Method and apparatus for using on-off-keying using laser relaxation oscillation
US5808770A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 29, 1995 |
| Grant date | Sep 15, 1998 |
| Priority date | — |
| Expiry date | Dec 29, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B10/504
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An optical communications system for transmission of optical signals using relaxation oscillation subcarrier, on-off keying modulation of the optical signals. Relaxation oscillation subcarrier on-off keying improves the signal-to-noise ratio of a receiver receiving the modulated optical signals and the data rate of the optical signal. A modulation device generates relaxation oscillations by pulsing a driving current for a transmitter between a first level below a threshold current and a second level above the threshold current. The optical communication system can further include a fiber optic link between the transmitter and the receiver. The optical communications system can further incorporate multiple frequency shift keying. The modulation device and modulation scheme can be used in all digital optical communications systems using a pulsed laser diode.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.