Title :
A 2-path bandpass sigma-delta modulator utilizing a 3-path structure
Author :
Moule, Eric C. ; Ignjatovic, Zeljko
Author_Institution :
Dept. of Electr. & Comput. Eng., Rochester Univ., NY, USA
Abstract :
We present a two-path bandpass sigma-delta (ΣΔ) modulator design that improves upon current designs by completely suppressing the mirror image in the input signal band. The proposed structure introduces a modulator consisting of three paths utilized in a periodic manner, which serves to relocate the mirror image caused from path mismatch far from the signal band of interest. A specific example of a pseudo-two-path modulator utilizing a modulator based on a pseudo-three-path structure is described. This design is shown to improve the SFDR by 25dB from previous two-path techniques.
Keywords :
band-pass filters; network synthesis; sigma-delta modulation; ΣΔ modulator design; SFDR; input signal band mirror image suppression; mirror image relocation; path mismatch; periodic modulator paths; pseudo-three-path structure; pseudo-two-path modulator; signal band; three-path structure; two-path bandpass sigma-delta modulator; two-path techniques; CMOS technology; Delta-sigma modulation; Frequency; Image sampling; Mirrors; Noise reduction; Noise shaping; Operational amplifiers; Periodic structures; Signal design;
Conference_Titel :
Circuits and Systems, 2005. ISCAS 2005. IEEE International Symposium on
Print_ISBN :
0-7803-8834-8
DOI :
10.1109/ISCAS.2005.1465424
