JP3801058B2 - Dielectric filter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a small dielectric filter having a structure in which a plurality of dielectric resonators suitable for use in a high frequency band from 5 GHz to 30 GHz are formed in one dielectric block.
[0002]
[Prior art]
With the rapid development of the information communication field, mobile communication systems having a frequency band higher than 2 GHz are being studied. In conventional mobile communications, frequencies up to about 2 GHz band have been used, and a filter combined with a dielectric coaxial resonator has been mainly used as a filter used in a mobile station.
[0003]
However, when the dielectric coaxial resonator is used at a frequency of 5 GHz or more, it is difficult to form a low-loss filter, and it is difficult to reduce the outer shape if a high Q is to be ensured.
[0004]
For these reasons, Japanese Patent No. 2779385 discloses a dielectric filter that does not increase the passage loss even in a frequency band of 3 GHz or higher. A perspective view of this filter is shown in FIG. This is because a plurality of through-holes are formed in a substantially rectangular parallelepiped-shaped dielectric block at a predetermined interval, and a required surface of the dielectric block including the inner surface of the groove is covered with a metal film to form a plurality of TE101 mode dielectrics. A dielectric filter constituting a body resonator.
[0005]
The input / output electrodes 5 provided at both ends of the dielectric filter have the upper end of the input / output electrode connected to the metal film on the upper surface on the release band provided on the side surface, and the lower end of the input / output electrode has the release band. It is formed to be in the middle. An L-shaped metal extraction electrode 13 is attached to the input / output electrode 5 by soldering or the like. The dielectric filter is coupled to an external circuit through the extraction electrode 13.
[0006]
[Problems to be solved by the invention]
However, in this filter, the input / output electrodes and the external circuit are connected via a metal fitting that is a metal extraction electrode. For this reason, the number of parts for external connection increases and there is a concern that the matching (VSWR) with the external circuit varies due to the variation in the metal fitting connection. In addition, when the dielectric filter is mounted on the substrate, adjustment with the external circuit after mounting is necessary, and it is also important as the dielectric filter that the adjustment is easy.
[0007]
Further, as a high-frequency dielectric filter, it is desired that the leakage of electromagnetic waves is reduced, input / output coupling is performed efficiently, and low loss is achieved.
[0008]
The present invention has been made in view of the above-described problems, and the object of the present invention is excellent in board mountability, can be adjusted for matching with an external circuit after mounting, and reduces electromagnetic wave leakage and loss. It is an object of the present invention to provide a dielectric filter including input / output electrodes having efficient input / output coupling.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides an input / output electrode comprising a plurality of resonators formed in one substantially rectangular parallelepiped dielectric block, and comprising an input / output electrode and a dielectric exposed portion in contact with the input / output electrode. A TE mode dielectric filter having a constituent part, a ground electrode formed on the surface of the dielectric block excluding the input / output electrode constituent part, and a coupling part that electromagnetically couples the resonators;
The input / output electrode component and the input / output electrode are formed continuously from the resonator mounting surface at one end of the dielectric filter and one side surface adjacent to the mounting surface, and only the upper end of the input / output electrode on the one side surface. Has a short-circuit point that is electrically connected to the ground electrode.
[0010]
  And the dielectric filter is:The short-circuit point is formed at a position lower than the upper end of the one side surface of the resonator at both ends of the dielectric filter.It is characterized by.
[0011]
In the present invention, the dielectric filter is mounted on an insulator substrate, and a substrate signal line formed on the insulator substrate and a mounting surface portion of the input / output electrodes of the dielectric filter are electrically connected. The present invention relates to the dielectric filter that is connected.
