Advanced Qualification · A-005 Transmitters, modulation and processing · A-005-009-006
Which type of signal is used to produce a predetermined alteration in the carrier for spread spectrum communication?
- A Quantizing noise
- B Random noise sequence
- C Pseudo-random sequence
- D Frequency-companded sequence
Correct answer: C — Pseudo-random sequence. From the official ISED question bank, verified word for word.
Why
A pseudo-random sequence is a specific pattern that looks random but repeats after a set time, allowing both the sender and receiver to synchronize and decode the spread spectrum signal correctly. 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.