Compared to CW Doppler, the intensity of PW Doppler is what?

• A. Greater
• B. Lesser
• C. Equal
• D. Variable

Answer: (A)

Doppler signal intensity is tied to how energy is delivered. Pulsed-wave Doppler sends energy in short bursts, concentrating energy into brief pulses. That means the acoustic energy available during each pulse—and the backscattered echoes it generates—can be higher than the continuous emission of continuous-wave Doppler. Even though the pulsed system has a lower duty cycle and thus a lower average exposure over time, the instantaneous intensity and the resulting Doppler signal per pulse are greater. So, compared with continuous-wave Doppler, pulsed-wave Doppler produces a stronger Doppler signal (higher intensity) during the pulse.