[0012]
In the present invention, there is provided a TE mode dielectric filter in which a plurality of resonators are formed in one dielectric block having a substantially rectangular parallelepiped shape, and input / output from one side surface of the resonator to the mounting surface at both ends of the dielectric filter. By forming an electrode and having a structure in which the upper end of the input / output electrode is electrically connected to the ground electrode on the side surface of the resonator, a special metal fitting is not required for connection to an external circuit as in the prior art, and dielectric is easily performed. The body filter can be mounted on the substrate, and the matching with the external circuit (VSWR) can be made difficult to vary. Also, adjustment with the external circuit after mounting can be easily performed by cutting the input / output electrode portion formed on the side surface of the resonator. Furthermore, the input / output coupling can be efficiently performed by the magnetic field coupling at the resonator side surface portion of the formed input / output electrode and the electric field coupling at the mounting surface portion of the input / output electrode. The area can be reduced, and a low-loss filter with small leakage of electromagnetic waves can be obtained. In particular, by setting the short-circuit point between the input / output electrode and the ground electrode below the upper end of the side surface of the dielectric, the area of the exposed portion of the dielectric can be further reduced, and a low-loss filter can be obtained. In addition, by forming a plurality of TE mode resonators in one dielectric block, the process of attaching the resonators to each other with solder or the like is reduced, thereby reducing the manufacturing cost and the variation in bandwidth due to a deviation in the attaching. Is reduced.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of a dielectric filter according to the present invention will be described with reference to the accompanying drawings. In each embodiment, the same parts and the same parts are denoted by the same reference numerals.
[0014]
  1 is related to the present invention.As a reference exampleIt is a perspective view of one embodiment of a dielectric filter. A dielectric filter 1 according to the present invention includes a plurality of resonators 2 formed in one dielectric block having a substantially rectangular parallelepiped shape, and includes an input / output electrode 5 and a dielectric exposed portion 4 in contact with the input / output electrode. A TE mode dielectric filter having an output electrode component 6, a ground electrode 8 formed on the surface of the dielectric block excluding the input / output electrode component 6, and a coupling unit 3 for electromagnetically coupling the resonators 2 to each other The input / output electrode component 6 and the input / output electrode 5 are continuously formed between the resonator mounting surface 9 at both ends of the dielectric filter and one side surface adjacent to the mounting surface 9. Only the upper end of the input / output electrode 5 has a short-circuit point 7 connected to the ground electrode. As a method of forming the resonator, there is a method of forming a notch (groove) or through-hole 20 between the resonators 2 in the dielectric block and conducting metallization. FIG. 1 shows an example in which a through hole 20 having a long hole formed by conductor metallization is formed between resonators, and FIG. 10 shows an example in which a plurality of through holes are formed between resonators. Further, the structure for forming a plurality of resonators and forming the electromagnetic coupling between the resonators is not limited to the above-described through holes, but also by forming notches (grooves) as shown in FIG. realizable. FIG. 11A shows a filter having a structure in which notches (grooves) 30 are formed between both side surfaces between resonators. FIG. 11B shows a filter having a structure in which a notch (groove) 30 is formed on one side of a side surface between resonators. FIG. 11C shows a filter having a structure in which notches (grooves) 30 are formed between the resonators on the upper and lower surfaces of the resonators. In the filter having such a structure, similar effects can be obtained by adopting the electrode configuration of the present invention in the same manner.
[0015]
In addition, the input / output electrode component 6 and the input / output electrode 5 can be formed on the mounting surface and another side surface adjacent to the mounting surface of the resonator 2 at both ends and parallel to the signal traveling direction.
[0016]
The dielectric filter having the above-described configuration is mounted on a substrate provided with a substrate signal line 11 as shown in FIG. 8, for example, and the mounting surface portion of the input / output electrode 5 and the substrate signal line 11 provided on the substrate 10 are soldered. It can be used by connecting with a conductive adhesive such as. As a result, the dielectric filter can be easily mounted on the substrate without using special parts such as L-shaped metal fittings for mounting. A substrate ground electrode 12 is formed on the substrate 10, and the ground electrode 8 of the dielectric filter and the substrate ground electrode 12 on the substrate are electrically connected. The substrate ground electrode 12 may be formed on the back surface of the substrate. In this case, the substrate ground electrode 12 and the ground electrode 8 of the dielectric filter are electrically connected through a through hole provided in the substrate or a side surface of the substrate. Is done.
