JPS6474807A - Strip line resonator for vco - Google Patents

Abstract

PURPOSE:To hold the QL value of a strip line resonator at a high level, by setting coupling with an oscillating transistor and the coupling with a variable capacitive diode in the neighborhood of the current short-circuiting point of a strip line. CONSTITUTION:The strip line 3 is the strip line resonator with line length of lambdag/2 provided on a dielectric substrate 60, and the both ends of the line form the open end of a standing wave, and the center of the line becomes a short-circuiting point. And the coupling with the oscillating transistor Tr1 of the line 3 is performed by cutting a tap 4 and connecting it to the optimum position in the neighborhood of the center of the line by a bonding ribbon 6. Also, the coupling with the variable capacitive diode 2 is performed by cutting a tap 5 and connecting it to the optimum position in the neighborhood of the short-circuiting point in the center of the line similarly by the ribbon 6. Since the short-circuiting point of the standing wave is not formed by a capacitor in the resonator constituted in such way, it is possible to realize loose coupling setting at the optimum position easily by using the ribbon 6 without using a bonding wire, thereby, the QL value can be maintained at a high value.