Optical receiver particularly useful for a multi-wavelength receiver array
US6307660A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 21, 1998 |
| Grant date | Oct 23, 2001 |
| Priority date | — |
| Expiry date | Jan 21, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B10/6911
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A multi-wavelength optical receiver including multiple photodetectors receiving different ones of a multi-wavelength signal. For each wavelength-dedicated photodetector, a separate electronic receiver circuitry is provided including a current-to-voltage converting input transistor and an emitter-follower output transistor arranged as an operational amplifier with a feedback resistor. The circuit is improved by a cascode connection to the input transistor, by a reference to an analog ground rather than to a power supply line in both the photodiode and the cascode transistor, by the addition of capacitive shunts and a clamping transistor parallel to the feedback resistor in the feedback loop from the output transistor to the input transistor, by including positive and negative power supplies for the input and the output stages, by including multiple emitter followers in the output, by use of a differential second stage referenced to the analog ground, and by use of an output matching network that makes use of parasitic packaging inductances. Thereby, noise is reduce and inter-channel interference is minimized.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.