JPH09294002A - Dielectric filter - Google Patents

Abstract

(57) Abstract: With a conventional dielectric filter, it is difficult to confirm the connection between the base substrate and the island conductor / outer conductor of the dielectric resonator, and the reliability of soldering is low. Further, if the cross-sectional shape of the coaxial dielectric resonator is increased in order to reduce the loss, the dielectric filter becomes large. SOLUTION: A plurality of coaxial dielectric resonators 4 each having an island-shaped conductor 10 insulated from an outer conductor 9 on a side surface of a dielectric substrate 6 are formed on a base substrate 2 on which a predetermined conductor pattern 3 is formed.
The island-shaped conductors 10 and a plurality of reactance elements are formed on the exposed side surface by arranging the coaxial dielectric resonators 4 which are adjacent to each other substantially vertically to the base substrate 2 by shifting them. This is a dielectric filter 1 in which 11 and 11 are connected by a conductor pattern 3. Further, by inserting the coaxial dielectric resonator 4 into the opening 5 provided in the base substrate 2, it is possible to achieve both low loss and low profile / miniaturization.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dielectric filter using a coaxial dielectric resonator used in mobile communication devices such as mobile phones.

[0002]

2. Description of the Related Art Dielectric filters using coaxial dielectric resonators are used in mobile communication devices such as mobile phones, portable radios and car phones. The body filter is also required to be downsized.

The above-mentioned dielectric filter is usually constructed by arranging a plurality of quarter-wave type or half-wave type coaxial dielectric resonators on a substrate and connecting them by a conductor pattern, a capacitor and an inductance. ing. For example, Japanese Unexamined Patent Publication No. 5-167308 discloses a dielectric resonance including a dielectric block having a resonance hole and a conductor film forming an earth pattern formed on an inner surface of the resonance hole and a predetermined portion of the dielectric block. In a dielectric filter configured by arranging a plurality of resonators side by side and LC coupling between the plurality of dielectric resonators, a side surface of each dielectric resonator faces another adjacent dielectric resonator. There has been proposed a dielectric filter in which a capacitance pattern that forms a capacitance is formed between an inner conductor film and an inner conductor film on a side surface that is not formed, and the capacitance patterns are coupled by an inductance.

Further, in the publication, a ground pattern and a terminal pattern are formed at predetermined positions on a surface mounting base plate, and the conductor film and the capacitance pattern provided on the dielectric resonator with the above capacitance pattern are respectively attached to the base plate. There is disclosed a dielectric filter in which a plurality of dielectric resonators are provided side by side on a base plate so as to be in surface contact with the ground pattern and the terminal pattern provided above, and the terminal patterns are connected by an inductance. According to this dielectric filter, the capacitance between the island-shaped conductor and the conductor film on the inner surface is used as a series resonance capacitance, and the resonance units are coupled by an LC π-type phase shift circuit to form a band elimination filter. ing.

In this dielectric filter, the dielectric resonator is mounted in such a manner that its island-shaped conductor is in contact with the base plate coated with the solder paste, and then reflow soldering is performed.

According to such a dielectric filter,
External grounding capacitance parts, etc., which were indispensable in the past, are no longer required, and the capacitance can be changed by adjusting the shape and dimensions of the capacitance pattern to obtain the desired filter characteristics. However, the assembly (mounting) work is simplified and the cost is reduced.

[0007]

However, in the dielectric filter having the above-mentioned structure, the island-shaped conductor formed on the side surface of the dielectric resonator faces and abuts against the base plate, so that the island-shaped conductor is formed. There is a problem that it is difficult to confirm whether or not the conductor and the base plate are reliably soldered, and the reliability of the soldering is low.

Further, since the dielectric resonator is mounted on the base plate, if the cross-sectional shape of the dielectric resonator is increased in order to reduce the loss of the filter, the dielectric filter becomes larger. There were also points.

