Understanding Incident Angle

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SIGINT
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Joined: Wed Oct 19, 2016 10:19 pm

Understanding Incident Angle

Post by SIGINT » Mon Sep 14, 2020 6:16 pm

How do I read the Incident Angle display on the KerberosSDR app ?

Is the degrees alligned with North - if the line from antenna 3 to antenna 1 is pointing North ?

Second - the compass - it shows +/- degrees - suggesting it is referring to an angle left/right of a heading - which is non existing on a stationary setup.

Again, if the A3 -> A1 line is permanently North - will the compass show direction with 0 degrees on top = North ?

rtlsdrblog
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Re: Understanding Incident Angle

Post by rtlsdrblog » Thu Sep 17, 2020 5:13 am

The whole incident angle convention is a bit messed up as multiple developers have used different conventions on different displays so it can be a little confusing.

On the DOA graph antenna 1 will always be 0 degrees on the compass display. Let's assume that you point antenna 1 NORTH. Then 90deg is WEST, 180 deg SOUTH, and 270 deg is EAST

SIGINT
Posts: 13
Joined: Wed Oct 19, 2016 10:19 pm

Re: Understanding Incident Angle

Post by SIGINT » Thu Sep 17, 2020 11:23 am

Thanks - that was my suspicion - but likely partly caused by multi path interferrence - my directions has been way off.

I am working from an indoors, permanently mounted antenna - which has just been moved close to the ceiling and a few metal objects in the same height have been removed.

That improved things a bit.

Now, for the compass - which shows +/- degrees on the web browser - I suppose the same applies - would be nice if you could configure the compass to show 360 degrees - and markings every 10 degrees rather than the 15 degree jump for some of the lines. Strains my math brain when late in the evening :-)

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