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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