A dielectric filter and a radio transceiver device including the dielectric filter

Abstract

The dielectric filter provided by the present invention realizes capacitive coupling through the combined action of a negative coupling groove and a partition ring. By arranging the negative coupling groove on the upper surface of the dielectric filter body, the negative coupling groove has openings on both the upper surface and the front surface of the dielectric filter body. When the ceramic material is sintered at a high temperature, the shape and precision of the negative coupling groove change little, and the influence on the electrical performance of the dielectric filter is small. By arranging the partition ring on the lower surface of the dielectric filter body and making the partition ring directly below the negative coupling groove, the partition ring can compensate for the above influence, so that the electrical performance of the dielectric filter is more stable and the yield rate is high. In addition, due to the existence of the partition ring, the depth of the negative coupling groove does not need to be too deep, so that the volume of the negative coupling groove accounts for a small proportion in the entire dielectric filter, and the structural strength of the dielectric filter is better. The present invention also provides a radio transceiver including the above dielectric filter.

Description

Technical Field

[0001] The present invention relates to the field of electronic communication equipment, and in particular to a dielectric filter and a radio transceiver comprising the dielectric filter. Background Art

[0002] With the advent of the "big bang" era of 5G communication, 5G base stations are gradually becoming popular around the world, and filters are the key components in communication base stations that determine the anti-interference characteristics of base stations. Traditional 4G base stations use aluminum cavity filters to make bulky cavity filters, which cannot be used on a large scale under the architecture of Massive MIMO of 5G base stations due to defects such as size, weight, and cost. Dielectric filters, however, have become the preferred solution for filters for 5G base stations due to their small size, low loss, low cost, and high reliability. At the same operating frequency, dielectric filters can reduce the overall filter volume and weight to a few tenths of traditional cavity filters by virtue of the volume compression effect brought by high dielectric constants, while maintaining good performance. With the occupation of radio spectrum resources and the improvement of base station performance requirements, strict requirements are placed on the out-of-band suppression indicators of filters. At present, the common solution in the industry is to use a cross-coupling structure to construct a transmission zero point outside the filter band, so that the rectangular coefficient of the filter can be improved and the suppression of out-of-band spurious can be increased.

[0003] When the filter constructs a cross-coupled transmission zero point, negative coupling is usually required to flip the filter transmission phase. For example, Chinese patent application CN110444849A discloses a dielectric filter with a long blind slot negative coupling structure. In order to meet some specific electrical performance requirements, for example, when the relative bandwidth of the filter is about 5%, the depth of the blind slot negative coupling needs to be designed to be very deep, and the ratio of the slot depth to the total height of the filter reaches about 95%; at the same time, the length of the blind slot is relatively long, and the shape and precision of the blind slot change greatly when the ceramic material is sintered at high temperature, which will cause a significant change in the shape and precision of the negative coupling structure of the dielectric filter, thereby affecting the electrical performance of the dielectric filter and reducing the yield rate; at the same time, the deeper blind slot also greatly reduces the structural strength of the dielectric filter, which is prone to cracking and leads to a decrease in the reliability of the filter. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a dielectric filter that realizes capacitive coupling through the combined action of a negative coupling groove and a partition ring. When the ceramic material is sintered at a high temperature, the shape and precision of the negative coupling groove change little, and the impact on the electrical performance of the dielectric filter is small. The partition ring can also be used to compensate for the above-mentioned impact, so that the electrical performance of the dielectric filter is more stable, the yield rate is high, and the structural strength is better. The present invention also provides a radio transceiver including the dielectric filter.

