dcsimg
Main » TERM » E »

EDFA - erbium-doped fiber amplifier

Erbium-doped fiber amplifier (EDFA) is an optical repeater device that is used to boost the intensity of optical signals being carried through a fiber optic communications system.

How it Works

An optical fiber is doped with the rare earth element erbium so that the glass fiber can absorb light at one frequency and emit light at another frequency. An external semiconductor laser couples light into the fiber at infrared wavelengths of either 980 or 1480 nanometers. This action excites the erbium atoms. Additional optical signals at wavelengths between 1530 and 1620 nanometers enter the fiber and stimulate the excited erbium atoms to emit photons at the same wavelength as the incoming signal. This action amplifies a weak optical signal to a higher power, effecting a boost in the signal strength.

Fiber optic use in the 1980s required the light signals to be converted back into electronic signals at the data's final destination. EDFA removes this step from the process: all the steps of its operation are the actions of photons, so there is no conversion of optical signals to electronic signals.

Erbium had little commercial uses before the age of fiber-optic telecommunications. Now it is an important constituent of signal repeaters in long-distance telephone cables.










LATEST ARTICLES
Facts about IT & Coding Boot Camps

The following coding and IT boot camp facts and statistics provide an introduction to the changing trends in education and training programs. Read More »

Top Cloud Computing Facts

The following facts and statistics capture the changing landscape of cloud computing and how service providers and customers are keeping up with... Read More »

Texting & Chat Abbreviations

From A3 to ZZZ this guide lists 1,500 text message and online chat abbreviations to help you translate and understand today's texting lingo. Read More »

STUDY GUIDES
Java Basics, Part 1

Java is a high-level programming language. This guide describes the basics of Java, providing an overview of syntax, variables, data types and... Read More »

Java Basics, Part 2

This second Study Guide describes the basics of Java, providing an overview of operators, modifiers and control Structures. Read More »

Network Fundamentals Study Guide

Networking fundamentals teaches the building blocks of modern network design. Learn different types of networks, concepts, architecture and... Read More »