JPH0466122B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a dielectric resonator device that utilizes resonance of TM ₁₁₀ mode (hereinafter simply referred to as TM ₁₁₀ mode) in a rectangular cavity.

(Prior art and its problems) As a filter using TM ₁₁₀ mode,
There is one known in Japanese Patent No. 53-119650. In such a filter, a necessary number of stages are combined to form a single stage resonator, each of which has a linear cylindrical or prismatic dielectric inside a case that functions as a shielding case.

This has limited the ability to meet the eternal demands of the telecommunications equipment industry for miniaturization and lower prices.

Furthermore, channel filters are used, for example, in shared transmission equipment for mobile phone base stations. This channel filter, as shown in Figure 10,
Multiple filters F ₁ , F ₂ , which pass only the signals of the multiple channels CH 1 , CH ₂ , ..., _{CH o} ,
..., the structure is such that the output side of F _o is connected with a cable, etc. Each filter uses a cavity resonator, a TE ₀₁₈ dielectric resonator, or a TM ₀₁₀ dielectric resonator. In any case, since the configuration is a combination of a plurality of filters each configured in the form of one for each channel, there has been a strong demand for miniaturization.

(Object of the Invention) Therefore, an object of the present invention is to provide a small and low-cost dielectric resonator device for use in, for example, a channel filter.

(Means for Solving the Problems) In order to achieve the above object, the present invention integrates three columnar dielectrics in a rectangular parallelepiped cavity shielding case in a state perpendicular to each other. The axial direction of one of the columnar dielectrics is Z
A dielectric resonator that utilizes TM ₁₁₀ mode resonance, TM ₀₁₁ mode resonance, and TM ₁₀₁ mode resonance in a rectangular coordinate system aligned with the axis, and an external coupling means for coupling this dielectric resonator to an external circuit. In the dielectric resonator device comprising a dielectric resonator device, the external coupling means is first to fourth coupling means disposed within a rectangular parallelepiped cavity shield case and each comprising a magnetic coupling loop; Each of the magnetic coupling loops of the first to third coupling means among the fourth coupling means interlinks only with the lines of magnetic force generated respectively surrounding the three columnar dielectrics, while the magnetic coupling loops of the fourth coupling means The coupling loop is characterized in that it interlinks with any of the lines of magnetic force generated surrounding the three columnar dielectric bodies.

(Function) 3, which is the lowest order resonance mode of the rectangular parallelepiped cavity resonator.
A solid dielectric material whose permittivity is overwhelmingly larger than that of air exists in the direction of each electric field line of the heavily degenerate TM ₁₁₀ mode. This reduces the external dimensions of the dielectric resonator device. The signal input to the first external coupling means is output from the fourth external coupling means. Furthermore, the signal input to the second external coupling means is output from the fourth external coupling means. Furthermore, the signal input to the third external coupling means is input from the fourth external coupling means. Of course, you can also use it in the opposite way,
The signal input to the fourth external coupling means is output from the first to third external coupling means according to the resonant frequency of each dielectric resonator.

(Example) FIG. 1 is a perspective view showing the main parts of the present invention. In the figure, 1 is a rectangular parallelepiped cavity shield case, and 2 is a composite dielectric in which three columnar dielectrics (the illustrated example is a columnar dielectric with a square cross section) 2a, 2b, and 2c are integrated in a state in which they are perpendicular to each other. It is. It should be noted that the illustrated composite dielectric is shown in an ideal shape with partial deformation performed due to processing technology omitted.
The case 1 may be a metal case, or a case in which a shield electrode film is provided on the inner or outer surface of a rectangular parallelepiped cavity made of the same (ZrSn)TiO ₄ ceramic as the composite dielectric 2, for example. In any case, both axial ends of the composite dielectric must maintain good contact with the case 1 or the shield electrode film.
As the composite dielectric 2, (ZrSn)TiO ₄ ceramic was used. The dielectric constant (ε) is 37.5, and the material temperature coefficient (η _F =−α−1/2ηε) is 0±0.5 ppm/°C.

With this configuration, while inheriting the advantages of conventional filters using TM ₁₁₀ mode, such as high no-load Q and small size, it is possible to maintain the same characteristics as conventional filters using TM ₁₁₀ mode. The volume of the resonator device can be reduced to 1/3 compared to the previous model.

