Doppler spectra of electromagnetic wave scattered from an object flying above time-varying nonlinear sea surfaces

• Published in: Journal of electromagnetic waves and applications Vol. 33; no. 16; pp. 2175 - 2198
• Main Authors: Yang, Peng-Ju, Wu, Rui, Ren, Xin-Cheng, Zhang, Yu-Qiang, Zhao, Ye
• Format: Journal Article
• Language: English
• Published: Taylor & Francis 02.11.2019
• Subjects: Doppler spectrum; electromagnetic scattering; hybrid method; Kirchhoff approximation (KA); method of moments (MoM); nonlinear sea surface
• ISSN: 0920-5071; 1569-3937
• DOI: 10.1080/09205071.2019.1674191

Doppler spectra of electromagnetic wave scattered from an object flying above time-varying nonlinear sea surfaces are investigated by utilizing a hybrid algorithm combining method of moments (MoM) and Kirchhoff approximation (KA). The "choppy wave" model is employed for describing nonlinear hydrodynamic interactions between ocean waves. Doppler spectra of scattered wave are simulated and analyzed for different incidence angles, target velocities, target heights, sea states as well as sea surface models, and an obvious broadening of Doppler spectrum is observed due to the coupling scattering between the flying target and rough sea surfaces. In comparison with the normalized radar cross section, Doppler spectra of scattered wave have the advantage of extracting information regarding target flying above dynamic sea surfaces. This study is of great value for the analysis of coupling scattering between flying target and rough sea surface as well as for the detection low-flying target in sea clutter environment.