Aliasing ____ occur with CW Doppler.

Aliasing ____ occur with CW Doppler.

• A. Occurs
• B. Does not occur
• C. May occur
• D. Always occurs

Answer: (B)

Aliasing in Doppler studies comes from sampling the signal at a finite rate. In pulsed Doppler, the signal is sampled at the pulse repetition frequency, so high velocities can push the Doppler frequency beyond half of that sampling rate and wrap around. Continuous-wave Doppler, on the other hand, transmits and receives continuously along the entire beam path, so there’s no discrete sampling tied to a PRF. Because there isn’t a Nyquist limit being exceeded, aliasing cannot occur in CW Doppler. The trade-off is that CW lacks depth information, but aliasing isn’t a concern.

Aliasing in Doppler studies comes from sampling the signal at a finite rate. In pulsed Doppler, the signal is sampled at the pulse repetition frequency, so high velocities can push the Doppler frequency beyond half of that sampling rate and wrap around. Continuous-wave Doppler, on the other hand, transmits and receives continuously along the entire beam path, so there’s no discrete sampling tied to a PRF. Because there isn’t a Nyquist limit being exceeded, aliasing cannot occur in CW Doppler. The trade-off is that CW lacks depth information, but aliasing isn’t a concern.