JP2009135627A - Band-pass filter, high-frequency module using the same, and radio communication apparatus using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a band-pass filter which has an ultra-wide band and also has a suitable pass-band width as a UWB band-pass filter, and to provide a high-frequency module using the same, and radio communication apparatus using the same. <P>SOLUTION: In the band-pass filter, an input-stage resonance electrode 30a, an intermediate-state resonance electrode 30c and an output-stage resonance electrode 30b functioning as a 1/2 resonator are disposed mutually in a comb-line form, and between different layers of a laminate, and also an input-side coupling electrode 40a facing the input-stage resonance electrode 30a in an interdigital form and an output-side coupling electrode 40b facing the output-stage resonance electrode 30b in an interdigital form are disposed between different layers of a laminate. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a bandpass filter, a high-frequency module using the same, and a wireless communication device using the same, and more particularly to a bandpass filter having a very wide passband that can be suitably used for UWB (Ultra Wide Band) and The present invention relates to a high-frequency module using the same 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. For example, according to the US FCC (Federal Communication Commission) regulation, a frequency band of 3.1 to 10.6 GHz is realized. It is planned to be used. 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 wide band 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 a microstrip-CPW broadside coupling structure” March 2005 Proceedings of the IEICE General Conference C-2-114 p. 147 JP 2004-180032 A

  However, each of the bandpass filters described above has problems, and is not suitable for a UWB bandpass filter.

  For example, the bandpass filter proposed in Non-Patent Document 1 has a problem that the passband width is too wide. That is, UWB finally uses the frequency band of 3.1 GHz to 10.6 GHz, but initially it is planned to use the frequency band of 3.1 GHz to 4.9 GHz, which is 45% in the specific band. . Therefore, a filter used for this is required to have a pass bandwidth of about 40% in a specific band. Moreover, it is necessary to consider the influence between W-LAN (802.11.a), and attenuation at 5.15 GHz is required. Therefore, the bandpass filter proposed in Non-Patent Document 1 having a characteristic that the passband width exceeds 100% in the specific band cannot be used because the passband 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 widened, it is 10 in a specific band. It was less than%. Therefore, it could not be used as a UWB band-pass filter that requires a wide pass bandwidth corresponding to 40% of the specific band.

  The present invention has been devised in view of such problems in the prior art, and an object thereof is a bandpass filter having an ultra-wideband and an appropriate passband as a UWB bandpass filter. Another object of the present invention is to provide a high-frequency module using the same and a wireless communication device using the same.

  In the present invention, a laminated body in which a plurality of dielectric layers are laminated, a first ground electrode arranged on the lower surface of the laminated body, connected to the ground potential, and arranged on the upper surface of the laminated body A half-wave resonator including a second ground electrode connected to the ground potential and at least an input stage resonant electrode and an output stage resonant electrode disposed in parallel between one layer of the laminate. A plurality of strip-shaped resonance electrodes, an annular earth electrode surrounding the plurality of resonance electrodes, disposed between the one layer of the multilayer body, and a layer above the one layer of the multilayer body A first input coupling electrode that is electromagnetically coupled to one end side region on one end side from the center in the length direction of the input stage resonance electrode, and the other from the center in the length direction of the input stage resonance electrode. Electromagnetic field coupling opposite the other end side area A second input coupling electrode, a first output coupling electrode that is electromagnetically coupled to one end side region on one end side from a center in a length direction of the output stage resonance electrode, and the output stage resonance electrode A second output coupling electrode that electromagnetically couples opposite the other end side region on the other end side from the center in the length direction, and the annular ground electrode between the layers above the one layer of the laminate. A plurality of auxiliary resonance electrodes connected to one end and the other end of each of the plurality of resonance electrodes by a through conductor, and the input stage resonance electrode of the first input coupling electrode The first signal input point is located in a region facing one quarter of the entire length of the input stage resonance electrode to a quarter of the total length of the input stage resonance electrode, and the other end of the input stage resonance electrode of the second input coupling electrodes. To 1/4 of the total length of the input stage resonant electrode A second signal input point in a region opposite to the region of the first output coupling electrode, from one end of the output stage resonant electrode to a quarter of the total length of the output stage resonant electrode. A first signal output point in a region facing the region, and a region from the other end of the output stage resonance electrode to a quarter of the total length of the output stage resonance electrode of the second output coupling electrode; It has the 2nd signal output point in the field which counters.

  According to the present invention, in the above configuration, an input point for inputting a signal is provided at one end between the layers above the one layer of the multilayer body, and the first signal input point and the through conductor are provided at the other end. A first auxiliary input coupling electrode having a connection point connected to each other and having a region opposite to the auxiliary resonance electrode connected to one end of the input stage resonance electrode on one end side, and a signal is input to one end. An auxiliary resonance electrode connected to the other end of the input stage resonance electrode on one end side, and having a connection point connected to the second signal input point via a through conductor at the other end. A second auxiliary input coupling electrode having opposing regions; an output point at which a signal is output at one end; and a connection point connected to the first signal output point through a through conductor at the other end Connected to one end of the output stage resonance electrode on one end side A first auxiliary output coupling electrode having a region opposite to the auxiliary resonance electrode, an output point at which a signal is output at one end, and the other end connected to the second signal output point via a through conductor. And a second auxiliary output coupling electrode having a region facing one of the auxiliary resonance electrodes connected to the other end of the output stage resonance electrode on one end side. is there.

  A high-frequency 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 that.

