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Design of ultrasonic synthetic aperture imaging systems based on a non-grid 2D sparse array
(2021-12-01)
This work provides a guide to design ultrasonic synthetic aperture systems for non-grid two-dimensional sparse arrays such as spirals or annular segmented arrays. It presents an algorithm that identifies which elements ...
Reconstrução de imagens de ultrassom usando esparsidade: métodos iterativos rápidos
(Universidade Tecnológica Federal do ParanáCuritibaBrasilPrograma de Pós-Graduação em Engenharia Elétrica e Informática IndustrialUTFPR, 2017-08-23)
This study contributes to the search for fast iterative methods for ultrasonic sparse image reconstruction. The goal is achieved in three steps: the validation of a discrete acquisition model, a comparative evaluation of ...
Improving synthetic aperture image by image compounding in beamforming process
(2011-11-10)
In this work, signal processing techniques are used to improve the quality of image based on multi-element synthetic aperture techniques. Using several apodization functions to obtain different side lobes distribution, a ...
Improving ultrasonic imaging of aluminum plates using phase modulation
(2020-01-01)
Conventional techniques for ultrasonic image beamforming use amplitude information to produce the im-ages. Although amplitude images can be obtained with high quality, they can also present limitations regarding dead zone, ...
Sparse arrays and image compounding techniques for non-destructive testing using guided acoustic waves
(2013-06-01)
Piezoelectric array transducers applications are becoming usual in the ultrasonic non-destructive testing area. However, the number of elements can increase the system complexity, due to the necessity of multichannel ...
Sparse arrays and image compounding techniques for non-destructive testing using guided acoustic waves
(2013-06-01)
Piezoelectric array transducers applications are becoming usual in the ultrasonic non-destructive testing area. However, the number of elements can increase the system complexity, due to the necessity of multichannel ...
Ultrasonic Image Compounding Method Based on the Instantaneous Phase Image
(Ieee, 2016-01-01)
The quality of ultrasonic images depends on array configuration, image beamforming algorithm, propagation modes and signal-to-noise ratio. Some alternatives to improve image quality are related to the use of coherence ...
Geração de imagens por ultrassom utilizando as técnicas sparse arrays e plane wave
(Universidade Tecnológica Federal do ParanáCuritibaBrasilPrograma de Pós-Graduação em Engenharia Elétrica e Informática IndustrialUTFPR, 2018-12-13)
Nowadays, the major difficulties to improve the quality of the images using the ultrasonic techniques are related to the high number of shots used for transducer excitation, large quantities of storage data and the necessary ...
Instantaneous Frequency Image
(2021-05-01)
The instantaneous frequency (IF) image is proposed in this work. It is obtained by the differentiation of the instantaneous phase (IP) image, which in turn is calculated by replacing the amplitude information with the IP ...