Bit rate limit

[Dr. Dhiman Kakati]

Hi all,
I am Designed a system using optisystem 13 where I have used Dualpolarization differential quaternary phase shift keying (DP-DQPSK) where i have achieved a bit rate of 20 Gbps maximum,

I have attached the .osd file herewith.

So my question is is there any possibility of increasing further.
or there is a modulation format which I have used here has a limit.

I want to know upto 20 Gbps Q-factor and eye diagram are quite nice.

or is there a need to modify the receiver.

So I need your suggestion in this matter.

Thanks,

With regards

Attachments:

1. for-upload.osd

[Alessandro Festa]

Dear Dhiman, the DP-DQPSK is being currently used tipically at 100Gbps (+ FEC overhead, so real bitrate exceeds 120Gb/s). So the limitations you are seeing are surely arising from the system you are designing. Unfortunately I cannot open your file now since I am at home, but I will try to give it a look next week.

[Dr. Dhiman Kakati]

Thank you so much for the reply.

do you have any sample(.osd file) that you have mentioned “the DP-DQPSK is being currently used tipically at 100Gbps (+ FEC overhead, so real bitrate exceeds 120Gb/s).” please provide me with.

Regards.

[alistu]

Hi Dhiman,

You can find osd files in the OptiSystem samples on DP-QPSK with 100Gbps, although the setups are for back-to-back systems. I have attached one of the samples with some changes I have made to attain 120Gbps without error. It was a back-to-back system, yet I have used a 50-km SMF fiber to be like yours. Please take a look at it.

Regards

Attachments:

1. 112Gbps-Coherent-DP-QPSK_B2B-with-DSP-changed.osd

[Dr. Dhiman Kakati]

Thank you, Alistu for for you kind help,

Regrads

[Dr. Dhiman Kakati]

I have run the .osd file you have provided and it is working fine. Thanks

[Dr. Dhiman Kakati]

Dear Alistu, in your system where you have applied the 120 Gbps PRBS generator, at the optical DP-QPSK transmitter the bit rate you have selected is external PRBS generator, and you have connected the input of the transmitter to the BER test set, where I can find the Bit rate to be 100 Gbps, I am confused.

with Regards

[alistu]

I have not used PRBS generator at all. I have used the BER test set and I have set the bit rate in the layout parameters 100Gbps. I also haven’t applied the 120Gbps bit rate to BER Test Set and have used the script mode to use the same value as the one in the layout parameters. May I ask where you have seen the bit rate to have been put equal to 120Gbps?

[gaganpreet Kaur]

Hi dhiman, to set the bit rate you need to change it in layout properties and in all the connected system you choose the option ‘bit rate ‘ so it will always pick the bit rate applied to simluation.so whatever change you make to bit rate has to done in the layout properties only, all the components will by default use bit rate of simulation. you need not change it for every component. i hope u got things clear.

[Dr. Dhiman Kakati]

thanks gaganpreet for the reply. i have got it. but one more thing i need to mention the transmitter bit rate is disabled here and selected external PRBS, thanks you.

regards

[Dr. Dhiman Kakati]

now its a somewhat clear,
Thanks both of you.

Regards

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