Differential 90-degree Scheffman phase shifter based on slot line

Abstract

The present invention proposes a differential 90-degree Schiffman phase shifter based on a slot line, which is used to solve the technical problems of low common mode rejection and narrow phase shift bandwidth existing in the prior art. A pair of first U-shaped microstrip lines is printed on the upper surface of the first medium plate and a pair of first U-shaped microstrip lines is opposite to each other at the positions close to a set of opposite sides on the upper surface of the medium plate and the second medium plate, and the two pairs of first U-shaped microstrip lines are printed between them. A rectangular microstrip line is made, the metal floor on the upper surface of the second dielectric board is etched with a first composite slot line composed of an inverse C-shaped slot, a first rectangular slot and a first L-shaped slot as a reference line, and as a main line The second composite slot line, which is composed of a third rectangular slot, a second L-shaped slot, and a second rectangular slot linear slot, forms a microstrip-to-slot structure through the microstrip on the first dielectric plate and the gap on the second dielectric plate , to suppress common mode signals, and use the different phase shift characteristics of the main line and the reference line to achieve a stable phase shift.

Description

technical field [0001] The invention belongs to the field of microwave and radio frequency technology, and relates to a differential phase shifter, in particular to a slot line-based differential 90-degree Scheffman phase shifter, which can be applied to radio frequency microwave communication systems. Background technique [0002] The phase shifter is a key device that uses its ability to generate a relatively constant phase difference to achieve fast and accurate beams of phased array antennas or smart antenna systems. It consists of two parts, the main line and the reference line, and is used in the RF front-end circuit. Its performance is good Bad often directly affects the pros and cons of the entire communication system. There are many kinds of phase shifters, such as: Scheffman phase shifter, broadside coupling structure phase shifter, high / low pass network phase shifter, etc. Among them, the Scheffman phase shifter consists of an ordinary uniform transmission line A...

AI Technical Summary

Problems solved by technology

Among them, the ladder impedance of the center load is used to achieve common mode rejection, and the quarter-wavelength coupling line and two quarter-wavelength branch lines are used to reduce the phase shift error. The whole structure achieves a relatively stable phase shift amount, but due to Its entire design is all implemented by microstrip, resulting in its low common-mode rejection and narrow phase-shift bandwidth

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