Radar Echo Modeling and Mechanism Analysis of Ionospheric Clutter Based on Turbulence Dynamics

This study analyzes ionospheric turbulence mechanisms and their effects on high-frequency surface wave radar (HFSWR) systems, incorporating experimental validation.We develop an advanced radar echo simulation model using ionospheric turbulence principles and fluid dynamics. We employ Navier-Stokes and Reynolds-averaged Navier-Stokes (RANS) equations with the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">k − ε</i> model to simulate ionospheric inhomogeneities under various conditions. Our simulations examine laminar and turbulent flow states, revealing ionospheric irregularity formation and evolution. We identify five distinct types of ionospheric clutter: lamellar distribution, dot distribution, spatial correlation, distance-dependent, and target-like. We validate simulation results against 1290 range-doppler (RD) spectra from HFSWR measurements. This validation confirms the ability of the model to reproduce observed ionospheric phenomena and clutter patterns. Our findings offer insights into ionospheric layer interactions and their effects on radar signal propagation, advancing ionospheric clutter simulation and mitigation for HFSWR systems.