Experimental characterization of microphonics in RF cavities using affordable RF instrumentation

This study investigates vibration-induced detuning in a simplified room-temperature RF cavity using lowcost software-defined radio instrumentation. Progressive frequency sweeps under shaker-OFF and shaker- ON conditions were used to estimate resonance shifts, while fixed-frequency single-tone measurements near resonance captured vibration-induced amplitude and phase variations. Comparison with vector network analyser data showed that the SDR reproduced the main spectral features despite its uncalibrated response. A preliminary multiphysics finite-element model predicted resonance-frequency shifts of the same order of magnitude as the experimental estimates. Although preliminary, the results support the feasibility of affordable SDR-based instrumentation for initial studies of vibration-induced RF detuning and provide a first step towards an experimental–numerical framework for future digital-twin validation of RF cavities.