By the way, as shown in Figures 2 to 4,
Differences from the present invention will be discussed by considering a case in which a rectangular cavity is provided with a composite dielectric 3 in which two columnar dielectrics 3a and 3b are integrated in a cross shape in a state in which they are orthogonal to each other.

With the configuration shown in Figures 2 to 4, the second
Electric lines of force run in the X-axis direction as shown in the figure.
A dielectric material 3 is used in the TM ₁₁₀ mode and the TM ₁₁₀ mode in which electric lines of force run in the Y-axis direction as shown in Figure 3.
a and 3b come into play effectively. However, at the same time, the higher-order mode as shown in FIG. 4 also exists at almost the same frequency as the above-mentioned fundamental mode, which has the drawback of making it difficult to put it into practical use.

If such a configuration is referred to as a dual mode resonator, a configuration such as that of the present invention is referred to as a triple mode resonator.

In this triple mode resonator, the electric lines of force in the higher mode run not only in the X-axis and Y-axis directions but also in the Z-axis direction, so the frequency is considerably lower than that of the fundamental mode and can be ignored in practical use. A triple mode resonator is advantageous in this respect.

Now, when a product is manufactured by implementing the present invention, the electromagnetic fields of the three TM ₁₁₀ modes may interfere with each other due to processing technology. In this case, take measures as shown in FIG.

That is, in FIG. 5, the columnar dielectric 2
In order to prevent the electromagnetic fields of the TM ₁₁₀ modes involving a and 2b from interfering with each other, a coupling adjustment consisting of a pair of screw-shaped metal bodies is provided in a plane that includes both columnar dielectric bodies 2a and 2b. member 4a,
5a may be made to protrude into the case from the ridges 6a, 7a of the case 1.

The columnar dielectrics 2a and 2b are involved, respectively.
When discussing the combination of TM ₁₁₀ modes, the 6th
Let us consider odd mode and even mode as shown in FIG. What is shown is the distribution of electric lines of force.

The average value of the electromagnetic energy currently stored in the resonant system is W~ _t , the magnetic energy contained in the minute part into which the metal is inserted is △W~ _n , and the electric energy contained in the minute part into which the metal is inserted is △. When W~ _e , Δω/Δω ₀ =(ΔW~ _n −ΔW~ _e )/W~ _t .

As you can see from this perturbation equation, inserting a metal in an area with a strong magnetic field will increase the frequency, and inserting a metal in an area with a strong electric field will decrease the frequency.

Therefore, regarding the odd mode shown in FIG. 6, the magnetic energy is stronger than the electric energy near the coupling adjustment member 4a, and conversely, the electric energy is stronger than the magnetic energy near the coupling adjustment member 5a. Therefore, when the degree of insertion of the coupling adjustment member 4a is increased, the resonance frequency of the odd mode increases, and when the degree of insertion of the coupling adjustment member 5a is increased, the resonance frequency of the odd mode is decreased.

Furthermore, in the even mode shown in FIG. 7, the connection adjustment member 4 is opposite to the odd mode.
The electric energy is stronger than the magnetic energy near a, and the magnetic energy is stronger than the electric energy near the coupling adjustment member 5a. Therefore, when the degree of insertion of the coupling adjustment member 4a is increased, the resonance frequency of the even mode decreases, and when the degree of insertion of the coupling adjustment member 5a is increased, the resonance frequency of the even mode is increased.

From the above, if the resonance frequency of the odd mode and the resonance frequency of the even mode are made equal by moving the coupling adjustment members 4a and 5a in and out,
The coupling is effectively zero.

In addition, in order to prevent the electromagnetic fields of the TM ₁₁₀ mode involving the columnar dielectrics 2b and 2c from interfering with each other, the coupling adjustment member 4a is placed in a plane including both the columnar dielectrics 2b and 2c. ,5a
It is preferable to make connection adjustment members 4b, 5b similar to the above project from the ridges 6b, 7b of the case 1 into the case.

