To overcome range ambiguity, the:

To overcome range ambiguity, it is crucial to understand the role of the pulse repetition frequency (PRF) in determining the maximum depth that can be accurately imaged. Range ambiguity occurs when ultrasound echoes from deeper structures return after the system has already started to receive echoes from shallower structures. This can create confusion in distinguishing the true location of the echoes.

By reducing the PRF, the time between consecutive pulses is increased, allowing for a clearer separation of echoes that return from different depths. A lower PRF means that the system has more time to receive reflected echoes from deeper tissues before it sends out the next pulse. This effectively enhances the ability to accurately capture and process the returning signals, thereby reducing the likelihood of confusing echoes from various depths.

In contrast, increasing the duty factor or imaging depth, or reducing the Reynolds number does not directly address the issue of range ambiguity. Increasing the duty factor might lead to more extensive overlap of echoes, while increasing the imaging depth can exacerbate range ambiguity if the PRF is not adjusted accordingly. The Reynolds number is a fluid dynamics parameter and does not pertain to the ultrasound imaging process in this context. Thus, reducing the PRF is the effective strategy for overcoming range ambiguity in imaging.