Extrema coder employing noisy limiting amplifier stages
US4819199A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 24, 1987 |
| Grant date | Apr 4, 1989 |
| Priority date | — |
| Expiry date | Apr 24, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B1/66
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An extrema coding circuit comprising a differentiator and a noisy limiting-amplifier. The limiting-amplifier may comprise any one of a number of commercially available limiting-amplifier integrated circuits, for example, a limiting-amplifier front end of an FM IF amplifier and detector integrated circuit. The limiting-amplifier is operated so that the input voltages provided to it are in the order of magnitude of broadband noise generated internally by the limiting-amplifier stages. Accordingly, the limiting-amplifier stages encode the differentiated analog signal and the internally generated noise signal into an extrema coded signal, i.e., a signal wherein the times of occurrence of extrema are represented as transitions of a binary signal. Because of the high gain of the limiting-amplifier stages, these stages perform infinite clipping. The extrema coded signal contains information sufficient to enable substantial reproduction of the original analog signal therefrom. In order to reproduce the input analog signal, the extrema coded signal may be fed to an integrating stage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.