Patent · US Expired

D/A converter noise reduction system

US5594443A · kind A · utility

10Cited by
2References
51Claims
0Family size

Inventor

Key dates

Filing dateApr 28, 1994
Grant dateJan 14, 1997
Priority date
Expiry dateApr 28, 2014

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03M1/68
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

An apparatus for improving the quality of an analog signal reproduced from digital samples by limiting the amount of sampling and quantization noise present within reproduced analog signals. The apparatus is comprised of a D/A converter coupled to an interpolator processing original digital samples operating at a reproduction rate greater than the original sampling frequency and at a digital resolution greater than or equal to the original digital samples to generate digital pseudo-samples. The processed digital pseudo-samples are then provided to the D/A converter at the reproduction rate. As a consequence of the increase in the reproduction rate, sampling noise is moved further away in the frequency domain from the original analog signal, thus eliminating or reducing the requirement for a low-pass filter. Due to the increased number of samples and the increased digital resolution of the samples, the reproduction errors are further minimized.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.