Colinear antenna apparatus

Claim 2

A colinear antenna apparatus comprising, in combination: at least three dipole elements arranged in a predetermined array; each said dipole element including dipole rods as radiating arms thereof; first means for supporting said dipole elements; second means for driving said dipole elements by substantially equal and substantially in phase currents from a common feed junction at or adjacent to the center of said predetermined array; at least one coaxial cable which is substantially 360 electrical degrees in length for connecting said common feed junction to at least one of said dipole elements which is remote from said common feed junction; and said coaxial cable being disposed substantially concentrically with said dipole rods, passing through the interior of said dipole rods, and connected between said common feed junction and the driving point of the outer dipoles, with a U-shaped bend in the space between the center dipole and the outer dipole.

Claim 3

A colinear antenna apparatus substantially characterized in accordance with claim 1, wherein each said coaxial cable which is substantially 360 electrical degrees in length for connecting said common feed junction to at least one of said dipole elements which is remote from said common feed junction has a substantially ''''U'''' shape with its major portions disposed transverse to the predetermined colinear array of said dipole elements.

Claim 4

A colinear antenna apparatus characterized substantially in accordance with claim 1, wherein each said coaxial cable which is substantially 360 electrical degrees in length for connecting said common feed junction to at least one of said dipole elements which is remote from said common feed junction has the shape of a coil which is disposed transverse to the predetermined colinear array of said dipole elements.

Claim 5

A colinear antenna apparatus characterized substantially in accordance with claim 1, wherein said dipole elements are spaced apart by predetermined distances which determine the angular separation between the central maximum and the first null of the radiation pattern transmitted by said colinear antenna apparatus.

Claim 6

A colinear antenna apparatus characterized substantially in accordance with claim 1, wherein said dipole elements include three colinear half wave dipoles which are equally spaced apart and which have a non-vertical longitudinal axis, and wherein all dipole currents are equal in magnitude and phase and are properly polarized for a three element broadside array.

Claim 7

A colinear antenna apparatus characterized substantially in accordance with claim 1, including a reflector element disposed in back of said dipole elements, and wherein said reflector element may be a substantially flat reflecting screen.

Claim 8

A colinear antenna apparatus characterized substantially in accordance with claim 1, including a reflector element disposed in back of said dipole element, and wherein said reflector element is a parabolic reflector.

Claim 9

A colinear antenna apparatus characterized substantially in accordance with claim 1, including a reflector element disposed in back of said dipole elements, and wherein said reflector element is a corner reflector.

Claim 10

A colinear antenna apparatus comprising, in combination: a plurality of dipole elements arranged in a predetermined array, first means for supporting said plurality of dipole elements, second means for driving said plurality of dipole elements by sUbstantially equal and substantially in-phase current from a common feed junction at or adjacent to the center of said predetermined array, at least one conductor which is substantially 360 electrical degrees in length for connecting said common feed junction to at least one of said dipole elements which is remote from said common feed junction, said plurality of dipole elements comprises three colinear half wave dipoles which are equally spaced apart and which are arranged in a substantially horizontal predetermined array, said dipole elements being separated by a predetermined distance which determines the angular separation between the central maximum and the first null of the radiation pattern transmitted by said colinear antenna apparatus, said dipole element having dipole arms which are formed of thin walled metallic tubing, said first means for supporting said plurality of dipole elements comprising a substantially vertical mast, said plurality of dipole elements having an input impedance which is substantially equal to that of three half-wave dipoles connected in series, said second means for driving said plurality of dipole elements by substantially equal and substantially in-phase currents from a common feed junction at or adjacent to said center of said predetermined array includes a coaxial input feeder cable which is connected to a one-half wave balun transformer which changes said input impedance of said dipole elements to substantially the characteristic impedance of said coaxial cable, each said conductor which is substantially 360 electrical degrees in length for connecting said common feed junction to at least one of said dipole elements which is remote from said common feed junction passes through the interior of the metallic tubing which forms the dipole arms, said at least one conductor which is substantially 360 electrical degrees in length being formed from coaxial cable, and the substantially 360 electrical degree in length coaxial cable is disposed in the space between said dipole elements and is bent into a ''''U'''' shape to take up slack in the cables and to serve as an inductor to choke off current induced on the outside of said cables.

