Ultrasonic ranging systems and methods that emit coded bursts and correlate transduced acoustical echoes of the bursts with a receive template characterizing a burst code to determine time-of-flight information use receive templates of time-variable length to improve short-range object detection. The template length is based on a time index measured from the start of the burst emission. The detection can account for a dead zone of transducer ringing following a burst. A time-variable gain that is also based on the time index can be applied to the correlated signal. The length and gain can be adjusted with reduced temporal frequency to reduce computation cost.

A survey system including a transmitter, receiver, projector array and hydrophone array transmits and receives sound waves to perform one or more survey missions.

An approach for providing a lower cost real time location system in less trafficked areas of a building. This approach uses on-board audio capabilities of a mobile device to receive a room response trace resulting from a self-generated acoustic signal. By comparing the room response trace to a modeled room response trace, the location of the mobile device is determined.

A survey system including a multibeam echo sounder having a single projector array and a single hydrophone array constructs a multi-signal message and deconstructs a corresponding multi-signal echo to substantially simultaneously perform multiple survey missions.

Systems and methods to detect objects and associated properties may be performed by an aerial vehicle having one or more propellers and one or more microphones. The aerial vehicle may emit propeller noise patterns via the propellers during operation, and the aerial vehicle may receive echoes of the propeller noise patterns via the microphones. Based on the emitted noise patterns and received echoes, the aerial vehicle may detect objects and associated properties within an environment of the aerial vehicle. In addition, the aerial vehicle may emit encoded propeller noise patterns via the propellers during operation to communicate with other aerial vehicles, and other aerial vehicles may receive the encoded propeller noise patterns via microphones. Using such encoded propeller noise patterns, a plurality of aerial vehicles may communicate and/or coordinate operations with each other.

A target detection and/or high resolution RF system is provided herein in which the resolution of a legacy target angle detection (direction of arrival) system is improved without any change to the existing hardware of the legacy target detection system. Rather, the target detection and/or high resolution RF system can apply virtual aperture postprocessing to reflected signals to achieve improvements in the detection of one or more targets.

A phase array acoustic device using array of horns and optional faceplates is presented. Said horn phased-array acoustic device can be used as a passive sensor, a sound projector, or both (sonar).

It is shown that by correct selection of the fill-factor and apodization faceplate, grating-lobes and side-lobes cab be greatly reduced.

An optional use of acoustic valves as phase-shifter in the wave domain to improve Signal to Noise Ratio is presented.

An optional aperiodic tiling of the horns' mouth to reduces aliasing is presented.

A survey system including a multibeam echo sounder having a single projector array and a single hydrophone array constructs a multi-signal message and deconstructs a corresponding multi-signal echo to substantially simultaneously perform multiple survey missions.

A method is accordingly provided for operating an ultrasonic sensor, a plurality of measuring cycles being successively carried out. In each measuring cycle—an electroacoustic transducer of the ultrasonic sensor is excited using an excitation pulse, causing it to mechanically oscillate, as a result of which a measuring signal is transmitted by the transducer, an echo signal is received by the transducer, and a piece of object information is ascertained from the echo signal. The frequency curve of the excitation pulse is differentiated into two measuring cycles successively carried out at least at the end of the frequency curve. The ascertained pieces of object information from at least two measuring cycles are compared with one another and an interference is identified as a function of the result of the comparison.

An obstacle detection sensor includes: a controller configured to determine a detection condition of an obstacle on a road; a distance sensor unit configured to acquire distance information by oscillating a vibration wave and receiving a reflected wave of the oscillated vibration wave; a communication unit configured to communicate with an outside to acquire road surface information; and a storage unit configured to store detection relationship information for identifying the obstacle based on the distance information, in which the controller compares the detection relationship information read from the storage unit with the distance information and the road surface information acquired from the distance sensor unit and the communication unit to determine the detection condition.