Cross-coupled filter

Abstract

The invention discloses a cross-coupled filter, which comprises a minimum resonance structure, the minimum resonance structure is composed of four resonators, in the minimum resonance structure, two resonators in the same row form a group, and the two resonators in the same row are mainly electrically coupled or magnetically coupled; the two resonators in the same column are electromagnetically mixed and coupled; and the coupling polarities of the two groups of resonators of the two rows of resonance units are opposite, and at least one cross coupling is formed. According to the invention, miniaturization and light weight are realized in terms of structural characteristics, and low loss and good harmonic characteristics are realized in terms of electrical performance.

Description

technical field [0001] The present invention relates to a filter, in particular to a cross-coupling filter. Background technique [0002] The recent demand trend for filters is miniaturization and high quality. In particular, the communication components used in the small base stations of 5G communications are smaller in size and more in demand than the previous macro base station products. Therefore, the components used in the product must also achieve high-quality miniaturization, light weight, and a structure suitable for mass production. [0003] The filters currently used in small base stations are usually dielectric waveguide filters and traditional metal coaxial filters. The dielectric waveguide filter can be miniaturized and lightweight, and the manufacturing cost is low, but its loss and harmonic characteristics are worse than that of the metal coaxial filter. Traditional metal coaxial filters have better loss and harmonic characteristics than dielectric waveguide...

AI Technical Summary

Problems solved by technology

However, this structure still has the following disadvantages: 1. Although the multiple bending of the resonator is conducive to miniaturization, relatively speaking, the decrease in the Q value leads to the deterioration of the insertion loss in the electrical performance of the filter; and when the mold is opened to make the product , the component volume is relatively smaller than ordinary filters and there are bends, and there is a possibility of deformation during die-casting; 2. It is necessary to improve the harmonic characteristics of the 2-fold frequency

However, this structure still has the following disadvantages: 1. Although the multiple bending of the resonator is conducive to miniaturization, relatively speaking, the decrease in the Q value leads to the deterioration of the insertion loss in the electrical performance of the filter; 2. In order to strengthen the resonance of each layer For the amount of coupling between units, the window on the shielding layer must be opened very large, which brings certain restrictions to increasing the bandwidth; 3. The initial direction of the resonator is single, and the change of the coupling form is limited

[0008] Therefore, it is necessary to propose a new type of miniaturized and lightweight filter to solve the problems of insertion loss and suppression in the electrical performance of the above-mentioned filter, the possibility of deformation during die-casting, and the need for double frequency Harmonic improvement and other issues

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