Measurement system noise

Clean structural dynamic measurements are obtained when frequency response function maxima and minima fall within the dynamic range window of the measurement system. During a measurement process, attention is usually paid to maximum amplitudes and the prevention of overloads. Less attention is paid to sources of noise in the system that degrade minimum measurable levels. This is unfortunate because useful information about the structure is lost when the response function anti-resonances are truncated by an elevated noise floor. This paper considers how noise can affect measurements and offers a survey of noise floor measurements of various system components from several vendors.