CN105406160A - Conical G-line radio frequency transmission device for terahertz frequency band coaxial line waveguide - Google Patents

Abstract

A coaxial waveguide tapered G-line radio frequency transmission device in the terahertz frequency band proposed by the present invention aims to provide a simple structure, easy processing, which can realize super-strong energy gathering characteristics, and can improve terahertz imaging quality and signal enhancement Radio frequency transmission device for transmitting power. The present invention is achieved through the following scheme: the coaxial waveguide (1) is provided with a metal region (4), a dielectric region (5) and an outer metal layer (6) of the coaxial waveguide from the inside to the outside, and the coaxial waveguide (1) Through a section of deformed tapered G-line transition structure (2) transition interconnection tapered G-line (3), the external radio frequency signal passes through the coaxial waveguide (1) tail metal region (4) to the tapered G-line ( 3) Carry out radio frequency energy input, and carry out signal output from the tip of the tapered G line (3). The invention solves the problems in the prior art that the manufacturing technology of the terahertz waveguide structure is high, the practical application is difficult, and the processing is difficult.

Description

Terahertz frequency band coaxial waveguide tapered G-line radio frequency transmission device

technical field

The invention relates to a radio frequency transmission device that can be widely used in terahertz imaging and signal transmission.

Background technique

Electromagnetic waves with a frequency in the range of 0.1 to 10.0 THz are called terahertz waves. Between the millimeter wave frequency band and the infrared frequency band, the terahertz frequency band electromagnetic wave band belongs to the far infrared band, which has unique properties such as short wavelength, good directionality, low photon energy, and high penetration. The terahertz system is used in semiconductor materials, high-temperature superconducting The research on the properties of materials, tomographic imaging technology, marker-free genetic inspection, cell-level imaging, chemical and biological inspection, broadband communication, microwave orientation and many other fields have a wide range of applications. Due to the special location of THz wave, it has many superior characteristics and very important academic research and application value, which has attracted great attention from all countries in the world. Therefore, THz technology has gradually become a hot spot in international research. It is in the fields of basic research such as physics, chemistry, astronomy, life science and medicine. In addition to the source of terahertz signals, the application of terahertz must also solve the transmission problem of terahertz signals. Research on transmission lines is very important for the development of terahertz (THz) technology, which can effectively transmit terahertz signals and reduce the transmission loss of signals. Terahertz waves exhibit a series of special properties different from other electromagnetic radiation: strong penetrating ability, low photon energy, clear images with high resolution, time-resolved spectral measurements, etc. However, there are limitations in output frequency adjustability and output power of terahertz radiation sources and the problem that terahertz object imaging and high-power transmission require strong energy coupling at the radio frequency output end. Due to the strong influence of water vapor on THz waves It is urgent to study terahertz waveguides suitable for different application requirements. However, the lack of suitable waveguide materials and structures is an important reason restricting the development of terahertz technology.

How to effectively confine the electromagnetic field and carry out low-loss transmission is an important issue in the research of terahertz guided wave structures. Some terahertz guided wave structures have been proposed so far. Goubau line is a surface waveguide wave structure proposed by Goubau. It is formed by adding a layer of dielectric on the metal surface on the basis of the cylindrical metal wire waveguide structure. In the terahertz low frequency band (0.1-0.5THz), the Goubau line can realize low-loss transmission, and the transmission loss is 0.1-2.1m ^-1 . The outer dielectric layer can effectively confine the electromagnetic energy reflected by the metal, and the field confinement ability of the cylindrical G line is significantly enhanced compared with the metal wire waveguide structure.

In the terahertz frequency band, object imaging and high-power transmission usually require strong energy coupling characteristics at the output end. In order to enhance the energy aggregation characteristics, the invention improves the cylindrical G-line and uses a coaxial waveguide for RF signal input. , a new type of terahertz coaxial waveguide-tapered G-line radio frequency transmission device is proposed, which can achieve super energy concentration characteristics.

Contents of the invention

The purpose of the present invention is to provide a simple structure and easy to process for the limitation of the output power of the existing terahertz radiation source and the problem that the current terahertz object imaging and high power transmission require strong energy coupling at the radio frequency output end. Realize, a new type of terahertz band coaxial waveguide-tapered G-line radio frequency transmission device with a wide operating frequency band. The radio frequency transmission device can realize super-strong energy gathering characteristics, thereby improving the efficiency of transmitting and receiving terahertz signals, and is especially applicable to the entire 0.1THz-0.5THz terahertz frequency band.

The above object of the present invention can be achieved through the following technical solutions, a coaxial waveguide tapered G-line radio frequency transmission device in the terahertz frequency band, comprising a coaxial waveguide 1 and a tapered G-line 3, characterized in that: The waveguide 1 is provided with a metal region 4, a dielectric region 5, and a coaxial waveguide outer metal layer 6 from the inside to the outside. The coaxial coaxial waveguide 1 transitions and interconnects the tapered G line through a section of deformed tapered G line transition structure 2 3. The external radio frequency signal inputs radio frequency energy to the tapered G line 3 through the dielectric region 5 at the end of the coaxial waveguide 1 , and outputs the signal from the tip of the tapered G line 3 .

