# US 12,216,145 B2 · Anechoic chamber for testing a device under test over-the-air, a system, and a method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,216,145 B2 - Document ID: US12216145B2 - Status: Granted - Kind: B2 - Application number: 18/062,731 - Filed: 2022-12-07 - Published: 2023-07-13 - Granted: 2025-02-04 - Earliest claimed: 2022-01-10 - Assignees: Rohde & Schwarz GmbH & Co. KG - Applicants: Rohde & Schwarz GmbH & Co. KG - Inventors: Heinz Mellein - Web page: https://patentgrep.com/patent/US12216145B2 ## CPC - 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 29/105: {using anechoic chambers; Chambers or open field sites used therefor (test sites used for measuring on other objects than aerials G01R29/0828; wave absorbing devices H01Q17/00)} - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) ## Abstract The present disclosure generally relates to an anechoic chamber for testing a device under test over-the-air, a system, and a method. The anechoic chamber includes at least one reflecting surface being configured to variably manipulate in a defined manner at least one reflection process of at least one electromagnetic wave usable for testing the device under test. ## Claims ### Claim 1 An anechoic chamber for testing a device under test over-the-air, the anechoic chamber comprising at least one reflecting surface being coupled to a control circuit and being configured to variably manipulate in a defined manner at least one reflection process of at least one electromagnetic wave usable for testing the device under test, wherein a variable manipulation of the reflection process is caused by at least one property of the at least one reflecting surface being variably controlled in-field by a control signal of the control circuit, and wherein at least a direction of the at least one electromagnetic wave is manipulatable based on the variable manipulation of the reflection process. ### Claim 2 (depends on 1) The anechoic chamber of claim 1, wherein the at least one reflecting surface is configured to variably have a non-negligible reflection coefficient within a partial surface area thereof. ### Claim 3 (depends on 1) The anechoic chamber of claim 1, wherein the at least one reflecting surface is configured to variably have a non-negligible reflection coefficient with regard to a limited reflection angle range. ### Claim 4 (depends on 1) The anechoic chamber according to claim 1, wherein the at least one reflecting surface is configured to variably manipulate at least one refraction process or diffraction process of the at least one electromagnetic wave. ### Claim 5 A system for testing a device under test over-the-air, the system comprising the anechoic chamber and a device under test, wherein the anechoic chamber comprises at least one reflecting surface being coupled to a control circuit and being configured to variably manipulate in a defined manner at least one reflection process of at least one electromagnetic wave usable for testing the device under test, wherein the anechoic chamber comprises a testing area, wherein the system has at least one transmission antenna element and/or at least one reception antenna element, and wherein the device under test and the at least one reflecting surface are arranged within the testing area, and wherein a variable manipulation of the reflection process is caused by at least one property of the at least one reflecting surface being variably controlled in-field by a control signal of the control circuit, and wherein at least a direction of the at least one electromagnetic wave is manipulatable based on the variable manipulation of the reflection process. ### Claim 6 (depends on 5) The system of claim 5, wherein the at least one reflecting surface at least partially comprises a cylindrical shape. ### Claim 7 (depends on 5) The system of claim 5, wherein the anechoic chamber comprises at least one wall portion delimiting the testing area and having the at least one reflecting surface, wherein the at least one reflecting surface is substantially flat. ### Claim 8 (depends on 5) The system according to claim 5, wherein the anechoic chamber comprises at least two transmission antenna elements and at least two reception antenna elements establishing a multiple-input/multiple-output antenna array. ### Claim 9 (depends on 5) The system according to claim 5, wherein the at least one reflecting surface at least partially comprises materials, devices or elements selected from the group consisting of graphene, nonlinear optical materials, non-foster elements, ferrites, YIG, BST, liquid crystals, microfluidics, mechanical elements, MEMS, PIN diodes, and varactors. ### Claim 10 (depends on 5) The system according to claim 5, comprising at least one processing circuit that is coupled to the at least one transmission antenna element and/or the at least one reception antenna element, and wherein the at least one processing circuit is also coupled to the at least one reflecting surface. ### Claim 11 A method of testing a device under test over-the-air, the method comprising: providing an anechoic chamber having a testing area with the device under test and at least one reflecting surface arranged therein and being coupled to a control circuit, the anechoic chamber comprising at least one transmission antenna element and/or at least one reception antenna element, emitting at least one electromagnetic wave, variably manipulating, using the at least one reflecting surface, at least one reflection process of the at least one electromagnetic wave in a defined manner, wherein a variable manipulation of the reflection process is caused by at least one property of the at least one reflecting surface being variably controlled in-field by a control signal of the control circuit, and wherein at least a direction of the at least one electromagnetic wave is manipulatable based on the variable manipulation of the reflection process, and receiving the at least one electromagnetic wave reflected by the at least one reflecting surface. ### Claim 12 (depends on 11) The method of claim 11, wherein the at least one reflecting surface is variably manipulated to have a non-negligible reflection coefficient within a partial surface area thereof. ### Claim 13 (depends on 11) The method of claim 11, wherein the at least one reflecting surface is variably manipulated to have a non-negligible reflection coefficient with regard to a limited reflection angle range. ### Claim 14 (depends on 11) The method according to claim 11 further comprising: variably manipulating, using the at least one reflecting surface, at least one refraction process or diffraction process of the at least one electromagnetic wave. ### Claim 15 (depends on 11) The method according to claim 11, wherein, using at least two transmission antenna elements, multiple electromagnetic waves are emitted, and wherein, using at least two reception antenna elements, multiple electromagnetic waves reflected by the at least one reflecting surface are received to test the device under test based on a multiple-input/multiple-output antenna array.