ESTEAM: Accurate and efficient prediction of the full antenna system
An antenna never exists alone in the world, but is always, in practice, part of a system. The general nature of the full antenna system – consisting, for example, of the antenna mounted on a satellite platform – warrants a general RF analysis method to predict the so-called installed antenna performance. The Method of Moments (MoM) is a general method and the core of TICRA’s Electromagnetic Simulation Tool for Electrically large Antenna Models software – or simply the ESTEAM software.
TICRA acquired the MoM code that had been developed in a PhD project at DTU Elektro in 2003. In 2006, it was first released as the MoM add-on for the GRASP 9.3.01 release, allowing GRASP users to augment reflector antenna RF analyses with installed performance using full-wave MoM simulations.
The key ingredient of this code was, and continues to be, efficient higher-order basis functions on a higher-order quadrilateral mesh for representing the unknown currents. Put simply, this higher-order representation means that fewer unknowns can be used, without loss of accuracy, for representing the currents, prompting much smaller memory requirements and solution times.
To cater for general geometries, TICRA developed an in-house mesher specialized to the higher-order quadrilateral meshes. With the ability to import general, and thus also electrically very large platforms, an even more efficient approach was needed. Therefore, in a parallel PhD project between TICRA and DTU Compute, a version of the so-called Multi-Level Fast Multipole Method (MLFMM) relying on the higher-order basis functions was developed and validated. The MoM add-on was augmented with MLFMM in 2015 with the release of GRASP 10.4. With the GRASP 10.6 release in 2017 users could import CAD file geometries and perform MoM and MLFMM simulations directly on these.
In addition to electrically large platforms, TICRA’s MoM/MLFMM approach lends itself to simulating and designing general antennas, such as patch, microstrip and helix antennas, among many others. On this ground, the MoM add-on was in 2019, with the first release of TICRA Tools, turned into a standalone product, ESTEAM, which can be used independently of GRASP.
Today, ESTEAM is by far the most efficient and powerful full-wave RF simulation tool on the market for electrically large structures and platforms. It is used throughout the satellite industry for simulating large telecommunications satellites, in Ka band and beyond.
Fun fact: According to an engineer from NASA Jet Propulsion Laboratory, they barely need antenna measurements anymore, as a similar quality of antenna validation can be achieved with ESTEAM.