[0005] To achieve the above object, the technical solution adopted by the present invention is a dielectric filter, comprising at least two dielectric resonators, wherein the dielectric resonator comprises a dielectric resonator body made of ceramic material and a debugging hole located on the upper surface of the dielectric resonator body, wherein the debugging hole is a blind hole and is used to debug the resonant frequency of the dielectric resonator in which the debugging hole is located; all the dielectric resonator bodies constitute a dielectric filter body, and the dielectric filter further comprises:

[0006] A negative coupling slot, the negative coupling slot is located on the upper surface of the dielectric filter body and at the connection position of two adjacent dielectric resonators, the negative coupling slot is a blind slot, the negative coupling slot has an opening on the upper surface of the dielectric filter body, and the negative coupling slot also has an opening on the front surface of the dielectric filter body;

[0007] A conductive layer covering the surface of the dielectric filter body, the inner wall surface of the debugging hole and the inner wall surface of the negative coupling groove;

[0008] A partition ring is located on the lower surface of the dielectric filter body and directly below the negative coupling groove. The partition ring includes an inner edge close to the center of the partition ring, an outer edge away from the center of the partition ring, and an end edge connecting the inner edge and the outer edge. The area surrounded by the inner edge, the outer edge and the end edge exposes the dielectric filter body. The negative coupling groove and the partition ring work together to achieve capacitive coupling between the two adjacent dielectric resonators.

[0009] Preferably, the negative coupling groove is a stepped blind groove formed by a shallow blind groove and a deep blind groove intersecting each other, the shallow blind groove has an opening only on the upper surface of the dielectric filter body, the deep blind groove has openings on both the upper surface and the front surface of the dielectric filter body, and the groove depth of the shallow blind groove in the up-down direction is less than the groove depth of the deep blind groove in the up-down direction.

[0010] Preferably, the projection area of ​​the negative coupling groove on the lower surface of the dielectric filter body intersects with the area where the partition ring is located, and the area where the partition ring is located refers to the area surrounded by the inner edge, the outer edge and the end edge.

[0011] Preferably, the area enclosed by the inner edge, the outer edge and the end edge is any one of a C-shape, a U-shape or a polygon with a single opening.

[0012] Further preferably, the area enclosed by the inner edge, the outer edge and the end edge is C-shaped, the inner edge and the outer edge are both circular arcs, and the curvature of the inner edge and / or the outer edge is greater than or equal to 300°.

[0013] Further preferably, the diameter of the circle where the inner edge and / or the outer edge are located is greater than or equal to the slot width of the negative coupling slot in the left-right direction.

[0014] Further preferably, the area enclosed by the inner edge, the outer edge and the end edge is U-shaped, and the partition ring has two transmission sections respectively perpendicular to the front surface of the dielectric filter body and a connecting section connecting the two transmission sections.

[0015] Further preferably, the distance between the two transmission sections is greater than or equal to the slot width of the negative coupling slot in the left-right direction.

[0016] Further preferably, the connecting section is parallel to the front surface of the dielectric filter body.

[0017] To achieve the above object, the technical solution adopted by the present invention also includes a radio transceiver device, wherein the radio transceiver device includes any one of the dielectric filters described above.

[0018] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:

[0019] The dielectric filter provided by the present invention realizes capacitive coupling through the combined action of a negative coupling groove and a partition ring. By arranging the negative coupling groove on the upper surface of the dielectric filter body, the negative coupling groove has openings on both the upper surface and the front surface of the dielectric filter body. When the ceramic material is sintered at a high temperature, the shape and precision of the negative coupling groove change little, and the influence on the electrical performance of the dielectric filter is small. By arranging the partition ring on the lower surface of the dielectric filter body and making the partition ring directly below the negative coupling groove, the partition ring can compensate for the influence of the shape and precision change of the negative coupling groove on the electrical performance of the dielectric filter, so that the electrical performance of the dielectric filter is more stable and the yield rate is high. In addition, due to the existence of the partition ring, the depth of the negative coupling groove does not need to be too deep, so that the volume of the negative coupling groove accounts for a small proportion in the entire dielectric filter, and the structural strength of the dielectric filter is better. The present invention also provides a radio transceiver including the above-mentioned dielectric filter. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 It is a three-dimensional perspective schematic diagram of a dielectric filter embodiment 1 of the present invention.