The present invention has been completed as a result of intensive research conducted by the present inventor in order to solve the above problems, and an object thereof is to provide a dielectric filter using a coaxial dielectric resonator on a base substrate. It is an object of the present invention to provide a highly reliable dielectric filter which can reliably and easily confirm the connection of the coaxial dielectric resonator to the wiring pattern of (3) with solder or the like.

Further, an object of the present invention is to provide a dielectric filter which can be reduced in height and size even when the cross-sectional shape of the dielectric resonator is increased in order to reduce the loss of the filter. Especially.

[0011]

In a dielectric filter according to a first aspect of the present invention, a base substrate having a predetermined conductor pattern formed on a surface or an inner layer penetrates two opposing side surfaces of a dielectric substrate. A plurality of coaxial dielectric resonators having an inner conductor in the through hole, an outer conductor on a side surface parallel to the through hole and an island conductor insulated from the outer conductor, and a plurality of reactance elements are mounted. In addition, in the dielectric filter formed by connecting each of them with the conductor pattern, the island-shaped conductor is substantially perpendicular to the base substrate, and the outer side surface or the adjacent coaxial dielectric resonators of the adjacent coaxial dielectric resonators. It is characterized in that the body resonator is formed on the exposed side surface by arranging it so as to be displaced in the direction of the through hole.

In the dielectric filter according to claim 2 of the present invention, in the above structure, at least a part of the island-shaped conductor is provided in the opening provided in the base substrate for the coaxial dielectric resonator. It is characterized in that it is fitted so as to be exposed on the upper surface of the base substrate.

According to the dielectric filter of the present invention, island-shaped conductors are provided on the side surfaces of the coaxial dielectric resonator, and the island-shaped conductors are arranged substantially perpendicular to the base substrate, and at least a part of them is formed. Since it is exposed on the base substrate and connected to the conductor pattern, the connection between the island conductor of the coaxial dielectric resonator mounted on the base substrate and the conductor pattern of the base substrate can be secured by soldering, etc. The dielectric filter can be performed and its confirmation can be easily performed, and the dielectric filter has high reliability.

According to the dielectric filter of the present invention,
By arranging the adjacent coaxial dielectric resonators on the base substrate in the direction of the through hole to expose the island-shaped conductors on the side surfaces, these island-shaped conductors should be provided at the end portions of the side surfaces of the dielectric substrate. For example, a plurality of coaxial dielectric resonators can be mounted in close proximity to each other with a minimum mounting area while being surely connected to the conductor pattern, so that the reliability is high and the size can be reduced.

Further, according to the dielectric filter of the second aspect of the present invention, the coaxial dielectric resonator is exposed in the opening provided in the base substrate, and at least a part of the island-shaped conductor is exposed on the upper surface of the base substrate. By thus fitting, even if the cross-sectional shape of the dielectric resonator is increased for the purpose of reducing the loss of the filter, the dielectric filter can be made lower in height and smaller in size than before.

Furthermore, since the coaxial dielectric resonator is fitted in the base substrate, the insertion loss of the filter (input signal to the filter, which has been conventionally caused by reducing the cross section of the coaxial dielectric resonator). It is possible to realize the height reduction of the dielectric filter by the amount of fitting into the base substrate without deteriorating the level difference from the output signal that has passed through the filter.

As described above, according to the present invention, in the dielectric filter using the coaxial dielectric resonator, the connection between the resonator and the conductor pattern can be surely and easily confirmed, and the reliability can be improved. It was possible to provide a dielectric filter that can be reduced in height and size.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below with reference to the drawings. The present invention is not limited to the following examples, and various modifications and improvements may be made without departing from the spirit of the present invention.

