WO2005091427A1 - Filter - Google Patents

Abstract

A filter in which the overall size is reduced in plan view while utilizing a folded waveguide. The filter comprises a waveguide (B1) formed in a multilayer substrate (PC) while being surrounded by conductor layers (15, 17) arranged oppositely across a dielectric layer (A1) and a conductor wall constituted of conductors (TH) for conducting the conductor layers (15, 17), and a waveguide (B2) formed in the multilayer substrate (PC) along the waveguide (B1) while being surrounded by conductor layers (17, 21) and a conductor wall constituted of conductors (TH) for conducting the conductor layers (17, 21). Each waveguide (B1, B2) is closed at one end part on the same direction side along the longitudinal direction and coupled, at each end part, through a coupling window (31) arranged in the conductor layer (17).

Description

 Huinoleta

 Technical field

 The present invention relates to a filter having a folded waveguide structure for electromagnetic waves (high-frequency signals) such as microwaves and millimeter waves.

 Background art

 [0002] As a structure of a folded waveguide, a folded waveguide disclosed in Japanese Patent Application Laid-Open No. Hei 9 199901 is known. According to this folded waveguide, a small-sized antenna with stable performance can be constructed by folding the rectangular waveguide.

 Disclosure of the invention

 [0003] In recent years, with the advancement of mobile communication technology and the like, the frequency band of radio waves used for communication has expanded to a high-frequency range such as the GHz band, and communication equipment used for communication has become smaller. I'm advancing. For this reason, there is a demand for a high-frequency filter used in this type of communication device to be further compatible with small-sized filters. Of these, it is conceivable to meet the demand for miniaturization by reducing the area occupied by the filter by adopting the configuration of the folded waveguide disclosed in the above publication. However, in the folded waveguide disclosed in the above-mentioned publication, there is a problem that it is difficult to achieve the miniaturization that can sufficiently satisfy the requirements because the rectangular waveguide is used.

[0004] On the other hand, recently, a configuration is made using a pair of ground electrodes provided with a dielectric layer interposed therebetween, and a through-hole (conductive body) provided between the respective ground electrodes and conducting them. Then, a waveguide type waveguide capable of propagating an electromagnetic wave has been developed, and by using this waveguide type waveguide, a significantly small filter can be realized. By the way, the inventor of the present application considered applying the configuration of the folded waveguide disclosed in the above-mentioned publication to a filter using this waveguide type waveguide, which further reduces the size of the filter. In this case, it is preferable to adopt a configuration in which one waveguide-type waveguide and the other waveguide-type waveguide constituting the folded waveguide-type waveguide are formed between a pair of common ground electrodes. investigated. However, in this configuration, each waveguide-type waveguide has Since the filters are arranged side by side, there is a problem that the outer shape of the filter in a plan view when the filter using the folded waveguide type waveguide is formed in the multilayer substrate is increased.

 [0005] The present invention has been made to solve a large problem, and has as its main object to provide a filter that can reduce the outer shape in a plan view while using a folded waveguide type waveguide. Do

[0006] The filter according to the present invention provides a conductor constituted by first and second ground electrodes disposed to face each other with a dielectric layer interposed therebetween, and a conductor that conducts between these ground electrodes. A first waveguide-type waveguide formed in a multilayer substrate surrounded by a wall, one of the first and second ground electrodes, and one of the ground electrodes with a dielectric layer interposed therebetween; A third ground electrode disposed opposite to the first ground electrode, and a first ground electrode and a conductive wall formed by a conductive body for conducting the third ground electrode. A second waveguide formed along the waveguide, and each waveguide is closed at an end in the same direction along the length direction. And one ground electrode at each of these ends. Linked to each other through a provided binding window, Ru.

 [0007] In this case, each of the waveguide type waveguides is connected to each other via the other coupling window provided on one ground electrode at the other portion except for the end in the same direction. Can be linked.

[0008] Further, the filter according to the present invention is constituted by first and second ground electrodes disposed to face each other with a dielectric layer interposed therebetween, and a conductor that conducts between these ground electrodes. A first waveguide formed in the multilayer substrate surrounded by the formed conductor wall, one of the first and second ground electrodes, and one of the first and second ground electrodes with the dielectric layer interposed therebetween. A third ground electrode disposed opposite to the first ground electrode, and one of the ground electrodes and a conductive body formed of a conductor that conducts between the third ground electrode. A second waveguide formed along the first waveguide, a second ground electrode of the first and second ground electrodes, a third ground electrode, and This other ground electrode and this third Surrounded by the configured conductive wall by conduction member which through electrically between land electrodes when formed into multilayer substrate co And a resonator disposed at an end in the same direction along the length direction of each waveguide type waveguide, and each end of the waveguide type waveguide has a resonance. Are connected to each other via a container.

 [0009] In this case, each waveguide type waveguide can be connected to each other via a coupling window provided on one ground electrode.

 [0010] Furthermore, the other of the first and second ground electrodes is disposed on the same layer as the other ground electrode, and is connected to the first waveguide. The input line for input to the tubular waveguide and the third ground electrode are disposed opposite to the input line on the same layer as the second ground waveguide with one ground electrode interposed therebetween. And an output line for outputting an electromagnetic wave having the force of the second waveguide. The input line and the output line are coupled to each other through a coupling window formed in one ground electrode. Can be made.

 [0011] Further, the filter according to the present invention includes a pair of waveguide-type waveguides arranged in a multilayer substrate configured by alternately stacking a plurality of ground electrodes and dielectric layers. The tubular waveguide is surrounded by a pair of ground electrodes disposed to face each other with a dielectric layer interposed therebetween, and a conductor wall formed by a conductor that conducts between the pair of ground electrodes. Are formed by stacking a plurality of the resonators formed along the stacking direction of the multilayer substrate, are arranged in parallel with each other while sharing a conductor wall located therebetween, and are arranged along the stacking direction. At the ends in the same direction, the resonators are connected to each other via a coupling window formed in a conductor wall located between the resonators! Puru.

 [0012] In this case, the resonators other than the resonators at each end that constitute each waveguide type waveguide are connected to each other via a coupling window formed in a conductor wall located therebetween. can do.

