Monopulse cavity-backed multipole antenna system
First Claim
1. An antenna system comprising:
- a substantially cylindrical cavity defined by a conductive enclosure and having a center axis;
N radiation elements comprising substantially identical, substantially planar, non-interleaved elements of a polygon shape arranged in a closely packed, substantially symmetrical configuration about the axis of said cavity and adapted for communicating right circularly polarized (RCP) and left circularly polarized (LCP) electromagnetic energy wherein N is no less than six; and
difference signal means coupled thereto for providing an antenna system difference pattern characterized by substantial symmetry in space about the antenna boresight.
2 Assignments
0 Petitions
Accused Products
Abstract
A cylindrical cavity-backed multipole antenna system for high frequency applications is disclosed. The antenna system comprises a plurality N of planar radiation elements disposed on a dielectric disc mounted on the top surface of a conductive cylindrical cavity and equally spaced about its axis. A network circuit is adapted to introduce, for the system sum signal, progressive phase shifts of 360°/N to signals associated with adjacent elements and, for the difference signal, progressive phase shifts of 720°/N. The antenna system may be used to both transmit and receive electromagnetic radiation. The antenna sum and difference patterns are substantially symmetric in space about the antenna boresight.
-
Citations
28 Claims
-
1. An antenna system comprising:
-
a substantially cylindrical cavity defined by a conductive enclosure and having a center axis; N radiation elements comprising substantially identical, substantially planar, non-interleaved elements of a polygon shape arranged in a closely packed, substantially symmetrical configuration about the axis of said cavity and adapted for communicating right circularly polarized (RCP) and left circularly polarized (LCP) electromagnetic energy wherein N is no less than six; and difference signal means coupled thereto for providing an antenna system difference pattern characterized by substantial symmetry in space about the antenna boresight. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
-
-
14. In a cylindrical cavity-backed antenna system having N radiation elements disposed adjacent the top surface of the cavity and spaced about a center axis of the cavity, and a feed system coupled to such elements, the improvement comprising:
-
N is at least six; the radiation elements comprise substantially identical, substantially planar, non-interleaved elements of a polygon shape arranged in a closely packed, substantially symmetrical configuration about the axis of said cavity; and network circuit means coupled to the feed means for producing an antenna system sum signal and an antenna system difference signal. - View Dependent Claims (15, 16, 17, 18, 19, 20, 27)
-
-
21. An antenna system comprising:
-
first and second coaxially disposed conductive cylinders of a first diameter and a second diameter, each having first end regions, the first end regions of said cylinders being in substantial transverse alignment; a first transverse conductive member disposed across and conductively joined across said first cylinder so as to define a first cavity inside said first conductive cylinder; an annular second transverse conductive member disposed laterally between and conductively joined to said first and second conductive cylinders so as to define a second cavity in the annular region between said first and second cylinders; a first set of N conductive radiation elements extending outwardly in a general radial direction from the center axis of said first cavity toward the adjacent first cylinder and generally equally spaced from adjacent elements, said radiation elements being insulated from said cylinders and being substantially parallel to the plane formed by said first end region of said first conductive cylinder, wherein N is at least six; a second set of P conductive radiation elements extending outwardly in a general radial direction from adjacent the first cylinder toward the second cylinder, said radiation elements being insulated from said cylinders and being substantially parallel to the plane formed by said first end region of said second cylinder, wherein P is at least six; difference signal means coupled to said first set of radiation elements and arranged to produce one difference signal characterized by a difference signal pattern which is substantially symmetrical in space about the angenna boresight; and second difference signal means coupled to said second set of radiation elements and arranged to produce a second difference signal characterized by a difference signal pattern which is substantially symmetrical in space about the antenna boresight. - View Dependent Claims (22, 23, 24, 25, 28)
-
-
26. An antenna system comprising:
-
a plurality of coaxially disposed conductive cylinders of progressively larger diameters, each having first and second end regions, the first end regions of said cylinders being in substantial transverse alignment. a plurality of transverse conductive members disposed across and conductively joined to said cylinders defining a cylindrical inner cavity and annular outer cavities. a plurality of sets of conductive radiation elements disposed generally on concentric rings, the first set equally spaced about the center axis of the cylinders and extending generally radially outward above said inner cavity, and the succeeding rings respectively equally spaced and extending generally radially outwardly above the successive annular cavities each set having at least six radiation elements; and a plurality of difference signal means coupled respectively to each set of radiation elements and arranged to produce a plurality of difference signals each characterized by a difference signal pattern having substantial symmetry about the antenna system boresight.
-
Specification