Comparing interpolation schemes in dynamic receive ultrasound beamforming

Synthetic aperture focusing for a single-element transducer undergoing helical motion

“…The lines clearly show a reduction in side-lobes as the number of axial samples increases from 1,500 to 20,000 per line. The side-lobes are a result of errors in the interpolation step, which can be circumvented by either increasing the sampling density or by choosing a more advanced interpolation scheme [21]. To reduce the sidelobes below -60 dB a minimum of ≈ 10,000 samples per line are required.…”

Scalable intersample interpolation architecture for high-channel-count beamformers

“…This method only picks out the nearest neighbor sample and leads to large sidelobes in the point spread function [3]. Some form for interpolation is, thus, needed.…”

“…Another way for achieving focusing precision is to use interpolation between the input samples. Experiments have been done with linear, polynomial and bandpass filtering interpolation [3]. Linear interpolation is often used, since it requires the least amount of hardware compared to other interpolation techniques.…”

Three-dimensional synthetic aperture focusing using a rocking convex array transducer

“…A drawback of this method is that one must either improve the resolution in only one dimension, or save an intermediate data set. In addition, performing the beamforming in two steps will put larger emphasis on the need for adequate interpolation routines to avoid high side-lobes [12]. This paper uses a method that allows a time-of-flight (ToF) value to be calculated for a given 3-D point.…”

“…The 2-step method also has to sample densely in the first step to reduce interpolation errors, which can give rise to high side-lobes. Alternatively, an advanced interpolation method can be applied in the second beamforming step [12]. This paper presents the feasibility of implementing a direct 3-D time-of-flight (ToF) calculation on a rocking convex array for use with SAF to improve the elevation resolution.…”