Research and Design of a Low Phase-Noise Dielectric Resonator Oscillator for X-Band Radar Applications

This paper presents the research, design, and implementation of a low phase-noise dielectric resonator oscillator (DRO) operating at 9.4 GHz for X-band radar applications. A high-quality-factor dielectric resonator operating in the mode was employed to enhance frequency stability and suppress phase noise. The oscillator was realized using a microstrip coupling structure, with a GaAs FET transistor serving as the active element in the feedback network. Comprehensive electromagnetic and circuit-level simulations were conducted in CST and ADS to optimize the resonator coupling and feedback configuration, ensuring stable oscillation and effectively mitigating spurious modes. Compared with conventional oscillator designs, the proposed DRO demonstrates superior frequency stability and reduced phase noise, while maintaining a compact form factor. These characteristics render the proposed design highly suitable for modern X-band radar front-ends as well as other advanced microwave communication systems requiring low-noise and high-stability local oscillators.