Method of sampling, downconverting, and digitizing a bandpass signal using a digital predictive coder
US6002352A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 24, 1997 |
| Grant date | Dec 14, 1999 |
| Priority date | — |
| Expiry date | Jun 24, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M1/208
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A simple down converting A/D converter utilizing predictive coding principles. By placing the sampler inside the predictive loop, the predictive loop filter can be implemented using DSP techniques, thus eliminating the complexities introduced by use of discrete-time analog circuitry. Then, by re-mapping the output of the predictive loop filter into the analog domain using a D/A converter, the predictive filter output signal is subtracted from the input analog signal to generate the prediction error signal. Therefore, through directly sampling the prediction error signal and converting the output of the predictive loop filter into analog representation using a low-cost multiple bit D/A, the use of discrete-time analog circuitry is eliminated and the complexity of the converter design is greatly reduced. Various features of the invention are disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.