Advanced Qualification · A-005 Transmitters, modulation and processing · A-005-009-002
What is the term used to describe a spread spectrum communications system where the centre frequency of a conventional carrier is changed many times per second in accordance with a pseudorandom list of channels?
- ADirect sequence
- BTime-domain frequency modulation
- CFrequency companded spread spectrum
- DFrequency hopping
Correct answer: D — Frequency hopping. From the official ISED question bank, verified word for word.
Why
Frequency hopping is the right term because it describes a system that rapidly jumps a carrier signal from one frequency to another according to a preset, random-looking pattern. The full explanation — and one for every question — is in Pro.
Practise this section
Transmitters, modulation and processing is section A-005 of the Advanced exam: Transmitters, modulation and processing: AM, FM, SSB, keying, speech processing, and the numbers behind occupied bandwidth.
Drill A-005 — free, no account