JP3349476B2 - Dielectric resonator and dielectric filter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a triple mode dielectric resonator which can use three resonance modes with one dielectric block, and a dielectric filter using such a dielectric resonator.

[0002]

2. Description of the Related Art Hitherto, in order to realize a low-loss and small-sized filter, a dielectric filter using a dielectric resonator having a high no-load Q has been used. In particular, in a filter in which low-loss characteristics are important, the dielectric filter is configured using a TE _{01 δ-} mode dielectric resonator that minimizes the conductor loss in principle. On the other hand, to reduce the size of the dielectric filter, a dielectric resonator made of a dielectric material having a high relative permittivity and a high unloaded Q is used.

However, when a dielectric filter used for wireless communication in a microwave band, for example, is constituted by using a large number of dielectric resonators of the TE _{01 δ} mode, one resonance is required for one resonance. Resonators and a space for coupling between the resonators is required, so that a large number of resonators and the space between the resonators occupy a large volume and weight, resulting in a small and lightweight dielectric filter. Was difficult. Therefore,
Even with a band-pass filter using a relatively small dielectric resonator, there is a problem that it is unavoidable that the band-pass filter has a complicated configuration and becomes large.

Therefore, in order to fully utilize the advantage of using a dielectric resonator and to realize a band-pass filter having an extremely small size and a simple configuration, a dielectric filter using a dielectric resonator capable of multi-mode resonance is constructed. It has been proposed to. For example, Japanese Patent Laid-Open No. 7-58516, made different from each other two resonance frequencies of the resonant modes, the band pass has been proposed to reduce the size of the filter, TE ₁₀₁ therein having a double-tuned band characteristic, A degenerate coupling of two resonance modes to a TE _{11 δ} mode is disclosed. Japanese Patent Application Laid-Open No. H11-145704 discloses that, in a substantially rectangular parallelepiped dielectric block, each surface (x
A multi-mode dielectric resonator capable of generating a TM _{01 δ} mode and a TE _{01 δ} mode generated on planes parallel to (−y plane, yz plane, and xz plane) has been proposed.

[0005]

SUMMARY OF THE INVENTION However, multi-stage
In a band-pass filter requiring a resonator,
As described in Japanese Patent Laid-Open No. 7-58516.
Even if the degenerate coupling of the two resonance modes is used,
It is inevitable that the volume occupied by the electrical resonator will increase.
No. Further, Japanese Patent Application Laid-Open No. 11-145704 describes
Even in a triple mode dielectric resonator as shown in FIG.
TM orthogonal to each other_{01 δ}Mode and TE_{01 δ}Mixed modes
The thickness of the dielectric resonator must be adjusted to
Must be matched to the number, which complicates the manufacturing process.
Problem.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, and to realize a dielectric resonator having a very small size and a simple structure while enabling triple mode resonance, and such a dielectric resonator. An object of the present invention is to provide a dielectric filter using a resonator.

[0007]

In order to achieve the object of the present invention, according to the present invention, three resonance modes in one substantially cubic dielectric block are coupled as described in claim 1. A triple mode dielectric resonator having three surfaces formed by shaving three ridges that are not parallel to the dielectric block, wherein the triple mode dielectric resonator is formed. Like that.

[0008] According to a second aspect of the present invention, the above-mentioned 3
It may be formed so as to have another three surfaces formed by shaving the other three ridges facing the ridge.

Further, in the dielectric resonator according to the third aspect,
The three resonance modes are TE _01δ modes.

Further, in the dielectric resonator according to a fourth aspect, the dielectric block is mounted in a hollow, substantially rectangular parallelepiped shield case.

On the other hand, the dielectric filter according to claim 5 is
At least one triple mode dielectric resonator having three surfaces formed by shaving three non-parallel ridges of one substantially cubic dielectric block is provided in the shield case.
This is a triple mode dielectric resonator characterized by being individually mounted.