[0017]
In addition, after mounting, input / output coupling (VSWR) can be adjusted by partially cutting off the input / output electrodes on the side surfaces of the dielectric. Furthermore, the magnetic field coupling by the electrode on the dielectric side surface and the electric field coupling by the electrode on the mounting surface can be made to work efficiently, and compared with the island-like input / output electrode 5 having no short-circuit point as illustrated in FIG. The exposed area of the ceramic for obtaining the same level of input / output coupling can be reduced, whereby the leakage of electromagnetic waves can be reduced and the loss can be reduced.
[0018]
FIG. 4 is a perspective view of another embodiment of the dielectric filter according to the present invention. The configuration is the same as that of the dielectric filter shown in FIG. 1 except for the input / output electrode pattern. The difference from the embodiment of FIG. 1 is that the short-circuit point 7 between the input / output electrode 5 and the ground electrode 8 is below the upper end of the side surface of the dielectric block (that is, the side surface of the resonator at both ends of the dielectric filter). . As a result, the area of the dielectric exposed portion 4 formed on one side surface of the resonator can be further reduced, and as a result, the loss of the filter can be further reduced. As a result, the cross-sectional area of the coupling portion between the dielectric blocks can be widened, and a wide band filter can be obtained. If the position of the short-circuit point 7 between the input / output electrode 5 and the ground electrode 8 on the side surface of the dielectric block (that is, the side surface of the resonator at both ends of the dielectric filter) is about 3/10 to 7/10 of the side surface height, This is more preferable because strong input / output coupling can be obtained and the exposed area of the dielectric can be reduced appropriately.
[0019]
【Example】
Embodiments of the present invention will be described below with reference to the drawings.
[0020]
(Embodiment 1) The present invention as shown in FIG.As a reference exampleA dielectric filter as one of the embodiments was manufactured as follows, and the characteristics of the filter were measured.
[0021]
The present embodiment is a two-stage filter having a shape of 12.5 × 6.0 × 3.0 mmt. In the central portion of this filter, a long hole 20 for forming electromagnetic coupling between stages is formed by 1.5 mm × 0.5 mmΦ (as shown in FIG. 5 mm, the longest part is rounded at 0.5 mmΦ, and the length in the short side direction is 0.5 mm. One dielectric block has two resonators. An input / output electrode component 6 having a width of 2.4 mm × 3.0 mm is set between the upper and lower ends of the side surfaces of both ends of the filter as shown in FIG. 1, and a 1.2 mm line is formed in the input / output electrode component 6. The input / output electrode 5 having a width was formed, and the dielectric exposed portions 4 were formed on the left and right sides of the input / output electrode 5. The upper end of the input / output electrode 5 is electrically connected to the ground electrode 8 of the resonator at the short-circuit point 7, and the lower end of the input / output electrode 5 is formed to extend to the mounting surface. On the mounting surface, an input / output electrode 5 having a width of 0.8 mm × 0.6 mm is formed in the input / output electrode configuration portion 6 having a width of 2.4 mm × 2.0 mm. A dielectric exposed portion 4 was formed around the input / output electrode 5 formed on the mounting surface except for the connection portion to the side surface portion. In this manner, the dielectric exposed portion 4 was formed in a region other than the input / output electrode 5 in the input / output electrode configuration portion 6. A ground electrode 8 including a through hole 20 for forming inter-stage electromagnetic coupling was formed on the surface of the dielectric filter other than the input / output electrode component 6. Dielectric constant ε of the dielectric material used (dielectric ceramics)_rIs 37.
[0022]
FIG. 2 shows the characteristics of the produced filter. A dielectric filter with a small insertion loss, a center frequency of 5621 MHz, a 3 dB bandwidth of 175 MHz, and a peak point insertion loss of 0.66 dB, was obtained. The unloaded Q (Qu value) of the filter obtained from this was 700. The insertion loss of the filter is inversely proportional to the no-load Q (Qu value) of each resonator constituting the filter and inversely proportional to the bandwidth, and the insertion loss is evaluated without depending on the bandwidth of the filter. It is used as a characteristic. A filter with a large Qu value is an excellent filter with less insertion loss.
