Controllable hybrid electromagnetic coupling filter

Abstract

The invention discloses a controllable hybrid electromagnetic coupling filter. The controllable hybrid electromagnetic coupling filter comprises at least two 1 / 4 wavelength stepped impedance resonators, a metal conduction band, a coupling slot and metallization via holes, wherein magnetic coupling and electrical coupling are respectively achieved by connecting the metal conduction band at high-resistance ends of the adjacent 1 / 4 wavelength stepped impedance resonators 1 and the coupling slot between low-resistance ends of the adjacent 1 / 4 wavelength stepped impedance resonators 1 by the filter, and the intensity of magnetic coupling and the intensity of electrical coupling are controlled by adjusting the size of the coupling slot and the distance from the metal conduction band to the metallization via holes. The controllable hybrid electromagnetic coupling filter controls the size of electrical coupling components and the size of magnetic coupling components conveniently, and effectively introduces controllable hybrid electromagnetic coupling among a plurality of the adjacent resonators, thereby obtaining more transmission zeros, lowering the order, improving frequency selectivity and stop band characteristics, and effectively reducing inserting loss and the size.

Description

technical field [0001] The present invention relates to an electromagnetic coupling filter, in particular to a controllable hybrid electromagnetic coupling filter which simultaneously introduces controllable electric and magnetic hybrid coupling between adjacent 1 / 4 wavelength stepped impedance resonators to generate a finite transmission zero point . Background technique [0002] Modern wireless communication systems require filters with characteristics such as small size, low insertion loss, high frequency selectivity and stop bandwidth. In order to improve the frequency selectivity of the filter, it can usually be achieved by increasing the filter order, but at the same time the insertion loss and area of ​​the filter are increased; it can also be achieved by introducing transmission zeros, which can improve while reducing the filter order. Frequency selectivity and stopband characteristics of filters. The introduction of transmission zeros usually adopts cross-coupling...

AI Technical Summary

Problems solved by technology

This kind of structure that only relies on the coupling gap to achieve hybrid electromagnetic coupling is difficult to control the magnitude of the electric and magnetic coupling components conveniently, and on the other hand it is difficult to effectively introduce controllable hybrid electromagnetic coupling between multiple adjacent resonators at the same time.

To realize N controllable finite transmission zeros, N second-order hybrid electromagnetic coupling units are often required to be cascaded, and there is only a single electrical coupling or magnetic coupling between adjacent second-order hybrid electromagnetic coupling units, greatly Increased filter order

In addition, filters based on 1 / 2-wavelength stepped-impedance resonators not only occupy twice the area compared to 1 / 4-wavelength stepped-impedance resonators, but the stop-band performance is also more difficult to control

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