Constrained continuous phase modulation and demodulation in an optical communications system
US8983309B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 13, 2012 |
| Grant date | Mar 17, 2015 |
| Priority date | — |
| Expiry date | Jan 12, 2033 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B10/5561
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A transmitter in an optical communications system includes a digital signal processor for processing a data signal to generate a sample stream encoding successive symbols in accordance with a constrained phase modulation scheme having a constellation of at least two symbols and a modulation phase constrained to a phase range spanning less than 4π. A digital-to-analog converter converts the sample stream into a corresponding analog drive signal. A finite range phase modulator modulates a phase of a continuous wavelength channel light in accordance with the analog drive signal, to generate a modulated channel light for transmission through the optical communications system. A receiver in the optical communications system includes an optical stage for detecting phase and amplitude of the modulated channel light and for generating a corresponding sample stream, and a digital signal processor for processing the sample stream to estimate each successive symbol of the modulated channel light.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.