Advanced Qualification · A-005 Transmitters, modulation and processing · A-005-009-008
What is frequency hopping spread spectrum?
- A The carrier frequency is changed in accordance with a pseudo-random list of channels
- B The carrier is amplitude-modulated over wide range called the spread
- C The carrier is frequency-companded
- D The carrier is phase-shifted by a fast binary bit stream
Correct answer: A — The carrier frequency is changed in accordance with a pseudo-random list of channels. From the official ISED question bank, verified word for word.
Why
Frequency hopping spread spectrum works by rapidly moving the radio signal across different frequencies according to a secret, random pattern known only to the sender and receiver. The full explanation — and one for every question — is in Pro.
Practise this section
Transmitters, modulation and processing: AM, FM, SSB, keying, speech processing, and the numbers behind occupied bandwidth.