Design and Implementation of a Wideband Flat Lens in Near Field RADAR Cross Section Reconstruction

Document Type : Original Article

Authors

1 Master's student, Faculty of Electrical Engineering, University of Tehran, Iran

2 Professor, Faculty of Electrical Engineering, University of Tehran, Iran

Abstract

Estimating RCS by near field methods has achieved great significance because of noticeable cost reductions. In this research we pursue RCS reconstruction by near field imaging with small processing load in laboratory conditions. A 10×10 cm meta surface lens in the 10-12 GHz frequency is designed and simulated for estimation of RCS, using near field imaging method which obtains the aperture efficiency and -1dB bandwidth of 32% and 7% respectively. This microwave lens is able to reduce the beam width by half. In this method, we ignore the image reconstruction step and use the obtained fields directly on a plane to estimate the RCS, causing a reduction in the volume of processing. The results show improvement in the estimated RCS, in addition to reducing the experiment distance, thus ensuring the possibility of implementation in the laboratory.

Keywords


[1]          C. Larsson, “Nearfield RCS Measurements of Full Scale Targets Using ISAR,” 2014.
[2]          D. M. Sheen, D. L. Mcmakin, and T. E. Hall, “Near Field Imaging at Microwave and Millimeter Wave Frequencies,” pp. 0–3, 2007.
[3]          A. Broquetas, L. Jofre, and A. Cardama, “Spherical Wave Near-Field Imaging and Radar Cross-Section Measurement,” vol. 46, no. 5, pp. 730–735, 1998.
[4]          D. Hristo and A. J. Herben, “Millimeter- Wave Fresnel-Zone Plate Lens and Antenna,” vol. 43, no. 12, 1995.
[5]          N. Gagnon, A. Petosa, and D. A. Mcnamara, “Thin microwave phase-shifting surface lens antenna made of square elements,” vol. 46, no. 5, pp. 9–11, 2010.
[6]          L. C. Gunderson and G. T. Holmes, “Microwave Luneburg Lens,” no. 5, pp. 801–804, 1967.
[7]          H. Chen, “A review of metasurfaces : Physics and tions,” no. May 2016.
[8]          M. R. Chaharmir, S. Member, J. Shaker, and S. Member, “Broadband Transmitarray Antenna Design Using Polarization-Insensitive Frequency Selective Surfaces,” no. c, 2015.
[9]          A. H. Abdelrahman, S. Member, A. Z. Elsherbeni, F. Yang, and S. Member, “Transmission Phase Limit of Multilayer Frequency-Selective Surfaces for Transmitarray Designs,” vol. 62, no. 2, pp. 690–697, 2014.
[10]        C. G. M. Ryan et al., “A Wideband Transmitarray Using Dual-Resonant Double Square Rings,” vol. 58, no. 5, pp. 1486–1493, 2010.
[11]        A. H. Abdelrahman, A. Z. Elsherbeni, F. Yang, and A. U. C. Element, “High-Gain and Broadband Transmitarray Antenna Using Triple-Layer Spiral Dipole Elements,” vol. 13, pp. 1288–1291, 2014.
[12]        H. Li, G. Wang, H. Xu, and T. Cai, “X-Band Phase-Gradient Metasurface for High-Gain Lens Antenna Application,” no. c, 2015.
[13]        L. Huang et al., “Bi-Layer Metasurfaces for Dual and Broadband Optical Antireflection,” 2017.
[14]        E. F. Knott, J. F. Shaeffer, and M. T. Tuley, Radar Cross Section Second Edition.