Cassegrain Antenna - General Info

The application note provides essential information on this type of reflector antennas. WIPL-D MoM implementation is particularly well suited for reflector simulations, elaborated in detail (quadrilateral elements of 2λ × 2λ, up to the 8th expansion order, optimized for reflector performance). The approaches for building the model include specialized WIPL-D Pro geometrical objects, CAD file import, or user-defined script shapes, offering maximum flexibility. Simulation results for a 200λ Ka-band reflector demonstrate that very large reflector antennas can be efficiently simulated in WIPL-D software using a regular desktop PC, especially when equipped with low-end Nvidia GPU cards, ensuring fast, reliable analysis for complex structures.

View PDF

Parabolic Torus Reflector Antenna

WIPL-D Pro is a full-wave 3D EM solver based on MoM, ideal for radiating problems and electrically moderate to very large structures like reflector antennas. Key features include quadrilateral mesh, higher-order basis functions (HOBFs), efficient multi-core CPU parallelization, support for low-end GPU cards, and built-in pre-meshed reflector primitives for quick setup. Torus reflector antenna (TRA) rotates a parabola around a vertical axis, enabling efficient multi-beam operation, though with slightly lower aperture efficiency. Anti-symmetry reduces unknowns to less than 25,000. Reflector aperture is ~1.8×3 m (60×100 λ). Kernel runs twice on a desktop PC, with simulation times measured in minutes, further accelerated using GPU cards.

View PDF

Cassegrain Antennas with Diameters Up to 200 λ

Very large Cassegrain antennas are traditionally simulated using specialized asymptotic methods. However, WIPL-D Pro allows accurate and extremely fast simulation of these antennas using the Method-of-Moments with higher-order basis functions, achieving very high numerical efficiency. Thanks to efficient parallelization on modern multi-core computers, CPU simulations are fast even for large problems. Further acceleration is easily possible using the GPU Solver with inexpensive Nvidia GPU cards. This application note presents the number of unknowns and CPU/GPU simulation times for reflector sizes ranging from 20 to 200 wavelengths, demonstrating the capability of WIPL-D Pro to handle very large antenna structures efficiently and reliably.

View PDF

Splash Plate Reflector Antenna Design Guide

This note presents design of a splash plate reflector antenna, including theoretical considerations and foundations, as well as the complete design procedure in the WIPL-D software suite. The splash plate reflector antenna consists of two parts: a feeding cylindrical waveguide with a splash plate sub-reflector, and the main parabolic reflector. Accordingly, the design procedure is roughly divided into two steps corresponding to the design of each part, ensuring precise modeling and accurate results. Finally, the application note presents the WIPL-D Pro model at 25.5 GHz, its radiation pattern, and simulation details, carried out in seconds on an inexpensive PC, demonstrating efficiency and accuracy.

View PDF

Wire Reflectors

Simulation of reflector antennas can be very challenging for MoM codes. Despite this, WIPL-D Software, a MoM code based on SIE, proves to be a highly efficient and suitable tool for simulating large reflector antennas accurately. Reflectors, typically made of metallic surfaces, can also be modeled using relatively thin wires, either representing realistic reflectors or serving as wire grid approximations of solid reflectors. In this application note, both plate and wire reflectors illuminated by a choke horn are simulated, with results compared to demonstrate the efficiency of the wire grid model, highlighting required computational resources, reduced simulation time, and overall effectiveness in modeling complex reflector structures.

View PDF

Cassegrain Reflector Antenna Design Guide

This application note presents the procedure for design of a Cassegrain reflector antenna, including theoretical foundations and step-by-step design in the WIPL-D software suite. The antenna consists of two main parts: a feeding conical horn with hyperbolic sub-reflector, and a primary parabolic reflector. Accordingly, the design is divided into two stages. The application note also presents the WIPL-D Pro model at 25.5 GHz, including detailed radiation patterns and simulation results. All simulations are performed in seconds on an inexpensive everyday desktop PC, demonstrating both high accuracy and computational efficiency, making this approach suitable for practical engineering design and optimization of Cassegrain reflector antennas.

View PDF

Shroud Absorber & Radome Effects on Splash-Plate Reflector

WIPL-D Pro efficiently simulates electrically large reflector antennas, including splash plate reflectors with shroud, absorber, and radome, in dramatically low computational time on regular desktops or laptops. This application note presents a
35-lambda 16 GHz antenna, considering the feeder, splash plate, and dielectric support. The model is further enhanced by adding a metallic shroud, absorber, and a simple flat radome, showing significant improvement in front-to-back ratio, while the absorber causes minimal 0.8 dB gain reduction. All simulations are performed on a standard desktop equipped with a single low-cost GPU, transforming it into a high-performance workstation for fast, accurate analysis of complex reflector antenna designs.

View PDF

Analytical Feed for Illuminating Reflectors via Field Generators

This application note presents an efficient procedure for defining analytical feed in WIPL-D using the Field Generators feature as excitation for the EM problem. A reflector antenna with radius and focal distance of 10 wavelengths is used. For WIPL-D’s higher order basis functions and MoM, this is electrically small, allowing near-instant simulation on a standard laptop or desktop PC without requiring high-end hardware. Two approaches exist: tuning a rectangular horn or defining an analytical feed via Field Generators. Equations generate the pattern according to specifications. Results confirm Field Generators can successfully replace actual illuminators, especially when horn geometry is unknown or only measured pattern is available.

View PDF

Domain Decomposition Solver: Large Reflector Antennas

An electrically large Cassegrain reflector antenna was modeled using WIPL-D Pro and simulated using WIPL-D Pro with Domain Decomposition Solver (DDS). Radiation patterns were compared. The simulations were carried out using WIPL-D Pro, a full-wave 3D EM Method-of-Moments software which applies Surface Integral Equations and iterative DDS. Despite the large electrical size, results were obtained in relatively short time on a regular desktop PC with modern GPU cards. Convergence was excellent and consistent. Accuracy improved after each DDS iteration, and the third iteration matched the full 3D EM MoM result. All iterations completed in under 100 minutes, showing very high numerical efficiency even for a demanding 420-wavelength reflector.

View PDF

Domain Decomposition for Very Large Reflector Antennas

This application note expands on the previously published note Domain Decomposition Solver in Simulation of The Electrically Large Reflector Antenna. An electrically very large reflector antenna was simulated using WIPL-D Pro with Domain Decomposition Solver (DDS). The operating frequency was 25.5 GHz, and the result of interest was the radiation pattern in the phi=90° plane at 3601 equidistant directions along theta angle. All results were calculated quickly on an affordable desktop PC with GPU cards. Convergence was excellent, accuracy improved after the 2nd iteration, and further after the 3rd. All iterations completed in under 15 hours, showing very high numerical efficiency even for a reflector with diameter of 750 wavelengths.

View PDF