Forward Scatter Radar Sensing in Virtual RF Fence Applications: Modeling and Functional Simulation

Abstract

Forward scatter radar (FSR) is a bistatic sensing technique used to detect and classify low-observable targets. It exploits the strong disturbance of the direct signal when a target crosses the transmitter–receiver baseline. Despite extensive research on FSR phenomenology, applications, and signal processing, the literature lacks a comprehensive end-to-end system-level simulator capable of modeling waveform generation, propagation, target scattering, and receiver processing simultaneously. This paper addresses this gap by presenting a unified MATLAB/Simulink-based framework for complete FSR system modeling and performance evaluation. The proposed model integrates the transmitter, antenna arrays, two-ray propagation channel, target kinematics, and receiver processing within a single simulation environment. A hybrid forward-scatter cross-section (FSCS) modeling approach is introduced, enabling the use of either analytical physical-optics-based formulations or full-wave electromagnetic simulations. The model is validated through comparisons with experimental measurements across diverse scenarios, including a metal plate at 5.46 GHz, a Land Rover–type vehicle at 175 MHz, and an inflatable boat at 7.5 GHz. In addition, representative maritime and space-based passive FSR scenarios are investigated to illustrate the impact of transmitter and receiver motion. The model enables efficient parametric studies, supporting practical FSR system design and optimization for security and surveillance applications.