FIG. 1 is an external perspective view showing an embodiment of the dielectric filter of the present invention. In the dielectric filter 1 shown in the figure, 2 is a base substrate made of a dielectric or the like, and a predetermined conductor pattern 3 is formed as a wiring pattern on the surface or an inner layer thereof. The conductor pattern 3 is also extended to the side surface of the base substrate 2 at a desired portion, and is also used as a mounting terminal electrode when mounting on an external circuit board. Reference numeral 4 denotes a coaxial dielectric resonator. As shown by a dotted line in the figure, a part of the coaxial dielectric resonator is fitted into an opening 5 provided in the base substrate 2 in the present embodiment. The coaxial dielectric resonator 4 may be placed on the base substrate 2 without providing 5, or the coaxial dielectric resonator 4 may be penetrated by providing an opening penetrating the base substrate 2.

FIG. 2 also shows an external perspective view of the coaxial dielectric resonator 4. As shown in FIGS. 1 and 2, in the coaxial dielectric resonator 4 of the present invention, a dielectric substrate 6 made of barium titanate or the like is formed with a through hole 7 penetrating two opposite side surfaces thereof. The inner conductor 8 is provided on the inner surface of the through hole 7, and the outer conductor 9 and the island-shaped conductor 10 insulated from the outer conductor 9 are provided on the side surface parallel to the through hole 7. It is configured to have a predetermined capacity between. Further, a short-circuit conductor that connects the inner conductor 8 and the outer conductor 9 is formed on the opposite side surface (the side not shown) of the through hole 7 when the coaxial dielectric resonator 4 is a quarter wavelength type. In the case of the 1/2 wavelength type, such a conductor is not formed and the dielectric substrate 6 is exposed.

A plurality of such coaxial dielectric resonators 4,
The adjacent outer conductors 9 are brought into contact with each other to be connected, and in the present embodiment, the adjacent coaxial dielectric resonators 4 are arranged so as to be displaced in the direction of the through hole 7 to expose the respective island-shaped conductors 10. , Are connected to the corresponding conductor patterns 3.

Reference numeral 11 denotes a coil (inductance) as a reactance element, which is arranged so that a portion where the coaxial dielectric resonator 4 is displaced is not wasted and is connected to the conductor pattern 3 together with the coaxial dielectric resonator 4. L
The dielectric filter 1 having desired characteristics is constructed by coupling a C-type phase shift circuit of C or the like.

In the present embodiment, an example in which three coaxial dielectric resonators 4 are arranged is shown, but it may be two or four or more depending on the specifications of the dielectric filter 1. There is no end. Further, by covering with a box-shaped case as needed, invasion of electromagnetic noise from the outside and electric wave leakage to other circuits may be suppressed.

The base substrate 2 is made of a dielectric such as barium titanate or glass epoxy. The size is set according to the desired specifications of the dielectric filter, but the thickness is generally about 0.5 to 1.0 mm.

The conductor pattern 3 is made of copper (Cu) or silver (A
The conductor film of g) or the like is formed into a predetermined pattern shape by thick film printing using a mesh pattern, photoetching, or the like. When the conductor pattern 3 is formed as an inner layer on the base substrate 2, it may be formed to have a predetermined pattern shape by thick film printing or photoetching using a mesh pattern.

The material and size of the dielectric substrate 6 used for the coaxial dielectric resonator 4 may be appropriately selected according to the desired filter characteristics. For example, in the case of 900 MHz band, the attenuation pole is close in a narrow band. For the filter, use a barium titanate-based material with good high-frequency characteristics and a dielectric constant of about 90 to 100. If it is a prism, the length is 8 to 9 mm x 2 to 3 mm.
The through hole 7 having a diameter of 0.5 to 1.0 mm may be formed as a dimension of about □.

The shape of the dielectric substrate 6 is not limited to the prismatic shape shown in FIGS. 1 and 2, but may be a cylindrical shape.

The inner conductor 8 is formed over the entire inner surface of the through hole 7, and a conductor film made of copper, silver or the like may be formed to a thickness of about 5 to several tens of μm by a method such as a plating method or a thick film baking method.

