electrode 41b and the second upper electrode 42b. The second input / output point 45b is located at one end of the second lower electrode 41b.

  According to the band-pass filter of this example having such a configuration, the first input / output coupling electrode 40a and the first resonance electrode 30a and the fourth resonance electrode 30d are maintained while maintaining the distance between them. The distance between the resonance electrode 30a and the fifth resonance electrode 31a can be increased. This can weaken the direct electromagnetic coupling between the first resonance electrode 30a and the fifth resonance electrode 31a. Therefore, the first input / output coupling electrode 40a, the first resonance electrode 30a, and the fourth resonance electrode 30a can be weakened. The electromagnetic field coupling with the resonance electrode 30d can be further strengthened.

  Similarly, according to the band-pass filter of this example, the fourth resonance electrode 30d is maintained while maintaining the distance between the second input / output coupling electrode 40b and the fourth resonance electrode 30d and the seventh resonance electrode 31c. And the seventh resonance electrode 31c can be widened. This can weaken the direct electromagnetic coupling between the fourth resonance electrode 30d and the seventh resonance electrode 31c, so that the second input / output coupling electrode 40b, the fourth resonance electrode 30d and the seventh resonance electrode 31c can be weakened. The electromagnetic field coupling with the resonance electrode 31c can be further strengthened.

  For this reason, according to the bandpass filter of this example, a bandpass filter having excellent pass characteristics that is flatter and has a lower loss can be obtained over the entire two wide passbands.

  The bandpass filter of this example includes resonance auxiliary electrodes 32a, 32b, 32c, and 32d. The resonance auxiliary electrodes 32a, 32b, 32c, and 32d are disposed in the interlayer A and the interlayer C of the multilayer body 10 so as to face the first annular ground electrode 23, and the first to fourth resonance electrodes, respectively. The other ends of 30a, 30b, 30c, and 30d are connected through a through conductor 50.

  According to the band-pass filter of this example having such a configuration, the first to fourth through the electrostatic capacitance generated between the resonance auxiliary electrodes 32a, 32b, 32c, 32d and the first annular ground electrode 23. Since the length of the resonant electrodes 30a, 30b, 30c, and 30d can be shortened, a smaller bandpass filter can be obtained.

  Further, the band pass filter of this example includes a first coupling auxiliary electrode 46a and a second coupling auxiliary electrode 46b. The first coupling auxiliary electrode 46a is disposed between the layers B of the multilayer body 10 so as to face the resonance auxiliary electrode 32a. The first coupling auxiliary electrode 46a has one end connected to the first input / output point 45a at one end of the first lower electrode 41a via the through conductor 50 and the other end at the other end. It is connected to the first input / output terminal electrode 60a through another through conductor 50. The second coupling auxiliary electrode 46b is disposed in the layer B of the laminate 10 so as to face the resonance auxiliary electrode 32d. The second coupling auxiliary electrode 46b has one end connected to the second input / output point 45b at one end of the second lower electrode 41b through the through conductor 50 and the other end at the other end. It is connected to the second input / output terminal electrode 60b through another through conductor 50.

According to the bandpass filter of this example having such a configuration, the joined body of the first resonance electrode 30a and the resonance auxiliary electrode 32a, and the junction of the first input / output coupling electrode 40a and the first coupling auxiliary electrode 46a. The body is generally broadside and strongly electromagnetically coupled to the interdigital type. Also, the joined body of the second resonance electrode 30b and the resonance auxiliary electrode 32d and the joined body of the second input / output coupling electrode 40b and the second coupling auxiliary electrode 46b are interdigital on the broad side as a whole. Strong electromagnetic coupling. As a result, it is possible to obtain a bandpass filter having excellent pass characteristics that is flatter and has a lower loss over the entire two wide passbands.
(Third example of embodiment)
FIG. 6 is an exploded perspective view schematically showing the band-pass filter of the third example of the embodiment of the present invention. In this example, only points different from the second example described above will be described, and the same components will be denoted by the same reference numerals, and redundant description will be omitted.

  As shown in FIG. 6, the bandpass filter of this example includes a first resonator coupling electrode 71 disposed between the layers D of the multilayer body 10 and a second resonator disposed between the layers E of the multilayer body 10. And a coupling electrode 72.

