What is used to determine the speed of a target in radar technology?

In radar technology, the speed of a target is primarily determined using the Doppler Shift. This phenomenon occurs when there is a change in frequency of the radar signal that is reflected off a moving object. As the target moves toward the radar source, the frequency of the returned signal increases; conversely, as it moves away, the frequency decreases. This change in frequency, or shift, can be measured and analyzed to calculate the velocity of the target accurately.

The Doppler Shift is crucial in applications such as law enforcement speed monitoring, weather radar, and military applications, where understanding the speed of an object is essential. It’s a foundational principle in modern radar systems, which makes it the correct answer to the question about determining a target's speed.

In contrast, options like Amplitude Modulation and Frequency Modulation pertain to how signals are modified for transmission but do not directly relate to speed measurement. Similarly, Pulse Width refers to the duration of a pulse in a radar signal but does not provide information about the speed of a target. Hence, the Doppler Shift is the optimal choice for understanding how radar systems determine target velocity.