# US 10,122,078 B2 · Surface wave antenna using graded dielectric material > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,122,078 B2 - Document ID: US10122078B2 - Status: Granted - Kind: B2 - Application number: 15/143,395 - Filed: 2016-04-29 - Published: 2018-07-26 - Granted: 2018-11-06 - Earliest claimed: 2015-07-17 - Assignees: L-3 Communications Corporation - Applicants: L-3 Communications Corporation - Inventors: George Zohn Hutcheson; Maurio Batista Grando - Web page: https://patentgrep.com/patent/US10122078B2 ## CPC - H01Q 1/422: {comprising two or more layers of dielectric material (H01Q1/425 takes precedence)} - H01Q 1/286: {substantially flush mounted with the skin of the craft} - H01Q 1/42: Housings not intimately mechanically associated with radiating elements, e.g. radome - H01Q 9/0428: {radiating a circular polarised wave} - H01Q 9/0464: {Annular ring patch} - H01Q 9/0492: {circularly polarised} - H01Q 9/30: with feed to end of elongated active element, e.g. unipole (H01Q9/44 takes precedence) - H01Q 13/26: Surface waveguide constituted by a single conductor, e.g. strip conductor - H01Q: ANTENNAS, i.e. RADIO AERIALS (radiators or antennas for microwave heating H05B6/72) ## Abstract A surface wave antenna system is presented. The surface wave antenna system is configured to be coupled to a surface and includes an antenna and a radiation modifier. The radiation modifier includes a material having a graded dielectric constant. A final portion of the radiation modifier includes material having a dielectric constant that produces a signal phase velocity in signals emitted from the radiation modifier that is substantially equal to a phase velocity of signals on the surface. ## Claims ### Claim 1 A surface wave antenna system configured to be coupled to a surface, comprising: an antenna; and a radiation modifier comprising a material having a graded dielectric constant, where the graded dielectric constant of the material reduces signals emitted from or received by the antenna system in directions other than a desired direction of propagation and increases the gain of the antenna system in the desired direction of propagation, wherein a final portion of the radiation modifier comprises material having a dielectric constant that produces a desired phase velocity in signals emitted from or received by the radiation modifier. ### Claim 2 (depends on 1) The surface wave antenna system of claim 1, wherein the radiation modifier is configured as a high temperature radome. ### Claim 3 (depends on 1) The surface wave antenna system of claim 1, wherein the radiation modifier comprises a plurality of layers of materials, each material having a differing dielectric constant. ### Claim 4 (depends on 3) The surface wave antenna system of claim 3, wherein at least some of the plurality of layers comprise silicon nitride, each such layer having a differing porosity. ### Claim 5 (depends on 1) The surface wave antenna system of claim 1, wherein the radiation modifier has a dielectric constant that varies along more than one dimension. ### Claim 6 (depends on 1) The surface wave antenna system of claim 1, wherein the phase velocity of signals emitted by the radiation modifier is less than the speed of light in a medium adjacent to a portion of the radiation modifier from which the signals are emitted. ### Claim 7 A surface wave antenna system configured to be coupled to a surface, comprising: an antenna; and a radiation modifier comprising a material having a graded dielectric constant, wherein a final portion of the radiation modifier comprises material having a dielectric constant that produces a desired phase velocity in signals emitted from the radiation modifier: wherein an initial portion of the radiation modifier comprises material having a dielectric constant that reduces reflections from the surface of the initial portion of signals emitting from the antenna and entering the radiation modifier. ### Claim 8 (depends on 1) The surface wave antenna system of claim 1, wherein the antenna is one of a waveguide with open broad wall, a monopole antenna, a circular patch antenna, and a monopole antenna with top hat. ### Claim 9 (depends on 1) The surface wave antenna system of claim 1, wherein the antenna is a doorstop antenna and the radiation modifier is located between an exit aperture of the antenna and a surface aperture of the surface, the surface wave antenna system comprising a conformal antenna system. ### Claim 10 A radiation modifier configured to be used with an antenna as part of an antenna system and to be coupled to a surface, the radiation modifier comprising a material having a graded dielectric constant, where the graded dielectric constant of the material reduces signals emitted from or received by the antenna system in directions other than a desired direction of propagation and increases the gain of the antenna system in the desired direction of propagation, and wherein a final portion of the radiation modifier comprises material having a dielectric constant that produces a desired phase velocity in signals emitted from the radiation modifier. ### Claim 11 (depends on 10) The radiation modifier of claim 10, wherein the radiation modifier is configured as a high temperature radome for the antenna. ### Claim 12 (depends on 10) The radiation modifier of claim 10, wherein the radiation modifier comprises a plurality of layers of materials, each material having a differing dielectric constant. ### Claim 13 (depends on 12) The radiation modifier of claim 12, wherein at least some of the plurality of layers comprise a porous ceramic material, each such layer having a differing porosity. ### Claim 14 (depends on 10) The radiation modifier of claim 10, wherein the radiation modifier has a dielectric constant that varies along more than one dimension. ### Claim 15 (depends on 10) The radiation modifier of claim 10, wherein the signal phase velocity of signals emitted by the radiation modifier is less than the speed of light in a medium adjacent to a portion of the radiation modifier from which the signals are emitted. ### Claim 16 (depends on 10) The radiation modifier of claim 10, wherein an initial portion of the radiation modifier comprises material having a dielectric constant that is based on the signal phase velocity of signals received from the antenna. ### Claim 17 (depends on 10) The radiation modifier of claim 10, wherein the radiation modifier is configured for use in one of one of a waveguide with open broad wall, a monopole