Low phase noise oscillator based on quarter mode substrate integrated waveguide technique

Abstract

A low phase noise oscillator based on the quarter mode substrate integrated waveguide (QMSIW) technique is presented for the first time. The proposed oscillator is stabilized with the TE101 mode of a QMSIW resonator, which is 25% the size of the substrate integrated waveguide (SIW) resonator. In order to obtain a high loaded quality factor, the coupling coefficient between the QMSIW cavity and microstrip is tuned to be undercoupled. A X-band Prototype has been designed and fabricated. By using the QMSIW resonator, the fabricated oscillator has a more compact size than the SIW counterpart. The measured results show that the oscillator has a phase noise of −98.5 dBc/Hz at 100 kHz at 9.03 GHz, and an output power of 5.04dBm with a DC consumption of 20mW.