tailieunhanh - Báo cáo hóa học: " Research Article Joint Estimation of Mutual Coupling, Element Factor, and Phase Center in Antenna Arrays"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Joint Estimation of Mutual Coupling, Element Factor, and Phase Center in Antenna Arrays | Hindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking Volume 2007 Article ID 30684 9 pages doi 2007 30684 Research Article Joint Estimation of Mutual Coupling Element Factor and Phase Center in Antenna Arrays Marc Mowler 1 Bjorn Lindmark 1 ErikG. Larsson 1 2 and Bjorn Ottersten1 1 ACCESS Linnaeus Center School of Electrical Engineering Royal Institute of Technology KTH 100 44 Stockholm Sweden 2 Department of Electrical Engineering ISY Linkoping University 58183 Linkoping Sweden Received 17 November 2006 Revised 20 June 2007 Accepted 1 August 2007 Recommended by Robert W. Heath Jr. A novel method is proposed for estimation of the mutual coupling matrix of an antenna array. The method extends previous work by incorporating an unknown phase center and the element factor antenna radiation pattern in the model and treating them as nuisance parameters during the estimation of coupling. To facilitate this a parametrization of the element factor based on a truncated Fourier series is proposed. The performance of the proposed estimator is illustrated and compared to other methods using data from simulations and measurements respectively. The Cramer-Rao bound CRB for the estimation problem is derived and used to analyze how the required amount of measurement data increases when introducing additional degrees of freedom in the element factor model. We find that the penalty in SNR is dB when introducing a model with two degrees of freedom relative to having zero degrees of freedom. Finally the tradeoff between the number of degrees of freedom and the accuracy of the estimate is studied. A linear array is treated in more detail and the analysis provides a specific design tradeoff. Copyright 2007 Marc Mowler et al. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. 1. .