A low phase noise oscillator based on substrate integrated coaxial line technology

Abstract

In this article, a miniaturized resonator based on substrate integrated coaxial line technology (SICL) is presented. The SICL resonator consists of a hairpin half-wavelength open-ended coaxial line element and two symmetrical parallel coaxial feed lines. The gap between the feed lines and the hairpin element can be adjusted properly to obtain a steep phase change, which can result in a higher group delay peak and achieve a superior phase noise performance. Based on the proposed SICL resonator, an X-band oscillator has been designed and demonstrated by using low-cost printed circuit boards (PCBs). Great consistency between the measured and simulated results is verified. According to the measured results, the oscillation frequency of the SICL oscillator is 10.0625\u2009GHz with −1.81\u2009dBm RF output power, and the phase noise is −138.6\u2009dBc/Hz@1\u2009MHz. The statistic figure of merit (FOM) is −206.1\u2009dBc/Hz@1\u2009MHz.