# US 12,183,968 B1 · Radio frequency signals detection systems > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,183,968 B1 - Document ID: US12183968B1 - Status: Granted - Kind: B1 - Application number: 18/602,911 - Filed: 2024-03-12 - Granted: 2024-12-31 - Earliest claimed: 2022-01-25 - Assignees: The United States of America as represented by the Secretary of the Navy - Applicants: The United States of America, as represented by the Secretary of the Navy - Inventors: Zachary A Sechrist; Christopher G. Yelton; Mark B. Moran; Linda F. Johnson; Joseph E. Estevez; Gretchen H. Hefley - Web page: https://patentgrep.com/patent/US12183968B1 ## CPC - G01R 29/0878: {Sensors; antennas; probes; detectors (wave guide measuring sections G01R1/24)} - 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)} - G01R 29/08: Measuring electromagnetic field characteristics - H01Q 13/02: Waveguide horns - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) - H01Q: ANTENNAS, i.e. RADIO AERIALS (radiators or antennas for microwave heating H05B6/72) ## Abstract The embodiments are directed to systems having an array in intimate adjacent contact with a substrate foundation. The array has a plurality of radio frequency (RF) witness films overlain on the substrate foundation. Each RF witness film is a unit cell defined in a three-dimensional coordinate frame of reference, and is centered at an origin of the three-dimensional coordinate frame of reference. Each RF witness film in the plurality of RF witness films is equally-spaced from adjacent RF witness films. ## Claims ### Claim 1 A system, comprising: an array in intimate adjacent contact with a substrate foundation, said array having a plurality of radio frequency (RF) witness films overlain on said substrate foundation, each RF witness film in said plurality of RF witness films, comprising: a unit cell defined in a three-dimensional coordinate frame of reference defined by an x-axis, a y-axis, and a z-axis, said unit cell centered at an origin of said three-dimensional coordinate frame of reference, said unit cell, comprising: a first conductive layer in intimate adjacent contact with said substrate foundation; a dielectric layer having a first portion and a second portion, said first portion in intimate adjacent contact with said substrate foundation, said second portion in intimate adjacent contact with said first conductive layer; and a second conductive layer having a first side and a second side, said first side of said second conductive layer in intimate adjacent contact with said first portion of said dielectric layer; wherein said first portion transitions to said second portion at a transition zone, wherein said dielectric layer having a sigmoidal shape at said transition zone; wherein said second conductive layer having at least two microstrip extensions perpendicular to each other in the x-y plane; wherein each RF witness film in said plurality of RF witness films is equally-spaced from adjacent RF witness films; wherein each RF witness film in said plurality of RF witness films is configured to receive a direct current (DC) offset voltage. ### Claim 2 (depends on 1) The system according to claim 1, wherein said DC offset voltage is applied to each RF witness film in said plurality of RF witness films between said first conductive layer and said second conductive layer. ### Claim 3 (depends on 1) The system according to claim 1, further comprising: wherein said first conductive layer having first, second, third, and fourth strip segments joined end-to-end and forming three-quarters of a square strip outline in the x-y plane, wherein each of said first, second, third, and fourth strip segments having a first side and a second side, each of said first side of said first, second, third, and fourth strip segments in intimate adjacent contact with said substrate foundation; wherein said first portion is defined by an area interior to said first, second, third, and fourth strip segments in the x-y plane, and between said substrate foundation and said first side of said second conductive layer parallel to said z-axis; wherein said second portion of said dielectric layer is defined by an area delineated by, and in intimate adjacent contact with, each of said second sides of said first, second, third, and fourth strip segments in the x-y plane, and spanning parallel to said z-axis to the z-axis elevation of said first side of said second conductive layer. ### Claim 4 (depends on 3) The system according to claim 3, further comprising: wherein each of said first, second, third, and fourth strip segments having a proximal end and a distal end, said distal end of said first strip segment is adjacent to said proximal end of said second strip segment, said distal end of said second strip segment is adjacent to said proximal end of said third strip segment, said distal end of said third strip segment is adjacent to said proximal end of said fourth strip segment; wherein said first and fourth strip segments are not adjacent to each other; wherein said second conductive layer and said at least two microstrip extensions forming one-quarter of a square strip in the x-y plane, wherein said three-quarters of a square strip outline and said one-quarter of a square strip forming a complete square strip outline in the x-y plane. ### Claim 5 (depends on 4) The system according to claim 4, further comprising: said first microstrip extension having a proximal end at said second conductive layer, and a distal end extending outwardly away from said second conductive layer parallel to said x-axis and said first strip segment; said second microstrip extension having a proximal end at said second conductive layer, and a distal end extending outwardly away from said second conductive layer parallel to said y-axis and said fourth strip segment; a first overlap region defined by the length, parallel to said x-axis, of said first microstrip extension between said proximal end of said first strip segment and said distal end of said first microstrip extension, and parallel to said z-axis from said first microstrip extension through said dielectric layer and through said first conductive layer, and terminating at said first side of said first strip segment of said first conductive layer; and a second overlap region defined by the length, parallel to said y-axis, of said second microstrip extension between said distal end of said fourth strip segment and said distal end of said second microstrip extension, and parallel to said z-axis from said second microstrip