[0013] In the filter according to the present invention, a pair of waveguides is provided in a multilayer substrate formed by alternately stacking a plurality of ground electrodes and dielectric layers. Resonators were provided at respective ends of each waveguide type waveguide in the same direction along the stacking direction of the multilayer substrate, and the resonators were provided to face each other with a dielectric layer interposed therebetween. A conductor constituted by a pair of ground electrodes and a conductor that conducts between the pair of ground electrodes. Each waveguide type waveguide is formed by being surrounded by a wall, and each of the waveguide type waveguides includes a pair of ground electrodes disposed to face each other with a dielectric layer interposed therebetween, and a conductor that conducts between the pair of ground electrodes. Thus, a plurality of resonators formed by being surrounded by the configured conductor walls are stacked along the stacking direction of the multi-layer substrate, and the resonators formed in parallel with each other share the conductor walls located therebetween. And connected to each other by connecting the resonators via the resonators disposed at the respective ends.

 [0014] In this case, the resonators forming each waveguide type waveguide can be connected to each other via a coupling window formed in a conductor wall located between the resonators.

 [0015] According to the filter of the present invention, the filter includes the first waveguide and the second waveguide, and closes the ends in the same direction along the length direction. The first and second waveguides are formed by configuring each waveguide type waveguide at the end of the bracket so as to be connected to each other through a coupling window provided on one of the ground electrodes. A folded waveguide waveguide in which the tubular waveguides overlap each other in a plan view state can be formed in the multilayer substrate. Therefore, the outer shape of the filter when the ground electrode is viewed in plan can be sufficiently reduced.

 [0016] Further, according to the filter of the present invention, at each of the other parts except the end in the same direction, each of the waveguide type waveguides is provided through another coupling window provided on one of the ground electrodes. Are connected to each other, a plurality of propagation paths (multipath paths) for electromagnetic waves are formed, and as a result, an attenuation pole can be formed. Therefore, a filter having a desired frequency characteristic can be realized by appropriately setting the formation position and size of the coupling window.

 According to the filter of the present invention, the filter includes the first waveguide, the second waveguide, and the resonator, and the end in the same direction is provided via the resonator. By configuring each waveguide type waveguide to be connected to each other, the second waveguide type waveguide is placed on the first waveguide type waveguide in a state where the ground electrode is viewed in plan. The two waveguide type waveguides can be formed in the multilayer substrate in a folded state. Therefore, the external shape of the ground electrode in a plan view can be sufficiently reduced.

[0018] Further, according to the filter of the present invention, by connecting each waveguide-type waveguide to each other via the coupling window provided on one of the ground electrodes, a plurality of propagation paths for electromagnetic waves can be obtained. As a result of forming a path (multipath path), an attenuation pole can be formed. Therefore, a filter having a desired frequency characteristic can be realized by appropriately setting the position and size of the coupling window.

 Further, according to the filter of the present invention, the input line and the output line are coupled to each other via the coupling window formed in one of the ground electrodes, so that a plurality of propagation paths for electromagnetic waves are provided. (Multipath path) can be formed between the input line and the output line to form a new attenuation pole. Therefore, filters having various frequency characteristics can be realized.

 According to the filter of the present invention, a pair of waveguides is provided in the multilayer substrate, and each of the waveguides is surrounded by a pair of ground electrodes and a conductor wall. A plurality of resonators formed by stacking are stacked along the stacking direction of the multilayer substrate, and are arranged in parallel with each other while sharing a conductor wall located therebetween, and in the same direction along the stacking direction. The resonators are connected to each other via a coupling window formed in a conductor wall positioned between the resonators at the end on the side, so that the first resonators extend in a direction orthogonal to the ground electrode. And the second waveguide can be formed in the multilayer substrate. Therefore, the first and second waveguides cannot be overlapped with each other when the ground electrode is viewed in a plan view! Can be sufficiently miniaturized. Therefore, the outer shape of the filter when the ground electrode is viewed in plan can be sufficiently reduced.

 [0021] Further, according to the filter of the present invention, among the resonators constituting each waveguide type waveguide, the resonators other than the resonators at each end are connected to the conductor wall located therebetween. By mutually connecting via the formed coupling window, a plurality of propagation paths (multipath paths) for the electromagnetic wave are formed, so that an attenuation pole can be formed. Therefore, a filter having a desired frequency characteristic can be realized by appropriately setting the position and size of the coupling window.

According to the filter of the present invention, a pair of waveguides and a resonator are provided in a multilayer substrate, and the resonator is surrounded by a pair of ground electrodes and a conductor wall. Each waveguide type waveguide is formed by being surrounded by a pair of ground electrodes and a conductor wall. Resonators are stacked along the stacking direction of the multilayer substrate, the conductor walls located between them are shared, and the resonators are arranged in parallel with each other, and the resonators are arranged at each end. By connecting to each other via a resonator, the first and second waveguides are formed in the multilayer substrate along a direction orthogonal to the ground electrode by connecting to each other. can do. For this reason, the first and second waveguides cannot be overlapped with each other when the ground electrode is viewed in a plan view, but the outer shape of each of the waveguides themselves in a plan view is sufficiently reduced. Can be miniaturized. Furthermore, when the ground electrode is viewed in a plan view, each waveguide type waveguide is included within the area occupied by the resonators disposed at the respective ends in the same direction along the stacking direction of the multilayer substrate. Therefore, even if the configuration is provided with the resonator, it is possible to avoid a large external shape. Therefore, the outer shape of the filter when the ground electrode is viewed in plan can be sufficiently reduced.

 According to the filter of the present invention, the resonators forming each waveguide type waveguide are connected to each other via a coupling window formed in a conductor wall located between the resonators. As a result, a plurality of propagation paths (multi-noss paths) for the electromagnetic wave are formed, so that an attenuation pole can be formed. Therefore, a filter having a desired frequency characteristic can be realized by appropriately setting the formation position and size of the coupling window.

 Brief Description of Drawings

FIG. 1 is a perspective view showing a configuration of a filter according to an embodiment of the present invention.

 FIG. 2 is an exploded perspective view of the filter shown in FIG. 1.

 FIG. 3 is a simplified perspective view of the configuration of the filter shown in FIG. 1.

