Chamber Geometry
Cavity resonance drives the electromagnetic evaluation inside a reverberation chamber during board level RF immunity testing. High quality factor modes establish statistical field uniformity when mechanical paddle stirrers rotate continuously throughout the procedure. Internal wall boundaries reflect microwaves without absorption, creating a densely populated multipath environment.
Mode tuning algorithms calculate frequency steps based on cavity volume dimensions to prevent modal overlap failures during automated sweeps. Electric field probes measure local maxima variations to verify compliance with military standards before a production lot enters final packaging.
Paddle Rotation
Stirrer mechanics distribute wave polarization states randomly across the Device Under Test during immunity verification runs. Stepper motors rotate metallic vanes in discrete increments to alter boundary conditions inside the shielded enclosure. Continuous agitation prevents standing wave nulls from shielding susceptible circuit traces from high intensity interference signals.
Signal generators synchronize RF amplification levels with paddle positioning data to maintain calibrated stress thresholds at every frequency step.
Field Calibration
Spatial uniformity requirements dictate placement criteria for sensor arrays positioned around the printed circuit board assembly under evaluation. Statistical analysis software processes multiple field strength readings to validate standard deviation limits across the entire working volume. Normalized amplitude values establish baseline immunity margins before operational software executes automated susceptibility routines.
Calibration logs record maximum deviation figures from planar probes to determine measurement uncertainty budgets for commercial compliance reports.
