# US 11,112,487 B2 · Method for performing imaging polarimetry, transponder, and system for performing imaging polarimetry > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,112,487 B2 - Document ID: US11112487B2 - Status: Granted - Kind: B2 - Application number: 15/953,665 - Filed: 2018-04-16 - Published: 2018-08-23 - Granted: 2021-09-07 - Earliest claimed: 2015-10-16 - Assignees: Symeo GmbH - Applicants: Friedrich-Alexander—Universitaet Erlangen-Nuernberg - Inventors: Martin Vossiek; Julian Adametz; Maximilian Poepperl - Web page: https://patentgrep.com/patent/US11112487B2 ## CPC - G01S 7/024: {using polarisation effects (in waveguides H01P1/165; for aerials H01Q, e.g. H01Q15/22, H01Q15/24, H01Q19/195)} - G01S 13/751: {wherein the responder or reflector radiates a coded signal} - G01S 13/89: for mapping or imaging - H01Q 15/248: {using a reflecting surface, e.g. twist reflector (combination with a polarisation filter in dual reflector antennas H01Q19/195)} - H01Q 1/2208: {associated with components used in interrogation type services, i.e. in systems for information exchange between an interrogator/reader and a tag/transponder, e.g. in Radio Frequency Identification [RFID] systems (methods or arrangements for sensing record carriers, e.g. for reading patterns G06K7/00; record carrier for use with machines and with at least a part designed to carry digital markings G06K19/00)} - G01S: RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES - H01Q: ANTENNAS, i.e. RADIO AERIALS (radiators or antennas for microwave heating H05B6/72) ## Abstract A method serves for imaging polarimetry. A chipless, passive transponder which has a plurality of surface regions with different polarimetric properties is illuminated fully polarimetrically by radar radiation. At least one polarization-encoded image of the transponder is generated using the radar radiation reflected thereby, and the different surface regions of the transponder in the polarization-encoded image can be recognized by their at least one polarimetric property. The passive, chipless transponder has at least two surface regions with different polarimetric structures. ## Claims ### Claim 1 A passive, chipless transponder, comprising: at least two surface regions each configured to generate differentiated polarimetric backscatter in response to polarimetric illumination, wherein at least one of said at least two surface regions having a three-dimensional surface form with at least one side wall having an angle of inclination and said three-dimensional surface form defining a roof mirror. ### Claim 2 (depends on 1) The transponder according to claim 1, wherein said at least two surface regions have a same basic form, but different dimensioning and/or alignment. ### Claim 3 (depends on 1) The transponder according to claim 1, wherein the chipless, passive transponder is formed of one material or a composite of materials. ### Claim 4 (depends on 1) The transponder according to claim 1, wherein different ones of said surface regions are assigned materials with different polarimetric backscattering behavior. ### Claim 5 A system, comprising: at least one passive, chipless transponder having at least two surface regions each configured to generate differentiated polarimetric backscatter in response to polarimetric illumination, wherein at least one of said at least two surface regions having a three-dimensional surface form with a plurality of parallel side walls each having an angle of inclination and said three-dimensional surface form defining a roof mirror; and at least one reader for radar-based reading of said at least one passive, chipless transponder, said at least one reader programmed to: irradiate said chipless, passive transponder by means of radar radiation with at least two differently polarized waves including a first polarized wave and a second polarized wave; generate a first polarization-encoded image of said chipless, passive transponder on a basis of the radar radiation reflected from said chipless, passive transponder based on the first polarized wave, the radar radiation being reflected without an energizing current operating an integrated circuit on said transponder nor by use of an antenna on said transponder; and generate a second polarization-encoded image of said chipless, passive transponder on a basis of the radar radiation reflected from said chipless, passive transponder based on the second polarized wave, the radar radiation being reflected without an energizing current operating an integrated circuit on said transponder nor by use of an antenna on said transponder; decode an identifier of said passive, chipless transponder using the first and second polarization encoded images. ### Claim 6 (depends on 1) The transponder according to claim 1, wherein said at least two surface regions are aligned parallel to a horizontal line. ### Claim 7 (depends on 5) The system according to claim 5, wherein said at least two surface regions of said at least one transponder are aligned parallel to a horizontal line. ### Claim 8 A passive, chipless and antennaless transponder, comprising: at least two surface regions each configured to generate differentiated polarimetric backscatter in response to polarimetric illumination, wherein at least one of said at least two surface regions having a three-dimensional surface form with at least one side wall having a predetermined angle of inclination, the transponder responding to an interrogation from a reader without being provided an energizing current for operating an integrated circuit. ### Claim 9 (depends on 8) The transponder according to claim 8, wherein at least one of said at least two surface regions forms a roof mirror. ### Claim 10 (depends on 8) The transponder according to claim 8, wherein said at least two surface regions each form a roof mirror having parallel longitudinal grooves formed therein, but different angles of inclination. ### Claim 11 (depends on 8) The transponder according to claim 8, wherein said at least two surface regions do not form an antenna. ### Claim 12 (depends on 8) The transponder according to claim 8, further comprising a plate-shaped aluminum part having a surface containing said at least two surface regions.