 FIG. 4 is a cross-sectional view of the filter shown in FIG. 3, taken along line XX.

 FIG. 5 is a frequency characteristic diagram of a filter showing a relationship between frequency and attenuation.

 FIG. 6 is a cross-sectional view for describing the configuration and operation of a filter according to a modification.

 FIG. 7 is a frequency characteristic diagram of a filter showing a relationship between frequency and attenuation.

 FIG. 8 is a cross-sectional view for describing the configuration and operation of a filter according to another modification.

FIG. 9 is a perspective view showing a configuration of a filter according to another modification. FIG. 10 is a sectional view taken along line XI-XI of the filter shown in FIG. 9.

 FIG. 11 is a perspective view showing a configuration of a filter according to another modification.

 FIG. 12 is a sectional view taken along line X2-X2 of the filter shown in FIG.

 FIG. 13 is a perspective view showing a configuration of a filter according to another modification.

 FIG. 14 is a cross-sectional view of a filter according to another modification.

 BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, a preferred embodiment of a filter according to the present invention will be described with reference to the accompanying drawings.

 First, a configuration of a filter according to the present invention will be described with reference to the drawings.

As shown in FIG. 1, the filter 1 includes an input line 2, a plurality (four as an example) of resonators 3, 4, 5, and 6, and an output line 7. (Substrate) Formed in PC. Note that, in FIG. 1, a conductor or a conductor layer, which will be described later, is partially cut away or omitted to facilitate understanding of the description.

[0028] As shown in Figs. 1 and 2, the multilayer substrate PC is formed on the surface of the first dielectric layer Al and the first dielectric layer A1 (the upper surface in the figure; the first plane P1). -Fifth conductive layer 12, 13, 14 formed on the back surface (lower surface in the figure; second plane P2) of first conductive layer 11 and first dielectric layer A1 thus formed. , 15, the second dielectric layer A2, the sixth and seventh conductor layers 16, 17, formed on the back surface (the lower surface in the figure; the third plane P3) of the second dielectric layer A2. The eighth to eleventh conductor layers 18, 19, 20 formed on the back surface (the lower surface in the figure; fourth plane P4) of the third dielectric layer A3 and the third dielectric layer A3. , 21, the fourth dielectric layer A4, and the twelfth conductive layer 22 formed on the back surface (the lower surface in the figure; fifth plane P5) of the fourth dielectric layer A4, in this order. Are laminated. In this case, the second to fourth conductor layers 12 14 are arranged in parallel with each other with the third conductor layer 13 as a center, and the respective end portions located on the center side of the first dielectric layer A1. Are connected to the fifth conductor layer 15. The end of the sixth conductor layer 16 located on the center side of the second dielectric layer A2 is connected to the seventh conductor layer 17. The eighth to tenth conductor layers 18 to 20 are arranged in parallel with each other with the ninth conductor layer 19 as a center, and each end located on the center side of the third dielectric layer A3 has an eleventh end. Connected to the conductor layer 21. [0029] The first conductor layer 11 is disposed at a position facing the second to fourth conductor layers 12 to 14 with the first dielectric layer Al interposed therebetween. The sixth conductor layer 16 faces the second and fourth conductor layers 12-14 with the second dielectric layer A2 interposed therebetween, and the eighth to tenth layers with the third dielectric layer A3 interposed therebetween. It is disposed at a position facing the conductor layers 18-20. The seventh conductor layer 17 faces the fifth conductor layer 15 with the second dielectric layer A2 interposed therebetween, and faces the eleventh conductor layer 21 with the third dielectric layer A3 interposed therebetween. It is arranged. The twelfth conductor layer 22 is provided at a position facing the eighth to tenth conductor layers 18-20 with the fourth dielectric layer A4 interposed therebetween. The conductor layers 12-14 on the second plane P2 are formed in the same shape as the conductor layers 18-20 on the fourth plane P4, and are formed on the third plane P3. It faces each conductor layer 18-20 with the sixth conductor layer 16 formed therebetween. The fifth conductor layer 15 on the second plane P2 is formed in the same shape as the conductor layer 21 on the fourth plane P4, and the seventh conductor layer 15 formed on the third plane P3 is formed. It faces the conductor layer 21 with the layer 17 interposed.

As shown in FIGS. 1 and 2, the first conductor layer 11 and the second to fifth conductor layers 12, 13, 14, and 15 formed on the second plane P2 A plurality of conductors (metalized through holes or via holes) penetrating through the first dielectric layer A1 and arranged along three sides of the first conductive layer 11 (three sides inside the multilayer PC). ) Conducted with each other by TH. The sixth conductor layer 16 and the seventh conductor layer 17 extend along the periphery of the sixth conductor layer 16 excluding the portion facing the tip of the input line 2 and penetrate the second dielectric layer A2. The second, fourth, and fifth conductor layers 12, 14, and 15 are electrically connected to each other by the plurality of conductors TH arranged. Further, as shown in FIG. 2, the eighth, tenth, and eleventh conductor layers 18, 20, and 21 are formed of a conductor TH disposed between the second plane P2 and the third plane P3. The plurality of conductors TH arranged in the same manner are electrically connected to the periphery of the sixth and seventh conductor layers 16 and 17. The twelfth conductor layer 22 and the eighth to eleventh conductor layers 18, 19, 20, 21 formed on the fourth plane P4 penetrate the fourth dielectric layer A4 and The conductor layers 22 are electrically connected to each other by a plurality of conductors TH arranged along three sides (three sides inside the multilayer substrate PC). In this case, the first conductor layer 11, the second conductor layer 12, and the second conductor layer 12, which are mutually conducted by the conductors TH disposed on the respective dielectric layers A1 to A4. The fourth to eighth conductor layers 14 to 18 and the tenth to twelfth conductor layers 20 to 22 have at least one of them grounded, and each of them is defined at the ground potential to form a ground electrode. I do. Of these ground electrodes, the seventh conductor layer 17 corresponds to one of the first and second ground electrodes (second ground electrode) of the present invention, and the fifth conductor layer 15 corresponds to the fifth conductor layer. It corresponds to the other (first ground electrode) of the first and second ground electrodes in the invention. Further, the eleventh conductor layer 21 corresponds to a third ground electrode in the present invention.

