JPH11186805A - Coaxial type dielectric filter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coaxial type dielectric filter that reduces an arrangement space reduction in the case of being integrated with an electronic circuit or the like within a package and provides a desired characteristic. SOLUTION: This coaxial type dielectric filter is provided with a cut-off waveguide 1 with a bent part 10, two coaxial type dielectric resonators 21, 22 that are arranged in the waveguide 1 holding the bent part inbetween, a rod-shaped input side antenna 32 that is inserted and arranged in an input side inner conductor of one of the coaxial type dielectric resonator via a sleeve 51 made of polytetrafluoroethylene and a rod-shaped output side antenna 42 that is inserted and arranged in an output side inner conductor of the other coaxial dielectric resonator via a sleeve 52. Furthermore, coupling reinforcing members 61, 62 that reinforce electric coupling between the both coaxial type dielectric resonators are provided respectively to adjacent side ends between the coaxial dielectric resonators adjacent to each other holding the bent part inbetween. Since the cut-off waveguide with the bent part is applied for the coaxial type dielectric filter in place of a straight line structure of a conventional filter, the length size of the filter is reduced and the action of the coupling reinforcing members enhances the electric coupling.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coaxial dielectric filter (a so-called timing extraction filter) used for signal regeneration and clock signal extraction in a regenerative repeater for optical communication, and more particularly, to an electronic package in a package. The present invention relates to an improvement of a coaxial dielectric filter capable of reducing an arrangement space when integrated with circuits and the like.

[0002]

2. Description of the Related Art FIG. 5 is an equivalent circuit diagram of a typical dielectric filter using a coaxial dielectric resonator. FIG. 6 is a diagram showing a conventional coaxial type dielectric filter using a capacitor. It is a top view showing the structure of a dielectric filter. In a typical coaxial dielectric filter, as shown in an equivalent circuit diagram of FIG.
Components such as capacitors (C1, C2, C3) (or inductors) are provided between the coaxial dielectric resonators (between stages) and to obtain electrical coupling between the coaxial dielectric resonators and the output connector. Have been placed. In the coaxial dielectric filter according to the conventional example, the capacitor is formed on a substrate such as alumina by a technique such as thick-film printing in order to obtain a desired electrical coupling, and as shown in FIG. )
Connected using connection leads. In FIG. 6, reference symbol a denotes a coaxial dielectric resonator, b denotes an input / output capacitor,
c is an interstage capacitor, d is a metal case provided with a recessed housing part d 'which constitutes a part of the cutoff waveguide, e is an input connector, f is an output connector, and g is a capacitor connection lead. Each is shown.

When a coaxial dielectric filter having a narrow pass band is to be manufactured as a dielectric filter, a capacitor having an extremely small capacitance is required. In the above-mentioned electrical coupling method using a substrate such as alumina, since it is extremely difficult to realize a capacitor or the like having a small capacitance, there is a disadvantage that a coaxial dielectric filter having a narrow pass bandwidth cannot be mass-produced. Was.

Therefore, the present applicant has already proposed a coaxial dielectric filter in which the structure is simplified by adopting a new electrical coupling method which does not use components such as capacitors (Japanese Patent Laid-Open No. Hei 8 (1996) -1996). -88504).

That is, this coaxial dielectric filter is
As shown in FIGS. 7 (A) and 7 (B), a linear cut-off conductor formed of a storage part d 'provided in a metal case d and a metal lid d "for closing the open side of the storage part d'. A waveguide, and two coaxial dielectric resonators a, which are coaxially arranged at a distance in the cut-off waveguide and provided with an outer conductor and an inner conductor on the outer peripheral surface and the inner peripheral surface of the cylindrical main body, a, and one end is inserted into an input-side inner conductor of a coaxial dielectric resonator a, one end of which is supported by an input-side connector e fixed to the input side of the cutoff waveguide and arranged on the input side. Rod-shaped input antenna i
One end is supported by an output connector f fixed to the output side of the cutoff waveguide, and the other end is inserted into the output-side inner conductor of the coaxial dielectric resonator a disposed on the output side. The main part was constituted by the rod-shaped output-side antenna j.

In this coaxial dielectric filter, the electrical coupling corresponding to C1 and C3 shown in FIG. 5 is made by connecting the other end of a rod-shaped input antenna i whose one end is supported by the input connector e to the other end of the coaxial dielectric filter. By inserting it into the input-side inner conductor of the dielectric resonator a, the output-side connector f
The other end of the rod-shaped output-side antenna j, one end of which is supported, is inserted into the output-side inner conductor of the coaxial dielectric resonator a. The amount of electrical coupling can be changed by changing the insertion amount of the rod-shaped input antenna i and the output antenna j inserted in the inner conductor of the coaxial dielectric resonators a and a. Since the facing area between the inner conductor of the dielectric resonators a, a and each antenna i, j changes, it can be changed. Therefore, by changing the insertion amount of the rod-shaped input antenna i and the output antenna j inserted into the inner conductor of each coaxial dielectric resonator a, a, the electric coupling amount (capacitance) C1,
C3 can be adjusted.

The electric coupling corresponding to C2 shown in FIG. 5 is performed when the coaxial dielectric resonators a and a are disposed in the cut-off waveguide, and the opposing sides of the coaxial dielectric resonators a and a are arranged. Can be given by increasing the distance between the open surfaces. The amount of electrical coupling is exponentially attenuated by increasing the distance between the coaxial dielectric resonators a, a in the cutoff waveguide, and the opposing coaxial dielectric resonators a, By changing the distance a, the amount of electric coupling (capacitance and / or inductance) C2 between the coaxial dielectric resonators a can be adjusted.

As described above, according to the coaxial dielectric filter developed by the present applicant, the structure of the filter can be simplified since a new electrical coupling method that does not use components such as a capacitor is employed. Since the number of points can be reduced, a narrow-band coaxial dielectric filter can be easily and inexpensively manufactured.