Further, the dielectric filter according to claim 6 is
Three surfaces formed by cutting three non-parallel ridges of one substantially cubic-shaped dielectric block, and other three ridges facing the three ridges, respectively. A dielectric filter using a triple-mode dielectric resonator, wherein at least one triple-mode dielectric resonator having three surfaces is mounted in a shield case.

In the dielectric filter according to claim 7,
The triple mode is characterized in that a resonance mode generated in the dielectric block is a TE _01δ mode.

In the dielectric filter according to the present invention, a power supply / reception probe is provided near the dielectric block.

Here, the power supply / reception probe may include:
A rod antenna may be used as described, or a loop antenna may be used as described in claim 10.

Further, according to the present invention, there is provided a dielectric resonator of a triple mode having three surfaces formed by cutting three non-parallel ridges of one substantially cubic dielectric block. A duplexer can be configured by combining at least one triple-mode dielectric filter mounted in the shield case for transmission and reception.

[0017]

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

FIG. 1A is a diagram showing a basic structure of a triple mode dielectric resonator according to one embodiment of the present invention, and FIG. 1B is a diagram showing the dielectric structure shown in FIG. It is a figure showing the electric field surface of triple mode resonance in a body resonator.

The dielectric resonator 10 according to the present embodiment has a structure shown in FIG.
As shown in FIG. 1A, the dielectric block is formed of a dielectric block having a substantially cubic shape with three ridges removed, and as shown in FIG. 1B, three electromagnetically independent surfaces m1, m2, m3
To generate a TE _{01 δ} mode. still,
In FIG. 1B, three electromagnetically independent resonance modes are generated on each of the surfaces m1, m2, and m3.
There is an angle of 67.5 degrees between the two and m3 surfaces.

FIG. 1C shows a method of exciting only a single mode (in other words, exciting in a non-coupled state) in the dielectric resonator shown in FIG. 1A. In order to excite only a single mode, as shown in FIG. 1C, for example, the power supply and reception probes 24 and 25 are placed on the opposite surfaces of the dielectric block in the same direction as shown in FIG. It is installed so as to face and excited.

FIG. 2 shows that only a single mode is excited as shown in FIG. 1C (in other words, it is excited in a non-coupled state).
FIG. 9 is a diagram showing pass characteristics and the like in the case. In FIG. 2, the transmission characteristics in this case are indicated by solid lines, and the reflection characteristics are indicated by dotted lines.

As is apparent from FIG. 2, in the triple mode dielectric resonator according to the present embodiment, all three resonance modes are:
It is a TE _{01 δ} mode and has a resonance frequency of about 1.93.
5 [GHz], which is the same.

(Embodiment 1) The dielectric resonator of this embodiment is
3 (a) and 3 (b). FIG. 3 (a) and (b)
FIG. 3 is a view of the same dielectric resonator 10 viewed from different viewpoints. A dielectric block made of a BaO-TiO ₂ dielectric material having a relative dielectric constant εr of 37 was used for the dielectric resonator 10 of the present embodiment.

Now, in order to manufacture the dielectric resonator 10 of this embodiment, a cube (22 mm × 22 m
m × 22 mm), and three ridges sharing one point of the dielectric block composed of a dielectric block surface and surfaces A1, A2,
A3 was cut so as to form an angle of 45 degrees, and as shown in FIG. 3A, the surfaces A1, A2, and A3 were each formed into a flat shape having a width of about 7 mm. As a result, the uncut portions of the three surfaces of the original cube remain, and the surface A
2, a surface B1 adjacent to A3, a surface B2 adjacent to surfaces A1 and A3, and a surface B3 adjacent to surfaces A1 and A2 were formed, respectively. Each of these surfaces B1, B2, and B3 is a square (17 mm × 17 mm) with one side of about 17 mm. Therefore, in this embodiment, the area ratio of each of the surfaces A1, A2, and A3 (referred to as surface A) to each of the surfaces B1, B2, and B3 (referred to as surface B) is about 45%.