The conductors TH arranged (arranged) on each of the dielectric layers A1 to A4 have an interval of a predetermined value or less (for example, 1Z4 or less of the wavelength of the electromagnetic wave) so that the propagating electromagnetic wave does not leak. It functions as a pseudo conductor wall. Note that the second conductor layer 12 and the fourth conductor layer 14 provided with the third conductor layer 13 interposed therebetween, and the eighth conductor layer 18 provided with the ninth conductor layer 19 interposed therebetween. And the tenth conductor layer 20 also constitutes a part of the pseudo conductor wall together with the conductors TH connected thereto.

 [0032] The input line 2 is constituted (arranged) by the third conductor layer 13 formed on the same layer as the fifth conductor layer 15, and is connected to each conductor via the dielectric layers Al and A2. Sandwiched between layers 11, 16 and a pair of pseudo conductor walls composed of second and fourth conductor layers 12, 14 and a plurality of conductors TH connected to these conductor layers 12, 14 Thus, a coplanar line for transmitting TEM mode electromagnetic waves is formed. In this case, the input line 2 is connected to the waveguide B1 to input an electromagnetic wave to the waveguide B1. In addition, the fifth conductor layer 15 and the seventh conductor layer 17 which are disposed to face each other with the second dielectric layer A2 interposed therebetween, and a plurality of conduction layers for conducting these conductor layers 15 and 17 are provided. The region surrounded by the conductor wall composed of the body TH constitutes the waveguide B1 (the first waveguide in the present invention) that propagates the TE mode electromagnetic wave. Further, inside the waveguide B1, a plurality (two in this example) of conductors TH1 which are provided through the second dielectric layer A2 and conduct the respective conductor layers 15 and 17 are provided. Are arranged. As a result, the waveguide B1 has a configuration in which two regions partitioned by the conductors TH1 are provided therein, and the region on the input line 2 side constitutes the resonator 3, and the other region Constitute the resonator 4.

Similarly, a seventh conductor layer disposed to face each other across the third dielectric layer A3 The region surrounded by the 17th and 11th conductor layers 21 and the conductor wall composed of a plurality of conductors TH that conduct the conductor layers 17 and 21 is a waveguide type that propagates TE mode electromagnetic waves. A waveguide B2 (a second waveguide of the present invention) is formed. Further, inside the waveguide B2, a plurality (two in this example) of conductors are provided penetrating through the third dielectric layer A3 and conducting each of the conductor layers 17, 21. TH2 is provided. Accordingly, the waveguide B2 has a configuration in which two regions defined by the conductors TH2 are provided therein, and the region on the ninth conductor layer 19 side forms the resonator 6, while the other region forms the resonator 6. This region constitutes the resonator 5. Further, the resonators 4 and 5 which are positioned above and below each other in the stacking direction of the multilayer substrate PC are connected to a coupling window (for example, a magnetic coupling window) provided in the seventh conductor layer 17 (that is, the H plane). ) Are connected to each other through 31). In this case, the coupling window 31 is formed as an H-plane coupling window, for example. The output line 7 is constituted (arranged) by a ninth conductor layer 19 formed on the same layer as the eleventh conductor layer 21, and via each dielectric layer A3, A4, , 22 and the eighth and tenth conductor layers 18, 20 and a pair of pseudo conductor walls composed of a plurality of conductors TH connected to these conductor layers 18, 20. Therefore, it is formed on a coplanar line that transmits TEM mode electromagnetic waves. In this case, the output line 7 is connected to the waveguide B2 and outputs an electromagnetic wave from the waveguide B2. Each of the conductor layers 11 and 22 has, as an example, the area required for covering the second and fourth conductor layers 12 and 14 (the eighth and tenth conductor layers 18 and 20). Although it is formed as described above, it is sufficient if the area is formed to be at least larger than this area. For example, the area can be formed so as to cover the entire area of the first plane P1 and the fifth plane P5 shown in FIG. As described above, along the stacking direction of the multilayer substrate PC, the input line 2 is stacked above the output line 7, the resonator 3 is stacked on the resonator 6, and the resonator 5 is stacked on the resonator 5. The filter 1 is laminated so as to overlap with each other with the seventh conductor layer 17 shared along the laminating direction of the multilayer board PC and the length direction (input line). The ends (right end in FIGS. 1 and 2) on the same side along the path 2 and the output line 7 (in the direction parallel to the length direction of the output line 7) are closed by conductor walls of the conductor TH. A waveguide type waveguide B1 and a waveguide type waveguide B2 are provided, and the respective waveguide type waveguides Bl and B2 are connected to each other at the ends through a coupling window 31. By folding type as a whole Is formed as a waveguide type waveguide. In this filter 1, the two waveguides Bl and B2 are formed substantially plane-symmetric with respect to the third plane P3 as a reference plane.

 Next, the operation of the filter 1 will be described with reference to FIGS. In FIG. 3, for the sake of simplicity, a part of the conductors TH and the conductor layers 12, 14, 18, and 20 constituting the pseudo conductor wall described above are omitted from illustration. I have.

 [0036] In this filter 1, as shown in the figure, when the TEM mode electromagnetic wave W1 is input to the input line 2, the electromagnetic wave W1 is input to the resonator 3 as the TE mode electromagnetic wave W2. Next, the electromagnetic wave W2 is propagated to the resonator 4 via a gap between the conductors TH1 and TH1 functioning as a coupling window. Thereafter, the electromagnetic wave W2 propagates through the coupling window 31 to the resonator 5 and further propagates through the gap between the conductors TH2 and TH2 functioning as the coupling window to the resonator 6, and then the TEM. It is output from the output line 7 as the mode electromagnetic wave W3. At this time, in each of the resonators 3, 4, 5, and 6, only the electromagnetic wave W2 in the resonance frequency band according to the structure passes, and the electromagnetic waves outside the resonance frequency band are reflected to the input side. Therefore, the filter 1 functions as, for example, a band-pass filter (BPF) having characteristics as shown in FIG. In FIG. 5, the solid line indicates the transmission characteristic of the electromagnetic wave, and the broken line indicates the reflection characteristic of the electromagnetic wave. This is the same in FIG. 7 described later.

