#Optisystem lesson windows

The RUNGE-KUTTA method with fourth order accuracy is the numerical method used to calculate the input pump power and gain for EDFA. WDM systems are divided into three different wavelength patterns РІР‚вЂњnormal (WDM), coarse (CWDM) and dense (DWDM). A WDM system uses a multiplexer at the transmitter and a demultiplexer at the receiver to split them apart. This technique enables bidirectional communications over one strand of fiber, as well as multiplication of capacity.

In optic fiber communications, WDM is a technology which multiplexes a number of optical carrier signals onto a single optical fiber by using different wavelengths (colors) of laser light. WDM is a technique of sending signals of several different wavelengths of light into the Fiber simultaneously 5. The EDFA consists of three basic components: length of erbium doped fiber, pump laser and wavelength selective coupler to combine the signal and pump wavelengths The optimum fiber length used depends upon the pump power, input signal power, amount of erbium doping and pumping.Р”В®DFA can be employed in wavelength-division multiplexing (WDM) system, especially DWDM system. The wavelength range 1525 nm to 1565 nm is known as the C-band or the conventional band and the second band from 1568 nm to 1610 nm is known as the L-band or the long band. EDFA can be used to amplify signal in two bands of wavelengths in the third transmission window. So, more and more researchers are exploiting use of EDFAs in WDM systems in order to improve their performance. For long distance communication, EDFAs with high pumping power and larger link length are available these days. The advent of EDFA has enabled the optical signals in an optical fiber to be amplified directly in high bit rate systems even beyond Terabits. This is more than enough to amplify data channels with the highest data rates without introducing any effects of gain reduction. It could be pumped effectively at wavelengths of 980nm or 1480nm and displays gain in the 1550 nm region.Р”В®rbium Doped Fibre Amplifier: A particular attraction of EDFAs is its large gain bandwidth, which is typically tens of nanometers. Here the doping of silica core is done with Er3+. Their operation is the same as that of a lasing device. Optical amplifiers are devices which can amplify the optical signal directly without electrical to optical and optical to electrical conversion. For efficient utilization of bandwidth, dense wavelength division multiplexing is a technique which allows parallel transmission of various optical channels at different frequencies on a single fiber. But currently, various optical fibers are available with low losses (0.2 dBРІв‚¬вЂўkm) which can be efficiently utilized in various multiterabit and bandwidth efficient applications. In the early days, optical fiber could not be used for commercial applications because it had a very high attenuation of up to 1000 dBРІв‚¬вЂўkm. The optical fiber is the only medium that offers such a huge bandwidth by means of a better performance.

The most recent information indicates that multimedia and high-capacity wavelength division multiplexed (WDM) networks need high bandwidths.

#Optisystem lesson windows

For communication, there are two windows 1530-1560nm(C-band) and 1560-1610nm (L-band). EDFA is an amplifier that is best used because of its low loss and high gain.

The design parameters such as: erbium ions concentration, EDF length, isolators, wavelength division multiplexing (WDM) position, pump power position,circulators, pump directions, all of these elements and factors are affecting directly the amplifier output. Gain, noise figure, wavelength, power flatness and power output are directly affected by any element or parameter inside the amplifier configuration. Fiber amplifiers are crucial and fastgrowing field in the communication system The studyof the this field show that the formulation procedures of lasers generation and amplifier amplification displays aproblematical process due to the factors affecting and changing amplifier and laser significances in a dynamic way.