Search Results for 'wdm'

[FAYIQA NAQSHBANDISpectator]

Hi Ranjeet

No thats not what i mean.Infact AWGs are being mostly used to implement the DWDM systems.This popularity is largely due to the fact
that AWG-based devices have been proven capable of precisely demultiplexing a high number of optical signals (carrying information at various wavelengths) with relative low loss.
So try designing your system using AWG.Infact the integration of the AWG offers many advantages such as compactness and reliability which are also the important requirements of any system design.

Regards

[Ranjeet KumarParticipant]

Thank you FAYIQA NAQSHBANDI ma’m
It means WDM mux improve the results better than Arrayed waveguide gratings.

[Ranjeet KumarParticipant]

Hi Fadil,
Here i am uploading osd file 32 channel wdm system with advanced modulation format of CSRZ using symmetric compensation technique and bit rate of 40 gbps for transmission distance varies from 60 km to 1500 km by just increasing the no of loops, upto 1200 km or more you will get good q-factor and Min. BER. use this as reference you can design for MDRZ AND DRZ modulation formats too.
it is very good design and complex one.

[ZULKARNAINParticipant]

hi amit garg….
As already discussed by Damian Marek in one of the post the buffer selector is a simulation tool to grab certain signals (from the different signal iterations) generated in bidirectional or loop simulations.
As suggested by him you can go through the bidirectional tutorial:

Lesson 5: Bidirectional Simulation — Working with Multiple Iterations

Also i am attaching a link of the post in which this topic was discussed.Hope you will get benefit from this.

Problem in simulation of Buffer selector in TWDM PON

With regards

[ZULKARNAINParticipant]

As for as your error is concerned it may be because of buffer selector when it calculates again n again then reason would be any free port.check all the ports in system if any port is free then attach null signal there.
For your reference i am attaching few links in which you might find some help regarding this problem,

TWDM PON

BUFFER SELECTOR

with regards

[Ranjeet Kumar]

Hi everyone,
I am facing problem in simulation of Twdm pon because when i simulate the design , during simulation a long time has been used in simulation of Buffer selector although i Have used only two Buffer selector in Transmitter ONU 1 and 2. But when i see during simulatio it shows simulation of Buffer selector. I have waited for nearly 45 minutes but not simulation completes. could anyone suggest how to get rid of that problems. When i remove buffer selector i get simulation completes in 1 minutes but not get BER and Q-factor in Uplink direction.

[FAYIQA NAQSHBANDISpectator]

Hi ahmed

also check the link i am posting below.

https://dru5cjyjifvrg.cloudfront.net/wp-content/uploads/2016/03/WDM-Ring-WISE-NRZ-DM1.osd

See if it can be of any help to you.

Regards

[Naazira BadarParticipant]

Hi Fadil..

Well yeah, that seems to happen especially when more than 4 channels are being used.
I believe changing the bandwidth of the WDM MUX/DEMUX can change the Q.F. of the channels you have an issue with.
Try reducing the bandwidth by a small value and check if anything improves. If an improvement is achieved, then you can decide the final acceptable bandwidth of your MUX/DEMUX.

Regards.

[FAYIQA NAQSHBANDISpectator]

Hi Fadil

Does the 18 channel WDM system you have designed work well for a short distance and for 10 Gb/s data rate ?

The performance of the system is expected to change if you are increasing your data rate to 20 Gb/s and simulating it for long transmission reach.You will have to change different system parameters at the transmitter,reciever and in the fiber connecting the two.
Try increasing the launch power of all the 18 sources.
Check if you have properly defined the channels for your WDM MUX and DEMUX.
Use a spectrum analyser to check the power level of all the signals at different points in your design.

These are a few points you can use to trouble shoot your system

see if it helps

Regards

[Fadil PaloiParticipant]

It is a simple WDM with 18 channels compensated with DCF and amplified with EDFA, depends on the bitrate starting from 50km up to 100km space between amplifiers, I have change all what you suggest but no results, for example for the length of 100km, Bitrate of 40Gbi/s, I can achieve Q factor of Q=16.5 for first output, Q=23 for the fifth output Q=19, for the ninth output Q=10.5 and the last one Q=6.8. Bandwidth of the Mux/Demux I have tried from 3*Bitrate, 2*Bitrate 1.5*Bitrate and same as bitrate to when I use it for the single user Q factor goes up to Q=80 but when it comes to multi users such as 18 channels I do not know what I can say. So please I need answer.

[Aabid BabaParticipant]

Hello fadii,
Can you please upload your osd file or brief us about other parameters apart from bit rate ??
At the moment i would suggest you to use an optical amplifier with output gain. or you can increase the bandwidth of WDM MUX/Demux.
You can also try increasing the symbol rate. and for that matter you can also increase power of the system. It would be convenient if you upload your osd file.
Regards

[Fadil Paloi]

Hi I am doing simple WDM for 18 channels and when I change bitrate from 10 to 20Gbit/s after a certain length some of the cannels usually the last ones showing very low Q factor, so difference is very High two to three times lower can anyone tell me what I have to do to get similar Q factor for all the output channels.

[FAYIQA NAQSHBANDISpectator]

Hi aabid….
I just tried using WDM analyzer but i could use it for only two sources.
Anyways, thanks and regards

[FAYIQA NAQSHBANDISpectator]

hi.
Arrayed waveguide gratings are mainly applied in optical fiber communication systems, in particular in those based on multi-channel transmission with wavelength division multiplexing (WDM)……..where individual wavelength channels must be combined or separated e-g TWDM PONs etc…
However i would like to mention that while using AWG for my implementation , my performance was not that gud but using WDM mux/demux separately my performance was better.
Thanks and regards

[FAYIQA NAQSHBANDISpectator]

Hi all,
I am designing or implementing a TWDM PON system. Now what i want to mention hare is that when i previously had increased the bandwidth of MUX (ideal) and the filters i was using ( fabry parot and low pass bessel) , the performance was better than what i ‘d noticed before. I had kept the value around 100 GHz instead of 10 GHz vch usually is the case in optisystem.
Increasing b.w does affect the performance.
thanks and regards