QAM

RU: QAM

Quadrature Amplitude Modulation: a digital modulation scheme that encodes data by varying both the amplitude and phase of a carrier, mapping groups of bits to points in a constellation diagram. 64-QAM encodes 6 bits per symbol, 256-QAM encodes 8 bits per symbol; higher orders pack more bits but require a cleaner signal and higher SNR to decode reliably.