This article presents a forward modeling method for the scattering center (SC) model of coated targets on rough ground, tailored for remote sensing and target recognition applications. The methodology initiates with the geometric model and coating impedance parameters of the ground target, employing a forward approach to decompose overall scattering into multiple component-level sources. Integrating high-frequency electromagnetic (EM) theory, quantitative computation, and derivation of SC parameters constructs a parameterized 3-D model for coated targets on rough ground. Illustrated through the example of a T72 tank and considering the effects of coated media and ground coupling, a forward SC model for the tank target on rough ground is developed. The model’s statistical characteristics are meticulously analyzed, and its accuracy is validated using real measurement data from publicly available datasets. The proposed model offers several advantages. First, it directly reflects the local geometry and coated material characteristics of target components, providing detailed information about component shapes and materials. Second, the modeling process meticulously considers and segregates the contributions of the target’s complex coupled SCs with the ground. A statistical analysis demonstrates consistent parameter convergence, aligning with theoretical expectations. Third, this research extends the forward modeling approach to coated targets on rough ground, enabling the model not only for component-level identification but also for rapid target synthetic aperture radar (SAR) echo reconstruction. In conclusion, this cost-effective approach provides a practical means for the rapid estimation and analysis of radar characteristics, target detection and recognition, target remote sensing, and other applications in complex environments.

In practical radar applications, the diversity of wideband transmission signals presents a significant challenge for radar target recognition systems. Traditional electromagnetic (EM) simulation methods often require the point-by-point sampling of target echo signals under specific radiation sources, and this process must be repeated for different transmission signals. This results in extensive EM computations and low computational efficiency. Additionally, the physical attribute information of the target is often obscured within the simulated echoes, complicating feature extraction. To address these issues, we propose a novel method for the efficient and rapid modeling and analysis of complex target time-domain echoes based on a forward scattering center model. This method constructs an impulse response model of the target under unit impulse signal excitation, representing the inherent scattering properties of the target and remaining unaffected by changes in the radiation source. Subsequently, this model is convolved with arbitrary wideband input signals to quickly reconstruct the wideband echo signals of the target. Numerical examples validate the accuracy and effectiveness of the proposed model. This method offers several advantages: firstly, it provides high computational efficiency by quickly convolving with the input signals, thereby avoiding the extensive EM calculations required by traditional methods due to changes in the radiation source. Secondly, it achieves significant data compression; the proposed echo model only requires the model parameters to be calculated at the central frequency point, enabling the rapid reconstruction of target echo data across a wideband range and effectively reducing storage requirements. Finally, it presents clear and complete physical attributes by employing a “cause-to-effect” forward-modeling approach, where the model parameters fully represent the inherent physical properties of the target. This effectively addresses the issue of physical interpretability in optical region radar target recognition.

An efficient method is proposed in this letter for analyzing electromagnetic scattering from complex targets coated with anisotropic metal composites. The method discretizes electromagnetic scattering on the complex target's surface into a superposition of triangular surface element scattering. Initially, the plane wave spectrum expansion method derives the dual spectral domain integral representation of the scattering from triangular surface elements on the anisotropic metal composites coated slab model. Then, the saddle point evaluation is utilized to perform the asymptotic evaluation of the integral, the reflection coefficient can be obtained in the spatial domain. Finally, the equivalent electromagnetic current of the triangular surface elements is solved using the Stratton-Chu equation. Furthermore, the electromagnetic scattering of complex targets coated with anisotropic metal composites is obtained through the physical optics (PO) method. The numerical results, including radar cross-section (RCS) comparisons for typical slab, cube, and fighter models, demonstrate the accuracy and efficiency of the proposed method. The anisotropic metal composites can enhance the stealth capability of the fighter, which possesses excellent structural stealth performance.

This paper presents a forward modeling method for the scattering center (SC) model of dynamic ships on time-varying sea surfaces, tailored for remote sensing and target-recognition applications. Grounded in ship hydrodynamics, the methodology delineates ship movements amidst fluctuating waves, harnessing computer graphics to integrate ship–sea geometries across diverse temporal instances. Utilizing the four-path model, the composite scattering effects are segregated into distinct ship and sea contributions, along with their mutual interactions. Augmented by high-frequency electromagnetic principles, the paper quantifies and deduces SC parameters, culminating in a 3-D parameterized SC model for complex maritime targets. Unlike conventional inverse methods, this approach employs a “cause-to-effect” forward strategy, establishing clear links between SCs and local geometries, enhancing the model’s physical clarity. Using the fishing ship as a case, this research compared the normalized similarity index and position-matching rate between the reconstructed synthetic aperture radar (SAR) image and the simulated SAR image. The results indicate that all computed results exceeded 90%. Furthermore, a comparison was conducted between the reconstructed radar cross-sections (RCS) obtained by expanding the model within a large angular range and the simulated results. The root mean square error between the two was less than 3 dB, affirming the accuracy and effectiveness of the proposed model. Additionally, the research examines the variations in SCs during the six-degrees-of-freedom motions, providing a detailed quantitative analysis of their temporal trends in amplitude and position. In summary, this investigation furnishes an efficient and economical framework for rapid radar characterization in dynamic, variable marine environments, fostering advancements in remote sensing and maritime target identification.

The paper presents a high-frequency modeling approach tailored for the electromagnetic (EM) scattering characteristics from electrically large radar targets coated with multi-layered anisotropic mediums (MLAMs). The approach begins by deriving the plane-wave spectrum expression for the incident EM field within MLAMs. It then employs spectral domain full-wave analysis method (SDFWAM) to obtain an analytical representation of the scattering field, further leveraging saddle point evaluation (SPE) to derive asymptotic solutions in the spatial domain. By integrating principles of physical optics (PO) and the tangent plane approximation, the far-field scattering characteristics of target enveloped in the specified medium are efficiently delineated. Validations against standard structure and the Misty satellite model reveal the method's pronounced alignment with the method of moments – finite element method (MoM-FEM) hybrid numerical algorithm, underscoring its notable computational efficiency. Furthermore, in conjunction with scattering sources decomposition technique, the approach is applied to optimize the radar cross-section (RCS) of the Su-57 aircraft, achieving precise and intelligent RCS control at minimal material cost. In conclusion, this research offers pivotal technological and theoretical foundations for EM scattering prediction, stealth design, and performance assessment in radar target domains.

To address the challenges posed by composite targets composed of an anisotropic medium and metal in electromagnetic (EM) scattering calculations, this paper introduces an innovative hybrid algorithm tailored for simulating the EM scattering characteristics of such complex targets. Utilizing impedance boundary condition (IBC), the method employs surface impedance vectors to precisely depict the EM properties of the medium. By harnessing the distinct advantages of the Method of Moments (MoMs) at low frequency and Physical Optics (POs) at high frequency, the algorithm ensures both accuracy and efficiency in the EM simulation of composite targets. By transforming the EM scattering problem of targets coated with a thin-layered medium into an equivalent radiation problem of EM currents on impedance surfaces, this research has achieved rapid and high-precision calculations of the Radar Cross Section (RCS) for complex targets with anisotropic medium coatings. To assess the performance of the algorithm, three target models—square plates, simplified aircraft, and complex satellites—are selected as test cases. The dual metrics of RCS and surface current distribution are utilized as evaluation benchmarks, and comparisons are made against the Method of Moments–Finite Element Method (MoM-FEM) hybrid numerical method. The comparative results demonstrate that the proposed method meets the engineering standards in terms of both the root mean square error (RMSE) of RCS and the relative error in surface current distribution, while also achieving a significant improvement of over 50% in computational efficiency, thereby validating its superior accuracy and practical utility.