Over-equalization for multi-span wavelength division multiplexed fiber optic communication systems
US6701089B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 30, 2000 |
| Grant date | Mar 2, 2004 |
| Priority date | — |
| Expiry date | Oct 22, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04J14/02216
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
In an amplified wavelength division multiplexes (WDM) fiber optic communication system, each channel experiences a different optical gain, dispersion and noise. Also, the evolution of WDM fiber optic systems to higher density channel spacing has further aggravated multi-channel non-linear distortions such as four-wave mixing (FWM) and cross-phase modulation (XPM). The standard method for controlling these nonlinearities is the peak power control method. The performance of the channels can be equalized by adjusting the transmission powers of the optical transmitters. However, just equalization of a performance indication factor (PIF) such as BER or Q is not the optimum approach when peak power control mode of operation dominates. This invention is directed towards improving the margins of performance of WDM fiber optic channels. The transmission powers of the channels are adjusted methodically until the received performance margins of the channels are substantially equal then the power levels of the channels under peak power control mode are increased to just touch the provisional power level.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.