The advancement of power electronics has driventhe need for materials with superior electrical properties, leading to the use of wide band gap (WBG) semiconductors such as Silicon Carbide (SiC) and Gallium Nitride (GaN). These materialsexhibit higher breakdown voltages, faster switching frequencies, and better thermal stability compared to conventional silicon-based devices [1], [2], [3]. However, these benefits introducesignificant challenges in electromagnetic noise (EM noise) management, particularly due to rapid transitions characterized by high rates of change in voltage (dV /dt) and current (dI/dt)[4], [5]. This paper analytically investigates the sources and propagation of EM noise in high-frequency switching power modules using WBG semiconductors. Mathematical models are derived to describe the noise generated, incorporating factors such as parasitic inductances (L)and capacitances (C), frequency-dependent impedance (Z(f)), and noise power density (N(f)) [6]. The relationships between switching characteristics and noise amplitude are exploredthrough differential equations and Fourier analysis to map time-domain signals to their frequency components. Solutions for noise suppression are proposed, involving optimized circuit design and theoretical applications of electromagnetic wave propagation (EWP) principles, such as wave reflection and transmission in multi-layer structures [7], [8]. This work bridges theoretical electromagnetics with practical power module design, offeringstrategies that align with electromagnetic compatibility (EMC) standards and enhance performance.