Bandwidth controllable high-frequency-ratio coaxial cavity dual-frequency filter

Abstract

The invention discloses a bandwidth controllable high-frequency-ratio coaxial cavity dual-frequency filter comprising a first coaxial cavity, a second coaxial cavity, an input port, an output port, afirst rectangular metal coupling piece, a second rectangular metal coupling piece, a first step impedance wafer loading resonator, a second step impedance wafer loading resonator and a coupling window. The whole filter structure is a symmetrical structure about the center of the coupling window. The cavity dual-frequency filter with controllable center frequency can be realized and the high frequency ratio characteristic between two passband center frequencies can also be realized. Meanwhile, the bandwidth of the two pass-bands can be controlled independently within a certain range, and the advantages of the filter are small size, high power capacity and simple design and processing so that the design requirements of small dual-frequency communication systems can be met and the filter canbe applied to mobile communication, radar, satellite and other microwave electronic systems.

Description

technical field [0001] The invention relates to a cavity filter, in particular to a coaxial cavity dual-frequency filter with a large frequency ratio and controllable bandwidth. Background technique [0002] With the rapid development of wireless communications, spectrum resources are becoming increasingly scarce. In order to reduce communication costs and improve spectrum utilization, dual-frequency filters, as the most commonly used multi-frequency filters, have become a research hotspot because they can be compatible with two different standards of the key components of the dual-frequency communication system front-end. Due to the advantages of low insertion loss, high Q value (quality factor), high power capacity and high stability, coaxial cavity dual-frequency filters have been widely used in narrowband communications with high selectivity, especially in coaxial cavity Filter-based radio frequency filters are still one of the key equipment in mobile communication base...

AI Technical Summary

Problems solved by technology

However, it is difficult for filters in the prior art to achieve a large frequency ratio when the two passband bandwidths are controllable within a certain range.

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