As described above, according to the filter 1, the conductive layers 15, 17 and the conductive layers 15, 17 disposed opposite to each other with the second dielectric layer A2 interposed therebetween are made conductive. The waveguide B1 surrounded by the plurality of conductors TH, the conductor layers 17, 21 disposed opposite to each other with the third dielectric layer A3 interposed therebetween, and the conductor layers 17, 21 The waveguide-type waveguide B2 surrounded by a plurality of conductors TH that conduct between them is laminated along the lamination direction of the multilayer substrate PC, and both waveguide-type waveguides Bl are connected through the coupling window 31. , B2 are connected to each other at the end in the same direction, so that a plurality of (two in this filter 1) waveguide waveguides Bl, B2 overlap each other in a plan view state. Type waveguide can be formed. Therefore, since the waveguides Bl and B2 overlap, the conventional waveguides Bl and B2 are arranged in a plane along the direction orthogonal to the lamination direction of the multilayer substrate PC. Compared to the configuration, the area (when the force in the stacking direction is viewed) of the filter 1 ) Can be made sufficiently small (about half). Further, according to the filter 1, since the input line 2 and the output line 7 are formed in the multilayer substrate PC, a filter having an input / output unit can be constituted by the multilayer substrate PC alone.

 [0038] The present invention is not limited to the configuration described above. For example, in the above-described filter 1, an example is given in which a five-layer multilayer substrate PC is used and two waveguide waveguides Bl and B2 are laminated inside the multilayer substrate PC along the lamination direction of the multilayer substrate PC. As described above, three or more waveguide-type waveguides are laminated in the lamination direction using a multilayer substrate PC with six or more layers, and each waveguide-type waveguide is connected. A configuration in which the windows are connected to each other may be employed.

In the above configuration, only the electromagnetic wave W2 of the electromagnetic wave W1 input from the input line 2 that has passed through the coupling window 31 is output from the output line 7 (that is, the electromagnetic wave W1 For example, as shown in a filter 1A in FIG. 6, a region sandwiched between the input line 2 and the output line 7 in the sixth conductor layer 16 as in the filter 1A shown in FIG. It is also possible to adopt a configuration in which another coupling window 32 is provided at another portion) and the input line 2 and the output line 7 are coupled to each other via the coupling window 32. That is, a filter having a plurality of propagation paths (so-called multipath) can be configured. By employing this configuration, of the electromagnetic wave W1 input from the input line 2, the waveguide W1 passes through the coupling window 31 and the waveguide W2 without passing through the coupling window 32. A phase difference between the electromagnetic wave W2 propagating to the output line 7 and the electromagnetic wave W4 passing through the coupling window 32 and propagating to the output line 7 can be generated. This phase difference can be adjusted by adjusting the formation position. Therefore, by setting the phase difference between these electromagnetic waves W2 and W4 to 180 degrees, a part of each of electromagnetic waves W2 and W4 can be canceled out, so that an attenuation pole can be formed in filter 1. Figure 7 shows the frequency characteristics of the filter 1A having this attenuation pole. As is clear from the frequency characteristics shown in the figure, the arrangement of the coupling window 32 together with the coupling window 31 causes an attenuation pole to be formed on the lower frequency side of the pass frequency band, and the filter in which only the coupling window 31 is formed. Compared with the frequency characteristic of 1 (see Fig. 5), the falling force S of attenuation on the lower frequency side of the pass frequency band can be adjusted more steeply. Therefore, by appropriately setting the formation position and size of the coupling window 32, it is possible to realize a filter having a desired frequency characteristic. it can. It should be noted that the other coupling window 32 can be provided at a position other than the above-described portion. For example, as in a filter 1B shown in FIG. 8, a coupling window 32 can be provided in a region between the resonator 3 and the resonator 6 in the seventh conductor layer 17. Further, two or more coupling windows 32 can be provided. 6 and 8, the same components as those of the filter 1 are denoted by the same reference numerals, and redundant description is omitted.

 [0040] In the above configuration, the waveguides Bl and B2 are connected to the seventh conductor layer 17 (each waveguide-type waveguide) at the end in the same direction along the length direction. The configuration in which the coupling window 31 is directly connected via the coupling window 31 formed in the conductor layer shared by Bl and B2 has been described. Instead of the configuration in which the coupling window 31 is formed in the seventh conductor layer 17, FIGS. Like the filter 1C shown in the drawing, a resonator 33 is provided at the end in the same direction along the longitudinal direction of the waveguides Bl and B2, and the two waveguides are provided via the resonator 33. The waveguides Bl and B2 may be connected to each other. Since the basic configuration of the filter 1C is almost the same as that of the filter 1, the same components are denoted by the same reference numerals, and redundant description will be omitted. In this filter 1C, the fifth conductor layer 15 and the eleventh conductor layer B1 and B2 are arranged in front of the ends in the same direction (right ends in FIGS. 9 and 10) of the waveguides B1 and B2. The conductor layer 21 is further extended in the same direction, and is extended along the periphery of each extension portion (excluding the edges in contact with the resonators 4 and 5) of the fifth conductor layer 15 and the eleventh conductor layer 21. By disposing a plurality of conductors TH for conducting between the extending portions, each extending portion in the fifth conductor layer 15 and the eleventh conductor layer 21 and a conductor wall formed of the plurality of conductors TH are provided. Thus, the resonator 33 is configured. In this case, the thickness of the resonator 33 is equal to the sum of the thicknesses of the resonators 4 and 5. In addition, a plurality of conductors TH3 and TH4 are provided at each boundary between the resonator 33 and each of the resonators 4 and 5, and the resonator 33 and each of the resonators 4 and 5 function as a coupling window. The conductors TH3 and TH4 are connected to each other via a gap between them.

In the filter 1C, as shown in FIG. 10, when the electromagnetic wave W1 in the TEM mode is input to the input line 2, the electromagnetic wave W1 is input to the resonator 3 as the electromagnetic wave W2 in the TE mode. Next, the electromagnetic wave W2 propagates through the gap between the conductors TH1 functioning as the coupling window to the resonator 4 and further propagates through the gap between the conductors TH3 functioning as the coupling window to the resonator 33. You. The electromagnetic wave W2 propagated to the resonator 33 functions as a coupling window Propagated to the resonator 5 via the gap between the conductors TH4 and further propagated to the resonator 6 via the gap between the conductors TH2, and then output as the TEM mode electromagnetic wave W3 Output from 7. In this filter 1C as well, although the outer size is increased by the size of the resonator 33 as compared with the filter 1, the waveguides Bl and B2 overlap each other in a plan view, so that the outer shape is sufficiently small. You can dagger.

 [0042] Also in this filter 1C, similarly to filter 1A described above, another coupling window 32 described above is arranged in a region of sixth conductor layer 16 sandwiched between input line 2 and output line 7. (For example, disposed at the position POl), or in the same manner as in the above-described filter 1B, the resonator is sandwiched between the resonator 3 and the resonator 6 in the seventh conductor layer 17. Another coupling window 32 may be provided in the area (for example, provided at position P02). Further, in the filter 1C, another coupling window 32 can be provided in a region between the resonator 4 and the resonator 5 in the seventh conductor layer 17 (for example, provided at a position P03). . By employing at least one of these configurations, it is possible to configure a filter having a plurality of propagation paths (or so-called multipaths) and having an attenuation pole formed based on the filter 1C. it can. With such a configuration, a new attenuation pole can be formed, and as a result, filters having various frequency characteristics can be realized.

 [0043] In the filters 1, 1A, IB, and 1C described above, each waveguide-type waveguide Bl, B2 is provided in the multilayer substrate PC in parallel with the conductor layer. By arranging a waveguide waveguide in the multilayer substrate PC along a direction orthogonal to the direction, a small filter can be formed in the multilayer substrate PC.

 As shown in FIGS. 11 and 12, the filter 1D includes an input line 2, two resonators 41 and 42 forming a waveguide B3, and a resonator 2 forming a waveguide B4 2 It is provided with two resonators 43, 44 and an output line 7, and is formed in a multilayer board (four-layer board as an example) PC1. In the figure, conductors to be described later are omitted in order to facilitate understanding of the description. Also, the same components as those of the filter 1 are denoted by the same reference numerals, and redundant description will be omitted.

As shown in FIG. 12, the multilayer substrate PC1 was formed on the surfaces of the first dielectric layer Al and the first dielectric layer A1 (the upper surface in FIG. 12; the first plane P1). Conductor layer 51, first dielectric The three conductor layers 52, 53, 54, the second dielectric layer A2, and the rear surface of the second dielectric layer A2 formed on the back surface of the layer Al (the lower surface in the figure; the second plane P2) The lower surface in the figure, the three conductor layers 55, 56, 57 formed on the third plane P3), the third dielectric layer A3, and the back surface of the third dielectric layer A3 (the same figure). The lower surface in the middle, where two conductor layers 58 and 59 formed on the fourth plane P4) are stacked in this order. In this case, the conductor layers 51, 52, and 55 have the same planar shape as each other, and are disposed so that the conductor layers 51 and 55 face the conductor layer 52, respectively. . The conductor layers 56 and 57 are disposed on both sides of the conductor layer 55, and their ends are formed on a pair of opposing sides of the conductor layer 55 (in FIG. 11, upper left and lower right diagonal opposing sides). Each is connected to almost the center. The conductor layers 53 and 58 are disposed to face each other, and the conductor layer 56 is disposed between the conductor layers 53 and 58. The conductor layers 54 and 59 are arranged facing each other, and the conductor layer 57 is arranged between the conductor layers 54 and 59.

Further, a plurality of conductors (not shown) penetrating the first dielectric layer A1 and conducting the two conductor layers 51, 52 are provided on the respective edges (four sides) of the conductor layers 51, 52, respectively. Are arranged. In addition, the periphery (four sides) of each of the conductor layers 52 and 55 also penetrates through the second dielectric layer A2 except for the portion of the conductor layer 55 where the conductor layers 56 and 57 are connected and the vicinity thereof. A plurality of conductors (not shown) that conduct the two conductor layers 55 and 52 are provided. In addition, the edge of each of the conductor layers 53 and 58 parallel to the length direction of the conductor layer 56 also penetrates through the second dielectric layer A2 and the third dielectric layer A3, and the , 58 are provided with a plurality of conductors (not shown). Similarly, the edge of each of the conductor layers 54 and 59, which is parallel to the length direction of the conductor layer 57, penetrates through the second dielectric layer A2 and the third dielectric layer A3 to form both conductor layers. A plurality of conductors (not shown) for conducting the wires 54 and 59 are provided. Each of these conductors has an interval set to a predetermined value or less (for example, 1Z4 or less of the wavelength of the electromagnetic wave) and functions as a pseudo conductor wall. At least one of the conductor layers 51 to 59 is grounded so that each is defined at a ground potential to form a ground electrode.

As shown in FIGS. 11 and 12, a plurality of conductors TH5 that penetrate the second dielectric layer A2 and conduct the conductor layers 52 and 55 are provided at the center of the conductor layer 55, as shown in FIGS. Length of layers 56 and 57 Are arranged in a line along a direction perpendicular to the direction. Each conductor TH5 also functions as a pseudo conductor wall with the interval set to a predetermined value or less (for example, 1Z4 or less of the wavelength of the electromagnetic wave). As a result, the region surrounded by the conductor wall formed by the conductor layer 52, the conductor layer 55, and the conductor formed on the periphery of the two conductor layers 52, 55 is divided into two by the conductor TH5, so that the inside of this region is Thus, a resonator 41 and a resonator 44 are formed. On the other hand, at the center of the conductor layer 51, as shown in the figure, a plurality of (two as an example) conductors penetrating the first dielectric layer A1 and conducting the conductor layers 51 and 52 are provided. TH6 is arranged in a line along a direction perpendicular to the length direction of the conductor layers 56 and 57. As a result, the region surrounded by the conductor wall formed by the conductor layers 51 and 52 and the conductor formed on the periphery of the two conductor layers 51 and 52 is divided into two by the conductor TH6, so that the region A resonator 42 and a resonator 43 are formed. In this case, the gap between the conductors TH6 functions as a coupling window connecting the two resonators 42 and 43. In addition, the resonators 41 and 42 are connected via a coupling window 60 formed in a portion of the conductor layer 52 that is shared with each other, thereby forming one waveguide-type waveguide B3 as a whole. Further, the resonators 43 and 44 are connected via a coupling window 61 formed at a portion of the conductor layer 52 that is shared with each other, and constitute another waveguide type waveguide B4 as a whole. . Therefore, each of the waveguide waveguides B3 and B4 is connected to the resonators 42 and 43 located at the ends in the same direction along the lamination direction (upward side in FIG. 12). They are connected via gaps (coupling windows formed on the conductor wall in the present invention). In this filter 1D having the above components, the two waveguides B3 and B4 are formed substantially plane-symmetric with respect to the surface on which the conductors TH5 and TH6 are formed.

 [0048] The input line 2 is constituted by the conductor layer 56, and is also constituted by the conductor layers 53, 58 and the conductor for conducting the conductor layers 53, 58 through the dielectric layers A2, A3. It is formed as a coplanar line that transmits TEM mode electromagnetic waves by being sandwiched between a pair of pseudo conductor walls. The output line 7 is composed of a conductor layer 57 and a pseudo conductor composed of the conductor layers 54 and 59 and the conductors that conduct the conductor layers 54 and 59 through the dielectric layers A2 and A3. By being sandwiched between a pair of conductive walls, like the input line 2, a coplanar line for transmitting TEM mode electromagnetic waves is formed.

[0049] In this filter 1D, as shown in Figs. When the electromagnetic wave W1 is input to the path 2, the electromagnetic wave W1 is input to the resonator 41 as a TE mode electromagnetic wave W2. Next, the electromagnetic wave W2 propagates through the coupling window 60 to the resonator 42, and further propagates through the gap between the conductors TH6 to the resonator 43. After that, the electromagnetic wave W2 is propagated to the resonator 44 via the coupling window 61, and then output from the output line 7 as a TEM mode electromagnetic wave W3.

As described above, according to the filter 1D, a pair of waveguides B3 and B4 can be formed in the multilayer substrate PC1 along the direction orthogonal to each of the conductor layers 51 to 59. it can. For this reason, when the respective conductor layers 51 to 59 are viewed in plan, the respective waveguides B3 and B4 cannot be overlapped with each other, but they are shared with the resonator 41 forming the waveguide B3. The resonator 42 can be overlapped, and the resonator 43 and the resonator 44 constituting the waveguide B4 can be overlapped. Accordingly, the outer shape of each of the waveguides B3 and B4 in a plan view can be reduced, so that the filter 1D can be sufficiently reduced in size.

 Further, based on the filter 1D, as shown in FIG. 13, a coupling window 62 is formed in the conductor wall formed by the conductor TH5 by removing a part of the conductor TH5. Accordingly, a filter 1E having a plurality of propagation paths (so-called multipaths) similar to the filters 1A and 1B can be configured.

Further, based on the filter 1D, as shown in FIG. 14, each end of the waveguide-type waveguides B3 and B4 in the same direction along the laminating direction (upper end in FIG. 14) In this case, another resonator 63 is disposed with each of the resonators 42 and 43 and the conductor layer 51 being shared, so that a pair of waveguides B3 and B4 are folded back through the resonator 63. It is also possible to realize the filter 1F having a configuration in which the filters 1F are connected in a state where the filters 1F are connected. Note that the same components as those of the filter 1D are denoted by the same reference numerals, and redundant description will be omitted. In this case, a multilayer substrate PC2 is used as a five-layer substrate, and the resonator 63 includes the conductor layer 51 and the conductor layer 51 on the upper surface (plane PO) of the dielectric layer AO laminated on the dielectric layer A1. And a plurality of conductors (not shown) formed around the periphery of the conductor layer 64 so as to penetrate through the conductor layer 64 and the dielectric layer AO. ). In addition, a common part of the resonator 42 and the resonator 63 in the conductor layer 51 and a common part of the resonator 43 and the resonator 63 Are formed with coupling windows 65 and 66, respectively.

 [0053] In this filter 1F, as shown in the figure, the TE mode electromagnetic wave W2 in the resonator 41 passes through the coupling window 60, the resonator 42, the gap between the conductors TH6, the resonator 43, and the coupling window 61. Via the coupling window 60, the resonator 42, the coupling window 65, the resonator 63, the coupling window 66, the resonator 43, and the coupling window 61 to the resonator 44. Propagate two paths. Therefore, the filter 1F functions as a filter having a plurality (two) of propagation paths (so-called multipath). Further, in the filter 1F, a third propagation path can be formed by forming a coupling window in the conductor TH5. On the other hand, by setting the interval between the conductors T H5 and TH6 to, for example, 1Z4 or less of the wavelength of the electromagnetic wave W2, a filter having no multipath based on the filter 1F can be realized. .

 According to the filter 1F, the waveguide type waveguides B3 and B4 cannot be overlapped with each other when the conductor layer 64 (the ground electrode) is viewed in a plan view, but the filter is in a state in a plan view. The outer shape of each waveguide type waveguide B3, B4 itself can be reduced sufficiently. Furthermore, since the waveguides B3 and B4 can be included in the area occupied by the resonator 63 when the conductor layer 64 is viewed in a plan view, the resonator 63 is provided. However, it is possible to sufficiently reduce the size of the filter 1F in a state where the conductor layer 64 (ground electrode) is viewed in a plan view, and to sufficiently reduce the size.

 In the above-described filters 1, 1A, IB, 1C, ID, IE, and 1F, an example has been described in which each waveguide-type waveguide Bl, B2, B3, and B4 is configured by two resonators. Needless to say, each of the waveguide type waveguides B1 to B4 can be constituted by three or more resonators. Also, an example has been described in which each of the waveguide waveguides Bl and B2 is composed of the same number of resonators. For example, the waveguide waveguide B1 is composed of two resonators, and Each waveguide-type waveguide Bl, B2 can be composed of a different number of resonators, for example, the waveguide B2 is composed of three resonators. Similarly, each of the waveguides B3 and B4 can be configured with a different number of resonators. Further, in an example in which the input line 2 and the output line 7 are formed by a coplanar line, the above-described force is formed by a microstrip line or a strip line.

