Evaluation of Site Errors in LLS Magnetic Direction Finding Caused By Large Hills Using the 3D‐FDTD Technique

Angle and amplitude estimation errors in magnetic direction finding, called site errors, are important sensor-specific lightning location systems (LLS). They known to be caused by nearby cables overhead lines due induced currents. Due the reflection diffraction of electromagnetic waves, hills mountains also expected generate these effects. In this paper, numerical computations applying finite-difference time-domain (FDTD) method performed analyze impact or on angle LLS sensors for typical first subsequent return strokes (RS). The influence hill size, distance hill, ground parameters, sensor bandwidth, evaluated. results show that top low ridges only 125 m elevation, up ±10° error +50% occur. A key finding is field attenuation lossy bandwidth limitations, there practically no difference RS. For two sensors, average obtained from real measurements compared 3D-FDTD simulations, modeling terrain based a digital elevation model. simulation good agreement with observed, errors.