A miniaturized liquid crystal tunable microwave narrowband band-stop filter and its processing method
A band-stop filter, microwave technology, applied in waveguide-type devices, circuits, electrical components, etc., can solve the problems of unsuitable isolation of narrow-band signals, large stop-band bandwidth, complex process, etc., to solve the problem of signal interference and insertion loss. Low, simple to prepare effect
Active Publication Date: 2020-02-18
SOUTHEAST UNIV
View PDF4 Cites 0 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
However, there are not many adjustable microwave band-stop filters realized by liquid crystal technology at present, and the stop-band bandwidth is large, which is not suitable for isolating narrow-band signals.
In addition, liquid crystal materials are different from traditional solid-state dielectrics in that they have flowability. In the prior art, holes are usually drilled on the upper substrate to realize the connection between the SMA and the microstrip structure of the device. This method is more complicated and increases the production cost, and It is easy to have impedance mismatch problem, which increases the microwave reflection signal
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 moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment Construction
[0025] The technical solution of the present invention will be further introduced below in conjunction with specific embodiments.
[0026] This specific embodiment discloses a miniaturized liquid crystal tunable microwave narrow band rejection filter, such as figure 1 with figure 2 As shown, it includes a dielectric substrate 1, a microstrip line 2 is provided at the bottom of the dielectric substrate 1, and the microstrip line 2 forms a dual resonance structure; it also includes a ground plate 4, and a liquid crystal layer 3 is provided between the bottom of the dielectric substrate 1 and the top of the ground plate 4 , The two ends of the top of the ground plate 4 are etched so that SMA connectors can be inserted into both ends of the ground plate 4 and achieve 50 ohm impedance matching. The portions etched at both ends of the ground plate 4 are not in contact with the liquid crystal layer 3. The dual-resonant structure includes an open-circuit branch, and the length of the op...
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
| Property | Measurement | Unit |
|---|---|---|
| thickness | aaaaa | aaaaa |
| thickness | aaaaa | aaaaa |
| length | aaaaa | aaaaa |
Login to View More
Abstract
The invention discloses a miniaturized liquid crystal adjustable microwave narrowband rejection filter comprising a dielectric substrate. A microstrip line is arranged on the bottom part of the dielectric substrate. The microstrip line forms a double resonance structure. The filter also comprises a grounding plate. A liquid crystal layer is arranged between the bottom part of the dielectric substrate and the top part of the grounding plate. The two ends of the top part of the grounding plate are etched so that an SMA connector is enabled to be inserted into the two ends of the grounding plateto realize 50ohm impedance matching. The invention also discloses a processing method of the filter. The two ends of the grounding plate are etched, and insertion and impedance matching of the SMA connector can be realized without drilling holes on the dielectric substrate; the double resonance structure is used, and the miniaturized liquid crystal adjustable microwave narrowband rejection filterhaving excellent performance can be realized through combination of the anisotropy of the liquid crystal material; and the WiMAX signal interference problem in ultra-wideband communication can be solved and the filter has the advantages of low insertion loss, continuously adjustable property, compact structure, simple preparation, low cost and convenient integration.
Description
Technical field [0001] The invention relates to a microwave device, in particular to a liquid crystal adjustable microwave narrow-band band rejection filter and a processing method thereof. Background technique [0002] As a frequency selective device, the band stop filter is widely used in the field of communication technology, and it is one of the key devices in modern wireless communication systems. However, it is difficult for the current traditional band stop filter to realize the adjustable function, and it will increase the cost and complexity of production applications and systems. As a new type of filter with flexible performance, adjustable band stop filter can not only isolate and attenuate unwanted signals, but also adjust the frequency selection characteristics according to actual needs and environment. [0003] At this stage, there are four main technologies commonly used to implement tunable band-stop filters: electrical methods, such as PIN diodes, varactor diodes,...
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
Login to View More Patent Type & Authority Patents(China)
IPC IPC(8): H01P1/203H01P11/00
CPCH01P1/203H01P11/007
Inventor 蔡龙珠洪伟
Owner SOUTHEAST UNIV