The coaxial dielectric filter developed by the present applicant has the advantages described above,
Since at least two coaxial dielectric resonators a and a and a rod-shaped input antenna i and an output antenna j are arranged in a linear cut-off waveguide, their lengths are inevitable. Therefore, there is a certain limit in miniaturizing the coaxial dielectric filter.

For this reason, when components such as the above-mentioned communication device are integrated in a package together with, for example, an electronic circuit, and mounted on the device, the size of the coaxial dielectric filter is reduced due to the arrangement space. It had unforeseen drawbacks.

In order to solve this problem, the inventor of the present invention provided a bent portion in a conventional blocking waveguide, tried to reduce the length thereof, and tried to apply the same. That is, as shown in FIG. 8, the above-mentioned coaxial dielectric resonators a and a rod-shaped input-side antenna i and output-side antenna j are arranged in a cut-off waveguide q having a bent portion p. When a coaxial dielectric filter was prototyped and its function was examined in detail, it was found that this coaxial dielectric filter having a bent portion p in the cutoff waveguide q has a conventional coaxial dielectric filter having a linear structure contrary to the initial expectation. It has been found that it can function in substantially the same way as a shaped dielectric filter.

[0012]

By the way, when the set angle of the bent portion p in the cutoff waveguide q was an obtuse angle, there was not much problem. However, as the set angle of the bent portion p became smaller, two problems occurred. The electric coupling between the coaxial dielectric resonators a tends to be weakened, and in an extreme case, there is a problem that it is difficult to obtain the electric coupling.

In this type of coaxial dielectric filter, between the coaxial dielectric resonator a disposed on the input side and the input antenna i, between the two coaxial dielectric resonators a, a And a desired characteristic is realized when the degree of electrical coupling between the coaxial dielectric resonator a and the output side antenna j arranged on the output side is balanced.
If the degree of electrical coupling becomes more difficult to balance as the setting angle of the bent portion p becomes smaller, a coaxial dielectric filter having desired characteristics cannot be obtained.

The coaxial dielectric filter shown in FIG. 8 has a structure in which one coaxial dielectric resonator a is arranged in each of the cutoff waveguides on both sides of the bent portion p. However, there is also a coaxial dielectric filter having a structure in which two or more coaxial dielectric resonators are respectively disposed in the cutoff waveguides on both sides of the bent portion p.

Also in this coaxial dielectric filter, the bent portion p is set between a pair of coaxial dielectric resonators adjacent to each other with the bent portion p interposed therebetween (that is, the corner-side coaxial dielectric resonator). As the angle becomes smaller, it becomes more difficult to obtain electrical coupling between the coaxial dielectric resonators, so that there is a similar problem.

The present invention has been made in view of such a problem, and an object thereof is to provide a coaxial dielectric which can achieve desired characteristics even if the set angle of the bent portion is reduced. To provide a filter.

[0017]

That is, according to the first aspect of the present invention, there is provided a cut-off waveguide having at least one bent portion and a distance between the cut-off waveguides on both sides of the bent portion. At least two coaxial dielectric resonators provided coaxially and having an outer conductor and an inner conductor provided on an outer peripheral surface and an inner peripheral surface of a cylindrical main body; and a coaxial dielectric resonator disposed on an input side. A rod-shaped input-side antenna having one end inserted into the input-side inner conductor, and a rod-shaped output-side antenna having one end inserted into the output-side inner conductor of a coaxial dielectric resonator disposed on the output side. Assuming a coaxial dielectric filter
At least one of the adjacent side ends of the pair of square-side coaxial dielectric resonators adjacent to each other with the bent portion interposed therebetween is formed of a low-loss dielectric material, and is formed between the same-side coaxial dielectric resonators. A connection reinforcing member for strengthening electrical connection is provided.

According to the coaxial dielectric filter according to the first aspect of the present invention, at least one of the adjacent side ends of the pair of square coaxial dielectric resonators adjacent to each other across the bent portion. Since the coupling reinforcing member made of a low-loss dielectric material and strengthening the electrical coupling between the coaxial dielectric resonators on the equiangular side is provided, the set angle of the bent portion in the cutoff waveguide is set. Becomes smaller, even if the electrical coupling between a pair of adjacent angular coaxial dielectric resonators sandwiching the bent portion is weakened due to the set angle,
The weakened portion is compensated for by the coupling reinforcing member, and the strength of the electrical coupling between the square-side coaxial dielectric resonators is adjusted, so that the above-described electrical coupling degree can be balanced. .

In such technical means, the number of the bent portions of the cutoff waveguide is arbitrary, and is appropriately set according to the arrangement space, the space shape, and the like in the package in which the coaxial dielectric filter is incorporated. In other words, when the number of the bent portions is one, the cutoff waveguide has a substantially L-shape, and when the number of the bent portions is two, the cutoff waveguide has a substantially U-shape or a substantially Z-shape. . The number of bending portions and the bending direction in which the cutoff waveguide is formed by bending a three-dimensional space can be selected depending on the use of the coaxial dielectric filter.

Next, the number of coaxial dielectric resonators disposed in the cut-off waveguides on both sides of the bent portion is arbitrary, and an arrangement space in the package in which the coaxial dielectric filter is incorporated. The number is appropriately set according to the shape of the space, the shape of the space, or the required characteristics of the filter.

When a plurality of coaxial dielectric resonators are arranged, from the viewpoint of making it easier to balance the degree of electrical coupling described above, each adjacent coaxial dielectric resonator between linearly arranged coaxial dielectric resonators is used. A structure in which the coupling reinforcing member is provided at the side end may also be adopted. The invention according to claim 2 has been made based on such technical requirements.