Further, as shown in FIG. 3 (b), the surface C facing the surface B (the surface C2 facing the surface B1, the surface C1 facing the surface B3, and the surface C3 facing the surface B2) respectively , 1
This is a shape obtained by cutting out an isosceles triangle having two sides of 5 mm and one side of 7 mm from one corner of a square (22 mm × 22 mm) having a side of 22 mm. Surface A (A1, A2, A
The portion where 3) intersects three planes is formed in the shape of a triangular pyramid. However, there is no problem in characteristics even if the triangular pyramid portion is shaved and made flat.

FIG. 4 is a view for explaining a dielectric filter 20 in which the dielectric resonator 10 of the first embodiment is mounted in a hollow substantially rectangular parallelepiped shield case 21. FIG.
Although the xyz axes are shown separately from the dielectric resonator 10, these x, y, and z axes respectively correspond to two surfaces of the original cubic dielectric block of the dielectric resonator 10. And the relationship is orthogonal. The same applies to the following figures. A hollow rectangular parallelepiped shield case 21 is formed by processing a copper (Cu) plate having a thickness of 1 mm, or forming an aluminum (Al)
The block is manufactured by grinding so as to have a thickness of 3 mm, and FIG. 3A and FIG.
The dielectric resonator 10 shown in FIG.
0 was formed. As shown in FIG. 4, the dielectric filter 20 was provided with two terminals 22 and 23 for power supply / reception probe. Rod-shaped probes were used for the power supply and reception probes 24 and 25. The direction p of the two power supply and reception probes 24 and 25
(Not shown) is parallel to the x-axis with respect to the x-, y-, and z-axes of the dielectric resonator 10;
An angle p ′ (not shown) formed by the angle 25 and the angle 25 is 0 degree.

FIG. 5 shows a pass characteristic of the dielectric filter 20 by a solid line and a reflection characteristic by a dotted line.

As shown in FIG. 5, the dielectric filter 20 of the present embodiment has a frequency of 1.916 [GHz] to 1.934 [GH].
z], it can be seen that a three-stage bandpass filter is formed by the reflection characteristics 51, 52 and 53.

(Embodiment 2) Dielectric resonator 11 of this embodiment
Are shown in FIGS. 6A and 6B. FIGS. 6A and 6B are views of the same dielectric resonator 11 viewed from different viewpoints. Note that the dielectric resonator 1 of the present embodiment
As in Example 1, a dielectric block made of a BaO—TiO 2 dielectric material having a relative dielectric constant εr of 37 was used as in Example 1.

FIG. 6 shows a dielectric resonator 11 of this embodiment.
As shown in (a), three surfaces A (A1, A2, A3) formed by cutting three ridges sharing one point of the dielectric block.
6B, as shown in FIG. 6B, three ridges are formed by further shaving three ridges that share another point on the diagonal line of the one point.
Surfaces A′4, A′5, and A′6 (hereinafter, referred to as surface A ′). In the present embodiment, three surfaces A or three surfaces A ′
And the other three adjacent surfaces B′1, B′2, B′3
[See FIG. 6 (a)] (hereinafter referred to as surface B ') or C'
The angle formed by 1, C'2 and C'3 [see FIG. 6 (b)] (hereinafter referred to as surface C ') is 45 degrees.

Now, in order to manufacture the dielectric resonator 11 of the present embodiment, a cube (22 mm × 22 m
m × 22 mm), and three ridges sharing one point of the dielectric block composed of a dielectric block surface and surfaces A1, A2,
Each of the surfaces A1, A2, and A3 was formed into a plane having a width of about 7 mm as shown in FIG.

