CN110212275B

CN110212275B - Millimeter wave waveguide matching load based on lossy dielectric substrate

Info

Publication number: CN110212275B
Application number: CN201910635706.8A
Authority: CN
Inventors: 宋开军; 郭松; 陈宇旋; 夏飞; 樊勇; 程钰间
Original assignee: University of Electronic Science and Technology of China
Current assignee: University of Electronic Science and Technology of China
Priority date: 2019-07-15
Filing date: 2019-07-15
Publication date: 2021-06-04
Anticipated expiration: 2039-07-15
Also published as: CN110212275A

Abstract

The invention relates to a millimeter wave waveguide matching load based on a lossy dielectric substrate. The quasi-planar waveguide matched load is realized by adopting a planar lossy dielectric substrate. The millimeter wave waveguide matching load based on the lossy dielectric substrate is composed of an upper copper-clad substrate and a lower copper-clad substrate which share a middle copper-clad layer. Microwave signals are fed in from a standard waveguide port and enter a rectangular cavity of the upper layer copper-clad substrate, a high-order mode is excited in the rectangular cavity, the high-order mode is coupled to three lossy rectangular resonant cavities of the lower layer copper-clad substrate through interlayer coupling gaps, the high-order mode is reflected back and forth in the three lossy rectangular resonant cavities, electromagnetic energy of the high-order mode is absorbed by the lower layer lossy medium substrate and is finally converted into heat energy, and the function of matching loads by waveguides is achieved. The waveguide load solves the problems of high cost, large volume and complex processing and assembly of the traditional waveguide load, and is particularly suitable for various wave millimeter wave measurement and communication systems.

Description

Millimeter wave waveguide matching load based on lossy dielectric substrate

Technical Field

The invention belongs to the technical field of wireless communication systems, and relates to a millimeter wave waveguide matching load based on a lossy dielectric substrate.

Background

The waveguide matching load is a common element in the microwave and millimeter wave field, and is commonly used in a microwave and millimeter wave measurement system and a communication system. The performance of the system directly influences the performance of the whole system. Especially in the power dividing network of the antenna feed of microwave and millimeter wave frequency band and the synthesizing network for power synthesis, the matching load with simple structure, miniaturization and low cost has wide application. Conventional matched loads are typically made by mounting a wedge-type material or a resistive material within the waveguide. However, as communication systems develop to higher transmission frequencies, especially millimeter wave/terahertz systems, the material size thereof becomes smaller and smaller, and is limited by the circuit space volume and the processing technology, and it is difficult to develop a high-performance and low-cost matching load. The research and development of planar, miniaturized and low-cost matched loads are of great significance to the development of modern microwave millimeter wave systems.

Disclosure of Invention

In view of the defects in the prior art, the invention provides a millimeter wave waveguide matched load based on a lossy dielectric substrate. The planar lossy dielectric substrate is adopted to realize the quasi-planar waveguide matched load, the problems of high cost, large volume, complex processing and assembly and the like of the traditional millimeter wave waveguide matched load can be solved, and the planar lossy dielectric substrate is particularly suitable for various millimeter wave measurement and communication systems.

In order to achieve the purpose, the invention provides the following technical scheme:

fig. 1 and fig. 2 show a millimeter wave waveguide matching load based on a lossy dielectric substrate. The millimeter wave waveguide matching load is composed of an upper copper-clad substrate and a lower copper-clad substrate which share a middle copper-clad layer (5), wherein: the upper copper-clad substrate comprises an upper copper-clad layer (1), an upper dielectric substrate (3), a middle copper-clad layer (5) and an upper dielectric substrate metalized through hole (4), the standard waveguide input port (2) is etched on the upper copper-clad layer (1), and the upper dielectric substrate metalized through hole (4) is surrounded to form a closed rectangular cavity; the lower copper-clad substrate comprises a middle copper-clad layer (5), a lower lossy dielectric substrate (7), a lower copper-clad layer (9) and a lower lossy dielectric substrate metalized through hole (8), the lower lossy dielectric substrate (7) is a lossy dielectric substrate, the lower lossy dielectric substrate metalized through hole (8) surrounds three lossy rectangular resonant cavities, and the matching metal column (10) is positioned in the rightmost lossy rectangular resonant cavity; etching an interlayer coupling gap (6) on the middle copper-clad layer (5); the standard waveguide input port (2) of the millimeter wave waveguide matching load based on the lossy dielectric substrate is connected with the standard waveguide, aligned and positioned with the standard waveguide through a waveguide flange pin hole (11), and connected and fixed through a waveguide flange mounting hole (12).

The working principle of the millimeter wave waveguide matched load based on the lossy dielectric substrate is as follows:

microwave signals are fed into a standard waveguide input port (2) of the millimeter wave waveguide matching load based on the lossy dielectric substrate from a standard waveguide, enter a rectangular cavity of the upper layer copper-clad substrate, and are excited to form a high-order mode in the rectangular cavity, the high-order mode is coupled into a lossy rectangular resonant cavity of the lower layer copper-clad substrate through an interlayer coupling gap (6), the high-order mode is reflected back and forth in three lossy rectangular resonant cavities of the lower layer copper-clad substrate, electromagnetic energy of the high-order mode is absorbed by the lower layer lossy dielectric substrate (7), and finally the high-order mode is converted into heat energy, so that the function of matching the waveguide load is achieved. The technology provided by the invention can meet the requirements of millimeter wave measurement and communication systems, and has great application value.

