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Antenna beamwidth? - RF Cafe Forums

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 Post subject: Antenna beamwidth?
Posted: Sat Feb 10, 2007 3:30 pm 

Joined: Sat Apr 23, 2005 2:09 pm
Posts: 17
Location: Tampa, FL

If I am given an antenna pattern plot that looks like this:

How would I estimate its beamwidth?

I was thinking that I find the point where the antenna shows the maximum gain and trace through the plot from one side finding the 3-db point and trace the opposite side finding another 3-db point. Is this correct? :?

 Post subject:
Posted: Mon Feb 12, 2007 5:00 am 
User avatar

Joined: Fri Feb 17, 2006 12:07 pm
Posts: 218
Location: London UK
Yes, that is correct.
Some people quote the full side-to-side beamwidth as you describe, while others state the angle as +- x degrees, ie each side of the max gain direction.

Posted  11/12/2012