That is, the invention according to claim 2 is based on the coaxial dielectric filter according to the invention described in claim 1,
Two or more coaxial dielectric resonators are respectively arranged in each of the cut-off waveguides on both sides of the bent portion, and in each cut-off waveguide, the angular coaxial dielectric resonator and another coaxial dielectric resonator adjacent thereto are disposed. At least one of the adjacent end portions of the coaxial dielectric resonator and at least one of the adjacent end portions between the coaxial dielectric resonators other than the corner coaxial dielectric resonator and other adjacent coaxial dielectric resonators are low. A coupling reinforcing member made of a lossy dielectric material and strengthening electrical coupling between adjacent coaxial dielectric resonators is provided.

Next, according to a third aspect of the present invention, a substantially U-shaped waveguide having two bent portions is applied, and
The present invention relates to an invention that specifies a configuration of a coaxial dielectric filter in which one coaxial dielectric resonator is disposed in a pair of parallel parts and one linear part connecting the parallel parts.

That is, the invention according to claim 3 is based on the premise of the coaxial dielectric filter according to claim 1 of the present invention.
The cut-off waveguide is composed of a substantially U-shaped waveguide composed of a pair of parallel portions and one straight portion connecting these, and each parallel portion and straight portion in this substantially U-shaped waveguide has One coaxial dielectric resonator is disposed, and each adjacent side end between the coaxial dielectric resonator disposed in one parallel portion and the coaxial dielectric resonator disposed in the linear portion; A coaxial dielectric resonator disposed in the linear portion and a coaxial dielectric resonator disposed in the other parallel portion, at each adjacent side end, formed of a low-loss dielectric material and adjacent to the coaxial dielectric resonator; A coupling reinforcing member for enhancing electrical coupling between the dielectric resonators is provided.

According to the coaxial dielectric filter according to the third aspect of the present invention, the cut-off waveguide has a substantially U-shaped waveguide composed of a pair of parallel portions and one linear portion connecting the parallel portions. The arrangement of the coaxial dielectric resonators arranged in a pair of parallel parts has a parallel relationship with each other. By arranging the input side antenna on the body resonator side and arranging the output side antenna on the other coaxial dielectric resonator side, the input side and the output side can be arranged on the same side. It is possible to greatly improve the degree of freedom in circuit design in a package on which the type dielectric filter is mounted.

In this technical means, as the coaxial dielectric resonator incorporated in the cutoff waveguide, a resonator having a high dielectric constant is preferably applied from the viewpoint of miniaturization of the filter. Many materials have large loss at high frequency.

Since the loss of the coaxial dielectric resonator appears as the loss of the filter, it is preferable to select the material in consideration of the characteristic value of the target filter. The main part of the coaxial dielectric resonator applied in the present invention includes a cylindrical main body, and outer and inner conductors provided on the outer peripheral surface and the inner peripheral surface of the cylindrical main body. Things.

Here, as a coupling reinforcing member to be inserted into an end portion of each coaxial dielectric resonator, for example, an insertion portion in an inner conductor of the coaxial dielectric resonator, a material having a small loss at a high frequency, for example, In principle, if it is composed of a low-loss dielectric material such as a fluororesin represented by polytetrafluoroethylene or an acetal copolymer represented by "Duracon" (trade name of Celanese Corporation) Is optional. However, in consideration of the workability of inserting the inner conductor into the insertion site, a coupling reinforcing member having a flange portion locked at the entrance of the inner conductor is advantageous. The invention according to claim 4 relates to the invention in which the configuration of the coupling reinforcing member is specified for such a reason.

That is, a fourth aspect of the present invention is based on the coaxial dielectric filter according to the first, second or third aspect of the present invention, wherein the coupling reinforcing member includes a substantially disc-shaped flange and a center portion thereof. And a convex portion protruding outward and fitted into the inner conductor of the coaxial dielectric resonator.

Next, a fifth aspect of the present invention is the same as the third aspect of the invention, wherein a substantially U-shaped waveguide having two bent portions is applied, and a pair of parallel portions is provided. At least one
While two coaxial dielectric resonators are respectively arranged,
A coaxial dielectric filter in which no coaxial dielectric resonator is arranged in one linear portion connecting the parallel portions, that is, a pair of square coaxial dielectric resonators is provided on both sides of the two bent portions with the two bent portions interposed therebetween. The present invention relates to an invention that specifies the configuration of a coaxial dielectric filter disposed in a cutoff waveguide.

That is, the invention according to claim 5 is based on the premise that the coaxial dielectric filter according to the invention according to claim 1 is provided,
The blocking waveguide is constituted by a substantially U-shaped waveguide composed of a pair of parallel portions and one linear portion connecting these, and each parallel portion in the substantially U-shaped waveguide has at least one A coaxial dielectric resonator is disposed, and a first angular coaxial dielectric resonator is disposed in one of the parallel portions and adjacent to a first bent portion formed by the one parallel portion and the straight portion. A straight line of the second angular coaxial dielectric resonator which is disposed at the straight portion side end of the vessel and is adjacent to the second bent portion formed at the other parallel portion and formed by the other parallel portion and the straight portion. A coupling reinforcing member, which is made of a low-loss dielectric material and enhances electrical coupling between the first square-side coaxial dielectric resonator and the second square-side coaxial dielectric resonator, is disposed at the side end. And the coupling reinforcing member protrudes outward from the substantially disk-shaped flange portion and the center thereof to form a coaxial dielectric member on each corner side. A pair of first coupling reinforcing members provided at a central portion of the convex portion and the flange portion fitted into the inner conductor of the resonator and including a through hole penetrating the flange portion and the convex portion, and both ends of each of the first coupling reinforcing members And a rod-shaped second coupling reinforcing member fitted into the through hole of the coupling reinforcing member.

