Doppler processing in radars benefits air defense by:

• A. It increases radar range by doubling power.
• B. It provides weather mapping.
• C. It measures a target's radial velocity to separate moving targets from stationary clutter and improve detection of fast-moving threats.
• D. It reduces the need for human involvement in target designation.

Answer: (C)

Doppler processing uses the Doppler shift to measure how fast something is moving toward or away from the radar along the line of sight. In air defense, this lets you separate moving targets from stationary clutter such as terrain, buildings, or weather returns. Stationary clutter shows little or no Doppler shift, while fast-moving threats produce a noticeable radial velocity. By isolating detections with real, significant velocity and suppressing near-zero-velocity clutter, the radar can detect, track, and respond to fast-moving objects more reliably and quickly.

Other options miss the core benefit: Doppler does not increase range by doubling power, and weather mapping, while possible with Doppler radars, is not the primary air defense advantage described here. automation or reduced human involvement can help, but the fundamental win is the ability to discriminate moving targets from clutter through velocity information.