512-QAM - Computer Definition
A variation on the quadrature amplitude modulation (QAM) signal modulation scheme. 512-QAM yields 512 possible signal combinations, with each symbol representing nine bits (2 9 = 512). The yield of this complex modulation scheme is that the transmission rate is nine times the signaling rate. See also amplitude, bit, modulation, QAM, signal, signaling rate, symbol, and transmission rate.