Effective electric permittivity and magnetic permeability for metamaterial structures are extracted from 3D field simulation data. The equivalent representation of the metamaterial is a homogeneous slab described with parameterized dispersive Drude and Lorentz models. The parameters of dispersive models are obtained by optimization. Proposed approach is applied to the extraction of effective material parameters for double negative metamaterial cells. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 285–288, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22105

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This paper describes an experimental study of gamma radiation effects in low-density arrays of vertically aligned carbon nanotubes. These arrays are characterized by excellent anti-reflective and absorbing properties for wavelengths from UV to IR, which makes them an interesting option for stray light control in optical space applications. Gamma irradiation equivalent to an estimated surface lifetime exposition in geostationary orbit does not affect the reflectivity of the structures. First high-energy proton irradiation studies indicate that the reflectivity of the carbon nanotubes forests remains unchanged.

This paper presents the results of a test campaign meant to determine coupling paths into a laboratory test setup of typical power grid substation electronics. The devices were tested against conducted threats in a bulk current injection (BCI) setup and radiated threats inside a transverse electromagnetic (TEM) waveguide as well as with a near-field TEM horn antenna. The various excitation methods and different test setups offer the possibility to trace back the observed effects to coupling paths into the tested system. For frequencies below 300 MHz the dominating coupling path to the system under test (SUT) was determined to be the Ethernet cable connected to the telecontrol device. Above 800 MHz direct radiated coupling into the test devices was identified to be dominating. The conducted coupling via a predefined wiring harness with supply cabling was less relevant for both selected substation devices.