Further, three ridges that share another point on the diagonal line of the one point are formed on the surface of the dielectric block and the surface A ′.
4, A'5, and A'6 are cut so as to form an angle of 45 degrees, and as shown in FIG. 6B, the surfaces A'4, A '
5 and A'6 were each formed in a plane having a width of about 7 mm. As a result, the uncut portions of the three surfaces of the original cube remain, and the surfaces B′1 and A adjacent to the surfaces A2 and A3
1, a surface B'2 adjacent to A3 and a surface B'3 adjacent to surfaces A1 and A2 are formed, respectively, and a surface C'1 facing the surface B'3 and a surface C facing the surface B'1 '2 and a surface C'3 facing the surface B'2 were also formed. These faces B
'1, B'2, and B'3 each have a shape in which one corner of a square (17 mm x 17 mm) having a side of about 17 mm is cut. In the surfaces B′1, B′2, and B′3, as a result of the shaving of the corners, in this embodiment, the surface B ′ of the surface A
Is slightly larger than that of the first embodiment, and is about 48%. The area and the shape of the surface C 'facing the surface B' are the same as those of the surface B '.

A dielectric filter similar to that of the first embodiment can be formed by mounting the dielectric resonator 11 of the second embodiment in a hollow, substantially rectangular parallelepiped shield case, as in the first embodiment.

(Embodiment 3) FIG. 7 shows a main part of the dielectric filter of this embodiment. The dielectric filter of the present embodiment has the same dielectric resonator 10 as that of the first embodiment shown in FIGS. 3A and 3B mounted on a hollow, substantially rectangular shield case. FIG. 7 shows only the dielectric resonator 10 and the power supply and reception probes 24 and 25.

With respect to the x, y, and z axes of the dielectric resonator 10, the direction p of the power supply and reception probe 24 fluctuates on the xy plane, and the angle θ1 is 0 degree when parallel to the x axis. Then-
It can be changed in the range of 45 degrees to +45 degrees, and the direction p ′ of the power supply / reception probe 25 fluctuates on the zx plane, and the angle θ2 is 0 degree when parallel to the x axis. Then, it can be changed in the range of -45 degrees to +45 degrees. In the present embodiment, adjustment is made at θ1 = 5 degrees and θ2 = 8 degrees.

(Embodiment 4) FIG. 8A shows a main part of a dielectric filter according to this embodiment. The dielectric filter of the present embodiment has the same dielectric resonator 10 as that of the first embodiment shown in FIGS. 3A and 3B mounted on a hollow, substantially rectangular shield case. FIG. 8A shows only the dielectric resonator 10 and the power supply / reception probes 24 and 25.

In this embodiment, the power supply / reception probes 24 and 2
5 is the surface B of the dielectric resonator 10 [the surface B in FIG.
2] and a plane C (a plane C2 in FIG. 3B). FIG. 8B shows the installation positions of the power supply and reception probes 24 and 25. FIG. 1 is a diagram of the dielectric resonator 10 and the power supply / reception probes 24 and 25 viewed from the x-axis direction. The directions p (not shown) and p '(not shown) of the power supply / reception probes 24 and 25 are parallel to the x-axis, and the power supply / reception probe 24 is in the y-axis direction, as shown in FIG. The power supply / reception probe 25 can be moved in parallel in the z-axis direction.

In FIG. 8B, the power supply / reception probe 24
And 25, the amount of movement in the direction approaching each other is a
(See the figure). Here, as shown in FIG. 8B, a = 0 when the power supply and reception probes 24 and 25 are located on the center line of the dielectric resonator 10, respectively.

