Field Interaction with Nonlinear Structures

Field Interaction with Nonlinear Structures

This project aims to contribute at the intersection of three different research areas:

  1. physics of electromagnetic field interaction with nonlinearly loaded, electrically large
    structures and surfaces,
  2. novel engineering applications for such structures and surfaces, and
  3. efficient and stable numerical modeling and simulation of such structures and surfaces.

While – at least in principle – any radio transmission system is an example for the application of electromagnetic field interaction with a nonlinearly loaded structure (antenna connected to input stage including e.g. mixer and amplifiers) and as such is well understood and can be designed readily with existing commercial software, it is the massive loading, i.e. the connection of several hundreds of nonlinear loads over an electrically large area, that has been of interest in the recent past and that poses new challenges and opportunities for research.Applications that are foreseen or already looked at for these kind of structures and surfaces include energy-selective shielding waveform-dependent absorption, self-focusing of surface waves, RF limiters, subwavelength imaging, nonlinear radar and switching, and time-domain windowing among others.

The research project is conducted in cooparation with Prof. Grivet-Talocia of the Department of Electronics and Telecommunications Politecnico di Torino (POLITO), Italy.The team of Prof. Grivet-Talocia has both expertise in fields of reduced-order macromodeling and fast circuit simulation, both of which are essential for this project. The EMC Group at POLITO is one of the major contributors in both theory and applications of behavioral macromodeling techniques for electrical and electromagnetic systems.Prof. Grivet-Talocia is co-Author of the first book on Passive Macromodeling [02], together with Dr. Gustavsen.Since 2001, Prof. Grivet-Talocia and his group developed tool IdEM, a collection of state-of-the-art algorithms for macromodel generation.


Picture

Illustration of energy selective (field strength) dependent protection of an electronic communication system inside a conducting casing. The rectangular aperture of the casing is covered by a conducting grid that is interspersed with diodes. Depending on the incident field strength and polarization the diodes are switched on, thus realizing the shielding effect of full metallic grid.Image taken from [01].


Picture

Hybrid simulation framework developed based on MoM for the electromagnetic part and a customized circuit solver for the nonlinear part. Image taken from [01].

Funding: DFG
Co-operation partner:
Department of Electronics and Telecommunications
Politecnico di Torino (POLITO)
Torino, Italy
Contact:Torben Wendt, M.Sc.

Sources:

[01] C. Yang, H.-D. Brüns, P. Liu, C. Schuster, “Impulse Response Optimization of Band-Limited Frequency Data for Hybrid Field-Circuit Simulation of Large-Scale Energy-Selective Diode Grids”, IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY, VOL. 58, NO. 4 (2016).

[02] S. Grivet-Talocia and B. Gustavsen, Passive Macromodeling: Theory and Applications. New York: John Wiley and Sons (2016).