System and method for encoding ballast control signals
US8405488B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 20, 2009 |
| Grant date | Mar 26, 2013 |
| Priority date | — |
| Expiry date | Feb 24, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B47/199
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A system and method is provided for encoding and decoding control signals to an electronic ballast. An encoding circuit is effective to transmit encoded control signals across an AC power line comprising patterns of energy bursts at zero crossings of an AC signal. Eight zero crossings define a set, five specific patterns of energy bursts within a set define distinct symbols, each defined symbol selected such that a Hamming distance between each symbol is greater than three. Four symbols correspond to a first logic condition and one symbol corresponds to a second logic condition. Each received symbol is sequentially associated with a distinct control channel having one or more control parameters. A receiving circuit in the ballast is effective to decode symbols with single-bit error correction by comparing received symbols to defined symbols and determining which symbol is a smallest Hamming distance from a received symbol.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.