[0023]
Input / output electrodes are also provided on the filter mounting surface, facilitating mounting on the board, and a low-loss dielectric filter could be constructed despite the fact that fine adjustment after mounting was possible with the side electrodes. This is probably because the magnetic field coupling by the side electrodes and the electric field coupling by the electrodes on the mounting surface work efficiently in the pattern of the input / output electrodes as in the present invention, and the area of the exposed portion of the dielectric is kept small.
[0024]
FIG. 3 is an experimental example showing that by reducing the exposed area of the dielectric, the unloaded Q (Qu value) increases and the loss decreases. FIG. 3A is a diagram showing a method for measuring the unloaded Q (Qu value) of a dielectric resonator. A sample having a dielectric exposed portion formed on a side surface is placed on a conductor plate, and the sample is placed on both sides of the sample. A coaxial cable in which a loop antenna was formed was installed, a high frequency was applied, a frequency characteristic was measured, and an apparent unloaded Q (Qu value) was calculated.
[0025]
In the sample, the electrode on the side surface of the 5.85 × 5.85 × 3.0 mm TE mode resonator in the 5 GHz band is peeled off in the region of 1.5 mm width × 1.0 mm height at the center (FIG. 3 ( The electrode on the side surface of the resonator having the same shape as in b)) is peeled off in a region of 1.5 mm width × 3.0 mm height at the center (FIG. 3D). Changes in resonance frequency and loss due to electromagnetic wave leakage of each sample are shown in FIG. 3 (c) and FIG. 3 (e).
[0026]
When the electrode on the side surface of the 5.85 × 5.85 × 3.0 mm TE mode resonator in the 5 GHz band is peeled in the region of 1.5 mm width × 1.0 mm height at the center, the resonance frequency is 5712 MHz. On the other hand, in the case of peeling in an area of 1.5 mm width × 3.0 mm height, it was 5631 MHz, a decrease of about 81 MHz. At this time, the Qu value deteriorated from 1050 to about 650. The apparent no-load Q (Qu value) measured is a characteristic of the dielectric, the Q due to the electrode shape, and the Q due to the leakage of electromagnetic waves. In this experiment, the same dielectric material is used. The difference between the measured values is due to the exposed area of the dielectric, and the larger the exposed area of the dielectric, the greater the leakage of electromagnetic waves. This indicates that the insertion loss increases.
[0027]
(Example 2)
In order to further reduce the leakage of electromagnetic waves, an embodiment of a dielectric filter in which the short-circuit point 7 between the input / output electrode 5 and the ground electrode 8 is set to a position lower than the upper end of the side surface as shown in FIG.
[0028]
In this embodiment, the position of the short-circuit point 7 is set to 1/2 the height of the dielectric block side surface (1.5 mm height from the mounting surface), and the size of 12.5 × 6.0 × 3.0 mmt. A two-stage filter was produced.
[0029]
  In the center of this filter, a through hole 20 for forming electromagnetic coupling between stages was formed with a size of 1.5 × 0.5 mmΦ. 2.4mm width on the side of the resonator at both ends of the filter1.5The input / output electrode component 6 having a height of mm was set from the side of the mounting surface, and the input / output electrode 5 having a line width of 1.2 mm was formed in the input / output electrode component 6. Further, on the mounting surface, an electrode having a width of 1.2 mm × 1.2 mm was formed in the input / output electrode component 6 having a width of 2.4 mm × 2.0 mm, as shown in FIG. In this manner, the dielectric exposed portion 4 was formed in a region other than the input / output electrode 5 in the input / output electrode configuration portion 6. A ground electrode was formed on the surface of the dielectric filter other than the input / output electrode component 6 including a long hole 20 through which electromagnetic coupling between stages was formed. Dielectric constant ε of the dielectric material used_rIs 37.
[0030]
FIG. 5 shows the characteristics of the dielectric filter fabricated in this way. A center frequency of 5818 MHz, a 3 dB bandwidth of 168 MHz, and a peak point insertion loss of 0.45 dB were obtained. The Qu value obtained from this was 900.
