An improved near-field measurement method and near-far field transformation for cylindrical conformal phased array antenna

Near-field measurement has more advantages than conventional far-field measurement in determination of the antenna characteristics. An improved near-field measurement method and near-far field transformation for radar cylindrical conformal array antenna is presented in this paper, in order to meet the requirements, such as wide near field scanning range, high precision of near-far field transformation, fast testing efficiency and so on. Near-filed data including amplitude and phase is measured automatically by a cylindrical scan measurement system. Considering shielding effect of cylinder, near-far field transformation which is the most important part of near-field measurement has been proposed and based on Kirchhoff integral. Calculating far-field pattern utilizes near-field data in both polarizations, vertical and horizontal, and 3D far-field pattern of radar cylindrical conformal phased array antenna is obtained finally, the characteristics of antenna are displayed and analyzed conveniently. It is shown that this method is faster and more efficient than traditional method.