CONTENTS Preface Introduction Finite Element Formulation Finite Element Mesh Truncation

Transcription

1 Preface xi 1 Introduction Numerical Simulation of Antennas Finite Element Analysis Versus Other Numerical Methods Frequency- Versus Time-Domain Simulations Brief Review of Past Work Overview of the Book 9 References 11 2 Finite Element Formulation Finite Element Formulation in the Frequency Domain Finite Element Formulation in the Time Domain Modeling of Complex Materials Modeling of Electrically and Magnetically Lossy Materials Modeling of Electrically Dispersive Materials Modeling of Magnetically Dispersive Materials Modeling of Doubly Dispersive Lossy Materials Validation Examples Solution of the Finite Element Equations Higher-Order and Curvilinear Finite Elements Summary 52 References 53 3 Finite Element Mesh Truncation Absorbing Boundary Conditions First-Order Absorbing Boundary Condition Second-Order Absorbing Boundary Condition Perfectly Matched Layers PML in Terms of Stretched Coordinates PML as an Anisotropic Material Absorber PML for Truncating the Computational Domain Finite Element Implementation of PML ABC-Backed, Complementary, CFS, and Second-Order PMLs 72 v

2 vi CONTENTS 3.3 Boundary Integral Equations Frequency-Domain Formulations Time-Domain Formulations Treatment of the Infinite Ground Plane Summary 96 References 97 4 Hybrid FETD FDTD Technique FDTD Method PML Implementation in FDTD FDTD Stretched-Coordinate PML FDTD Anisotropic-Medium PML Near-to-Far-Field Transformation in FDTD Alternative FETD Formulation Equivalence Between FETD and FDTD Stable FETD FDTD Interface Initial Approaches Stable Formulation Building Hybrid Meshes Wave-Equation Stabilization Validation Examples Summary 140 References Antenna Source Modeling and Parameter Calculation Antenna Feed Modeling Current Probe Voltage Gap Generator Waveguide Feed Model Plane-Wave Excitation Total-Field Formulation Scattered-Field Formulation Total- and Scattered-Field Decomposition Approach Far-Field Pattern Computation Near-Field Visualization Summary 182 References Modeling of Complex Structures Thin-Material Layers and Sheets Impedance Boundary Conditions Shell Element Formulation 197

3 vii 6.2 Thin Wires and Slots Thin Wires Thin Slots Lumped-Circuit Elements Coupled First-Order Equations Wave Equation Example Distributed Feed Network System-Level Coupling Example Internal Dispersive Material Calibration External Illumination and Aperture Coupling Summary 234 References Antenna Simulation Examples Narrowband Antennas Coaxial-Fed Monopole Antenna Monopole Antennas on a Plate Patch Antennas on a Plate Conformal Patch Antenna Array Broadband Antennas Ridged Horn Antenna Sinuous Antenna Logarithmic Spiral Antenna Inverted Conical Spiral Antenna Antipodal Vivaldi Antenna Vlasov Antenna Antenna RCS Simulations Microstrip Patch Antenna Standard Gain Horn Antenna Summary 262 References Axisymmetric Antenna Modeling Method of Analysis Finite Element Formulation Mesh Truncation Using Perfectly Matched Layers Mesh Truncation Using Boundary Integral Equations Far-Field Computation Application Examples Luneburg Lens Corrugated Horn Current Loop Inside a Radome Summary 282 References 282

4 viii CONTENTS 9 Infinite Phased-Array Modeling Frequency-Domain Modeling Periodic Boundary Conditions Mesh Truncation Techniques Extension to Skew Arrays Extension to Scattering Analysis Application Examples Time-Domain Modeling Transformed Field Variable Mesh Truncation Techniques General Material Modeling Application Examples Approximation to Finite Arrays Summary 332 References Finite Phased-Array Modeling Frequency-Domain Modeling FETI DPEM1 Formulation FETI DPEM2 Formulation Nonconforming Domain Decomposition Application Examples Time-Domain Modeling Dual-Field Domain-Decomposition Method Domain Decomposition for Iterative Solutions Application Examples Summary 382 References Antenna Platform Interaction Modeling Coupled Analysis FETI DPEM with Domain Decomposition Hybrid FETD FDTD with Domain Decomposition Hybrid FE BI Method with FMM Acceleration Decoupled Analysis Near-Field Calculation Far-Field Evaluation by Numerical Methods Far-Field Evaluation by Asymptotic Techniques Direct and Iterative Improvements Summary 417 References 418

5 ix 12 Numerical and Practical Considerations Choice of Simulation Technologies Frequency- Versus Time-Domain Simulation Tools Fast Frequency Sweep Numerical Convergence Domain Decomposition and Parallel Computing Verification and Validation of Predictions Summary 429 References 429 Index 431