Antenna beamwidth? - RF Cafe Forums

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

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? :?
 
   
 
nubbage
 Post subject:
Posted: Mon Feb 12, 2007 5:00 am 
 
General
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