The outer conductor 9 is a through hole 7 in the dielectric substrate 6.
On the side surface parallel to the inner conductor 8, the same material, forming method, thickness, etc. as the inner conductor 8 are basically formed on all four side surfaces parallel to the through hole 7.

When the short-circuit conductor is formed so as to form a quarter-wave resonator, the short-circuit conductor is formed in the same material, forming method, thickness, etc. as the inner conductor 8 and the outer conductor 9.

The island-shaped conductor 10 is provided on one of the side surfaces of the dielectric substrate 6 parallel to the through hole 7 so as to be arranged substantially perpendicular to the base substrate 2 when mounted on the base substrate 2. It is formed so as to be insulated from the conductor 9. The position, shape, size, thickness, etc. are determined so as to have a capacity for obtaining optimum characteristics of the filter. Further, the forming method is as follows. First, on the side surface of the dielectric substrate 6, a resist resin is printed on a portion where the outer conductor 9 and the island conductor 10 are not formed and dried, and then the whole is plated, and then the resist portion is peeled off. Soak in liquid and remove. Alternatively, instead of plating, a thick film paste may be applied and fired (the resist portion is burned off at this time). Alternatively, as another method, a conductor film may be applied to the entire surface by plating or thick film paste, and then a resist may be applied to a portion where the conductor is needed as it is, and an unnecessary portion of the conductor may be removed by etching. . The formation position of the island-shaped conductor 10 may be appropriately set according to the specifications for mounting the coaxial dielectric resonator 4 on the base substrate 2 as described later.

The coil (inductance) 11 may be an air core coil or a chip inductor other than the ordinary coil as shown in the figure. Further, a capacitor or strip line can be used as the reactance element.

The size and depth of the opening 5 provided in the base substrate 2 may be appropriately set according to the mounting form of the coaxial dielectric resonator 4, and the coaxial dielectric resonator 4 is just fitted as shown in the figure. In addition to the size, the size may be such that some space is provided around the coaxial dielectric resonator 4. Further, the periphery of the opening 5 is formed into a stepped shape, and the stepped portion is brought into contact with the side surface of the coaxial dielectric resonator 4 on which the island-shaped conductor 10 is formed, while the conductor pattern 3 formed on the base substrate 2 is provided inside.
May be exposed on the step surface and connected.
It should be noted that this opening 5 need not be provided especially when the coaxial dielectric resonator 4 is mounted on the upper surface of the base substrate 2.

Further, the conductor pattern 3 is formed without providing the opening 5.
Is formed on the base substrate 2, the conductor pattern 3
The coaxial dielectric resonator 4 mounted on the upper surface of the base substrate 2 and the coil 11 may be connected via a connecting conductor such as a via hole formed from the conductor pattern 3 to the upper surface of the base substrate 2.

Next, how the coaxial dielectric resonator is mounted on the base substrate will be described with reference to FIGS.

FIG. 3 (a) is a sectional view showing an example of the mounting form of the coaxial dielectric resonator on the base substrate, and FIG. 3 (b).
FIG. 4 is a side view of the coaxial dielectric resonator.

In FIG. 3A, 12 is a base substrate and 13
Is a conductor pattern formed on the surface of the base substrate 12, and 14 is a coaxial dielectric resonator. The coaxial dielectric resonator 14 has an inner conductor 17 on an inner surface of a through hole 16 formed in a prismatic dielectric substrate 15.
However, the outer conductor 18 is formed on the side surface parallel to the through hole 16, and the island-shaped conductor 19 is formed at the corner of the side contacting the base substrate 12 at the end of the side surface vertical to the base substrate 12. And 21
Is solder, and the solder 21 electrically connects the conductor pattern 13 to the island-shaped conductor 19 or the outer conductor 18. The solder 21 may be a conductive adhesive or the like, and the same applies to the following examples.

With the configuration shown in FIG. 3, the base substrate 12
It is not necessary to form an opening or the like, and the conductor pattern 13 can be reliably connected to the island-shaped conductor 19 or the outer conductor 18 by the solder 21, and can be easily confirmed.

