A miniaturized stripline dielectric substrate integrated filter

Abstract

The application provides a miniaturized strip dielectric substrate integrated filter and belongs to the technical field of microwave communication. The application discloses a miniaturized strip dielectric substrate integrated filter, which comprises a high dielectric constant dielectric substrate, a low dielectric constant dielectric substrate group and a metal ground layer which are arranged in layers from inside to outside on the upper and lower surfaces of the high dielectric constant dielectric substrate; the high dielectric constant dielectric substrate comprises a strip dielectric block, four metal through holes which are evenly arranged along the transverse center line direction of the strip dielectric block, fixed strips which are symmetrically arranged at the longitudinal two ends of the strip dielectric block, and connecting strips which are arranged between the end of the strip dielectric block and the corresponding fixed strips. The application has the beneficial effects that: the miniaturized strip dielectric substrate integrated filter provided by the application loads four metalized through holes in the middle of the strip dielectric block, forms two integrated resonators which are simultaneously resonated in half-mode TE y111 modules, realizes high integration degree and miniaturization, low conductor loss and reasonable layout.

Description

Technical Field

[0001] This invention relates to the field of microwave communication technology, and in particular to a miniaturized strip dielectric substrate integrated filter. Background Technology

[0002] With the rapid development of wireless communication, the miniaturization requirements of microwave RF circuits are becoming increasingly stringent. Filtering circuits are a fundamental and crucial technology in signal processing, used to isolate or filter out certain frequencies within a specific frequency band or range, improving the frequency selectivity of the system. Therefore, they are widely used in wireless communication technology. Simultaneously, replacing some or all of the metal in traditional microwave structures with dielectric materials reduces conductor losses, and achieving planarization through multilayer dielectric structures not only reduces system power consumption but also facilitates integration or self-packaging to meet the demands of integrated development. Therefore, dielectric resonators, due to their advantages such as high Q-value, high temperature stability, and high power capacity, have become a research hotspot in recent years. Thus, proposing a miniaturized dielectric resonator filter has significant research value and importance.

[0003] Most miniaturized dielectric resonator filters reported to date are based on dielectric ceramics combined with metal, which are difficult to package and integrate. Existing dielectric substrate integrated filters are mainly achieved through the mutual coupling between two resonators, resulting in relatively large dimensions.

[0004] How to solve the above-mentioned technical problems is the challenge facing this invention. Summary of the Invention

[0005] The purpose of this invention is to provide a miniaturized strip dielectric substrate integrated filter with high integration, low conductor loss, and reasonable layout.

[0006] To achieve the above-mentioned objectives, the present invention adopts the following technical solution: a miniaturized strip dielectric substrate integrated filter, characterized in that it includes a high dielectric constant dielectric substrate, and a low dielectric constant dielectric substrate group and a metal ground layer respectively stacked from the inside to the outside on the upper and lower surfaces of the high dielectric constant dielectric substrate.

[0007] The high dielectric constant dielectric substrate includes a strip-shaped dielectric block, four metal through holes uniformly opened along the transverse centerline of the strip-shaped dielectric block, two fixed strips symmetrically located at both ends of the longitudinal direction of the strip-shaped dielectric block, and a connecting strip disposed between the end of the strip-shaped dielectric block and the corresponding fixed strip.

[0008] The low dielectric constant dielectric substrate group includes a first low dielectric constant dielectric substrate located on the outer layer and a second low dielectric constant dielectric substrate located on the inner layer with etched air grooves, wherein the orthographic projection of the strip dielectric block along the vertical direction is located within the air grooves;

[0009] Two feed lines are provided on one of the second low dielectric constant dielectric substrates. The two feed lines are symmetrically located on both sides of the four metal vias. The feed lines extend from the corresponding edge of the second low dielectric constant dielectric substrate to the strip dielectric block.

[0010] Furthermore, the air slot of one of the second low dielectric constant dielectric substrates is configured as a rectangular air slot, and the air slot of the other second low dielectric constant dielectric substrate is configured as an E-shaped air slot. The two feed lines correspond one-to-one with the two concave parts of the E-shaped air slot. This not only facilitates the layout of the feed lines, but also reduces dielectric loss and improves the Q value of the resonator.

[0011] Furthermore, the feed line is disposed in the recess of the E-shaped air groove, close to the surface of the high dielectric constant substrate.

[0012] Furthermore, the orthographic projection of the E-shaped air trough along the vertical direction lies within the rectangular air trough.

