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US5268701A Expired / Lapsed US ⏱️ 0.0 years remaining

Radio frequency antenna

Assignee: OL Security LLC
•
Filing: 1993-02-09
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Granted: 1993-12-07
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Expires: 2013-02-09
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Abstract

Abstract An improved dual polarized antenna element for use in planar array antennas. The antenna element includes a conductive sheet having a forwardly positioned notch and a pair of spaced rearwardly extending slot portions formed therein. The notch is adapted for coupling radio frequency energy between free space and the antenna element and the pair of slot portions are electrically coupled to the notch. A power divider/combiner is provided and is preferably interconnected with a power combiner/divider through branches of equal phase length. With this arrangement, reactive power divider induced off-axis scan blindness caused by an odd mode coupled field is prevented. Additionally, an antenna module comprising a pair of such antenna elements disposed in intersecting relationship is provided with a coincident phase center.

Inventors

  • 👤 Keith C. Smith

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 13:19
CPC Classifications
H; H01; H01Q; H01Q13/00; H01Q13/08; H01Q13/085; H01Q21/00; H01Q21/24

Claims Analysis

Total Claims: 19
Claim 1
Independent Claim 63 words
An antenna element comprising: a conductive sheet having formed therein a forwardly positioned notch adapted for coupling radio frequency energy between free space and the antenna element and a pair of spaced, rearwardly extending slot portions, each of said slot portions having opposing sides, each of said sides being formed by said conductive sheet, said slot portions being electrically coupled to said notch.
Claim 2
Dependent Claim 63 words
An antenna element comprising: a conductive sheet having formed therein a forwardly positioned notch adapted for coupling radio frequency energy between free space and the antenna element and a pair of spaced, rearwardly extending slot portions, each of said slot portions having opposing sides, each of said sides being formed by said conductive sheet, said slot portions being electrically coupled to said notch.
Claim 3
Dependent Claim 55 words
The antenna element recited in claim 1 further comprising: a radio frequency feed comprising a pair of spaced feed branches, with each one of said pair of feed branches having a first end coupled to a port of said radio frequency feed and a second end coupled to a corresponding one of said slot portions.
Claim 4
Dependent Claim 136 words
An antenna element comprising: a conductive sheet having formed therein a forwardly positioned notch adapted for coupling radio frequency energy between free space and the antenna element and a pair of spaced, rearwardly extending slot portions electrically coupled to said notch; a radio frequency feed comprising a pair of spaced feed branches, with each one of said pair of feed branches having a first end coupled to a port of said radio frequency feed and a second end coupled to a corresponding one of said slot portions; said radio frequency feed further comprising a power divider/combiner having an input/output port coupled to said port of said radio frequency feed and a pair of output/input ports, with each one of said pair of output/input ports being coupled to a corresponding one of said pair of feed branches.
Claim 5
Dependent Claim 136 words
An antenna element comprising: a conductive sheet having formed therein a forwardly positioned notch adapted for coupling radio frequency energy between free space and the antenna element and a pair of spaced, rearwardly extending slot portions electrically coupled to said notch; a radio frequency feed comprising a pair of spaced feed branches, with each one of said pair of feed branches having a first end coupled to a port of said radio frequency feed and a second end coupled to a corresponding one of said slot portions; said radio frequency feed further comprising a power divider/combiner having an input/output port coupled to said port of said radio frequency feed and a pair of output/input ports, with each one of said pair of output/input ports being coupled to a corresponding one of said pair of feed branches.
Claim 6
Dependent Claim 80 words
The antenna element recited in claim 3 wherein said antenna element further comprises a bifurcated slot comprising said pair of slot portions and a main slot portion disposed at the rear of said notch, and said antenna element further comprising a power combiner/divider having an output/input port coupled to said main slot portion and a pair of input/output ports, with each one of said pair of input/output ports being coupled to a corresponding one of said pair of slot portions.
Claim 7
Dependent Claim 17 words
The antenna element recited in claim 4 wherein said radio frequency feed comprises a stripline transmission line.
Claim 8
Dependent Claim 17 words
The antenna element recited in claim 4 wherein said radio frequency feed comprises a coaxial transmission line.
Claim 9
Dependent Claim 15 words