In the coaxial dielectric filter according to the fifth aspect of the present invention, similarly to the third aspect of the present invention, the cut-off waveguide has a pair of parallel portions and one straight line connecting them. Since it is composed of a substantially U-shaped waveguide consisting of a part, the arrangement space can be significantly reduced,
Since the coaxial dielectric resonators arranged in a pair of parallel parts have a positional relationship parallel to each other, an input antenna is arranged on one coaxial dielectric resonator side and the other coaxial dielectric resonator is disposed. By arranging the output side antenna on the side of the device, the input side and the output side can be arranged on the same side, so that the degree of freedom in circuit design in the package in which this coaxial dielectric filter is mounted is greatly improved. It becomes possible.

In the fifth aspect of the present invention, the same structure as the first reinforcing member according to the fourth aspect of the invention can be used as the first coupling reinforcing member. As the two-bond reinforcing member, a substance having a small loss at high frequency, for example, a rod-shaped body formed of a fluorine-based resin represented by polytetrafluoroethylene,
Alternatively, a metal rod of gold-plated copper or the like (however, a gold-plated metal rod coated with a synthetic resin film so as to prevent the conductor from being exposed from the viewpoint of preventing a short circuit in the cutoff waveguide) and the like can be mentioned.

[0034]

Embodiments of the present invention will be described below in detail with reference to the drawings.

This coaxial dielectric filter is shown in FIG.
As shown in FIG. 1, a cut-off waveguide 1 having one bent portion 10
And two coaxial dielectric resonators (1/1) which are coaxially arranged at a distance in the blocking waveguides 1 on both sides of the bent portion 10 and whose both ends are electrically open. 2
Wavelength type resonators) 21 and 22, an input-side connector 31 fixed to the input side of the cutoff waveguide 1, and a coaxial dielectric whose one end is supported by the input-side connector 31 and arranged on the input side. A rod-shaped input-side antenna 32 having the other end inserted into the input-side inner conductor of the resonator 21 via a sleeve 51 made of polytetrafluoroethylene, and an output-side connector fixed to the output side of the cutoff waveguide 1 41, the other end of which is inserted through a sleeve 52 made of polytetrafluoroethylene into the output-side inner conductor of the coaxial dielectric resonator 22 whose one end is supported by the output-side connector 41 and disposed on the output side. The main part is constituted by a rod-shaped output antenna 42, and both ends of the input antenna 32 and the output antenna 42 are connected to the input connector 31, the sleeve 51 and the output. It has a structure supported by a connector 41 and a sleeve 52 in a double-supported manner, and further has a coaxial type dielectric disposed in an output side inner conductor and an output side of a coaxial type dielectric resonator 21 disposed on an input side. In the input-side inner conductor of the body resonator 22 (that is, in the adjacent-side inner conductor of a pair of square-side coaxial dielectric resonators adjacent to each other with the bent portion 10 interposed therebetween), the same structure as the sleeves 51 and 52 is used. The coupling reinforcing members 61 and 62 made of tetrafluoroethylene are fitted.

As shown in FIG. 1B, the cut-off waveguide 1 has a metal case 11 having a substantially U-shaped cross section and a substantially L-shaped flat surface obtained by bending a plate-shaped duralumin. And a substantially L-shaped duralumin metal cover (not shown) for closing the upper open portion of the metal case 11. The coaxial dielectric resonators 21 and 22 are arranged as shown in FIG. As shown in the drawing, a cylindrical main body formed of barium or titanium-based oxide ceramics and having a rectangular external cross section and a circular cylindrical cross section, and a thick film provided on the inner and outer peripheral surfaces of the cylindrical main body The main part is composed of a conductive layer made of silver paste (the conductive layer provided on the inner peripheral surface is referred to as an inner conductor, and the conductive layer provided on the outer peripheral surface is referred to as an outer conductor). It is open.

Further, the sleeves 51 and 52 are arranged as shown in FIG.
(A) As shown, substantially disk-shaped flange portions 55 and 56, and convex portions 57 and 58 having a circular cross section protruding outward from the center.
And antenna introduction holes 53, 54 provided at the center of the flanges 55, 56 and penetrating through the flanges 55, 56 and the convex portions 57, 58, and the main part thereof is formed. The convex portions 57 and 58 are fixedly arranged to be fitted into the antenna insertion portions in the input-side inner conductor and the output-side inner conductor of the dielectric resonators (1/2 wavelength resonators) 21 and 22, respectively. The other ends of the input-side antenna 32 and the output-side antenna 42 are respectively inserted into the inner conductors of the coaxial dielectric resonators (1/2 wavelength resonators) 21 and 22 via these sleeves 51 and 52, respectively. As described above, both ends of the antennas 32 and 42 are inserted and supported by the input side connector 31 and the sleeve 51 and the output side connector 41 and the sleeve 52 in a double-supporting manner.

The coupling reinforcing members 61, 62 have the same structure as the sleeves 51, 52 as described above, but may have a structure without the antenna introduction holes 53, 54. In addition, these coupling reinforcing members 6
Numerals 1 and 62 are members incorporated for adjusting the strength of electrical coupling between the coaxial dielectric resonators 21 and 22 adjacent to each other with the bent portion 10 interposed therebetween. Naturally, a configuration in which only one of 61 and 62 is incorporated may be used.

In this coaxial dielectric filter, an input signal is passed through an input antenna 32 to an inner conductor of a coaxial dielectric resonator (1/2 wavelength resonator) 21 disposed on the input side. It is capacitively coupled and excites the coaxial dielectric resonator 21. Next, the excited resonance energy of the coaxial dielectric resonator 21 is transmitted from the open end on the opposite side to the coaxial dielectric resonator (１ ／ wavelength resonator) 22 disposed on the output side, and Are output via the output-side antenna 42.

