CN212257633U

CN212257633U - Half-mode substrate integrated waveguide dual-band filter

Info

Publication number: CN212257633U
Application number: CN202020757572.5U
Authority: CN
Inventors: 张中华; 夏铭; 熊荆
Original assignee: CHONGQING VOCATIONAL INSTITUTE OF SAFETY & TECHNOLOGY
Current assignee: CHONGQING VOCATIONAL INSTITUTE OF SAFETY & TECHNOLOGY
Priority date: 2020-05-10
Filing date: 2020-05-10
Publication date: 2020-12-29
Anticipated expiration: 2030-05-10

Abstract

The utility model discloses a half mode substrate integrated waveguide double-band filter of complementary opening resonance ring and U groove structure. The key points are as follows: the double-band filter comprises a dielectric substrate, wherein a top metal layer, a bottom grounding metal layer and an open-circuit branch structure are arranged on the dielectric substrate, the top metal layer is used for etching a complementary open resonant ring, a U groove and a capacitor resonator structure, the bottom grounding metal patch is used for etching the complementary open resonant ring and the U groove to form a defected ground structure, the defected ground structure and the center of the open-circuit branch are positioned in a straight line, the top metal patch penetrates through the dielectric substrate through a row of metalized through holes to be connected with the bottom grounding metal patch, and a gradual impedance matching unit inputs and outputs a micro-strip feeder line. The novel passband is generated by a complementary split resonant ring and a U-shaped groove structure, the 3dB bandwidth is enhanced by introducing a capacitive resonator structure, the passband is generated by utilizing the transmission characteristics and the coupling of an open-circuit branch line and a defected ground structure, the two passbands are mutually independent, and the two passbands are cascaded to enhance the selectivity of the passband.

Description

Half-mode substrate integrated waveguide dual-band filter

Technical Field

The utility model relates to an use the filtering at wireless communication system, especially relate to a half mode substrate integrated waveguide double band filter of complementary opening resonance ring and U groove structure.

Background

With the 5G era, communication devices are continuously climbing, limited frequency domain resources are seriously impacted, and communication systems of various frequency bands are in succession. The role of a high quality filter is particularly important in order to be relatively independent for each frequency band.

The half-mode substrate integrated waveguide has the advantages of high performance, high Q value, low loss, low cost and easy integration; the defect ground structure changes the distributed inductance and the distributed capacitance of the transmission line, and obtains the band stop characteristic, the slow wave characteristic and the like, the slow wave characteristic can be used for realizing the miniaturization design of the filter, and the band stop characteristic can be used for realizing the design of the stop band filter. Therefore, the dual-band filter is designed by utilizing the half-mode substrate integrated waveguide and the defected ground technology, and the advantages of low loss, low cost, easy integration and the like of the filter are realized.

Disclosure of Invention

The utility model discloses a main objective adopts half mode substrate integrated waveguide and defect ground technique, combines complementary opening resonance ring, U groove defect ground structure and electric capacity resonance structure's transmission characteristic, provides a high selectivity, low-loss double-band filter.

The purpose of the utility model is realized through the following technical scheme:

a half-mode substrate integrated waveguide dual-band filter comprising: a top layer, a dielectric substrate layer and a bottom layer of a metal.

The top layer is provided with a metal plane 1 and an open-circuit branch line 9, the metal plane 1 etches a complementary open-circuit resonant ring 2, a U-shaped groove structure 3, an inverted U-shaped groove structure 4 and a capacitor resonant structure 5; the capacitor resonance structure 5 is positioned inside the complementary open resonance ring 2, the U-shaped groove structure 3 and the inverted U-shaped groove structure 4 are axisymmetric structures, and the complementary open resonance ring 2 is positioned in a structure formed by the U-shaped groove structure 3 and the inverted U-shaped groove structure 4.

The metal plane 1 penetrates through the medium substrate layer through a row of metallized through holes 11 to be connected with a bottom layer grounding metal ground, and the microstrip feed line is connected with the metal plane 1 through a metal gradient 10.

And the bottom layer metal ground etches a complementary opening resonant ring defect ground 6, a U-groove defect ground structure 7 and an inverted U-groove defect ground structure 8. The U-groove defected ground structure 7 and the inverted U-groove defected ground structure 8 are axisymmetric structures, and the complementary split resonant ring defected ground 6 is positioned in the structure formed by the U-groove defected ground structure 7 and the inverted U-groove defected ground structure 8.

