MATLAB Implementation of PSK Modulation and Demodulation with Constellation Diagram Visualization

This article provides a detailed explanation of the PSK (Phase Shift Keying) modulation and demodulation process, along with comprehensive guidance for plotting constellation diagrams. Beyond introducing the "dmod" and "pskmod" MATLAB commands, we thoroughly examine their specific applications and parameter configurations. The dmod function serves as a general digital modulation tool requiring parameters like modulation type, sampling rate, and carrier frequency, while pskmod specifically handles PSK modulation with key parameters including modulation order (M), input symbols, and initial phase offset. Furthermore, we explore PSK modulation's applications in communication systems and conduct comparative analyses with other modulation techniques like FSK and QAM. From an implementation perspective, we discuss constellation diagram generation algorithms using MATLAB's scatterplot function, which visualizes complex signal points on the I-Q plane. Overall, PSK modulation and demodulation play crucial roles in digital communications, and by deeply understanding their underlying principles and practical implementations, we can better comprehend and apply these concepts in real-world scenarios.