Full exploitation of wavelet coefficients in radar imaging for improving the detection of a class of sources in the context of real data

M. Tria (1) , Jean-Philippe Ovarlez (2, 1) , L. Vignaud (1) , J.C. Castelli (1) , M. Benidir

1 ONERA - The French Aerospace Lab [Châtillon]
2 SONDRA - Sondra, CentraleSupélec, Université Paris-Saclay

As a time-frequency tool, the Continuous Wavelet Transform (CWT) was applied in radar imaging to reveal that the reflectors' response varies as a function of frequency f and aspect angle θ (orientation of the wave vector). To do so, we constructed a hyperimage expressed as the squared modulus of the wavelet coefficients, allowing to access to the energy distribution of each reflector, in the f − θ plane. Exploiting the hyperimage, our recent researches were devoted to the classification of the reflectors in function of theirs energy distributions with the objective of discriminating a type of target in the radar image. Althought acceptable results were obtained, the method is not reliable in some cases. The purpose of this paper is to show that exploiting not only the modulus but also the argument of the wavelet coefficients, can improve the detection of a certain class of reflectors. Results are presented at the end of this article.

Mots clés: Time-Frequency Analysis; Continuous Wavelet Transform; Nonstationary Signal; Radar Imaging; Detection; Source Classification; Target Extraction

Domaines: Traitement du signal et de l'image [eess.SP]

M. Tria, Jean-Philippe Ovarlez, L. Vignaud, J.C. Castelli, M. Benidir. Full exploitation of wavelet coefficients in radar imaging for improving the detection of a class of sources in the context of real data. 2006 14th European Signal Processing Conference, Sep 2006, Florence, Italy. ⟨hal-03152693⟩