The metal plane 1 is etched with the complementary opening resonance ring 2 comprising a gap 2-1 and a gap 2-2, and the opening directions of the gaps are opposite; the metal plane 1 etches a U-shaped groove structure 3 and an inverted U-shaped groove structure 4, the directions of the U-shaped grooves are opposite, and the U-shaped grooves are used for realizing a filter passband; the etched capacitor resonance structure 5 of the metal plane 1 comprises a gap 5-1 and a metalized through hole 5-2, wherein the metalized through hole 5-2 penetrates through a medium substrate layer to be connected with a bottom layer grounding metal ground, and is used for generating resonance frequency points and increasing the 3dB bandwidth.

The bottom layer metal ground etching complementary opening resonant ring defect ground 6 comprises a gap 6-1 and a gap 6-2, and the gap opening directions are opposite; the bottom layer metal ground etches the U-groove defected ground structure 7 and the inverted U-groove 8, and the opening directions of the U-groove defected ground structure are opposite; the sizes of the defected ground structure and the open branch line 9 structure and the coupling control resonance frequency point and the passband bandwidth.

The key technical difficulty of the half-mode substrate integrated waveguide double-band filter is to solve the size and coupling of a complementary split resonant ring, a U-groove structure, an inverted U-groove structure and a capacitance resonant structure and the size and coupling of a defected ground structure and an open branch line and determine key structural parameters influencing double-band transmission response. The main structure of the cascade filter improves the selectivity of the double-band filter.

Compared with the prior art, the utility model, following advantage and beneficial effect have:

1. the utility model discloses utilize half mode substrate integrated waveguide and defect ground technique for design flexibility, easy integration, small-size, low loss.

2. The utility model utilizes the complementary open resonant ring, the U-shaped groove structure, the capacitor resonant structure and the defected ground structure, so that the structure is easy to realize and simple; the two pass bands are respectively controlled by different resonance structures, and the mutual interference between the two pass bands is small.

Drawings

Fig. 1 is a schematic diagram of a half-mode substrate integrated waveguide dual-band filter according to the present invention;

FIG. 2 is a schematic diagram of a top complementary split-gate resonant and U-slot structure of the dielectric substrate shown in FIG. 1;

FIG. 3 is a schematic diagram of a top layer capacitive resonance structure of the dielectric substrate shown in FIG. 1;

FIG. 4 is a schematic view of a defective structure of the bottom layer of the dielectric substrate shown in FIG. 1;

fig. 5 is a frequency response graph of an example of a half-mode substrate integrated waveguide dual-band filter according to the present invention.

Detailed Description

The present invention will be described in further detail with reference to examples and drawings, but the embodiments of the present invention are not limited thereto.

As shown in fig. 1 to 5, in a half-mode substrate integrated waveguide dual-band filter, the length and width of a slot 2-1 etched in a complementary open resonant ring 2 of a metal plane 1 are respectively 21.5mm and 0.5mm, the length and width of the slot 2-2 are respectively 13.6mm and 0.5mm, and the metal distance between the slot 2-1 and the slot 2-2 is 0.5 mm; the length and the width of the etched U-shaped groove structure 3 are respectively 13.5mm and 0.6mm, the distance between the U-shaped groove 3 and the inverted U-shaped groove 4 is 0.3mm, the metal distance between the gap 2-1 and the U-shaped groove 3 is 0.3mm, the distance between the U-shaped groove 3 and the left edge is 0.3mm, the distance between the upper edge and the right edge is 0.2mm, and the distance between the left U-shaped groove and the right U-shaped groove is 5 mm; the diameters of the inner circle and the outer circle in the gap 5-1 of the etched capacitor resonance structure 5 are 0.6mm and 0.8mm respectively, and the diameter of the metalized through hole 5-2 is 0.6 mm.

The diameter of the metallized through hole 11 is 0.5mm, the distance between the centers of circles is 0.9mm, and the distance between the center of circle and the U groove 3 is 0.4 mm.

