Quadrature Amplitude Modulation

Quadrature Amplitude Modulation (QAM) is a modulation scheme used in digital communication systems to transmit data over radio waves or optical fibers. It is a combination of amplitude modulation and phase shift keying, where two carriers are modulated with the same amplitude but with a 90-degree phase shift. The resulting signal is a two-dimensional signal constellation, where each point represents a unique combination of amplitude and phase. QAM is used in many communication systems, including satellite communication, cable modems, and digital television. The number of points in the constellation determines the number of bits that can be transmitted per symbol. Higher order QAM schemes, such as 256-QAM or 1024-QAM, can transmit more bits per symbol but are more susceptible to noise and interference.
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