Strip dual mode ring resonator and band-pass filter composed of the resonators

摘要

A strip loop resonator, comprising:a loop-shaped strip line (153, 162) for resonating a microwave in a dual mode, the electric line length (θL=360 degrees) of the loop-shaped strip line being equivalent to a wavelength of the microwave to resonate the microwave circulated in the loop-shaped strip line according to an average line impedance of the loop-shaped strip line;an input strip line (152) for inputting the microwave to an input point of the loop-shaped strip line in electromagnetic coupling; andan output strip line (154) for outputting the microwave resonated in the loop-shaped strip line from an output point of the loop-shaped strip line in electromagnetic coupling,characterized in thatthe loop-shaped strip line comprises:a pair of coupling partial lines (153a; 153b, 162a; 162b) arranged in parallel to each other to couple the coupling partial lines of the loop-shaped strip line to each other in electromagnetic coupling, each of the coupling partial lines having an electric length θ1 (θ190 degrees) and a first line impedance Z1;a first side strip line of which both ends are connected to first side ends of the coupling partial lines, the first side strip line having an electric length θ2 (θ290 degrees) and a second line impedance Z2 different from the first line impedance Z1, the input and output points of the loop-shaped strip line being placed at the first side strip line, and the output point of the loop-shaped strip line being spaced a quarter of the wavelength of the microwave apart from the input point of the loop-shaped strip line; anda second side strip line of which both ends are connected to second side ends of the coupling partial lines, the second side strip line having an electric length θ3 (θ3 = 360 - 2*θ1 - θ2) and a third line impedance Z3 different from the first line impedance Z1.