A beamforming system comprises an input module, a phase-difference module, a delay distribution module, and a delay estimation module configured to make a final delay estimation based on the delay distribution. The final delay estimation is applied to align one of two selected channels and combine the two channels to obtain a signal of interest. The phase-difference module calculates phase differences for a range of frequency bins. The delay estimation module considers all possible delays derived from the phase differences, including multiples of ±2π to overcome the ambiguity in high frequency bins when the spacing between two acoustic sensors is longer than the half of the wavelengths.

An Acousto-Optic Gyroscope (AOG) consisting of a photonic integrated device embedded into two inherently matched piezoelectric surface acoustic wave (SAW) resonators sharing the same acoustic cavity is disclosed. The micromachined strain-based AOG uses the effective index of the optical waveguide due to the acousto-optic effect rather than conventional displacement sensing.

An Acousto-Optic Gyroscope (AOG) consisting of a photonic integrated device embedded into two inherently matched piezoelectric surface acoustic wave (SAW) resonators sharing the same acoustic cavity is disclosed. The micromachined strain-based AOG uses the effective index of the optical waveguide due to the acousto-optic effect rather than conventional displacement sensing.

Wind noise is suppressed from occurring in a gap between a support body and a housing body, without obstructing movement of the housing body with respect to the support body. An outer mirror device includes a mirror that assists visual recognition by an occupant of a vehicle, a visor that houses the mirror, a base that supports the visor such that the visor is capable of moving, and a seal member that is provided to the base. The seal member is separated from the visor when a speed of the vehicle is a predetermined speed or lower, and abuts the visor when the speed of the vehicle exceeds the predetermined speed so as to seal at least part of a space between the visor and the base.

Wind noise is suppressed from occurring in a gap between a support body and a housing body, without obstructing movement of the housing body with respect to the support body. An outer mirror device includes a mirror that assists visual recognition by an occupant of a vehicle, a visor that houses the mirror, a base that supports the visor such that the visor is capable of moving, and a seal member that is provided to the base. The seal member is separated from the visor when a speed of the vehicle is a predetermined speed or lower, and abuts the visor when the speed of the vehicle exceeds the predetermined speed so as to seal at least part of a space between the visor and the base.

A method for providing a broadband constant beam pattern acoustic array includes providing an array of transducers in a known three dimensional axisymmetric spherical configuration with each transducer element having an associated signal. A user can specify a far field beam pattern for the array. Weightings are calculated for each transducer in the array as being proportional to the voltage that gives the beam pattern power level associated with the bearing for each transducer. Signal power levels for each transducer are modified in accordance with the weightings. The array can be operated for receiving and transmitting signals with a constant beam pattern over a broad range of frequencies.

A method for providing a broadband constant beam pattern acoustic array includes providing an array of transducers in a known three dimensional axisymmetric spherical configuration with each transducer element having an associated signal. A user can specify a far field beam pattern for the array. Weightings are calculated for each transducer in the array as being proportional to the voltage that gives the beam pattern power level associated with the bearing for each transducer. Signal power levels for each transducer are modified in accordance with the weightings. The array can be operated for receiving and transmitting signals with a constant beam pattern over a broad range of frequencies.

There is disclosed a surface acoustic wave sensor. An interdigital transducer (IDT) and a first reflector are formed on a surface of a piezoelectric substrate. The first reflector is displaced from the IDT in a direction of acoustic wave propagation. The first reflector includes a plurality of elongate reflective elements including a first reflective element and N additional reflective elements, where N is a positive integer. A long axis of each of the reflective elements is perpendicular to the direction of acoustic wave propagation, and a distance between adjacent reflective elements along the direction of acoustic wave propagation is a linear function of distance from the first reflective element along the direction of acoustic wave propagation.

Sound direction detection devices include cylinders or other longitudinally extended structures having rotational symmetry about their longitudinal axes and multiple, rotationally equivalent resonators contained therein. Each resonator contains a microphone or other transducer that is activated when the resonator resonates.

Sound direction detection devices include cylinders or other longitudinally extended structures having rotational symmetry about their longitudinal axes and multiple, rotationally equivalent resonators contained therein. Each resonator contains a microphone or other transducer that is activated when the resonator resonates.