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In this work we present the evaluation results of our 3D sonar camera system. The system consists of a matrix antenna array with 1024 single transducer elements and our in house developed DiPhAS sonar beamformer - a 128 channel FPGA-based beamforming system with a 1:8 multiplexing device for each channel. The system is designed to be applicable to ROV and AUV systems for real-time volumetric imaging in a deep sea environment. Defocused excitation of the transducer array is used to achieve a sound field opening angle of up to 40° in lateral and elevational direction. The antenna's sound field can be adjusted electronically in order to increase either the imaged area or the image contrast in a specific area of interest. Different filter algorithms working on a raw data basis have been implemented in order to suppress image artifacts which occur during the reconstruction process. Measurements on different phantoms have been performed in order to prove the real-time imaging as well as spatial resolution capabilities of the camera system

Digital ultrasound probes include the entire analog frontend in their enclosing and are equipped with a standard digital link. This enables to build very cost-effective ultrasound systems as they can be simply connected to a commodity device, such as a desktop PC, tablet or smartphone, running an ultrasound imaging application. Up to now, digital probes have been mainly demonstrated for low-end ultrasound applications and are currently limited to a small number of frontend channels (typically 16). In addition, the available bandwidth at the digital interface (less than 10 Gb/s) limits these devices only to basic imaging modalities. In this work, we present an imaging platform built with a digital 64-channel ultrasound probe that supports ultrafast imaging. Our digital probe, called LightProbe, utilizes a 64element phased array without multiplexing and incorporates a 64-channel 100 Vpp TX/RX stage providing a sample rate up to 32.5 MS/s @ 12 bit. The probe features an optical link interface achieving 25 Gb/s on a standard fiber cable. A Xilinx Artix 7 FPGA is integrated in the probe to manage the optical interface and to provide a high-degree of configurabilty. To the best of our knowledge, this is the first digital probe capable of compounded plane wave imaging. We capture plane waves with peak and average rate of 4.9 kHz and 2 kHz respectively, with a peak link load of 15.36 Gb/s, while consuming just 9.25 W.

Object recognition, advanced distance measurements and other inspection scenarios have an increasing demand in versatile airborne ultrasonic phased arrays for acoustic scanning without moving parts. Based on cellular polymer film with high piezoelectric effect we have realized an array structure with a pitch of 0.5 mm and element length of 10 mm. The working frequency of the material was measured to 250 kHz. From pointspread simulation with the small ratio of pitch/wavelength of 0.35 we could expect good beam steering and focusing characteristics. A first test array was realized and characterized. There was good agreement between measurement results and simulations. Additionally a low frequency electronic beamformer system was developed for generating the first B-image of an airborne phased array. Measurements showed that cellular polymer is a well suitable material for airborne applications. It can easily be structured to the desired shape. It allows especially the realization of Phased Arrays for applications like surface or profile measurement, access control, attendance check, robot guidance etc.. New airborne array types like linear, phased, curved or circular arrays are now possible. Also single element transducers with varying apertures (rectangular, oval), shaped apertures (focusing (line-or point-focusing), defocusing) or combinations of both are possible.

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