How do I design the mechanical structure of an RF system for minimum vibration-induced phase noise?

Designing the mechanical structure of an RF system for minimum vibration-induced phase noise (microphonics) prevents mechanical vibration from modulating the RF signal through physical displacement of components, cables, and circuit elements. Vibration-induced phase noise is critical in: radar systems (where phase noise limits the ability to detect slow-moving targets), communication systems (where phase noise degrades the modulation quality), and precision measurement systems (where phase stability determines the measurement accuracy). The mechanisms of vibration-induced phase noise are: cable flexing (a vibrating coaxial cable changes its electrical length as the cable bends, creating phase modulation. The sensitivity is 1-100 degrees/g depending on the cable type (standard flexible cables have high sensitivity; rigid and phase-stable cables have low sensitivity)), PCB flexing (the PCB bends under vibration, changing the trace length, component positions, and the dielectric thickness, all of which modulate the phase. Sensitivity: 0.1-10 degrees/g depending on the PCB construction and mounting), crystal oscillator and synthesizer (the quartz crystal in the reference oscillator is microphonic: mechanical stress changes the resonant frequency. Sensitivity: specified as the acceleration sensitivity (gamma) in Hz/g. Good OCXO: gamma approximately 1×10^-10 /g. Standard TCXO: gamma approximately 1×10^-9 /g). Mitigation techniques include: use rigid cables (semi-rigid or phase-stable cables instead of flexible cables; phase-stable cables have sensitivities 10-100× lower than standard flexible cables), stiffen the structure (increase the structural stiffness to raise the mechanical resonant frequencies above the vibration spectrum; use thick walls, ribs, and gussets; a structure with a first resonant frequency above 500 Hz is unaffected by most environmental vibration spectra), isolate the sensitive components (mount the oscillator, synthesizer, and sensitive receiver stages on vibration isolators (elastomeric mounts, wire rope isolators) that attenuate the vibration transmitted from the structure), and secure cables and components (use cable clamps at close intervals (every 50-100 mm for semi-rigid, every 100-200 mm for flexible cables) to prevent cable motion; use conformal coating or potting on sensitive PCB areas to stiffen the assembly).