The antenna element recited in claim 4 wherein said bifurcated slot comprises a slotline circuit.
Claim 10
Dependent Claim 17 words
The antenna element recited in claim 4 wherein said radio frequency feed comprises a microstrip transmission line.
Claim 11
Dependent Claim 258 words
A radio frequency antenna module comprising: a first planar antenna element having a first line of intersection extending from a forward edge to a rearward edge thereof, said antenna element comprising a conductive sheet having formed therein a notch and a pair of spaced, rearwardly extending slot portions, each of said slot portions having opposing sides, each of said sides being formed by said conductive sheet said slot portions being electrically coupled to said notch, said notch being disposed along said forward edge of said first antenna element and being intersected by said first line of intersection, wherein each one of said pair of slot portions is disposed on an opposite side of said first line of intersection; and a second planar antenna element having a second line of intersection extending from a forward edge to a rearward edge thereof, said antenna element comprising a conductive sheet having formed therein a notch and a pair of spaced, rearwardly extending slot portions, each of said slot portions having opposing sides, each of said sides being formed by said conductive sheet said slot portions being electrically coupled to said notch, said notch being disposed along said forward edge of said second antenna element and being intersected by said second line of intersection, wherein each one of said pair of slot portions is disposed on an opposite side of said second line of intersection; and wherein said first antenna element and said second antenna element are disposed to intersect at the first line of intersection and said second line of intersection.
Claim 12
Dependent Claim 258 words
A radio frequency antenna module comprising: a first planar antenna element having a first line of intersection extending from a forward edge to a rearward edge thereof, said antenna element comprising a conductive sheet having formed therein a notch and a pair of spaced, rearwardly extending slot portions, each of said slot portions having opposing sides, each of said sides being formed by said conductive sheet said slot portions being electrically coupled to said notch, said notch being disposed along said forward edge of said first antenna element and being intersected by said first line of intersection, wherein each one of said pair of slot portions is disposed on an opposite side of said first line of intersection; and a second planar antenna element having a second line of intersection extending from a forward edge to a rearward edge thereof, said antenna element comprising a conductive sheet having formed therein a notch and a pair of spaced, rearwardly extending slot portions, each of said slot portions having opposing sides, each of said sides being formed by said conductive sheet said slot portions being electrically coupled to said notch, said notch being disposed along said forward edge of said second antenna element and being intersected by said second line of intersection, wherein each one of said pair of slot portions is disposed on an opposite side of said second line of intersection; and wherein said first antenna element and said second antenna element are disposed to intersect at the first line of intersection and said second line of intersection.
Claim 13
Dependent Claim 23 words
The radio frequency antenna module recited in claim 9 further comprising a back panel disposed perpendicular to said first and second antenna elements.
Claim 14
Dependent Claim 37 words
The radio frequency antenna module recited in claim 9 wherein said first line of intersection bisects said notch of said first antenna element and said second line of intersection bisects said notch of said second antenna element.
Claim 15
Dependent Claim 22 words
The radio frequency antenna module recited in claim 9 wherein the first and second antenna elements are disposed orthogonal to one another.
Claim 16
Dependent Claim 361 words
A radio frequency antenna module comprising: a first planar antenna element having a first line of intersection extending from a forward edge to a rearward edge thereof, said antenna element comprising a conductive sheet having formed therein a notch and a pair of spaced, rearwardly extending slot portions electrically coupled to said notch, said notch being disposed along said forward edge of said first antenna element and being intersected by said first line of intersection, wherein each one of said pair of slot portions is disposed on an opposite side of said first line of intersection; a second planar antenna element having a second line of intersection extending from a forward edge to a rearward edge thereof, said antenna element comprising a conductive sheet having formed therein a notch and a pair of spaced, rearwardly extending slot portions electrically coupled to said notch, said notch being disposed along said forward edge of said second antenna element and being intersected by said second line of intersection, wherein each one of said pair of slot portions is disposed on an opposite side of