Hybrid Balun filter

Abstract

The invention discloses a hybrid Balun filter. The hybrid Balun filter comprises a metal ground plate, a metal enclosure, a coaxial resonator, a first dielectric resonator and a second dielectric resonator, wherein the dominant mode frequencies of the coaxial resonator, the first dielectric resonator and the second dielectric resonator are identical; a first metal separation plate with a coupling window is arranged between the first dielectric resonator and the coaxial resonator; a second metal separation plate with a coupling window is arranged between the second dielectric resonator and the coaxial resonator; the first dielectric resonator and the second dielectric resonator are totally identical and are symmetrically distributed at two sides of the coaxial resonator; the axes of the first dielectric resonator and the second dielectric resonator are perpendicular to the metal ground plate; and the axis of the coaxial resonator is parallel to the metal ground plate. According to the hybrid Balun filter provided by the embodiments of the present invention, the coaxial resonator and the dielectric resonators are combined, so that most parasitic modes of the dielectric resonators can be suppressed, and therefore, the Balun filter is wider in differential-mode stop band, lower in insertion loss, and good in output balance.

Description

technical field [0001] The invention relates to the field of radio frequency communication, in particular to a hybrid balun filter. Background technique [0002] Baluns and filters play an important role in RF front-end modules. For a long time, the two existed independently in the RF front-end module. However, this would result in an excessively large circuit size and increased losses. In the past few decades, the fusion design method of the balun filter has been widely studied and used to reduce the size of the entire circuit and reduce the circuit loss. The fusion-designed balun filter can not only have the band selection characteristics of the filter but also have the conversion function of the balun unbalanced to balanced signal. [0003] Dielectric resonators are widely used in microwave circuit design, including balun filter design, due to their high quality factor, low manufacturing cost, and high temperature stability. However, the biggest disadvantage of dielec...

AI Technical Summary

Problems solved by technology

[0004] The technical problem to be solved by the embodiments of the present invention is to provide a hybrid balun filter to overcome the defect of insufficient stop-band suppression performance of the balun filter in the prior art

Images