As described above, in the coaxial dielectric filter according to the embodiment, the adjacent end between the coaxial dielectric resonators 21 and 22 sandwiching the bent portion 10 is made of polytetrafluoroethylene. The coupling reinforcing member 61,
62, the angle of the bent portion 10 in the blocking waveguide 1 is set to be as small as approximately 90 degrees, and due to this angle, the coaxial dielectric resonator adjacent to the bent portion 10 is sandwiched therebetween. Even if the electrical coupling between 21 and 22 weakens,
The weakened portion is compensated for by the coupling reinforcing members 61 and 62 to adjust the strength of the electrical coupling between the coaxial dielectric resonators 21 and 22, so that the coaxial dielectric resonator disposed on the input side is adjusted. A coaxial dielectric resonator 22 and an output antenna 42 disposed on the output side between the input antenna 21 and the input antenna 32.
And two coaxial dielectric resonators 21, 22
The three electrical coupling degrees can be balanced, and as a result, the coaxial dielectric filter can have desired characteristics.

Further, in this coaxial dielectric filter, the cut-off waveguide 1 having the bent portion 10 is applied, so that the length of the filter can be reduced. When integrated and mounted on a device, by arranging components such as electronic circuits in the space on the inner peripheral side of the bent portion 10 in the cutoff waveguide 1, dead space is eliminated and the size can be significantly reduced. .

The coaxial dielectric filter shown in FIGS. 2A and 2B is a modification of the coaxial dielectric filter according to the embodiment shown in FIG. 1B. .

That is, in the coaxial dielectric filter shown in FIG. 2A, the antennas 32, 4 and 4 are provided in support holes (not shown) provided on the input side and the output side wall of the metal case 11.
The antenna has a structure in which the antenna 2 is supported by fitting the ends of the antenna 2 and the ends of the antennas 32 and 42 exposed from the support holes of the metal case 11 to a circuit board on which the coaxial dielectric filter is incorporated. Is adapted to be connected to a connection portion as appropriate.

In the coaxial dielectric filter shown in FIG. 2B, the input side and the output side wall of the metal case 11 are opened, and each coaxial dielectric resonator is opened from the open side through the sleeves 51 and 52. The antennas 32 and 42 supported by the devices 21 and 22 have end portions protruding outward. The ends of the antennas 32 and 42 are connected to a circuit board on which the coaxial dielectric filter is incorporated. Is adapted to be connected to a connection portion as appropriate.

In the coaxial dielectric filter according to the embodiment shown in FIG. 1B and FIGS. 2A and 2B, cut-off waveguides on both sides of the bent portion 10 are provided. Tube 1
The structure is such that one coaxial dielectric resonator 21 and 22 are arranged in each of them. However, two or more coaxial dielectric resonators can be respectively arranged depending on the characteristics required for the filter. It is. In this case, the bent portion 10
A pair of coaxial dielectric resonators adjacent to each other are located near the corners (that is, the bent portions) in the cutoff waveguide 1 (the cutoff waveguides 1 on both sides of the bent portion 10). In the case where one coaxial dielectric resonator is arranged in each of them, each coaxial dielectric resonator is located near the corner side in the cutoff waveguide 1). In the specification, the pair of coaxial dielectric resonators is referred to as a square coaxial dielectric resonator, and at least one of the adjacent end portions of the pair of square coaxial dielectric resonators. It is a requirement that a connection reinforcing member be provided in the vehicle.

In this case, as the number of coaxial dielectric resonators arranged in the cutoff waveguide 1 increases, the distance between the antenna and the coaxial dielectric resonator and between the adjacent coaxial dielectric resonators increases. The number of objects for balancing the degree of electrical coupling between devices and the like also increases.

Therefore, the coupling reinforcing member is also provided at each adjacent end between coaxial dielectric resonators arranged linearly in the blocking waveguide 1 extending on both sides with the bent portion 10 interposed therebetween. By doing so (claim 2), the balance adjustment of the degree of electrical coupling can be simplified.

Next, as the coaxial dielectric filter shown in FIGS. 3A to 3C, a substantially U-shaped waveguide having two bent portions is used. And one coaxial dielectric resonator is arranged in each of the parallel portions and one linear portion connecting these parallel portions.

That is, this coaxial dielectric filter is:
It is composed of a pair of parallel portions 101 and 102 and one linear portion 103 connecting them, and the first bent portion 104 formed by one parallel portion 101 and the linear portion 103 and the other parallel portion 102 and the linear portion 103 and the second bent portion 10
5, a cut-off waveguide 1 having a substantially U-shape in plan view having two bent portions, and one coaxial waveguide disposed at the input side parallel portion 101 of the cut-off waveguide 1 and having both ends electrically open. -Shaped dielectric resonator (１ ／ wavelength resonator) 21 and one coaxial dielectric resonator which is arranged in the output side parallel portion 102 of the cutoff waveguide 1 and whose both ends are electrically open. (１ ／ wavelength resonator) 22 and one coaxial dielectric resonator (１ ／ wavelength resonator) disposed on the linear portion 103 of the cutoff waveguide 1 and having both ends electrically open. vessel)
23, an input connector 31 fixed to the input side of the cutoff waveguide 1, and a coaxial dielectric resonator 21 supported at one end by the input connector 31 and disposed on the input side.
A rod-shaped input-side antenna 32 having the other end inserted into the input-side inner conductor via a sleeve 51 made of polytetrafluoroethylene; an output-side connector 41 fixed to the output side of the blocking waveguide 1; A rod-shaped output having one end supported by the output-side connector 41 and the other end inserted through a sleeve 52 made of polytetrafluoroethylene into an output-side inner conductor of a coaxial dielectric resonator 22 disposed on the output side. The main part is constituted by the side antenna 42, and both ends of the input side antenna 32 and the output side antenna 42 are supported by the input side connector 31 and the sleeve 51 and the output side connector 41 and the sleeve 52 in a double-supporting manner. Further, the coaxial dielectric resonator 21 disposed on the input side parallel portion 101 and the coaxial dielectric resonator disposed on the linear portion 103 Between the coaxial dielectric resonators 22 disposed in the output side parallel portion 102 and the coaxial dielectric resonators 23 disposed in the Polytetrafluoroethylene coupling reinforcing members 61, 62, 63, 64 having the same structure as the sleeves 51, 52 are fitted in the inner conductor at the adjacent end.