  According to the present invention, the first and second input coupling electrodes and the input stage resonance electrode are coupled in an interdigital manner, and similarly, the first and second output coupling electrodes and the output stage resonance electrode are constructed in an interdigital manner. Therefore, strong coupling is generated by adding the coupling by the magnetic field and the coupling by the electric field. As a result, even with a wide pass band far exceeding the range that can be realized with a filter using a conventional quarter wavelength resonator, a flat and low-loss pass characteristic is obtained over the entire pass band. Can have. In addition, according to the present invention, a plurality of auxiliary resonance electrodes connected to one end and the other end of each of the plurality of resonance electrodes by through conductors are provided so that the plurality of auxiliary resonance electrodes face the annular ground electrode. As a result, an electrostatic capacity is generated between the two opposing portions, so that the length of each resonance electrode can be shortened, and a small bandpass filter can be obtained.

  Furthermore, according to the band-pass filter of the present invention, one end has an input point where a signal is input and the other end has a connection point connected to the first signal input point via a through conductor. A first auxiliary input coupling electrode having a region facing the auxiliary resonant electrode connected to one end of the input stage resonant electrode, an input point for inputting a signal at one end, and a second signal input at the other end A second auxiliary input coupling electrode having an area connected to the auxiliary resonance electrode connected to the other end of the input stage resonance electrode on one end side, and a connection point connected to the point via a through conductor; Auxiliary resonance having an output point for outputting a signal and having a connection point connected to the first signal output point through a through conductor at the other end and connected to one end of the output stage resonance electrode at one end side First auxiliary output coupling having a region opposite the electrode A pole, an output point for outputting a signal at one end, a connection point connected to the second signal output point via a through conductor at the other end, and the other end of the output stage resonant electrode at one end side When the second auxiliary output coupling electrode having a region opposite to the connected auxiliary resonance electrode is provided, electromagnetic coupling occurs between the input stage auxiliary resonance electrode and the auxiliary input coupling electrode, and the input stage resonance occurs. Added to the electromagnetic coupling between the electrode and the input coupling electrode. Similarly, an electromagnetic coupling occurs between the output stage auxiliary resonance electrode and the auxiliary output coupling electrode, and between the output stage resonance electrode and the output coupling electrode. Is added to the electromagnetic coupling. As a result, the electromagnetic field coupling between the first and second input coupling electrodes and the input stage resonance electrode and the electromagnetic field coupling between the first and second output coupling electrodes and the output stage resonance electrode are further strengthened. It can have a flatter pass characteristic over the entire wide passband.

  Further, according to the high-frequency module of the present invention and the wireless communication device of the present invention, the band-pass filter of the present invention with a small loss of the signal passing over the entire communication band is used for filtering the transmission signal and / or the reception signal. As a result, the attenuation of the reception signal and the transmission signal passing through the band-pass filter is reduced, so that the reception sensitivity is improved, and the amplification degree of the transmission signal and / or the reception signal can be reduced. Become. Therefore, a high-performance high-frequency module and wireless communication device with high reception sensitivity and low power consumption can be obtained.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of a band-pass filter of the present invention, a high-frequency module using the same, and a wireless communication device using the same will be described in detail with reference to the accompanying drawings.

  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 bandpass filter shown in FIG. FIG. 3 is a plan view schematically showing the upper and lower surfaces of the bandpass filter shown in FIG. 1 and one surface between layers. 4 is a cross-sectional view taken along line AA of FIG.

  The bandpass filter according to the present embodiment includes a laminated body 10 in which a plurality of dielectric layers 11 are laminated, a first ground electrode 21 arranged on the lower surface of the laminated body 10, and an upper surface of the laminated body 10. Second earth electrode 22, strip-shaped input stage resonant electrode 30a and output stage resonant electrode 30b functioning as a half-wave resonator disposed between one layer of laminate 10, input stage resonant electrode 30a and output A band-shaped middle-stage resonance electrode 30c that functions as a half-wave resonator disposed between the stage-resonance electrode 30b and electromagnetically couples with the input-stage resonance electrode 30a and the output-stage resonance electrode 30b, and these resonance electrodes And an annular ground electrode 23 formed so as to surround (input stage resonance electrode 30a, output stage resonance electrode 30b, middle stage resonance electrode 30c).

  The first ground electrode 21 is on the entire lower surface of the multilayer body 10, and the second ground electrode 22 is the first input terminal electrode 60a, the second input terminal electrode 60c, and the first output terminal on the upper surface of the multilayer body 10. The electrodes 60b and the second output terminal electrode 60d are arranged on almost the entire surface except for the periphery, and all are connected to the ground potential and stripped together with the input stage resonance electrode 30a, the output stage resonance electrode 30b, and the middle stage resonance electrode 30c. A line resonator is configured. That is, the input stage resonant electrode 30a, the output stage resonant electrode 30b, and the middle stage resonant electrode 30c constitute a stripline resonator together with the first ground electrode 21 and the second ground electrode 22, and are a 1/2 wavelength resonator. Function as.

  The input stage resonance electrode 30a, the output stage resonance electrode 30b, and the middle stage resonance electrode 30c that function as a half-wave resonator are two resonance electrodes that each function as a quarter-wave resonator in the length direction. It corresponds to. That is, one end side region (for 1/4 wavelength) on one end side from the center in the length direction of the input stage resonance electrode 30a and one end side on one end side from the center in the length direction of the output stage resonance electrode 30b. The region (for ¼ wavelength) and the one end side region (for ¼ wavelength) on one end side from the center in the length direction of the middle-stage resonant electrode 30c disposed therebetween are electromagnetically coupled to each other. (Edge coupling). Further, the other end side region (for ¼ wavelength) on the other end side from the center in the length direction of the input stage resonance electrode 30a, and the other end side on the other end side from the center in the length direction of the output stage resonance electrode 30b. The region (for ¼ wavelength) and the other end side region (for ¼ wavelength) on the other end side from the center in the length direction of the middle-stage resonance electrode 30c disposed therebetween are electromagnetically coupled to each other. (Edge coupling).

