A microstrip combiner with uniform impedance stub loading

Abstract

The microstrip combiner with uniform impedance stub loading of the present invention includes a low-pass filter circuit, a high-pass filter circuit and a combiner circuit, and is characterized in that the low-pass filter circuit includes two cascaded π1-type structural units, and the π1-type structural unit It has a main transmission line and two uniform impedance open-circuit stubs arranged at both ends of the main transmission line. The pole of the π1-type structural unit is located on the left side of its two zeros; the high-pass filter circuit contains two cascaded π2-type structural units, and the π2-type structural unit With a main transmission line and two uniform impedance open-circuit stubs arranged at both ends of the main transmission line, the pole of the π2-type structural unit is located between its two zero points. The beneficial effects of the present invention are as follows: by adjusting the parameter value of the structural unit, the position of the zero-pole point can be flexibly adjusted, thereby producing good roll-off characteristics; the use of non-equal-length stub loading in the design can reduce the size of the circuit, making the circuit simpler lightweight.

Description

technical field [0001] The invention relates to the technical field of combiners, in particular to a microstrip combiner loaded with uniform impedance stubs. Background technique [0002] At present, the known microstrip combiners loaded with open stubs of radio frequency signals have mostly the same width as the stubs and the main line, and the wiring area is relatively large, which is not suitable for the miniaturization of combiners in the base stations of most mobile communication systems. , based on this, a miniaturized microstrip combiner loaded with unequal-length open stubs is proposed. [0003] After searching, it is found that the patent CN 204348876 U discloses a built-in microstrip combiner for an ultra-wideband dual-frequency dual-polarization base station antenna, including high-frequency branching, low-frequency branching and high-low frequency combining. The high-frequency branching has two Open stubs, the low frequency shunt has three open stubs. The micro...

AI Technical Summary

Problems solved by technology

However, its disadvantages are: the branch adopts step impedance transformation line segment, the design is relatively complicated; the length difference of the main line between the branches is very small, and the purpose of further reducing the circuit volume cannot be achieved.

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