Claims

The scope of the claims  [1] A multi-layer substrate surrounded by a conductor wall formed by first and second ground electrodes disposed to face each other with a dielectric layer interposed therebetween and a conductor that conducts between the ground electrodes A first waveguide type waveguide formed in  One of the first and second ground electrodes, a third ground electrode disposed to face the one ground electrode with a dielectric layer interposed therebetween, and the one ground electrode and the third ground electrode. A second waveguide type formed along the first waveguide type waveguide in the multi-layer substrate surrounded by a conductor wall formed by a conductor that conducts between third ground electrodes. And a waveguide,  The respective waveguide type waveguides are closed at respective ends in the same direction along the length direction, and at each of the ends through a coupling window provided in the one ground electrode. , Connected to! Filter. [2] Each of the waveguide type waveguides is connected to each other via another coupling window provided on the one ground electrode at the other portion except for the end portion on the same direction side! The filter according to claim 1, wherein [3] A multi-layer structure surrounded by a conductor wall constituted by first and second ground electrodes disposed opposite to each other with a dielectric layer interposed therebetween and a conductor for conducting between the ground electrodes. A first waveguide type waveguide formed in the layer substrate;  One of the first and second ground electrodes, a third ground electrode disposed to face the one ground electrode with a dielectric layer interposed therebetween, and the one ground electrode and the third ground electrode. A second waveguide type formed along the first waveguide type waveguide in the multi-layer substrate surrounded by a conductor wall formed by a conductor that conducts between third ground electrodes. A waveguide; A conductor wall formed by a conductor between the other of the first and second ground electrodes, the third ground electrode, and a conductor that conducts between the other ground electrode and the third ground electrode; A resonator formed in the multilayer substrate so as to be surrounded and disposed at an end in the same direction along the length direction in each of the waveguide type waveguides. Each of the waveguide type waveguides is a filter in which ends in the same direction are connected to each other via the resonator.  4. The filter according to claim 3, wherein each of the waveguide type waveguides is connected to each other via a coupling window provided on the one ground electrode. [5] The electromagnetic wave is disposed on the same layer as the other ground electrode of the first and second ground electrodes, and is connected to the first waveguide to transmit an electromagnetic wave to the first waveguide. An input line for input to the tubular waveguide;  The second ground electrode is disposed on the same layer as the third ground electrode, facing the input line across the one ground electrode, and connected to the second waveguide. An output line for outputting the electromagnetic wave from the waveguide type waveguide,  2. The filter according to claim 1, wherein the input line and the output line are coupled to each other via a coupling window formed in the one ground electrode. [6] The electromagnetic wave is disposed on the same layer as the other ground electrode of the first and second ground electrodes and connected to the first waveguide type waveguide to transmit electromagnetic waves to the first waveguide. An input line for input to the tubular waveguide;  The second ground electrode is disposed on the same layer as the third ground electrode, facing the input line across the one ground electrode, and connected to the second waveguide. An output line for outputting the electromagnetic wave from the waveguide type waveguide,  3. The filter according to claim 2, wherein said input line and said output line are coupled to each other via a coupling window formed in said one ground electrode. [7] The electromagnetic wave is disposed on the same layer as the other ground electrode of the first and second ground electrodes and connected to the first waveguide type waveguide to transmit an electromagnetic wave to the first waveguide. An input line for input to the tubular waveguide;  The second ground electrode is disposed on the same layer as the third ground electrode, facing the input line across the one ground electrode, and connected to the second waveguide. An output line for outputting the electromagnetic wave from the waveguide type waveguide, 4. The filter according to claim 3, wherein said input line and said output line are coupled to each other via a coupling window formed in said one ground electrode. [8] The first and second ground electrodes are disposed on the same layer as the other ground electrode, and are connected to the first waveguide to transmit an electromagnetic wave to the first waveguide. An input line for input to the tubular waveguide;  The second ground electrode is disposed on the same layer as the third ground electrode, facing the input line across the one ground electrode, and connected to the second waveguide. An output line for outputting the electromagnetic wave from the waveguide type waveguide,  5. The filter according to claim 4, wherein said input line and said output line are coupled to each other via a coupling window formed in said one ground electrode. [9] A pair of waveguide-type waveguides is provided in a multilayer substrate configured by alternately laminating a plurality of ground electrodes and dielectric layers,  Each of the waveguide-type waveguides includes a pair of ground electrodes disposed to face each other with the dielectric layer interposed therebetween, and a conductor wall configured by a conductor that conducts between the pair of ground electrodes. Are formed by stacking a plurality of resonators formed by enclosing the multilayer substrate in the laminating direction of the multilayer substrate, and are arranged in parallel with each other while sharing the conductor wall located therebetween. And at the ends in the same direction along the lamination direction, the resonators are connected to each other via a coupling window formed in the conductor wall located therebetween. Filter. [10] The resonators other than the resonators at the respective ends that constitute the respective waveguide waveguides are connected to each other via a coupling window formed in the conductor wall located therebetween. 10. The filter according to claim 9, wherein the filter is connected. [11] A pair of waveguides is provided in a multilayer substrate configured by alternately stacking a plurality of ground electrodes and dielectric layers, and the multilayer substrate in each of the waveguides is provided. Resonators are arranged at each end on the same direction side along the stacking direction of  The resonator is formed so as to be surrounded by a pair of ground electrodes disposed to face each other with the dielectric layer interposed therebetween, and a conductor wall formed by a conductor that conducts between the pair of ground electrodes. , Each of the waveguide-type waveguides is constituted by a pair of ground electrodes disposed to face each other with the dielectric layer interposed therebetween, and a conductor that conducts between the pair of ground electrodes. A plurality of resonators formed by being surrounded by a plurality of conductor walls arranged in the laminating direction of the multilayer substrate, and in parallel with each other while sharing the conductor walls located therebetween. And the resonators are connected to each other by being connected to each other via the resonators provided at the respective ends.  The resonators constituting each of the waveguide type waveguides are connected to each other via a coupling window formed in the conductor wall located therebetween. 12. The filter according to claim 11, wherein: