OSSB Modulation

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Hi all,
How do I do SSB modulation in optical domain? If I use filter to suppress one of the two side-bands, what is the filter that I should be using?

[umer syed]

hi gokul boro,
Real SSB iS difficult to implement in the optical domain. In addition, simulations of the transmission of pseudo-random bit patterns with large extinction ratio for the modulation, which is the way AM modulation is usually done in optical systems, show that pure SSB modulation may not be the best solution.

However, the three VSB modulation embodiments of the appara-tus according to the invention to be described below, give a significant improvment of the achievable transmission distan-ce.
i have attached a pdf file …hope it may help

[umer syed]

u can also refer to the below link…
https://www.google.co.in/patents/CA2221445A1?cl=en

[aasif bashir dar]

hi umer syaed,

i could find the of optical suppressed side band modulation and VSBin the link you mentioned above link,

but it does not provide any help regarding the genneration of the such modulation systems in the optisystem

with regards

[–]

Hi Umer Syed thank you for replying.
I can see many optical filters available in the component library of Optisystem. I want to use one of those filters for suppressing one of the two sidebands. In some paper I often see using tunable optical BPF. Can you please tell me what among the available components gives better results.
Also I do see FBG filters. If anybody has used it as filter then please let me know how can it be used as a filter.
Thanks.

[Aabid Baba]

Hello Gokul boro,
Well as far as i am concerned , talking about filters you may use tunable filters to fulfill your requirement of suppressing one of the two bands. You may use fabry parot filter for your system design. In recent topics alistu had provided a link which had mentioned and given a detail about filters to be used in different applications scenarios. I would like you to have a look at that topic.

regards

[aasif bashir dar]

hi gokul,
i have my self used this filter.
FBG is the component that has three three in optisystem(but practically two ports),
taking of FBG in optisystem,
it has one as input, in which optical signal acts as input
then two remaining provides the reflection and transmission spectrum,

the frequency you have to suppress in the transmission spectrum is the frequency you have to replect back,

i suggest you to use uniform gratting in the filter library.
the frequency you want to reflect back or suppress in transmission spectrum can be edited.

i hope it will help you in using grating

hope you reply soon

with regards

[–]

Thank you aasif. Now it seems better.
Since there are two output ports, what do I do with these ports? If Transmission port is used as inputs to fibers, what will I do with the reflection output. Can it be left unused without affecting the output.

[aasif bashir dar]

hi gokul boro,

you are welcome
what the spectrum you need to process you connect that , and leave the other output unused.(i suggest to see sample of FBG or ant tutorial for FBG on optiwave website), if you donot get any thing , i will surely help you, because i am my self doing work of gratings
it will have no interference with the other system

with regards

[love kumar]

u can use phase shift method at transmitter and modulate it with the help of dual MZ modulator

[aasif bashir dar]

hi love kumar,
please explain “use phase shift method at transmitter and modulate it with the help of dual MZ modulator”

how can it lead to ssb or VSB modulated signal..

i hope you will reply soon.

with regards

[aasif bashir dar]

hi gokul boro,
i suggest to go to optisystem sample, there i have seen the vestigial side band suppression carrier signal gennerated in the folder of advanced modulation schemes. hope they may also provide some idea as well

with regards

[Ranjeet Kumar]

Hi Gokul,
Many designs are available for OSSB modulation with tunable optical carrier-to-sideband ratio with FBG-based acousto-optic tunable filter,we also Power optimized OSSB modulation to support multi-band OFDM services along hybrid long-reach WDM-PONs and Subcarrier Multiplexed transmission system employing OSSB modulation.
These are the links which may be helpful for you to design.
http://www.sciencedirect.com/science/article/pii/S0030399215001164
http://www.sciencedirect.com/science/article/pii/S1068520015000450
http://ieeexplore.ieee.org/Xplore/defdeny.jsp?url=http%3A%2F%2Fieeexplore.ieee.org%2Fstamp%2Fstamp.jsp%3Ftp%3D%26arnumber%3D4632899%26userType%3Dinst&denyReason=-133&arnumber=4632899&productsMatched=null&userType=inst

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Thank you all’
Hi aasif there are many files in that folder. And I cant see any design named vestigial side band suppression carrier signal generated in the folder of advanced modulation schemes. Will you please specify what is the name of that design in the example.

[aasif bashir dar]

hi gokul boro,

there are certainly, for the convienvce i will attach the path of the file.
C:\Users\Aasif dar\Documents\OptiSystem 14.0 Samples\Advanced modulation systems.

in advanced modulation scheme ,, open NRZ

scroll the .osd file upto down , you will find the VSB-NRZ,

with regards

[aasif bashir dar]

hi gurukul,

for convience every body in the current discussion i sam attaching the same sample file from the very folder i mentioned.

regards

[love kumar]

hi aasif.. uploading a pdf fr your ready reference .. i useed this technique years ago n its working … VSB is alos kwon as TSB( Tandom side band) in optical domain .. for that you have to give phase shift of 45 and for single side band phase will be taken as 90…

[love kumar]

pdf file for ssb

[aasif bashir dar]

hi love kumar,
i apprecioate your efforts,
the pdf you have uploaded contains every thing which gokul needs, beside i also have attached the .osd sample file of VSB before.

thanks for uploading such valuable pdf . cheers
with regards

[SAHIL SINGH]

yeah really graet effort by the love kumar,
i appreciate his efforts

regards

[Author]

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