[0013] Furthermore, the second low-dielectric-constant dielectric substrate with the rectangular air groove is located above the high-dielectric-constant dielectric substrate.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0015] 1. By creating four metallized vias on the strip dielectric block, two simultaneous resonant modes TE are formed. y111 A high-Q strip dielectric substrate integrated resonator with modularity and packageability was developed, realizing a strip dielectric integrated resonator filter with high integration and miniaturization.

[0016] 2. Four uniformly distributed metallized vias are loaded in the center of the strip dielectric block. On the one hand, a single resonator can be divided into two half-mode resonators to achieve miniaturization. On the other hand, coupling between the two half-mode resonators can be achieved, making it easier to adjust the coupling coefficient.

[0017] 3. Etching E-shaped air grooves on a low dielectric constant substrate can facilitate the layout of the feed lines and reduce dielectric losses, thereby improving the Q value of the resonator. Attached Figure Description

[0018] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0019] Figure 1 This is a cross-sectional structural diagram of the present invention;

[0020] Figure 2This is an exploded view of the present invention;

[0021] Figure 3 This is a top view of the high dielectric constant substrate in this invention;

[0022] Figure 4 This is a top view of the E-groove low dielectric constant dielectric substrate in this invention;

[0023] Figure 5 This is a top view of the rectangular groove low dielectric constant dielectric substrate of the present invention;

[0024] Figure 6 This is a schematic diagram showing the positional relationship between the high dielectric constant dielectric substrate, the rectangular groove low dielectric constant dielectric substrate, and the E-shaped groove low dielectric constant dielectric substrate in this invention.

[0025] Figure 7 The image shows a simulation diagram of the frequency response of the filter in the embodiment.

[0026] The reference numerals in the attached figures are as follows: 1. Metal ground; 2. First low dielectric constant dielectric substrate; 3. Rectangular groove low dielectric constant dielectric substrate; 31. Rectangular air groove; 4. High dielectric constant dielectric substrate; 41. Strip dielectric block; 42. Connecting strip; 43. Fixing strip; 44. Metal through-hole; 5. E-shaped groove low dielectric constant dielectric substrate; 51. E-shaped air groove; 52. Feed line. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. Of course, the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0028] Example 1

[0029] The present invention provides the following technical solution: a miniaturized strip dielectric substrate integrated filter, comprising a high dielectric constant dielectric substrate 4, and a low dielectric constant dielectric substrate group and a metal ground layer respectively stacked from the inside to the outside on the upper and lower surfaces of the high dielectric constant dielectric substrate;

[0030] See appendix Figure 3 The high dielectric constant dielectric substrate 4 includes a strip dielectric block 41, four metal through holes 44 uniformly opened along the transverse center line of the strip dielectric block 41, two fixed strips 43 symmetrically located at both ends of the longitudinal direction of the strip dielectric block 41, and a connecting strip 42 disposed between the end of the strip dielectric block 41 and the corresponding fixed strip 43.

[0031] The low dielectric constant dielectric substrate group includes a first low dielectric constant dielectric substrate 2 located on the outer layer and a second low dielectric constant dielectric substrate located on the inner layer with etched air grooves. The vertical projection of the strip dielectric block 41 is located in the air groove.

[0032] Two feed lines 52 are provided on one of the second low dielectric constant dielectric substrates. The two feed lines 52 are symmetrically located on both sides of the four metal vias 44. The feed lines 52 extend from the corresponding edge of the second low dielectric constant dielectric substrate to the strip dielectric block 41.

[0033] Each of the four metal vias 44 forms a cavity-type strip dielectric resonator on both sides, and the four metal vias 44 form a coupling window, thus forming two resonators simultaneously in half-mode TE. y111 This high-Q strip dielectric substrate integrated resonator, which is modular and packageable, utilizes four metal vias 44 on the main strip dielectric block 41 of the high dielectric constant substrate 4 to separate a half-wavelength mode into two quarter-wavelength modes that are coupled together. This successfully transforms the structure of two coupled resonators into a single resonator, realizing a strip dielectric integrated resonator filter with high integration and miniaturization. In use, a signal is input from one of the feed lines 52, exciting the resonant mode of the corresponding cavity-type strip dielectric resonator. The signal is then coupled to another cavity-type strip dielectric resonator through a coupling window and output through another feed line 52. Therefore, the strip dielectric integrated filter constructed from this resonator exhibits miniaturization, and its main structure, being a strip dielectric integrated structure, has lower conductor losses compared to integrable metal resonators.

