Abstract: Disclosed herein are systems using acoustic metamaterial surfaces comprising arrangements of unit cells arranged to introduce time delays to an incident acoustic wave. In embodiments the relative positions of two or more acoustic metasurfaces (81, 82) is selected or adjusted to control the acoustic output of the system such that the acoustic output of the system is a non-linear combination of the respective operations performed by the plurality of acoustic metasurfaces (81, 82), the non-linear combination being a convolution of the respective operations performed by the plurality of acoustic metasurfaces that is determined as a function of the relative positioning between the acoustic metasurfaces (81, 82). Also disclosed are applications of such acoustic metasurfaces in noise-reducing structures.

Abstract: A device for manipulating an incident acoustic wave to generate an acoustic output is described wherein the device comprises a plurality of unit cells arranged into an array, at least some of said unit cells being configured to introduce time delays to an incident acoustic wave at the respective positions of the unit cells within the array of unit cells, such that said plurality of unit cells define an array of time delays to thereby define a spatial delay distribution for manipulating an incident acoustic wave to generate an acoustic output. The array of time delays may be re-configured to vary the spatial delay distribution of the device in order to generate different acoustic outputs. Also described are methods for designing or configuring such devices.

Abstract: A device for manipulating an incident acoustic wave to generate an acoustic output is described wherein the device comprises a plurality of unit cells arranged into an array, at least some of said unit cells being configured to introduce time delays to an incident acoustic wave at the respective positions of the unit cells within the array of unit cells, such that said plurality of unit cells define an array of time delays to thereby define a spatial delay distribution for manipulating an incident acoustic wave to generate an acoustic output. The array of time delays may be re-configured to vary the spatial delay distribution of the device in order to generate different acoustic outputs. Also described are methods for designing or configuring such devices.

Abstract: A device for manipulating an incident acoustic wave to generate an acoustic output is described wherein the device comprises a plurality of unit cells arranged into an array, at least some of said unit cells being configured to introduce time delays to an incident acoustic wave at the respective positions of the unit cells within the array of unit cells, such that said plurality of unit cells define an array of time delays to thereby define a spatial delay distribution for manipulating an incident acoustic wave to generate an acoustic output. The array of time delays may be re-configured to vary the spatial delay distribution of the device in order to generate different acoustic outputs. Also described are methods for designing or configuring such devices.

Abstract: Disclosed herein are systems using acoustic metamaterial surfaces comprising arrangements of unit cells arranged to introduce time delays to an incident acoustic wave. In embodiments the relative positions of two or more acoustic metasurfaces (81, 82) is selected or adjusted to control the acoustic output of the system such that the acoustic output of the system is a non-linear combination of the respective operations performed by the plurality of acoustic metasurfaces (81, 82), the non-linear combination being a convolution of the respective operations performed by the plurality of acoustic metasurfaces that is determined as a function of the relative positioning between the acoustic metasurfaces (81, 82). Also disclosed are applications of such acoustic metasurfaces in noise-reducing structures.

Abstract: A device for manipulating an incident acoustic wave to generate an acoustic output is described wherein the device comprises a plurality of unit cells arranged into an array, at least some of said unit cells being configured to introduce time delays to an incident acoustic wave at the respective positions of the unit cells within the array of unit cells, such that said plurality of unit cells define an array of time delays to thereby define a spatial delay distribution for manipulating an incident acoustic wave to generate an acoustic output. The array of time delays may be re-configured to vary the spatial delay distribution of the device in order to generate different acoustic outputs. Also described are methods for designing or configuring such devices.

Abstract: A device for manipulating an incident acoustic wave to generate an acoustic output is described wherein the device comprises a plurality of unit cells arranged into an array, at least some of said unit cells being configured to introduce time delays to an incident acoustic wave at the respective positions of the unit cells within the array of unit cells, such that said plurality of unit cells define an array of time delays to thereby define a spatial delay distribution for manipulating an incident acoustic wave to generate an acoustic output. The array of time delays may be re-configured to vary the spatial delay distribution of the device in order to generate different acoustic outputs. Also described are methods for designing or configuring such devices.

Abstract: A device (20) for manipulating an incident acoustic wave to generate an acoustic output is described wherein the device comprises a plurality of unit cells arranged into an array, at least some of said unit cells being configured to introduce time delays to an incident acoustic wave at the respective positions of the unit cells within the array of unit cells, such that said plurality of unit cells define an array of time delays to thereby define a spatial delay distribution for manipulating an incident acoustic wave to generate an acoustic output (30). The array of time delays may be re-configured to vary the spatial delay distribution of the device in order to generate different acoustic outputs. Also described are methods for designing or configuring such devices.

Abstract: A device (20) for manipulating an incident acoustic wave to generate an acoustic output is described wherein the device comprises a plurality of unit cells arranged into an array, at least some of said unit cells being configured to introduce time delays to an incident acoustic wave at the respective positions of the unit cells within the array of unit cells, such that said plurality of unit cells define an array of time delays to thereby define a spatial delay distribution for manipulating an incident acoustic wave to generate an acoustic output (30). The array of time delays may be re-configured to vary the spatial delay distribution of the device in order to generate different acoustic outputs. Also described are methods for designing or configuring such devices.