Real-time implementation of synthetic aperture vector flow imaging on a consumer-level tablet

• Published in: 2017 IEEE International Ultrasonics Symposium (IUS) pp. 1 - 4
• Main Authors: Di Ianni, Tommaso, Kjeldsen, Thomas Kim, Villagomez Hoyos, Carlos Armando, Mosegaard, Jesper, Jensen, Jorgen Arendt
• Format: Conference Proceeding
• Language: English
• Published: IEEE 01.09.2017
• Subjects: Apertures; Array signal processing; Graphics processing units; Imaging; Real-time systems; Ultrasonic imaging; Wireless fidelity
• ISSN: 1948-5727
• DOI: 10.1109/ULTSYM.2017.8092359

In this work, a 2-D vector flow imaging (VFI) method based on synthetic aperture sequential beamforming (SASB) and directional transverse oscillation is implemented on a commercially available tablet. The SASB technique divides the beamforming process in two parts, whereby the required data rate between the probe and back-end can be reduced by a factor of 64 compared to conventional delay-and-sum focusing. The lowered data rate enables real-time wireless transfer for both B-mode and VFI data. In the present setup, element data were acquired from a straight vessel with the SARUS research scanner and processed by a first-stage beamformer in a fixed focus. The data were subsequently transferred to an HTC Nexus 9 tablet through an ASUS RT-AC68U Wi-Fi router to simulate a wireless probe. The second-stage beamforming of the B-mode and flow data and the velocity estimation were implemented on the tablet's built-in GPU (Nvidia Tegra K1) through the OpenGL ES 3.1 API. Real-time performance was achieved with rates up to 26 VFI frames per second (38 ms/frame) for concurrent processing and Wi-Fi transmission.