In this embodiment, the power supply and reception probes 24 and 2
5 is located on the center line of the dielectric resonator 10 [a = 0], the power feeding probes 24 and 25 move 1 mm in the approaching direction [a = 1 mm], and the power feeding probes 24 and 25 However, the attenuation characteristic of the dielectric filter was measured in three cases, in which the distance moved by 1 mm in the direction away from the object [a = -1 mm]. FIG. 9 shows the attenuation characteristics of the dielectric filter according to the present embodiment. First, as shown in the figure, when a = 0, the attenuation pole 90 is generated at a frequency of about 1.873 [GHz]. Thus, the attenuation pole is obtained on the side of the frequency lower than the center frequency, that is, on the lower band. When the power supply and reception probes 24 and 25 move 1 mm in the approaching direction [a = 1 mm], the attenuation pole 90 is generated at a frequency of about 1.805 [GHz].
That is, compared to the case where a = 0, the frequency shifts to the lower frequency side. Conversely, when the power supply and reception probes 24 and 25 move 1 mm away from each other [a = -1 mm], the attenuation pole 90 occurs at a frequency of about 1.90 [GHz], that is, when a = 0. It can be seen that the movement to the higher frequency side is performed as compared with the case.

(Embodiment 5) In the above embodiments 1 to 4,
Although an example using only one dielectric resonator has been described,
In this example, as shown in FIG. 10A, a dielectric filter 100 having six stages was formed using two dielectric resonators 10. At this time, the number of power supply / reception probes is two.
As described in 4 to 4, the characteristics can be changed.

Although not shown, three or more dielectric resonators 10 may be used. In this case, the characteristics of the dielectric filter can be changed by changing the position and angle of the power supply / reception probe. .

(Embodiment 6) This embodiment is an example in which four dielectric resonators 10 are used as shown in FIG.
The present embodiment is an application example in which a dielectric filter 150 using two dielectric resonators 10 is combined for transmission and reception, and a duplexer 200 is configured.

As described above, the present invention has been described with respect to specific embodiments. However, the present invention is not limited to these embodiments, and is applicable to other embodiments within the scope of the invention described in the claims. You.

For example, in the first to fourth embodiments, the rod-shaped antenna is used as the power supply / reception probe, but the same effect can be obtained by using the loop antenna.

In addition, 3 which shares one point of the dielectric block
Three faces A formed by cutting the ridge, and the other three faces B adjacent
Alternatively, the angle between B ′ and B ′ is set to 45 degrees.
Similar effects can be obtained in the range of 0 degrees. Further, the angle formed between the three surfaces A ′ formed by cutting the three ridges sharing the other point on the diagonal line of the one point and the other three adjacent surfaces C ′ was also set to 45 °, Similar effects can be obtained in the range of 40 degrees to 50 degrees.

Further, the area ratio of the surface A to the surface B is set to about 45.
%, But the same effect can be obtained in the range of 1% to 200%. Further, the area ratio of the surface A to the surface B ′ is about 48%.
However, the same effect can be obtained in the range of 1% to 200%.

[0047]

As described above, the dielectric resonator according to the present invention has a dielectric block in which three ridges of a substantially cubic shape are removed, and three electromagnetically independent surfaces of the dielectric block are provided. Degenerately couples the triple resonance mode (TE _{01 δ} mode) of the same resonance frequency generated in the above, so that it is possible to easily realize a dielectric resonator having an extremely small size and a simple configuration while enabling triple mode resonance. Can be. Further, by mounting the dielectric resonator of the present invention in, for example, a hollow substantially rectangular shield case and providing a power supply / reception probe, it is possible to provide a dielectric filter having a small and simple configuration.

[Brief description of the drawings]

FIGS. 1A and 1B are diagrams illustrating a triple mode dielectric resonator according to an embodiment of the present invention, in which FIG. 1A illustrates a basic structure of the triple mode dielectric resonator, and FIG. ) Is a diagram showing an electric field surface of a triple mode resonance in the dielectric resonator, and (c) is an excitation of only a single mode in the dielectric resonator (in other words, excitation in a non-coupled state). )
It is a figure showing a method.

FIG. 2 is a diagram showing pass characteristics when only the single mode shown in FIG. 1C is excited (in other words, is excited in a non-coupled state).