FIG. 4A is a sectional view showing another example of the mounting form of the coaxial dielectric resonator on the base substrate.
(B) is a side view of the coaxial dielectric resonator.

In FIG. 4A, 22 is a base substrate, and 23 is
Is a conductor pattern formed on the surface of the base substrate 22, and 24 is a coaxial dielectric resonator. In this example, the coaxial dielectric resonator 24 is fitted in the opening 25 formed in the base substrate 22 up to the middle of its thickness. Coaxial dielectric resonator 24
The inner conductor 28 is formed on the inner surface of the through hole 27 formed in the prismatic dielectric substrate 26, and the outer conductor 29 is formed on the side surface parallel to the through hole 27, and the corner of the end of the side surface perpendicular to the base substrate 22 is formed. The island-shaped conductor 30 is formed in the part so that a part of the part is exposed from the opening 25 of the base substrate 22. Reference numeral 31 is solder for electrically connecting the conductor pattern 23 and the island-shaped conductor 30 or the outer conductor 29.

With the configuration shown in FIG. 4, the base substrate 22
Since the opening 25 is formed in the lower part, the height is reduced, and the solder 31 between the conductor pattern 23 and the island-shaped conductor 30 or the outer conductor 29 is formed.
The connection can be surely made and can be easily confirmed. Further, the coaxial dielectric resonator 24 can be easily positioned by fitting it into the opening 25.

FIG. 5 (a) is a sectional view showing another example of the mounting form of the coaxial dielectric resonator on the base substrate.
(B) is a side view of the coaxial dielectric resonator.

In FIG. 5A, 32 is a base substrate and 33
Is a conductor pattern formed on the surface of the base substrate 32, and 34 is a coaxial dielectric resonator. Further, in this example, the coaxial dielectric resonator 34 is fitted in the opening 35 formed so as to penetrate the base substrate 32. In the coaxial dielectric resonator 34, the inner conductor 38 is formed on the inner surface of the through hole 37 formed in the prismatic dielectric substrate 36, and the outer conductor 39 is formed on the side surface parallel to the through hole 37, and is perpendicular to the base substrate 32. Island-shaped conductors 40 are formed at the corners of the end portions of the side surface so that a part of the conductor 40 is exposed from the opening 35 of the base substrate 32. In this case, the coaxial dielectric resonator
The configuration of 34 is the same as that of the coaxial dielectric resonator 24, and the base substrate
The thickness of 32 may be smaller than the height of the dielectric substrate 36. Further, the coaxial dielectric resonator 34 may be fitted so as to penetrate the base substrate 32. 41 is a solder for electrically connecting the conductor pattern 33 and the island-shaped conductor 40 or the outer conductor 39.

In the case of the configuration shown in FIG. 5, the base substrate 32
By forming the opening portion 35 penetrating the base substrate 32 in the base, the height is further reduced as compared with the example of FIG. 4, and the connection of the conductor pattern 33 and the island conductor 40 or the outer conductor 39 by the solder 41 can be surely performed. , And can be easily confirmed. In addition, the coaxial dielectric resonator 34 is positioned by the opening 35
It can be easily carried out by inserting into.

FIG. 6A is a sectional view showing another example of the mounting form of the coaxial dielectric resonator on the base substrate.
(B) is a side view of the coaxial dielectric resonator.

In FIG. 6A, 42 is a base substrate and 43
Is a conductor pattern formed on the surface of the base substrate 42, and 44 is a coaxial dielectric resonator. In this example, the coaxial dielectric resonator 44 is fitted in the opening 45 formed in the base substrate 42 up to the middle of its thickness. Coaxial dielectric resonator 44
The inner conductor 48 is formed on the inner surface of the through hole 47 formed in the prismatic dielectric substrate 46, the outer conductor 49 is formed on the side surface parallel to the through hole 47, and the center of the end portion of the side surface vertical to the base substrate 42 is formed. The island-shaped conductor 50 is formed in the part so that a part of the part is exposed from the opening 45 of the base substrate 42. Reference numeral 51 is solder for electrically connecting the conductor pattern 43 to the island-shaped conductor 50 or the outer conductor 49.

In the case of the form shown in FIG. 6, the base substrate 42
Since the opening 25 is formed in the lower part, the height is reduced, and the solder 51 between the conductor pattern 43 and the island-shaped conductor 50 or the outer conductor 49 is formed.
The connection can be surely made and can be easily confirmed. Further, the coaxial dielectric resonator 44 can be easily positioned by fitting it into the opening 45.

FIG. 7A is a sectional view showing another example of the mounting form of the coaxial dielectric resonator on the base substrate.
(B) is a side view of the coaxial dielectric resonator.

In FIG. 7A, 52 is a base substrate and 53
Is a conductor pattern formed on the surface of the base substrate 52, and 54 is a coaxial dielectric resonator. In this example, the coaxial dielectric resonator 54 is fitted into the opening 55 having a circular cross section which is formed in the base substrate 52 up to the middle of its thickness. The coaxial dielectric resonator 54 has an inner conductor 58 formed on the inner surface of a through hole 57 formed in a cylindrical dielectric substrate 56 and an outer conductor 59 formed on a side surface parallel to the through hole 57, and is substantially perpendicular to the base substrate 52. An island-shaped conductor 60 is formed in the center of the end portion of the side surface so that a part thereof is exposed from the opening 55 of the base substrate 52. Reference numeral 61 is solder for electrically connecting the conductor pattern 53 and the island conductor 60 or the outer conductor 59.

In the case of the form shown in FIG. 7, the base substrate 52
Since the opening 25 is formed in the lower portion, the height is reduced, and the solder 61 between the conductor pattern 53 and the island-shaped conductor 60 or the outer conductor 59 is formed.
The connection can be surely made and can be easily confirmed. Further, the coaxial dielectric resonator 54 can be easily positioned by fitting it into the opening 55.
Further, when manufacturing the coaxial dielectric resonator 54, the dielectric substrate 56 can be processed and manufactured in a non-directional state.

In the above-mentioned structure of the coaxial dielectric resonator, the example in which the island-shaped conductor is formed at the end portion of the dielectric substrate is shown. However, the island-shaped conductor may be formed on the dielectric substrate according to the specifications of the dielectric filter. It may be formed in a desired portion such as the central portion.

Although the through hole is illustrated as a circle, it may be formed in a quadrangle or an ellipse.

Next, another embodiment of the dielectric filter of the present invention is shown in an external perspective view in FIG.

An equivalent circuit diagram of this dielectric filter is shown in FIG.

In the dielectric filter 62 shown in FIGS. 8 and 9, 63 is a base substrate, and 64 to 69 are coaxial dielectric resonators, and the openings 70 and 71 formed in the base substrate 63, respectively.
Has been inserted into. Each of the coaxial dielectric resonators 64 to 69 has an inner conductor 74 formed in a through hole 73 penetrating two opposing side surfaces of the dielectric substrate 72, and an outer conductor 75 formed in a side surface parallel to the through hole 73. Furthermore, the coaxial dielectric resonators 64-67 and 69 are through holes.
An island-shaped conductor 76 insulated from the outer conductor 75 is provided on a side surface parallel to 73, and has capacitances (capacitor components) C64 to C67 and C69 between the conductors and the inner conductor 74. As a result, these capacitor components C64 to C67 and C69, which are conventionally required as external capacitors, are formed inside the coaxial dielectric resonators 64 to 67 and 69.

Coaxial dielectric resonator 64 fitted in the opening 70
66 has a structure in which adjacent ones are connected to each other by an outer conductor 75 and are connected by an island-shaped conductor 76 and an air-core coil 78 having inductance components L1 to L3 by a conductor pattern 77 arranged on the base substrate 63. And constitutes a transmission filter. The air-core coil 78 is fitted in a hole 79 provided in the base substrate 63 for easy positioning.

