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David R. Novotny, Robert T. Johnk, Arthur Ondrejka
Abstract
We present and analyze a method for free-field evaluation of broadband absorber in a non-ideal testing environment. Using broadband, short-impulse TEM horns, a frequency-rich spectrum (equivalent pulse length < 0.5 ns) illuminates a sample of the material under test and the reflections are recorded. Unwanted reflections from the sample edges, room environment, antenna and other systematic events are mathematically removed by a combination of time gating, background subtraction and systematic de-convolution. The result is an estimate of the reflection characteristics of the center at the sample. We also present an uncertainty analysis of the measurement technique.
Novotny, D.
, Johnk, R.
and Ondrejka, A.
(2001),
Analyzing Broadband Free-Field, Absorber Measurements, Proc., IEEE Intl. Electromagnetic Compatibility (EMC) Symposium, Montreal, 1, CA
(Accessed October 10, 2025)