  Here, a stronger coupling can be obtained when the distance between the middle-stage resonance electrode 30c and the input-stage resonance electrode 30a or the output-stage resonance electrode 30b is smaller. However, if the distance is reduced, manufacturing becomes difficult. It is set to about 0.5 mm.

  The annular ground electrode 23 is formed between the resonance electrodes (input stage resonance electrodes) in the same layer as the plurality of resonance electrodes (input stage resonance electrode 30a, output stage resonance electrode 30b, middle stage resonance electrode 30c) of the laminate 10. Electrode 30a, output stage resonance electrode 30b, and middle stage resonance electrode 30c). The annular ground electrode 23 itself is connected to the ground potential.

  The annular ground electrode 23 surrounds the input stage resonance electrode 30a, the output stage resonance electrode 30b, and the middle stage resonance electrode 30c in a ring shape, thereby surrounding the electromagnetic waves generated from the input stage resonance electrode 30a, the output stage resonance electrode 30b, and the middle stage resonance electrode 30c. Leakage can be reduced. This effect is particularly useful for preventing adverse effects on other regions of the module substrate when the band-pass filter is formed in a partial region of the module substrate.

  In addition, the band-pass filter of this embodiment has an input between layers above the layers where a plurality of resonance electrodes (input stage resonance electrode 30a, output stage resonance electrode 30b, middle stage resonance electrode 30c) and annular ground electrode 23 are arranged. The strip-shaped first input coupling electrode 40a and the second input coupling electrode 40c disposed so as to face the stage resonance electrode 30a, and the strip-shaped first output disposed so as to face the output stage resonance electrode 30b. A coupling electrode 40b and a second output coupling electrode 40d are provided.

  The first input coupling electrode 40a and the second input coupling electrode 40c are arranged so as to be electromagnetically coupled to each other so as to face the input stage resonance electrode 30a. Specifically, the first input coupling electrode 40a is disposed so as to oppose the one end side region of the input stage resonance electrode 30a so as to be electromagnetically coupled, and the second input coupling electrode 40c is connected to the input stage resonance electrode 30a. It arrange | positions so that an electromagnetic field coupling may be opposed facing the other end side area | region. Therefore, the first input coupling electrode 40a and the one end side region of the input stage resonance electrode 30a and the second input coupling electrode 40c and the other end side region of the input stage resonance electrode 30a are both broadside coupled, Compared to edge connection, the connection is stronger.

  Further, the first input coupling electrode 40a is a first electrode provided on the upper surface of the multilayer body 10 by through conductors 52a and 53a (shown by dotted lines in FIG. 2) and a first auxiliary input coupling electrode 41a described later. The second input coupling electrode 40c is connected to the input terminal electrode 60a, and the upper surface of the multilayer body 10 is formed by through conductors 52c and 53c (shown by dotted lines in FIG. 2) and a second auxiliary input coupling electrode 41c described later. Is connected to a second input terminal electrode 60c provided in the first input terminal. Here, the first signal input point 71a, which is a point where the first input coupling electrode 40a and the through conductor 52a are connected, is input from one end of the input stage resonance electrode 30a in the first input coupling electrode 40a. It is important to provide it in a region facing the region up to ¼ of the entire length of the stage resonance electrode 30a, and in this embodiment, it is a position facing one end vicinity of the input stage resonance electrode 30a. The second signal input point 71c, which is a point where the second input coupling electrode 40c and the through conductor 52c are connected, is connected to the input stage from the other end of the input stage resonance electrode 30a in the second input coupling electrode 40c. It is important to provide it in a region facing the region up to ¼ of the entire length of the resonance electrode 30a, and in this embodiment, it is in a position facing the vicinity of the other end of the input stage resonance electrode 30a. Note that the opposite ends (the other ends) of the first input coupling electrode 40a and the second input coupling electrode 40c are open ends. The balanced electric signal input from the external circuit is supplied from the first signal input point 71a to the first input coupling electrode 40a, and from the second signal input point 71c to the second input coupling electrode 40c. To be supplied.

  Thus, the first input coupling electrode 40a and the one end side region of the input stage resonance electrode 30a are coupled in an interdigital manner, and the second input coupling electrode 40c and the other end side region of the input stage resonance electrode 30a are It is coupled to the interdigital type, and the coupling by the magnetic field and the coupling by the electric field are added, and the coupling is stronger than the case of coupling to the combline type or the case of simply capacitive coupling. As described above, the first input coupling electrode 40a is broad-side coupled and interdigitally coupled to one end side region of the input stage resonant electrode 30a over the whole, and is one end side of the input stage resonant electrode 30a. Very tightly coupled with the area. Similarly, the second input coupling electrode 40c is very strongly coupled to the other end side region of the input stage resonance electrode 30a.

  On the other hand, the first output coupling electrode 40b and the second output coupling electrode 40d are also arranged with a plurality of resonance electrodes (input stage resonance electrode 30a, output stage resonance electrode 30b, middle stage resonance electrode 30c) and the annular ground electrode 23. Each layer is disposed between the layers above the layers so as to be electromagnetically coupled to each other so as to face the output stage resonance electrode 30b. Specifically, the first output coupling electrode 40b is disposed to oppose one end side region of the output stage resonance electrode 30b so as to be electromagnetically coupled, and the second output coupling electrode 40d is connected to the output stage resonance electrode 30b. It arrange | positions so that an electromagnetic field coupling may be opposed facing the other end side area | region. Therefore, the first output coupling electrode 40b and the one end side region of the output stage resonance electrode 30b and the second output coupling electrode 40d and the other end side region of the output stage resonance electrode 30b are both broadside coupled, Compared to edge connection, the connection is stronger.

