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Title: Fade-resistant forward error correction method for free-space optical communications systems

Abstract

Free-space optical (FSO) laser communication systems offer exceptionally wide-bandwidth, secure connections between platforms that cannot other wise be connected via physical means such as optical fiber or cable. However, FSO links are subject to strong channel fading due to atmospheric turbulence and beam pointing errors, limiting practical performance and reliability. We have developed a fade-tolerant architecture based on forward error correcting codes (FECs) combined with delayed, redundant, sub-channels. This redundancy is made feasible though dense wavelength division multiplexing (WDM) and/or high-order M-ary modulation. Experiments and simulations show that error-free communications is feasible even when faced with fades that are tens of milliseconds long. We describe plans for practical implementation of a complete system operating at 2.5 Gbps.

Inventors:
 [1];  [2];  [1]
  1. Livermore, CA
  2. Castro Valley, CA
Issue Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
917189
Patent Number(s):
7277644
Application Number:
10/676,450
Assignee:
The Regents of the University of California (Oakland, CA)
Patent Classifications (CPCs):
H - ELECTRICITY H03 - BASIC ELECTRONIC CIRCUITRY H03M - CODING
H - ELECTRICITY H04 - ELECTRIC COMMUNICATION TECHNIQUE H04J - MULTIPLEX COMMUNICATION
DOE Contract Number:  
W-7405-ENG-48
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
47 OTHER INSTRUMENTATION

Citation Formats

Johnson, Gary W, Dowla, Farid U, and Ruggiero, Anthony J. Fade-resistant forward error correction method for free-space optical communications systems. United States: N. p., 2007. Web.
Johnson, Gary W, Dowla, Farid U, & Ruggiero, Anthony J. Fade-resistant forward error correction method for free-space optical communications systems. United States.
Johnson, Gary W, Dowla, Farid U, and Ruggiero, Anthony J. Tue . "Fade-resistant forward error correction method for free-space optical communications systems". United States. https://www.osti.gov/servlets/purl/917189.
@article{osti_917189,
title = {Fade-resistant forward error correction method for free-space optical communications systems},
author = {Johnson, Gary W and Dowla, Farid U and Ruggiero, Anthony J},
abstractNote = {Free-space optical (FSO) laser communication systems offer exceptionally wide-bandwidth, secure connections between platforms that cannot other wise be connected via physical means such as optical fiber or cable. However, FSO links are subject to strong channel fading due to atmospheric turbulence and beam pointing errors, limiting practical performance and reliability. We have developed a fade-tolerant architecture based on forward error correcting codes (FECs) combined with delayed, redundant, sub-channels. This redundancy is made feasible though dense wavelength division multiplexing (WDM) and/or high-order M-ary modulation. Experiments and simulations show that error-free communications is feasible even when faced with fades that are tens of milliseconds long. We describe plans for practical implementation of a complete system operating at 2.5 Gbps.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {2007},
month = {10}
}

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