A speech recognition device is provided. The speech recognition device includes at least one microphone configured to receive a sound signal from a first sound source, and at least one processor configured to determine a direction of the first sound source based on the sound signal, determine whether the direction of the first sound source is in a registered direction, and based on whether the direction of the first sound source is in the registered direction, recognize a speech from the sound signal regardless of whether the sound signal comprises a wake-up keyword.

Detecting sound sources in a physical space-of-interest is challenging due to strong ego-noise from micro aerial vehicles (MAVs) propeller units, which is both wideband and non-stationary. The present subject matter discloses a system and method for acoustic source localization with aerial drones. In an embodiment, a wideband acoustic signal is received from an aerial drone. Further, the wideband acoustic signal is splitted into multiple narrow sub-bands having cells. Moreover, from a measurement position corresponding to each of the multiple narrow sub-bands, power in each of the cells is measured by forming a beam to each of the cells. In addition, intra-band and inter measurement fusion of the measured power at each of the cells is performed. Also, geo-location of an acoustic source corresponding to the wideband acoustic signal is identified upon performing intra-band and inter measurement fusion of the measured power.

The direction of an acoustic wave can be determined using a single microphone. The single microphone can be operatively positioned within an interior of a resonator. The resonator can include a body that includes an aperture, such as a slit, which allows communication between the interior and an exterior of the resonator. The resonator can be configured to rotate. The single microphone can be configured to acquire sound data of an incident acoustic wave. One or more processors can be operatively connected to the single microphone. The one or more processors can be configured to determine a direction of the incident acoustic wave based on the acquired sound data.

A method and system for enhancing a target sound signal from multiple sound signals is provided. An array of an arbitrary number of sound sensors positioned in an arbitrary configuration receives the sound signals from multiple disparate sources. The sound signals comprise the target sound signal from a target sound source, and ambient noise signals. A sound source localization unit, an adaptive beamforming unit, and a noise reduction unit are in operative communication with the array of sound sensors. The sound source localization unit estimates a spatial location of the target sound signal from the received sound signals. The adaptive beamforming unit performs adaptive beamforming by steering a directivity pattern of the array of sound sensors in a direction of the spatial location of the target sound signal, thereby enhancing the target sound signal and partially suppressing the ambient noise signals, which are further suppressed by the noise reduction unit.

A system and method for tracking aircraft, helicopters and/or other objects at an airfield using acoustics of the aircraft, helicopters and/or other objects. A method receives first acoustical data at a first sensor and second acoustical data is also received at a second sensor. The first and second sensors may be carried by a first structurally supportive body member. Based at least in part on the first acoustical data and the second acoustical data a range and a bearing of the aircraft is determined from a predetermined location at the airfield. The range and bearing can be determined by using a beam forming algorithm. Based on the range and the bearing, the method displays the location the aircraft on a display.