Optical communication system
US6504636B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 10, 1999 |
| Grant date | Jan 7, 2003 |
| Priority date | — |
| Expiry date | Jun 10, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04J3/1694
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An optical communication system for optically transmitting transmission data from a transmitting station to a transmitting device includes an adder for adding an intermediate frequency subcarrier signal modulated with data to be transmitted to a pilot carrier signal as a sinusoidal wave, and an electro-optical converter for electro-optically converting the above sum signal to an optical signal by directly modulating a semiconductor laser element having a resonant frequency fr in accordance with the sum signal and transmitting the signal to an optical fiber for a down link. The frequency fIF of the intermediate frequency subcarrier signal and the frequency fLO of the pilot carrier signal satisfyfLO−fIF≧1 [GHz],2×fIF<fLO<(2/3)×fr,fIF<1 [GHz],and2 [GHz]<fLO.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.