Line-oriented spectrum evaluation for sensor SNR estimation

When the dynamic performance of sensors has to be evaluated, the signal-to-noise ratio (SNR) is a useful figure of merit. A method for estimating the SNR of an analog sensor is proposed by which the sensor is stimulated sinusoidally, and its output sampled. It is then subjected to a digital Fourier Transform (DFT), and the resulting spectrum analyzed to obtain the sensor's SNR value. This line-oriented evaluation scheme provides detailed information on the sensor output. A low-noise experimental setup for coherently testing displacement sensors is also described.