Conformal Array Geometry for Hemispherical Coverage

Conformal arrays may be a viable solution in many antenna applications requiring a wide angular coverage with sufficiently high directivity values, so it is worth comparing different 2D conformal array geometries to satisfy these requirements. To this end, first, the singular value decomposition (SVD) of the radiation operator is exploited to determine the maximum directivity values an array can reach in the whole observation domain. A numerical study based on the maximum directivity and, hence, on the SVD is then proposed to select the array geometry complying with some given requirements. Therefore, the performances achievable by some array geometries (a semi-circumference, a trapezoidal, and an angle array) are analyzed, and the one assuring a better hemispherical coverage is suggested. Furthermore, such an SVD-based study is usefully exploited to determine which panels of a multi-faceted array must be fed to reach some assigned specifications.

Synthesis of Angle Arrays by the NDF of the Radiation Integral

<div>This manuscript has been accepted for publication on IEEE Transactions on Antennas and Propagation.</div><div><br>Abstract:<br>The paper adopts an inverse problem approach to investigate the far zone radiation of a collection of 2D linear sources. By the evaluation of the number of independent pieces of information, i.e. the number of degrees of freedom (NDF), and the analysis of the reconstruction of a focusing beam, the role of the geometry can be examined in determining the set of possible radiation patterns. The results are relevant to the radiation pattern synthesis problem, since they allow to define the optimal source geometry for the hemispherical coverage with identical radiation patterns. </div>

Synthesis of Angle Arrays by the NDF of the Radiation Integral

<div>This manuscript has been accepted for publication on IEEE Transactions on Antennas and Propagation.</div><div><br>Abstract:<br>The paper adopts an inverse problem approach to investigate the far zone radiation of a collection of 2D linear sources. By the evaluation of the number of independent pieces of information, i.e. the number of degrees of freedom (NDF), and the analysis of the reconstruction of a focusing beam, the role of the geometry can be examined in determining the set of possible radiation patterns. The results are relevant to the radiation pattern synthesis problem, since they allow to define the optimal source geometry for the hemispherical coverage with identical radiation patterns. </div>

Occultation Judgment for the Hemispherical Coverage Multi-Planar Arrays Antenna

A flexible hemispherical coverage array antenna based on multi-planar arrays is proposed to meet the growing demands for multi-target TT&C. The advantages and disadvantages of multi-planar arrays and dome phased in engineering implement are compared. Meanwhile, the influence of different number of plane arrays on antenna pattern is analyzed. For the purpose of interference suppression a novel beamforming method by adding constraint conditions is analyzed to enhance the performance of antenna for TT&C system. Considering the influence of occultation effect on the antenna performance, an effective occultation algorithm is presented. Firstly, the faces in bright area are projected on the plane that is perpendicular with the direction of receiving wave. Secondly, adopting the principle of line segment intersection, the intersect relationship of projective planes is determined. Finally, the facets shadowing relationship is judged by the overlapping and depth-of-view of facets along the receiving wave direction. Theoretical analyses and simulation results show that the antenna has approximate uniform gain beampattern in different steered angle and the occultation algorithm is feasible and effective.