Performance of bilinear time-frequency transforms in isar

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2007

Author

Loğoğlu, Berker

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In this thesis a stepped-frequency Inverse Synthetic Aperture Radar (ISAR) is employed to develop two-dimensional range-Doppler images of a small ghter aircraft which exhibits three dimensional rotational rotation. The simulation is designed such that the target can exhibit yaw, pitch and roll motions at the same time. First, radar returns from prominent scatterers of various parts of the target are processed and displayed using conventional Fourier transform. The e ects of di erent complex motion types and scenarios are observed and discussed. Then, several linear and bi-linear time-frequency distributions including shorttime Fourier transform, Wigner-Ville, pseudo Wigner-Ville, smoothed pseudo Wigner-Ville, Choi-Williams, Born-Jordan and Zhao-Atlas-Marks distributions are applied to the same target and scenarios. The performance of the transforms is compared for each scenario. The reasons for success of the distributions are discussed thoroughly.

Subject Keywords

Electrical engineering., Nuclear engineering.

URI

http://etd.lib.metu.edu.tr/upload/12609166/index.pdf
https://hdl.handle.net/11511/17309

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

B. Loğoğlu, “Performance of bilinear time-frequency transforms in isar,” M.S. - Master of Science, Middle East Technical University, 2007.