Pulse Length Sets Axial Resolution - Biophysical Ultrasound: Echo Timing and Acoustic Interfaces Step by Step

A finite pulse length limits axial claims. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.

highlighted = computed this step

Two cycles occupy two wavelengths

A 2 cycle pulse with wavelength 4 meters occupies 8 meters.

2\cdot 4\ \text{m}=8\ \text{m}

Axial resolution is half the pulse length in this model

Half of pulse length 8 meters gives a resolution limit of 4 meters.

\Delta d_{\min}=\frac{8}{2}=4\ \text{m}