METHOD FOR IMPROVING THE RESOLUTION AND FOR CORRECTING DISTORTIONS IN A SIGMA-DELTA MODULATOR, AND SIGMA-DELTA MODULATOR IMPLEMENTING SAID METHOD

摘要

In a method for improving resolution and for correcting distortions for a sigma-delta modulator, a modulator converts an analog input signal into a secondary output digital signal sampled at a frequency f_e and coded on N_B bits, a second main output digital signal s′(t) is represented on N_MSB bits also being available at the output. At least three processings are applied successively to the outputs, a first processing carrying out a demodulation by a frequency f₀ and a decimation of factor N in an independent manner, z second processing carrying out an improvement of the resolution and a third processing carrying out a correction of the distortions. These three processings are carried out after decimation. A sigma-delta modulator implements the method.