JP5224908B2 - BANDPASS FILTER, RADIO COMMUNICATION MODULE AND RADIO COMMUNICATION DEVICE USING THE SAME - Google Patents

Description

  The present invention relates to a band-pass filter, a wireless communication module and a wireless communication device using the same, and in particular, a band-pass filter having two very wide pass bands that can be suitably used for UWB (Ultra Wide Band), and The present invention relates to a wireless communication module and a wireless communication device using the same.

  In recent years, UWB has attracted attention as a new communication means. UWB realizes large-capacity data transfer using a wide frequency band in a short distance of about 10 m.

  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).
“Ultra-wideband bandpass filter using microstrip-CPW broadside coupling structure” Proceedings of the March 2005 IEICE General Conference C-2-114 p.147 JP 2004-180032 A

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

  Therefore, the inventor of the present application proposed a bandpass filter having two very wide passbands that can cover the UWB low band filter and high band filter with a single filter in Japanese Patent Application 2007-222976. However, if the thickness is further reduced, the electromagnetic coupling between the resonator that forms the passband for the low band and the resonator that forms the passband for the high band becomes too strong, and good filter characteristics are obtained. Had the problem of becoming difficult.

  The present invention has been devised in view of such problems in the prior art, and its purpose is to have two very wide passbands and to obtain good filter characteristics even if the thickness is reduced. An object of the present invention is to provide a bandpass filter that can be used, and a wireless communication module and a wireless communication device using the same.

  The bandpass filter of the present invention includes a laminated body in which a plurality of dielectric layers are laminated, a first ground electrode disposed on a lower surface of the laminated body, a second ground electrode disposed on an upper surface, A plurality of strip-shaped first resonance electrodes arranged side by side so as to be electromagnetically coupled to each other between the first layers of the multilayer body and functioning as resonators each having one end grounded and resonating at a first frequency And a second layer that is arranged side by side so as to be electromagnetically coupled to each other in a second layer different from the first layer of the stacked body, and whose one end is grounded and is higher than the first frequency. A plurality of second resonance electrodes in a band shape that resonate at a frequency of the first and second layers disposed between the first layer and the second layer of the multilayer body. Half of the length direction of the first resonance electrode of the input stage among the resonance electrodes of one It is electromagnetically coupled to face the region extending over, and is disposed between the first input coupling electrode in the form of a strip having an electrical signal input point to which an electrical signal is input, and the third layer of the laminate, The first resonance electrode of the plurality of first resonance electrodes is electromagnetically coupled to face a region extending over half the length direction of the first resonance electrode in the output stage, and has an electric signal output point from which an electric signal is output. Of the plurality of second resonance electrodes disposed between the first output coupling electrode in the form of a band and the first interlayer and the second interlayer of the stacked body, A plurality of the second input coupling electrodes that are electromagnetically coupled to face the second resonant electrode, and the plurality of layers disposed between the first layer and the second layer of the multilayer body; Of the second resonance electrode of the first electrode in opposition to the second resonance electrode of the output stage The plurality of first resonance electrodes and the plurality of second resonance electrodes are arranged to be orthogonal to each other when viewed from the stacking direction of the stack, The second input coupling electrode is connected to the side farther from the electrical signal input point than the center in the length direction at the portion of the first input coupling electrode facing the first resonance electrode of the input stage. An electrical signal is input through one input coupling electrode, and the second output coupling electrode is arranged in a length direction at a portion of the first output coupling electrode facing the first resonance electrode of the output stage. It is connected to a side farther from the electrical signal output point than the center, and an electrical signal is output through the first output coupling electrode.

  In the bandpass filter of the present invention, in the above configuration, the second input coupling electrode is more than the center in the length direction of the first resonance electrode of the input stage when viewed from the stacking direction of the stacked body. The second output coupling electrode is disposed so as to intersect with the end side, and the one end side of the output stage from the center in the length direction of the first resonance electrode when viewed from the stacking direction of the stacked body. It is arranged so as to cross each other.

  Furthermore, the band-pass filter according to the present invention is configured such that, in each of the above configurations, the second input coupling electrode is disposed between the third layers and integrated with the first input coupling electrode, A coupling electrode is disposed between the third layers and integrated with the first output coupling electrode.

  Furthermore, the band-pass filter according to the present invention is configured such that, in each of the above-described configurations, the second input coupling electrode is disposed between layers closer to the second layer than the third layer, and the input-side connection conductor is interposed therebetween. The second input coupling electrode is connected to the first input coupling electrode, and the second output coupling electrode is disposed between layers closer to the second layer than the third layer, and is connected to the first input via an output-side connection conductor. It is connected to the output coupling electrode.

  A wireless communication module according to the present invention includes the band-pass filter according to the present invention having any one of the above-described configurations.

  A wireless communication device of the present invention includes an RF unit including the bandpass filter of the present invention having any one of the above-described configurations, a baseband unit connected to the RF unit, and an antenna connected to the RF unit. It is characterized by this.

  The electric signal input point of the first input coupling electrode is where an electric signal is input to the first input coupling electrode, and the electric signal output point of the first output coupling electrode is the first output coupling electrode. This is where an electrical signal is output from. Further, the side farther from the electrical signal input point than the center in the length direction of the portion of the first input coupling electrode facing the first resonant electrode in the input stage is opposed to the first resonant electrode in the input stage. When the first input coupling electrode is divided into two regions in the length direction with the center in the length direction in the section as a boundary, it means a region on the side not including the electric signal input point. Similarly, the side farther from the electrical signal output point than the center in the length direction in the portion of the first output coupling electrode facing the first resonant electrode in the output stage is the distance from the first resonant electrode in the output stage. When the first output coupling electrode is divided into two regions in the length direction with the center in the length direction in the facing portion as a boundary, it means a region on the side not including the electric signal output point.

  According to the bandpass filter of the present invention, since the plurality of first resonance electrodes and the plurality of second resonance electrodes are arranged so as to be orthogonal to each other when viewed from the stacking direction of the stack, Even when the plurality of first resonance electrodes are thin and the plurality of second resonance electrodes are close to each other, the electromagnetic coupling generated between the plurality of first resonance electrodes and the plurality of second resonance electrodes is reduced. Since the electromagnetic field coupling between the plurality of first resonance electrodes and the plurality of second resonance electrodes becomes excessively strong, it is possible to prevent the deterioration of the pass characteristics in the pass band. .

