CN-122000653-A - Non-contact terahertz waveguide switch

CN122000653ACN 122000653 ACN122000653 ACN 122000653ACN-122000653-A

Abstract

The application provides a non-contact terahertz waveguide switch which comprises a multipath waveguide module, a linear motor and an electromagnetic band gap structure, wherein the multipath waveguide module comprises 3 paths of waveguides which are respectively pointed in 3 directions and are used for receiving observation signals, the receiving waveguide is used for receiving electromagnetic waves from the multipath waveguide module and is connected with a rear end receiver, the linear motor is used for bearing the multipath waveguide module, the switching communication of different waveguide channels of the receiving waveguide and the multipath waveguide module is realized through linear motion, the electromagnetic band gap structure is arranged between the receiving waveguide and the multipath waveguide module, and the electromagnetic band gap structure comprises a plurality of two-dimensional rectangular array ordered metal microcolumns, and the metal microcolumns are fixed on one side, adjacent to the receiving waveguide, of the multipath waveguide module and have set gaps with the receiving waveguide. The application has the advantages of minimizing mechanical parts, compacting the size of the whole system, reducing weight and power consumption, improving the reliability and service life of equipment and reducing operation and maintenance cost and shutdown loss.

Inventors

YU YANG
ZHU HAOTIAN
ZHANG DEHAI

Assignees

中国科学院国家空间科学中心

Dates

Publication Date: 20260508
Application Date: 20260114

Claims (7)

1. A non-contact terahertz waveguide switch, comprising: The multipath waveguide module comprises 3 paths of waveguides which are respectively pointed in 3 directions and are used for receiving observation signals; The receiving waveguide is used for receiving electromagnetic waves from the multipath waveguide module and is connected with the rear end receiver; The linear motor is used for bearing the multipath waveguide module and realizing the switching communication between the receiving waveguide and different waveguide channels of the multipath waveguide module through linear motion; An electromagnetic band gap structure is arranged between the receiving waveguide and the multipath waveguide module; the electromagnetic band gap structure comprises a plurality of metal microcolumns which are arrayed in a two-dimensional rectangular mode, are fixed on one side, adjacent to the receiving waveguides, of the multipath waveguide module, and have set gaps with the receiving waveguides.
2. The non-contact terahertz waveguide switch of claim 1, wherein the set gap is 0-65 μm.
3. The non-contact terahertz waveguide switch of claim 1, wherein the electromagnetic bandgap structure has 3 waveguide ports corresponding to 3 waveguides respectively along a direction of motion of a linear motor.
4. The non-contact terahertz waveguide switch of claim 3, wherein a spacing between two adjacent waveguide ports is greater than 0.886mm, less than a range of travel of the linear motor.
5. The non-contact terahertz waveguide switch of claim 1, wherein the metal microcolumn is in the shape of a cuboid having a square cross section.
6. The non-contact terahertz waveguide switch of claim 5, wherein the metal microcolumns have a width of 120 μm and a height of 117 μm, and the interval between adjacent metal microcolumns is 135 μm.
7. The non-contact terahertz waveguide switch of claim 1, further comprising: And the mounting base is used for bearing the multipath waveguide module, the receiving waveguide and the linear motor and controlling the interval between the multipath waveguide module and the receiving waveguide.

Description

Non-contact terahertz waveguide switch Technical Field The application belongs to the field of terahertz remote sensing, and particularly relates to a non-contact terahertz waveguide switch. Background Terahertz is an electromagnetic wave covering 0.1-10 THz. The absorption or emission spectrum line formed by partial gas molecules rotating around the symmetry axis falls in the microwave, millimeter wave and terahertz frequency bands. We can obtain information about gas molecules by observing the spectral line structure falling in these bands, which is an ability not possessed by near infrared and visible light spectra. The microwave radiometer with high sensitivity is an important detector in the field of passive remote sensing, and can be used for acquiring the brightness temperature data of the atmosphere or substances of the planet and the satellite thereof, and then obtaining various physical parameters of a measured target and a propagation medium through inversion. In order to realize quantitative detection and scientific application of the terahertz radiometer to an observation target, data are acquired in real time and accurately, and the radiometer needs to be calibrated. The calibration system is an important component of the terahertz radiometer detector, and determines the detection precision of the radiometer system. Radiometer calibration requires two or more calibration references (also known as calibration sources) of different temperatures of known radiation characteristics, which are periodically switched by a calibration switch to receive a radiation signal of precisely known microwave radiation characteristics (brightness temperature), thereby constructing a quantitative relationship between radiometer electrical signal output and received radiation magnitude. The common method is to place the calibration body outside the receiver (i.e. external calibration), and use a mechanical rotation device to control the switching of the quasi-optical reflector, so that the receiving antenna period points to cold air and a known temperature heat source to realize calibration. The problem faced by this solution is that the scaling means occupy the weight, volume and power consumption of a larger payload. In particular for deep space exploration applications, it is necessary to carry as much payload as possible, which limits the distance and range of the deep space exploration application if the footprint of the calibration device is large. For the above problems, the radiometer receiving system (i.e. internal calibration) can be built in the calibration source, mechanical components can be minimized, and the whole system can be compact in size, and weight and power consumption can be reduced. Therefore, the conventional switching device of the larger rotating mechanism can be replaced by a waveguide switching device, so that the whole calibration source switching device is more compact. For terahertz frequency bands, the technology of waveguide switches is still less researched, and particularly, a sub-millimeter wave band above 300 GHz is not good in technical scheme. Switching schemes based on integrated circuits have been developed for many years with wider applications, but mainly for the microwave and millimeter wave bands. The advantage of this solution is that the switching speed is fast, but the insertion loss of the integrated circuit based switch is high (generally higher than 2.5 dB), and the isolation is poor. High insertion loss can severely degrade system noise, and performance is difficult to meet the requirements of higher frequency sub-millimeter wave applications greater than 300 GHz. At present, researches on frequency bands above terahertz 300 GHz mainly use a motor or a micro-electromechanical driver with a mechanical structure to realize switching of waveguide transmission. 2024, U.S. jet-power laboratory (JPL) developed a MEMS-based 500-750GHz rotary single pole double throw waveguide switch, in which the waveguide can be switched in the ±4.5° range by a rotating structure, but due to process and design issues, the insertion loss was higher than 2.5dB. In addition, a single pole double throw terahertz waveguide switch based on linear motor drive is reported by JPL in the United states. The defect is that the number of switching channels is limited, the U-shaped waveguide switching slide block is only suitable for a single-pole double-throw switching mode, and the working frequency is lower and is 250-310 GHz. Disclosure of Invention The application aims to overcome the defects of high insertion loss, limited number of switching channels, suitability for single-pole double-throw switch modes and low working frequency in the prior art. In order to achieve the above object, the present application proposes a non-contact terahertz waveguide switch, comprising: The multipath waveguide module comprises 3 paths of waveguides which are respectively pointed in 3 directions and are used