This NSF ERI project aims to uncover the effects of faults (i.e., short circuits) on High-Frequency (HF) carrier waves traveling through high-voltage Transmission Lines (TLs) to enable the development of source-independent protective devices (relays). Contemporary protection systems often fail to detect faults in grids dominated by Inverter-Based Resources (IBRs). This limits the capacity of electric grids to host large amounts of IBR-based generation units, urging the establishment of new fault detection methods. This research supports national priorities by: i) enhancing the reliability and resilience of the electric grid, ii) accelerating the integration of various energy resources, and iii) promoting energy security that promotes economic competitiveness. The intellectual merits of this project include: 1) advancing the fundamental understanding of wave propagation in flawed and inhomogeneous media (i.e., TLs), 2) discovering fault effects on carrier waves through deterministic mathematics, 3) determining and categorizing the effects of other disturbances (e.g., switching events) on carrier waves, and 4) establishing a foundation for creating innovative source-independent protection schemes premised on the fault effects on carrier waves. Since the proposed project will extend the understanding of wave propagation in inhomogeneous media, the results will serve as a knowledge source for others to build their research. The conclusions of the project will be transformative wi