  Here, in order to obtain a flat and low-loss pass characteristic over a very wide pass band exceeding 10% in the specific band, the electromagnetic coupling between the resonance electrode and the input coupling electrode of the input stage and the output stage It is necessary to make the electromagnetic field coupling between the resonance electrode and the output coupling electrode very strong. However, the first input coupling electrode that is electromagnetically coupled to face the first resonance electrode of the input stage and the second input coupling electrode that is electromagnetically coupled to face the second resonance electrode of the input stage are simply used. And a first output coupling electrode that is electromagnetically coupled opposite the first resonance electrode of the output stage and a second output coupling electrode that is electromagnetically coupled opposite the second resonance electrode of the output stage Is not sufficient, the electromagnetic coupling between the first resonance electrode and the first input coupling electrode in the input stage and the electromagnetic coupling between the first resonance electrode and the first output coupling electrode in the output stage are insufficient. As a result, it has been found by the inventor of the present application that good pass characteristics cannot be obtained at all in the pass band formed by the plurality of first resonance electrodes.

  Therefore, as a result of various studies, the inventor of the present application has provided an electric signal input point where an electric signal is input to the first input coupling electrode, and the second input coupling electrode is connected to the first input coupling electrode. The electric signal is input via the first input coupling electrode, and the position where the second input coupling electrode is connected to the first input coupling electrode is set to the input stage of the first input coupling electrode. Electromagnetic field coupling between the first input coupling electrode and the first resonance electrode in the input stage is made farther from the electric signal input point than the center in the length direction at the portion facing the first resonance electrode. Has been found to be sufficiently strong. The reason why such an effect is obtained is that the second input coupling electrode is farther from the electric signal input point than the center in the length direction at the portion of the input stage of the first input coupling electrode facing the first resonance electrode. By connecting the first input coupling electrode to the first resonance electrode of the input stage of the input stage of the first input coupling electrode, a sufficient amount of current flows through the portion of the first input coupling electrode facing the first resonance electrode. It may be because it can be secured.

  Similarly, an electrical signal output point at which an electrical signal is output is provided on the first output coupling electrode, and the second output coupling electrode is connected to the first output coupling electrode and electrically connected via the first output coupling electrode. The position where the second output coupling electrode is connected to the first output coupling electrode is set to the length of the output stage of the first output coupling electrode at the portion facing the first resonance electrode. By making the side farther from the electrical signal output point than the center in the vertical direction, the electromagnetic field coupling between the first output coupling electrode and the first resonance electrode of the output stage can be made sufficiently strong.

  That is, according to the band-pass filter of the present invention, the first input coupling electrode is opposed to the region over the half of the length direction of the first resonance electrode of the input stage via the dielectric layer so as to be electromagnetically coupled. The first output coupling electrode is electromagnetically coupled to the region over the half of the length direction of the first resonance electrode of the output stage via the dielectric layer, and the second input coupling electrode is The first input coupling electrode is connected to the side farther from the electric signal input point than the center in the length direction at the portion of the input stage facing the first resonance electrode, and the electric signal is transmitted through the first input coupling electrode. The second output coupling electrode is connected to a side farther from the electrical signal output point than the center in the length direction at the portion of the output stage of the first output coupling electrode facing the first resonance electrode. Since the electric signal is output through the output coupling electrode of the first input coupling, The electromagnetic field coupling between the electrode and the first resonance electrode of the input stage and the electromagnetic field coupling between the first output coupling electrode and the first resonance electrode of the output stage can be made sufficiently strong. A bandpass filter having excellent pass characteristics with flatness and low loss over the entire wide passband formed by the first resonance electrode can be obtained.

  Further, according to the bandpass filter of the present invention, the second input coupling electrode intersects with one end side from the center in the length direction of the first resonance electrode of the input stage when viewed from the stacking direction of the stacked body. And when the second output coupling electrode is arranged so as to cross one end side from the center in the length direction of the first resonance electrode of the output stage when viewed from the stacking direction of the stacked body, The coupling by the electric field between the second input coupling electrode and the first resonant electrode of the input stage is reduced, and the coupling by the electric field between the second output coupling electrode and the first resonant electrode of the output stage is reduced. Therefore, unnecessary electromagnetic field coupling between the second input coupling electrode and the first resonance electrode of the input stage and between the second output coupling electrode and the first resonance electrode of the output stage is large. It is possible to prevent the deterioration of filter characteristics due to becoming

  Further, according to the bandpass filter of the present invention, the second input coupling electrode is disposed between the third layers and integrated with the first input coupling electrode, and the second output coupling electrode is the third interlayer. When the first output coupling electrode is integrated with the first output coupling electrode, the connection conductor connecting the first input coupling electrode and the second input coupling electrode, and the first output coupling electrode and the second output coupling electrode are connected. Therefore, a thin band-pass filter having a simple structure can be obtained while loss due to the connection conductor can be eliminated.

  Still further, according to the bandpass filter of the present invention, the second input coupling electrode is disposed between the layers closer to the second layer than the third layer, and the first input coupling electrode is interposed via the input side connection conductor. And maintaining the distance between the first input coupling electrode and the first resonance electrode of the input stage and the distance between the second input coupling electrode and the second resonance electrode of the input stage, Since the distance between the first resonant electrode of the input stage and the second resonant electrode of the input stage can be increased, electromagnetic coupling between the first input coupling electrode and the first resonant electrode of the input stage and Decreasing electromagnetic coupling between the first resonant electrode in the input stage and the second resonant electrode in the input stage without weakening the electromagnetic coupling between the second input coupled electrode and the second resonant electrode in the input stage. By which the first input coupling electrode and the first resonant electrode of the input stage Electromagnetic coupling between the second resonance electrode of the input stage and the magnetic coupling and a second input coupling electrode can be further strengthened. Similarly, when the second output coupling electrode is disposed between layers closer to the second layer than the third layer and connected to the first output coupling electrode via the output-side connection conductor, While maintaining the distance between the output coupling electrode and the first resonance electrode of the output stage and the distance between the second output coupling electrode and the second resonance electrode of the output stage, the first resonance electrode and the output of the output stage are maintained. Since the distance between the second resonant electrode of the stage can be increased, electromagnetic coupling between the first output coupling electrode and the first resonant electrode of the output stage, and between the second output coupling electrode and the output stage Without weakening the electromagnetic coupling with the second resonant electrode, it is possible to weaken the electromagnetic coupling between the first resonant electrode at the output stage and the second resonant electrode at the output stage, whereby the first output Electromagnetic field coupling between the coupling electrode and the first resonance electrode of the output stage, and a second output coupling electrode and the output It can further strengthen the electromagnetic coupling between the second resonance electrode.

  According to the wireless communication module of the present invention and the wireless communication device of the present invention, by using the band-pass filter of the present invention with a small loss of the signal passing over the entire communication band for filtering the transmission signal and the reception signal, Since the attenuation of the reception signal and the transmission signal passing through the band pass filter is reduced, the reception sensitivity is improved, and the amplification degree of the transmission signal and the reception signal can be reduced. Therefore, a high-performance wireless communication module and wireless communication device with high reception sensitivity and low power consumption can be obtained. Furthermore, by using the band-pass filter of the present invention that can cover two communication bands with one filter and obtain good filter characteristics even if it is thin, a wireless communication module that is small in size and low in manufacturing cost A wireless communication device can be obtained.

  Hereinafter, a bandpass filter of the present invention, a wireless communication module and a wireless communication device using the same will be described in detail with reference to the accompanying drawings.

(First example of embodiment)
FIG. 1 is an external perspective view schematically showing an example of an embodiment of a bandpass filter of the present invention. FIG. 2 is a schematic exploded perspective view of the example of the bandpass filter shown in FIG. FIG. 3 is a plan view schematically showing upper and lower surfaces and layers of the example of the bandpass filter shown in FIG. FIG. 4 is a cross-sectional view taken along the line PP ′ of the example of the bandpass filter shown in FIG.

  As shown in FIGS. 1 to 4, the bandpass filter of this example includes a laminated body 10 in which a plurality of dielectric layers 11 are laminated, and a first ground that is disposed on the lower surface of the laminated body 10 and is grounded. The electrode 21 and the second ground electrode 22 arranged on the upper surface and grounded, and arranged side by side so as to be electromagnetically coupled to each other between the first layers of the laminate 10, are grounded at one end respectively. Electromagnetic field coupling between a plurality of strip-shaped first resonance electrodes 30a, 30b, 30c, and 30d that function as a resonator that resonates at one frequency and a second layer that is different from the first layer of the laminate 10 A plurality of strip-shaped second resonance electrodes 31a, 31b, 31c, and 31d, which are arranged side by side, each of which is grounded at one end and resonates at a second frequency higher than the first frequency. Yes.

  The band-pass filter of this example is the length of the first resonance electrode 30a in the input stage, which is disposed between the first and second layers of the multilayer body 10. A band-shaped first input coupling electrode 40a having an electric signal input point 45a to which an electric signal is inputted while being opposed to a region extending over half of the direction, and an output stage first resonance electrode 30b A strip-shaped first output coupling electrode 40b having an electric signal output point 45b that is electromagnetically coupled to an area extending over half of the length direction and outputs an electric signal, and a second resonance electrode in the input stage A second input coupling electrode 41a that is electromagnetically coupled to face 31a, and a second output coupling electrode 41b that is electromagnetically coupled to face the second resonance electrode 31b of the output stage are provided. The first input coupling electrode 40a and the second input coupling electrode 41a are integrated, and the first output coupling electrode 40b and the second output coupling electrode 41b are integrated.

  Further, the bandpass filter of this example is formed in an annular shape so as to surround the plurality of first resonance electrodes 30a, 30b, 30c, and 30d between the first layers of the multilayer body 10, and the plurality of first resonances. A first annular ground electrode 23 connected to the ground potential, to which one end of the electrodes 30a, 30b, 30c, 30d is connected, and a plurality of second resonance electrodes 31a, 31b, 31c, 31d between the second layers. And a second annular ground electrode 24 connected to the ground potential, to which one end of a plurality of second resonance electrodes 31a, 31b, 31c, 31d is connected. Yes.

  Furthermore, in the band-pass filter of this example, the first input coupling electrode 40a is connected to the input terminal electrode 60a disposed on the upper surface of the multilayer body 10 through the through conductor 50 penetrating the dielectric layer 11. The first output coupling electrode 40b is connected to an output terminal electrode 60b disposed on the upper surface of the multilayer body 10 through a through conductor 50 penetrating the dielectric layer 11. Therefore, the connection point between the first input coupling electrode 40a and the through conductor 50 is an electric signal input point 45a in the first input coupling electrode 40a, and the connection between the first output coupling electrode 40b and the through conductor 50 is achieved. The point is an electric signal output point 45b in the first output coupling electrode 40b.

  The band-pass filter of this example having such a configuration has a first input coupling when an electric signal from an external circuit is input to the first input coupling electrode 40a via the input terminal electrode 60a and the through conductor 50. By exciting the first resonant electrode 30a in the input stage that is electromagnetically coupled to the electrode 40a, the plurality of first resonant electrodes 30a, 30b, 30c, and 30d that are electromagnetically coupled to each other resonate, and the output stage An electric signal is output from the first output coupling electrode 40b electromagnetically coupled to the first resonance electrode 30b to the external circuit via the through conductor 50 and the output terminal electrode 60b. At this time, since a signal in the first frequency band including the first frequency at which the plurality of first resonance electrodes 30a, 30b, 30c, and 30d resonate selectively passes, a first pass band is thereby formed. The At the same time, since the electric signal from the external circuit is also input to the second input coupling electrode 41a via the input terminal electrode 60a, the through conductor 50 and the first input coupling electrode 40a, the second input coupling electrode When the second resonant electrode 31a of the input stage that is electromagnetically coupled to 41a is excited, the plurality of second resonant electrodes 31a, 31b, 31c, and 31d that are electromagnetically coupled to each other resonate, and the second resonant electrode 31a of the output stage is resonated. An electric signal is output from the second output coupling electrode 41b electromagnetically coupled to the second resonance electrode 31b to the external circuit via the first output coupling electrode 40b, the through conductor 50, and the output terminal electrode 60b. At this time, since a signal in the second frequency band including the second frequency at which the plurality of second resonance electrodes 31a, 31b, 31c, 31d resonate selectively passes, a second pass band is thereby formed. Is done. In this way, the bandpass filter of this example functions as a bandpass filter having two passbands having different frequencies.

  In the band-pass filter of this example, the plurality of strip-shaped first resonance electrodes 30a, 30b, 30c, and 30d have an electrical length set to about ¼ of the wavelength at the first frequency, It functions as a quarter wavelength resonator by being connected to the first annular ground electrode 23 and grounded. Similarly, the plurality of strip-like second resonance electrodes 31a, 31b, 31c, and 31d are set to have an electrical length of about ¼ of the wavelength at the second frequency, and one end of each of them is the second annular ground. By being connected to the electrode 24 and grounded, it functions as a quarter wavelength resonator. The plurality of first resonance electrodes 30a, 30b, 30c, and 30d are arranged side by side between the first layers of the laminated body 10 so that the respective one ends thereof are staggered and electromagnetically coupled to the interdigital type. The plurality of second resonance electrodes 31a, 31b, 31c, and 31d are arranged side by side between the second layers of the multilayer body 10 so that the respective one ends thereof are staggered and electromagnetically coupled to the interdigital type. Yes. By the interdigital type strong coupling that combines the coupling by the magnetic field and the coupling by the electric field, the resonance frequency interval of each resonance mode that forms the pass band can be increased to a very wide pass bandwidth exceeding 10% in the specific band. It becomes easy to make it reasonable to obtain. When the distance between the resonant electrodes arranged side by side is smaller, stronger coupling can be obtained. However, if the distance is reduced, manufacturing becomes difficult. For example, the distance is set to about 0.05 to 0.5 mm.

  In the bandpass filter of this example, the first input coupling electrode 40a and the first output coupling electrode 40b have the same dimensions as the first resonance electrode 30a in the input stage and the first resonance electrode 30b in the output stage. It is preferable to set the degree. Further, the distance between the first input coupling electrode 40a and the first output coupling electrode 40b and the first resonance electrode 30a of the input stage and the first resonance electrode 30b of the output stage, and the second input coupling electrode 41a and If the distance between the second output coupling electrode 41b, the second resonance electrode 31a at the input stage, and the second resonance electrode 31b at the output stage is reduced, the coupling becomes stronger but difficult to manufacture. It is set to about 0.5 mm.

  Further, in the bandpass filter of this example, the second input coupling electrode 41a is band-shaped and is disposed so as to oppose the second resonance electrode 31a of the input stage, and the first input coupling electrode 40a. Is integrated with the first input coupling electrode 40a. Therefore, a portion where the first input coupling electrode 40a and the second input coupling electrode 41a intersect functions as the first input coupling electrode 40a and also functions as the second input coupling electrode 41a. The second output coupling electrode 41b has a strip shape, is disposed so as to face the second resonance electrode 31b in the output stage, and intersects with the first output coupling electrode 40b. It is integrated with the output coupling electrode 40b. Therefore, the portion where the first output coupling electrode 40b and the second output coupling electrode 41b intersect functions as the first output coupling electrode 40b and also functions as the second output coupling electrode 41b. The lengths of the second input coupling electrode 41a and the second output coupling electrode 41b are appropriately set according to the required coupling amount.

  According to the bandpass filter of this example, the plurality of first resonance electrodes 30a, 30b, 30c, 30d and the plurality of second resonance electrodes 31a, 31b, 31c, 31d are viewed from the stacking direction of the stacked body 10. Since the stacked body 10 is thinly arranged, the plurality of first resonance electrodes 30a, 30b, 30c, 30d and the plurality of second resonance electrodes 31a, 31b, 31c, 31d are arranged. Even when they are close to each other, electromagnetic field coupling generated between the plurality of first resonance electrodes 30a, 30b, 30c, 30d and the plurality of second resonance electrodes 31a, 31b, 31c, 31d can be minimized. Since the electromagnetic field coupling between the plurality of first resonance electrodes 30a, 30b, 30c, and 30d and the plurality of second resonance electrodes 31a, 31b, 31c, and 31d becomes excessively strong, Can be prevented.

  Further, according to the bandpass filter of the present example, the first input coupling electrode 40a is electromagnetically opposed to the entire region in the length direction of the first resonance electrode 30a of the input stage via the dielectric layer 11. The first output coupling electrode 40b is electromagnetically coupled to face the entire region in the length direction of the first resonance electrode 30b of the output stage via the dielectric layer 11, and is coupled to the field. The input coupling electrode 41a is connected to the side farther from the electrical signal input point 45a than the center in the length direction at the portion of the input stage of the first input coupling electrode 40a facing the first resonance electrode 30a, and is connected to the first input electrode. An electric signal is input through the coupling electrode 40a, and the second output coupling electrode 41b is more electrically than the center in the length direction at the portion of the output stage of the first output coupling electrode 40b facing the first resonance electrode 30b. The electric signal is connected to the side far from the signal output point 45b and connected via the first output coupling electrode 40b. Is output, the electromagnetic coupling between the first input coupling electrode 40a and the first resonance electrode 30a at the input stage and the electromagnetic coupling between the first output coupling electrode 40b and the first resonance electrode 30b at the output stage. Since field coupling can be made sufficiently strong, it has excellent pass characteristics with flatness and low loss over the entire wide pass band formed by the plurality of first resonance electrodes 30a, 30b, 30c, 30d. A bandpass filter having the same can be obtained.

  Furthermore, according to the bandpass filter of this example, the electric signal input point 45a is located at the end in the length direction of the first input coupling electrode 40a facing the first resonance electrode 30a in the input stage. Since the electric signal output point 45b is located at the end of the first output coupling electrode 40b facing the first resonance electrode 30b in the length direction, the first input coupling electrode 40b The electromagnetic coupling between 40a and the first resonance electrode 30a in the input stage and the electromagnetic coupling between the first output coupling electrode 40b and the first resonance electrode 30b in the output stage can be further strengthened.

  Still further, according to the bandpass filter of this example, the electric signal input point 45a is located at the input stage more than the center in the length direction at the portion of the input stage of the first input coupling electrode 40a facing the first resonant electrode 30a. The first resonance electrode 30a is located far from one end (grounding end) of the first resonance electrode 30a, and the electric signal output point 45b is a portion of the output stage of the first output coupling electrode 40b facing the first resonance electrode 30b. Is located farther from one end (ground end) of the first resonance electrode 30b of the output stage than the center in the length direction of the first input coupling electrode 40a and the first resonance of the input stage. Since the electrode 30a is electromagnetically coupled to the interdigital type, and the first output coupling electrode 40b and the first resonance electrode 30b of the output stage are electromagnetically coupled to the interdigital type, the first input coupling electrode 40a Electromagnetic field coupling and first output coupling with the first resonant electrode 30a of the input stage The electromagnetic field coupling between the electrode 40b and the first resonance electrode 30b of the output stage can be further strengthened.

  Furthermore, according to the band-pass filter of this example, the second input coupling electrode 41a is opposed to one end (grounding end) side from the center in the length direction of the first resonance electrode 30a of the input stage. Since the second output coupling electrode 41b is disposed so as to face one end (grounding end) side from the center in the length direction of the first resonance electrode 30b of the output stage, the second output coupling electrode 41b The coupling due to the electric field between the input coupling electrode 41a and the first resonance electrode 30a at the input stage is reduced, and the coupling between the second output coupling electrode 41b and the first resonance electrode 30b at the output stage by the electric field is reduced. Since it can be made smaller, it is unnecessary between the second input coupling electrode 41a and the first resonance electrode 30a of the input stage and between the second output coupling electrode 41b and the first resonance electrode 30b of the output stage. Prevents deterioration of filter characteristics due to large electromagnetic field coupling It is possible.

  Still further, according to the bandpass filter of this example, the second input coupling electrode 41a is disposed between the third layers and integrated with the first input coupling electrode 40a, and the second output coupling electrode 41b is Since it is disposed between the third layers and integrated with the first output coupling electrode 40b, the connection conductor and the first output coupling electrode for connecting the first input coupling electrode 40a and the second input coupling electrode 41a Since a connection conductor for connecting 40b and the second output coupling electrode 41b is not necessary, loss due to the connection conductor can be eliminated, and a thin bandpass filter having a simple structure can be obtained.

  Furthermore, according to the bandpass filter of this example, the one end of the first resonance electrode 30a in the input stage and the one end of the first resonance electrode 30b in the output stage are alternately arranged. Since one end of the second resonance electrode 31a in the input stage and one end of the second resonance electrode 31b in the output stage are alternately arranged, the first input coupling electrode 40a and the input stage A structure and a circuit configuration in which electromagnetic field coupling with the first resonance electrode 30a and electromagnetic coupling between the first output coupling electrode 40b and the first resonance electrode 30b in the output stage are sufficiently strong and symmetrical. The provided band pass filter can be obtained.

(Second example of embodiment)
FIG. 5 is an external perspective view schematically showing another example of the embodiment of the band-pass filter of the present invention. 6 is a schematic exploded perspective view of the example of the bandpass filter shown in FIG. FIG. 7 is a plan view schematically showing upper and lower surfaces and layers of the example of the bandpass filter shown in FIG. FIG. 8 is a cross-sectional view taken along the line QQ ′ of the example of the bandpass filter shown in FIG. 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 FIGS. 5 to 8, the first resonance electrodes 30a and 30c are electromagnetically coupled to each other in a comb-line type, and the first resonance electrodes 30b and 30d are mutually connected. The comb line type is electromagnetically coupled, the second resonance electrodes 31a and 31c are electromagnetically coupled to each other, and the second resonance electrodes 31b and 31d are electromagnetically coupled to each other in the comb line type. ing. The first resonance electrodes 30c and 30d are electromagnetically coupled to each other in an interdigital manner, and the second resonance electrodes 31c and 31d are electromagnetically coupled to each other in an interdigital manner.

  In the band-pass filter of this example, the region facing the first annular ground electrode 23 and the first resonant electrode 30a, in the interlayer A located between the lower surface of the multilayer body 10 and the first layer, 30 b, 30 c, 30 d and a region opposite to the first resonance electrode 30 a, 30 b, 30 c, 30 d, the region opposite the first resonance electrode is formed by a through conductor 50 penetrating the dielectric layer 11. The first resonance auxiliary electrodes 32a, 32b, 32c, and 32d connected to the other ends of 30a, 30b, 30c, and 30d are disposed corresponding to the first resonance electrodes 30a, 30b, 30c, and 30d, respectively. Has been. Further, a region facing the second annular ground electrode 24 and a region facing the second resonance electrodes 31a, 31b, 31c, and 31d are provided in the interlayer B located between the upper surface of the laminate 10 and the second layer. The region opposite to the second resonance electrodes 31a, 31b, 31c, 31d is the other of the second resonance electrodes 31a, 31b, 31c, 31d by the through conductor 50 penetrating the dielectric layer 11. The second resonance auxiliary electrodes 33a, 33b, 33c, and 33d connected to the end sides are disposed corresponding to the second resonance electrodes 31a, 31b, 31c, and 31d, respectively.

  According to the bandpass filter of this example having such a structure, the capacitance generated between the first resonance auxiliary electrodes 32a, 32b, 32c, 32d and the first annular ground electrode 23 is the first. Since it is added to the capacitance generated between the resonant electrodes 30a, 30b, 30c, and 30d and the ground potential, the length of the first resonant electrodes 30a, 30b, 30c, and 30d can be shortened, and similarly In addition, since the length of the second resonance electrodes 31a, 31b, 31c, and 31d can be shortened by the second resonance auxiliary electrodes 33a, 33b, 33c, and 33d, a smaller band-pass filter can be obtained.

The area of the opposing portion of the first resonance auxiliary electrode 32a, 32b, 32c, 32d and the first annular ground electrode 23 and the second resonance auxiliary electrode 33a, 33b, 33c, 33d and the second annular ground electrode The area of the portion facing 24 is set to, for example, about 0.01 to ³ mm ² according to the required capacitance. Further, the distance between the first resonance auxiliary electrode 32a, 32b, 32c, 32d and the first annular ground electrode 23, and the distance between the second resonance auxiliary electrode 33a, 33b, 33c, 33d and the second annular ground electrode 24. The smaller the interval, the larger the capacitance can be generated, but the manufacturing becomes difficult. For example, the interval is set to about 0.01 to 0.5 mm.

(Third example of embodiment)
FIG. 9 is an external perspective view schematically showing still another example of the embodiment of the band-pass filter of the present invention. FIG. 10 is a schematic exploded perspective view of the example of the bandpass filter shown in FIG. FIG. 11 is a plan view schematically showing the upper and lower surfaces and the layers of the example of the bandpass filter shown in FIG. 12 is a cross-sectional view taken along the line RR ′ of the example of the bandpass filter shown in FIG. 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.

  As shown in FIGS. 9 to 12, the band-pass filter of the present example includes a region facing the first annular ground electrode 23 in the layer A located between the lower surface of the multilayer body 10 and the first layer. The first resonant electrode 30c is arranged by a through conductor 50 which is disposed so as to have a region facing the first resonant electrodes 30c and 30d, and the region facing the first resonant electrodes 30c and 30d penetrates the dielectric layer 11. , 30d are respectively connected to the other end sides of the resonance auxiliary electrodes 32c, 32d corresponding to the first resonance electrodes 30c, 30d. Further, it is disposed between the third layer of the laminate 10 so as to have a region facing the first annular ground electrode 23 and a region facing the first resonance electrodes 30a and 30b, and the first resonance electrode 30a. , 30b are connected to the other ends of the first resonance electrodes 30a, 30b by through conductors 50 penetrating the dielectric layer 11, and first resonance auxiliary electrodes 32a, 32b are connected to the first resonance. The electrodes 30a and 30b are arranged corresponding to the electrodes 30a and 30b, respectively.

  In addition, the bandpass filter of this example is opposed to the region facing the first resonance auxiliary electrode 32a and the first input coupling electrode 40a in the layer C located between the second layer and the third layer. A region facing the first input coupling electrode 40a is connected to the first input coupling electrode 40a by the through conductor 50, and the region facing the first resonance auxiliary electrode 32a. Includes an input coupling auxiliary electrode 46a connected to the input terminal electrode 60a by a through conductor 50. Similarly, the interlayer C is disposed so as to have a region facing the first resonance auxiliary electrode 32b and a region facing the first output coupling electrode 40b, and is opposed to the first output coupling electrode 40b. An output coupling auxiliary electrode 46b having a region connected to the first output coupling electrode 40b by a through conductor 50 and a region facing the first resonance auxiliary electrode 32b connected to the output terminal electrode 60b through the through conductor 50 is provided. ing.

  Further, in the bandpass filter of this example, the second input coupling electrode 41a and the second output coupling electrode 41b are arranged in the interlayer D located between the second interlayer and the interlayer C, and the second The input coupling electrode 41a is connected to the first input coupling electrode 40a via the input side connection conductor 43a, and the second output coupling electrode 41b is connected to the first output coupling electrode 40b via the output side connection conductor 43b. It is connected to the.

  According to the bandpass filter of this example having such a structure, the capacitance generated between the first resonance auxiliary electrodes 32a, 32b, 32c, 32d and the first annular ground electrode 23 is the first. Since it is added to the capacitance generated between the resonant electrodes 30a, 30b, 30c, and 30d and the ground potential, the length of the first resonant electrodes 30a, 30b, 30c, and 30d can be shortened. The bandpass filter can be obtained.

  Further, according to the bandpass filter of this example, the electromagnetic coupling between the input coupling auxiliary electrode 46a and the first resonance auxiliary electrode 32a is performed between the first input coupling electrode 40a and the first resonance electrode 30a in the input stage. In addition to the electromagnetic field coupling, the electromagnetic field coupling between the output coupling auxiliary electrode 46b and the first resonance auxiliary electrode 32b is the electromagnetic field between the first output coupling electrode 40b and the first resonance electrode 30b in the output stage. Since it is added to the coupling, the electromagnetic coupling between the first input coupling electrode 40a and the first resonance electrode 30a in the input stage and the electromagnetic coupling between the first output coupling electrode 40b and the first resonance electrode 30b in the output stage. Since the field coupling is further strengthened, even in a pass band formed by the plurality of first resonance electrodes 30a, 30b, 30c, and 30d, even if the pass band is very wide, it is between the resonance frequencies of the respective resonance modes. Further increase in insertion loss at the located frequency And may be over the entire wide pass band to obtain a low-loss pass characteristic than flatter.

  Furthermore, according to the bandpass filter of this example, the second input coupling electrode 41a is arranged in the interlayer D which is closer to the second layer than the third layer. The first resonance electrode 30a and the input stage of the input stage are maintained while maintaining the distance between the first resonance electrode 30a of the stage and the distance between the second input coupling electrode 41a and the second resonance electrode 31a of the input stage. Since the distance between the first resonance electrode 31a and the second resonance electrode 31a can be increased, the electromagnetic coupling between the first input coupling electrode 40a and the first resonance electrode 30a in the input stage and the second input coupling electrode 41a Without weakening the electromagnetic coupling with the second resonant electrode 31a in the input stage, the electromagnetic coupling between the first resonant electrode 30a in the input stage and the second resonant electrode 31a in the input stage can be weakened. The electromagnetic coupling between the first input coupling electrode 40a and the first resonant electrode 30a of the input stage by Preliminary and second input coupling electrode 41a of the electromagnetic coupling between the second resonance electrode 31a of the input stage can be further strengthened.

  Further, according to the bandpass filter of this example, the second output coupling electrode 41b is disposed in the interlayer D which is closer to the second layer than the third layer, so that the first output coupling electrode 40b and the output The first resonance electrode 30b and the output stage of the output stage are maintained while maintaining the distance between the first resonance electrode 30b of the stage and the distance between the second output coupling electrode 41b and the second resonance electrode 31b of the output stage. Since the distance between the first resonance electrode 31b and the second resonance electrode 31b can be increased, the electromagnetic coupling between the first output coupling electrode 40b and the first resonance electrode 30b in the output stage and the second output coupling electrode 41b Without weakening the electromagnetic coupling with the second resonant electrode 31b at the output stage, the electromagnetic coupling between the first resonant electrode 30b at the output stage and the second resonant electrode 31b at the output stage can be weakened. The electromagnetic coupling between the first output coupling electrode 40b and the first resonance electrode 30b of the output stage is The electromagnetic coupling of beauty and the second output coupling electrode 41b and the second resonance electrode 31b of the output stage can be further strengthened.

  The widths of the input coupling auxiliary electrode 46a and the output coupling auxiliary electrode 46b are set, for example, to be approximately the same as those of the first input coupling electrode 40a and the first output coupling electrode 40b, and the input coupling auxiliary electrode 46a and the output coupling auxiliary electrode 46b. The length of the electrode 46b is set slightly longer than the length of the first resonance auxiliary electrodes 32a and 32b, for example. The spacing between the input coupling auxiliary electrode 46a and the output coupling auxiliary electrode 46b and the first resonance auxiliary electrode 32a, 32b is preferably small in terms of causing strong coupling, but becomes difficult in manufacturing. It is set to about 0.5 mm.

(Fourth example of embodiment)
FIG. 13 is a block diagram showing a configuration example of the wireless communication module 80 and the wireless communication device 85 using the bandpass filter of the present invention.

  The wireless communication module 80 of the present invention 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 bandpass filter 821 of the present invention described above, and an RF signal obtained by modulating the baseband signal or a signal other than the communication band in the received RF signal is attenuated by the bandpass filter 821. 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 the present invention 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, the present invention has a small loss of signals that pass through the input impedance being well matched over the entire frequency band used for communication. By using the bandpass filter 821 for filtering the transmission signal and the reception signal, attenuation of the reception signal and the transmission signal passing through the bandpass filter 821 is reduced, so that the reception sensitivity is improved, and the transmission signal and the reception signal are improved. Therefore, the power consumption in the amplifier circuit is reduced. Therefore, a high-performance wireless communication module 80 and a wireless communication device 85 with high reception sensitivity and low power consumption can be obtained.

In the band-pass filter of the present invention, 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 bandpass filter of the present invention can be manufactured, for example, as follows. 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 or the like, and a conductive paste containing a conductor such as Ag, Ag-Pd, Au, Cu is filled and the ceramic 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 a conductive paste are laminated, pressed using a hot press device, and fired at a peak temperature of about 800 ° C. to 1050 ° C.

(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 input terminal electrode 60a and the output terminal electrode 60b are provided is shown. However, a band-pass filter is formed in one region in the module substrate. In such a case, the input terminal electrode 60a and the output terminal electrode 60b are not necessarily required, and the wiring conductor from the external circuit in the module substrate is directly connected to the first input coupling electrode 40a and the first output coupling electrode 40b. You may make it. In this case, the connection points between the first input coupling electrode 40a and the first output coupling electrode 40b and the wiring conductor are the electric signal input point 45a of the first input coupling electrode 40a and the first output coupling electrode 40b. It becomes an electric signal output point 45b. When the input coupling auxiliary electrode 46a and the output coupling auxiliary electrode 46b are provided, the wiring conductor from the external circuit may be directly connected to the input coupling auxiliary electrode 46a and the output coupling auxiliary electrode 46b.

  Furthermore, 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. For example, a dielectric layer may be further disposed under the first ground electrode 21, or a dielectric layer may be further disposed over the second ground electrode 22.

  Furthermore, in the first to third examples of the embodiment described above, four first resonance electrodes 30a, 30b, 30c, 30d and four second resonance electrodes 31a, 31b, 31c, 31d are provided. Although an example has been shown, the number of first resonance electrodes and second resonance electrodes may be changed according to the required pass bandwidth and attenuation outside the pass band. If the required passband width is narrow or the attenuation outside the required passband is small, the number of resonant electrodes may be reduced. Conversely, the required passband width is wide. In some cases or when the required attenuation outside the passband is large, the number of resonant electrodes may be further increased. However, if the number of resonance electrodes increases too much, the size and the loss in the pass band increase, so the number of first resonance electrodes and second resonance electrodes is set to about 10 or less, respectively. Is desirable.

  Furthermore, in the first to third examples of the above-described embodiment, an example in which the number of first resonance electrodes is equal to the number of second resonance electrodes is shown. And the number of second resonance electrodes may be different.

  Furthermore, in the first example and the third example of the embodiment described above, in both the first resonance electrodes 30a, 30b, 30c, 30d and the second resonance electrodes 31a, 31b, 31c, 31d, In the second example of the above-described embodiment, each of the resonant electrodes is arranged side by side so that one end (ground end) of the resonant electrode is staggered and electromagnetically coupled to the interdigital type. Comline type electromagnetic field in which one end of the adjacent resonance electrode is located on the same side in both of the resonance electrodes 30a, 30b, 30c, 30d and the second resonance electrodes 31a, 31b, 31c, 31d. Although an example has been shown in which the interdigital electromagnetic field coupling arranged so that one end of the resonance electrode adjacent to the coupling is staggered is mixed, it is not necessary to have a symmetrical structure In the first case Electrodes 30a, 30b, 30c, 30d and the second resonance electrode 31a, 31b, 31c, at least one of all the resonance electrode of 31d may be configured to be electromagnetically coupled to the comb-line type. Further, the first resonance electrodes 30a, 30b, 30c, 30d and the second resonance electrodes 31a, 31b, 31c, 31d may be arranged in different coupling states.

  Furthermore, in the first to third examples of the above-described embodiment, an example in which the stacked body 10 is configured by one stacked body has been shown, but the stacked bodies are arranged so as to overlap each other in the stacking direction. The laminated body 10 may be configured by a plurality of laminated bodies. For example, in the bandpass filter of the first example of the above-described embodiment, the stacked body 10 is configured by the first stacked body and the second stacked body disposed thereon, and the first interlayer is The first interlayer is an interlayer, the second interlayer is an interlayer in the second stack disposed on the first stack, and the third interlayer is the first stack and the first stack. You may make it be an interlayer between two laminated bodies.

  Furthermore, the band-pass filter used for UWB has been described above as an example, but it goes without saying that the band-pass filter of the present invention is effective in other applications that require a wide band.

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

  The electrical characteristics of the bandpass filter of the third example of the embodiment shown in FIGS. 9 to 12 were calculated by simulation using a finite element method.

  As calculation conditions, the first resonance electrodes 30a, 30b, 30c, and 30d have a rectangular shape with a width of 0.175 mm, the length of the first resonance electrodes 30a and 30b is 3.4 mm, and the first resonance electrodes 30c and 30d. The length of was set to 3.5 mm. The distance between the first resonance electrode 30a and the first resonance electrode 30c and the distance between the first resonance electrode 30d and the first resonance electrode 30b are 0.08 mm, respectively. The distance from the electrode 30d was 0.095 mm. The plurality of second resonance electrodes 31a, 31b, 31c, and 31d have a rectangular shape with a width of 0.175 mm, the length of the second resonance electrodes 31a and 31b is 2.87 mm, and the length of the second resonance electrodes 31c and 31d. Was 2.93 mm. The distance between the second resonance electrode 31a and the second resonance electrode 31c and the distance between the second resonance electrode 31d and the second resonance electrode 31b are 0.075 mm, and the second resonance electrode 31c and the second resonance electrode The distance from 31d was 0.11 mm. The first resonance auxiliary electrodes 32a and 32b are arranged at a location 0.3 mm away from the other end of the first resonance electrodes 30a and 30b, and are 0.28 mm wide and 0.31 mm long, respectively. A rectangular shape having a width of 0.2 mm and a length of 0.5 mm toward one resonance electrode 30a, 30b was joined. The first resonance auxiliary electrodes 32c and 32d are respectively a rectangle having a width of 0.35 mm and a length of 0.39 mm arranged 0.2 mm away from the other end of the first resonance electrodes 30c and 30d, and the first A rectangular shape having a width of 0.2 mm and a length of 0.5 mm toward one resonance electrode 30c, 30d was joined. The first input coupling electrode 40a and the first output coupling electrode 40b have a rectangular shape with a width of 0.15 mm and a length of 2.1 mm. The second input coupling electrode 41a has a rectangular shape with a width of 0.175 mm and a length of 1.735 mm. The second input coupling electrode 41a has a portion of the first input coupling electrode 40a facing the first resonance electrode 30a via the input side connection conductor 43a. It was connected to the position of 0.77 mm from the center to the opposite side to the electric signal input point 45a. The second output coupling electrode 41b has a rectangular shape with a width of 0.175 mm and a length of 1.735 mm. The second output coupling electrode 41b has a first output coupling electrode 40b opposite to the first resonance electrode 30b via the output-side connection conductor 43b. It was connected to the position of 0.77 mm from the center to the opposite side to the electrical signal output point 45b. The input coupling auxiliary electrode 46a and the output coupling auxiliary electrode 46b were rectangular with a width of 0.15 mm and a length of 1.25 mm. The input terminal electrode 60a and the output terminal electrode 60b were each a square having a side of 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 3.8 mm and a length of 5 mm. The opening of the ground electrode 23 has a rectangular shape with a width of 3.1 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 3.1 mm and a length of 3.79 mm. The overall shape of the bandpass filter was a rectangular parallelepiped shape having a width of 3.8 mm, a length of 5 mm, and a thickness of 0.51 mm. The distance between the lower surface of the laminate 10 and the interlayer A is 0.115 mm, the distance between the interlayer A and the first interlayer, and the distance between the first interlayer and the third interlayer is 0.015 mm. The spacing between C and the interlayer D is 0.04 mm, the spacing between the interlayer C and the interlayer D is 0.065 mm, the spacing between the interlayer D and the second interlayer is 0.04 mm, and the spacing between the second interlayer and the top surface of the laminate 10. Was 0.14 mm. The thickness of each electrode was 0.01 mm, and the diameters of the input side connection conductor 43a, the output side connection conductor 43b, and the through conductor 50 were 0.1 mm. The relative dielectric constant of the dielectric layer 11 was 7.5.

