Noise statistics of ratiometric signal processing systems
Donald J. Svetkoff, Thomas G. Xydis, Donald B. Kilgus · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1991
Signal processing systems used for color measurement laser range finding or background subtraction often compute the value of a parameter of interest by division of signals obtained from multiple sensor channels. Although the noise statistics of a single channel may often be accurately modeled as a linear transformation of a Gaussian random process the computation of a ratio constitutes a nonlinear estimation problem which may be particularly difficult to analyze in closed form. This paper demonstrates the use of a computational based model for estimating the output distribution and statistics of a ratiometric processing system. Examples will show the error performance of the signal processor with decreasing input signal to noise ratio the overall result being a bias in the estimate in addition to the expected increase in the sample variance. Extension of the analysis approach to other nonlinear systems will also be discussed.