Altair Feko 2021.2 User Guide

Key Features and Applications

Feko's versatility stems from its support for various solution methods and their hybridization, enabling efficient analysis across different model complexities and frequency ranges.

Feko Solution Methods:

• Full Wave Frequency Domain: MoM (Method of Moments), FEM (Finite Element Method), MLFMM (Multilevel Fast Multipole Method).
• Full Wave Time Domain: FDTD (Finite Difference Time Domain).
• Asymptotic Methods: PO (Physical Optics), LE-PO (Large Element Physical Optics), RL-GO (Ray Launching Geometrical Optics), UTD (Uniform Theory of Diffraction).

Primary Applications:

• Antenna Design: Analysis of various antenna types including wire, microstrip, horn, aperture, MIMO, reflector, phased arrays, and conformal antennas. Features include CMA for intelligent design and tools for windscreen antennas.
• Antenna Placement: Analyzing antenna performance influenced by platforms like aircraft, vehicles, and ships. MLFMM and asymptotic solvers are key for electrically large platforms.
• Radar Cross Section / Scattering: Calculating mono- and bi-static RCS for defense platforms, wind turbines, and automotive radar systems. High-frequency methods are used for electrically large platforms.
• Electromagnetic Compatibility (EMC) Analysis: Predicting emission and immunity performance, shielding effectiveness, noise coupling, RADHAZ, EMP, lightning, and HIRF analysis. Specialized cable modeling and solver tools are included.
• Waveguides: Simulation and optimization of waveguide components like filters and couplers using MoM and FEM.
• Radomes: Analysis of complex, multi-layer, and electrically large structures.
• Bio-Electromagnetics: Designing products and investigating safety for healthcare systems, including wireless bio-sensors and implanted devices.
• Microstrip Circuits: Design and analysis of filters, resonators, and passive components using optimized formulations for layered media.
• Special Materials: Modeling frequency selective surfaces (FSS), metamaterials, composites (e.g., carbon fiber), and anisotropic dielectrics.

CADFEKO - Preprocessing and Geometry Creation

CADFEKO is the graphical environment for creating and meshing geometry, defining solution settings, and requesting calculations. It allows for parametric model construction using primitive structures and Boolean operations.

• Interface Components: Quick Access Toolbar, Ribbon, Configuration List, Model Tree, Details Tree, Status Bar, Message Window, Notes View, 3D View, Search Bar, Application Launcher.
• Geometry Creation: Supports creating basic geometry (lines, polylines, splines, arcs, rectangles, polygons, ellipses, spheres, cylinders, cuboids, flares, cones) and complex geometry using Boolean operations (Union, Subtract From, Intersection, Split, Stitch) and extension operations (Spin, Loft, Sweep, Path Sweep).
• Transformations: Tools for translating, mirroring, rotating, scaling, aligning, and projecting geometry.
• Model Definitions: Setting model units, defining variables for parametric modeling, creating named points, defining workplanes, and setting model extents for accuracy control.
• Meshing: Generating triangular surface meshes or volume meshes (tetrahedra, voxels) based on solution methods. Includes tools for mesh repair and refinement.
• Validation: CEM Validate tool to check model integrity before simulation.

POSTFEKO - Post-processing and Results Analysis

POSTFEKO is used for visualizing and analyzing simulation results. It allows users to create graphs, 3D views, and reports.

• Interface Components: Quick Access Toolbar, Ribbon, Project Browser, Model Browser, Details Browser, Status Bar, 3D Views and Graphs, Result Palette, Search Bar, Application Launcher.
• Data Handling: Supports importing and exporting data in various file formats.
• Visualization: Creation of Cartesian, Polar, and Smith charts, as well as 3D views with cutplanes and legends. Features for animation and exporting images are available.
• Reporting: Tools for generating quick reports or custom reports using templates.
• Scripting: Lua scripting support for automating post-processing tasks.

EDITFEKO - Text-Based Input File Editor

EDITFEKO provides a text-based interface for creating and editing Feko input files (.pre). It offers a script editor with syntax highlighting, code completion, and debugging capabilities.

• PREFEKO Language: Concepts include comments, card formats, variables, labels, and conditional statements.
• Geometry Creation: Supports importing meshes and guidelines for mesh connectivity.
• Scripting: Advanced scripting features for controlling Feko simulations.

Feko Solution Methods and Optimization

Feko offers a wide array of solution methods suitable for different electromagnetic phenomena and scales. Optimization tools allow for design refinement.

• Solution Methods: Includes full-wave methods like MoM, FEM, MLFMM, FDTD, and asymptotic methods like PO, LE-PO, RL-GO, and UTD. Hybridization of these methods is a key strength.
• Optimization: Feko integrates optimization engines (e.g., genetic algorithm) and interfaces with Altair HyperStudy for design exploration, parameter optimization, and goal definition.

Feko Utilities

A suite of utilities supports the Feko workflow:

• PREFEKO: The preprocessor for creating input files.
• Solver: Runs sequential, parallel, or remote simulations.
• OPTFEKO: For optimization and sensitivity analysis.
• ADAPTFEKO: For adaptive sampling.
• Updater: Manages software updates.
• Crash Report Utility: Assists in diagnosing issues.
• QUEUEFEKO: For managing simulation jobs.

Output File Description

Feko generates various output files detailing geometric data, excitation, currents, charges, near/far fields, S-parameters, and computation time/memory usage.

Feko Application Macros

Macros automate repetitive tasks within CADFEKO and POSTFEKO, with a library of shared and component-specific macros available for common operations like antenna array generation or MIMO performance evaluation.

Appendices

The appendices provide supplementary information, including detailed EDITFEKO cards, how-to guides for specific tasks (e.g., meshing, feeding antennas, improving convergence), SAR standards, solution control, file format descriptions, integration with other tools, and a list of acronyms.