Further, the cut-off waveguide 1 is shown in FIGS.
(C) As shown in FIG.
01, 102 and a linear portion 103), an aluminum metal case 11 provided with an aluminum metal cover 12 for closing an upper opening of the metal case 11, and The coaxial dielectric resonators 21, 22, and 23 arranged in the accommodating section 10 are shown in FIG.
As shown in (A), a cylindrical main body made of barium or titanium-based oxide ceramic and having a quadrangular external cross section and a circular cylindrical cross section is provided on the inner and outer peripheral surfaces of the cylindrical main body. The main part is constituted by the conductive layer made of the thick film silver paste, and both ends are electrically opened.

In this coaxial dielectric filter, a coupling reinforcing member made of polytetrafluoroethylene is provided at the adjacent end between the coaxial dielectric resonators 21 and 23 sandwiching the first bent portion 104 therebetween. 61, 63 are fitted, and coupling reinforcing members 64, 62 made of polytetrafluoroethylene are provided at the adjacent side ends between the coaxial dielectric resonators 23, 22 adjacent to each other across the second bent portion 105.
Is inserted, the angle between the first bent portion 104 and the second bent portion 105 in the blocking waveguide 1 is set to be as small as approximately 90 degrees, and due to this angle, the first bent portion 104 is formed. Coaxial dielectric resonator 2 adjacent to each other
Even if the electrical coupling between the coaxial dielectric resonators 23 and 22 adjacent to each other between the first and the second and the second bent portion 105 is weakened, the weakened electrical coupling is applied to the coupling reinforcing members 61 and 62,
63, 64 compensate for the coaxial dielectric resonators 21, 23,
In addition, since the strength of electrical coupling between the coaxial dielectric resonators 23 and 22 is adjusted, between the coaxial dielectric resonator 21 disposed on the input side and the input antenna 32 and on the output side. Between the disposed coaxial dielectric resonator 22 and the output-side antenna 42, and the three coaxial dielectric resonators 21,
It is possible to balance the four degrees of electrical coupling between 22 and 23, and as a result, it is possible to provide the coaxial dielectric filter with desired characteristics.

Further, the cutoff waveguide 1 is a pair of parallel portions 1
Since it is composed of a substantially U-shaped waveguide composed of a pair of parallel portions 1 and 102 and a straight portion 103 connecting them, the arrangement space can be greatly reduced.
01, 102, each coaxial dielectric resonator 21,
22 have a parallel positional relationship with each other, and the input side and the output side are arranged on the same side, so that the degree of freedom in circuit design in a package on which the coaxial dielectric filter is mounted can be greatly improved. .

Next, as the coaxial dielectric filter shown in FIGS. 4A to 4C, a substantially U-shaped waveguide having two bent portions is used. Have a structure in which one coaxial dielectric resonator is disposed in each of the parallel portions.

That is, this coaxial dielectric filter is:
It is composed of a pair of parallel portions 101 and 102 and one linear portion 103 connecting them, and the first bent portion 104 formed by one parallel portion 101 and the linear portion 103 and the other parallel portion 102 and the linear portion 103 and the second bent portion 10
5, a cut-off waveguide 1 having a substantially U-shape in plan view having two bent portions, and one coaxial waveguide disposed at the input side parallel portion 101 of the cut-off waveguide 1 and having both ends electrically open. -Shaped dielectric resonator (１ ／ wavelength resonator) 21 and one coaxial dielectric resonator which is arranged in the output side parallel portion 102 of the cutoff waveguide 1 and whose both ends are electrically open. (１ ／ wavelength resonator) 22, an input connector 31 fixed to the input side of the cutoff waveguide 1, and a coaxial type one end of which is supported by the input connector 31 and arranged on the input side. A rod-shaped input-side antenna 32 having the other end inserted into the input-side inner conductor of the dielectric resonator 21 via a sleeve 51 made of polytetrafluoroethylene, and an output fixed to the output side of the cutoff waveguide 1 Side connector 41 and this output side connector 41 A rod-shaped output-side antenna 42 having one end supported and the other end inserted through a sleeve 52 made of polytetrafluoroethylene into an output-side inner conductor of the coaxial dielectric resonator 22 disposed on the output side. A main part is configured, and both ends of the input antenna 32 and the output antenna 42 are supported by the input connector 31 and the sleeve 51 and the output connector 41 and the sleeve 52 in a double-supporting manner. Further, the sleeves 51 and 52 are provided in the conductors at the adjacent end portions between a pair of coaxial dielectric resonators 21 and 22 adjacent to each other with the two first bent portions 104 and the second bent portion 105 interposed therebetween. The same structure (that is, a substantially disk-shaped flange portion, a convex portion projecting outward from the center thereof and fitted into the inner conductor of the coaxial dielectric resonator, and a flange portion provided at the center of the flange portion, (Comprising a through-hole penetrating the shaped part), the first coupling reinforcing members 61 and 62 made of polytetrafluoroethylene are fitted, one end of the first coupling reinforcing member 61 is fitted into the through-hole, and the other end is the first coupling reinforcing member. A rod-shaped second coupling reinforcing member 60 fitted in the through hole of the reinforcing member 62 is disposed on the linear portion 103 of the blocking waveguide 1, and these first coupling reinforcing members 61 and 62 and the second coupling reinforcing member 60 are provided. Thus, the electrical coupling between the coaxial dielectric resonators 21 and 22 is reinforced.

