Many explanation related to measurement technique, intensity, ultrasonics, and bandwidth are described inside this paper. This paper contains explanation like transducer, hydrophone, transducers, and measurements.
Inside the paper the reader can find info like high frequency transducers, resolution, the acoustic wavelength, and acoustic pressure. Here are excerpted from the paper:
simple technique for the determination of the spatial and temporal transmit-receive ﬁeld distributions of spherically focused high-frequency transducers is described. Instead of a point-like target, tungsten wires (line-like targets) with diameters less than the acoustic wavelength are used as pulse-echo targets. Spatial and temporal ﬁeld quantities were determined for spherically focused transducers in the frequency range from 3 to 17 MHz, and a comparison with hydrophone measurements showed that both techniques yielded comparable results for the lowfrequency transducer.
Giving more content, the paper explains info things like pulse, ultrasonics ferroelectrics, and wavelength.