Which receiver function is responsible for decreasing the difference between the smallest and largest received amplitudes?

• A. Amplification
• B. Compensation
• C. Compression
• D. Demodulation

Answer: (C)

Dynamic range control in a receiver is about keeping signal levels within a usable band, so the widest swings in amplitude don’t overwhelm the system. Compression achieves this by reducing the gain more for larger signals and/or increasing gain for smaller ones, which brings the smallest and largest amplitudes closer together. This prevents strong signals from saturating the later stages and helps maintain a consistent level for weak signals, improving overall detectability and fidelity.

Amplification would push louder parts higher, widening the range rather than narrowing it. Compensation typically refers to correcting losses or shaping frequency response, not actively leveling amplitude. Demodulation recovers the information content and doesn’t by itself adjust the dynamic range across received amplitudes.