extension through said dielectric layer and through said first conductive layer, and terminating at said first side of said fourth strip segment of said first conductive layer. ### Claim 6 (depends on 1) The system according to claim 1, wherein each RF witness film in said plurality of RF witness films is a capacitive structure. ### Claim 7 (depends on 1) The system according to claim 1, wherein said array is a 3×3 array of RF witness films with an array period of 25 millimeters. ### Claim 8 A radio frequency signals detection system, comprising: an array in intimate adjacent contact with a substrate foundation, said array having a plurality of radio frequency (RF) witness films overlain on said substrate foundation; wherein each RF witness film in said plurality of RF witness films is a unit cell defined in a three-dimensional coordinate frame of reference defined by an x-axis, a y-axis, and a z-axis, said unit cell centered at an origin of said three-dimensional coordinate frame of reference, said unit cell, comprising: a first conductive layer in intimate adjacent contact with said substrate foundation; a dielectric layer having a first portion and a second portion, said first portion in intimate adjacent contact with said substrate foundation, said second portion in intimate adjacent contact with said first conductive layer; and a second conductive layer having a first side and a second side, said first side of said second conductive layer in intimate adjacent contact with said first portion of said dielectric layer; wherein said first portion transitions to said second portion at a transition zone, wherein said dielectric layer having a sigmoidal shape at said transition zone; wherein said second conductive layer having at least two microstrip extensions perpendicular to each other in the x-y plane; wherein each RF witness film in said plurality of RF witness films is equally-spaced from adjacent RF witness films; wherein each RF witness film in said plurality of RF witness films is electrically-connected to a direct current (DC) offset voltage; and a horn antenna configured to radiate RF signals at said array. ### Claim 9 (depends on 8) The system according to claim 8, wherein said DC offset voltage is electrically-connected to each RF witness film in said plurality of RF witness films between said first conductive layer and said second conductive layer, said DC offset voltage providing a constant DC voltage to each RF witness film in said plurality of RF witness films. ### Claim 10 (depends on 8) The system according to claim 8, further comprising: wherein said first conductive layer having first, second, third, and fourth strip segments joined end-to-end and forming three-quarters of a square strip outline in the x-y plane, wherein each of said first, second, third, and fourth strip segments having a first side and a second side, each of said first side of said first, second, third, and fourth strip segments in intimate adjacent contact with said substrate foundation; wherein said first portion is defined by an area interior to said first, second, third, and fourth strip segments in the x-y plane, and between said substrate foundation and said first side of said second conductive layer parallel to said z-axis; wherein said second portion of said dielectric layer is defined by an area delineated by, and in intimate adjacent contact with, each of said second sides of said first, second, third, and fourth strip segments in the x-y plane, and spanning parallel to said z-axis to the z-axis elevation of said first side of said second conductive layer. ### Claim 11 (depends on 10) The system according to claim 10, further comprising: wherein each of said first, second, third, and fourth strip segments having a proximal end and a distal end, said distal end of said first strip segment is adjacent to said proximal end of said second strip segment, said distal end of said second strip segment is adjacent to said proximal end of said third strip segment, said distal end of said third strip segment is adjacent to said proximal end of said fourth strip segment; wherein said first and fourth strip segments are not adjacent to each other; wherein said second conductive layer and said at least two microstrip extensions forming one-quarter of a square strip in the x-y plane, said three-quarters of a square strip outline and said one-quarter of a square strip forming a complete square strip outline in the x-y plane. ### Claim 12 (depends on 11) The system according to claim 11, further comprising: said first microstrip extension having a proximal end at said second conductive layer, and a distal end extending outwardly away from said second conductive layer parallel to said x-axis and said first strip segment; said second microstrip extension having a proximal end at said second conductive layer, and a distal end extending outwardly away from said second conductive layer parallel to said y-axis and said fourth strip segment; a first overlap region defined by the length, parallel to said x-axis, of said first microstrip extension between said proximal end of said first strip segment and said distal end of said first microstrip extension, and parallel to said z-axis from said first microstrip extension through said dielectric layer and through said first conductive layer, and terminating at said first side of said first strip segment of said first conductive layer; and a second overlap region defined by the length, parallel to said y-axis, of said second microstrip extension between said distal end of said fourth strip segment and said distal end of said second microstrip extension, and parallel to said z-axis from said second microstrip extension through said dielectric layer and through said first conductive layer, and terminating at said first side of said fourth strip segment of said first conductive layer. ### Claim 13 (depends on 8) The system according to claim 8, wherein each RF witness film in said plurality of RF witness films is a capacitive structure. ### Claim 14 (depends on 8) The system according to claim 8, wherein said array is a 3×3 array of RF witness films with an array period of 25 millimeters. ### Claim 15 (depends on 8) The system according to claim 8, wherein each RF witness film in said plurality of RF witness films is equally-spaced from adjacent RF witness films. ### Claim 16 (depends on 8) The system according to claim 8, wherein said horn antenna is configured to radiate said RF signals in a range of 100 volts per meter to 450 volts per meter at said array.