Home Forums SYSTEM Fiber wireless system

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    • #30871
      Prarthana Kashyap
      Participant

      Hi everyone,
      I am stuck in one point of my system design i.e. fiber wireless (Fi-Wi) communication that in the wireless portion, after designing the fiber portion eg. i am using 16-QAM in the optical modulation and demodulation process so after getting the information bits at the remote base station side where there must be some modulation, carrier multiplexing, an antenna for wireless transmission then the fading channel or medium then receiver etc. So I need an exact block diagram for this, and some explanation notes or books. please anyone help. Thanks in advance.

      Regards

    • #30923
      aasif bashir dar
      Participant

      hi prarthana ,

      are you reffereing to free space optics(FSO), where does the anntenas came in optisystem?

      are you using matlab optisystem co-simulation?

      i hope you will soon reply annd explain it for me

      with regards

      • #31048
        Prarthana Kashyap
        Participant

        Hi Aasif,
        Thanks for the reply, I want to do MATALAB optisystem co simulation, and want to design wireless design in MATLAB and integrate in optisystem.

        secondly i do not want to use the Free Space Optics (FSO) in the design as it has two big disadvantages such as its performance is weather dependent i.e. in case of rain or some other parameter this system quality degrades. and one more issue is that there is a need for high accuracy in the alignment i.e. direction is of more concern so for these disadvantages i do not want to use it.

        regards

    • #30928
      prakash jat
      Participant

      hi Prarthana

      could you attach your project file? for check

      • #31049
        Prarthana Kashyap
        Participant

        Hi Prakash,
        Thanks for the response, You can refer to any of the design that is there in the OptiSystem 14 samples in the “Microwave or RF optical system folder”, I basically need the block diagram for the wireless part, then it would be helpful for writting the codes.

        Regards

    • #30929
      Naazira Badar
      Participant

      Hi Aasif..

      Fiber-Wireless(Fi-Wi) or Optical Wireless uses both fiber and mm- waves and is not FSO. It uses fiber at backbone and transmits to clients wirelessly using mm waves.

      • #31050
        Prarthana Kashyap
        Participant

        Hi Nazira,
        Thank you for the reply, and putting one of the most important point more specifically about the mm wave that is used in the electrical domain and multiplied with the bit stream and then the combination is used to the electrodes of the modulator to have it in optical domain.

        Regards

    • #30930
      Naazira Badar
      Participant

      Hi Prarthana..

      Well, I think you need to study about PON networks for this.
      Here is the link to a paper about Fi-Wi where in OptiSystem has been used. Hope this helps.

      Regards

      • #31051
        Prarthana Kashyap
        Participant

        Hi Nazira,
        I am unable to find the link you are referring in the above reply #30930. please reattach again. at present state i am worried about the wireless part. so I was basically asking here for the block diagram that would be very much helpful in case of Radio over Fiber fi-wi system. Thanks for the response.

        Regards

    • #30936
      Aabid Baba
      Participant

      Hi kashyap,
      I believe you are talking about e hybrid optical network here. In these networks , The uniform optical millimeter-wave signal that supports services for wired or wireless users is produced via an LiNbO3 Mach-Zehnder modulator.
      You can refer to the paper for your simulation set up. hope it helps you.

      https://cdn.optiwave.com/wp-content/uploads/2015/09/30094243/OE-141556_Final-proof1.pdf?396c44

      With Regards

      • #31052
        Prarthana Kashyap
        Participant

        Hi aabid Baba,

        Thank you for the response, the paper you have attached is very much helpful in the field of research of radio over fiber, but for the wireless portion mainly the results are shown, and do not have a detailed explanation which I am looking for.

        Regards

        • #31057
          Aabid Baba
          Participant

          Hello Kashyap,
          The network you are talking about is fiber-wireless. What i infer is that it is a hybrid network. Fiber-Wireless(Fi-Wi) or Optical Wireless uses both fiber and mm- waves. While implementing the system design , The fiber part must not be an issue but the other part. Can you tell what specific problem are you facing in implementing so??

          Regards

        • #35449
          Prarthana Kashyap
          Participant

          Hi Aabid baba,
          I am doing now the matlab coding taking into consideration of Rayleigh as well as rician fading channel, I have got may examples regarding wireless rayleigh fading channel that uses BPSK modulation format. I am attaching herewith a MATLAB code. so can you modify the file to integrate to optisystem taking anyone of the example using QAM modulation scheme that is available in the samples folder. please have a look into the .m file. Thank you in advance.

    • #31028
      alistu
      Participant

      Hi Prarthana,

      Please refer to the example provided by OptiSystem as the sample files for the start, and then take a look at the FSO channel implementations attached on OptiSystem topics, namely the one here:

      4QAM OFDM and 16QAM OFDM

      This should help you with the overall architecture. Please let me know if it does.

      Regards

      • #31053
        Prarthana Kashyap
        Participant

        Hi Alistu,
        I do not want to use FSO here as it has some major drawbacks such as its performance is weather dependent i.e. in case of rain or some other parameter this system quality degrades. and one more issue is that there is a need for high accuracy in the alignment i.e. direction is of more concern so for these disadvantages i do not want to use it.

        furthermore the design file in the issue you have referred these results are for only 0.5m which is very less and and we need it in terms of km range in free space optics.
        Thanks for the reply.