Claim 11

A colinear antenna apparatus comprising, in combination: a plurality of dipole elements arranged in a predetermined array, first means for supporting said plurality of dipole elements, second means for driving said plurality of dipole elements by sUbstantially equal and substantially in-phase current from a common feed junction at or adjacent to the center of said predetermined array, at least one conductor which is substantially 360 electrical degrees in length for connecting said common feed junction to at least one of said dipole elements which is remote from said common feed junction, said plurality of dipole elements comprises three colinear half wave dipoles which are equally spaced apart and which are arranged in a substantially horizontal predetermined array, said dipole elements being separated by a predetermined distance which determines the angular separation between the central maximum and the first null of the radiation pattern transmitted by said colinear antenna apparatus, said dipole element having dipole arms which are formed of thin walled metallic tubing, said first means for supporting said plurality of dipole elements comprising a substantially vertical mast, said plurality of dipole elements having an input impedance which is substantially equal to that of three half-wave dipoles connected in series, said second means for driving said plurality of dipole elements by substantially equal and substantially in-phase currents from a common feed junction at or adjacent to said center of said predetermined array includes a coaxial input feeder cable which is connected to a one-half wave balun transformer which changes said input impedance of said dipole elements to substantially the characteristic impedance of said coaxial cable, each said conductor which is substantially 360 electrical degrees in length for connecting said common feed junction to at least one of said dipole elements which is remote from said common feed junction passes through the interior of the metallic tubing which forms the dipole arms, said at least one conductor which is substantially 360 electrical degrees in length being formed from coaxial cable, and the substantially 360 electrical degree in length coaxial cable is disposed in the space between said dipole elements and is bent into a ''''U'''' shape to take up slack in the cables and to serve as an inductor to choke off current induced on the outside of said cables.

Claim 12

A colinear antenna apparatus comprising, in combination: a plurality of dipole elements arranged in a predetermined array, first means for supporting said plurality of dipole elements, second means for driving said plurality of dipole elements by substantially equal and substantially in-phase currents from a common feed junction at or adjacent to the center of said predetermined array, at least one coaxial line which is substantially 360 electrical degrees in length for connecting said common feed junction to at least one of said dipole elements which is remote from said common feed junction, said plurality of dipole elements comprising three half-wave dipoles which are equally spaced apart and which are arranged in a colinear predetermined array, said dipole elements being separated by a predetermined distance which determines the angular separation between the central maximum and the first null of the radiation pattern transmitted by said colinear antenna apparatus, said dipole elements having dipole arms which are formed of metallic tubing, said first means for supporting said plurality of dipole elements comprising a substantially vertical mast, said plurality of dipole elements having an input impedance which is substantially equal to that of three half-wave dipoles connected in series, said second means for driving said plurality of dipole elements by substantially equal and substantially in-phase currents from a common feed junction at or adjacent to said center of said predetermined array includes a coaxial input feeder cable which is connected to a one-half wave balun transformer which changes said input impedance of said dipole elements to substantially the characteristic impedance of said coaxial cable, each said coaxial line which is substantially 360 electrical degrees in length foR connecting said common feed junction to at least one of said dipole elements which is remote from said common feed junction passes through the interior of the metallic tubing which forms the dipole arms, said at least one coaxial line which is substantially 360 electrical degrees in length being formed from coaxial cable, and the substantially 360 electrical degree in length coaxial line being disposed in the space between said dipole elements and being bent into a ''''U'''' shape to take up slack in the cables and to serve as an inductor to choke off current induced on the outside of said cable.

Claim 13

A colinear antenna apparatus comprising, in combination: a plurality of dipole elements arranged in a predetermined array, first means for supporting said plurality of dipole elements, second means for driving said plurality of dipole elements by substantially equal and substantially in-phase currents from a common feed junction at or adjacent to the center of said predetermined array, at least one coaxial line which is substantially 360 electrical degrees in length for connecting said common feed junction to at least one of said dipole elements which is remote from said common feed junction, said plurality of dipole elements comprising three half-wave dipoles which are equally spaced apart and which are arranged in a colinear predetermined array, said dipole elements being separated by a predetermined distance which determines the angular separation between the central maximum and the first null of the radiation pattern transmitted by said colinear antenna apparatus, said dipole elements having dipole arms which are formed of metallic tubing, said first means for supporting said plurality of dipole elements comprising a substantially vertical mast, said plurality of dipole elements having an input impedance which is substantially equal to that of three half-wave dipoles connected in series, said second means for driving said plurality of dipole elements by substantially equal and substantially in-phase currents from a common feed junction at or adjacent to said center of said predetermined array includes a coaxial input feeder cable which is connected to a one-half wave balun transformer which changes said input impedance of said dipole elements to substantially the characteristic impedance of said coaxial cable, each said coaxial line which is substantially 360 electrical degrees in length foR connecting said common feed junction to at least one of said dipole elements which is remote from said common feed junction passes through the interior of the metallic tubing which forms the dipole arms, said at least one coaxial line which is substantially 360 electrical degrees in length being formed from coaxial cable, and the substantially 360 electrical degree in length coaxial line being disposed in the space between said dipole elements and being bent into a ''''U'''' shape to take up slack in the cables and to serve as an inductor to choke off current induced on the outside of said cable.