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سؤال 485

What spread spectrum communications technique uses a high-speed binary bit stream to shift the phase of an RF carrier?

  1. Frequency hopping
  2. Direct sequenceپاسخ درست
  3. Binary phase-shift keying
  4. Phase compandored spread spectrum

توضیح

In direct sequence spread spectrum a fast pseudorandom bit stream, the chipping code, phase-modulates the carrier, so the occupied bandwidth is set by the chip rate rather than by the data rate. Frequency hopping spreads the signal by moving the carrier between channels instead, without phase shifting.

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شروع تمرین
سؤال 485: What spread spectrum communications technique uses a… · FCC Amateur Extra Class (Element 4) · Questena