Numerical Simulation and Experimental Study of ISAR Imaging of Spherical Convergent Flap Nozzle

Authors

  • Yichao Liang School of Aerospace Engineering Xiamen University, Xiamen, Fujian 361005, China
  • Qingzhen Yang School of Power and Energy Northwestern Polytechnical University, Xi’an, Shaanxi 710072, China
  • Yongqiang Shi School of Power and Energy Northwestern Polytechnical University, Xi’an, Shaanxi 710072, China
  • Jin Bai School of Power and Energy Northwestern Polytechnical University, Xi’an, Shaanxi 710072, China
  • Qi Lin School of Aerospace Engineering Xiamen University, Xiamen, Fujian 361005, China

Keywords:

Inverse Synthetic Aperture Radar (ISAR), shooting and bouncing ray (SBR), scattering center, spherical convergence flap nozzle (SCFN)

Abstract

The research on the electromagnetic scattering characteristics of the aero-engine nozzle can provide an important reference for the electromagnetic stealth design of aircraft. In this paper, the numerical simulation and experimental measurement are used to study the radar cross section (RCS) and inverse synthetic aperture radar (ISAR) image characteristics of spherical convergence flap nozzle (SCFN). Firstly, the feasibility of using the shooting bouncing ray (SBR) method to calculate the scattering characteristics of electrically large and deep cavity is verified. Secondly, the numerical simulation data and experimental data of electromagnetic scattering of SCFN are processed by ISAR imaging algorithm, the numerical and experimental ISAR images of SCFN are obtained. The results show that SBR can effectively calculate the RCS of the electrically large size cavity within ± 30° of the axis direction. The polarization influences the experimental ISAR image. Both the numerical and the experimental ISAR image can accurately reflect the scattering center distribution inside the SCFN, and the numerical ISAR image is superior to the experimental ISAR image in image entropy and equivalent number of looks (ENL), and is partly inferior to the experimental ISAR image in terms of image average gradient. The results prove the validity and accuracy of the numerical ISAR image.

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How to Cite

[1]
Yichao Liang, Qingzhen Yang, Yongqiang Shi, Jin Bai, and Qi Lin, “Numerical Simulation and Experimental Study of ISAR Imaging of Spherical Convergent Flap Nozzle”, ACES Journal, vol. 35, no. 4, pp. 397–405, Apr. 2020.

Issue

2020: Vol 35 Iss 4

Section

Articles