Furthermore, in order to prevent the electromagnetic fields of the TM ₁₁₀ mode involving the columnar dielectrics 2c and 2a from interfering with each other, these columnar dielectrics 2c and 2a are
The connection adjustment members 4a, 5
Connection adjustment members 4c, 5c similar to a, 4b, 5b
It is preferable to make them project into the case from the ridges 6c and 7c of the case 1.

The point is to consider the aforementioned odd mode and even mode and place the coupling adjustment member at a position that affects these modes. Therefore, they do not necessarily have to be a pair. The coupling adjustment member may be a dielectric material coated with a metal film.

If the three modes are prevented from interfering with each other in this way, three electrically orthogonal resonators are accommodated in one case.

Now, such a resonator is put into practical use by being provided with means for coupling with an external circuit.

As shown in FIGS. 8A to 8C, the axial direction of the columnar dielectric 2a, the axial direction of the columnar dielectric 2b, and the axial direction of the columnar dielectric 2c are respectively expressed by X in the orthogonal coordinate system.
When aligned with axis, Y axis, and Z axis, loop 8c
are arranged near one end of the columnar dielectric 2b with a distance from the surface of the columnar dielectric 2b in the X-axis direction. At this time, the plane containing the loop 8c is
Make it perpendicular to the axis. One end of the loop 8c is connected, for example, to the center conductor of the coaxial connector 10c, and the other end is grounded.

An input signal applied to the input coaxial connector 10c causes a current to flow through the loop 8c, and the direction of the generated magnetic lines of force, the direction of the magnetic lines of force MF ₁ in the resonance mode involving the columnar dielectric 2a, and the resonance involving the columnar dielectric 2b. The direction of the magnetic field line MF ₂ of the mode and the magnetic field line MF ₃ of the resonance mode involving the columnar dielectric 2c
When observing the directions of , only the magnetic field line MF ₃ has the same direction component and is coupled.

Therefore, if a frequency component of a resonance mode involving the columnar dielectric 2c is present in the signal applied to the input coaxial connector 10c, a resonance phenomenon occurs.

Similar coupling means are provided for the columnar dielectric 2b. The loop 8b is arranged near one end of the columnar dielectric 2a with a distance from the surface of the columnar dielectric 2a in the Z-axis direction. At this time, loop 8
The plane containing b is made perpendicular to the Z axis. One end of the loop 8b is connected to the coaxial connector 1, for example.
Connect to the center conductor of 0b, and ground the other end.

An input signal applied to the input coaxial connector 10b causes a current to flow through the loop 8b, and the direction of the generated magnetic lines of force, the direction of the magnetic lines of force MF ₁ in the resonance mode involving the columnar dielectric 2a, and the resonance involving the columnar dielectric 2b. The direction of the magnetic field line MF ₂ of the mode and the magnetic field line MF ₃ of the resonance mode involving the columnar dielectric 2c
When observing the directions of , only the magnetic field line MF ₂ has a component in the same direction and is coupled.

Therefore, if a frequency component of a resonance mode involving the columnar dielectric 2b is present in the signal applied to the input coaxial connector 10b, a resonance phenomenon occurs.

Furthermore, similar means are provided for the columnar dielectric 2a. The loop 8c extends from the surface of the columnar dielectric 2c near one end of the columnar dielectric 2c.
Place them at intervals in the axial direction. At this time, the plane including the loop 8a is made perpendicular to the Y axis. One end of the loop 8a is connected, for example, to the center conductor of the coaxial connector 10a, and the other end is grounded.

An input signal applied to the input coaxial connector 10a causes a current to flow through the loop 8a, and the direction of the generated magnetic lines of force, the direction of the magnetic lines of force MF ₁ in the resonance mode involving the columnar dielectric 2a, and the resonance involving the columnar dielectric 2b. The direction of the magnetic field line MF ₂ of the mode and the magnetic field line MF ₃ of the resonance mode involving the columnar dielectric 2c
When observing the directions of , only the magnetic field line MF ₁ has a component in the same direction and is coupled.

Therefore, if a frequency component of a resonance mode involving the columnar dielectric 2a is present in the signal applied to the input coaxial connector 10a, a resonance phenomenon occurs.

