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Spectrum analyser analysis

Discussion in 'Inspire 1 Discussion' started by Mark C, Jul 20, 2015.

  1. Mark C

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    I have just got a spectrum analyser which is needed to obtain my RPAS permissions.
    Iam trying to work out how to analyse the results.
    Mine covers the 2.4gHz range for here in the UK.
    I turn on the analyser and then are shown the peaks of activity across the 2.4gHz range in the immediate area. So in a built up area lots of action.
    How do I check that the RPAS is not going to encounter spectrum fratricide?
    Do I then turn on the inspire and see where my "peak" is in relation to other traffic and if so how do I then interpret the results?
    Under what circumstances after doing a sweep would you consider it to risky to fly?

    Thanks
     
  2. The Editor

    The Editor Moderator
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    Hi Mark,

    I'm not sure why you think you require a spectrum analyser to gain PFAW, or are you talking about CAOSC which has now been replaced by OSC submissions only.
    Are you talking about normal exemptions under standard PFAW or something less restrictive?
     
  3. Scotflieger

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    Which Spectrum Analyser have you brought? I have the RF explorer 24 that I have programmed to cover the full Inspire 1 employed band as follows:

    Centre Freq 2441.500 MHz
    Freq Span 85.000 MHz
    Start Freq 2399.000 MHz
    End Freq 2484.000 MHz

    You will see the display showing all 2.4GHz sources across the band. These will be wifi, smart phones, key fobs, etc. What you need to ensure is that you control signal is greater than the rest - referred to as signal to noise ratio. With your I1 and RC off, you want see nothing greater than -50 to -60 dBm. Leave the Spectrum Analyser monitoring for about 5 mins. If you see many peaks above the level mentioned, go somewhere with less interference. When you power up the I1 and RC you will see a spike at about -30dBm. This is your C2 and LightBridge video link signal. It will move around to find a clear spot.

    @Editor Resource Group strongly suggest you need a Spectrum Analyser for their Flight Assessment and written into your UAS OSC.
     
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  4. The Editor

    The Editor Moderator
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    Wow......they don't have shares in RF Explorer corporation do they? :p
    It was 'mentioned' when I did my course but pointed out it was not a requirement.
    I think my pager size pocket lightning detector got more attention. :D
    Everyone is gonna want one of those now.....detects lightning up to 50 miles away and informs you if the storm is moving toward or moving away from you!
    With so many gagets we are not going to have room in our case for the Inspire!!!!
     
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  5. Mark C

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    Scot,
    Thank you very much for your explanation I now understand.
    It seems a good idea to me to use it as part of pre flight checks.

    Ed, Do I note a slight level of sarcasm?....lol...where do I get a lightning detector from I like the sound of it!
     
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  6. The Editor

    The Editor Moderator
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    Me....sarcastic???? How very dare you sir :p

    Ere ya go..... -> http://www.strikealert.com/lightning_detector_products_strikeAlert.html
     
  7. The Editor

    The Editor Moderator
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    Me....sarcastic???? How very dare you sir :p

    Ere ya go..... -> http://www.strikealert.com/lightning_detector_products_strikeAlert.html