[0031]
As can be seen from this example, by forming an input / output electrode structure having a short-circuit point 7 with the ground electrode 8 in the middle of the side surface of the resonator at both ends of the dielectric filter, the short-circuit point 7 with the ground electrode 8 is formed. Compared with the filter provided at the upper end of the side surface, the leakage of electromagnetic waves is small, and the filter can be further reduced in loss.
[0032]
Furthermore, in the dielectric filter having through holes between the resonators as described above, the magnitude of electromagnetic coupling between the resonators is changed by changing the size (diameter and length) of the through holes. And a filter with a desired bandwidth can be formed. For example, by increasing the through hole of this embodiment to 1.5 mm × 0.5 mmΦ, the electromagnetic coupling between the resonators is reduced, and a filter having a center frequency of 5528 MHz and a bandwidth of 56 MHz is obtained.
[0033]
(Comparative Example 1)
For comparison, the configuration of the dielectric filter of Example 2 other than the input / output electrode components is made the same, and the input / output electrode components are not island-like with a short-circuit point with the ground electrode as shown in FIG. A dielectric filter having a pattern of the input / output electrode 5 was formed. At this time, the same input / output impedance was set.
[0034]
The input / output electrode component 6 and the input / output electrode 5 of this comparative example are 2.4 mm wide × 1.5 mm high on one side of the resonator at both ends of the dielectric filter. In addition, an input / output electrode 5 having a width of 1.2 mm and a height of 0.8 mm was formed therein. Further, on the mounting surface of the resonator, the input / output electrode component 6 having a size of 2.4 mm depth × 2.0 mm width and the input / output electrode 5 having a depth of 1.5 mm × 1.2 mm width are formed therein. did.
[0035]
FIG. 7 shows the characteristics of the dielectric filter having the configuration shown in FIG. A center frequency of 5710 MHz, a 3 dB bandwidth of 100 MHz, and a peak point insertion loss of 1.58 dB were obtained. The Qu value obtained from this was 500.
[0036]
As can be seen from the comparison between Example 2 and Comparative Example 1, the input / output electrode structure has a short-circuit point 7 to the ground electrode on one side surface of the resonator at both ends of the dielectric filter, in particular, the short-circuit point 7 is a dielectric. In the input / output electrode structure at a position lower than the upper end of the body side surface, a dielectric filter having a large input / output coupling, a small insertion loss, and a wide relative bandwidth is obtained as compared with an input / output electrode structure having no short-circuit point 7. Can do. That is, when the through holes between the resonators are made the same and the area of the coupling portion 3 is made the same, the area of the dielectric exposed portion 4 of the electrode structure of the present invention can be further reduced, and the insertion loss can be further reduced. it can.
[0037]
In addition, when the area of the dielectric exposed portion of the input / output electrode component is the same, the electrode structure of the present invention has a small input / output impedance and a small through hole between the resonators to increase the area of the coupling portion 3. As a result, it is possible to have a wide specific bandwidth, so that the insertion loss can be reduced.
[0038]
(Example 3)
FIG. 8 shows an example in which the high-frequency dielectric filter of the present invention is mounted on a substrate, and the input / output electrodes on the mounting surface are electrically connected to the extraction electrode formed on the substrate.
FIG. 8A is a diagram showing an embodiment in which a dielectric filter is mounted on a substrate, and FIG. 8B is a diagram showing a substrate 10 and a dielectric filter in which a substrate signal line 11 and a substrate ground electrode 12 are formed. FIG.
[0039]
As the substrate 10, a 10 mm × 20 mm × 0.4 mmt Teflon (R) substrate is used, and an extraction electrode connected to an input / output electrode of a dielectric filter and connected to an external circuit as shown in FIG. The substrate signal line 11 having a width of 1.17 mm and the substrate ground electrode 12 connected to the ground electrode of the dielectric filter are formed. By applying paste solder on the substrate, placing a dielectric filter thereon, and using a reflow oven, the input / output electrodes on the mounting surface of the dielectric filter and the substrate signal line 11 of the substrate are electrically bonded with solder. A 22 GHz band two-stage dielectric filter was mounted on the substrate 10.
