A low phase noise oscillator using spur line resonator for I-band application

This paper presents a compact size microstrip spur line resonator and its application to a low phase noise oscillator of 9.2 GHz. This resonator has bandstop characteristic to be used in the series feedback oscillator topology. A miniaturized spur line resonator consists of a defected spur line with inductive characteristics and a loaded stub with capacitive characteristics. The structure can reduce the space of the circuit area as well as cost. The oscillator with this resonator shows an excellent phase noise performance of -96.23 dBc/Hz at 100 kHz offset with output power of 14.47 dBm.