Which change can be made in order to avoid exceeding the Nyquist limit?

Which change can be made in order to avoid exceeding the Nyquist limit?
A . Increase output power
B . Decrease output power
C . Increase pulse repetition frequency
D . Decrease pulse repetition frequency

View Answer

Answer: C

Explanation:

To avoid exceeding the Nyquist limit and prevent aliasing in Doppler ultrasound, the pulse repetition frequency (PRF) should be increased. The Nyquist limit is half of the PRF, so by increasing the PRF, the Nyquist limit is raised, allowing the system to accurately measure higher velocities without encountering aliasing artifacts.

Reference: ARDMS Sonography Principles and Instrumentation guidelines Zwiebel, W. J., & Pellerito, J. S. (2017). Introduction to Vascular Ultrasonography. Elsevier.