Patent · US Expired

Analog to digital conversion system utilizing dither

US4914439A · kind A · utility

32Cited by
5References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 9, 1988
Grant dateApr 3, 1990
Priority date
Expiry dateSep 9, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03M1/0641
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A system suitable for digitizing an analog audio signal, with the addition of analog dither to the audio signal and, after the digitization of the resulting analog audio/dither signal, the subtraction of digital dither from the digital audio/dither signal. For the production of the analog and digital dither signals, a digital dither generator is employed which generates digital dither of, e.g., 16 bits. The analog dither signal is derived from this 16 bits dither by first translating the same into analog dither of equivalent magnitude and then by reducing its magnitude to a value equivalent to e.g., 10 bits. The digital dither signal, on the other hand, is provided by reducing the magnitude of the 16 bits digital dither to that of substantially 10 bits. The analog dither signal is added to the audio signal, and the resulting analog audio/dither signal is translated by an analog to digital converter of, e.g., 16 bits into a digital audio/dither signal. Then the substantially 10 bits digital dither signal is subtracted from the digital audio/dither signal. A limiter may be connected to the output of the subtracter for limiting the output level when the analog to digital converter is …

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