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hi rajguru. thanks for your reply.. i want to trace a graphs for BER vs Crosstalk .. is it possible in optisystem are some other technique is required for doing is task ..
Lasers can be divided into three main categories: continuous wave (CW), pulsed and ultrafast.
As their name suggests, continuous-wave lasers produce a continuous, uninterrupted beam of light, ideally with a very stable output power. The exact wavelength(s) or line(s) at which this occurs is determined by the characteristics of the laser medium. For example, CO2 molecules readily lase at 10.6 µm, while neodymium-based crystals (like YAG or vanadate) produce wavelengths in the range between 1047 and 1064 nm. Each laser wavelength is associated with a linewidth, which depends on several factors: the gain bandwidth of the lasing medium and the design of the optical resonator, which may include elements to purposely narrow the linewidth, like filters or etalons.
If a laser can simultaneously produce different lines, the first step in determining the operating wavelength is to use cavity mirrors that are highly reflective only at the desired wavelength. The low reflectivity of the mirrors at all the other lines will prevent these from reaching the threshold for laser action. However, even a single laser line actually covers a range of wavelengths. For example, laser diodes produce light over a wavelength range of several nanometers corresponding to their “gain bandwidth.”
The specific wavelengths of the output beam within this gain bandwidth are determined by the longitudinal modes of the cavity. Figure 4 shows the behavior of a two-mirror cavity, the most basic design. To sustain gain as light travels back and forth between the mirrors, the waves must remain in phase and “reproduce” their wave pattern, which means that the cavity round-trip distance must be an exact multiple of the wavelength
Nλ = 2 × Cavity Length,
where λ is the laser wavelength and N is an integer called the mode number. This is usually a very large integer, since the wavelength of light is so much smaller than a typical cavity length. In a high-power laser diode, for example, the IR output wavelength is 0.808 μm, yet the cavity length may be 1 mm, so that even in a very small laser resonator, N is ~2500. Wavelengths that satisfy this resonance equation are called longitudinal cavity modes [from edu.photonics]
hi all thanks for your concerns and devoting tour time to solve me issue .. i agree with all ho you no direct method is there to measure the crosstalk in opti system .. do anyone aware about mathematical relation of signal power and crosstalk for DWDM system … it will be very helpful for me
another file
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hi Rajguru … sending you a paper on TWDM 4 channel system ..i guess it will be beneficial to you..please find the attachment ….. if facing any problem in downloading .. send me a test mail on er.lovekumar@gmail.com
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hi Tanveer ,
yes definetly you can design such framework in opti system .. i agree with rajneet and abid baba .. some examples are given by optiwave too for ring network .. use need to use ADM in Ring Network and other component as suggested by aabid baba
hi .. please follow the link http://staging.optiwave.com/forums/topic/matlab-2/#post-38344
here are PDF file that might be helpful for you to understand the Matlab compatibility with optsys
hi kanwarjeet singh .. optisys in forward compatible .. and you optisys 7 file will definitely work in optisys 14… you can create a partition in your system too as explained by rajguru as well as atul.. both approaches are good
totally agree with rajguru mohan .. Nice explanation Rajguru, M Mohan ..
hi ranjeet.. i guess it may be due to nonlinerilty in DWDM system .. you can try nonlinerilty control for better results..
hi… i think length of DCF is depend upon the dispersion amount due to SMF .. basically it is calculated with relation L1D1+ L2D2= 0
where L1= length of SMF
D1= dispersion slope in SMF
L2= length of DCF
D2 = dispersion slope in DCF
and i am agree with dihman that avoid to use long DCF .. instead loop concept give better results
another one
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find enclosed files
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hi dhiman .. uplaoding file again … if you dnt get it this time give me your email id i will forward to your inbox