title: Development of a Low-Complexity, Cost-Effective Digital Beamformer Architecture for High-Frequency Ultrasound Imaging.
abstract: This paper presents a low-complexity, cost-effective digital beamformer architecture for a high-frequency ultrasound imaging system. The proposed beamformer uses a lookup table and linear interpolation methods for computing the dynamic receive focusing delays and a postfiltering technique to minimize hardware complexity. In the postfiltering technique, channel radio-frequency data having the same fractional delay (i.e., 16f0resolution) are aggregated prior to interpolation. Thus, only four polyphase structure filters are required in the developed beamformer. In addition, a quadrature bandpass filter that generates an analytic signal is utilized as an interpolation filter; this allows decimation during beam formation and a reduction in computational complexity. The proposed method was evaluated through a 20- [Formula: see text] wire phantom experiment, and the -6-dB lateral and axial resolutions obtained therein were measured and compared with those obtained using a conventional method. The same lateral (165 [Formula: see text]) and axial (80 [Formula: see text]) resolutions at a depth of 5.6 mm were obtained using both the methods, and the proposed method could reduce the beamforming points (i.e., computational complexity) by a factor of the decimation factor (≥4). Images from an excised bovine eye were captured; they showed that the proposed beamformer identified fine anatomical structures such as cornea or iris without compromising the spatial resolution and reduced the computational complexity.
authors.forename: Changhan
authors.initials: C
authors.lastname: Yoon
authors.forename: Hyung Ham
authors.initials: HH
authors.lastname: Kim
authors.forename: K Kirk
authors.initials: KK
authors.lastname: Shung
mesh_terms: D007091:Image Processing, Computer-Assisted / Q000379:methods*; D019047:Phantoms, Imaging; D014159:Transducers; D014463:Ultrasonography / Q000295:instrumentation* / Q000379:methods*