[0034] Example 2

[0035] See appendix Figure 1 , 2 4, 5, and 6 are based on Embodiment 1, and are otherwise the same as Embodiment 1. The difference from Embodiment 1 is that the air slot of one of the second low dielectric constant dielectric substrates is set as a rectangular air slot 31, and the second low dielectric constant dielectric substrate is denoted as rectangular slot low dielectric constant dielectric substrate 3. The air slot of the other second low dielectric constant dielectric substrate is set as an E-shaped air slot 51, and the second low dielectric constant dielectric substrate is denoted as E-shaped slot low dielectric constant dielectric substrate 5. The two feed lines 52 correspond one-to-one with the two concave parts of the E-shaped air slot 51. On the one hand, this can facilitate the layout of the feed lines, and on the other hand, it can reduce dielectric loss and improve the Q value of the resonator.

[0036] The feed line 52 is disposed in the recess of the E-shaped air groove 51, close to the surface of the high dielectric constant substrate 4.

[0037] Example 3

[0038] See appendix Figure 1 ,2 Based on Embodiment 2, everything else is the same as in Embodiment 2. The difference is that the orthographic projection of the E-shaped air groove 51 along the vertical direction is located inside the rectangular air groove 31; the second low dielectric constant dielectric substrate with the rectangular air groove 31 is located above the high dielectric constant dielectric substrate 4.

[0039] Appendix Figure 7 This is a simulation diagram of the frequency response of the miniaturized strip dielectric substrate integrated filter corresponding to Example 3. The physical dimensions of the filter in this case are 40mm × 40mm × 5.414mm. The first low-dielectric-constant dielectric substrate 2 and the second low-dielectric-constant dielectric substrate are both RO4003C substrates with a dielectric constant of 3.55, a loss angle of 0.0027, and thicknesses of 0.203mm and 0.913mm, respectively. The high-dielectric-constant dielectric substrate 4 is an RO3010 substrate with a dielectric constant of 10.2, a loss angle of 0.0023, and a thickness of 3.148mm. The center frequency is set to 11.35GHz, and the zero point on the right side of the passband is located at 11.5GHz. Its 3-dB relative bandwidth is 0.62%, and the minimum insertion loss is only 1.9dB.

[0040] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A miniaturized strip dielectric substrate integrated filter, characterized in that, It includes a high dielectric constant dielectric substrate (4), and a low dielectric constant dielectric substrate group and a metal ground are respectively stacked from the inside to the outside on both the upper and lower surfaces of the high dielectric constant dielectric substrate (4); The high dielectric constant substrate (4) includes a strip dielectric block (41), four metal through holes (44) uniformly opened along the transverse center line of the strip dielectric block (41), two fixed strips (43) symmetrically located at both ends of the longitudinal direction of the strip dielectric block (41), and a connecting strip (42) disposed between the end of the strip dielectric block (41) and the corresponding fixed strip (43). The low dielectric constant dielectric substrate group includes a first low dielectric constant dielectric substrate (2) located on the outer layer and a second low dielectric constant dielectric substrate located on the inner layer with etched air grooves. The orthographic projection of the strip dielectric block (41) along the vertical direction is located in the air groove. Two feed lines (52) are provided on the second low dielectric constant dielectric substrate located below the high dielectric constant dielectric substrate (4). The two feed lines (52) are symmetrically located on both sides of the four metal vias (44). The feed lines (52) extend from the corresponding edge of the second low dielectric constant dielectric substrate to the strip dielectric block (41). The air slot of the second low dielectric constant dielectric substrate located above the high dielectric constant dielectric substrate (4) is configured as a rectangular air slot (31), and the air slot of the second low dielectric constant dielectric substrate located below the high dielectric constant dielectric substrate (4) is configured as an E-shaped air slot (51). The two feed lines (52) correspond one-to-one with the two concave parts of the E-shaped air slot (51).

2. The miniaturized strip dielectric substrate integrated filter according to claim 1, characterized in that, The feed line (52) is disposed in the recess of the E-shaped air groove (51) on the surface of the high dielectric constant substrate (4).

3. The miniaturized strip dielectric substrate integrated filter according to claim 1, characterized in that, The orthographic projection of the E-shaped air trough (51) along the vertical direction is located within the rectangular air trough (31).

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