  The first resonator coupling electrode 71 includes a coupling portion 71a, a coupling portion 71b, and a coupling portion 71a and a connection portion 71c that connects one ends of the coupling portion 71b. The coupling portion 71a is disposed so as to face one end side of the first resonance electrode 30a, and the other end portion of the coupling portion 71a is connected to the first annular ground electrode 23 through the through conductor 50. . The coupling portion 71b is disposed so as to face one end side of the fourth resonance electrode 30d, and the other end portion of the coupling portion 71b is connected to the first annular ground electrode 23 via another through conductor 50. ing.

  The second resonator coupling electrode 72 includes a coupling portion 72a, a coupling portion 72b, and a coupling portion 72a that connects one ends of the coupling portion 72a and the coupling portion 72b. The coupling portion 72a is arranged to face one end side of the fifth resonance electrode 31a, and the coupling portion 72b is arranged to face one end side of the seventh resonance electrode 31c.

  According to the band-pass filter of this example having such a configuration, the first to fourth resonance electrodes 30a, 30b, 30b are provided between the first input / output coupling electrode 40a and the second input / output coupling electrode 40b. The electrical signal transmitted through the electromagnetic coupling between the adjacent resonators 30c and 30d and the electrical signal transmitted through the first resonator coupling electrode 71 cancel each other due to the phase difference between them. The attenuation pole can be formed in the vicinity of both sides of the first passband constituted by the first to fourth resonance electrodes 30a, 30b, 30c, 30d.

  Further, according to the bandpass filter of this example, the fifth to eighth resonance electrodes 31a, 31b, 31c, 35 are provided between the first input / output coupling electrode 40a and the second input / output coupling electrode 40b. An attenuation pole generated by canceling out an electrical signal transmitted via the electromagnetic coupling between adjacent resonators and an electrical signal transmitted via the second resonator coupling electrode 72 due to a phase difference between each other, It can be formed in the vicinity of both sides of the second pass band constituted by the fifth to eighth resonance electrodes 31a, 31b, 31c, 35.

  Further, according to the bandpass filter of this example, the first to fourth resonance electrodes 30a, 30b, 30c, 30d are provided between the first input / output coupling electrode 40a and the second input / output coupling electrode 40b. An electric signal obtained by combining the electric signal transmitted through the electromagnetic coupling between the adjacent resonators and the electric signal transmitted through the first resonator coupling electrode 71, and the fifth to eighth resonant electrodes An electric signal transmitted through the electromagnetic coupling between adjacent resonators 31a, 31b, 31c, and 35 and an electric signal obtained by combining the electric signal transmitted through the second resonator coupling electrode 72 It cancels out by mutual phase difference. This phenomenon occurs in a frequency region located between the attenuation pole generated near the high frequency side of the first passband and the attenuation pole generated near the low frequency side of the second passband. An attenuation pole can be formed.

  In this way, according to the bandpass filter of this example, three attenuation poles are generated in the frequency region located between the two passbands, so that the attenuation in the frequency region between the two passbands is sufficiently large. It is possible to obtain a bandpass filter having excellent secured pass characteristics.

(Fourth example of embodiment)
FIG. 7 is a block diagram schematically showing a wireless communication module 80 and a wireless communication device 85 of the fourth example of the embodiment of the present invention.

  The wireless communication module 80 of this example includes, for example, a baseband unit 81 that processes baseband signals, and an RF unit 82 that is connected to the baseband unit 81 and processes RF signals after modulation and before demodulation of the baseband signals. And. The RF unit 82 includes the band-pass filter 821 of the present invention described above. The band-pass filter 821 attenuates signals other than the communication band in the RF signal obtained by modulating the baseband signal or the received RF signal. Yes.

  Specifically, a baseband IC 811 is disposed in the baseband unit 81, and an RF IC 822 is disposed between the bandpass filter 821 and the baseband unit 81 in the RF unit 82. Note that another circuit may be interposed between these circuits. Then, by connecting the antenna 84 to the bandpass filter 821 of the wireless communication module 80, the wireless communication device 85 of this example that transmits and receives RF signals is configured.

