Which term describes reducing the gain of selective IF amplifier stages for large target returns?

Which term describes reducing the gain of selective IF amplifier stages for large target returns?

• A. FTC
• B. COAC
• C. AGC
• D. Limiter

Answer: (B)

The idea being tested is how a radar receiver keeps strong echoes from overwhelming the IF stages. When a target returns a very large signal, you want the circuit to back off its gain so the later stages don’t saturate and distort the measurement. COAC describes this approach: reducing the gain specifically in the selective IF amplifier stages as the input grows. This keeps the output in a usable, roughly linear range, which helps preserve visibility of weak targets while preventing overload from strong ones. Think of it as a targeted automatic gain control for the IF path. It contrasts with a limiter, which would clip the signal and distort the waveform; with a broad automatic gain control that might reduce gain more globally; and with the fast/slow time constants, which merely describe how quickly the control responds rather than the fundamental action of lowering gain. By focusing the gain reduction on the IF stages, COAC provides a balanced way to handle wide variations in target strength.

The idea being tested is how a radar receiver keeps strong echoes from overwhelming the IF stages. When a target returns a very large signal, you want the circuit to back off its gain so the later stages don’t saturate and distort the measurement. COAC describes this approach: reducing the gain specifically in the selective IF amplifier stages as the input grows. This keeps the output in a usable, roughly linear range, which helps preserve visibility of weak targets while preventing overload from strong ones.

Think of it as a targeted automatic gain control for the IF path. It contrasts with a limiter, which would clip the signal and distort the waveform; with a broad automatic gain control that might reduce gain more globally; and with the fast/slow time constants, which merely describe how quickly the control responds rather than the fundamental action of lowering gain. By focusing the gain reduction on the IF stages, COAC provides a balanced way to handle wide variations in target strength.