Layer frequency selective surface assembly and method of modulating the power or frequency characteristics thereof

• US 5,287,118 A
• Filed: 06/11/1991
• Issued: 02/15/1994
• Est. Priority Date: 07/24/1990
• Status: Expired due to Term

• Current Assignee: SELEX Sensors and Airborne Systems Ltd. (Leonardo S.p.A.)
• Original Assignee: British Aerospace, Inc. (BAE Systems Plc)
• Inventors: Budd, Christopher
• Primary Examiner(s): Lee, Benny T.
• Application Number:
  US07/713,263
• Time in Patent Office: 980 Days
• Field of Search: 343/909, 343/910, 343/911 R, 343/753, 343/754, 343/755, 342/5, 342/6, 342/11
• US Class Current: 343/909
• CPC Class Codes: G02B 26/007 the movable or deformable optical element controlling the colour, i.e. a spectral characteristic, of the light
• CPC Class Codes: G02B 5/204 in which spectral selection is performed by means of a conductive grid or array, e.g. frequency selective surfaces for use with wavelengths longer than the infrared light H01Q15/0006
• CPC Class Codes: H01Q 15/0013 said selective devices working as frequency-selective reflecting surfaces, e.g. FSS, dichroic plates, surfaces being partly transmissive and reflective
• CPC Class Codes: H01Q 3/44 varying the electric or magnetic characteristics of reflecting, refracting, or diffracting devices associated with the radiating element

Abstract

The power or frequency characteristics of a layered frequency selective surface assembly (1) having a dielectric substrate layer (2) and, superimposed therewith at a spacing (X) therefrom, at least one layer (3) of electrically conductive elements (4) disposed in an array, is modulated by moving at least one layer (2, 3) relative to the or each other layer (2, 3). The layers (2, 3) maybe substantially planar or substantially non-planar and may be disposed substantially parallel to one another. Relative movement between the layers (2, 3) may retain the substantially parallel orientation or may not retain the substantially parallel orientation. The relative movement may have the effect of changing the spacing between the layers (2, 3) for example to tilt, skew or rotate one layer relative to the or each other layer.

Claims

1. A layered frequency selective surface assembly device comprising:

a dielectric substrate layer;

at least one conductive layer of electrically conductive elements arranged in array configuration, said at least one conductive layer overlapping and spaced apart from said dielectric substrate layer; and

layer positioning means, coupled to one of either said dielectric substrate layer and said at least one conductive layer, for selectively varying the distance between the dielectric substrate layer and said at least one conductive layer so as to tune the layered frequency selective surface assembly device to a position where externally provided signals are either reflected or accepted in accordance with each signal'"'"'s characteristics.

2. The device of claim 1, wherein said dielectric substrate layer and said at least one conductive layer are initially disposed in parallel to accept an initial signal response having predetermined signal characteristics, and are variably positioned in non-parallel fashion to accept a signal response different from said initial signal response.

3. The device of claim 2, wherein said layer positioning means selectively varies the position between the dielectric substrate layer and said at least one conductive layer, initially disposed in parallel, by pivoting the respective layer coupled thereto along an axis which is normal to the initial parallel direction of said dielectric substrate layer and the at least one conductive layer.

4. The device of claim 2, wherein said externally provided signals are accepted or reflected on the basis of the frequency characteristics of each signal.

5. The device of claim 2, wherein said externally provided signals are accepted or reflected on the basis of the power characteristics of each signal.

6. The device of claim 1, wherein said externally provided signals are accepted or reflected on the basis of the frequency characteristics of each signal.

7. The device of claim 1, wherein said externally provided signals are accepted or reflected on the basis of the power characteristics of each signal.

8. The device of claim 1, wherein said dielectric substrate layer and said at least one conductive layer are both non-planar shaped.

9. The device of claim 1, wherein said dielectric substrate layer and said at least one conductive layer are both substantially planar shaped.

10. The device of claim 1, wherein said layer positioning means selectively varies the position between the dielectric substrate layer and said at least one conductive layer by variably changing a parallel distance therebetween.

11. The device of claim 1, wherein said dielectric substrate layer and said at least one conductive layer are initially disposed in parallel to accept an initial signal response having predetermined signal characteristics, and are variably positioned to a different parallel position to accept a signal response different from said initial signal response.

12. The device of claim 11, wherein said layer positioning means selectively varies the position between the dielectric substrate layer and said at least one conductive layer, initially disposed in parallel, by pivoting the respective layer coupled thereto along an axis which is normal to the initial parallel direction of said dielectric substrate layer and the at least one conductive layer.