For a range of 10 nautical miles, what should the RADAR pulse repetition frequency (PRF) be?

The correct pulse repetition frequency (PRF) for radar systems is crucial for accurate target detection and tracking, especially at specific ranges. For a radar operating at a range of 10 nautical miles, it's essential to maintain a PRF that allows the radar to adequately receive and process reflected signals from targets at that distance.

A PRF of approximately 8.1 kHz or less is suitable because it ensures that the radar has sufficient time between transmissions to receive echoes from the furthest point, which in this case is 10 nautical miles. This frequency strikes a balance between detecting targets at longer ranges and minimizing the chances of experiencing range ambiguities.

In contrast, a PRF of 18.1 kHz or more would be inappropriate for this range, as such a high frequency could lead to range ambiguity, where signals from multiple pulses overlap and confuse target detection. Similarly, the other options either do not provide appropriate timing for the radar system or are defined in incompatible units for PRF. Thus, the correct choice optimally matches the operational needs of the radar system within the specified range.