Optical offset signal cancellation for optical receiver
US7536107B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 30, 2004 |
| Grant date | May 19, 2009 |
| Priority date | — |
| Expiry date | Nov 3, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B10/66
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A laser driver for high speed interconnections may convert a digital signal to a current train of a bias mode to represent logical zero and of a modulation mode to represent logical one. An optical signal thus produced may include an optical offset. An optical receiver may include a photo-detector to receive the optical signal and generate a current signal, which includes a corresponding current offset. A first amplifier stage converts the current signal to a voltage signal and a second amplifier stage generates a digital output from the voltage signal. One or more low-pass filters may be used to filter the digital output and generate a filtered offset signal for a differential amplifier to generate an offset cancellation signal. The offset cancellation signal may be provided to offset cancellation circuitry to remove the current offset from the current signal generated by the photo-detector.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.