TY  JOUR
T1  A Transverse Oscillation Approach for Estimation of ThreeDimensional Velocity Vectors, Part I: Concept and Simulation Study
AU  Pihl, Michael Johannes
AU  Jensen, Jørgen Arendt
PY  2014
Y1  2014
N2  A method for 3D velocity vector estimation us

ing transverse oscillations is presented. The method employs
a 2D transducer and decouples the velocity estimation into
three orthogonal components, which are estimated simultane

ously and from the same data. The validity of the method is
investigated by conducting simulations emulating a 32 × 32
matrix transducer. The results are evaluated using two per

formance metrics related to precision and accuracy. The study
includes several parameters including 49 flow directions, the
SNR, steering angle, and apodization types. The 49 flow direc

tions cover the positive octant of the unit sphere. In terms of
accuracy, the median bias is −2%. The precision of
v
x
and
v
y
depends on the flow angle
β
and ranges from 5% to 31% rela

tive to the peak velocity magnitude of 1
m/s. For comparison,
the range is 0.4 to 2% for
v
z
. The parameter study also reveals,
that the velocity estimation breaks down with an SNR between
−6 and −3
dB. In terms of computational load, the estimation
of the three velocity components requires 0.75 billion floating
point operations per second (0.75
Gflops) for a realistic setup.
This is well within the capability of modern scanners.
AB  A method for 3D velocity vector estimation us

ing transverse oscillations is presented. The method employs
a 2D transducer and decouples the velocity estimation into
three orthogonal components, which are estimated simultane

ously and from the same data. The validity of the method is
investigated by conducting simulations emulating a 32 × 32
matrix transducer. The results are evaluated using two per

formance metrics related to precision and accuracy. The study
includes several parameters including 49 flow directions, the
SNR, steering angle, and apodization types. The 49 flow direc

tions cover the positive octant of the unit sphere. In terms of
accuracy, the median bias is −2%. The precision of
v
x
and
v
y
depends on the flow angle
β
and ranges from 5% to 31% rela

tive to the peak velocity magnitude of 1
m/s. For comparison,
the range is 0.4 to 2% for
v
z
. The parameter study also reveals,
that the velocity estimation breaks down with an SNR between
−6 and −3
dB. In terms of computational load, the estimation
of the three velocity components requires 0.75 billion floating
point operations per second (0.75
Gflops) for a realistic setup.
This is well within the capability of modern scanners.
U2  10.1109/TUFF c .2013.006237
DO  10.1109/TUFF c .2013.006237
M3  Journal article
VL  61
SP  1599
EP  1607
JO  I E E E Transactions on Ultrasonics, Ferroelectrics and Frequency Control
JF  I E E E Transactions on Ultrasonics, Ferroelectrics and Frequency Control
SN  08853010
IS  10
ER 