Simulated ultrasound CFM data for cross-correlation estimation
The RF data was obtained from simulating a parabolic flow by using the
Field
II program. The simulation generates 10 RF signals in the same position
with Tprf seconds between the RF signals, which are then grouped
in a single Matlab file. This is done for all scan position. Twenty scan
positions were generated starting from the left side of the phantom and
moving to the right in increments of 2 mm. The linear scan of the phantom
was made with a 192 element transducer using 64 active elements with a
Hanning apodization in transmit and a dynamic Hanning apodization in receive.
A single transmit focus was placed at 60 mm, and receive focusing was done
at 2 mm intervals from 10 mm from the transducer surface. The resulting
signals have then been used in a standard cross-correlation estimator for
finding the velocity image.
The resulting color flow image is shown below.
CFM image of vessel with parabolic flow.
The data for the simulation are given below:
Transducer: |
5 MHz, linear array probe with 64 active elements |
Pulse repetition frequency: |
10 kHz |
Angle between flow and beam: |
45° |
Ultrasound excitation pulse: |
1 cycles at 5 MHz |
Sampling frequency: |
25 MHz |
Resolution: |
16 bits samples, 1 volts maximum amplitude |
Vessel radius: |
5 mm |
Depth of first sample point: |
30 mm from transducer surface |
Depth of last sample point: |
90 mm from transducer surface |
Center of vessel: |
z=60 mm at x=0 mm |
Radius of vessel: |
5 mm |
Peak velocity in vessel: |
0.5 m/s |
The RF data can be obtained from the ftp-server from the directory:
https://courses.healthtech.dtu.dk/22485/files/ult_data/simulation/sim_cfm_cross/
The Matlab variable with the data is called data. One column
in one of the data files contains the received RF signal for one pulse
emission. The matrix, thus, contains 10 columns for of RF data in one direction
from which the velocity distribution can be found along that direction.
The phantom has also scanned as a B-mode image with 60 lines starting
a lateral position of -20 mm and then using an increment of 2/3 mm per
line. The data for the B-mode image can be found in:
https://courses.healthtech.dtu.dk/22485/files/ult_data/simulation/sim_cfm_cross/b_mode.mat
The file contains a matrix with 60 columns; one for each line in the
image. The data starts 30 mm from transducer surface and the sampling frequency
is 25 MHz.
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