The cut-off waveguide 1 and the coaxial dielectric resonator 2
1 and 22 are the same as those shown in FIGS. 3 (A) to 3 (C).

In this coaxial dielectric filter, the adjacent end portions between a pair of coaxial dielectric resonators 21 and 22 adjacent to each other with the two first bent portions 104 and the second bent portion 105 interposed therebetween. Is provided with a coupling reinforcing member composed of the first coupling reinforcing members 61 and 62 and the second coupling reinforcing member 60, so that the first bent portion 104 and the second bent portion of the blocking waveguide 1 are provided. The angle of the portion 105 is set to be as small as approximately 90 degrees, and due to this angle, a pair of coaxial dielectric resonators 21 and 22 are arranged in parallel, and the electric energy between these coaxial dielectric resonators 21 and 22 is set. Even if the optical coupling is weakened, the weakened portion is compensated for by the coupling reinforcing member composed of the first coupling reinforcing members 61 and 62 and the second coupling reinforcing member 60, and the electrical coupling between the coaxial dielectric resonators 21 and 22 is made. Is adjusted because the strength of During the coaxial dielectric resonator 21 disposed on the side and between the input-side antenna 32, a coaxial dielectric resonator 22 disposed on the output side and the output-side antenna 42,
In addition, it is possible to balance three degrees of electrical coupling between the two coaxial dielectric resonators 21 and 22, so that the coaxial dielectric filter can have desired characteristics. Become.

Further, as in the case of the coaxial dielectric filter shown in FIGS. 3A to 3C, the cutoff waveguide 1 has a pair of parallel portions 101 and 102 and one linear portion connecting them. 1
03, the arrangement space can be greatly reduced, and the coaxial dielectric resonators 21 and 22 disposed on the pair of parallel portions 101 and 102 are mutually connected. Since the input side and the output side are arranged on the same side in a parallel positional relationship, it is possible to greatly improve the degree of freedom in circuit design in a package on which the coaxial dielectric filter is mounted.

[0058]

Embodiments of the present invention will be specifically described below.

First, a coaxial dielectric filter shown in FIGS. 4A to 4C was manufactured.

In this coaxial dielectric filter, a pair of coaxial dielectric resonators (１ ／ wavelength resonator) 21,
Reference numeral 22 denotes a cylindrical main body made of barium or titanium-based oxide ceramics (having a relative dielectric constant of 37) and having a quadrangular outer cross section and a circular cross section (2.4 mm in diameter) and a cylindrical main body. And a conductive layer made of a thick silver paste provided on the inner peripheral surface and the outer peripheral surface of the conductive layer, the main part of which is constituted. The length dimensions of the coaxial dielectric resonators (1/2 wavelength resonators) 21 and 22 are 1
It is set to 0.385 mm. The lengths of the antenna portions of the input-side antenna 32 and the output-side antenna 42 are each set to 11.15 mm. Also,
The first coupling reinforcing members 61 and 62 are
2 (ie, a substantially disk-shaped flange portion, a convex portion protruding outward from the center thereof and fitted into the inner conductor of the coaxial dielectric resonator), and a flange portion provided at the center of the flange portion. And a through-hole penetrating through the convex portion).
Numeral 0 is composed of a metal rod made of copper and a PVC coating covering this surface.

The input connector 31 and the input antenna 32 and the output connector 41 and the output antenna 42
The coaxial dielectric resonator (1) is provided at a predetermined position in the substantially U-shaped housing portion 10 of the metal case 11 in which the
/ 2 wavelength resonators) 21 and 22, and the first coupling reinforcing members 61 and 62 and the second coupling reinforcing member 60 are provided at adjacent end portions between the coaxial dielectric resonators 21 and 22. Is provided, and adjustment is performed by measuring the characteristic value of the filter with a network analyzer to obtain the above-described coaxial dielectric filter. With respect to the loss, good results were obtained with a Q value of 631 and an insertion loss of 12.161 dB.

[0062]

According to the coaxial dielectric filter according to the first and fourth aspects of the present invention, at least one of the adjacent end portions of the pair of square coaxial dielectric resonators adjacent to each other with the bent portion interposed therebetween. Is provided with a coupling reinforcing member made of a low-loss dielectric material and strengthening the electrical coupling between the coaxial dielectric resonators on the conformal side. Even if the electrical coupling between a pair of adjacent angular coaxial dielectric resonators sandwiching the bent portion is weakened due to the set angle, the weakened portion is used as the coupling reinforcing member. To compensate for the strength of the electrical coupling between the coaxial dielectric resonators on the side, so that the required degree of electrical coupling can be balanced and a coaxial dielectric filter having desired characteristics can be obtained. Has an effect.

According to the coaxial dielectric filter according to the second and fourth aspects of the present invention, two or more coaxial dielectric resonators are respectively disposed in each of the cut-off waveguides on both sides of the bent portion. In each of the cut-off waveguides, the adjacent coaxial dielectric resonator and the adjacent coaxial dielectric resonator and the adjacent coaxial dielectric resonators have adjacent ends, and the adjacent coaxial dielectric resonators other than the above-described coaxial dielectric resonator. A coupling reinforcing member made of a low-loss dielectric material and enhancing electric coupling between adjacent coaxial dielectric resonators is provided at at least one of the adjacent ends between the other coaxial dielectric resonators. With this arrangement, it is possible to easily adjust the balance of the required degree of electrical coupling despite the fact that two or more coaxial dielectric resonators are incorporated in each cut-off waveguide. Has an effect.

Next, according to the coaxial dielectric filter according to the third and fifth aspects of the present invention, the cut-off waveguide has a substantially U-shape comprising a pair of parallel portions and a single linear portion connecting the parallel portions. The arrangement space can be greatly reduced by being constituted by a waveguide, and the coaxial dielectric resonators arranged in a pair of parallel parts have a positional relationship parallel to each other. By arranging the input side antenna on the dielectric resonator side and arranging the output side antenna on the other coaxial dielectric resonator side, the input side and the output side can be arranged on the same side. This has the effect of greatly improving the degree of freedom in circuit design in the package on which the coaxial dielectric filter is mounted.

