Blood is a medium consisting of several types of cells suspended in a fluid medium
known as plasma. The main cell concentration is made up of red blood cells (RBCs), or erythrocytes. The scattering medium in the blood plasma is mainly these red
blood cells, which have a diameter of about 6 − 8µm [52]. As the scattering size is
much smaller than the wavelength used in medical ultrasound imaging, the scattering
properties will exhibit Rayleigh characteristics. This means that the sound scattered
from blood follows a frequency dependency law for the scattering power of f
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