0-9 | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z
A carrier used to modulate another carrier. Note: The modulated carrier can be used to modulate another carrier, and so on, so that there can be several levels of subcarriers, i.e., several intermediate carriers. (188)