CN116190955A

CN116190955A - Novel air strip line

Info

Publication number: CN116190955A
Application number: CN202211552951.0A
Authority: CN
Inventors: 王洪李; 荆晓超; 王佳欣
Original assignee: 724 Research Institute Of China Shipbuilding Corp
Current assignee: 724 Research Institute Of China Shipbuilding Corp
Priority date: 2022-12-06
Filing date: 2022-12-06
Publication date: 2023-05-30

Abstract

The invention provides a novel air strip line. The air strip line is formed by mixing and pressing five layers of dielectric plates, wherein the central conductor of the air strip line is formed by rectangular metal transmission lines with the same width on two sides of the middle dielectric layer, the rectangular metal transmission lines on two sides of the dielectric layer are connected together through a buried hole, meanwhile, the dielectric layers above and below the central conductor are dug out to form two rectangular cavities, and then the metal layers on two sides of the first dielectric layer and the metal layers on two sides of the fifth dielectric layer are respectively used as an upper grounding plate and a lower grounding plate, so that the central conductor of the air strip line is completely in an air filling state, and extremely low insertion loss is obtained. The air strip line based on the multilayer mixed pressure plate has the advantages of low insertion loss, simple structure and easy integration.

Description

Novel air strip line

Technical Field

The present invention belongs to microwave transmission line technology.

Background

A strip line is a type of transmission line of a half-open structure, for which it is always desired in practice to further reduce its transmission loss, and thus an air panel line structure commonly used in engineering has emerged. The air plate wire structure has the advantages of small insertion loss, high power resistance, large volume and heavy weight, and has higher processing precision and assembly requirements on the structure under the condition of higher working frequency. In the document 'an x-band low sidelobe array antenna with air coaxial feed', song Changhong proposes an air coaxial, inner and outer conductors are of square structures, the terminal of the inner conductor is in a short circuit feed mode, self-supporting and lower transmission loss of the inner conductor are realized, and the transmission line is special in form and is suitable for feeding.

In recent years, a copper-based air micro-coaxial technology has appeared, and the copper-based air micro-coaxial transmission line is composed of a suspended central inner conductor, a grounding outer conductor surrounding the suspended central inner conductor and a periodic medium supporting structure, and has the characteristics of wide frequency band, high isolation, low loss, high power capacity and the like. The transmission line realized by the process has wide working frequency, small insertion loss and high power resistance, but the process is complex. In addition, the low-loss strip line can be realized based on the LTCC technology, and the air strip line realized by the technology has the advantages of wide working frequency, small insertion loss and high power resistance.

Disclosure of Invention

Aiming at the problems of special application scene, complex structure, heavy weight or insufficient method bias theory in engineering practice in the prior art, the invention provides a novel air strip line, which realizes low-loss air filling by utilizing a multi-layer mixed pressing plate.

In order to achieve the technical purpose, the technical scheme of the invention comprises the following steps:

the method sequentially comprises the following steps from top to bottom: the first metal layer, the first dielectric layer and the second metal layer; a third metal layer, a second dielectric layer and a fourth metal layer; a fifth metal layer, a third dielectric layer, and a sixth metal layer; a seventh metal layer, a fourth dielectric layer and an eighth metal layer; a ninth metal layer, a fifth dielectric layer, a tenth metal layer;

all the metal layers and the dielectric layers are symmetrically distributed about the third dielectric layer;

and the metal buried via hole comprises a first metal layer, a second metal layer, a third metal layer, a fourth metal layer, a fifth metal layer, a sixth metal layer and a fifth metal layer.

Further, the center conductor of the air strip line comprises rectangular metal transmission lines with the same width of the fifth metal layer and the sixth metal layer, the fifth metal layer and the rectangular metal transmission lines of the sixth metal layer are connected through metallized buried holes with the distance of 1mm from the fifth layer to the sixth layer, and the metallized buried holes are uniformly distributed along the transmission lines from the initial end of the rectangular metal transmission lines. The metallized buried vias are preferably 0.2mm in diameter.