Then, the position where it is coupled to any of the lines of magnetic force MF ₁ in the resonance mode involving the columnar dielectric 2a, the lines MF ₂ in the resonance mode involving the columnar dielectric 2b, and the lines MF ₃ in the resonance mode involving the columnar dielectric 2c. Loops 12a, 12b, and 12c are placed in the loops 12a, 12b, and 12c.

In the example shown in FIG. 8, loops 12a, 12b,
12c is the corner 1 where the three ridges of case 1 meet
4 are placed near each other. And loop 12a
If the plane containing the loop 12b is defined as an arbitrary first plane including the corner 14 and the center of the case, then the plane containing the loop 12b intersects this first plane at an intersection angle of 120°, and its axis of intersection is at an angle of 120°. 14 and the case center, and the plane including the loop 12c intersects the first and second planes at an intersection angle of 120 degrees, and the intersection angle is a third plane passing through the corner 14 and the case center. becomes the plane of

One end of each loop 12a, 12b, 12c is connected together to the center conductor of coaxial connector 16, and the other end of each loop 12a, 12b, 12c is grounded. In the loop 12a, magnetic field lines MF ₁ , MF ₂ ,
All of the magnetic lines of force MF ₃ are interlinked, and similarly, all of the lines of magnetic force MF ₁ , MF ₂ , and MF ₃ are interlinked with the loops 12b and 12c.

Rotating the loops 12a, 12b, 12c about an axis passing through the corner 14 and the case center changes the output characteristics. In this way, the coaxial connector 10
The signals applied to a, 10b, and 10c are outputted from the same connector 16.

The shapes of the loops 8a to 8e and loops 12a to 12c are not limited to those shown in the drawings, and may be ring-shaped, for example.

The embodiment device is represented by a lumped constant circuit as shown in Fig. 9A.
Alternatively, it may be as shown in FIG. 9B. It is currently unknown which one is faithful to the actual three-dimensional circuit. In FIGS. 9A and 9B, R ₁ is a resonator related to a resonance mode involving the columnar dielectric 2a, R ₂ is a resonator related to a resonance mode involving the columnar dielectric 2b, and R ₃ is a columnar dielectric. 2
This is a resonator related to a resonance mode involving c.

The resonant frequencies of each resonator may be the same or different.

Although the embodiment has been described assuming a channel filter or a power combiner, this device can also be used as a duplexer.

(Effects) As is clear from the above embodiments, this invention effectively utilizes the three mutually orthogonal TM ₁₁₀ modes existing in the rectangular parallelepiped cavity shield case, so it is compact to 1/3 of the conventional size. This is an epoch-making technology that can be used to reduce costs. Furthermore, since the power distribution or synthesis circuit portion is also present within the case, the product of the present invention is considerably smaller than the conventional example.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the main part of an embodiment of the present invention, FIGS. 2, 3, and 4 are explanatory diagrams explaining dual mode resonance, and FIG. 5 is a main part of an embodiment of the invention. FIGS. 6 and 7 are explanatory diagrams illustrating an embodiment of the present invention. FIGS. 8A, B, and C are internal explanatory diagrams of an embodiment of this invention. FIGS. 9A and B 1 is an equivalent circuit diagram of an embodiment of the present invention, and FIG. 10 is an explanatory diagram of a conventional example. 1... Shield case, 2... Composite dielectric, 8a,
8b, 8c, 12...Magnetic coupling loop.

Claims (1)

[Claims] 1. Three columnar dielectrics are integrated in a rectangular parallelepiped cavity shielding case in a state perpendicular to each other, and the axial direction of one of the three columnar dielectrics is the Z axis. In a rectangular coordinate system that matches
TM ₁₁₀ mode resonance, TM ₀₁₁ mode resonance and
In a dielectric resonator device comprising a dielectric resonator that utilizes TM ₁₀₁ mode resonance and an external coupling means for coupling this dielectric resonator to an external circuit, the external coupling means is a rectangular parallelepiped cavity shield. first to fourth coupling means disposed within the case and each comprising a magnetic coupling loop;
Each of the magnetic coupling loops of the coupling means interlinks only with the lines of magnetic force generated surrounding the three columnar dielectrics, while the magnetic coupling loop of the fourth coupling means surrounds the three columnar dielectrics. A dielectric resonator device characterized in that it interlinks with each of the lines of magnetic force generated.