Method for inhibiting microwave filter parasitize pass band based on frequency change metallicity like material

A microwave filter and parasitic passband technology, applied in waveguide devices, electrical components, circuits, etc., can solve the problems of unadjustable structure, unchangeable medium parameters, and destruction of useful information, so as to improve design efficiency, easy implementation, The effect of simple structure

Inactive Publication Date: 2008-07-23
SHANGHAI JIAO TONG UNIV
View PDF0 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The disadvantage of this structure is that due to the fixed size of the small waveguide and the invariable dielectric parameters of the microwave absorbing material, the structure is not adjustable and cannot be applied to the suppression of the spurious passband of the adjustable filter, and because this method uses microwave absorbing material Absorbs electromagnetic waves higher than the cutoff frequency of the small rectangular waveguide, making this method unsuitable for frequency division communication, and will cause incalculable damage to the useful information of adjacent channels
In addition, this method requires the addition of small waveguides between adjacent resonators, which destroys the basic filtering structure of the filter

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0020] to suppress the 3ω of parallel inductively coupled rectangular waveguide filters 0 Take the parasitic passband as an example. This type of microwave filter uses a rectangular waveguide section with a half waveguide wavelength as a series resonator, and uses a parallel inductor metal die as a coupling structure between resonators. Its rectangular waveguide model is the national label model BJ-32, its wide side is 72.14mm and narrow side is 34.04mm, the center frequency of the main passband is 3.1GHz, 2ω 0 The center frequency of the parasitic passband is 5.0467GHz, 3ω 0 The central frequency of the parasitic passband is 7.2043GHz. 2ω 0 and 3ω 0 The central frequency of the parasitic passband at g0 / 2 and λ g0 / 3 is calculated. The following is a detailed description of this embodiment:

[0021] In the first step, the oblique symmetrical probe coupling method is used as the input and output coupling structure of the microwave filter. By matching the input and outp...

Embodiment 2

[0028] In this embodiment, the basic filtering structure of the microwave filter is the same as that in Embodiment 1. Similarly, this embodiment suppresses the filter's 3ω 0 for the purpose of parasitic passband. The difference from Example 1 is that the cold plasma generated by ionized neon gas is used as the frequency-variable metal-like material, and some other parameters are changed, such as the distance between the probe and the plasma interface and the thickness of the plasma layer. In this embodiment, due to the change of these parameters, the center frequency of the main passband has a slight change to 3.125GHz, corresponding to 2ω 0 The center frequency of the parasitic passband is 5.1080GHz, 3ω 0 The central frequency of the parasitic passband is 7.3009GHz. The following is a detailed description of this embodiment:

[0029] In the first step, the oblique symmetrical probe coupling method is used as the input and output coupling structure of the microwave filter....

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention provides a method for basing on that frequency-dependent metallicity material inhibits microwave filter parasitic pass band belonging to the technology field of microwave communication, through a manner of an actuation probe in input and output coupling structure of the filter and increasing frequency-dependent metallicity material among short-circuiting pistons, in contrast to center frequency of the filter, the actuation probe is positioned on a potential antinodal point, and in contrast to center frequency of the parasitic pass band, the actuation probe is positioned on a potential nodal-point, thereby inhibiting the parasitic pass band. The invention not only can inhibit the parasitic pass band which is in even multiple frequencies of the center frequency, but also can inhibit the parasitic pass band which is in odd multiple frequencies of the center frequency, furthermore, and has the advantages of adjustability, wide applicability, simple structure and easy realization and the like.

Description

technical field [0001] The invention relates to a method for suppressing a parasitic passband of a microwave filter in the technical field of radar and microwave communication, in particular to a method for suppressing a parasitic passband of a microwave filter based on a frequency-varying metal-like material. Background technique [0002] Microwave filters are generally composed of multiple resonators and coupling structures. They have the characteristics of simple structure and easy design, and are widely used in the field of microwave communication. However, due to the multiple resonance characteristics of the resonator, in the frequency response of the microwave filter, except for the center frequency ω 0 located outside the operating passband, still with ω 0 There are spurious passbands at integer multiples of frequency. The existence of these parasitic passbands will affect the normal operation of the system and cause serious electromagnetic compatibility (EMC) probl...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): H01P1/212H01P1/20
Inventor 袁斌刘天胜张凌峰梅涛
Owner SHANGHAI JIAO TONG UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products