For classification of different attenuation regions, this paper presents an envelope histogram method and thresholding procedure.
To improve the low S/N ratio due to attenuation, a narrowband technique using burst pulses was employed. And the histogram of 4-scan line data was averaged in each slided window to reduce the inherent variance by random scatterrers in soft tissue.
Experiments were carried out with tissue mimicking phantoms in water. As a result, two regions within 4.6cm depth with different attenuation coefficients were segmented. And the attenuation coefficient in each region was calculated with the NSR method.