How to form Simulation model of WDM PON using downstream DQPSK & OOK upstream

Hi Umar,

Welcome to Optiwave forums! Could you please attach the paper you are trying to reproduce, as there is remodulation and more information might be needed? Since you seem to be new to Optisystem, I strongly suggest that you go through Optisystem samples on multi-access systems to get insight about how to implement PONs. This might be quite helpful to you.

Regards

Hello Umar,

As it was mentioned before by Alistu, the reference on paper with the scheme that you are trying to implement is highly recommendable. At the same time, could you, please, attach the scheme itself? As I understood from your description, you are planning to use different modulation formats for down- and upstream. However, what did you mean by “one half of the signal is send to the DQPSK receiver”?

Hi!Umar farooq
Welcome to optiwave,Attached paper can be implemented in optisystem.You can also takre help from optiwave samples of wdm pon,which ,in turn gives you the basic idea of how does wdm pon works .you can make changes in sample file such as change OOk to Dqpsk and receiver at user end.in this way you will get two sihnals at 45 and -45 .Yoi can use one of then as user signal detected and other one circulate and reuse it for upstream.Hope it would help you ,i will also provude you some links of similar discussion and topic which discussed here in forum containing setups too.

Kindly visit these kinks for detailed information.Once you get to knoemw the system working.It would be easy to implemnt ehat you trying to do

Eye Diagram obtained from PON using WDM Mux

Dowload setups and try to simukate by own and nake changes into it.If you will find any probkem ,you can share with us .

Welcome,since you are asking about best modulation format then i would suggest you the DQPSK.However now all the modulation formats are like NRZ RZ DPSK MDRZ etc are provide different results and performance in different systems.Moreover you can try them by your own.lot of article you find on net regarding these formats and it is hard to find only one format to use which comes out best because different papers has differebt modulation format best according to scenario.For example if you kept non linearities off then Dpsk performs best and csrz mdrz also provide good results than Rz Nrz due to less prone to dispersion and are bandwidyh efficient .But where you consider non linearities ,trend become opposite ,here Rz performs better due to less prone to non linearities but yes more dispersion and bw requirements.So there is trade off between these .As i have seen many papers on PON and maximum use DQPSk has been analyzed for NG PONS .