Multilevel pulse position modulation for efficient fiber optic communication
US7149256B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 29, 2002 |
| Grant date | Dec 12, 2006 |
| Priority date | — |
| Expiry date | Oct 20, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L25/4902
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
Decreasing the average transmitted power in an optical fiber communication channel using multilevel amplitude modulation in conjunction with Pulse Position Modulation (PPM). This multilevel PPM method does not entail any tradeoff between decreased power per channel and channel bandwidth, enabling a lower average transmitted power compared to On/Off Keying (OOK) with no reduction in aggregate data rate. Therefore, multilevel PPM can be used in high-speed Dense Wavelength Division Multiplexed (DWDM) systems where the maximum number of channels is traditionally limited by nonlinear effects such as self-phase modulation (SPM), cross-phase modulation (XPM), four-wave mixing (FWM), stimulated Brillouin scattering (SBS), and stimulated Raman scattering (SRS). This modulation technique can enable an increased number of channels in DWDM systems, thereby increasing aggregate data rates within those systems.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.