said second line of intersection; said first antenna element and said second antenna element being disposed to intersect at the first line of intersection and said second line of intersection; and said first antenna element further comprising a radio frequency feed comprising a pair of spaced feed branches, with a first end of each of said pair of feed branches being coupled to a port of said radio frequency feed of said first antenna element and a second end of each of said pair of feed branches being coupled to a corresponding one of said pair of slot portions of said first antenna element and wherein said second antenna element further comprises a radio frequency feed comprising a pair of spaced feed branches with a first end of each of said pair of feed branches being coupled to a port of said second radio frequency feed of said second antenna element and a second end of each of said pair of feed branches being coupled to a corresponding one of said pair of slot portions of said second antenna element.
Claim 17
Dependent Claim 361 words
A radio frequency antenna module comprising: a first planar antenna element having a first line of intersection extending from a forward edge to a rearward edge thereof, said antenna element comprising a conductive sheet having formed therein a notch and a pair of spaced, rearwardly extending slot portions electrically coupled to said notch, said notch being disposed along said forward edge of said first antenna element and being intersected by said first line of intersection, wherein each one of said pair of slot portions is disposed on an opposite side of said first line of intersection; a second planar antenna element having a second line of intersection extending from a forward edge to a rearward edge thereof, said antenna element comprising a conductive sheet having formed therein a notch and a pair of spaced, rearwardly extending slot portions electrically coupled to said notch, said notch being disposed along said forward edge of said second antenna element and being intersected by said second line of intersection, wherein each one of said pair of slot portions is disposed on an opposite side of said second line of intersection; said first antenna element and said second antenna element being disposed to intersect at the first line of intersection and said second line of intersection; and said first antenna element further comprising a radio frequency feed comprising a pair of spaced feed branches, with a first end of each of said pair of feed branches being coupled to a port of said radio frequency feed of said first antenna element and a second end of each of said pair of feed branches being coupled to a corresponding one of said pair of slot portions of said first antenna element and wherein said second antenna element further comprises a radio frequency feed comprising a pair of spaced feed branches with a first end of each of said pair of feed branches being coupled to a port of said second radio frequency feed of said second antenna element and a second end of each of said pair of feed branches being coupled to a corresponding one of said pair of slot portions of said second antenna element.
Claim 18
Dependent Claim 134 words
The radio frequency antenna module recited in claim 13 wherein said first antenna element further comprises a power divider/combiner having an input/output port coupled to said port of said radio frequency feed of said first antenna element and a pair of output/input ports, each one of said output/input ports being coupled to a corresponding one of said pair of feed branches of the radio frequency feed of said first antenna element and wherein aid second antenna element further comprises a power divider/combiner having an input/output port coupled to said port of said radio frequency feed of said second antenna element and a pair of output/input ports, each one of said output/input ports being coupled to a corresponding one of the pair of feed branches of the radio frequency feed of said second antenna element.
Claim 19
Dependent Claim 114 words
The radio frequency antenna module recited in claim 14 wherein said first antenna element further comprises a power combiner/divider having an output/input port coupled to said first antenna element notch and a pair of input/output ports each one of said pair of input/output ports being coupled to a corresponding one of the pair of slot portions of the first antenna element and wherein said second antenna element further comprises a power combiner/divider having an output/input port coupled to said second antenna element notch and a pair of input/output ports, each one of said pair of input/output ports being coupled to a corresponding one of the pair of slot portions of the second antenna element.

References Cited (Backward Citations)

US3836976A Cited
US4001834A Cited
JPS55128903A Cited
US4905013A Cited
US4853704A Cited
US4978965A Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-12-06 1997-06-07 1997-12-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-12-06 2001-06-07 2001-12-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-12-06 2005-06-07 2005-12-07 $7700.00 Window Closed / Lapsed

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