Departmental Papers (ESE)


This article briefly describes conventional A/D conversion, as well as its performance modeling. We then look at the technique of oversampling, which can be used to improve the resolution of classical A/D methods. We discuss how sigma-delta converters use the technique of noise shaping in addition to oversampling to allow high resolution conversion of relatively low bandwidth signals. Next, we examine the use of sigma-delta converters to convert narrowband bandpass signals with high resolution. Several parallel sigma-delta converters, which offer the potential of extending high resolution conversion to signals with higher bandwidths, are also described.

Document Type

Journal Article

Date of this Version



Copyright 1996 IEEE. Reprinted from IEEE Signal Processing Magazine, Volume 13, Issue 1, September 1996, pages 61-84.

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analog to digital converter, adc, sigma-delta conveter, sigma-delta modulator, sampling, quantization



Date Posted: 11 August 2005

This document has been peer reviewed.