[0022] Figure 2 for Figure 1 Schematic top view of .

[0023] Figure 3 for Figure 1 Schematic diagram of the top view.

[0024] Figure 4 for Figure 2 Cross-sectional view along the AA direction.

[0025] Figure 5 for Figure 4 A partial enlarged view of point B in the middle.

[0026] Figure 6 It is a perspective schematic diagram of a dielectric filter embodiment 2 of the present invention.

[0027] Figure 7 It is a three-dimensional perspective schematic diagram of Example 3 of the dielectric filter in the present invention.

[0028] Figure 8 It is a three-dimensional perspective schematic diagram of Example 4 of the dielectric filter in the present invention.

[0029] Fig. 9 This is a diagram of the electrical performance of dielectric filter embodiment 1 of the present invention.

[0030] Wherein: 100. dielectric filter; 101. dielectric filter body; 200. first dielectric resonator; 201. first dielectric resonator body; 202. first debugging hole; 300. second dielectric resonator; 301. second dielectric resonator body; 302. second debugging hole; 400. negative coupling slot; 401. deep blind slot; 402. shallow blind slot; 500. conductive layer; 600. partition ring; 601. inner edge; 602. outer edge; 603. end edge; 604. transmission section; 605. connection section; 606. opening. DETAILED DESCRIPTION

[0031] The following will describe the technical solutions in the embodiments of the present invention in detail in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate directions or positional relationships based on the attached Figure 1The orientation or positional relationship shown is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0033] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] Example 1

[0035] like Figure 1-5 As shown, the dielectric filter 100 provided by the present invention includes two dielectric resonators with the same structure, namely a first dielectric resonator 200 and a second dielectric resonator 300. The first dielectric resonator 200 includes a first dielectric resonator body 201 made of a ceramic material and a first debugging hole 202 located on the upper surface of the first dielectric resonator body 201. The first debugging hole 202 is a blind hole and is used to debug the resonant frequency of the first dielectric resonator 200. The second dielectric resonator 300 includes a second dielectric resonator body 301 made of a ceramic material and a second debugging hole 302 located on the upper surface of the second dielectric resonator body 301. The second debugging hole 302 is a blind hole and is used to debug the resonant frequency of the second dielectric resonator 300. The first dielectric resonator body 201 and the second dielectric resonator body 301 constitute a dielectric filter body 101.

[0036] The dielectric filter 100 further includes a negative coupling slot 400, a conductive layer 500, and a partition ring 600, wherein the negative coupling slot 400 is located on the upper surface of the dielectric filter body 101 and is located at the connection position of the first dielectric resonator 200 and the second dielectric resonator 300, and the negative coupling slot 400 is a blind slot, and the negative coupling slot 400 has an opening on the upper surface of the dielectric filter body 101, and the negative coupling slot 400 also extends forward through the front surface of the dielectric filter body 101, so that the negative coupling slot 400 is located on the dielectric filter body The front surface of the dielectric filter body 101 also has an opening; the conductive layer 500 covers the surface of the dielectric filter body 101, the inner wall surface of the first debugging hole 202, the inner wall surface of the second debugging hole 302 and the inner wall surface of the negative coupling groove 400, and the conductive layer 500 is made of silver; the partition ring 600 is located on the lower surface of the dielectric filter body 101 and is located directly below the negative coupling groove 400, and the partition ring 600 includes an inner edge 601 close to the center of the partition ring 600, an outer edge 602 away from the center of the lower surface of the dielectric filter body 101, and a conductive layer 500 is covered on the surface of the dielectric filter body 101, and the conductive layer 500 is made of silver; the partition ring 600 is located on the lower surface of the dielectric filter body 101 and is located directly below the negative coupling groove 400, and the partition ring 600 includes an inner edge 601 close to the center of the partition ring 600, and an outer edge 603 away from the center of the lower surface of the dielectric filter body 101. 02, the end edge 603 connecting the inner edge 601 and the outer edge 602, the partition ring 600 is not covered by the conductive layer 500, the area surrounded by the inner edge 601, the outer edge 602 and the end edge 603 is in a U-shape with an opening, and the dielectric filter body 101 is exposed in the area, and the negative coupling groove 400 and the partition ring 600 are used to realize the capacitive coupling between the first dielectric resonator 200 and the second dielectric resonator 300; the partition ring 600 is in a U-shape, and the partition ring 600 has two sections perpendicular to the dielectric filter and the dielectric filter body 101. The transmission section 604 on the front surface of the main body 101 and the connecting section 605 connecting the two transmission sections 604, the distance between the two transmission sections 604 is greater than the slot width of the negative coupling slot 400 in the left and right directions, the connecting section 605 is parallel to the front surface of the dielectric filter main body 101, the projection area of ​​the negative coupling slot 400 on the lower surface of the dielectric filter main body 101 intersects with the area where the partition ring 600 is located, and the area where the partition ring 600 is located refers to the area surrounded by the inner edge 601, the outer edge 602 and the end edge 603.