  According to the wireless communication module 80 and the wireless communication device 85 of the present example having such a configuration, an attenuation pole is formed between the two passbands as well as low loss over the entire two wide passbands. By using the band-pass filter 821 of the present invention in which attenuation is sufficiently ensured, signals in two communication bands can be filtered. As a result, the attenuation of the communication signal can be reduced and the noise can be reduced, so that the reception sensitivity is improved and the amplification degree of the communication signal can be reduced, so that the power consumption in the amplifier circuit is reduced. Furthermore, since the filtering of the two communication bands can be performed by one filter, the circuit configuration can be simplified and the number of parts can be reduced. Therefore, it is possible to obtain a high-performance wireless communication module 80 and a wireless communication device 85 that are small in size, high in reception sensitivity, and low in power consumption.

(Modification)
The present invention is not limited to the first to fourth examples of the embodiment described above, and various modifications and improvements can be made without departing from the gist of the present invention.

  For example, in the first to third examples of the above-described embodiment, an example in which the first input / output terminal electrode 60a and the second input / output terminal electrode 60b are provided has been described. However, when a band-pass filter is formed in one region of the module substrate, the first input / output terminal electrode 60a and the second input / output terminal electrode 60b are not necessarily required. A wiring conductor from an external circuit may be directly connected to the first input / output coupling electrode 40a and the second input / output coupling electrode 40b. In this case, the connection points between the first input / output coupling electrode 40a and the second input / output coupling electrode 40b and the wiring conductor are the first input / output point 45a and the second input / output point 45b.

  In the first to third examples of the above-described embodiment, the first ground electrode 21 is disposed on the lower surface of the multilayer body 10 and the second ground electrode 22 is disposed on the upper surface of the multilayer body 10. However, for example, a dielectric layer may be further disposed below the first ground electrode 21, or a dielectric layer may be further disposed on the second ground electrode 22. Further, only one of the first ground electrode 21 and the second ground electrode 22 may be provided.

  Furthermore, in the first to third examples of the above-described embodiment, the example in which the bandpass filter is configured in one laminated body 10 is shown, but a plurality of laminated bodies laminated in the thickness direction. Alternatively, a band pass filter may be formed across the two.

  Furthermore, in the first to third examples of the above-described embodiment, the first input / output coupling electrode 40a and the second input / output coupling electrode 40b are arranged between the same layers of the stacked body 10, and the eighth In this example, the first portion 35a and the second portion 35b of the resonance electrode 35 are disposed between the same layers of the multilayer body 10. However, the first input / output coupling electrode 40a and the second input / output coupling electrode 40b are arranged between different layers as long as they are between the first layer and the second layer of the laminate 10. It doesn't matter. Similarly, the first portion 35 a and the second portion 35 b of the eighth resonance electrode 35 may be disposed between different layers of the multilayer body 10.

  Furthermore, although the bandpass filter used for UWB has been exemplified and described so far, it goes without saying that the bandpass filter of the present invention is effective in other applications.

  Next, a specific example of the bandpass filter of the present invention will be described.

  The bandpass filter of the second example of the embodiment of the present invention shown in FIG. 5, the bandpass filter of the third example of the embodiment of the present invention shown in FIG. 6, and the second example of the bandpass filter shown in FIG. The electrical characteristics of the bandpass filter of one comparative example and the bandpass filter of the second comparative example shown in FIG. 9 were calculated by simulation using a finite element method. As shown in FIG. 8, the band-pass filter of the first comparative example includes an eighth resonance electrode 35 in the structure shown in FIG. 5 and a sixth resonance electrode 31b between the second layer of the multilayer body 10 and the sixth resonance electrode 31b. 7 is replaced with a quarter-wave resonator 31d disposed between the seven resonance electrodes 31c. As shown in FIG. 9, the bandpass filter of the second comparative example includes the eighth resonance electrode 35 in the structure shown in FIG. 6, and the sixth resonance electrode 31 b and the second resonance electrode 31 b between the second layers of the multilayer body 10. And a structure in which both ends of the second resonator coupling electrode 72 are connected to the second annular ground electrode 24 through the through conductor 50. It was.

