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antenna feed cable pattern perturbation - RF Cafe Forums

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dipole
 Post subject: antenna feed cable pattern perturbation
Posted: Mon Feb 27, 2006 2:33 pm 
 
Lieutenant

Joined: Mon Feb 27, 2006 2:18 pm
Posts: 1
Does anyone know a scheme to minimize scattering from the feed coax of an antenna under test during gain/pattern measurements? Frequency is 2.4 or 5.8 GHz. The problem is for configurations where the coax cannot be oriented perpendicular to the incident field.

Thanks

_________________
Dipole


 
   
 
fred47
 Post subject: Antenna feed scattering
Posted: Thu Mar 23, 2006 8:44 pm 
 
General
User avatar

Joined: Wed Feb 22, 2006 3:51 pm
Posts: 104
HI!

Does it really make sense to make an antenna measurement that has no connection to how the antenna will actually function in the real world??

That said, you might consider the use of RF absorbing material around the cable, to make it appear to have the 377 Ohm impedance of free space.

Good Luck,
Fred


 
   
 
nubbage
 Post subject: Antenna Feed cable Pattern Perturbation
Posted: Fri Mar 24, 2006 11:10 am 
 
General
User avatar

Joined: Fri Feb 17, 2006 12:07 pm
Posts: 218
Location: London UK
This is a fairly old posting, but hopefully not too late.

You could wrap the feeder cable with strips of FM4 ferrite-loaded rubber sheet type FM4 from Feriti.

See www.iskra-feriti.si





Posted  11/12/2012