On the other hand, the coaxial dielectric resonators 67 to 69 fitted in the openings 71 are connected to each other by the outer conductor 75 and have no electrodes provided on the side surfaces of the coaxial dielectric resonators 67 to 69. The coaxial dielectric resonators 67 and 69 are coupled by the slit 80, and the capacitance between the island-shaped conductor 76 and the inner conductor 74 is used as matching capacitances C67 and C69. The coaxial dielectric resonator 68 has slits 80 on both side surfaces in contact with the coaxial dielectric resonators 67 and 69, and does not have the island-shaped conductor 76.

Further, the capacitors C1 to C5 shown in the equivalent circuit diagram.
Are formed inside the base substrate 63 by using electrodes.

Reference numeral 81 denotes an antenna terminal, which is formed by extending the conductor pattern 77 in the concave portion provided on the side surface of the base substrate 63.
Ant corresponds to the transmission terminal Tx, 82 corresponds to the reception terminal Rx, and the other recesses correspond to the ground terminal G.

In the present embodiment as well, the base substrate 63 may be covered by the box-shaped case as described above.

As can be seen from FIG. 8, the coaxial dielectric resonator
64-67 / 69 and the conductor pattern 77 on the base substrate 63 are connected to each other such that the island-shaped conductors 76 of the coaxial dielectric resonators 64-67 / 69 are positioned substantially perpendicular to the base substrate 63 and a part thereof. Are exposed on the upper surface of the base substrate 63 and are connected to the conductor patterns 77 by solder or the like. Here, the coaxial dielectric resonator 66 is different from the coaxial dielectric resonator 65 in that the island-shaped conductor 76 and the conductor pattern 77 of the coaxial dielectric resonator 65 are used.
In order to connect to each other, they are arranged so as to be displaced in a direction parallel to the through hole 73.

The dielectric filter of the present invention having such a configuration
According to 62, it is possible to obtain the highly reliable dielectric filter 62 as one that can reliably and easily confirm the connection between each island-shaped conductor 76 and the conductor pattern 77, and also to increase the height of the dielectric filter 62. Each coaxial dielectric resonator without increasing the
The cross-sectional shape of 64-69 can be increased, and as a result, it is possible to obtain the dielectric filter 62 that achieves both low loss and low profile / miniaturization.

Further, also in this embodiment, the coaxial dielectric resonators 64 to 69 may be mounted on the base substrate 63 or may be penetrated through the base substrate 63. The island-shaped conductor 76 of each of the containers 64 to 67, 69 may be formed in the central portion of the side surface, or the dielectric substrate 72 may be formed in a cylindrical shape or the like, and the advantageous effects of the present invention can also be obtained by these.

[0064]

As described above, according to the present invention, as a dielectric filter using a coaxial dielectric resonator, an island-shaped conductor is provided on a side surface of the coaxial dielectric resonator, and the island-shaped conductor is used as a base substrate. Since they are arranged almost vertically with respect to each other and at least a part of them are connected to the conductor pattern exposed on the base substrate, the island-shaped conductor of the coaxial dielectric resonator mounted on the base substrate and the base substrate. It was possible to provide a highly reliable dielectric filter which can be surely connected to the conductor pattern by soldering or the like and can be easily confirmed.

Further, according to the present invention, the coaxial dielectric resonators adjacent to each other on the base substrate are displaced in the direction of the through holes to expose the island-shaped conductors on the side surfaces, so that the island-shaped conductors are dielectric. If it is provided at the end of the side surface of the body substrate, multiple coaxial dielectric resonators can be securely connected to the conductor pattern and can be mounted in close proximity with a minimum mounting area, which is highly reliable and compact. It was possible to provide a dielectric filter capable of achieving the above.