  In the simulation of the bandpass filter of the third example of the embodiment shown in FIG. 6, the plurality of first to fourth resonance electrodes 30a, 30b, 30c, 30d have a width of 0.15 mm and a length of 3.5 mm. A rectangular shape is used, and the distance between the first resonance electrode 30a and the second resonance electrode 30b and the distance between the third resonance electrode 30c and the fourth resonance electrode 30d are each 0.19 mm. The distance from the third resonance electrode 30c was 0.185 mm. The plurality of fifth to seventh resonance electrodes 31a, 31b, 31c have a rectangular shape with a width of 0.18 mm and a length of 2.54 mm, and the distance between the fifth resonance electrode 31a and the sixth resonance electrode 31b is 0.145 mm. It was. Regarding the eighth resonance electrode 35, the first portion 35a has a width of 0.21 mm and a length of 2.99 mm, the second portion 35b has a width of 0.15 mm and a length of 3.19 mm, and the connection portion 35c has a width of 0.257 mm and a length of 0.25. mm. The resonance auxiliary electrodes 32a and 32d each have a shape in which a rectangle having a width of 0.42 mm and a length of 0.53 mm and a rectangle having a width of 0.2 mm and a length of 0.5 mm are joined. The resonance auxiliary electrodes 32b and 32c each have a shape in which a rectangle having a width of 0.4 mm and a length of 0.52 mm and a rectangle having a width of 0.2 mm and a length of 0.5 mm are joined. The first lower electrode 41a and the second lower electrode 41b have a rectangular shape with a width of 0.15 mm and a length of 3.5 mm, and the first upper electrode 42a and the second upper electrode 42b have a width of 0.15. A rectangular shape with a length of 3.1 mm was used. The first connection conductor 43a and the first connection auxiliary conductor 44a were arranged at positions of 0.1 mm from both ends in the opposing region of the first lower electrode 41a and the first upper electrode 42a. The first connection conductor 43a and the first connection auxiliary conductor 44a were arranged at positions of 0.1 mm from both ends in the opposing region of the second lower electrode 41b and the second upper electrode 42b. The first coupling auxiliary electrode 46a and the second coupling auxiliary electrode 46b were rectangular with a width of 0.15 mm and a length of 1.2 mm. As for the first resonator coupling electrode 71, the coupling portions 71a and 71b each have a rectangular shape with a width of 0.1 mm and a length of 1.975 mm, and the connection portion 71c has a rectangular shape with a width of 0.1 mm and a length of 0.865 mm. It was. With respect to the second resonator coupling electrode 72, the coupling portions 72a and 72b have a rectangular shape with a width of 0.1 mm and a length of 0.6 mm, respectively, and the connection portion 72c has a rectangular shape with a width of 0.1 mm and a length of 0.762 mm. It was. Each of the first input / output terminal electrode 60a and the second input / output terminal electrode 60b was a square having a side of 0.3 mm, and the distance from the second ground electrode 22 was 0.2 mm. The outer shape of the first ground electrode 21, the second ground electrode 22, the first annular ground electrode 23 and the second annular ground electrode 24 is a rectangular shape having a width of 3 mm and a length of 5 mm. The opening of the electrode 23 has a rectangular shape with a width of 2.4 mm and a length of 3.65 mm, and the opening of the second annular ground electrode 24 has a rectangular shape with a width of 2.4 mm and a length of 2.69 mm. The overall shape of the bandpass filter was such that the width was 3 mm, the length was 5 mm, and the thickness was 0.975 mm, and the layers A and B were located in the center in the thickness direction. In the first to third layers and the layers A to E, the interval between adjacent layers (the interval between various electrodes arranged between adjacent layers) was set to 0.065 mm. The thickness of each electrode was 0.01 mm. The diameters of the first connection conductor 43a, the first connection auxiliary conductor 44a, the second connection conductor 43b, the second connection auxiliary conductor 44b, and the through conductor 50 were set to 0.1 mm. The relative dielectric constant of the dielectric layer 11 was 9.45.

  In the simulation of the bandpass filter of the second example of the embodiment shown in FIG. 5, the first example is used as it is from the bandpass filter of the third example of the embodiment shown in FIG. The resonator coupling electrode 71, the second resonator coupling electrode 72, and the through conductor 50 connected thereto are removed.

  The simulation results of the electrical characteristics of the bandpass filter of the second example, the bandpass filter of the third example, the bandpass filter of the first comparative example, and the bandpass filter of the second comparative example are shown in FIGS. 11, 12, and 13. Each graph shows the pass characteristic (S21) and reflection characteristic (S11) of the bandpass filter, with the horizontal axis representing frequency and the vertical axis representing attenuation.

