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سؤال 109

What is the effect of antenna cross-polarization over a line-of-sight VHF or UHF path?

  1. Modulation sidebands might become inverted
  2. Received signal strength is reducedپاسخ درست
  3. Signals have an echo effect
  4. Nothing significant will happen

توضیح

Cross-polarization means the transmitting and receiving antennas are oriented at right angles, so the receiving element intercepts only a small part of the arriving field. Over a direct line-of-sight path there is no ionosphere to scramble the polarization, so the mismatch shows up as a large drop in received signal strength, often 20 dB or more.

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شروع تمرین
سؤال 109: What is the effect of antenna cross-polarization over a… · FCC Technician Class (Element 2) · Questena