Coherent photonic telecommunications system
US4745592A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 28, 1987 |
| Grant date | May 17, 1988 |
| Priority date | — |
| Expiry date | Jan 28, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04Q11/0001
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
The system comprises subscriber stations (1, 2) each comprising a semiconductor laser generator (4) provided with means (3, 5) for modulating its laser output by means of transmit signals and a heterodyned detection system consisting of a photoelectric receiver (15) optically coupled to a local oscillator (17), an exchange (32) comprising a computer (37) and dual cavity semiconductor laser transmitters (39) connected to the outputs (38) of the computer, a passive optical distributor (31), and optical fibers (16, 8) connecting the lasers (4) and receivers (15) of each station with the optical distributor (31), on the one hand, and the lasers (4) of each station to the exchange (32), on the other hand, the computer assigning an optical frequency for each requested call and the laser transmitters of the exchange being operable to lock the transmit optical frequency of the calling and the called station lasers (4, 104), via optical fiber lines (8), on the frequency assigned by the computer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.