Title :
Error-driven edge selection for ΣΔ modulated signals to suppress in-band noise due to non-uniform sampling
Author :
Lee, Eel-Wan ; Chae, Soo-Ik
Author_Institution :
Dept. of Electr. Eng., Seoul Nat. Univ., South Korea
fDate :
4/2/1998 12:00:00 AM
Abstract :
A method for suppressing the in-band noise of ΣΔ-modulated signals due to non-uniform sampling is proposed. This method enables the use of the over-sampling clock generated from a fractional programmable generator without significant degradation in the signal-to-(noise+distortion) ratio (SNDR). The sampling frequency is controlled with a frequency resolution of 5.4 Hz without an analogue PLL. Experimental results for the voice band application of the ΣΔ-modulated 1 bit DAC show that the SNDR can be maintained at >70 dB, for sampling rates in the range 7.1-7.8 kHz
Keywords :
digital-analogue conversion; interference suppression; sigma-delta modulation; signal sampling; ΣΔ modulated signals; 7.1 to 7.8 kHz; SNDR; error-driven edge selection; fractional programmable generator; in-band noise suppression; nonuniform sampling; oversampling clock; sampling frequency control; voice band application;
Journal_Title :
Electronics Letters
DOI :
10.1049/el:19980466
