Patent ID: 6201458
Filing Date: 2001-03-13
Classification: H01P

Abstract:
A dual mode resonator for resonating two microwave signals, comprising:a one-wavelength loop-shaped strip line having a uniform line impedance for resonating a first microwave signal according to a first resonance mode and resonating a second microwave signal according to a second resonance mode orthogonal to the first resonance mode, electric voltage induced by the first microwave signal being maximized at a first coupling point A and a second coupling point B spaced 180 degrees in electric length apart from the first coupling point A, and electric voltage induced by the second microwave signal being maximized at a third coupling point C spaced 90 degrees in electric length apart from the first coupling point A and a fourth coupling point D spaced 180 degrees in electric length apart from the third coupling point C;a first open-end coupling strip line, placed in an inside area surrounded by the one-wavelength loop-shaped strip line, for electromagnetically influencing the first microwave signal;a second open-end coupling strip line, placed in the inside area of the one-wavelength loop-shaped strip line, for electromagnetically influencing the first microwave signal, electromagnetic characteristics of the second open-end coupling strip line being the same as those of the first open-end coupling strip line, the first and second open-end coupling strip lines being coupled to each other to form a capacitor having a distributed capacity, wherein the first and second open-end coupling strip lines are parallel to each other and open ends of the first and second open-end coupling strip lines are directed in the same direction;a first lead-in strip line for connecting the first open-end coupling strip line to the first coupling point A of the one-wavelength loop-shaped strip line to lead the first microwave signal in the first open-end coupling strip line; anda second lead-in strip line for connecting the second open-end coupling strip line to the second coupling point B of the one-wavelength loop-shaped strip line to lead the first microwave signal in the second open-end coupling strip line.