Which parameter indicates how much a receiver degrades the signal quality, affecting sensitivity?

• A. Noise Figure
• B. Squelch Level
• C. Bandwidth
• D. Gain

Answer: (A)

The key idea is how much noise the receiver itself adds to the signal, which affects how weak a signal can be and still be detected. This is captured by the Noise Figure. It tells you how the input signal-to-noise ratio is degraded by the receiver: the higher the Noise Figure, the more the SNR is reduced, and the poorer the sensitivity. A low Noise Figure means the receiver preserves the input SNR better, giving better sensitivity.

Squelch level only sets the threshold at which audio is muted and does not describe how much noise the receiver introduces. Bandwidth defines the range of frequencies the receiver can process and how much noise is included across that range, but it doesn’t measure the receiver’s own added noise per se. Gain is about amplification of the signal (and noise) but doesn’t quantify the intrinsic degradation of signal quality inside the receiver.