[0037] like Fig. 9As shown, the capacitive coupling between the first dielectric resonator 200 and the second dielectric resonator 300 is achieved by the negative coupling slot 400 and the isolating ring 600 to generate the low-end transmission zero point A; the strength of the transmission zero point A can be adjusted by adjusting the size of the negative coupling slot 400, and the strength of the transmission zero point A can also be adjusted by adjusting the shape, size and position of the isolating ring 600 without changing the negative coupling slot 400; the deeper the slot depth of the negative coupling slot 400, the stronger the transmission zero point A; the longer the length of the negative coupling slot 400 in the front-to-back direction, the stronger the transmission zero point A; the wider the slot width of the negative coupling slot 400 in the left-to-right direction, the stronger the transmission zero point A; the longer the transmission segment 604 of the isolating ring 600, the stronger the transmission zero point A; the larger the distance between the inner edge 601 and the outer edge 602 of the isolating ring 600, the weaker the transmission zero point A; the larger the distance between the two transmission segments 604 of the isolating ring 600, the stronger the transmission zero point A.

[0038] Example 2

[0039] like Figure 6 As shown, Example 2 is basically the same as Example 1, except that the partition ring 600 in Example 2 is a circular ring with an opening 606, so that the partition ring 600 is C-shaped, the opening 606 faces the rear surface of the dielectric filter body 101, the inner edge 601 and the outer edge 602 are both arcs, the curvature of the inner edge 601 and the outer edge 602 are both greater than 300°, and the diameter of the circle where the inner edge 601 and the outer edge 602 are located is greater than the slot width of the negative coupling slot 400 in the left and right directions.

[0040] Example 3

[0041] like Figure 7 As shown, the third embodiment is substantially the same as the second embodiment, except that the opening 606 of the partition ring 600 in the third embodiment faces the front surface of the dielectric filter body 101 .

[0042] Example 4

[0043] like Figure 8 As shown, Example 4 is basically the same as Example 2, except that the negative coupling slot 400 in Example 4 is a step-shaped blind slot formed by a shallow blind slot 402 and a deep blind slot 401 intersecting each other, the shallow blind slot 402 has an opening only on the upper surface of the dielectric filter body 101, the deep blind slot 401 has openings on both the upper surface and the front surface of the dielectric filter body 101, and the slot depth of the shallow blind slot 402 in the up-down direction is less than the slot depth of the deep blind slot 401 in the up-down direction.