The invention has the advantages and obvious effects that:

the millimeter wave waveguide matching load based on the lossy dielectric substrate adopts a planar copper-clad substrate structure and is based on a conventional PCB substrate processing technology, so that the planarization, low cost and miniaturization characteristics of the millimeter wave matching load are realized, and the problems of large volume, high cost, difficult processing and complex assembly of the traditional millimeter wave waveguide matching load are solved.

The millimeter wave waveguide matching load based on the lossy dielectric substrate has the advantages of low section, low cost, easiness in processing, simplicity in assembly and the like. The invention is mainly applied to various millimeter wave systems, and has wide application prospect in millimeter wave systems such as communication, radar, measurement and control and the like.

Drawings

Fig. 1 is a schematic diagram of a millimeter wave waveguide matching load based on a lossy dielectric substrate according to the present invention;

FIG. 2 is a top view of the millimeter wave waveguide matching load based on the lossy dielectric substrate proposed by the present invention;

FIG. 3 is a side view of the millimeter wave waveguide matched load based on the lossy dielectric substrate proposed by the present invention;

FIG. 4 is a simulation curve of S-parameters of a W-band lossy dielectric substrate-based millimeter wave waveguide matched load in an exemplary implementation;

in the drawings, the reference numbers correspond to the names:

(1) the waveguide structure comprises a copper-clad layer, (2) a standard waveguide input port, (3) an upper dielectric substrate, (4) a metalized through hole of the upper dielectric substrate, (5) a middle copper-clad layer, (6) an interlayer coupling gap, (7) a lower lossy dielectric substrate, (8) a metalized through hole of the lower lossy dielectric substrate, (9) a lower copper-clad layer, (10) a matching metal column, (11) a waveguide flange pin hole, and (12) a waveguide flange mounting hole.

Detailed Description

The present invention will be described in detail below by way of examples.

Fig. 1, fig. 2 and fig. 3 show the millimeter wave waveguide matching load based on the lossy dielectric substrate in the present invention. And selecting the working frequency band matched with the load to be 93-97 GHz. The standard waveguide input port is a WR-10 standard rectangular waveguide input port, and the standard waveguide dimension is 2.54mm multiplied by 1.27 mm. The upper copper-clad substrate used was a Taconic RF-35 dielectric substrate having a dielectric constant of 3.5, a loss tangent of 0.0018 and a thickness of 0.508 mm. The lower copper-clad substrate used was an FR4 high loss dielectric substrate having a dielectric constant of 4.2, a loss tangent of 0.02 and a thickness of 1 mm.

Claims

1. The millimeter wave waveguide matching load based on the lossy dielectric substrate is characterized by being composed of an upper copper-clad substrate and a lower copper-clad substrate which share a middle copper-clad layer (5), wherein: the upper copper-clad substrate comprises an upper copper-clad layer (1), an upper dielectric substrate (3), a middle copper-clad layer (5) and an upper dielectric substrate metalized through hole (4), the standard waveguide input port (2) is etched on the upper copper-clad layer (1), and the upper dielectric substrate metalized through hole (4) is surrounded to form a closed rectangular cavity; the lower copper-clad substrate comprises a middle copper-clad layer (5), a lower lossy dielectric substrate (7), a lower copper-clad layer (9) and a lower lossy dielectric substrate metalized through hole (8), the lower lossy dielectric substrate (7) is a lossy dielectric substrate, the lower lossy dielectric substrate metalized through hole (8) surrounds three lossy rectangular resonant cavities, and the matching metal column (10) is positioned in the rightmost lossy rectangular resonant cavity; etching an interlayer coupling gap (6) on the middle copper-clad layer (5); the standard waveguide input port (2) of the millimeter wave waveguide matching load based on the lossy dielectric substrate is connected with the standard waveguide, aligned and positioned with the standard waveguide through a waveguide flange pin hole (11), and connected and fixed through a waveguide flange mounting hole (12).

2. The millimeter wave waveguide matched load based on the lossy dielectric substrate of claim 1, wherein a higher order mode is excited in a rectangular cavity of the upper copper-clad substrate; the rectangular cavity of the upper layer copper-clad substrate and the lossy rectangular resonant cavity of the lower layer copper-clad substrate are coupled through an interlayer coupling gap (6).

3. The millimeter wave waveguide matched load based on a lossy dielectric substrate according to claim 1, wherein the high-order mode is reflected back and forth in three lossy rectangular resonant cavities of the lower copper-clad substrate, and the electromagnetic energy of the high-order mode is absorbed by the lower lossy dielectric substrate (7) and finally converted into heat energy, so that the function of waveguide matched load is realized.