Adjustable bandstop filter

Abstract

The invention discloses an adjustable bandstop filter, and relates to the technical field of microwave communication. The adjustable bandstop filter comprises a bandstop filter main body internally provided with a main body circuit, wherein the main body circuit is electrically connected with a plurality of electrodes, the electrodes are arranged outside the bandstop filter main body, a tuning element is arranged outside the bandstop filter main body, is electrically connected with the main body circuit and is used for changing a transmission zero point of the main body circuit, and the main body circuit is manufactured based on a low-temperature co-fired ceramic process. According to the invention, the adjustable bandstop filter is small in size, and based on the low-temperature co-firedceramic technology, the circuit of the filter is compact in structure and good in repeatability; the stop band width and the in-band rejection depth are flexibly adjustable, and the transmission zeropoint position of the bandstop filter can be reset by changing the value of an external tuning element, so that the filter can be conveniently switched between wide stop band and high rejection in different required environments; the insertion loss is small; and the filter achieves a high suppression level in a small size, and can effectively filter out various useless signals and noise signals.

Description

technical field [0001] The invention relates to the technical field of microwave communication, in particular to an ultra-small adjustable band-stop filter. Background technique [0002] The traditional band-stop filter design structure is generally composed of quarter-wavelength stub resonators, which are arranged along the main waveguide or main transmission line, and the interval between the resonators is an odd multiple of the quarter-wavelength. The square coefficient of the reject filter is not ideal and bulky. In recent years, with the emergence of new materials and process technologies such as micro-electromechanical systems (MEMS) technology, high-temperature superconducting technology, low-temperature co-fired ceramics (LTCC) technology, photonic bandgap structure, and microwave monolithic integrated circuits, the filter Continuous improvement from performance to volume. With the continuous development of wireless communication systems and microwave and millimete...

AI Technical Summary

Problems solved by technology

However, the working bandwidth of the band-stop filter is relatively narrow, and the processing technology requirements are relatively high. Once the precision control deviates, the working frequency is easy to shift

In addition, compared with chip-level multilayer circuit components, the size of the filter is still large, and it is difficult to integrate in increasingly miniaturized wireless communication terminal equipment

The document with the application number 201410290334.7 discloses an ultra-wideband band-stop filter based on multi-step impedance resonator loading, which uses the open-circuit characteristics of multiple step impedance resonators to generate five transmission zeros on the stop band, Ultra-wide stopband characteristics are realized, but since the resonator microstrip lines all adopt the electrical length of a quarter wavelength and are made on a double-sided copper-clad microstrip board with a dielectric constant of 2.2, the occupied The area is large, and it is also difficult to meet the stringent volume requirements of highly integrated wireless communication terminals for RF components such as filters

Images