[rahul kumarParticipant]

Hi mohammed ridha al-shamapti,
I am surprised to know such problems you are facing.
I don’t think Optisystem software has such problems with windows.
Reboots can also be necessary when updating or removing certain types of software.
Software programs sometimes want to reboot your computer when you install, uninstall, or update them.

Thanks and regards
Rahul

[rahul kumarParticipant]

Hi Dhiman Kakati,
We can’t design space division multiplexing in optisystem.
It is latest field of research in the fields of wireless comminication find applications in Massive MIMO.
Optical communication technology has been advancing rapidly for several decades, supporting our increasingly information-driven society and economy. Much of this progress has been in finding innovative ways to increase the data-carrying capacity of a single optical fibre. To achieve this, researchers have explored and attempted to optimize multiplexing in time, wavelength, polarization and phase. Commercial systems now utilize all four dimensions to send more information through a single fibre than ever before. The spatial dimension has, however, remained untapped in single fibres, despite it being possible to manufacture fibres supporting hundreds of spatial modes or containing multiple cores, which could be exploited as parallel channels for independent signals.The use of multiple parallel optical paths in the form of space division multiplexing/spatial division multiplexing (SDM) is seen as the way forward. SDM is implemented through the use of Multiple Fiber arrays, Multicore Fibers (MCF), Multimode Fibers (MMF) and Few Mode Fibers (FMF) to increase the available bandwidth.

[rahul kumarParticipant]

Hi syed fareed,
We could use FSO in underwater communication.
Many research have been done ..
http://ebooks.cambridge.org/chapter.jsf?bid=CBO9780511979187&cid=CBO9780511979187A065
http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=6214706
https://www.researchgate.net/publication/233854960_Smart_Transmitters_and_Receivers_for_Underwater_Free-Space_Optical_Communication
http://gradworks.umi.com/35/75/3575838.html

[rahul kumarParticipant]

Hi,
As we use wireless optical channel component, that is also free-space optics, can be used for large distances where the atmospheric attenuation is not the major source of penalties, but the pointing angle is. e.g. satellite communications. The impaired link performance from pointing errors between the transmitter and receiver for satellite communications.
https://www.osapublishing.org/jocn/abstract.cfm?uri=jon-2-6-178
http://www.ciitresearch.org/dl/index.php/pdcs/article/view/PDCS092009004
http://www.ijcaonline.org/archives/volume104/number10/18235-9224
http://proceedings.spiedigitallibrary.org/proceeding.aspx?articleid=1268928
The above links will help you.

[rahul kumarParticipant]

Hi Saruchi Attri,
First design the system as per your requirements and then replace single mode fiber with Free space optics(fso).
You should refer to the optisystem samples file and try to learn from there.

Free Space Optics (FSO)

http://staging.optiwave.com/forums/topic/free-space-optical-links-optical-system/
http://staging.optiwave.com/forums/topic/log-normal-channel-in-fso/
Please refer to following links.

[rahul kumarParticipant]

Hi,
If the dispersion coefficient parameter of the fiber is negative, the frequency increases across the pulse from the leading to the trailing edge that is referred to as the positive frequency chirp. On the other hand, the frequency chirp is negative, i.e., the frequency decreases across the pulse from the leading to the trailing edge if the dispersion coefficient parameter is positive. Therefore, the rate of pulse broadening in the fiber with negative dispersion coefficient parameter compared to that expected from the GVD alone. However, the broadening rate decreases during propagation in the fiber with positive dispersion coefficient parameter, as the two chirp contributions cancel each other.

[rahul kumarParticipant]

Hi Khadija Omran,
The relation between the length of SMF and DCF and also between Dispersion coefficient of both is given as:
D1*L1 + D2*L2 =0, where D1 and D2 are Dispersion coefficient of SMF and DCF RESPECTIVELY, while L1 and L2 are length of SMF and DCF respectively. This means D2 will be always negative.

Thanks and regards,
Ranjeet

[rahul kumarParticipant]

Hi Khadija Omran,
I think there is no limitation of length of DCF. It is proportional to length of SMF.
That is when length of SMF increases we have to increase the length of DCF.
Seeking your response.