Phase monitor apparatus, phase control apparatus and methods thereof for optical DQPSK receiver
US7877025B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 7, 2006 |
| Grant date | Jan 25, 2011 |
| Priority date | — |
| Expiry date | Feb 12, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B10/677
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
I branch is provided with a first interferometer, a first balanced optical detector, and a first data recovery circuit. Q branch is provided with a second interferometer, a second balanced optical detector and a second data recovery circuit. In I branch, a mixer multiples input signal of the first data recovery circuit with output signal of the second recovery circuit. An averaging circuit averages output signal of the mixer. In Q branch, a mixer multiples input signal of the second data recovery circuit with output signal of the first recovery circuit. An averaging circuit averages output signal of the mixer. A first phase control apparatus controls the phase of a phase shifter comprised in the first interferometer based on the output signal of the averaging circuit. A second phase control apparatus, in the same manner, controls the phase of a phase shifter comprised in the second interferometer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.