Extra exam question E8C13
Subelement E8, SIGNALS AND EMISSIONS· Group E8C
What is described by the constellation diagram of a QAM or QPSK signal?
- A.How many carriers may be present at the same time
- B.The possible phase and amplitude states for each symbol (correct answer)
- C.Frequency response of the signal stream
- D.The number of bits used for error correction in the protocol
WhyA constellation diagram of a QAM or QPSK signal describes the possible phase and amplitude states for each symbol. A constellation diagram plots the possible phase and amplitude states a QAM or QPSK signal's individual symbols can take, each point on the diagram representing one distinct combination of phase and amplitude that corresponds to a specific data value, answer B. It doesn't show how many carriers can be present simultaneously, doesn't depict frequency response, and doesn't indicate how many error-correction bits a protocol uses, those aren't what a constellation diagram is built to show.
Published 2026-08-28 · Last updated 2026-08-28 · Question text is verbatim from the 2024-2028 NCVEC Element 4 pool (public domain); the explanation above is original writing, see our methodology.
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