# Understand Radio Pattern of a WIFI antenna

I have a Fortigate AP, and need to understand its radio pattern for optimal positioning.

I've already understood the E-plane and H-plane representations and also that number on the circumference of the circles are radiuses.

But what are the values listed vertically down to the center of the circle and what do they mean, how can I equate that to any distance(in meters).

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• The E-plane patterns look completely wrong to me. They should show two bubbles, no radiation above and below the transmitter. – tomnexus Jul 22 '19 at 21:39
• Agreed - this AP seems to have an almost perfect isotropic antenna, something which we all know is basically impossible – Scott Earle Jul 23 '19 at 6:41

• Thanks a lot for the link on link budget ^^, however i didn't really understand this statement if in one particular direction you read 0 on that scale, and in another direction you read -3, then the power in the latter direction is half what it is in the first direction I I also wish to know why are the values negative when closer to the antenna. – Xsmael Jul 22 '19 at 18:47