  Further, the first output coupling electrode 40b is a first output provided on the upper surface of the multilayer body 10 by through conductors 52b and 53b (shown by dotted lines in FIG. 2) and a first auxiliary output coupling electrode 41b described later. The second output coupling electrode 40d is connected to the output terminal electrode 60b, and the second output coupling electrode 40d is formed on the upper surface of the multilayer body 10 by through conductors 52d and 53d (shown by dotted lines in FIG. 2) and a second auxiliary output coupling electrode 41d described later. Connected to a second output terminal electrode 60d. Here, the first signal output point 71b, which is a point where the first output coupling electrode 40b and the through conductor 52b are connected, is connected to the output stage from one end of the output stage resonance electrode 30b in the first output coupling electrode 40b. It is important to provide it in a region facing the region up to ¼ of the entire length of the resonance electrode 30b. In this embodiment, the resonance electrode 30b is positioned opposite to the vicinity of one end of the output stage resonance electrode 30b. Further, the second signal output point 71d, which is a point where the second output coupling electrode 40d and the through conductor 52d are connected, is connected to the output stage resonance from the other end of the output stage resonance electrode 30b in the second output coupling electrode 40d. It is important to provide the electrode 30b in a region facing the region up to ¼ of the entire length, and in this embodiment, the electrode 30b is positioned to face the vicinity of the other end of the output stage resonance electrode 30b. Note that the opposite ends (the other end) of the first output coupling electrode 40b and the second output coupling electrode 40d are open ends. The balanced electrical signal output to the external circuit is extracted from the first signal output point 71b and is extracted from the second signal output point 71d.

  As a result, the first output coupling electrode 40b and the one end side region of the output stage resonance electrode 30b are coupled in an interdigital manner, and the second output coupling electrode 40d and the other end side region of the output stage resonance electrode 30b are It is coupled to the interdigital type, and the coupling by the magnetic field and the coupling by the electric field are added, and the coupling is stronger than the case of coupling to the combline type or the case of simply capacitive coupling. As described above, the first output coupling electrode 40b is broad-side coupled and interdigitally coupled to one end side region of the output stage resonant electrode 30b over the whole, and is one end side of the output stage resonant electrode 30b. Very tightly coupled with the area. Similarly, the second output coupling electrode 40d is very strongly coupled to the other end side region of the output stage resonance electrode 30b.

  Thus, the first input coupling electrode 40a and the second input coupling electrode 40c and the input stage resonance electrode 30a are very strongly coupled, and the first output coupling electrode 40b and the second output coupling electrode 40d and the output are coupled. Since the stage resonant electrode 30b is very strongly coupled, even if it is a wide pass band far beyond the range that can be realized by a filter using a conventional quarter wavelength resonator, the pass band It can have a flat and low-loss passage characteristic over the entire area.

  The first input coupling electrode 40a and the second input coupling electrode 40c are preferably set to have the same shape and dimension as the input stage resonance electrode 30a, and the first output coupling electrode 40a and the second input coupling electrode 40c. The shape and size of 40b and the second output coupling electrode 40d are preferably set to the same level as the output stage resonance electrode 30b when these two are combined.

  Further, the distance between the first input coupling electrode 40a and the second input coupling electrode 40c and the input stage resonance electrode 30a, the first output coupling electrode 40b and the second output coupling electrode 40d, and the output stage resonance electrode 30b As for the interval, the coupling becomes stronger if it is made smaller, but it is difficult to manufacture, so it is set to about 0.01 to 0.5 mm, for example.

  Furthermore, the band-pass filter of this embodiment includes a plurality of resonance electrodes (input stage resonance electrode 30a, output stage resonance electrode 30b, and The first input coupling electrode 40a, the second input coupling electrode 40c, the first output coupling electrode 40b, and the second output between the resonance electrode 30c) and the interlayer provided with the annular ground electrode 23. The first input stage auxiliary resonance electrode 31a, the second input stage auxiliary resonance electrode 31c, the first output stage auxiliary resonance electrode 31b, and the second output stage auxiliary are provided in the same layer as the layer where the coupling electrode 40d is provided. A resonance electrode 31d, a first middle auxiliary resonance electrode 31e, and a second middle auxiliary resonance electrode 31f are provided.

  The first input stage auxiliary resonant electrode 31a is connected to one end of the input stage resonant electrode 30a by the through conductor 51a, and the second input stage auxiliary resonant electrode 31c is connected to the other end of the input stage resonant electrode 30a by the through conductor 51c. Each of the input stage auxiliary resonance electrodes 31 a and 31 c has a region facing the annular ground electrode 23.

  The first output stage auxiliary resonance electrode 31b is connected to one end of the output stage resonance electrode 30b by a through conductor 51b, and the second output stage auxiliary resonance electrode 31d is connected to the other end of the output stage resonance electrode 30b by a through conductor 51d. Each of the output stage auxiliary resonance electrodes 31 b and 31 d has a region facing the annular ground electrode 23.

  The first intermediate auxiliary resonance electrode 31e is connected to one end of the intermediate resonance electrode 30c by the through conductor 51e, and the second intermediate auxiliary resonance electrode 31f is connected to the other end of the intermediate resonance electrode 30c by the through conductor 51f. Each of the middle auxiliary resonance electrodes 31 e and 31 f has a region facing the annular ground electrode 23.

