Question 8-5A4

Short-range RADARs prioritize precise range resolution and a high update rate. **Narrow pulses** are crucial for good range resolution. A shorter pulse duration allows the radar to distinguish between two targets that are close together in range, as the leading and trailing edges of the return pulse are clearer and less likely to overlap from closely spaced objects. **A fast rate (high Pulse Repetition Frequency - PRF)** is ideal for short-range applications because it allows for frequent updates. Since the signal travels a short distance, it returns quickly. A fast PRF ensures the next pulse is sent out soon after receiving the previous return, providing more samples per second and preventing "range ambiguity" where returns from a later pulse might be mistaken for returns from an earlier one at short distances. Conversely, wide pulses offer poor range resolution, and a slow pulse rate would result in infrequent updates, which is inefficient for short-range detection.