Circularly polarized broadcast antenna

Claim 2

A broadcast antenna for radiating a circularly polarized wave, said antenna being resonant at a wavelength lambda and comprising a conducting mast, a plurality of radiators mounted on said mast at intervals lambda , and a transmission line coupled to said radiators, each radiator comprising insulating means connected to the mast, a pair of conducting arms each connected at one end to said insulating means, said arms being formed intermediate their ends into a horizontally radiating loop section in a plane normal to the mast, said horizontally radiating section having a perimeter of approximately lambda /2 and being interrupted by the insulating means and by a gap between the arms on the side of the loop opposite the insulating means, said arms terminating in sections extending from said plane in opposite directions to form a dipole approximately lambda /4 in length, and means for coupling said transmission line to said arms.

Claim 3

An electromagnetic radiator resonant at a wavelength lambda and comprising an insulating support and a pair of conducting arms each connected at one end to said insulating support, said arms being formed intermediate their ends into an interrupted loop in a first plane, said loop having a perimeter of approximately lambda /2 and comprising a first pair of parallel sides, one interrupted by said insulating support and the other interrupted by a gap between the arms, said loop comprising a second pair of parallel conducting sides, said arms terminating in sections extending out of said first plane in different directions in parallel planes normal to said first plane to form a dipole approximately lambda /4 in length.

Claim 4

An electromagnetic radiator resonant at a wavelength lambda and comprising an insulating support and a pair of conducting arms each connected at one end to said insulating support, said arms being formed intermediate their ends into an interrupted loop in a first plane, said loop having a perimeter of approximately lambda /2 and comprising a first pair of parallel sides, one interrupted by said insulating support and the other interrupted by a gap between the arms, said loop comprising a second pair of parallel conducting sides, said arms terminating in sections extending out of said first plane in different directions in parallel planes normal to said first plane to form a dipole approximately lambda /4 in length.

Claim 5

An antenna resonant at a wavelength lambda and comprising a conducting backplate, a first pair of conducting plates electrically and mechAnically connected to the backplate and extending normal to the backplate in spaced parallel relation, an insulator mounted on the backplate, a second pair of conducting plates, each of said second pair of plates being mounted on the insulator in spaced parallel confronting relation to a different one of the first pair of plates to form two capacitors having a common terminal formed by the backplate, and a pair of conducting arms each electrically and mechanically connected at one end to a different one of said second pair of plates, said arms being formed intermediate their ends into an interrupted loop in a first plane, said loop having a perimeter of approximately lambda /2, and being interrupted by said capacitor and by a gap between the arms, said arms terminating in sections extending from the loop at said gap in different directions parallel to a second plane normal to said first plane to form a dipole.

Claim 6

An antenna resonant at a wavelength lambda and comprising a conducting backplate, a first pair of conducting plates electrically and mechAnically connected to the backplate and extending normal to the backplate in spaced parallel relation, an insulator mounted on the backplate, a second pair of conducting plates, each of said second pair of plates being mounted on the insulator in spaced parallel confronting relation to a different one of the first pair of plates to form two capacitors having a common terminal formed by the backplate, and a pair of conducting arms each electrically and mechanically connected at one end to a different one of said second pair of plates, said arms being formed intermediate their ends into an interrupted loop in a first plane, said loop having a perimeter of approximately lambda /2, and being interrupted by said capacitor and by a gap between the arms, said arms terminating in sections extending from the loop at said gap in different directions parallel to a second plane normal to said first plane to form a dipole.

Claim 7

The antenna of claim 3, in which the portions of the arms forming the interrupted loop each comprise a pair of parallel conductors shunted at their ends and disposed in a surface normal to said first plane, and the portions of the arms forming the dipole each comprise a pair of parallel conductors shunted at their ends and disposed in planes parallel to said second plane.

Claim 8

The antenna of claim 4, further comprising a tubular conducting shield electrically and mechanically connected to said backplate, forming a passage through said backplate, and protruding toward said gap in the plane of said loop, a metal conductor extending through said shield, insulating means for supporting said metal conductor in said shield in insulated relation to said shield, means for electrically connecting said metal conductor to a point on one of said arms in said first plane, whereby said antenna will resonate and transmit radiation in response to alternating voltage having the wavelength lambda applied between said metal conductor and said backplate.

Claim 9

The antenna of claim 4, in which each conductor of each of said pairs of parallel conductors comprises a hollow metal tube, and further comprising means on each arm forming passages between the tubes forming the loop and the tubes forming the dipole, a pair of hollow metal tubes each connected between the backplate and a different one of the arms, the connections between the last recited tubes and the arms each being a connection forming a communicating passage into one of the tubes forming the loop at a point on one of said second pair of parallel sides, and electrical heating means extending through all of said tubes and terminating at common energization terminals insulated from and adjacent to said backplate.

Claim 10

An antenna for operation at the wavelength lambda , comprising insulating means, a pair of conducting arms each connected to said insulating means and formed intermediate its ends into an interrupted loop in a first plane, said loop having a perimeter of approximately lambda /2, said loop being interrupted on one side by said insulating means and on an opposite side by a gap between the arms in said first plane, said arms terminating in sections of equal length extending from said first plane in different directions parallel to a second plane normal to said first plane to form a dipole, each of said sections being approximately lambda /8 long.

Claim 11

An antenna for operation at the wavelength lambda , comprising insulating means, a pair of conducting arms each connected to said insulating means and formed intermediate its ends into an interrupted loop in a first plane, said loop having a perimeter of approximately lambda /2, said loop being interrupted on one side by said insulating means and on an opposite side by a gap between the arms in said first plane, said arms terminating in sections of equal length extending from said first plane in different directions parallel to a second plane normal to said first plane to form a dipole, each of said sections being approximately lambda /8 long.

Claim 12

The antenna of claim 7, further comprising a pair of capacitors connected in series between the ends of said arms connected to said insulating means, and means for applying a radio frequency voltage from a transmission line between the junction of said capacitors and a point on one arm in said loop.

Claim 13

The antenna of claim 7, in which the portions of said arms forming said dipole are adjustably connected to the portions of said arms forming said loop for rotation in arcs parallel to said second plane, and further comprising means connected to each arm for securing it in its adjusted position.

Claim 14

The antenna of claim 7, in which the portion of said arms Forming the loop each comprise a pair of parallel conductors shunted at their ends and disposed in a surface normal to said second plane, and in which the portions of said arms forming said dipole each comprise a pair of parallel conductors shunted at their ends and disposed in a plane parallel to said second plane.