  In the pass characteristic of the bandpass filter of the second example shown in FIG. 10, an attenuation pole is formed between the first passband and the second passband, but the first comparison shown in FIG. It can be seen that the pass characteristic of the example bandpass filter does not have the attenuation pole. Further, in the pass characteristic of the band-pass filter of the third example shown in FIG. 11, between the attenuation pole near the high frequency side of the first pass band and the attenuation pole near the low frequency side of the second pass band. Although another attenuation pole is formed, it can be seen that there is no attenuation pole in the pass characteristic of the bandpass filter of the second comparative example shown in FIG. Then, in the pass characteristics of the bandpass filters of the second example and the third example of the embodiment, the first passband and the second passband are higher than the pass characteristics of the bandpass filters of the first and second comparative examples. It can be seen that the amount of attenuation in the frequency region between the passbands increases. Thereby, the effectiveness of the present invention was confirmed.

10: Laminate
11: Dielectric layer
30a: first resonance electrode
30b: second resonant electrode
30c: third resonant electrode
30d: Fourth resonant electrode
31a: fifth resonance electrode
31b: sixth resonance electrode
31c: seventh resonance electrode
35: Eighth resonant electrode
35a: 1st part
35b: second part
35c: Connection part
40a: first input / output coupling electrode
40b: second input / output coupling electrode
45a: First input / output point
45b: Second input / output point
80: Wireless communication module
81: Baseband
82: RF section
821: Band pass filter
84: Antenna
85: Wireless communication equipment

Claims (3)

A laminate in which a plurality of dielectric layers are laminated;
A ground electrode disposed on at least one of the upper surface and the lower surface of the laminate;
Band-shaped first to thirteenth one to the other that are arranged side by side sequentially so that one end and the other end are staggered between the first layers of the laminate, each of which is grounded and functions as a quarter-wave resonator. A fourth resonant electrode;
Band-shaped fifth to seventh resonance electrodes, which are sequentially arranged side by side between second layers different from the first layer of the laminate, each having one end grounded and functioning as a quarter wavelength resonator. When,
A band-shaped first portion disposed in the vicinity of the sixth resonance electrode in parallel with the sixth resonance electrode and disposed in a layer opposite to the first layer with the second layer interposed therebetween; It comprises a band-shaped second portion that is disposed in parallel and close to the seventh resonance electrode and electromagnetically couples, and a connection portion that connects one ends of the first and second portions, and functions as a half-wave resonator An eighth resonant electrode;
Opposite to the region extending between the first layer and the second layer between the first layer and the second layer, the region extending over half the length of the first and fifth resonance electrodes. A first input / output coupling electrode for electromagnetic coupling;
Opposing to the region extending over the half of the length direction of the fourth and seventh resonance electrodes disposed between the first layer and the second layer of the laminate. A second input / output coupling electrode for electromagnetic coupling,
The one end of the first resonance electrode and the one end of the fifth resonance electrode are located on the same side, and the one end of the fourth resonance electrode and the one of the seventh resonance electrode One end is located on the same side, the one end of the fifth resonance electrode and the other end of the sixth resonance electrode are located on the same side, and the sixth resonance electrode One end and the other end of the first part are located on the same side, the one end of the seventh resonance electrode and the other end of the second part are located on the same side,
The first input / output coupling electrode includes a first input / output point to which an electric signal is input or output, and the first input / output point is in a length direction of the first input / output coupling electrode. , Located on the side farther from the one end of the first and fifth resonance electrodes than the center of the opposed portion to the first and fifth resonance electrodes,
The second input / output coupling electrode includes a second input / output point to which an electric signal is input or output, and the second input / output point is in a length direction of the second input / output coupling electrode. , Located on the side farther from the one end of the fourth and seventh resonance electrodes than the center of the opposed portion to the fourth and seventh resonance electrodes,
The pass characteristic has a first pass band formed by the first to fourth resonance electrodes and a second pass band formed by the fifth to eighth resonance electrodes. Bandpass filter.   A wireless communication module comprising the bandpass filter according to claim 1.   A wireless communication device comprising: an RF unit including the bandpass filter according to claim 1; a baseband unit connected to the RF unit; and an antenna connected to the RF unit.

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