ULA-OP 256: A 256-Channel Open Scanner for Development and Real-Time Implementation of New Ultrasound Methods

Abstract

Open scanners offer an increasing support to the ultrasound researchers who are involved in the experimental test of novel methods. Each system presents specific performance in terms of number of channels, flexibility, processing power, data storage capability, and overall dimensions. This paper reports the design criteria and hardware/software implementation details of a new 256-channel ultrasound advanced open platform. This system is organized in a modular architecture, including multiple front-end boards, interconnected by a high-speed (80 Gb/s) ring, capable of finely controlling all transmit (TX) and receive (RX) signals. High flexibility and processing power (equivalent to 2500 GFLOP) are guaranteed by the possibility of individually programming multiple digital signal processors and field programmable gate arrays. Eighty GB of on-board memory are available for the storage of prebeamforming, postbeamforming, and baseband data. The use of latest generation devices allowed to integrate all needed electronics in a small size ( 34 cm ×30 cm ×26 cm). The system implements a multiline beamformer that allows obtaining images of 96 lines by 2048 depths at a frame rate of 720 Hz (expandable to 3000 Hz). The multiline beamforming capability is also exploited to implement a real-time vector Doppler scheme in which a single TX and two independent RX apertures are simultaneously used to maintain the analysis over a full pulse repetition frequency range.

Efficient Sample Delay Calculation for 2-D and 3-D Ultrasound Imaging

“…The challenge is to do so in a manageable hardware footprint; for example, the academic SARUS [25] system, which is very advanced but only supports up to 1024-element matrix probes, runs on 320 FPGAs. The more recent ULA-OP platform [26] uses 8 high-end FPGAs and 16 DSPs to support only 256-channel beamforming.…”

Riding the Plane Wave: Considerations for In Vivo Study Designs Employing High Frame Rate Ultrasound

“…Such a rapid surge of interest is technically attributed to two engineering innovation trends. First, in the past decade, reconfigurable ultrasound scanners have become more prevalent [19][20][21][22][23][24], as opposed to non-programmable clinical systems that are designed via an embedded system approach [25]. These open-architecture systems have enabled researchers to readily implement different variants of unfocused pulsing sequences that are essential for realizing HiFRUS [26].…”

“…Worth particular mention are the in-house systems built at the Technical University of Denmark [19,23], the University of Florence [21,24], the Langevin Institute in Paris [35], and the Polish Academy of Sciences [36]. A few commercially available research platforms also allow similar HiFRUS implementations, such as Analogic Ultrasound (Peabody, MA, USA) [37], Verasonics (Kirkland, WA, USA) [22], US4US (Warsaw, Poland), and Cephasonics (Santa Clara, CA, USA).…”

“…While few clinical ultrasound systems have the capability for HiFRUS imaging, certain research systems allow for customization of the transmit firing sequence of every array channel and the acquisition of channel-domain data for customized algorithmic processing [19][20][21][22][23][24][35][36][37]. In general, HiFRUS imaging studies rigorously report the technical specifics of the experimental methods, such as the array pitch, probe frequency, transmit pulse duration, pulse repetition frequency, steering angles, and spherical source positioning.…”

Localisation of multiple non-isolated microbubbles with frequency decomposition in super-resolution imaging

“…The ULA-OP system (MSD Lab, University of Florence, Italy) was used to acquire data using the LA332 imaging transducer (Esaote, Firenze, Italy) [9]. This is a 144 linear array probe with a −6 dB bandwidth ranging from 2−7.5 MHz and a 254 µm element pitch.…”