Visibility of a surface in turbid water can be provided using a sonar array, a plurality of acoustic mirrors, and a computing device. The sonar array can be configured to form an ultrasonic beam with a lateral dimension of a point spread function and an elevational dimension of the point spread function. The plurality of acoustic mirrors can be configured to shape and steer the point spread function. The computing device can include a non-transitory memory storing instructions and a processor configured to access the non-transitory memory and execute the instructions to sweep the ultrasound beam in the lateral dimension and the elevational dimension by moving at least one of the plurality of acoustic mirrors. Sweeping the ultrasound beam allows the processor to acquire a three dimensional data set that is used to create a projection-style reconstruction of a location in the water.

Technologies for correcting beamformed data are disclosed. A sonar computing device receives, at two or more sets of two-dimensional (2D) subarrays of a multi-element detector array, raw data representing a three-dimensional (3D) volumetric view of a space. A first set of subarrays of the two or more sets of subarrays includes elements of the detector array along a first direction. A second set of subarrays of the two or more sets of subarrays includes elements of the detector array along a second direction. The raw data is subdivided into slices and beamformed. The beamformed data is corrected by, per slice, obtaining first phase data from the first set, obtaining second phase data from the second set, correcting a beam position of each beam in the first and second directions per voxel based on the first and second phase data, and interpolating the corrected beam positions to an output grid.

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 marine electronic device is provided including a user interface comprising a display, a marine electronic device processor, and a memory. The memory includes computer program code configured to cause the marine electronic device to receive sonar return data from at least one transducer element configured to transmit sound waves into a body of water, receive the sonar return signals from the body of water, and convert the sonar return signals into sonar return data. The computer program code is further configured to cause the marine electronic device to generate one or more sonar images based on the sonar return data, identify one or more degraded performance characteristics associated with the sonar return data or the one or more sonar images, and cause an alert based on identification of the one or more degraded performance characteristics.

A sonar-integrated IoT device, the IoT device including one or more sonar sensor modules (101), corresponding to information acquisition in different spatial directions; the IoT device is in communication connection with an external signal processing unit through a wireless network, and sends unprocessed or preliminarily processed spatial information to the signal processing unit. The advantages of the invention include: simple and flexible arrangement of sonar sensor module (101) nodes, which are integrated with wireless IoT devices such that spatial information may be acquired locally; and at the same time, ease of implementation of large interval arrangement and large quantity arrangement of sonar sensor modules (101), covering a variety of spatial locations, thereby providing wide coverage of spatial detection range, and acquisition of abundant signal samples, such that better spatial information extraction algorithms may be implemented in the signal processing unit.

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.

This document describes spatial and temporal processing of ultrasonic-sensor detections for mapping in vehicle-parking-assist functions. Specifically, spatial intersections, which are determined from a pair of neighboring ultrasonic sensors having ultrasonic detections at substantially the same time, can address latency issues associated with temporal intersections and can be determined without the vehicle moving. Temporal intersections can address situations when one sensor of the pair of neighboring ultrasonic sensors has an ultrasonic detection while the other sensor does not. Using both the spatial and temporal intersections provides high accuracy for angular information, which enables enhanced mapping and efficient performance of vehicle-parking-assist functions.

Systems and methods for enhanced blazed array and/or phased array sonar systems are described herein. In one aspect, a sonar system includes a blazed sonar array and/or phased sonar array having: at least one transducer connected to a housing of a vehicle; a transmitter, in electrical communication with the at least one transducer, causing the transducer to emit at least one sonar signal, the sonar signal having a Doppler sharpening pulse length and the vehicle having a Doppler sharpening velocity; a receiver, in electrical communication with the at least one transducer, for receiving signals from at least one transducer, the received signals corresponding to acoustic signals captured by the at least one transducer; and a processor, in electrical communication with the transmitter and receiver, arranged to control the Doppler sharpening pulse length and generate a 3D image based on the received signals, Doppler sharpening pulse length, and Doppler sharpening velocity.

For an ultrasound image acquired by an ultrasound detection system, background data with small noises are first filtered. Next, a binary image is generated by performing image binarization on the noise-reduced ultrasound image based on a first threshold value, wherein the binary image contains information associated with the body of high-echo foreground images in the ultrasound image. An output image is generated by performing foreground expansion on the binary image based on the pixel value of the ultrasound image and a second threshold value smaller than the first threshold value, wherein the output image contains information associated with not only the body but also the outline of high-echo foreground images in the ultrasound image. An improved ultrasound image is generated by performing a post-processing on the ultrasound image according to information of foreground and non-foreground region in the output image.

A small aperture acoustic velocity sensor and a method for velocity measurement are disclosed. In one aspect, the disclosed technology uses spatially-shifted sub-arrays for projection and/or hydrophone receipt and cross-correlation of successive pulses to improve correlation and reduce bias. The spatial shift can be created physically by selection of groups of elements or virtually by weighting the contributions of fixed sub-arrays. Spatial modulation can be used to form a projected signal and measured spatial phase of slope across the set of sub-arrays allows correction of both long- and short-term errors. The disclosed technology uses spatial and/or temporal interpolation.