EDFA Seminar By EE566 Geno G James Optical

EDFA Seminar By: EE-566 Geno G James Optical Communication

What is EDFA • • • Type of Optical amplifier Stands for “Erbium Doped Fiber Amplifier” Used to boost the intensity of optical signals being carried through a fiber optic communications system Has a fiber whose core is heavily doped with Erbium ions Works on the concept of stimulated emission Operates in the C band (1530 -1560) and L band (1570 -1610)

Origin of EDFA (Who, When and Where) • • • Prof. David Payne and team Published the research paper in the year 1987 At the University of Southampton, UK

Why Erbium? • • • Erbium has several important properties that make it an excellent choice for an optical amplifier Erbium ions (Er 3+) have quantum levels that allows them to be stimulated to emit in the 1540 nm band, which is the band that has the least power loss in most silica-based fiber. Erbium's quantum levels also allow it to be excited by a signal at either 980 nm or 1480 nm, both of which silica-based fiber can carry without great losses

How it works • Energy band of Erbium Demo

Basic block diagram of EDFA

Block diagram of EDFA • Copropogating Pump EDFA

Block diagram of EDFA • Counterpropogating Pump EDFA

Characteristics of EDFA • Gain and Noise

Characteristics of EDFA (Contd…. )

Advantages • • Commercially available in C-band & L-band Insensitivity to light polarization state High gain Low noise figure: 4. 5 d. B to 6 d. B No distortion at high bit rates Simultaneous amplification of wavelength division multiplexed signals Immunity to cross talk among wavelength multiplexed channels

Advantages (Cont…) • • Do not require high speed electronics Independent of bit rate (Bit rate transparency)

Drawbacks • • Pump laser necessary Need to use a gain equalizer for multistage amplification Difficult to integrate with other components Dropping channels can give rise to errors in surviving channels

Companies • You name them………. and they are there

References • • • DWDM Fundamentals, Components and Applications by Jean. Pierre Laude Fiber Optic Communication Technology by Djafar K. Mynbaev and Lowell L. Scheiner www. soton. ac. uk www. photon-x. net/tech/edfa. htm www. webopedia. com www. mse. vt. edu

Thank You