System and method for code division multiplexed optical communication
US7167651B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 26, 2001 |
| Grant date | Jan 23, 2007 |
| Priority date | — |
| Expiry date | Jul 11, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B10/508
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A system for optical communication forms a family of orthogonal optical codes modulated by a data stream. The orthogonal codes are formed by creating a stream of evenly spaced-apart pulses using a pulse spreader circuit and modulating the pulses in amplitude and/or phase to form a family of orthogonal optical code words, each representing a symbol. A spreader calibration circuit is used to ensure accurate timing and modulation. Each code word is further modulated by a predetermined number of data bits. The data modulation scheme splits a code word into H and V components, and further processes the components prior to modulation with data, followed by recombining with a polarization beam combiner. The data-modulated code word is then sent, along with others to receiver. The received signal is detected and demodulated with the help of a symbol synchronization unit which establishes the beginning and end of the code words. A polarization mode distortion compensator at the receiver cooperates with a state of polarization compensator at the transmitter to mitigate polarization distortion in the fiber.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.