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Visible Light Communication Measurement

Discussion in 'Radio and Communications' started by Asphandyar Ali, Feb 19, 2017.

  1. Asphandyar Ali

    Asphandyar Ali New Member

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    Hello, my thesis is based on providing mobility to a Lifi user in a room using LED transmitters. I will be adjusting the distance between LEDs to give a continuous pattern in a specific room so there's no void space left between the signal lobes. For that I need to physically move the detector under a transmitting LED to check 'Signal Strength'. The photodetector (receiver) is connected with Channel 1 of the oscilloscope, what do I measure to determine signal strength including point of disconnection, using oscilloscope?

    Hint: I have measure dc levels and form a tabular data!
     
  2. Tony Stewart

    Tony Stewart Well-Known Member Most Helpful Member

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    What specs do you hope to meet?
     
  3. Asphandyar Ali

    Asphandyar Ali New Member

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    Its a simple test to determine signal strength received from the LED. I want to know what parameters should I note down during the test that show the strength of signal at different angles of the LED.
     
  4. dave

    Dave New Member

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  5. Asphandyar Ali

    Asphandyar Ali New Member

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    The important question is how do I determine the signal strength on an oscilloscope? I am getting a thick ugly sinusoidal wave there and I know I gotta check the DC levels but I am not sure about the intervals. I expected to take one reading for one location of the detector.
     
  6. Tony Stewart

    Tony Stewart Well-Known Member Most Helpful Member

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    It is not so simple to get the LiFi data rates of 10Mbps with a PD+TIA amplifier. not DC. But this is what is needed.
     
    Last edited: Feb 20, 2017
  7. Asphandyar Ali

    Asphandyar Ali New Member

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    Yes its not. My thesis is on providing mobility to the user in a specific room, not much worried about 10 Mbps, but I have a question! How do you determine its 10 Mbps? I provide 4 Mhz to the LED driver and it reflects on the oscilloscope!
     
  8. Tony Stewart

    Tony Stewart Well-Known Member Most Helpful Member

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    10Mbps is just what I read is commonly used.
     

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