Table 2 Transducers used in the study. The properties of each transducer were provided by the manufacturer. The bandwidth was measured by − 6 dB width of the Fourier spectrum of the incident wave obtained from the pulse-echo test. The beamwidth at focus was estimated by \(2\times wavelength\times (f-number)\).

From: Quantitative imaging of ultrasound backscattered signals with information entropy for bone microstructure characterization