Design of Ku-band Low Phase Noise Oscillator Utilizing High-Q Air-filled Substrate Integrated Waveguide Resonator

In this paper, a high-Q factor air-filled substrate integrated waveguide (AFSIW) resonator is firstly applied to the design of Ku-band low phase noise planar oscillator. The AFSIW resonator utilizes air-filled substrate to replace the dielectric-filled substrate. It can reduce loss, and realize higher quality factor than the conventional substrate integrated waveguide(SIW) resonator. The air-filled part of the AFSIW is covered by two metallic covers or two plated substrates, which can be integrated with other planar circuits and active devices easily. Therefore, taking the proposed AFSIW resonator as frequency stabilization element, microwave planar oscillator can realize excellent phase noise performance. To validate the proposed method, a Ku-band low phase noise planar oscillator based on AFSIW is firstly designed and measured. The results show that the oscillator operates at 14.84GHz with -5.9dBm output power. The measured phase noise and the calculated figure of merit(FOM) of the oscillator are -128.3dBc/Hz and -198.7dBc/Hz at 1MHz offset carrier frequency, respectively.