Regeneration of optical phase modulated signals
US7369779B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 14, 2005 |
| Grant date | May 6, 2008 |
| Priority date | — |
| Expiry date | Jun 28, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B10/299
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A regenerator for restoring the originally encoded optical phase of a differential-phase-shift-keyed signal. In an embodiment, the regenerator simultaneously provides limiting amplification and reduces amplitude noise based on a phase-sensitive optical amplifier that combines a weak signal field of a degraded input data with a strong pump field supplied by a local oscillator in a nonlinear interferometer. The two fields interact through degenerate four-wave mixing, and optical energy is transferred from the pump to the signal and vice versa. The phase sensitive nature of the optical gain leads to amplification of a specific phase component of the signal, determined by the input pump-signal phase difference and the incident signal phase is restored to two distinct states, separated by 180° according to the original encoding. Simultaneously, gain saturation of the pump wave by the signal wave results in limiting amplification of the signal wave for removing signal amplitude noise.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.