Microwave antenna

Claim 2

A microwave antenna having a movable feed, said microwave antenna comprising: a thin layer radiating-receiving microwave waveguide section having: 1) a conductive first plate; 2) a dielectric slab disposed on said conductive first plate and having a convex edge, positioned such that the convex edge functions as a microwave lens with respect to incident microwave radiation; 3) a conductive radiating-receiving second plate defining a radiating-receiving area, disposed on said dielectric slab, said second plate comprising a plurality of spaced apertures, said plurality of spaced apertures defining a spacing chosen to produce or define microwave beams having directions into or out of said second plate determined by directions of propagation of microwave radiation within said radiating-receiving microwave waveguide section, and wherein the feed propagates microwave radiation into, or receives microwave radiation from, an air cavity formed by said first and second conductive plates, and wherein wavefronts of the microwave radiation incident on said convex edge of the dielectric slab are made substantially parallel to each other, and wherein the horizontal direction of microwave radiation radiated from the dielectric slab is controlled by corresponding horizontal movement of the feed.

Claim 3

An antenna as in claim 1 wherein: a) said waveguide section is designed to operate within a frequency band, said band defining a highest design frequency and a lowest design wavelength, and b) said dielectric slab thickness is less than about 40% of said lowest design wavelength.

Claim 4

An antenna as in claim 1 wherein: a) said microwave lens comprises an extension of said dielectric slab having an edge defining an arc of a first circle having, a center within said slab, and b) said microwave lens is arranged, in a receiving mode, to focus microwave radiation propagating in said thin layer radiating-receiving waveguide section at a plurality of locations, each location defining a focal radiation in said thin layer radiating-receiving waveguide section, and wherein said plurality of focal locations are located on an arc of a second circle having the same center as said first circle.

Claim 5

An antenna as in claim 1, further comprising at least one transmitting-receiving microwave element for performing at least one of the following functions: 1) in the receiving mode, receiving microwave energy from said thin layer radiating-receiving microwave waveguide section focused at said plurality of focal locations, and 2) in the transmitting mode, transmitting microwave energy from said plurality of apertures into said thin layer radiating-receiving microwave section, and wherein said at least one transmitting-radiating-receiving microwave element is a microwave horn.

Claim 6

An antenna as in claim 1, wherein said plurality of apertures is at least 500 apertures.

Claim 7

An antenna as in claim 1 wherein said first plate, said dielectric slab and said radiating-receiving second plate each has a surface area of at least 10 square inches.

Claim 8

An antenna as in claim 1, further comprising at least one transmitting-receiving microwave element for performing at least one of the following functions: 1) in the receiving mode, receiving microwave energy from said thin layer radiating-receiving microwave waveguide section focused at said plurality of focal locations, and 2) in the transmitting mode, transmitting microwave energy from said plurality of apertures into said thin layer radiating-receiving microwave section, and wherein said at least one transmitting-radiating-receiving microwave element is an open ended waveguide.

Claim 9

An antenna as in claim 4 wherein said at least one transmitting-radiating-receiving microwave element is a plurality of microwave horns.

Claim 10

An antenna as in claim 1 wherein said microwave lens is a boot-lace type lens.

Claim 11

An antenna as in claim 1 wherein said microwave lens is chosen from a group of lenses consisting of: a Rottman-Turner lens an Archer lens, a geodesic lens, and a Luneburg lens.

Claim 12

An antenna as in claim 1 designed to function within a frequency band of microwave radiation defining a midpoint wavelength wherein said dielectric slab has a thickness of between about 20% and about 60% of said midpoint wavelength.

Claim 13

An antenna as in claim 7 wherein said dielectric slab has a thickness of about 40% of said midpoint wavelength.

Claim 14

A microwave antenna as in claim 1 and further comprising an imaging system for producing, from microwave radiation collected by said antenna from a field of view, images of objects in said field of view.

Claim 15

A microwave imaging system comprising: A) a microwave antenna comprised of: 1) a thin layer radiating-receiving microwave waveguide section comprised of: a) a metallic bottom plate, b) a dielectric slab disposed on said metallic bottom plate, c) a metallic radiating-receiving cover plate defining a radiating-receiving area, disposed on said dielectric slab, said cover plate comprising a plurality of spaced slots, said spaced slots defining a regular spacing chosen to produce or define microwave beams having directions into or out of said cover plate determined by directions of propagation of TEM microwave radiation within said radiating-receiving microwave waveguide section; 2) a microwave lens arranged to perform at least one of the following functions: a) in a radiating-receiving mode, focus TEM microwave radiation propagating in said thin layer radiating-receiving waveguide section at a plurality of locations, each location defining a focal location and each of said focal locations corresponding to a direction of travel to TEM microwave radiation in said thin layer radiating-receiving waveguide section, and b) in a radiating mode, to produce in said thin layer radiating-receiving waveguide section microwave beams having substantially linear wavefronts from microwave radiation from any one of said focal locations; 3) at least one transmitting-radiating-receiving microwave element for performing at least one of the following functions: 1) in a radiatin-receiving mode, radiating-receiving microwave energy from said thin layer radiating-receiving microwave waveguide section focused at said plurality of focal locations, and 2) in a transmitting mode, transmitting microwave energy from said plurality of slots into said thin layer radiating-receiving microwave section; B. a processing system comprised of: 1) front end electronics for converting microwave radiation collected by said antenna into corresponding signals at lower frequencies; 2) processor interface electronics for said lower frequency signals into a plurality of frequency subbands; and 3) a processor for converting said frequency subbands into optical images.

Claim 16

A microwave imaging system comprising: A) a microwave antenna comprised of: 1) a thin layer radiating-receiving microwave waveguide section comprised of: a) a metallic bottom plate, b) a dielectric slab disposed on said metallic bottom plate, c) a metallic radiating-receiving cover plate defining a radiating-receiving area, disposed on said dielectric slab, said cover plate comprising a plurality of spaced slots, said spaced slots defining a regular spacing chosen to produce or define microwave beams having directions into or out of said cover plate determined by directions of propagation of TEM microwave radiation within said radiating-receiving microwave waveguide section; 2) a microwave lens arranged to perform at least one of the following functions: a) in a radiating-receiving mode, focus TEM microwave radiation propagating in said thin layer radiating-receiving waveguide section at a plurality of locations, each location defining a focal location and each of said focal locations corresponding to a direction of travel to TEM microwave radiation in said thin layer radiating-receiving waveguide section, and b) in a radiating mode, to produce in said thin layer radiating-receiving waveguide section microwave beams having substantially linear wavefronts from microwave radiation from any one of said focal locations; 3) at least one transmitting-radiating-receiving microwave element for performing at least one of the following functions: 1) in a radiatin-receiving mode, radiating-receiving microwave energy from said thin layer radiating-receiving microwave waveguide section focused at said plurality of focal locations, and 2) in a transmitting mode, transmitting microwave energy from said plurality of slots into said thin layer radiating-receiving microwave section; B. a processing system comprised of: 1) front end electronics for converting microwave radiation collected by said antenna into corresponding signals at lower frequencies; 2) processor interface electronics for said lower frequency signals into a plurality of frequency subbands; and 3) a processor for converting said frequency subbands into optical images.

Claim 17

An image system as in claim 14 wherein said processor is an optical processor.

Claim 18

An imaging system as in claim 15 wherein said optical processor comprises: a) a Bragg cell, b) an acoustic transducer attached to said Bragg cell for generating diffraction gratings in said Bragg cell from signal information contained in said frequency subbands, c) a laser for producing a laser beam directed at said Bragg cell, and d) an optical detector for detecting laser radiation diffracted from said Bragg cell and forming an image from information contained in said diffracted radiation.

Claim 19

An image system as in claim 14 wherein said processor is an Archer processor.

Claim 20

A microwave antenna for radiating-receiving or transmitting microwave radiation within a frequency band defining a minimum wavelength corresponding to the highest frequency in said frequency band comprising: A) a dielectric slab defining edges, a radiating-receiving surface, and an opposite surface, and having a convex edge, such that the convex edge functions as a microwave lens; B) at least one movable transmitting-radiating-receiving microwave element for performing at least one of the following functions: 1) in a radiating-receiving mode, radiating-receiving microwave energy from at least one edge of said dielectric slab, and 2) in a transmitting mode, transmitting microwave energy into at least one edge of said dielectric slab, C) a plurality of subresonant radiating-receiving elements arranged to couple microwave energy into or out of said dielectric slab through said radiating-receiving surface; wherein said at least one movable transmitting-radiating-receiving microwave element propagates microwave radiation into, or receives microwave radiation from, an air cavity formed by said at least one edge of the dielectric slab and said at least one movable transmitting-radiating-receiving microwave element, and wherein wavefronts of the microwave radiation incident on said convex edge of the dielectric slab are made substantially parallel to each other, and wherein the horizontal direction of microwave radiation radiated from the dielectric slab is controlled by corresponding horizontal movement of said at least one movable transmitting-radiating-receiving microwave element.

Claim 21

A microwave antenna for radiating-receiving or transmitting microwave radiation within a frequency band defining a minimum wavelength corresponding to the highest frequency in said frequency band comprising: A) a dielectric slab defining edges, a radiating-receiving surface, and an opposite surface, and having a convex edge, such that the convex edge functions as a microwave lens; B) at least one movable transmitting-radiating-receiving microwave element for performing at least one of the following functions: 1) in a radiating-receiving mode, radiating-receiving microwave energy from at least one edge of said dielectric slab, and 2) in a transmitting mode, transmitting microwave energy into at least one edge of said dielectric slab, C) a plurality of subresonant radiating-receiving elements arranged to couple microwave energy into or out of said dielectric slab through said radiating-receiving surface; wherein said at least one movable transmitting-radiating-receiving microwave element propagates microwave radiation into, or receives microwave radiation from, an air cavity formed by said at least one edge of the dielectric slab and said at least one movable transmitting-radiating-receiving microwave element, and wherein wavefronts of the microwave radiation incident on said convex edge of the dielectric slab are made substantially parallel to each other, and wherein the horizontal direction of microwave radiation radiated from the dielectric slab is controlled by corresponding horizontal movement of said at least one movable transmitting-radiating-receiving microwave element.

Claim 22

An antenna as in claim 18 wherein said radiating-receiving elements comprise grooves in said dielectric slab or slots in a metal cover plate.

Claim 23

An antenna as in claim 18 wherein said radiating-receiving elements comprise patches disposed on said dielectric slab.

Claim 24

An antenna as in claim 20 wherein said patches are metal patches.

Claim 25

An antenna as in claim 20 wherein said patches are dielectric patches.

Claim 26

An antenna as in claim 18 wherein said radiating-receiving elements comprise grooves in said dielectric slab.

Claim 27

An antenna as in claim 18 designed to operate in a TEM mode wherein said dielectric slab has a thickness of less than about 50% of said minimum wavelength.

Claim 28

An antenna as in claim 18 further comprising a multi-focal microwave element defining a focal plane, said multi-focal microwave element arranged to focus microwave energy at a plurality of locations on said focal plane depending upon angles of incidence of microwave energy incident upon said dielectric slab.

Claim 29

An antenna as in claim 25 wherein said multi-focal microwave element is a dielectric lens.

Claim 30

An antenna as in claim 26 wherein said dielectric lens is a piano-convex lens.

Claim 31

An antenna as in claim 26 wherein said dielectric lens is a wide angle lens.

Claim 32

A microwave antenna for radiating-receiving or transmitting microwave radiation within a frequency band defining a minimum wavelength corresponding to the highest frequency in said frequency band, and having a feed, said microwave antenna comprising: A) a dielectric slab having a thickness of less than one-half said minimum wavelength, said slab defining edges, a radiating-receiving surface and an opposite surface, and having a convex edge, such that the convex edge functions as a microwave lens; B) at least one transmitting-radiating-receiving microwave element for performing at least one of the following functions: 1) in radiating-receiving mode, radiating-receiving microwave energy from at least one edge of said dielectric slab, and 2) in a transmitting mode, transmitting microwave energy into at least one edge of said dielectric slab, wherein the feed propagates microwave radiation into, or receives microwave radiation from, an air cavity formed by said first and second conductive plates, and wherein wavefronts of the microwave radiation incident on said convex edge of the dielectric slab are made substantially parallel to each other, and wherein the horizontal direction of microwave radiation radiated from the dielectric slab is controlled by corresponding horizontal movement of the feed.

Claim 33

A microwave antenna for radiating-receiving or transmitting microwave radiation within a frequency band defining a minimum wavelength corresponding to the highest frequency in said frequency band, and having a feed, said microwave antenna comprising: A) a dielectric slab having a thickness of less than one-half said minimum wavelength, said slab defining edges, a radiating-receiving surface and an opposite surface, and having a convex edge, such that the convex edge functions as a microwave lens; B) at least one transmitting-radiating-receiving microwave element for performing at least one of the following functions: 1) in radiating-receiving mode, radiating-receiving microwave energy from at least one edge of said dielectric slab, and 2) in a transmitting mode, transmitting microwave energy into at least one edge of said dielectric slab, wherein the feed propagates microwave radiation into, or receives microwave radiation from, an air cavity formed by said first and second conductive plates, and wherein wavefronts of the microwave radiation incident on said convex edge of the dielectric slab are made substantially parallel to each other, and wherein the horizontal direction of microwave radiation radiated from the dielectric slab is controlled by corresponding horizontal movement of the feed.

Claim 34

An antenna as in claim 29 and further comprising a plurality of subresonant radiating-receiving elements, arranged to couple microwave energy into or out of said dielectric slab through said radiating-receiving surface.

Claim 35

An antenna as in claim 30 wherein said radiating-receiving elements comprise grooves in said dielectric slab or slots in a metal cover plate.

Claim 36

An antenna as in claim 30 wherein said radiating-receiving elements comprise patches disposed on said dielectric slab.

Claim 37

An antenna as in claim 32 wherein said patches are metal patches.

Claim 38

An antenna as in claim 32 wherein said patches are dielectric patches.

Claim 39

An antenna as in claim 30 wherein said radiating-receiving elements comprise grooves in said dielectric slab.

Claim 40

An antenna as in claim 30 and further comprising a multi-focal microwave element defining a focal plane, said multi-focal microwave element arranged to focus microwave energy at a plurality of locations on said focal plane depending upon angles of incidence of microwave energy incident upon said dielectric slab.

Claim 41

An antenna as in claim 36 wherein said multi-focal microwave element is a dielectric lens.

Claim 42

An antenna as in claim 36 wherein said dielectric lens is a plano-convex lens.

Claim 43

An antenna as in claim 36 wherein said dielectric lens is a wide angle lens.

Claim 44

A microwave antenna having a feed including a microwave lens, comprising: a thin layer radiating-receiving microwave waveguide section having: 1) a conductive first plate; 2) a dielectric slab disposed on said conductive first plate, and having a convex edge, such that the convex edge functions as a microwave lens; 3) a conductive radiating-receiving second plate defining a radiating-receiving area, disposed on said dielectric slab, said second plate comprising a plurality of spaced slots, said plurality of spaced slots defining a spacing chosen to produce or define microwave beams having directions into or out of said second plate determined by directions of propagation of microwave radiation within said radiating-receiving microwave waveguide section, and wherein said waveguide section is designed to operate within a frequency band, said band defining a highest design frequency and a lowest design wavelength, and wherein the feed propagates microwave radiation into, or receives microwave radiation from, an air cavity formed by said first and second conductive plates, and wherein wavefronts of the microwave radiation incident on said convex edge of the dielectric slab are made substantially parallel to each other, and wherein the horizontal direction of microwave radiation radiated from the dielectric slab is controlled by corresponding horizontal movement of the feed.

Claim 45

A microwave antenna having a feed including a microwave lens, comprising: a thin layer radiating-receiving microwave waveguide section having: 1) a conductive first plate; 2) a dielectric slab disposed on said conductive first plate, and having a convex edge, such that the convex edge functions as a microwave lens; 3) a conductive radiating-receiving second plate defining a radiating-receiving area, disposed on said dielectric slab, said second plate comprising a plurality of spaced slots, said plurality of spaced slots defining a spacing chosen to produce or define microwave beams having directions into or out of said second plate determined by directions of propagation of microwave radiation within said radiating-receiving microwave waveguide section, and wherein said waveguide section is designed to operate within a frequency band, said band defining a highest design frequency and a lowest design wavelength, and wherein the feed propagates microwave radiation into, or receives microwave radiation from, an air cavity formed by said first and second conductive plates, and wherein wavefronts of the microwave radiation incident on said convex edge of the dielectric slab are made substantially parallel to each other, and wherein the horizontal direction of microwave radiation radiated from the dielectric slab is controlled by corresponding horizontal movement of the feed.

Claim 46

A microwave antenna for receiving or transmitting microwave radiation within a frequency band defining a minimum wavelength corresponding to the highest frequency in said frequency band comprising: A) a dielectric slab defining edges, a radiating-receiving surface, and an opposite surface, and having a convex edge, such that the convex edge functions as a microwave lens; B) at least one transmitting-receiving microwave element for performing at least one of the following functions: 1) in a receiving mode, receiving microwave energy from at least one edge of said dielectric slab, and 2) in a transmitting mode, transmitting microwave energy into at least one edge of said dielectric slab, wherein a feed propagates microwave radiation into, or receives microwave radiation from, an air cavity formed by first and second conductive plates, and wherein wavefronts of the microwave radiation incident on said convex edge of the dielectric slab are made substantially parallel to each other, and wherein the horizontal direction of microwave radiation radiated from the dielectric slab is controlled by corresponding horizontal movement of the feed; C) a plurality of radiating-receiving elements, each element having a major dimension less than about 40% of said minimum wavelength and arranged to couple microwave energy into or out of said dielectric slab through said radiating-receiving surface.

Claim 47

A microwave antenna for receiving or transmitting microwave radiation within a frequency band defining a minimum wavelength corresponding to the highest frequency in said frequency band comprising: A) a dielectric slab defining edges, a radiating-receiving surface, and an opposite surface, and having a convex edge, such that the convex edge functions as a microwave lens; B) at least one transmitting-receiving microwave element for performing at least one of the following functions: 1) in a receiving mode, receiving microwave energy from at least one edge of said dielectric slab, and 2) in a transmitting mode, transmitting microwave energy into at least one edge of said dielectric slab, wherein a feed propagates microwave radiation into, or receives microwave radiation from, an air cavity formed by first and second conductive plates, and wherein wavefronts of the microwave radiation incident on said convex edge of the dielectric slab are made substantially parallel to each other, and wherein the horizontal direction of microwave radiation radiated from the dielectric slab is controlled by corresponding horizontal movement of the feed; C) a plurality of radiating-receiving elements, each element having a major dimension less than about 40% of said minimum wavelength and arranged to couple microwave energy into or out of said dielectric slab through said radiating-receiving surface.

Claim 48

A microwave antenna having a feed including a microwave lens, comprising: a thin layer radiating-receiving microwave waveguide section having: 1) a conductive first plate; 2) a dielectric slab disposed on said conductive first plate, and having a convex edge, such that the convex edge functions as a microwave lens; 3) a conductive radiating-receiving second plate defining a radiating-receiving area, disposed on said dielectric slab, said second plate comprising a plurality of spaced apertures, said plurality of spaced apertures defining a spacing chosen to produce or define microwave beams having directions into or out of said second plate determined by directions of propagation of microwave radiation within said radiating-receiving microwave waveguide section, and wherein the feed propagates microwave radiation into, or receives microwave radiation from, an air cavity formed by said first and second conductive plates, and wherein wavefronts of the microwave radiation incident on said convex edge of the dielectric slab are made substantially parallel to each other, and wherein the horizontal direction of microwave radiation radiated from the dielectric slab is controlled by corresponding horizontal movement of the feed.

Claim 49

A microwave antenna having a feed including a microwave lens, comprising: a thin layer radiating-receiving microwave waveguide section having: 1) a conductive first plate; 2) a dielectric slab disposed on said conductive first plate, and having a convex edge, such that the convex edge functions as a microwave lens; 3) a conductive radiating-receiving second plate defining a radiating-receiving area, disposed on said dielectric slab, said second plate comprising a plurality of spaced apertures, said plurality of spaced apertures defining a spacing chosen to produce or define microwave beams having directions into or out of said second plate determined by directions of propagation of microwave radiation within said radiating-receiving microwave waveguide section, and wherein the feed propagates microwave radiation into, or receives microwave radiation from, an air cavity formed by said first and second conductive plates, and wherein wavefronts of the microwave radiation incident on said convex edge of the dielectric slab are made substantially parallel to each other, and wherein the horizontal direction of microwave radiation radiated from the dielectric slab is controlled by corresponding horizontal movement of the feed.