On the Numerical Modeling of Tapered Anechoic Ranges

Since their introduction in the late 1960s Tapered Anechoic Chambers have become popular tools for the measurement of antenna patterns at frequencies under 1 GHz. Since their inception several papers mention the fact that these chambers did not have a spherical wave propagation and thus, the Friis transmission equation to measure gain cannot be applied. This knowledge was presented in 1967 by King et al. and was based on measurements performed at X-band inside a scaled tapered anechoic range. In this paper numerical methods are applied to confirm the findings of the 1960s paper using different models of tapered ranges at different frequencies. While the results confirm the findings of the 1960s paper, they also validate some of the theories about the operation of these antenna ranges.