Dual horizontal and vertically polarized antennas, fed with signals 90 degrees out of phase. ----- Original Message ----- From: Dale Kelly To: opendtv@xxxxxxxxxxxxx Sent: Friday, April 29, 2011 1:43 PM Subject: [opendtv] Re: Circular, elliptical antenna polarization improves mobile DTV reception reliability In my limited experience the “true” C.P. antenna is of Helical design, are there others configurations?