[Brief description of the drawings]

FIG. 1A is a schematic perspective view of a sleeve incorporated in a coaxial dielectric filter according to an embodiment, and FIG. 1B.
FIG. 3 is a plan view of the coaxial dielectric filter according to the embodiment in which a bent portion is removed, with the lid removed.

FIGS. 2A and 2B are plan views of a coaxial dielectric filter according to a modified example of one embodiment, in which a bent portion is removed.

FIG. 3A is a plan view of the coaxial dielectric filter having two bent portions according to the embodiment with the lid removed, and FIG. 3B is a plan view of the coaxial dielectric filter provided with the lid. FIG. 3C is a side view of the coaxial dielectric filter provided with a lid.

FIG. 4 (A) is a plan view of a coaxial dielectric filter according to a modification of the embodiment having two bent portions with the lid removed, and FIG. 4 (B) is a coaxial dielectric filter provided with a lid; FIG. 4C is a rear view of the filter, and FIG. 4C is a side view of the coaxial dielectric filter provided with a lid.

FIG. 5 is an equivalent circuit diagram of a typical dielectric filter using a coaxial dielectric resonator.

FIG. 6 is a plan view of a conventional coaxial dielectric filter using a capacitor, in which the lid is removed.

7A is a plan view of a conventional coaxial dielectric filter without using a capacitor or the like in which a lid is removed, and FIG. 7B is a plan view of a conventional coaxial dielectric filter without using a capacitor or the like; FIG.

FIG. 8 is a plan view of the coaxial dielectric filter having a bent portion with the lid removed.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 cut-off waveguide 10 bent portion 21 coaxial dielectric resonator 22 coaxial dielectric resonator 31 input connector 41 output connector 32 input antenna 42 output antenna 51 sleeve 52 sleeve 61 coupling reinforcing member 62 coupling reinforcing member

Claims (5)

[Claims] 1. A cut-off waveguide having at least one bent portion, and coaxially disposed at a distance in a cut-off waveguide on both sides of the cut-off portion with the cut-off waveguide interposed therebetween. At least two coaxial dielectric resonators each having an outer conductor and an inner conductor provided on a peripheral surface, and a rod-shaped input having one end inserted into the input-side inner conductor of the coaxial dielectric resonator disposed on the input side. Side antenna, and a rod-shaped output-side antenna having one end inserted into the output-side inner conductor of the coaxial dielectric resonator disposed on the output side, the coaxial dielectric filter comprising: At least one of the adjacent end portions of the pair of adjacent angular coaxial dielectric resonators is formed of a low-loss dielectric material and is coupled to enhance electrical coupling between the equiangular coaxial dielectric resonators. Characterized in that a reinforcing member is provided Coaxial dielectric filter. 2. Two or more coaxial dielectric resonators are respectively disposed in each of the cut-off waveguides on both sides of the bent portion, and in each of the cut-off waveguides, a square coaxial-type dielectric resonator is provided. And at least each of the adjacent side ends of the other coaxial dielectric resonators adjacent to and between the coaxial dielectric resonators other than the corner side coaxial dielectric resonator and the other adjacent coaxial dielectric resonators. 2. The coaxial dielectric according to claim 1, further comprising a coupling reinforcing member made of a low-loss dielectric material and enhancing electric coupling between adjacent coaxial dielectric resonators. Body filter. 3. The waveguide according to claim 1, wherein said cut-off waveguide comprises a substantially U-shaped waveguide comprising a pair of parallel portions and one linear portion connecting the pair of parallel portions. And one linear coaxial dielectric resonator is disposed in the linear portion, and each coaxial dielectric resonator disposed in one parallel portion and each coaxial dielectric resonator disposed in the linear portion. A low-loss dielectric material is provided at the adjacent end and at each adjacent end between the coaxial dielectric resonator disposed in the straight portion and the coaxial dielectric resonator disposed in the other parallel portion. 2. The coaxial dielectric filter according to claim 1, further comprising a coupling reinforcing member for enhancing electrical coupling between adjacent coaxial dielectric resonators. 4. The method according to claim 1, wherein the coupling reinforcing member comprises a substantially disk-shaped flange portion and a convex portion projecting outward from the center thereof and fitted into the inner conductor of the coaxial dielectric resonator. The coaxial dielectric filter according to claim 1, 2 or 3, wherein: 5. The waveguide according to claim 1, wherein said cut-off waveguide comprises a substantially U-shaped waveguide comprising a pair of parallel portions and a straight portion connecting them. , At least one coaxial dielectric resonator is respectively disposed, and is disposed on one parallel portion and adjacent to a first bent portion formed by the one parallel portion and the straight portion. A second side coaxial dielectric disposed adjacent to the straight portion of the coaxial dielectric resonator and disposed at the other parallel portion and adjacent to the second bent portion formed by the other parallel portion and the straight portion; Strengthening the electrical coupling between the first coaxial dielectric resonator and the second coaxial dielectric resonator made of a low-loss dielectric material at the end of the linear resonator on the side of the linear portion. A member is arranged, and
The coupling reinforcing member is provided at a central portion of the substantially disk-shaped flange portion, the convex portion projecting outward from the center thereof, and fitted into the inner conductor of each of the angular coaxial dielectric resonators, and the flange portion; It is composed of a pair of first coupling reinforcing members formed of a through hole penetrating the flange and the convex portion, and a rod-shaped second coupling reinforcing member whose both end sides are fitted into the through holes of each first coupling reinforcing member. The coaxial dielectric filter according to claim 1, wherein: