Slot antenna array

Claim 2

An antenna for signals of a given frequency, compriSing conductive means defining a slot therein having a longitudinal dimension, a transmission line electrically connected to said slot at a predetermined point along said longitudinal dimension, and means in operative relation to said slot for causing all radiation relative to said antenna to be associated only with sections of said slot of like field polarity without significantly affecting the phase velocity of the signals as they pass from said predetermined point to all other points along said slot, said means comprising additional slots defined by said conductive means, each additional slot having a longitudinal dimension normal to said first mentioned slot at half-wavelength intervals therealong and extending a quarter-wavelength therefrom on each side thereof, the intersection of each of said additional slots with said first mentioned slot defining four corner portions in said conductive means at each respective intersection, and discrete conductors coupling together the respective diagonally opposite pairs of corner portions at each of said intersections so that a field distribution is established along said first mentioned slot having the same field polarity over each successive half-wavelength section thereof, and whereby said antenna functions as a plural slot array in operation with only a single transmission line.

Claim 3

The antenna of claim 1 wherein said transmission line is connected at the center of a half-wavelength section of said first mentioned slot.

Claim 4

The antenna of claim 1 wherein said conductive means comprises a metal plate.

Claim 5

The antenna of claim 3 wherein said metal plate is folded along the longitudinal dimension of said first mentioned slot.

Claim 6

An antenna assembly for transmitting signals of a given frequency, comprising an elongated electrically conductive supporting structure having a longitudinal axis and a major transverse dimension at least a quarter-wavelength at said given frequency, conductive means defining a continuous slot on said supporting structure, said slot having a longitudinal dimension parallel to the longitudinal axis of said supporting structure, a transmission line electrically connected to said slot at a predetermined point along said longitudinal dimension for exciting said slot with said given frequency signals from a source, means in operative relation to said slot for causing all radiation therefrom to be emitted from sections of said slot of like field polarity without significantly affecting the phase velocity of the signals as they pass from said predetermined point to all other points along said slot, said means comprising additional slots defined by said conductive means, each additional slot having a longitudinal dimension normal to said first mentioned slot at half-wavelength intervals therealong and extending a quarter-wavelength therefrom on each side thereof, the intersection of each of said additional slots with said first mentioned slot defining four corner portions in said conductive means at each respective intersection, discrete conductors coupling together the respective diagonally opposite pairs of corner portions at each of said intersections so that a field distribution is established along said first mentioned slot having the same field polarity over each successive half-wavelength section thereof, at least one end-fire parasitic director comprising a plurality of discrete conductive members disposed in spaced parallel relation along an axis transverse to said conductive members, said discrete conductive members having a respective dimension in the plane of the electric field vector of the transmitted signals, and said end-fire parasitic director being so positioned relative to said first mentioned slot and supporting structure as to alter the shape of the antenna pattern produced by the combined effects of said slot and supporting structure, while not intersecting the radiation axis of the radiating slot sections, to provide a selected pattern for said antenna assembly, and said antenna assembly functioning as a plural slot array fed from only a single transmission line.

Claim 7

An antenna assembly for transmitting signals of a given frequency, comprising an elongated electrically conductive supporting structure having a longitudinal axis and a major transverse dimension at least a quarter-wavelength at said given frequency, conductive means defining a continuous slot on said supporting structure, said slot having a longitudinal dimension parallel to the longitudinal axis of said supporting structure, a transmission line electrically connected to said slot at a predetermined point along said longitudinal dimension for exciting said slot with said given frequency signals from a source, means in operative relation to said slot for causing all radiation therefrom to be emitted from sections of said slot of like field polarity without significantly affecting the phase velocity of the signals as they pass from said predetermined point to all other points along said slot, said means comprising additional slots defined by said conductive means, each additional slot having a longitudinal dimension normal to said first mentioned slot at half-wavelength intervals therealong and extending a quarter-wavelength therefrom on each side thereof, the intersection of each of said additional slots with said first mentioned slot defining four corner portions in said conductive means at each respective intersection, discrete conductors coupling together the respective diagonally opposite pairs of corner portions at each of said intersections so that a field distribution is established along said first mentioned slot having the same field polarity over each successive half-wavelength section thereof, at least one end-fire parasitic director comprising a plurality of discrete conductive members disposed in spaced parallel relation along an axis transverse to said conductive members, said discrete conductive members having a respective dimension in the plane of the electric field vector of the transmitted signals, and said end-fire parasitic director being so positioned relative to said first mentioned slot and supporting structure as to alter the shape of the antenna pattern produced by the combined effects of said slot and supporting structure, while not intersecting the radiation axis of the radiating slot sections, to provide a selected pattern for said antenna assembly, and said antenna assembly functioning as a plural slot array fed from only a single transmission line.

Claim 8

The antenna of claim 5 wherein said conductive means comprises a metal plate, said plate being folded along the longitudinal dimension of said first mentioned slot toward the supporting structure to define the radiation axis for the radiating slot sections directed away from the supporting structure.

Claim 9

The antenna of claim 5 wherein said predetermined point of connection of said transmission line is at the center of a half-wavelength slot section of said first mentioned slot.

Claim 10

The antenna assembly of claim 5 wherein the longitudinal axis of said supporting structure is vertical, and said predetermined point of connection of said transmission line is at the center of the lowest half-wavelength slot section of the antenna assembly.

Claim 11

An antenna for signals of a given frequency, comprising conductive means defining a slot therein having a longitudinal dimension, a transmission line electrically connected to said slot at a predetermined point along said longitudinal dimension, additional slots defined by said conductive means, each additional slot having a longitudinal dimension normal to said first mentioned slot at half-wavelength intervals therealong and extending a quarter-wavelength therefrom on each side thereof, the intersection of each of said additional slots with said first mentioned slot defining four corner portions in said conductive means at each respective intersection, discrete conductors coupling together the respective diagonally opposite pairs of corner portions at each of said intersections so that a field distribution is established along said first mentioned slot having the same field polarity over each successive half-wavelength section thereof, whereby said antenna functions as a plural slot array in operation with only a single transmission line.

Claim 12

An antenna for signals of a given frequency, comprising conductive means defining a slot therein having a longitudinal dimension, a transmission line electrically connected to said slot at a predetermined point along said longitudinal dimension, additional slots defined by said conductive means, each additional slot having a longitudinal dimension normal to said first mentioned slot at half-wavelength intervals therealong and extending a quarter-wavelength therefrom on each side thereof, the intersection of each of said additional slots with said first mentioned slot defining four corner portions in said conductive means at each respective intersection, discrete conductors coupling together the respective diagonally opposite pairs of corner portions at each of said intersections so that a field distribution is established along said first mentioned slot having the same field polarity over each successive half-wavelength section thereof, whereby said antenna functions as a plural slot array in operation with only a single transmission line.