Design and assessment of an electrodynamic loudspeaker used in a variable acoustic lining concept

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Air traffic noise emissions are responsible for a significant part of the overall environmental noise, especially in the vicinity of airports. Exposure to environmental noise is known to negatively impact health and to be associated with cardiovascular dis ...

Niobium nitride (NbN) is a particularly promising material for quantum technology applications, as it shows the degree of reproducibility necessary for large-scale superconducting circuits. We demonstrate that resonators based on NbN thin films present a o ...

The SALUTE project aims at evaluating performance of electroacoustic metasurface, employing a surface array of controlled electroacoustic actuators, for smart acoustic lining under grazing turbulent flow to be used in UHBR Technologies Engines. Theoretical ...

Controlling audible sound requires inherently broadband and subwavelength acoustic solutions, which are to date, crucially missing. This includes current noise absorption methods, such as porous materials or acoustic resonators, which are typically ineffic ...

This work presents the study of suspended Y-cut Lithium Niobate shear bulk acoustic resonators for wide band filter applications in the frequency range of 3.5-4.5GHz. The resonators consist of a Lithium Niobate film with Aluminum top interdigitated electro ...

This paper presents an acoustic impedance control architecture for an electroacoustic absorber combining both feedforward and feedback microphone-based strategies on a current-driven loudspeaker. Feedforward systems enable good performance for direct imped ...

This work reports on the design and fabrication of fundamental shear horizontal (SH0) mode acoustic resonators based on a suspended lithium niobate (LNO) film at 1.04 GHz. Due to the large e16 piezoelectric coefficient of YX36 degrees.-cut LNO, fabricated ...

Environmental noise, mostly related to human activities, has an immense impact on public health. The development of noise reduction technologies is paramount in addressing this problem. Because of practical and economic reasons, a compact, broadband, light ...

Sound absorption at low frequencies still remains a challenge in both scientific research and engineering practice. Natural porous materials are ineffective in this frequency range, as well as acoustic resonators which present too narrow bandwidth of absor ...

Thin-film lithium niobate (LNO) has been identified as a promising material platform for enabling high electromechanical coupling and low-loss piezoelectric resonators for filtering applications. In this work, the design and fabrication of fundamental shea ...

RF MEMS piezoelectric acoustic resonators are the essential building blocks for RF filters used in RF front-end modules for wireless mobile communication due to their compact size in the MHz-GHz frequency range, high Quality factors and large relative band ...

The acoustics of a room often refer to the quality of the room in terms of sound recording as well as sound reproduction. At low frequencies, where the wavelengths are of the same order of magnitude with the dimensions of the room, due to the standing wave ...

We present the fabrication of 570-mu m-thick millimeter-sized soda-lime-silicate float-glass blocks with a 1-mu m-thick AlN thin-film piezoelectric transducer sandwiched between thin metallic electrodes and deposited on the top surface. The electromechanic ...

In this thesis, the electromagnetic wave propagation is studied in nonstationary-medium scenarios. The electromagnetic fields under material time-modulation are shown to conserve their momentum but not their energy. The mathematical foundations and analysi ...

We introduce an active concept for achieving acoustic metasurfaces with steerable reflection properties, effective over a wide frequency band. The proposed active acoustic metasurface consists in a surface array of subwavelength loudspeakers diaphragms, ea ...

This paper deals with active sound attenuation in lined ducts with flow and its application to duct modes damping in aircraft engine nacelles. It presents an active lining concept based on an arrangement of electroacoustic absorbers flush mounted in the du ...

This article presents a Siren Disk proof of concept for the dynamic excitation of pressure probes, and a method to reconstruct distorted signals due to pneumatic channels. Constraints in sensor installation require placing a pressure transducer distant fro ...

Elastic vibrations in subwavelength structures have gained importance recently in fundamental light–matter studies and various optoacoustic applications. Existing techniques have revealed the presence of distinct acoustic resonances inside silica microwire ...

Low-frequency electroacoustic absorbers have recently been developed as a solution for the modal equalisation. Firstly investigated in waveguides, the technique consists in matching the acoustic impedance at a closed-box loudspeaker diaphragm to the charac ...

This paper proposes a hybrid impedance control architecture for an electroacoustic absorber, that combines an improved microphone-based feedforward control with a currentdriven electrodynamic loudspeaker system. Feedforward control architecture enables sta ...

Design and assessment of an electrodynamic loudspeaker used in a variable acoustic lining concept

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Robust tunable acoustic impedance control on electroacoustic resonators for aircraft noise reduction

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Smart acoustic lining for UHBR technologies engine: from the design of an electroacoustic metasurface to experimental characterization under flow

Ultrabroadband sound control with deep-subwavelength plasmacoustic metalayers

Toward Band n78 Shear Bulk Acoustic Resonators Using Crystalline Y-Cut Lithium Niobate Films With Spurious Suppression

Robust direct acoustic impedance control using two microphones for mixed feedforward-feedback controller

Transversal Spurious Mode Suppression in Ultra-Large-Coupling SH0 Acoustic Resonators on YX36 degrees-Cut Lithium Niobate

Plasma-based Electroacoustic Actuator for Broadband Sound Absorption

PID-like active impedance control for electroacoustic resonators to design tunable single-degree-of-freedom sound absorbers

Optimization of Edge Profile for Improved Anti-Resonance Quality Factor in Lithium Niobate SH0 Resonators

Development of Thin Film Lithium Niobate Shear Bulk Acoustic Wave Resonators

Sound Field Reconstruction in a room through Sparse Recovery and its application in Room Modal Equalization

Fabrication, Characterization, and Simulation of Glass Devices with AlN Thin-Film Transducers for Excitation of Ultrasound Resonances

Electromagnetic waves under nonstationary conditions, the connection with parity-time symmetry and studies on resonant systems

Toward Wideband Steerable Acoustic Metasurfaces with Arrays of Active Electroacoustic Resonators

Duct modes damping through an adjustable electroacoustic liner under grazing incidence

Non-linear transfer function identification of pressure probes using Siren Disks

Local activation of surface and hybrid acoustic waves in optical microwires

On the Optimisation of Multi-Degree-of-Freedom Acoustic Impedances of Low-Frequency Electroacoustic Absorbers for Room Modal Equalisation

Broadband Low-Frequency Electroacoustic Absorbers Through Hybrid Sensor-/Shunt-Based Impedance Control