  According to this structure, a plurality of resonance electrodes can be combined in a comb line type, and a capacitance is generated between the resonance electrode and the annular ground electrode 23 in a region facing the annular earth electrode 23, thereby causing a plurality of resonances. Since the lengths of the electrodes (input stage resonance electrode 30a, output stage resonance electrode 30b, middle stage resonance electrode 30c) can be shortened, a small band-pass filter can be obtained.

The first input stage auxiliary resonance electrode 31a, the second input stage auxiliary resonance electrode 31c, the first output stage auxiliary resonance electrode 31b, the second output stage auxiliary resonance electrode 31d, the first middle stage auxiliary resonance electrode 31e, the first The area of the region where the middle auxiliary resonance electrode 31f of the 2 is opposed to the annular ground electrode 23 is set to, for example, about 0.01 to ³ mm ² in consideration of the necessary size and the obtained capacitance. Also, the first input stage auxiliary resonance electrode 31a, the second input stage auxiliary resonance electrode 31c, the first output stage auxiliary resonance electrode 31b, the second output stage auxiliary resonance electrode 31d, and the first middle stage auxiliary resonance electrode 31e. The smaller the distance between the second intermediate auxiliary resonance electrode 31f and the annular ground electrode 23, the larger the capacitance can be. However, it is difficult to manufacture, for example, about 0.01 to 0.5 mm. Set to

  Further, the band-pass filter of this embodiment includes an auxiliary input coupling electrode and an auxiliary output coupling electrode in addition to the above-described configuration.

  Specifically, a band-like layer is formed between layers above the layers where the first input coupling electrode 40a, the second input coupling electrode 40c, the first output coupling electrode 40b, and the second output coupling electrode 40d are provided. A first auxiliary input coupling electrode 41a, a strip-shaped second auxiliary input coupling electrode 41c, a strip-shaped first auxiliary output coupling electrode 41b, and a second auxiliary output coupling electrode 41d are provided.

  The first auxiliary input coupling electrode 41a is a region facing a region from one end of the input stage resonance electrode 30a in the first input coupling electrode 40a to ¼ of the total length of the input stage resonance electrode 30a by the through conductor 52a. And is disposed so as to face the first input stage auxiliary resonant electrode 31a, in other words, has a region facing the first input stage auxiliary resonant electrode 31a. A balanced electric signal is supplied to the first input coupling electrode 40a (first signal input point 71a) via the first auxiliary input coupling electrode 41a. The first auxiliary input coupling electrode 41a has an input point (a point connected to the first input terminal electrode 60a through the through conductor 53a) at one end and a first input at the other end. An auxiliary resonance electrode (first input stage auxiliary resonance electrode 31a) having a connection point connected to the signal input point 71a via the through conductor 52a and connected to one end of the input stage resonance electrode 30a on one end side It has opposing areas.

  As a result, the first auxiliary input coupling electrode 41a connected to the first input coupling electrode 40a and the first input stage auxiliary resonance electrode 31a connected to the input stage resonance electrode 30a are broadside coupled, Since the coupling is added to the coupling between the first input coupling electrode 40a and the input stage resonance electrode 30a, the coupling is stronger as a whole. Furthermore, the one end side region of the input stage resonance electrode 30a and the joined body of the first input stage auxiliary resonance electrode 31a connected thereto, the first input coupling electrode 40a and the first auxiliary input connected thereto. Since the joined body of the coupling electrode 41a is coupled in an interdigital manner as a whole, strong coupling is obtained by adding coupling by a magnetic field and coupling by an electric field. Therefore, in the length direction of the first auxiliary input coupling electrode 41a, stronger coupling is obtained compared to the case where the first auxiliary coupling electrode 41a is connected to the input terminal electrode 60a on the same side as the side connected to the first input coupling electrode 40a. Can be realized.

  Further, the second auxiliary input coupling electrode 41c is opposed to a region from the other end of the input stage resonance electrode 30a in the second input coupling electrode 40c to ¼ of the entire length of the input stage resonance electrode 30a by the through conductor 52c. And is arranged so as to face the second output stage auxiliary resonant electrode 31c, in other words, has a region facing the second input stage auxiliary resonant electrode 31c. A balanced electric signal is supplied to the second input coupling electrode 40c (second signal input point 71c) via the second auxiliary input coupling electrode 41c. The second auxiliary input coupling electrode 41c has an input point (a point connected to the second input terminal electrode 60c through the through conductor 53c) at one end and a second input at the other end. An auxiliary resonance electrode (second input stage auxiliary resonance electrode 31c) having a connection point connected to the signal input point 71c through the through conductor 52c and connected to the other end of the input stage resonance electrode 30a on one end side It has opposing areas.

  As a result, the second auxiliary input coupling electrode 41c connected to the second input coupling electrode 40c and the second input stage auxiliary resonance electrode 31c connected to the input stage resonance electrode 30a are broadside coupled, Since the coupling is added to the coupling between the second input coupling electrode 40c and the input stage resonance electrode 30a, the coupling is stronger as a whole. Further, the other end side region of the input stage resonance electrode 30c and the joined body of the second input stage auxiliary resonance electrode 31c connected thereto, the second input coupling electrode 40c and the second auxiliary input connected thereto. Since the joined body of the coupling electrode 41c is coupled in an interdigital manner as a whole, strong coupling is obtained by adding coupling by a magnetic field and coupling by an electric field. Therefore, in the length direction of the second auxiliary input coupling electrode 41c, stronger coupling is obtained compared to the case where it is connected to the input terminal electrode 60a on the same side as the side connected to the second input coupling electrode 40c. Can be realized.