antenna, a circular patch antenna, and a monopole antenna with top hat. ### Claim 18 (depends on 10) The radiation modifier of claim 10, wherein the radiation modifier is configured as a cylinder and the dielectric constant is graded radially from a center line of the cylinder to a perimeter of the cylinder of the radiation modifier. ### Claim 19 (depends on 18) The radiation modifier of claim 18, wherein the radiation modifier comprises a plurality of concentric cylindrical layers of materials, each material having a differing dielectric constant. ### Claim 20 (depends on 18) The radiation modifier of claim 18, wherein the dielectric constant is further graded from one end of the cylinder to the other end of the cylinder. ### Claim 21 (depends on 1) The surface wave antenna system of claim 1, wherein the radiation modifier is located between an exit aperture of the antenna and a surface aperture of the surface; and where the radiation modifier comprises a material having a spatially graded dielectric constant with a tapered profile that varies in at least two dimensions both in a direction from the antenna to the surface and in a different direction to increase propagation of electromagnetic (EM) surface waves in a desired direction of propagation. ### Claim 22 (depends on 1) The surface wave antenna system of claim 1, wherein the radiation modifier is located between an exit aperture of the antenna and a surface aperture of the surface; wherein the surface comprises a skin of a side of a vehicle having a nose oriented to face the direction of travel of the vehicle and the skin facing a different direction than the nose of the vehicle; and where the radiation modifier comprises a material having a spatially graded dielectric constant with a tapered profile that varies in at least two dimensions both in a direction from the antenna to the skin and in a different direction to increase propagation of electromagnetic (EM) surface waves in a direction toward the nose of the vehicle. ### Claim 23 (depends on 1) The surface wave antenna system of claim 1, wherein an exit aperture of the antenna is located adjacent a surface aperture of the surface; wherein the radiation modifier is located external to the surface; wherein the dielectric constant of the radiation modifier varies continuously in a direction normal to the surface to increase propagation of electromagnetic (EM) surface waves in a direction perpendicular to a normal vector of the surface. ### Claim 24 (depends on 23) The surface wave antenna system of claim 23, wherein the surface comprises a skin of a vehicle; wherein the radiation modifier is located external to the vehicle skin and extends as a dielectric waveguide along the skin of the vehicle beyond the surface aperture and in a desired direction of signal propagation to increase the gain of the antenna system in the desired direction of propagation. ### Claim 25 (depends on 24) The surface wave antenna system of claim 24, wherein the vehicle has a nose oriented to face the direction of travel of the vehicle; wherein the radiation modifier extends as a dielectric waveguide along the outside of the skin of the vehicle beyond the surface aperture and in a direction of signal propagation toward the nose of the vehicle to increase the gain of the antenna system in the direction of propagation toward the nose of the vehicle. ### Claim 26 (depends on 25) The surface wave antenna system of claim 25, the radiation modifier comprises porous ceramic material that provide thermal protection to the vehicle skin. ### Claim 27 (depends on 1) The surface wave antenna system of claim 1, wherein a final portion of the radiation modifier comprises material having a dielectric constant that produces a signal phase velocity in signals emitted from or received by the radiation modifier that is equal to a phase velocity of signals on the surface. ### Claim 28 (depends on 1) The surface wave antenna system of claim 1, wherein the radiation modifier comprises a plurality of layers of materials, each material having a differing dielectric constant, and two or more of the layers having a different thickness from each other. ### Claim 29 A method, comprising: emitting or receiving signals of desired phase velocity from a final portion of a radiation modifier of a surface wave antenna system that is coupled to a surface, the final portion of the radiation modifier comprising a material having a dielectric constant producing a desired phase velocity in the emitted or received signals, and the radiation modifier being coupled between an antenna and the surface; and where the radiation modifier comprises a material having a graded dielectric constant that reduces signals emitted from or received by the antenna system in directions other than a desired direction of propagation and increases the gain of the antenna system in the desired direction of propagation. ### Claim 30 (depends on 29) The method of claim 29, wherein the radiation modifier is located between an exit aperture of the antenna and a surface aperture of the surface, the surface comprising a skin of a vehicle having a nose; and where the method further comprises: moving the vehicle in a direction of travel with the vehicle nose oriented to face the direction of travel of the vehicle and the skin facing a different direction than the nose of the vehicle; and where the radiation modifier comprises a material having a spatially graded dielectric constant with a tapered profile that varies in at least two dimensions both in a direction from the antenna to the skin and in a different direction to increase propagation of electromagnetic (EM) surface waves in a direction toward the nose of the vehicle. ### Claim 31 (depends on 30) The method of claim 30, wherein an exit aperture of the antenna is located adjacent a surface aperture of the vehicle skin; wherein the radiation modifier is located external to the vehicle skin; wherein the dielectric constant of the radiation modifier varies continuously in a direction normal to the surface to increase propagation of electromagnetic (EM) surface waves in a direction perpendicular to a normal vector of the skin; and where the radiation modifier is located external to the vehicle skin and extends as a dielectric waveguide along the outside of the skin of the vehicle beyond the surface aperture and in a direction of signal propagation toward the nose of the vehicle to increase the gain of the antenna system in the direction of propagation toward the nose of the vehicle.