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Wireless Signal Fluctuation. Weird Results.

  1. Sep 14, 2011 #1
    Hi there,

    I'm taking some measurements of a wireless signal using InSSIDer 2.0. Sometimes the signal fluctuation is upwards of 20 dBs, and sometimes the fluctuation is almost nothing.

    It is a very short range signal. There is minimal fluctuation in the signal shown when I'm 10 metres away from the source. But when I move to 50 metres, the signal fluctuation is huge.

    I know almost nothing about this type of thing. All I know is that my data is fishy. very fishy.

    So my problem boils down to this: There could be an issue with the transmitter, the receiver, the software, or no issue at all. I'm not looking for a cut and dry answer, I just would like a direction to start my troubleshooting in.

    Thank you kindly:)

  2. jcsd
  3. Sep 14, 2011 #2


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    Staff: Mentor

    Sounds like a multipath interference issue. Is this a 2.4GHz application?

    Multipath interference is when the reflections off of other objects come to the point where your receiver is, and cause constructive/destructive interference. And since the human body interacts with 2.4GHz signals, you can get varying multipath interference as people walk around the area. And definitely if you have moving vehicles involved, there is a lot of multipath fluctation in RX signal strength.


  4. Sep 14, 2011 #3
    Yes it is 2.4 GHz. The area in which I'm testing is fairly void of movement. There are almost no cars or people. I'm also testing with a line of sight between the transmitter and receiver.

    This is why its so strange to me. I tried to minimize variables but my data doesn't reflect that at all :confused:
  5. Sep 14, 2011 #4


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    Staff: Mentor

    Are there other sources of 2.4GHz in the area? Any microwave ovens? Any WiFi? Do you have your cell phone on?
  6. Sep 14, 2011 #5
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