  On the other hand, the first auxiliary output coupling electrode 41b is opposed to the region from one end of the output stage resonance electrode 30b in the first output coupling electrode 40b to ¼ of the total length of the output stage resonance electrode 30b by the through conductor 52b. The first output stage auxiliary resonance electrode 31b is disposed so as to face the first output stage auxiliary resonance electrode 31b. In other words, the first output stage auxiliary resonance electrode 31b is opposed to the first output stage auxiliary resonance electrode 31b. A balanced electrical signal is taken out from the first output coupling electrode 40b (first signal output point 71b) via the first auxiliary output coupling electrode 41b. The first auxiliary output coupling electrode 41b has an output point (a point connected to the first output terminal electrode 60b via the through conductor 53b) at one end and a first output at the other end. An auxiliary resonance electrode (first output stage auxiliary resonance electrode 31b) having a connection point connected to the signal output point 71b through the through conductor 52b and connected to one end of the output stage resonance electrode 30b on one end side. It has opposing areas.

  As a result, the first auxiliary output coupling electrode 41b connected to the first output coupling electrode 40b and the first output stage auxiliary resonance electrode 31b connected to the output stage resonance electrode 30b are broadside coupled, Since the coupling is added to the coupling between the first output coupling electrode 40b and the output stage resonance electrode 30b, the coupling is stronger as a whole. The first auxiliary output coupling electrode 41b is connected to the output terminal electrode 60b through the through conductor 53b just in the region facing the first output stage auxiliary resonance electrode 31b. As a result, the one end region of the output stage resonance electrode 30b and the joined body of the first output stage auxiliary resonance electrode 31b connected thereto, the first output coupling electrode 40b, and the first auxiliary connected to the same. Since the joined body of the output coupling electrode 41b is coupled in an interdigital manner as a whole, strong coupling is obtained by adding coupling by a magnetic field and coupling by an electric field. Therefore, in the longitudinal direction of the first auxiliary output coupling electrode 41b, stronger coupling is obtained as compared with the case where it is connected to the output terminal electrode 60b on the same side as the side connected to the first output coupling electrode 40b. Can be realized.

  Further, the second auxiliary output coupling electrode 41d is opposed to the region from the other end of the output stage resonance electrode 30b in the second output coupling electrode 40d to ¼ of the total length of the output stage resonance electrode 30b by the through conductor 52d. And is disposed so as to face the second output stage auxiliary resonant electrode 31d, in other words, has a region facing the second output stage auxiliary resonant electrode 31d. A balanced electric signal is extracted from the second output coupling electrode 40d (second signal output point 71d) via the second auxiliary output coupling electrode 41d. Note that an output point (a point connected to the second output terminal electrode 60d via the through conductor 53d) is provided at one end and the second signal output point and the through conductor 52d are provided at the other end. And has a region facing one side of the auxiliary resonance electrode (second output stage auxiliary resonance electrode) connected to the other end of the output stage resonance electrode 30b.

  As a result, the second auxiliary output coupling electrode 41d connected to the second output coupling electrode 40d and the second output stage auxiliary resonance electrode 31d connected to the output stage resonance electrode 30b are broadside coupled, Since the coupling is added to the coupling between the second output coupling electrode 40d and the output stage resonance electrode 30b, the coupling is stronger as a whole. The second auxiliary output coupling electrode 41d is connected to the input terminal electrode 60d via the through conductor 53d just in the region facing the second output stage auxiliary resonance electrode 31d. Thereby, the other end side region of the output stage resonance electrode 30b and the joined body of the second output stage auxiliary resonance electrode 31d connected thereto, the second output coupling electrode 40d and the second auxiliary electrode connected thereto. Since the joined body of the output coupling electrode 41d is coupled in an interdigital manner as a whole, strong coupling is obtained by adding coupling by a magnetic field and coupling by an electric field. Therefore, in the length direction of the second auxiliary output coupling electrode 41d, stronger coupling is obtained as compared with the case where it is connected to the output terminal electrode 60d on the same side as the side connected to the second output coupling electrode 40d. Can be realized.

  According to such a structure, even in a very wide pass band, the insertion loss at a frequency located between the resonance frequencies of the respective resonance modes is further reduced, and a band pass filter having a flatter pass characteristic is obtained. Obtainable.

  The widths of the first auxiliary input coupling electrode 41a, the second auxiliary input coupling electrode 41c, the first auxiliary output coupling electrode 41b, and the second auxiliary output coupling electrode 41d are, for example, the first input coupling electrode 40a. The second input coupling electrode 40c, the first output coupling electrode 40b, and the second output coupling electrode 40d are set to the same degree. The lengths of the first auxiliary input coupling electrode 41a, the second auxiliary input coupling electrode 41c, the first auxiliary output coupling electrode 41b, and the second auxiliary output coupling electrode 41d are, for example, the first input stage auxiliary The lengths of the resonance electrode 31a, the first output stage auxiliary resonance electrode 31b, the second input stage auxiliary resonance electrode 31c, and the second output stage auxiliary resonance electrode 31d are set slightly longer. The first auxiliary input coupling electrode 41a, the second auxiliary input coupling electrode 41c, the first auxiliary output coupling electrode 41b, the second auxiliary output coupling electrode 41d, the first input stage auxiliary resonance electrode 31a, the second input The smaller distance between the stage auxiliary resonance electrode 31c, the first output stage auxiliary resonance electrode 31b, and the second output stage auxiliary resonance electrode 31d is desirable in terms of causing strong coupling, but it becomes difficult in manufacturing. For example, it is set to about 0.01 to 0.5 mm.

