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    #41878
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    Tayyab Mehmood
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    Thanks Damian for replying with such a helpful material. I have done this part too in the optisystem. I am wondering how one can extract both the signals (high priority and low priority) at the receiver side . Would you please help me in this regard.

    #41831
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    Tayyab Mehmood
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    Still, did not find a solution to do hierarchical modulation in Optisystem 14.0. But succeeded to do hierarchical modulation in MATLAB.

    #41390
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    Tayyab Mehmood
    Participant

    Here is the basic conceptual diagram of hierarchical modulation in the electrical domain

    Attachments:
    #27868
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    Tayyab Mehmood
    Participant

    Hi Dhiman, Send/message me your email ID. I will send you the collection of books.
    Regards

    #27765
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    Tayyab Mehmood
    Participant

    Hi dhiman I have a collection of ROF related books, I am sending the dropbox link for all.

    https://www.dropbox.com/home/Microwave%20photonics%20books

    #27752
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    Tayyab Mehmood
    Participant

    I post my problem in this thread because Hager had the same problem in the beginning of this thread.
    I still did not figure it out whats wrong with the DPSK system.

    Regards

    #27717
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    Tayyab Mehmood
    Participant

    Thanks Alistu and Dhiman for replying.

    Regards

    #27704
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    Tayyab Mehmood
    Participant

    here are the files

    #27703
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    Tayyab Mehmood
    Participant

    Thanks Dhiman and Alistu for replying,
    now I increase the bit rate from 240-Mb/s to 24 Gb/s, increase the length of SMF from 5Km to 100 Km and decreases the input power of the laser from 0d dBm to -5 dBm.
    Still the BER is zero and now the Q-factor is in thousands.
    I think there is a problem with the configured parameters or I am using wrong components for the system.
    Kindly help me in this matter.

    Regards

    #27679
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    Tayyab Mehmood
    Participant

    After reading the whole topic on Radio over fiber system, I concluded that I have the same problem with my system. Although my system is a bit more simple than the above mentioned system was but I am not getting the desired results (BER=10^-12). currently the BER is 0.
    system specifications: bit rate= 240 Mbps ; symbol rate= 120 Msps; bits per symbol= 2 bits;
    frequency of first DPSK modulator is 0.7 GHz; frequency of second DPSK modulator is 1.5 GHz.
    I am attaching the snapshot and the system file below.
    Regards

    #23610
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    Tayyab Mehmood
    Participant

    Thanks Sir.

    #23567
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    Tayyab Mehmood
    Participant

    Thanks sir

    #23559
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    Tayyab Mehmood
    Participant

    Respected Sir , checkout the attached files below , I modify the project file and remove optical circulators from both sides , now I get the desired results.

    kindly see the figure, which shows the spectrum after the amplifier for uplink and downlink.

    #23552
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    Tayyab Mehmood
    Participant

    Thanks Alistu, I am also working on it and trying to modify the examples related to bidirectional fiber to run this simple bidirectional ROF link.

    #23527
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    Tayyab Mehmood
    Participant

    Thanks for replying, but sir problem starts with the uplink, why I am getting the remaining of 193.1 & 193.25 THz at 5 and at 6 ( attached below) and not getting any result at 3 and 4.

    Attachments: