Quantization noise reduction in oversampled analog-to-digital signal conversion
US5493297A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 29, 1994 |
| Grant date | Feb 20, 1996 |
| Priority date | — |
| Expiry date | Dec 29, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M3/454
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Quantization noise in oversampled digital data can be reduced by processing including alternate steps of lowpass filtering and so-called code projection, in cases where the set of discrete-time signals corresponding to quantized-signal data is a convex set. Corresponding specific methods are disclosed for simple analog-to-digital conversion, "dithered" analog-to-digital conversion, and first- and second-order single-path .SIGMA..DELTA.-conversion. For example, in the case of simple analog-to-digital conversion, code projection involves replacing sample values by quantization-threshold values in those cases where, after filtering, a sample value lies in a different quantization interval as compared with the corresponding value of quantized-signal data.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.