
Originally Posted by
RedRocket
Be aware that polarization plays no role whatsoever in the formation of the narrow main Lobe radiated from this antenna. It is solely determined by the physical arrangement & number of the ant. elements in total. The shape & widths of the Lobe is the result of "Stacking" in the Vert/Horiz planes of the numerous Patchs in each & additionally the phase angles of r.f. current being delivered to each element via the Feedlines.
What role Horiz. polarization would play in this case is quick attenuation of the radar wave over multiple wavelengths distance from the source, & also depending on the dielectric constant of the earth it's propagating over. Az soil is sandy & dry...very lossy .
This Phased-Array consists of 2 antenna Principles for beam formation compression:
A "Colinear Array" consisting of 6-Broadside Arrays stacked one over the other in the Vertical plane.
A "Broadside Array" consisting of 30 Patch elements side-by-side in the Horiz. plane. This arrangement is specifically why the narrow beam formed is only 5 degrees in width. Yes, the beam is compressed in both planes but far more in the Horiz. direction width for obvious reasons of singling out individual vehicles to flash photo & record for citations.
I understand where you are coming from Red, and technically you are correct (you know, I know, you know you are

), the physical design of the antenna is what determines the lobe pattern.....wide vs. narrow.
But we also both know that a Vertically polarized signal radiates in the horizontal plane and concentrates it's energy there while a horizontally polarized signal radiates in the vertical plane getting cut off by the ground on one side and radiating uselessly into the ionosphere on the other.....ie. much of it's energy is wasted in terms of being an efficient ground to ground radar.
Likewise, the Veritical components of a Circularly polarized signal will travel further near the ground than it's horizontal components and this is why we hunt for those vertical components. Orienting a vertically polarized horn for horizontal polarity is simply no good outside the lab where the ground and other obstructions over distance will suck the life out of those horizontally polarized waves quickly.
I'm really not debating antenna design, but rather some folks inaccurate impressions that Vertical vs Horiztonal really doesn't matter when the source itself is Circularly polarized. It certainly does out here where the game is played.
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