  In this way, according to the bandpass filter of this embodiment, it is flat over the entire region of a very wide passband that far exceeds the region that could be realized by a filter using a conventional quarter wavelength resonator. It is possible to obtain a high-performance bandpass filter that can be suitably used as a UWB filter and has a low-loss pass characteristic.

  In this embodiment, the first and second auxiliary input coupling electrodes 41a and 41c and the first and second auxiliary output coupling electrodes 41b and 41d are provided, but these are not provided. Also good. In addition, a configuration is shown in which, as a plurality of resonance electrodes, one middle stage resonance electrode is provided in addition to the input stage resonance electrode and the output stage resonance electrode. A configuration in which no resonant electrode is provided may be used, or a configuration in which two or more resonant electrodes are provided may be used.

  Further, although the input coupling electrode, the output coupling electrode, and the auxiliary resonance electrode are arranged in the same layer, they may be arranged in different layers.

  Further, although not shown, the first input stage auxiliary resonance electrode 31a, the first input stage auxiliary resonance electrode 31a, and the first resonance resonance electrode 31a are provided between the layers provided with the plurality of resonance electrodes (input stage resonance electrode 30a, output stage resonance electrode 30b, middle stage resonance electrode 30c). A first output stage auxiliary resonance electrode 31b, a second input stage auxiliary resonance electrode 31c, a second output stage auxiliary resonance electrode 31d, a first middle stage auxiliary resonance electrode 31e, and a second middle stage auxiliary resonance electrode 31f; Thus, the input stage auxiliary resonance electrode, the output stage auxiliary resonance electrode, and the middle stage auxiliary resonance are also provided in layers below the layers where the resonance electrodes (input stage resonance electrode 30a, output stage resonance electrode 30b, middle stage resonance electrode 30c) are provided. An electrode may be provided. Thus, when the capacitance is increased, the resonance electrodes (input stage resonance electrode 30a, output stage resonance electrode 30b, middle stage resonance electrode 30c) can be further shortened, and when the capacitance is not increased. The area of the auxiliary resonant electrode can be reduced, and in any case, a smaller bandpass filter can be obtained.

  Furthermore, the first auxiliary input coupling electrode 41a and the second auxiliary input coupling electrode 41c are provided in a different layer from the layer in which the first auxiliary input coupling electrode 41a and the second auxiliary input coupling electrode 41c are provided. The first input stage auxiliary resonance electrode provided in a different layer from the layer provided with the electrode connected via the through conductor and the first input stage auxiliary resonance electrode 31a and the second input stage auxiliary resonance electrode 31c. The first input coupling electrode 40a (second input coupling electrode) is formed by disposing the electrode 31a and the electrode connected to the second input stage auxiliary resonant electrode 31c via a through conductor so as to face each other between different layers. 40c) and the first auxiliary input coupling electrode 41a (second auxiliary input coupling electrode 41c) and the input stage resonance electrode 30a and the first input stage auxiliary resonance electrode 31a (second input stage auxiliary resonance electrode 31c). Join Addition to, it may be made to have a stronger binding. Similarly, the first auxiliary output coupling electrode 41b and the second auxiliary output coupling electrode 41d are provided in a different layer from the layer in which the first auxiliary output coupling electrode 41b and the second auxiliary output coupling electrode 41d are provided. The first output stage auxiliary resonance electrode provided in an interlayer different from the layer provided with the electrode connected through the through conductor and the first output stage auxiliary resonance electrode 31b and the second output stage auxiliary resonance electrode 31d. The first output coupling electrode 40b (second output coupling electrode) is formed by arranging the electrode 31b and the electrode connected to the second output stage auxiliary resonance electrode 31d through a through conductor so as to face each other between different layers. 40d) and the first auxiliary output coupling electrode 41b (second auxiliary output coupling electrode 41d) and the output stage resonance electrode 30b and the first output stage auxiliary resonance electrode 31b (second output stage auxiliary resonance electrode 31d). Join Then, it may be to have a stronger binding. This further reduces the increase in insertion loss at frequencies located between the resonant frequencies of the respective resonant modes, even at very wide passband widths, and is flatter over the entire very wide passband. A band-pass filter having a lower loss pass characteristic can be obtained.

  In the example of the embodiment described above, an example in which the first and second input terminal electrodes 60a and 60c and the first and second output terminal electrodes 60b and 60d are provided has been described. When a bandpass filter is formed in the region, the first and second input terminal electrodes 60a and 60c and the first and second output terminal electrodes 60b and 60d are not necessarily required.

  FIG. 5 is a block diagram showing a configuration example of a high-frequency module 80 using the band-pass filter of the present invention and a wireless communication device 85 using the same.

  The high-frequency 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 of the baseband signals and before demodulation. It has.

  The RF unit 82 includes the above-described band-pass filter 821 of the present invention. The RF signal obtained by modulating the baseband signal or the received RF signal is band-limited (a signal having a frequency other than the communication band is attenuated). And pass through a bandpass filter 821. The input side (baseband unit 81 side) and the output side (antenna end side) of the bandpass filter 821 have a balanced circuit configuration.

  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 a balanced antenna 84 to the output side of the bandpass filter 821 (the output side of the high frequency module 80), the wireless communication device 85 of the present invention that transmits and receives RF signals is configured.