[0044] The dielectric filter provided by the present invention realizes capacitive coupling through the combined action of a negative coupling groove and a partition ring. By arranging the negative coupling groove on the upper surface of the dielectric filter body, the negative coupling groove has openings on both the upper surface and the front surface of the dielectric filter body. When the ceramic material is sintered at a high temperature, the shape and precision of the negative coupling groove change little, and the influence on the electrical performance of the dielectric filter is small. By arranging the partition ring on the lower surface of the dielectric filter body and making the partition ring directly below the negative coupling groove, the partition ring can compensate for the influence of the shape and precision change of the negative coupling groove on the electrical performance of the dielectric filter, so that the electrical performance of the dielectric filter is more stable and the yield rate is high. In addition, due to the existence of the partition ring, the depth of the negative coupling groove does not need to be too deep, so that the volume of the negative coupling groove accounts for a small proportion in the entire dielectric filter, and the structural strength of the dielectric filter is better.

[0045] The present invention further provides a radio transceiver device, which includes any one of the dielectric filters in the above embodiments. The dielectric filter in the radio transceiver device can be used to filter radio frequency signals.

[0046] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0047] The above is only a specific implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A dielectric filter, comprising at least two dielectric resonators, wherein the dielectric resonator comprises a dielectric resonator body made of ceramic material and a debugging hole located on the upper surface of the dielectric resonator body, wherein the debugging hole is a blind hole and is used to debug the resonant frequency of the dielectric resonator in which the debugging hole is located; all the dielectric resonator bodies constitute a dielectric filter body, and the dielectric filter further comprises: A negative coupling slot, which is located on the upper surface of the dielectric filter body and at the connection position of two adjacent dielectric resonators, and is a blind slot, and has an opening on the upper surface of the dielectric filter body; A conductive layer covering the surface of the dielectric filter body, the inner wall surface of the debugging hole and the inner wall surface of the negative coupling groove; Features: The negative coupling slot also has an opening on the front surface of the dielectric filter body; The dielectric filter also includes a non-closed isolating ring, which is located on the lower surface of the dielectric filter body and directly below the negative coupling groove. The isolating ring includes an inner edge close to the center of the isolating ring, an outer edge away from the center of the isolating ring, and an end edge connecting the inner edge and the outer edge. The area surrounded by the inner edge, the outer edge and the end edge exposes the dielectric filter body. The area surrounded by the inner edge, the outer edge and the end edge is any one of a C-shape, a U-shape or a polygon with a single opening. The projection area of ​​the negative coupling groove on the lower surface of the dielectric filter body intersects with the area where the isolating ring is located. The area where the isolating ring is located refers to the area surrounded by the inner edge, the outer edge and the end edge. The negative coupling groove and the isolating ring work together to realize capacitive coupling between the two adjacent dielectric resonators.

2. The dielectric filter according to claim 1, characterized in that: The negative coupling groove is a stepped blind groove formed by the interpenetration of a shallow blind groove and a deep blind groove, wherein the shallow blind groove has an opening only on the upper surface of the dielectric filter body, and the deep blind groove has openings on both the upper surface and the front surface of the dielectric filter body, and the groove depth of the shallow blind groove in the up-down direction is less than the groove depth of the deep blind groove in the up-down direction.

3. The dielectric filter according to claim 1, characterized in that The area enclosed by the inner edge, the outer edge and the end edge is C-shaped, the inner edge and the outer edge are both circular arcs, and the curvature of the inner edge and / or the outer edge is greater than or equal to 300°.

4. The dielectric filter according to claim 3, characterized in that The diameter of the circle where the inner edge and / or the outer edge are located is greater than or equal to the slot width of the negative coupling slot in the left-right direction.

5. The dielectric filter according to claim 1, characterized in that: The area surrounded by the inner edge, the outer edge and the end edge is U-shaped, and the partition ring has two transmission sections respectively perpendicular to the front surface of the dielectric filter body and a connecting section connecting the two transmission sections.

6. The dielectric filter according to claim 5, characterized in that The distance between the two transmission sections is greater than or equal to the slot width of the negative coupling slot in the left-right direction.

7. The dielectric filter according to claim 5, characterized in that The connecting section is parallel to the front surface of the dielectric filter body.

8. Radio transceiver equipment, characterized in that The radio transceiver device comprises the dielectric filter according to any one of claims 1 to 7.

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