Principles and Implementation of Quadrature Amplitude Modulation (QAM) with Performance Analysis
This article discusses the principles and implementation of M-ary Quadrature Amplitude Modulation (MQAM) modulation and demodulation, performance comparisons between MQAM, OFDM, and MPSK, and MQAM performance in noisy channels along with improvement techniques such as channel coding and frequency-domain equalization. Simulation experiments are conducted on communication channels with known characteristics to verify MQAM feasibility and effectiveness. The implementation can be modeled using MATLAB's Communications Toolbox functions like qammod and qamdemod for modulation/demodulation operations, with error rate analysis performed through bertool for system validation.