Further, according to the dielectric filter of the second aspect of the present invention, the coaxial dielectric resonator is exposed in the opening provided in the base substrate, and at least a part of the island-shaped conductor is exposed on the upper surface of the base substrate. By providing such a fit, it is possible to provide a dielectric filter that can be made lower in height and smaller in size than before even when the cross-sectional shape of the dielectric resonator is increased in order to reduce the loss of the filter. I was able to.

Is obtained.

Therefore, according to the present invention, even when the cross-sectional shape of the coaxial dielectric resonator is made large for the purpose of reducing the loss of the filter, a dielectric filter which can be made low in height and small in size is provided. Could be provided.

[Brief description of drawings]

FIG. 1 is an external perspective view showing an embodiment of a dielectric filter of the present invention.

FIG. 2 is an external perspective view of a coaxial dielectric resonator according to the present invention.

FIG. 3A is a sectional view showing an example of a mounting form of a coaxial dielectric resonator on a base substrate in the dielectric filter of the present invention, and FIG. 3B is a side view of the coaxial dielectric resonator. is there.

FIG. 4A is a cross-sectional view showing another example of the mounting form of the coaxial dielectric resonator on the base substrate in the dielectric filter of the present invention, and FIG. 4B is a side view of the coaxial dielectric resonator. It is a figure.

5A is a cross-sectional view showing another example of mounting form of the coaxial dielectric resonator on the base substrate in the dielectric filter of the present invention, and FIG. 5B is a side view of the coaxial dielectric resonator. It is a figure.

FIG. 6A is a sectional view showing another example of the mounting form of the coaxial dielectric resonator on the base substrate in the dielectric filter of the present invention, and FIG. 6B is a side view of the coaxial dielectric resonator. It is a figure.

7A is a cross-sectional view showing another example of the mounting form of the coaxial dielectric resonator on the base substrate in the dielectric filter of the present invention, and FIG. 7B is a side view of the coaxial dielectric resonator. It is a figure.

FIG. 8 is an external perspective view showing another embodiment of the dielectric filter of the present invention.

9 is an equivalent circuit diagram of the dielectric filter of FIG.

[Explanation of symbols]

1, 62 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Dielectric filter 2, 12, 22, 32, 42, 52, 63 ・ ・ ・ Base substrate 3, 13, 23, 33, 43 , 53, 77 ... Conductor patterns 4, 14, 24, 34, 44, 54, 64-69 ... Coaxial dielectric resonators 5, 25, 35, 45, 55, 70, 71 ... ..Openings 6, 15, 26, 36, 46, 56, 72 ... Dielectric substrate 7, 16, 27, 37, 47, 57, 73 ... Through holes 8, 17, 28 , 38, 48, 58, 74 ... Inner conductor 9, 18, 29, 39, 49, 59, 75 ... Outer conductor 10, 19, 30, 40, 50, 60, 76 ...・ ・ ・ Island conductor 11 ・ ・ ・ Coil (inductance: reactance element) 78 ・ ・ ・ Air core coil (reactance element)

Claims (2)

[Claims] 1. A base substrate having a predetermined conductor pattern formed on a surface or an inner layer, an inner conductor is provided in a through hole penetrating two opposing side surfaces of a dielectric substrate, and an outer conductor is provided on a side surface parallel to the through hole. And a plurality of coaxial dielectric resonators each having an island-shaped conductor insulated from the outer conductor, and a plurality of reactance elements mounted on the dielectric filter, each of which is connected by the conductor pattern, The island-shaped conductors are substantially perpendicular to the base substrate, and exposed by arranging the outer side surfaces of the adjacent coaxial dielectric resonators or the adjacent coaxial dielectric resonators in the direction of the through hole. A dielectric filter characterized by being formed on a side surface. 2. The coaxial dielectric resonator is fitted into an opening provided in the base substrate so that at least a part of the island-shaped conductor is exposed on the upper surface of the base substrate. The dielectric filter described.