  FIG. 14 is a graph showing the simulation results, where the horizontal axis represents frequency and the vertical axis represents attenuation, and shows the pass characteristic (S21) and reflection characteristic (S11) of the bandpass filter. According to the graph shown in FIG. 14, even though the thickness of the laminated body 10 is as thin as 0.51 mm, the impedance is well matched over the entire two very wide passbands, and it is flat and has low loss. Excellent passing characteristics are obtained. As a result, according to the band-pass filter of the present invention, it is found that an excellent pass characteristic that is flat and has low loss over the entire two wide pass bands can be obtained even with a very thin shape. The effectiveness of the invention was confirmed.

It is an external appearance perspective view which shows typically an example of embodiment of the band pass filter of this invention. It is a typical exploded perspective view of the example of the band pass filter shown in FIG. It is a top view which shows typically the upper and lower surfaces and interlayer of an example of the band pass filter shown in FIG. FIG. 2 is a cross-sectional view taken along the line P-P ′ of the example of the bandpass filter illustrated in FIG. 1. It is an external appearance perspective view which shows typically the other example of embodiment of the band pass filter of this invention. FIG. 6 is a schematic exploded perspective view of the example of the bandpass filter shown in FIG. 5. It is a top view which shows typically the upper and lower surfaces and interlayer of the example of a band pass filter shown in FIG. FIG. 6 is a cross-sectional view taken along the line Q-Q ′ of the example of the bandpass filter illustrated in FIG. 5. It is an external appearance perspective view which shows typically the further another example of embodiment of the band pass filter of this invention. FIG. 10 is a schematic exploded perspective view of the example of the bandpass filter shown in FIG. 9. FIG. 10 is a plan view schematically showing upper and lower surfaces and layers of the example of the bandpass filter shown in FIG. 9. FIG. 10 is a cross-sectional view taken along line R-R ′ of the example of the bandpass filter illustrated in FIG. 9. It is a block diagram which shows the structural example of the radio | wireless communication module and radio | wireless communication apparatus using the band pass filter of this invention. It is a figure which shows the simulation result of the electrical property of the band pass filter of this invention.

Explanation of symbols

10: Laminate
11: Dielectric layer
21: First ground electrode
22: Second ground electrode
30a, 30b, 30c, 30d: first resonance electrode
31a, 31b, 31c, 31d: second resonance electrodes
40a: first input coupling electrode
40b: first output coupling electrode
41a: second input coupling electrode
41b: second output coupling electrode
43a: Input side connection conductor
43b: Output side connection conductor
45a: Electric signal input point
45b: Electrical signal output point
80: Wireless communication module
81: Baseband
82: RF section
84: Antenna
85: Wireless communication equipment

Claims (6)

A laminate in which a plurality of dielectric layers are laminated;
A first ground electrode disposed on the lower surface of the laminate and a second ground electrode disposed on the upper surface;
A plurality of strip-shaped first resonances arranged side by side so as to be electromagnetically coupled to each other between the first layers of the multilayer body, each serving as a resonator that is grounded at one end and resonates at a first frequency. Electrodes,
A second frequency which is arranged side by side so as to be electromagnetically coupled to each other in a second layer different from the first layer of the laminate, and whose one end is grounded and is higher than the first frequency A plurality of strip-shaped second resonant electrodes that resonate at
The length of the first resonance electrode of the input stage among the plurality of first resonance electrodes disposed between the first layer and the second layer of the multilayer body. A first input coupling electrode in the form of a band having an electric signal input point to which an electric signal is input, while being electromagnetically coupled to face an area extending over half of the vertical direction;
Electromagnetic field coupling is opposed to a region extending over half the length direction of the first resonance electrode of the output stage among the plurality of first resonance electrodes arranged between the third layers of the laminate. And a strip-shaped first output coupling electrode having an electrical signal output point from which an electrical signal is output;
An electromagnetic wave facing the second resonance electrode of the input stage among the plurality of second resonance electrodes disposed between the first layer and the second layer of the laminate. A second input coupling electrode for field coupling;
An electromagnetic wave facing the second resonance electrode of the output stage among the plurality of second resonance electrodes disposed between the first layer and the second layer of the laminate. A second output coupling electrode for field coupling;
The plurality of first resonance electrodes and the plurality of second resonance electrodes are arranged to be orthogonal to each other when viewed from the stacking direction of the stacked body,
The second input coupling electrode is connected to the side farther from the electrical signal input point than the center in the length direction at the portion of the first input coupling electrode facing the first resonance electrode of the input stage. An electrical signal is input via the first input coupling electrode;
The second output coupling electrode is connected to the side farther from the electrical signal output point than the center in the length direction at the portion of the first output coupling electrode facing the first resonance electrode of the output stage. A band-pass filter characterized in that an electrical signal is output through a first output coupling electrode.   The second input coupling electrode is disposed so as to intersect the one end side with respect to the center in the length direction of the first resonance electrode of the input stage when viewed from the stacking direction of the stacked body. The output coupling electrode is arranged so as to intersect the one end side with respect to the center in the length direction of the first resonance electrode of the output stage when viewed from the stacking direction of the stacked body. The bandpass filter according to 1.   The second input coupling electrode is disposed between the third layers and integrated with the first input coupling electrode, and the second output coupling electrode is disposed between the third layers and the first layer. The band-pass filter according to claim 1, wherein the band-pass filter is integrated with the output coupling electrode.   The second input coupling electrode is disposed between layers closer to the second layer than the third layer, and is connected to the first input coupling electrode via an input-side connection conductor. The output coupling electrode is disposed between layers closer to the second layer than the third layer, and is connected to the first output coupling electrode via an output-side connection conductor. The band-pass filter according to claim 1 or 2.   A wireless communication module comprising the bandpass filter according to any one of claims 1 to 4.   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. Wireless communication equipment.

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