Patent Document ID: 5408235
Application ID: 08207040
Patent Flag: 1

Claim One:
1. An oversampling analog to digital converter, for converting an input signal having a baseband frequency into an output set of high resolution samples having an output frequency and representing said input signal, comprising: (a) a Sigma-Delta modulator for (i) receiving, from a clock pulse generator, an oversampling clock signal having an oversampling frequency, (ii) receiving said input signal, and (iii) sampling said input signal at said oversampling frequency and producing a first set of coarsely quantized samples having said oversampling frequency and representing said input signal, wherein said oversampling attenuates quantization noise in the frequency range from DC to said basedband frequency while increasing quantization noise for frequencies greater than said baseband frequency; and (b) a digital filter for (i) receiving said oversampling clock signal, (ii) receiving said first set of samples from said modulator, and (iii) computing a first weighted average of an adjustable number of samples in said first set of samples, and thereby producing a second set of samples representing said input signal and having a second sampling frequency equal to said oversampling frequency divided by said adjustable number of samples used in computing said first weighted average, wherein said weighted averaging attenuates quantization noise for frequencies greater than said baseband frequency.