Geometric Space Optimization Based on Intelligent Algorithm for Tri-Reflector Compact Antenna Test Range

In the design process of the traditional compact antenna test range (CATR) system, the designer mainly considers electromagnetic characteristics, such as co-polar amplitude (phase) ripple, cross-polarization isolation, quiet zone (QZ) usage ratio, and bandwidth of the system. However, for CATR in the form of a multi-reflector or large aperture, the size of geometric space is an optimization metric that needs attention. In this communication, the proposed method combines the intelligent optimization algorithm with the B-spline surface-shaped algorithm closely, which allows the design of tri-reflector CATR with arbitrary aperture, and satisfactory results are achieved for electromagnetic characteristics and geometric space. The former optimizes the size of geometric space, and the latter generates the two shaped sub-reflectors under the condition that the geometric space reaches the global optimum. Finally, the designed tri-reflector CATR is simulated by physical optics (PO) and physical theory of diffraction (PTD) in GRASP10. Two numerical examples verify the effectiveness of the method.