Research on PPM Signal Demodulation Methods

This study provides a comprehensive investigation into Pulse Position Modulation (PPM) signal demodulation methods, encompassing two distinct demodulation programs: hard-decision and soft-decision approaches. In the hard-decision implementation, the program utilizes direct threshold-based decision criteria to determine signal states, typically involving amplitude comparison operations at specific sampling points. The soft-decision program employs more sophisticated algorithms, such as maximum likelihood estimation or probability-based decision metrics, to enhance demodulation accuracy by processing continuous signal values rather than binary decisions. Through comparative analysis of these demodulation methods, including performance evaluation of bit error rates and computational efficiency, we gain deeper insights into optimal PPM signal demodulation techniques for practical applications. The research includes MATLAB-based implementations demonstrating key functions like signal sampling, threshold calculation, and decision metric optimization for both approaches.