Apparatus and method for measuring optical signal-to-noise ratio
US6671045B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 5, 2000 |
| Grant date | Dec 30, 2003 |
| Priority date | — |
| Expiry date | Oct 19, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J4/04
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An apparatus and method for measuring optical signal-to-noise ratio in optical communications includes (1) a variable optical band-pass filter (VOBPF) that passes the amplified output beam when the beam wavelength is the same as the passing wavelength of the VOBPF; (2) a 1×4 beam distributor for distributing the passing beam of the VOBPF into four streams; (3) a measuring device for measuring Stokes parameters S0, S1, S2, S3 from the four distributed beams; (4) a calculating device for calculating the optical signal power by finding the power of the polarized component of the amplified output beam from the Stokes parameters S1, S2, and S3; (5) a calculating device for calculating the noise power by finding the power of the noise included in the amplified output beam from Stokes parameter S0 and the optical signal power; and (6) a dividing device for calculating the ratio at the passing wavelength.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.