A reconfigurable substrate-integrated waveguide bandpass filter and its reconfigurable method

Abstract

The invention discloses a reconfigurable substrate integrated waveguide bandpass filter and a reconfigurable method of the filter and mainly solves technical problems that the tuning range is small, the insertion loss of reconfigurable substrate integrated waveguide bandpass filters is high and control voltage of variable capacitance diodes cannot be directly applied to substrate integrated waveguides. One variable capacitance diode is placed in a non-metal via hole formed in the center of each of two complementary split-ring resonators of the bandpass filter, the metal part at an inner ring opening of each complementary split-ring resonator is replaced with a blocking capacitor, so that a substrate integrated waveguide is separated from an outer circuit, and a voltage source is prevented from being short-circuited; the variable capacitance diodes are connected with a direct-current bias circuit, reversed bias voltage at two ends of the variable capacitance diodes is adjusted, junction capacity of the variable capacitance diodes is changed, so that the resonant frequency of the two complementary split-ring resonators is affected, and the passband center frequency is reconfigurable. The feeding manner of the variable capacitance diodes in the substrate integrated waveguide is realized, the control manner is simple and easy to implement, the frequency tuning range is relatively large, the in-band insertion loss is low, and the filter can be applied to a wireless communication system.

Description

technical field [0001] The invention belongs to the technical field of electronic devices, in particular to a substrate-integrated waveguide bandpass filter, in particular to a reconfigurable substrate-integrated waveguide bandpass filter and a reconfigurable method thereof, which are used for the radio frequency front end of a wireless communication system. Background technique [0002] With the development and innovation of modern wireless communication systems, microwave and millimeter-wave systems are rapidly developing towards miniaturization, high integration, and low cost. The waveguide structure with low loss, high quality factor and high power capacity has been widely used due to its excellent performance, but its size and volume are too large to be suitable for applications with high miniaturization and high integration; while traditional microstrip Although the structure has large radiation, due to its small size and simple processing, it can meet the volume and i...

AI Technical Summary

Problems solved by technology

[0006] At present, there are relatively few reconfigurable substrate-integrated waveguide bandpass filters based on varactor diodes. The reason is that the metal pillars on one side of the substrate-integrated waveguide directly connect the ground plate and the upper surface of the substrate-integrated waveguide. The control voltage of the diode cannot be directly added to the substrate integrated waveguide

The existing method is to connect the varactor diode between the resonant ring and the metal floating capacitor, and realize the adjustment and control of the resonant ring capacitance through the capacitive effect of the metal floating capacitor. The control structure is complex and the filter insertion loss is large, and the adjustable range is small.

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