A method is proposed to calibrate a planar phased array by reconstructing its aperture distribution, in which the aperture distribution is superposed within the physical range of radiating element. Consequently, the calibration coefficients are solved for the linear relationship between the superposed aperture distribution and elements' excitations. The calibration accuracy that is influenced by resolution of aperture distribution is also discussed in this paper. In practice, the reconstruction procedure of aperture distribution is based on the plane wave spectrum (PWS) theory, utilizing FFT and IFFT techniques. This method turns out to be valid by experiment.
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