METHODS AND DEVICES FOR DETERMINING ROOT MEAN SQUARE OF A DELTA-SIGMA MODULATED SIGNAL

摘要

Described is a method and devices to determine root-mean-square of a delta- sigma modulated signal. The method includes filtering the delta-sigma modulated signal to produce a multi-bit filtered signal, delaying a copy of the delta-sigma modulated signal by a fixed number of samples to align with the filtered input, setting a sign of each multi-bit value of the multi-bit filtered signal based upon a corresponding sample value of the delayed copy of the delta-sigma modulated signal, to generate a hybrid signal, summing the hybrid signal to produce a summed signal, and determining the average of the summed signal and the square root of the average to produce a root-mean-square value.