Analysis and Optimization of Nonlinear Diode Grids for Shielding of Enclosures With Apertures

Lumped-element grids provide an attractive option for wave propagation control in electromagnetic compatibility (EMC) engineering. This article investigates the peak shielding effectiveness (SE) of a diode grid used for protection of enclosures with apertures against high-intensity radiation fields (HIRFs). The nonlinearly loaded aperture is investigated with an efficient hybrid field-circuit simulation approach. Numerical experiments show that design aspects, e.g., aperture and enclosure size, grid density, impedance characteristic of lumped loads, play an important role in the field transmission through a diode grid which is nonlinear and time-variant. With a physics-based analysis of the interaction between the grid and the enclosure-backed aperture, nonlinear shielding techniques are identified that allow a control of the peak SE between 0 and 26 dB in novel ways. For the first time, the peak SE curve of a diode grid is demonstrated with four different field intensity dependencies, i.e., intensity low-pass, intensity high-pass, intensity bandpass, and intensity band-stop selectivities from tens V/m to hundreds of V/m. By considering design aspects into a two-step optimization procedure, practical guidelines are provided for the nonlinear shielding implementation.

Subjects

Apertures

band-stop

Bandpass

Computational modeling

diode grids

field intensity selectivity

guideline

hybrid simulation

Integrated circuit modeling

Load modeling

nonlinear shielding

Optimization

Switches

Transient analysis

Options

Analysis and Optimization of Nonlinear Diode Grids for Shielding of Enclosures With Apertures