I've seen the ring described as a ground plane, and as a series of 1/4 wave vertical filters. The polarization is probably just the antenna element itself. I don't think that a filter would care. It looks like Don's comment about putting the patch just below the rim is pretty close. I've been playing with it, and a CD about 3/16" below the rim plane with the patch sitting on top gives a pretty good pattern. I need to find something else to use as spacers so I can get about 1/8" lower to see how it plays.
Bob >________________________________ > From: Bob Camp <li...@rtty.us> >To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency >measurement <time-nuts@febo.com> >Sent: Thursday, October 10, 2013 8:04 PM >Subject: Re: [time-nuts] Choke Ring Antenna - Patch Placement? > > >Hi > >The first design principle they seem to use is to attenuate low angle signals. >The assumption is that they are bouncing off ground level targets and then >into the antenna. If there is a second principle (like polarization selection) >it's not really clear how they are getting that job done. > >Bob > > _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
