New methods for determining the number of effective bits of A/Dconverters based on eigendecomposition

摘要

For calculating the number of effective bits, we measure the rmsnoise by fitting the ADC's output signal to a curve. Thus, a nonlinearequation system is obtained and several Newton type iterative algorithmsare used to resolve it. We established that a good estimation of thefrequency for the first computation of an iterative process isnecessary. To remove this problem, we proposed new methods based on theeigendecomposition of the autocorrelation matrix in the input signal.The first, using the MUSIC method gives an accurate prime estimation ofthe frequency for the model which fits the output data. Then, this valueis introduced in a Newton type algorithm for a good estimation of thenoise. The second, more attractive, provides a direct accurateestimation of the noise. Condition testing and simulations will be givento validate these new methods