Receivers

What is the limiting condition for sensitivity in a communications receiver?

Answer

The noise floor of the receiver.

A receiver's ultimate sensitivity is set by its own internal noise floor; signals weaker than the noise cannot be recovered.

Source: FCC Element 3 question pool, 3F

Not the answer

  • The input impedance to the detector.
  • The power supply output ripple.
  • The two-tone intermodulation distortion.

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