A PowerPoint presentation on Optical Amplifiers.pptx
- 2. Introduction to optical amplifiers In long haul data transmission, transmission impairments (like attenuation or noise) takes place as signal travels through an optical fiber which results in reduction of signal strength. In order to reduce these transmission impairments, an optical amplifier is used which helps to amplify the weak signal. But unlike a repeater (which converts an optical signal into an electrical signal, and the electrical signal is then amplified and converted back to an optical signal), optical amplifiers directly amplifies the signal without any conversion from optical - electrical and electrical – optical.
- 3. Types of optical amplifiers Optical amplifiers can be of the following types; Semiconductor optical amplifier (SOA) Fiber Raman and Brillouin amplifier Erbium doped fiber amplifier (EDFA)
- 4. But among the listed amplifiers, EDFAs is mostly used to compensate for loss in an optical fiber (most commonly telecommunication optical fibers) in a long-haul or long distance optical communication. EDFA was invented in 1987 in which before that repeaters are used. EDFA is used in the C band and L band where loss in telecommunication optical fiber becomes less in the entire optical telecom wavelength band.
- 5. Characteristics of EDFAs EDFAs is mostly used due to some of its characteristics; It can be used to amplify multiple optical signal simultaneously and because of this can be used with wavelength division multiplexing (WDM) technology. It can be used as a booster, inline and pre-amplifier in an optical transmission line. - when used as a booster – it is placed right after the transmitting end in order to increase the optical power or signal strength of the input signal before it is launched into the transmission line.
- 6. ⁻ when used as an inline amplifier – it is used for compensating the loss along the transmission line (due to attenuation induced by the fiber). ⁻ when used as a pre-amplifier – it is placed at the end of the transmission line before the receiver in order to amplify the weak signal which enables the receiver to detect the transmitted signal. Typical distance between each EDF amplifier is several tens of kilometers.
- 7. Working principle of EDFA