antenna feed cable pattern perturbation - RF Cafe Forums

RF Cafe Forums closed its virtual doors in late 2012 mainly due to other social media platforms dominating public commenting venues. RF Cafe Forums began sometime around August of 2003 and was quite well-attended for many years. By 2012, Facebook and Twitter were overwhelmingly dominating online personal interaction, and RF Cafe Forums activity dropped off precipitously. Regardless, there are still lots of great posts in the archive that ware worth looking at. Below are the old forum threads, including responses to the original posts. Here is the full original RF Cafe Forums on Archive.org

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

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

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