Further, the second dielectric layer and the fourth dielectric layer above and below the center conductor of the air strip line are hollowed out in the direction along the center conductor to form a rectangular cavity having a width twice the distance between the two ground plates of the air strip line.

Further, the upper ground plate of the air strip line outer conductor is composed of a first metal layer and a second metal layer, and the lower ground plate is composed of a ninth metal layer and a tenth metal layer.

The metallized through holes are uniformly arranged along the two sides of the central conductor and play roles of grounding and shielding.

The air strip line has the advantages of small insertion loss, simple structure and easy integration.

Drawings

FIG. 1 is a schematic cross-sectional view of an air strip line in accordance with an embodiment of the present invention;

FIG. 2 is a schematic cross-sectional dimension of an air strip line according to an embodiment of the present invention;

FIG. 3 is a schematic cross-sectional view of an air strip line according to an embodiment of the present invention;

description of the drawings: 1, a first metal layer; 2, a second metal layer; 3, a first dielectric layer; 4, a third metal layer; 5, a second dielectric layer; 6, a fourth metal layer; 7, a fifth metal layer; 8, a third dielectric layer; 9, a sixth metal layer; 10, a seventh metal layer; 11, a fourth dielectric layer; 12, an eighth metal layer; 13, a ninth metal layer; 14, a fifth dielectric layer; 15, a tenth metal layer; 16, metallizing the through holes; 17, metallizing buried holes.

Detailed Description

The invention is further described by way of examples with reference to the accompanying drawings.

Preferred embodiment of the invention as shown in fig. 1 and 2, the air strip is a 10-layer hybrid board structure. Wherein, the thickness h1 of the first metal layer 1 to the tenth metal layer 15 is 0.035mm, the thickness h3 of the first dielectric layer 3, the thickness h3 of the third dielectric layer 8 and the thickness h3 of the fifth dielectric layer 14 are 0.254mm, and the thickness h2 of the second dielectric layer 5 and the thickness h2 of the fourth dielectric layer 11 are 0.508mm. The central conductor consists of traces of the same pattern on the fifth metal layer 7 and the sixth metal layer 9, the central conductor width w being 1mm and the thickness t being 0.324mm.

As can be seen from fig. 3, the center conductor is connected together by several metallized buried holes 17 from the fifth metal layer to the sixth metal layer 9, the diameter r2 of the metallized buried holes 17 is 0.2mm, the spacing l is 1mm, the width of the dielectric plate dug above and below the center conductor is a, a is twice the distance b between the two ground plates of the air strip line, b is 0.508mm x 2+0.254mm +0.035mm x 6+0.1mm x 4 = 1.88mm, so a is 3.76mm, the diameter r1 of several metallized through holes 16 on both sides of the center conductor is 0.2mm, which not only connects the ground of the first metal layer 1 to the tenth metal layer 15 together, but also plays a shielding role.

Claims

1. A novel air strip line, characterized in that:

the method sequentially comprises the following steps from top to bottom: the first metal layer, the first dielectric layer and the second metal layer; the third metal layer, the second dielectric layer and the fourth metal layer; a fifth metal layer, a third dielectric layer, and a sixth metal layer; a seventh metal layer, a fourth dielectric layer and an eighth metal layer; a ninth metal layer, a fifth dielectric layer, a tenth metal layer;

2. A novel air strip line according to claim 1, wherein: the center conductor of the air strip line comprises rectangular metal transmission lines with the same width on the fifth metal layer and the sixth metal layer, the rectangular metal transmission lines are connected through metallized buried holes from the fifth layer to the sixth layer, the metallized buried holes are uniformly distributed along the transmission lines from the starting end of the rectangular metal transmission lines, and the buried hole spacing is 1mm.

3. A novel air strip line according to claim 1, wherein: the second dielectric layer and the fourth dielectric layer above and below the center conductor of the air strip line are hollowed out in the direction along the center conductor to form a rectangular cavity having a width twice the distance between the two ground plates of the air strip line.

4. A novel air strip line according to claim 1, wherein: the upper grounding plate of the air strip line comprises a first metal layer, a second metal layer and the lower grounding plate comprises a ninth metal layer and a tenth metal layer.