  According to such a configuration, by using the bandpass filter 821 of the present invention in which the loss of the signal passing through the entire communication band is small, the attenuation of the transmission signal and the reception signal passing through the bandpass filter 821 is small. Therefore, the reception sensitivity is improved. Furthermore, since the amplification degree of the transmission signal and the reception signal can be reduced, power consumption in the amplifier circuit is reduced. Therefore, a high-performance high-frequency module 80 and a wireless communication device 85 with high reception sensitivity and low power consumption can be obtained.

  The configuration of the high-frequency module 80 is not limited to the above configuration. Examples of the wireless communication device 85 include a mobile phone, a wireless card, and a router, but are not particularly limited.

In the bandpass 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. Moreover, as thickness of the dielectric material layer 11, it sets to about 0.01-0.1 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, 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 form a slurry, and a ceramic green sheet is formed by a doctor blade method. Next, a through hole to be a through conductor is formed in the obtained ceramic green sheet using a punching machine or the like, and a through conductor is formed by filling a conductor paste such as Ag, Ag-Pd, Au, Cu or the like. Next, the various electrodes described above are formed on the ceramic green sheet using a printing method. Next, these are laminated, pressed using a hot press apparatus, and fired at 800 to 1050 ° C.

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 band pass filter shown in FIG. It is a top view which shows typically the upper and lower surfaces of the bandpass filter shown in FIG. 1, and one surface between each layer. It is the sectional view on the AA line of FIG. It is a block diagram which shows the structural example of the high frequency module using the band pass filter of this invention, and a radio | wireless communication apparatus using the same.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10: Laminated body 11: Dielectric layer 21: 1st earth electrode 22: 2nd earth electrode 23: Annular earth electrode 30a: Input stage resonance electrode 30b: Output stage resonance electrode 30c: Middle stage resonance electrode 31a: 1st Input stage auxiliary resonant electrode 31b: first output stage auxiliary resonant electrode 31e: first middle stage auxiliary resonant electrode 31c: second input stage auxiliary resonant electrode 31d: second output stage auxiliary resonant electrode 31f: second middle stage Auxiliary resonant electrode 40a: first input coupling electrode 40b: first output coupling electrode 40c: second input coupling electrode 40d: second output coupling electrode 41a: first auxiliary input coupling electrode 41c: second auxiliary Input coupling electrode 41b: first auxiliary output coupling electrode 41d: second auxiliary output coupling electrode 51a, 51b, 51c, 51d, 51e, 51f: through conductors 52a, 52b, 52c, 52 : Through conductors 53a, 53b, 53c, 53d: Through conductors 71a: First signal input point 71c: Second signal input point 71b: First signal output point 71d: Second signal output point 80: High frequency module 85 : Wireless communication equipment

Claims (4)

A laminate in which a plurality of dielectric layers are laminated;
A first ground electrode disposed on the lower surface of the laminate and connected to a ground potential;
A second ground electrode disposed on the top surface of the laminate and connected to a ground potential;
A plurality of strip-shaped resonance electrodes functioning as a half-wave resonator including at least an input stage resonance electrode and an output stage resonance electrode, arranged in parallel between one layer of the laminate;
An annular ground electrode disposed between the one layer of the laminate and surrounding the plurality of resonant electrodes;
A first input that is electromagnetically coupled facing one end side region on one end side from the center in the length direction of the input stage resonance electrode, disposed between layers above the one layer of the laminate. A coupling electrode, a second input coupling electrode that is electromagnetically coupled to the other end side region on the other end side from the center in the length direction of the input stage resonance electrode, and a length direction of the output stage resonance electrode A first output coupling electrode that is electromagnetically coupled opposite one end region on one end side from the center, and the other end side region on the other end side from the center in the length direction of the output stage resonance electrode. A second output coupling electrode for electromagnetic coupling;
A plurality of auxiliary resonances disposed between the layers above the one layer of the multilayer body so as to face the annular ground electrode and connected to one end and the other end of each of the plurality of resonance electrodes by through conductors With electrodes,
The first input coupling electrode has a first signal input point in a region facing a region from one end of the input stage resonance electrode to a quarter of the total length of the input stage resonance electrode, and the first input coupling electrode. A second signal input point in a region facing the region from the other end of the input stage resonant electrode to ¼ of the total length of the input stage resonant electrode among the two input coupling electrodes;
The first output coupling electrode has a first signal output point in a region facing a region from one end of the output stage resonant electrode to ¼ of the total length of the output stage resonant electrode, A band having a second signal output point in a region facing the region from the other end of the output stage resonance electrode to ¼ of the total length of the output stage resonance electrode among the two output coupling electrodes. Path filter. Between the layers above the one layer of the laminate,
One end has an input point for inputting a signal, and the other end has a connection point connected to the first signal input point via a through conductor, and is connected to one end of the input stage resonance electrode on one end side. A first auxiliary input coupling electrode having a region facing the auxiliary resonant electrode formed;
One end has an input point for inputting a signal, and the other end has a connection point connected to the second signal input point via a through conductor, and is connected to the other end of the input stage resonance electrode on one end side. A second auxiliary input coupling electrode having a region facing the auxiliary auxiliary electrode formed;
One end has an output point for outputting a signal, and the other end has a connection point connected to the first signal output point via a through conductor, and is connected to one end of the output stage resonance electrode on one end side. A first auxiliary output coupling electrode having a region facing the auxiliary auxiliary electrode formed;
One end has an output point for outputting a signal, and the other end has a connection point connected to the second signal output point via a through conductor, and is connected to the other end of the output stage resonance electrode on one end side. The band pass filter according to claim 1, further comprising a second auxiliary output coupling electrode having a region facing the auxiliary resonance electrode formed. A high-frequency module comprising the band-pass filter according to claim 1. A radio 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. Communication equipment.

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