[0040]
The dielectric filter used in this example is a two-stage filter having a size of 3.00 mm × 8.88 mm × 1.5 mmt, using dielectric ceramics having a relative dielectric constant of 9.6, and through holes 20 of the filter. The size of the input / output electrode component on the side is 1.5 mm width × 0.7 mm height, and the size of the input / output electrode 5 is 0.5 mm. The line width, and on the mounting surface side, the input / output electrode component is 1.4 mm wide × 1.0 mm deep, and the input / output electrode 5 is 0.8 mm wide × 0.6 mm deep. . Other than that, the configuration is the same as in the second embodiment.
[0041]
FIG. 9 shows the characteristics of the dielectric filter installed on the substrate having the configuration shown in FIG. The center frequency was 22350 MHz, the 3 dB bandwidth was 450 MHz, and the insertion loss at the peak point was 1.10 dB. The Qu value obtained from this was 850, and a dielectric filter with a small insertion loss was obtained.
[0042]
In this way, the dielectric filter can be easily attached to the substrate by bonding the input / output electrodes on the mounting surface side of the dielectric filter having the input / output electrode pattern of the present invention and the substrate signal line with a conductive adhesive such as solder. It can be seen that a dielectric filter with low insertion loss can be easily obtained even when mounted on a substrate.
[0043]
(Example 4)
FIG. 12 shows an embodiment in which the structure shown in FIG. 10 is applied to a three-stage filter. Using a material having a relative dielectric constant of 24, a three-stage filter having a shape of 11.73 mm × 4.0 mm × 2.0 mmt is formed, and a 0.8 mmφ through-hole 20 for forming electromagnetic coupling between the stages is formed in the center of the filter. Were formed with an interval of 1.0 mm. On the side surfaces of the resonators at both ends of the filter, an input / output electrode component 6 having a width of 2.0 mm × 1.0 mm is set from the mounting surface side of the side surface, and a 0.7 mm line is formed in the input / output electrode component 6. An input / output electrode 5 having a width was formed. On the mounting surface, an input / output electrode 5 of 1.5 mm width × 0.9 mm depth was formed in the input / output electrode configuration part 6 of 2.4 mm width × 1.5 mm depth. This three-stage filter is mounted on a 10 mm × 20 mm × 0.4 mmt Teflon (R) substrate having a signal line and a ground electrode formed on the surface, and the 1.17 mm signal line on the substrate and the input / output electrode 5 of the filter The mounting surface portion was electrically short-circuited with solder.
[0044]
FIG. 13 shows the characteristics of the dielectric filter fabricated in this way. A center frequency of 11610 MHz, a 3 dB bandwidth of 78 MHz, and a peak point insertion loss of 2.79 dB were obtained. The Qu value obtained from this was 1050, which was larger than the Qu value of the conventional filter.
[0045]
(Example 5)
FIG. 14 shows an embodiment in which the structure of FIG. 4 is applied to a three-stage filter. Using a material with a relative dielectric constant of 9.6, a three-stage filter having a shape of 10.23 mm × 3.00 mm × 1.5 mmt is formed, and 0.8 mm × 0 for forming electromagnetic coupling between the stages in the center of the filter. A conductive long hole 20 having a diameter of 5 mmφ was formed. On the side surfaces of the resonators at both ends of the filter, an input / output electrode component 6 having a width of 1.5 mm × 0.8 mm is set from the mounting surface side of the side surface, and a 0.55 mm line is formed in the input / output electrode component 6. An input / output electrode 5 having a width was formed. Further, on the mounting surface of the resonator, an input / output electrode 5 having a width of 0.8 mm and a depth of 0.6 mm was formed in the input / output electrode constituting part 6 having a width of 1.4 mm and a depth of 1.0 mm. This three-stage filter is mounted on a 10 mm × 20 mm × 0.4 mmt Teflon (R) substrate having a signal line and a ground electrode formed on the surface, and the 1.17 mm signal line on the substrate and the input / output electrode 5 of the filter The mounting surface portion was electrically short-circuited with solder.
