What does pulse width refer to?

• A. The length of time the transmitter is on for each transmitted pulse
• B. The frequency of the transmitted signal
• C. The time between transmitted pulses
• D. The width of the antenna beam

Answer: (A)

Pulse width is the duration that the transmitter is on during each radar pulse—the length of time the RF energy is emitted in a single burst. It's usually measured in microseconds. This duration determines how much energy is sent per pulse, which affects detection range, and it also sets the range resolution: longer pulses carry more energy but blur targets that are close together, while shorter pulses offer better range resolution but less energy per pulse. A useful relation is that range resolution is roughly the speed of light times the pulse width divided by two.

Pulse width is not the frequency of the signal, nor the time between pulses (that spacing is the pulse repetition interval), and it’s not the physical width of the antenna beam.