Karoo Array Telescope Berm Shielding: Efficient Computational Modeling and Multicopter Measurement
MetadataShow full item record
© 2016 IEEE. The square kilometer array is planned to be the most sensitive radio telescope of the 21st Century. Electromagnetic site quietness is a critical element in achieving the full science goals. We evaluate the shielding effectiveness of a soil berm at the South African Karoo site. The berm is electrically large and computationally expensive to model. A hybrid GO/MoM model using FEKO is proposed. Simulated data are compared to full-scale multicopter measurements. Broadband antennas are built into the landing structure and their patterns are deembedded during postprocessing. Simulations and measurements over 100-900 MHz (vertically polarized) show that the berm becomes effective from the point where its height reaches ten wavelengths. Shielding effectiveness values in the range of 25 dB are predicted by an approximate perfect electrical conductor ground model; the validity of this approximation is investigated. A simple knife-edge model is shown to provide a useful estimate of likely shielding. The results show that 3-D berm optimization using computational techniques is possible.
Showing items related by title, author, creator and subject.
Zhou, Y.; Wang, Y.; Ding, L.; Love, Peter (2018)© 2018 The shield method is a common approach used for subway tunnel excavation. A critical function of the shield method is the segment assembly process. It is, therefore, imperative to have access to information to be ...
Skinner, Geoff; Han, Song; Chang, Elizabeth (2006)There are numerous information privacy approaches based on the four major models of privacy protection. That is, Comprehensive Privacy Laws, Sectoral Privacy Laws, Privacy Self-Regulation, and Technologies of Privacy. ...
Skinner, Geoffrey; Chang, Elizabeth (2006)There are numerous information privacy approaches based on the four major models of privacy protection. That is, Comprehensive Privacy Laws, Sectoral Privacy Laws, Privacy Self-Regulation, and Technologies of Privacy. ...