[0046]
FIG. 15 shows the characteristics of the dielectric filter fabricated in this way. A center frequency of 21900 MHz, a 3 dB bandwidth of 360 MHz, and a peak point insertion loss of 2.08 dB were obtained. The Qu value obtained from this is 850, which is larger than the Qu value of the conventional filter.
[0047]
【The invention's effect】
As apparent from the above description, in the present invention, the input / output electrodes are formed from one side surface of the resonator to the mounting surface at both ends of the dielectric filter, and the upper end of the input / output electrode is formed on the side surface of the resonator. By adopting a structure that is electrically connected to the ground electrode, input / output coupling can be efficiently performed, so that the area of the dielectric exposed portion can be reduced, and a low-loss filter with small leakage of electromagnetic waves can be obtained. In particular, by setting the short-circuit point between the input / output electrode and the ground electrode below the upper end of the side surface of the dielectric, the area of the exposed portion of the dielectric can be further reduced, and a low-loss filter can be obtained.
[0048]
In addition, the above-described structure eliminates the need for special metal fittings for connection to an external circuit as in the prior art, and makes it difficult to vary the matching (VSWR) with the external circuit. It can be a filter.
[0049]
Also, adjustment with the external circuit after mounting can be easily performed by cutting the input / output electrode portion formed on the side surface of the resonator.
[0050]
Further, by forming a plurality of TE mode resonators in one dielectric block, the process of attaching the resonators to each other with solder or the like is reduced, and the manufacturing cost is reduced and the bandwidth varies due to a deviation in the application. Is reduced.
[Brief description of the drawings]
FIG. 1 of the present inventionAs a reference exampleIt is an external view which shows one Embodiment of a dielectric material filter.
FIG. 2 is a characteristic diagram of the dielectric filter of FIG.
FIG. 3 is an explanatory diagram showing a relationship between an exposed area of a dielectric and a Qu value.
FIG. 4 is an external view showing another embodiment of the dielectric filter according to the present invention.
FIG. 5 is a characteristic diagram of the dielectric filter of FIG. 4;
FIG. 6 is an external view showing an embodiment of a dielectric filter as a comparative example in which an input / output electrode having no short-circuit point with a ground electrode is formed.
FIG. 7 is a characteristic diagram of the dielectric filter of FIG.
FIG. 8 is an external view showing an embodiment in which a dielectric filter according to the present invention is mounted on a substrate.
9 is a characteristic diagram of a dielectric filter mounted on the substrate of FIG.
FIG. 10 is an external view showing another embodiment of the dielectric filter according to the present invention.
FIG. 11 is an external view showing another embodiment of the dielectric filter according to the present invention.
FIG. 12 shows another embodiment of the dielectric filter according to the present invention.
FIG.
13 is a characteristic diagram of the dielectric filter of FIG.
FIG. 14 is an external view showing another embodiment of the dielectric filter according to the present invention.
FIG. 15 is a characteristic diagram of the dielectric filter of FIG.
FIG. 16 is an external perspective view showing a conventional dielectric filter.

Claims (2)

A plurality of resonators are formed in one dielectric block having a substantially rectangular parallelepiped shape, excluding the input / output electrode configuration unit including the input / output electrode and the dielectric exposed portion in contact with the input / output electrode. A TE mode dielectric filter having a ground electrode formed on the surface of the dielectric block and a coupling part for electromagnetically coupling the resonators, wherein the input / output electrode component and the input / output electrode are the dielectric are formed continuously toward the one side surface adjacent to the mounting surface and the mounting surface of the cavity of the filter ends, it has a short-circuit point only the upper end of the input and output electrodes of said one side is electrically connected to the ground electrode, the short A dielectric filter characterized in that a point is formed at a position lower than the upper end of the one side surface of the resonator at both ends of the dielectric filter. The dielectric filter is placed on an insulator substrate, and a substrate signal line formed on the insulator substrate is electrically connected to a mounting surface portion of an input / output electrode of the dielectric filter. The dielectric filter according to claim 1 .

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