# US 8,570,238 B2 · Leaky-wave antenna > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,570,238 B2 - Document ID: US8570238B2 - Status: Granted - Kind: B2 - Application number: 13/074,101 - Filed: 2011-03-29 - Published: 2011-10-06 - Granted: 2013-10-29 - Earliest claimed: 2010-03-30 - Assignees: Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V.; Technische Universitaet Ilmenau - Applicants: Rainer Wansch; Mario Schuehler; Matthias Hein - Inventors: Rainer Wansch; Mario Schuehler; Matthias Hein - Web page: https://patentgrep.com/patent/US8570238B2 ## CPC - H01Q 13/20: Non-resonant leaky-waveguide or transmission-line antennas; Equivalent structures causing radiation along the transmission path of a guided wave - H01Q 1/27: Adaptation for use in or on movable bodies (H01Q1/08, H01Q1/12, H01Q1/18 take precedence) - H01Q 1/38: formed by a conductive layer on an insulating support {(patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142)} - H01Q 13/28: comprising elements constituting electric discontinuities and spaced in direction of wave propagation, e.g. dielectric elements or conductive elements forming artificial dielectric - H01Q: ANTENNAS, i.e. RADIO AERIALS (radiators or antennas for microwave heating H05B6/72) ## Abstract A leaky-wave antenna includes a sheet arrangement having first, second and third metalized sheets that are arranged on top of and in parallel with one another and are separated by two di-electric layers, the first metalized sheet having a first two-dimensionally periodic metalization structure, the second metalized sheet having a second two-dimensionally periodic metalization structure, and the third metalized sheet having a continuous metalization area, and an excitation structure above the first metalized sheet for exciting a leaky-wave mode in the sheet arrangement at a working frequency f0 of the leaky-wave antenna, wherein the sheet arrangement exhibits a shape of a regular n-gon with N≧8 (N ∈ Z) or a circular shape as the edge boundary. ## Claims ### Claim 1 A leaky-wave antenna comprising: a sheet arrangement comprising first, second and third metalized sheets that are arranged on top of and in parallel with one another and are separated from one another by two di-electric layers; the first metalized sheet comprising a first two-dimensionally periodic metalization structure, the second metalized sheet comprising a second two-dimensionally periodic metalization structure, and the third metalized sheet comprising a continuous metalization area; and an excitation structure above the first metalized sheet for exciting a leaky-wave mode in the sheet arrangement at a working frequency f0 of the leaky-wave antenna; wherein the sheet arrangement exhibits a shape of a regular n-gon with N≧8 (N ∈ Z) or a circular shape as the edge boundary. ### Claim 2 (depends on 1) The leaky-wave antenna as claimed in claim 1, wherein the sheet arrangement comprises an overall diameter D—with regard to a distance of two opposite sides of the n-gon or of the circle diameter of the sheet arrangement—of less than 5 times the value of the free-space wavelength λo of the leaky-wave antenna at the working frequency f0. ### Claim 3 (depends on 1) The leaky-wave antenna as claimed in claim 1, wherein the first metalization structure comprises a multitude of individual metalization elements, said individual metalization elements comprising a lateral dimension smaller than or equal to 1/10 of the free-space wavelength λo of the leaky-wave antenna at the operating frequency f0. ### Claim 4 (depends on 1) The leaky-wave antenna as claimed in claim 1, wherein the second metalization structure comprises a multitude of further individual metalization elements, said further individual metalization elements comprising a lateral dimension that is smaller than or equal to 1/10 of the free-space wavelength λo of the leaky-wave antenna at the working frequency f0. ### Claim 5 (depends on 3) The leaky-wave antenna as claimed in claim 3, wherein the sheet arrangement comprises a lateral extension D that comprises less than 50 individual metalization elements of the first metalized sheet along a distance of two opposite sides of the n-gon or of the circle diameter of the sheet arrangement. ### Claim 6 (depends on 1) The leaky-wave antenna as claimed in claim 1, wherein the sheet arrangement is configured as a periodically structured multi-sheet printed circuit board. ### Claim 7 (depends on 1) The leaky-wave antenna as claimed in claim 1, wherein the sheet arrangement comprises a multitude of adjacent unit cells, a unit cell representing an area which corresponds to a projection through the sheet arrangement with regard to the floor space of a single individual metalization element of the first metalized sheet. ### Claim 8 (depends on 7) The leaky-wave antenna as claimed in claim 7, wherein the plurality of further individual metalization elements of the second metalized sheet is rotated by an angle of 45° with regard to the individual metalization elements of the first metalized sheet. ### Claim 9 (depends on 7) The leaky-wave antenna as claimed in claim 7, wherein the area centers of the individual metalization elements of the first metalized sheet are offset from the further individual metalization elements of the second metalized sheet. ### Claim 10 (depends on 1) The leaky-wave antenna as claimed in claim 1, wherein the sheet arrangement comprises a non-directional dispersion characteristic at the working frequency f0. ### Claim 11 (depends on 1) The leaky-wave antenna as claimed in claim 1, wherein the sheet arrangement is configured to provide a radially symmetrical propagation of leaky waves at the operating frequency of the leaky-wave antenna upon excitation by the excitation structure. ### Claim 12 (depends on 1) The leaky-wave antenna as claimed in claim 1, wherein the excitation structure is configured to excite a linearly, cross-, and/or circularly polarized wave in the sheet arrangement. ### Claim 13 (depends on 12) The leaky-wave antenna as claimed in claim 12, wherein the excitation structure is centrally arranged on the sheet arrangement as a cross-dipole arrangement.