Modulation and Demodulation Schemes with MATLAB Implementation

This documentation provides MATLAB implementation code for several modulation and demodulation schemes, including Amplitude Shift Keying (ASK), Binary Phase Shift Keying (BPSK), Frequency Shift Keying (FSK), and Quadrature Amplitude Modulation (QAM). The source code offers significant value for communication researchers by demonstrating practical implementation techniques. Each scheme includes complete MATLAB functions with parameter configuration, signal generation, modulation/demodulation algorithms, and error analysis capabilities. The ASK implementation features envelope detection methods, BPSK code demonstrates coherent detection with carrier recovery, FSK includes non-coherent and coherent detection variants, while QAM implements constellation mapping and demapping with optimal decision regions. These codes not only provide working examples but also help researchers understand fundamental concepts like symbol mapping, pulse shaping, matched filtering, and bit error rate performance analysis. The implementations are structured to allow easy modification of parameters such as carrier frequency, sampling rate, and signal-to-noise ratio for performance testing. Researchers can leverage these codes for communication system design, algorithm verification, and educational purposes in digital communication studies.