Wavelength division multiplexed passive optical network
US8023824B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 5, 2008 |
| Grant date | Sep 20, 2011 |
| Priority date | — |
| Expiry date | Feb 28, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04J14/0282
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
Data is transmitted between a central office and customer premises by a wavelength division multiplex passive optical network. Two laser beams with separate wavelengths are transmitted from the central office to an optical network unit in the customer premises. Both laser beams carry downstream data. One laser beam is intensity modulated by on/off keying. The other laser beam is phase modulated by differential phase shift keying, which maintains a constant optical intensity. The first laser beam is received by a first optical receiver, which demodulates the first downstream data. The second laser beam is split in two. One laser beam is sent to a second optical receiver, which demodulates the second downstream data. The other laser beam is sent to a reflective semiconductor amplifier, which modulates the beam with upstream data and transmits the beam back to a receiver in the central optical system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.