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.