        Regards

        • #31120
          prakash jat
          Participant

          hi prathana

          why we are using FSO because of high data rate , secure , fast link design in case of any disaster, cheap compared to all communication , ease of implementation , long distance etc.

          1.long distance can be increased by laser beam (1550nm) with beam control( which is not much tedious work ) ,turbulence mitigation technique like MIMO . OFDM . OAM , non- linear equalization technique etc.(need more…….)
          2. AT 1550 nm , there is no much bad effect of weather condition as well as divergence
          3.noone can intercept it because we can apply encryption at quantunm level
          4.it is so much fast operation (with much wider bandwidth so that you can carry more user at time)
          5.if you want to deploy it anywhere else it doesn’t require licence of spectrum
          6. it can cover thousand of million of KM like ( please visit inter-satellite communication at mars( upcoming))

          let me konw if i am wrong

        • #31326
          Prarthana Kashyap
          Participant

          Hi Prakash,
          I can see FSO advantageous where there is no possibility of laying optical fiber (point no. 6) and in terms of cost otherwise all the factors are you mentioned are available in fiber link. and line of sight is most important in this case so this technique is advantageous in some of the specific case only. Thanks for providing with some useful important points.

          Regards

        • #31153
          alistu
          Participant

          You’re welcome. I should point out that the file I have addressed was just supposed to show the overall architecture. I believe the distance to be a parameter you would have to worry about once you get to have a clear idea about the system architecture. Please refer to the last sentence of #31058.

          Regards

        • #31328
          Prarthana Kashyap
          Participant

          Thanks Alistu for the suggestion. I will definitely look into this matter.. hope to get more help in future design problem which i will be facing.

          Regards

    • #31065
      Dr. Dhiman Kakati
      Participant

      Hi Prarthana,

      I am also working in Radio over Fiber project and attaching here with block diagram snapshot of my case. it might be helpful in your case also upto some extent please have a look. 1st one is the overview of subsystem in radio over fiber link, second is spectrum in optical domain look like and third one is for wireless link. Thanking you.

      Regards,
      Dhiman

    • #31066
      Dr. Dhiman Kakati
      Participant

      Sorry the attachement are missing. Please refer here.

      Regards

      • #31329
        Prarthana Kashyap
        Participant

        Hi Dhiman, Thanks for providing me with the block diagram which I was looking for. I think the wireless portion is going to be a tough job to implement as seen from these block diagrams. anyway thanks a lot. Hope to get more help in future posts.

        Regards

    • #31787
      Ranjeet Kumar
      Participant

      Hi,
      You can learn more on https://optiwave.com/resources/applications-resources/optical-system-free-space-optics-fso/
      tutorials of optisystem and move further for more advanced design.

      • #32487
        Prarthana Kashyap
        Participant

        Hi Ranjeet Kumar,
        I think you are not getting what I am looking for, I need to design fiber wireless system where the wireless portion need to be for normal common uses such a broadband wireless access, again and again i am suggested to go for free space optics but at this point of time I dont want to implement FSO because FSO is not useful in case of uses such as mobile broadnd. Thanks for the response..

        Regards

    • #33407

      HELLO PRARTHANA KASHYAP..
      I have a query plz can you help…i want to ask you after designing your fiber portion what tool did you use for designing the wireless part…did u design it in the optisystem itself…if yes please can you share some osd files which may relate to it and can be helpful…i will be highly grateful to u..
      THanks and regards

      • #35454
        Prarthana Kashyap
        Participant

        Hello Fayiqa Naqsbandi,
        I am trying to design the wireless portion using MATLAB simulation platform and there is no wireless portion components in optisystem, presently I am not getting a fruitful output for the MATLAB code that I need, in most of the technique that i found online from MATHWORKS are for very low data rate. But i want to have as much as possible as everyone needs.. mimo channel i want to use if possible spatial diversity technique.

        Regards

        • #35540
          Dr. Dhiman Kakati
          Participant

          Hi Prarthana,
          I can give you with some more sample code MATLAB codes for the wireless channel, as MATLAB is a different tool than Optisystem so putting them here i think not good.

          Regards,
          Dhiman

    • #33513
      Ranjeet Kumar
      Participant
      • #35455
        Prarthana Kashyap
        Participant

        Hi Ranjeet thank you for providing with the links. i need to look into this matter. From today onward to do my research works.

        Regards

    • #34196
      SAHIL SINGH
      Participant

      Hi Ranjeet Kumar,

      Thanks for the valuable information…. Your efforts are highly appreciated….

      Regards

      Sahil Singh

    • #35457
      Naazira Badar
      Participant

      Hi Prarthana Kashyap..

      This topic is active since quite some time now. Here is another link I am posting. I think the paper is very relevant.
      the link goes as : http://www.sciencedirect.com/science/article/pii/S1068520014000297

      16-QAM is employed in this work as well.

      Regards
      Naazira Badar,

    • #35464
      varinder singh
      Participant

      hi………prathana
      http://phys.org/news/2010-03-fiber-wireless-fi-wi-ultra-high-speed-short-range.html….this one is the first link …….i hope these two link will help yoy in your project………..
      thanks

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