What is the term for average intensity throughout the pulse duration?

• A. Pulse Average
• B. Spatial Peak
• C. Temporal Average
• D. Spatial Average

Answer: (A)

The idea being tested is how intensity is described for pulsed ultrasound. When a pulse is on, the energy is concentrated for a short time, and we can describe its strength by averaging that intensity over the duration of the pulse. This is the pulse average, sometimes called the temporal average during the pulse. It represents the energy delivered per unit area averaged across the time the pulse is active.

This differs from the spatial peak or spatial average, which describe how intensity is distributed across the beam’s cross-section at a single moment, or from the temporal peak, which is the maximum intensity at a location over time. So, the term that matches averaging across the pulse duration is the pulse average intensity.