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US5384575A Expired / Lapsed US ⏱️ 0.0 years remaining

Bandpass frequency selective surface

Assignee: Raytheon Co
•
Filing: 1988-09-26
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Granted: 1995-01-24
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Expires: 2008-09-26
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Abstract

Abstract An improved bandpass frequency selective surface is disclosed which provides a wide pass band and reflection band with low loss at varying angles of incidence, low cost, low volume and light weight. The improved bandpass frequency selective surface of the present invention includes a mesh-patch array 10 disposed on at least a portion of a surface wherein the mesh-patch array 10 includes a square grid 12 surrounding numerous squares 20, 21, 22 and 23. A specific teaching of the invention concerns the design of the elements of a mesh-patch array 10 such that the frequency selective surface transmits or reflects the desired microwave signals.

Inventors

  • 👤 Te-Kao Wu

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 15:46
CPC Classifications
H; H01; H01Q; H01Q15/00; H01Q15/0006; H01Q15/0013

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 263 words
An improved frequency selective surface comprising: a square grid composed of a first plurality of lines of material having a first conductivity perpendicularly intersecting a second plurality of lines of material having said first conductivity so as to provide a plurality of square spaces therebetween, each of said plurality of lines having a spacing D, the distance from the beginning of a line of said first plurality of lines to the beginning of an adjacent line of said first plurality of lines and the distance from the beginning of a line of said second plurality of lines to the beginning of an adjacent line of said second plurality of lines being equal to P and the width of said lines of said first plurality of lines and the width of said lines of said second plurality of lines being equal to W; a plurality of squares of material having said first conductivity wherein each square of said plurality of squares is disposed within an associated square space of said plurality of square spaces and the distance between each edge of each square of said plurality of squares and the adjacent line of said first plurality of lines or the adjacent line of said second plurality of lines is g; such that P is equal to 0.24 inches, g is equal to 0.022 inches, D is equal to 0.228 inches and W is equal to 0.012 inches and a surface of material having a second conductivity, said square grid and said plurality of squares being disposed on at least a portion of said surface.
Claim 2
Dependent Claim 263 words
An improved frequency selective surface comprising: a square grid composed of a first plurality of lines of material having a first conductivity perpendicularly intersecting a second plurality of lines of material having said first conductivity so as to provide a plurality of square spaces therebetween, each of said plurality of lines having a spacing D, the distance from the beginning of a line of said first plurality of lines to the beginning of an adjacent line of said first plurality of lines and the distance from the beginning of a line of said second plurality of lines to the beginning of an adjacent line of said second plurality of lines being equal to P and the width of said lines of said first plurality of lines and the width of said lines of said second plurality of lines being equal to W; a plurality of squares of material having said first conductivity wherein each square of said plurality of squares is disposed within an associated square space of said plurality of square spaces and the distance between each edge of each square of said plurality of squares and the adjacent line of said first plurality of lines or the adjacent line of said second plurality of lines is g; such that P is equal to 0.24 inches, g is equal to 0.022 inches, D is equal to 0.228 inches and W is equal to 0.012 inches and a surface of material having a second conductivity, said square grid and said plurality of squares being disposed on at least a portion of said surface.
Claim 3
Dependent Claim 304 words
A mesh-patch array comprising: a square grid composed of a first plurality of lines of material having a first conductivity perpendicularly intersecting a second plurality of lines of material having said first conductivity so as to provide a plurality of square spaces therebetween, each of said plurality of lines having a spacing D, the distance from the beginning of a line of said first plurality of lines to the beginning of an adjacent line of said first plurality of lines and the distance from the beginning of a line of said second plurality of lines to the beginning of an adjacent line of said second plurality of lines being equal to P and the width of said lines of said first plurality of lines and the width of said lines of said second plurality of lines being equal to W; a plurality of squares of material having said first conductivity wherein each square of said plurality of squares is disposed within an associated square space of said plurality of square spaces and the distance between each edge of each square of said plurality of squares and the adjacent line of said first plurality of lines or the adjacent line of said second plurality lines is g, the dimensions for the elements of the mesh-patch array being related as follows R=1/(1+Y 2 ) and T=1-R, where T represents the equation of said microwave signal of said first frequency that will pass through said surface and R represents the equation of said microwave signal of said second frequency that will be reflected from said surface, Y=1/(2(X-1/B)), X=ωL, B=ωC, ω=2πf, f is the frequency of the applied microwave signal, L is the equivalent inductance of the array, C is the equivalent capacitance of the array, X=D/P(P/λ(ln(csc(πg/P)))), B=4D/P(P/λ(ln(csc(πW/2P)))), and λ is the wavelength of the applied microwave signal.
Claim 4
Dependent Claim 304 words
A mesh-patch array comprising: a square grid composed of a first plurality of lines of material having a first conductivity perpendicularly intersecting a second plurality of lines of material having said first conductivity so as to provide a plurality of square spaces therebetween, each of said plurality of lines having a spacing D, the distance from the beginning of a line of said first plurality of lines to the beginning of an adjacent line of said first plurality of lines and the distance from the beginning of a line of said second plurality of lines to the beginning of an adjacent line of said second plurality of lines being equal to P and the width of said lines of said first plurality of lines and the width of said lines of said second plurality of lines being equal to W; a plurality of squares of material having said first conductivity wherein each square of said plurality of squares is disposed within an associated square space of said plurality of square spaces and the distance between each edge of each square of said plurality of squares and the adjacent line of said first plurality of lines or the adjacent line of said second plurality lines is g, the dimensions for the elements of the mesh-patch array being related as follows R=1/(1+Y 2 ) and T=1-R, where T represents the equation of said microwave signal of said first frequency that will pass through said surface and R represents the equation of said microwave signal of said second frequency that will be reflected from said surface, Y=1/(2(X-1/B)), X=ωL, B=ωC, ω=2πf, f is the frequency of the applied microwave signal, L is the equivalent inductance of the array, C is the equivalent capacitance of the array, X=D/P(P/λ(ln(csc(πg/P)))), B=4D/P(P/λ(ln(csc(πW/2P)))), and λ is the wavelength of the applied microwave signal.

References Cited (Backward Citations)

US3148370A Cited
US3864690A Cited
US4656487A Cited
US4785310A Cited
US4814785A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1998-01-23 1998-07-25 1999-01-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2002-01-23 2002-07-25 2003-01-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2006-01-23 2006-07-25 2007-01-24 $7700.00 Window Closed / Lapsed

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