Efficient Prediction of Array Element Patterns Using Physics-Based Expansions and a Single Far-Field Measurement

• Published in: IEEE transactions on antennas and propagation Vol. 60; no. 8; pp. 3614 - 3621
• Main Authors: Maaskant, R., Ivashina, M. V., Wijnholds, S. J., Warnick, K. F.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.08.2012; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Antenna arrays; Antenna measurements; Antennas; Applied sciences; Arrays; Basis functions; Beam calibration; Beams (radiation); Calibration; Computer simulation; Covariance matrix; Exact sciences and technology; far-field pattern; Mathematical model; Mathematical models; phased array antennas; Radiocommunications; Reference sources; self-calibration; Studies; Telecommunications; Telecommunications and information theory; Voltage measurement; phased array antennas; Visual field; Multibeam antenna; Far field; Calibration; Phased array antenna; Modeling; Characteristic function; Interpolation; Beam calibration; far-field pattern; Basis function; Numerical simulation; Radiation pattern; Signal analysis; Antenna array; Analytical function
• ISSN: 0018-926X; 1558-2221; 1558-2221
• DOI: 10.1109/TAP.2012.2201104

A method is proposed to predict the antenna array beam through employing a relatively small set of physics-based basis functions-called characteristic basis function patterns (CBFPs)-for modeling the embedded element patterns. The primary CBFP can be measured or extracted from numerical simulations, while additional (secondary) CBFPs are derived from the primary one. Furthermore, each numerically generated CBFP, which is typically simulated/measured for discrete directions only, can in turn be approximated by analytical basis functions with fixed expansion coefficients to evaluate the resulting array pattern at any angle through interpolation. This hierarchical basis reduces the number of unknown expansion coefficients significantly. Accordingly, the CBFP expansion coefficients can be determined through a single far-field measurement of only a few reference sources in the field of view. This is particularly important for multibeam array applications where only a limited number of reference sources are available for predicting the beam shape. Furthermore, this instantaneous beam calibration is fast, i.e., potentially capable to speed up the array calibration by one or two orders of magnitude, which is particularly important if the antenna radiation characteristics are subject to drifts.