Performance-oriented manufacturability analysis of a 5 GHz satellite oscillator

Modern communication and radar systems, especially if used for space or defense applications, need signal sources having high spectral purity and ultimate frequency stability. Most current and future designs must also include some way of frequency tuning. Digital synthesizers and multipliers are the conventional electronic solutions to these challenges, but unfortunately, they suffer from increased phase noise. The idea in the present survey was to study the feasibility and performance of fundamental frequency microwave dielectric resonator oscillators (DRO’s) as a substitute to frequency synthesis. If atomic frequency standards (such as cesium clocks or hydrogen masers) are excluded, all resonator-type oscillators (quartz crystals, dielectric resonators, surface acoustic wave devices) are of the mechanical vibration type. Dimensional tolerances and constructional rigidity issues, particularly in the resonator element itself, are thus of vital importance. The sharpness of the resonance curve defines the frequency accuracy to a certain extent, and therefore, we need the highest possible quality factor of the resonator, which calls for uncompromised surface quality. Usually, the electrical performance of this type of component is ensured with some computer-assisted tools before manufacturing the first prototype. This research showed that it is useful to simulate also the manufacturing stages beforehand to be able to find solutions for possible bottlenecks in the production. One of the key findings of the computer aided manufacturing (CAM) simulations was the importance of utilizing the optimum combination of the milling tool path, tool diameter, and the stepover to maximize the Q-value of the resonator but keeping the production at a reasonable level.