# US 11,994,549 B1 · Method and system to determine radio frequency antenna electromagnetic field spatial distribution > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,994,549 B1 - Document ID: US11994549B1 - Status: Granted - Kind: B1 - Application number: 18/401,526 - Filed: 2023-12-31 - Granted: 2024-05-28 - Earliest claimed: 2023-12-31 - Applicants: ENDRA Life Sciences Inc. - Inventors: Idan Steinberg; Michael M. Thornton; Christopher Nelson Davis; Jang Hwan Cho - Web page: https://patentgrep.com/patent/US11994549B1 ## CPC - G01R 29/10: Radiation diagrams of antennas - G01R 29/0821: {rooms and test sites therefor, e.g. anechoic chambers, open field sites or TEM cells (for testing antennas G01R29/105)} - G01R 29/0878: {Sensors; antennas; probes; detectors (wave guide measuring sections G01R1/24)} - G01R 29/0892: {Details related to signal analysis or treatment; presenting results, e.g. displays; measuring specific signal features other than field strength, e.g. polarisation, field modes, phase, envelope, maximum value} - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) ## Abstract A method for determining an electromagnetic field spatial distribution of a radio frequency (RF) antenna which includes the steps of emitting with the RF antenna, a plurality of RF energy pulses into a homogeneous medium; performing a plurality of thermoacoustic signal measurements of the plurality of RF energy pulses, wherein each of the thermoacoustic signal measurements is performed in a similar manner; utilizing a variance in the plurality of thermoacoustic signal measurements to generate a reconstructed pressure distribution for a volume located within the homogeneous medium; and calculating the RF antenna electromagnetic field spatial distribution within the volume based upon the reconstructed pressure distribution for the volume located within the homogeneous medium. ## Claims ### Claim 1 A method for determining an electromagnetic field spatial distribution of a radio frequency (RF) antenna, the method comprising: (i) emitting, by the RF antenna, a plurality of RF energy pulses into a homogeneous medium; (ii) performing, by at least one processor, a plurality of thermoacoustic signal measurements of the plurality of RF energy pulses, wherein each of the thermoacoustic signal measurements is performed in a similar manner; (iii) generating, by the at least one processor, a reconstructed pressure distribution for a volume located within the homogeneous medium using a variance in the plurality of thermoacoustic signal measurements; and (iv) generating, by the at least one processor, a representation of the RF antenna electromagnetic field spatial distribution within the volume based upon a calculation using the reconstructed pressure distribution for the volume located within the homogeneous medium. ### Claim 2 (depends on 1) The method of claim 1, wherein the plurality of thermoacoustic signal measurements is performed with a thermoacoustic system comprising the RF antenna and one or more thermoacoustic transducers. ### Claim 3 (depends on 1) The method of claim 1, wherein the representation is a two dimensional or three dimensional visual representation of the RF antenna electromagnetic field spatial distribution. ### Claim 4 (depends on 1) The method of claim 1, wherein the homogeneous medium is a liquid. ### Claim 5 (depends on 4) The method of claim 4, wherein the liquid is water. ### Claim 6 (depends on 1) The method of claim 1, wherein the homogenous medium has a relative permittivity between 10 and 70. ### Claim 7 (depends on 1) The method of claim 1, wherein the homogeneous medium is a solid. ### Claim 8 A system for determining an electromagnetic field spatial distribution of a radio frequency (RF) antenna, the system comprising: an RF antenna configured to emit a plurality of RF energy pulses into a homogeneous medium; at least one processor configured to: perform a plurality of thermoacoustic signal measurements of the plurality of RF energy pulses, wherein each of the thermoacoustic signal measurements is performed in a similar manner; generate a reconstructed pressure distribution for a volume located within the homogeneous medium using a variance in the plurality of thermoacoustic signal measurements; and generate a representation of the RF antenna electromagnetic field spatial distribution within the volume based upon a calculation using the reconstructed pressure distribution for the volume located within the homogeneous medium. ### Claim 9 (depends on 8) The system of claim 8, further comprising one or more thermoacoustic transducers. ### Claim 10 (depends on 8) The system of claim 8, wherein the representation is a two dimensional or three dimensional visual representation of the RF antenna electromagnetic field spatial distribution. ### Claim 11 (depends on 8) The system of claim 8, wherein the homogeneous medium is a liquid. ### Claim 12 (depends on 11) The system of claim 11, wherein the liquid is water. ### Claim 13 (depends on 8) The system of claim 8, wherein the homogenous medium has a relative permittivity between 10 and 70. ### Claim 14 (depends on 8) The system of claim 8, wherein the homogeneous medium is a solid. ### Claim 15 A non-transitory machine-readable storage medium having computer-executable instructions stored thereon that, when executed by one or more processors, cause the one or more processors to perform operations comprising: performing, by at least one processor, a plurality of thermoacoustic signal measurements of a plurality of RF energy pulses emitted by an RF antenna, wherein each of the thermoacoustic signal measurements is performed in a similar manner; generating, by the at least one processor, a reconstructed pressure distribution for a volume located within a homogeneous medium using a variance in the plurality of thermoacoustic signal measurements; and generating, by the at least one processor, a representation of a RF antenna electromagnetic field spatial distribution within the volume based upon a calculation using the reconstructed pressure distribution for the volume located within the homogeneous medium. ### Claim 16 (depends on 15) The non-transitory machine-readable storage medium of claim 15, wherein the plurality of thermoacoustic signal measurements is performed with a thermoacoustic system comprising the non-transitory machine-readable storage medium, the RF antenna, and one or more thermoacoustic transducers. ### Claim 17 (depends on 15) The non-transitory machine-readable storage medium of claim 15, wherein the representation is a two dimensional or three dimensional visual representation of the RF antenna electromagnetic field spatial distribution. ### Claim 18 (depends on 15) The non-transitory machine-readable storage medium of claim 15, wherein the homogeneous medium is a liquid. ### Claim 19 (depends on 15) The non-transitory machine-readable storage medium of claim 15, wherein the homogenous medium has a relative permittivity between 10 and 70. ### Claim 20 (depends on 15) The non-transitory machine-readable storage medium of claim 15, wherein the homogeneous medium is a solid.