  Ultrasound attenuation coefficient estimation (ACE) can be utilized to
quantify liver fat content, offering significant diagnostic potential in
addressing the growing global public health issue of non-alcoholic fatty liver
and other chronic liver diseases. Among ACE methods, the reference frequency
method (RFM) proposed recently possesses the advantages of being
system-independent and not requiring reference phantom. However, the presence
of large oscillations in frequency power ratio decay curves leads to unstable
ACE results with RFM, originating from noise as well as constructive and
destructive interference in the backscattered signal's power spectrum. To
address this issue, we propose an improved RFM version where a single-scatterer
power spectrum estimator is incorporated to restore interference free
single-scatterer power spectrum, thereby reducing oscillations in the frequency
power ratio decay curves and greatly improving the accuracy of ACE.