The length and the width of a gap 6-1 in the bottom metal etching complementary opening resonant ring defect ground 6 are respectively 14.6mm and 0.3mm, the length and the width of a gap 6-2 are respectively 10.6mm and 0.3mm, and the metal distance between the gap 6-1 and the gap 6-2 is 0.2 mm; the length and the width of the etched U-shaped groove structure 7 are respectively 9mm and 0.3mm, the distance between the U-shaped groove 7 and the inverted U-shaped groove 8 is 0.4mm, the metal distance between the gap 6-1 and the U-shaped groove 7 is 0.2mm, the length and the width of the open-circuit branch line 9 are respectively 5.5mm and 1mm, and the distance between the centers of the left open-circuit branch line and the right open-circuit branch line is 10.3 mm.

In this example, Rogers 4003 was used as the dielectric substrate, which had a dielectric constant of 3.55 and a thickness of 0.508 mm.

Fig. 4 is a graph showing the frequency response of this example. In the drawingsComprising two large curves S₂₁︱、︱S₁₁An | S₂₁An | being a transmission characteristic curve, a curve S of a signal₁₁The | is the reflection characteristic curve of the port. As can be seen from the figure, the filter has dual-band passband response, wherein the center frequency of one passband is 2.1GHz, the minimum insertion loss in the passband is 1.1dB, the return loss is more than 23dB, and the 3dB bandwidth of the passband is 9.52%; the center frequency of the second pass band is 3.2GHz, the minimum insertion loss in the pass band is 0.8dB, the return loss in the pass band is more than 20dB, and the 3dB broadband of the pass band is 12.5%; the first and second passbands have a bandwidth ratio of about 1: 1; the transmission zero points are respectively positioned at 2.45GHz and 3.9GHz, and the attenuation of the corresponding transmission characteristics is 41dB and 33 dB.

Compared with the prior art, the utility model relates to a half mode substrate integrated waveguide double-band filter. The transmission characteristics and the coupling of the half-mode substrate integrated waveguide and the defect ground are utilized to generate dual-passband frequency response, and the selectivity of a passband is improved by adopting cascade mutual coupling.

The embodiments of the present invention are not limited by the above embodiments, and any other equivalent substitutions or changes without departing from the spirit and principles of the present invention are included in the protection scope of the present invention.

Claims

1. A half-mode substrate integrated waveguide dual-band filter is characterized in that: the double-band filter comprises a top layer, a medium substrate layer and a bottom layer metal ground three-layer structure;

the top layer is provided with a metal plane (1) and an open-circuit branch line (9), the metal plane (1) etches the complementary open-circuit resonant ring (2), the U-shaped groove structure (3), the inverted U-shaped groove structure (4) and the capacitor resonant structure (5); the capacitance resonance structure (5) is positioned inside the complementary opening resonance ring (2), the U-shaped groove structure (3) and the inverted U-shaped groove structure (4) are in axial symmetry, and the complementary opening resonance ring (2) is positioned in a structure formed by the U-shaped groove structure (3) and the inverted U-shaped groove structure (4);

the metal plane (1) penetrates through the medium substrate layer through a row of metalized through holes (11) to be connected with the bottom layer grounding metal ground, and the microstrip feed line is connected with the metal plane (1) through a metal gradient (10);

the bottom layer metal ground is etched to complement the opening resonance ring defect ground (6), the U-groove defect ground structure (7) and the inverted U-groove defect ground structure (8); the U-groove defected ground structure (7) and the inverted U-groove defected ground structure (8) are axisymmetric structures, and the complementary split resonant ring defected ground (6) is positioned in the structure formed by the U-groove defected ground structure (7) and the inverted U-groove defected ground structure (8).

2. The half-mode substrate integrated waveguide dual-band filter according to claim 1, wherein: complementary open-ended resonant ring (2), U groove structure (3), inverted U groove structure (4), capacitance resonance structure (5), complementary open-ended resonant ring defect ground (6), U groove defect ground structure (7), inverted U groove defect ground structure (8), branch line of opening a way (9) constitute the major structure of filter, complementary open-ended resonant ring defect ground (6) and the central line of branch line of opening a way (9) are on a straight line.

3. The half-mode substrate integrated waveguide dual-band filter according to claim 1, wherein: a capacitance resonance structure (5) is etched in the complementary open resonance ring (2), and the metalized through hole (5-2) penetrates through the medium substrate layer to be connected with the bottom layer grounding metal ground; and a capacitance resonance structure (5) is utilized to generate resonance frequency points, so that the 3dB bandwidth is increased.

4. The half-mode substrate integrated waveguide dual-band filter according to claim 2, wherein: the main structure is cascaded with two filters to form a double-band filter, so that the selectivity of the filter is improved.