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Aiming at meeting the requirement of the amass high-quality SAR images needed by template-based ground target recognition engineering practice, a novel efficient SAR signal level simulation method is proposed. The electromagnetic scattering interaction mechanisms including coherent clutter of ground, multiple reflection and edge diffraction of vehicle, coupling-scattering between vehicle and ground are accurately estimated by utilizing an efficient ray-tracing technique. High quality SAR images are finally created through the SAR imaging procedure. Simulation results show that, the new method is feasible and effective.

The Equivalent Plane Model (EPM) and Phase Correction Algorithm (PCA) that are based on Transmission Line Theory (TLT) are proposed to satisfy the resource and efficiency requirements of ElectroMagnetic (EM) scattering analysis of large and complex multilayered dielectric targets. The proposed method accurately predicts the EM scattering characteristics of reference targets. To simplify the analysis, the multilayered dielectric slab structure is considered planar. On the basis of the TLT, the reflection and transmission coefficients of the plane are determined by using network analysis methods typically adopted in circuit analysis. Moreover, the reflection and transmission phases are corrected by considering the thickness of the multilayered dielectric slab and the direction of incidence and observation. Simulation results verify the applicability of the proposed method.

Based on ElectroMagnetic (EM) theory and the monopulse radar angle measurement principle, the formulae of angular glint for complex target are proposed and generally applied to tackling practical problems. The inherent relations among the three representations of radar angular glint, i.e. the phase-front distortion concept, the energy-flow tilt concept, and the monopulse radar angular noise concept, are clearly demonstrated. The two existing concepts of angular glint are also revised. Thus, a firm theoretical foundation for understanding, modeling, simulating and suppressing the angular glint from complex radar targets is established.

To simulate dynamic Radar Cross Section (RCS) of missile target group, an efficient RCS prediction approach is proposed based on the high-frequency asymptotic theory. The minimal energy trajectory and coordinate transformation is used to get trajectories of the missile, decoys and roll booster, and establish the dynamic scene for the separate procedure of the target group, and the dynamic RCS including specular reflection, edge diffraction and multi-reflection from the target group are obtained by Physical Optics (PO), Equivalent Edge Currents (EEC) and Shooting-and-Bouncing Ray (SBR) methods. Compared with the dynamic RCS result with the common interpolation method, the proposed method is consistent with the common method when the targets in the scene are far away from each other and each target is not sheltered by others in the incident direction. When the target group is densely distributed and the shelter effect can not be neglected, the interpolation method is extremely difficult to realize, whereas the proposed method is successful.

Traditional hidden surface removal algorithm based on hardware Z-Buffer technique cannot give attention to precision or efficiency at the same time when dealing with the non-uniform triangulated SAR scene model. A novel high-precision hidden surface removal approach using fast ray-tube splitting algorithm is proposed, where the SAR scene hidden surface removal problem is decomposed into two simple procedures, i.e. a Delaunay triangulator is used to generate the initial ray tubes from the projected point clouds of all incident visible vertices, then an adaptive ray-tube splitting method is adopted to carry out the complex scene shading situations and resultant visible model reconstruction. Simulation results of typical aircraft and T-72 tank show that, the new approach is feasible and effective.

Two concepts of angular glint are explained as well as the computation methods. A representative target consisting of two combined electric and magnetic dipoles with arbitrary orientation is presented In formulate angular glint linear deviations when the polarizations of the scattered waves and the receiving antenna are considered. Analysis shows that the equivalence between phase gradient method and Poynting vector method exists when geometrical optics approximation is used and the receiving antenna is linearly polarized.

The mode‐conversion coefficient is studied to investigate the ELF wave propagation over a mixed land‐to‐sea path. As partition by the consideration of reflection influence from the ionosphere layer, we assume the propagation can be regarded as being subjected to two different models over mixed paths, in terms of the propagation distance in the range of ELF far‐field and near‐field regions, respectively. Both of the mentioned stratified models can be represented as cascaded transmission networks at the abrupt junctions. In conformity with previous study to formulate the far‐field propagation as a cascaded terrestrial waveguide with abrupt height and ground impedance changes, the presented study proposed an equivalent cascaded network to exploit the concept of mode‐conversion for near‐field propagation across discontinuity. Representative parameters of ground types in contrast are supportive to demonstrate the interference of abrupt impedance‐change at ELF band. The presented analysis provide with computational schemes to obtain synthetic fields of ELF wave propagation, which could be extended to more realistic model over multi‐segmental mixed paths. [ABSTRACT FROM AUTHOR]