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سؤال 579

What is receiving directivity factor (RDF)?

  1. Forward gain compared to the gain in the reverse direction
  2. Relative directivity compared to isotropic
  3. Relative directivity compared to a dipole
  4. Peak antenna gain compared to average gain over the hemisphere around and above the antennaپاسخ درست

توضیح

Receiving directivity factor compares an antenna's peak gain with its average gain over the entire hemisphere around and above it. Since noise arrives from all of those directions, RDF predicts the signal-to-noise improvement a receiving antenna gives better than forward gain or front-to-back ratio do.

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شروع تمرین
سؤال 579: What is receiving directivity factor (RDF)? · FCC Amateur Extra Class (Element 4) · Questena