Data compression apparatus and method for data recorder
US4906995A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 12, 1986 |
| Grant date | Mar 6, 1990 |
| Priority date | — |
| Expiry date | Dec 12, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M7/30
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A data compression method and apparatus particularly suitable for use in electrical power line fault data recorders. The system performs both gain compression and frequency compression. For gain compression, a predetermined number of samples are analyzed to determine a gain setting common to each sample in the set of samples. A reduced data string consisting of a gain code and data words having fewer bits than the input words are transmitted as a compressed data string. For frequency compression, a sample set representing the input signal is decimated until there remain only a sufficient number of data samples to satisfy the Nyquist criterion for the highest frequency component of interest. The frequency compressed output data string comprises a frequency code representing the highest frequency of interest followed by the set of decimated data samples.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.