FIG. 3 is a diagram illustrating a dielectric resonator according to a first embodiment;
(A) is a perspective view of the dielectric resonator viewed from a certain viewpoint, and (b) is a perspective view of the dielectric resonator viewed from a different viewpoint.

FIG. 4 is a diagram illustrating a configuration of a dielectric filter on which the dielectric resonator according to the first embodiment is mounted.

FIG. 5 is a diagram showing transmission and reflection characteristics of the dielectric filter shown in FIG.

FIG. 6 is a diagram illustrating a dielectric resonator according to a second embodiment;
(A) is a perspective view of the dielectric resonator viewed from a certain viewpoint, and (b) is a perspective view of the dielectric resonator viewed from a different viewpoint.

FIG. 7 is a diagram illustrating a relationship between a dielectric resonator and a power supply / reception probe according to a third embodiment.

8A and 8B are diagrams illustrating a relationship between a dielectric resonator and a power supply / reception probe according to a fourth embodiment. FIG. 8A illustrates a main part of the dielectric filter according to the fourth embodiment, and FIG. FIG. 4 is a diagram illustrating a setting position of a probe.

FIG. 9 is a diagram illustrating attenuation characteristics of a dielectric filter according to a fourth embodiment.

10A and 10B are diagrams for explaining a case where a plurality of dielectric resonators are used, wherein FIG. 10A is a diagram illustrating a fifth embodiment in which two dielectric resonators are used, and FIG. FIG. 16 is a diagram illustrating a sixth embodiment in which the resonator is applied to a duplexer using four resonators.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Akihiro Isomura 6-7-1, Koriyama, Taihaku-ku, Sendai City Tokin Co., Ltd. (56) References JP 2001-60805 (JP, A) JP 9-148810 (JP, A) C. Hunter et. a l. , Triple mode die electrical resonator hybrid reflection filter, IEEE proc. Microw, Antennas Prop ag. , Vol. 145, no. 4, 1998, p. 337-343 (58) Field surveyed (Int.Cl. ⁷ , DB name) H01P 1/208 H01P 1/20 H01P 1/213 H01P 7/10 JICST file (JOIS) WPI (DIALOG)

Claims (11)

(57) [Claims] 1. A triple mode dielectric resonator in which three resonance modes in one substantially cubic dielectric block are coupled, wherein three ridges not parallel to the dielectric block are cut off. A triple mode dielectric resonator comprising three surfaces formed by: 2. The dielectric resonator according to claim 1, further comprising another three surfaces formed by shaving the other three ridges facing the three ridges. 3. The method according to claim 1, wherein the three resonance modes are TE _01δ modes.
Item 7. The dielectric resonator according to Item 1. 4. The dielectric resonator according to claim 1, wherein the dielectric block is placed in a hollow, substantially rectangular parallelepiped shield case. 5. At least one triple mode dielectric resonator having three surfaces formed by shaving three non-parallel ridges of one substantially cubic dielectric block is mounted in a shield case. A dielectric filter using a triple mode dielectric resonator, which is disposed. 6. The three surfaces formed by cutting three non-parallel ridges of one substantially cubic dielectric block and the other three ridges facing the three ridges, respectively. Characterized in that at least one triple-mode dielectric resonator having another three surfaces formed by mounting is mounted in a shield case. filter. 7. The dielectric filter according to claim 5, wherein in the triple mode, a resonance mode generated in the dielectric block is a TE _01δ mode. 8. The dielectric filter according to claim 5, further comprising a power supply probe near the dielectric block. 9. The dielectric filter according to claim 8, wherein said power supply and reception probe is a rod-shaped antenna. 10. The dielectric filter according to claim 8, wherein the power supply / reception probe is a loop antenna. 11. A cubic dielectric block formed by shaving three non-parallel ridges of a substantially cubic dielectric block.
A duplexer is formed by combining a triple-mode dielectric filter having at least one triple-mode dielectric resonator having a surface in a shield case for transmission and reception, respectively. Body filter.