Title :
Direct-conversion bandpass sigma-delta modulator
Author :
Tao, Hai ; Khoury, J.M.
Author_Institution :
Dept. of Electr. Eng., Columbia Univ., New York, NY, USA
fDate :
7/17/1997 12:00:00 AM
Abstract :
A bandpass sigma-delta modulation analogue-to-digital (A/D) converter that uses direct conversion to baseband with in phase and quadrature paths within the feedback loop is described. The bandpass input signal is processed with continuous-time circuitry and the I/Q baseband signals are processed with switched-capacitor circuits. Experimental and simulation results indicate that the passband centre frequency can be maximised while suppressing the effects of I/Q mismatches
Keywords :
circuit feedback; modulators; sigma-delta modulation; A/D converter; ADC; I/Q baseband signals; analogue-to-digital converter; continuous-time circuitry; direct-conversion bandpass type; feedback loop; sigma-delta modulator; switched-capacitor circuits;
Journal_Title :
Electronics Letters
DOI :
10.1049/el:19970888