The present invention has following beneficial effects:

The structure is simple and easy to process. In the invention, the coaxial waveguide is used as the radio frequency signal input, and the transition structure is interconnected with the tapered G line through a section of deformed tapered G line transition structure, so as to output the radio frequency signal. The use of the coaxial waveguide can make it more convenient to connect with the outside. Compared with waveguide structures such as coplanar waveguides, slab waveguides, and dielectric fibers, the structural forms of coaxial waveguides and tapered G-lines have very obvious advantages. Their structures are simpler and their sizes are larger in comparison. , so that it is easier to process and realize, thereby solving the problems of high manufacturing process requirements, difficult practical application, and difficult processing of the existing terahertz guided wave structure.

Electromagnetic energy coupling strength is high. The coaxial coaxial waveguide 1 of the present invention transitions and interconnects the tapered G line 3 through a section of deformed tapered G line transition structure 2, and the external radio frequency signal performs radio frequency on the tapered G line 3 through the tail dielectric region 5 of the coaxial waveguide 1 Energy input, signal output from the tip of the tapered G line 3, effectively coupling the energy of the terahertz signal to the dielectric layer area, reducing the radiation loss of the terahertz signal in the external space, at the tip of the tapered G line It has super energy gathering characteristics, so as to realize high-efficiency coupling and improve the efficiency of transmission and reception of terahertz signals, which is difficult to achieve with the existing cylindrical G-lines. Compared with the cylindrical G-line, the tapered G-line has very little radiation field around it, and gathers most of the electromagnetic energy inside the waveguide, which can achieve stronger energy coupling at the output point of the tip.

The external radio frequency signal of the present invention uses the coaxial waveguide 1 to input radio frequency energy to the tapered G line 3, and then outputs the signal from the tip of the tapered G line. For coaxial waveguides and tapered G-lines of different sizes, a section of deformed tapered G-line transition structure 2 can be added between them for transitional interconnection. Because the tapered G-line propagates surface waves, the electromagnetic energy propagates on the metal surface, and the electromagnetic energy is bound by the external dielectric layer, so the electromagnetic energy has a super-strong coupling characteristic at the output point of the tip.

The coaxial waveguide tapered G-line radio frequency transmission device in the terahertz frequency band of the present invention realizes super-strong energy accumulation characteristics, is especially suitable for 0.1THz-0.5THz terahertz frequency band, terahertz imaging, and can effectively enhance signal transmission power and coupling strength An adjustable radio frequency transmission device in the terahertz frequency band.

Description of drawings

Fig. 1 is an exploded schematic view of the coaxial waveguide-tapered G-line radio frequency transmission device in the terahertz frequency band of the present invention.

In the figure: 1 coaxial waveguide, 2 deformed tapered G-line transition structure, 3 tapered G-line. 4 inner metal area, 5 dielectric area, 6 coaxial waveguide outer metal layer of coaxial waveguide.

detailed description

See Figure 1. In the embodiments described below, the coaxial waveguide tapered G-line radio frequency transmission device in the terahertz frequency band includes a coaxial waveguide 1 and a tapered G-line 3 . The coaxial waveguide 1 is provided with a metal region 4, a dielectric region 5 and an outer metal layer 6 of the coaxial waveguide from the inside to the outside. Connecting the tapered G line 3 , the external radio frequency signal enters the tapered G line 3 through the dielectric region 5 at the end of the coaxial waveguide 1 , and outputs the signal from the tip of the tapered G line 3 . The large end of the deformed tapered G-line transition structure 2 is butted and fixedly connected to the large end of the tapered G-line 3 , and the small end of the deformed tapered G-line transition structure 2 is butted and fixedly connected to the end surface of the outer metal layer 6 of the coaxial waveguide. The external radio frequency signal adopts the coaxial waveguide 1 to carry out energy input to the tapered G line 3, and then outputs the signal from the tip. For coaxial waveguides and tapered G lines of different sizes, a section of deformation can be added between the two Tapered G-line transition structure 2 for transition interconnection. Because the tapered G-line propagates surface waves, the electromagnetic energy propagates on the metal surface, and the electromagnetic energy is bound by the external dielectric layer, so the electromagnetic energy has a strong coupling effect at the output point of the tip. The invention can improve the terahertz imaging quality and enhance the signal transmission power.

The concrete implementation of the present invention can adopt following steps:

First, according to the frequency band requirements of the terahertz circuit, determine the frequency passband, select the appropriate outer dielectric material, use the microwave circuit computer aided software to establish the guided wave structure in Figure 1, set the required transmission characteristic design goals, and optimize the software Design a program to determine the transmission line parameters of each unit.

Claims (2)

1. a Terahertz frequency range coaxial line waveguide taper G line radio frequency transmission device, comprise coaxial line waveguide (1) and taper G line (3), it is characterized in that: coaxial line waveguide (1) is provided with metallic region (4) from inside to outside, areas of dielectric (5) and coaxial line waveguide external metal level (6), this coaxial coaxial line waveguide (1) is by one section of distortion taper G line transition structure (2) transition interconnection taper G line (3), external radio-frequency signal carries out radio-frequency (RF) energy input by coaxial line waveguide (1) to taper G line (3), signal output is carried out from the most advanced and sophisticated position of taper G line (3).

2. Terahertz frequency range coaxial line waveguide taper G line radio frequency transmission device as claimed in claim 1, it is characterized in that: distortion taper G line transition structure (2) is held greatly docking to connect firmly taper G line (3) and held greatly, the small end docking of distortion taper G line transition structure (2) connects firmly on the end face of coaxial line waveguide external metal level (6).