Variable rate DPSK system architecture
US6826371B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 15, 2000 |
| Grant date | Nov 30, 2004 |
| Priority date | — |
| Expiry date | Oct 22, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/18
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A communication system and more particularly to a variable rate differential phase shift keying (DPSK) communication system with minimal hardware that does not have power or performance penalties associated with known DPSK modulation systems is disclosed. The DPSK modulation system in accordance with the present invention includes a transmitter, which includes a carrier signal source, a phase modulator and a DPSK encoder for modulating a carrier signal. The modulated carrier signals may be amplified, for example, in optical communication systems by a rare earth element doped fiber amplifier. The signals are continuously transmitted to a multi-rate receiver through a communication channel, for example, free space. The multi-rate receiver includes a single demodulator, for example, a single optical interferometer, used for multiple integer sub-harmonic data rates which demodulates the modulated signal. The demodulated signals are detected, for example, in optical communication systems by an arrangement of photodiodes, and the detected signals are applied to, for example, a clock and data recovery circuit that is tuned as a function of data rate, for example, by way of a switched filt…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.