Title :
High-resolution radar in inhomogeneous media
Author :
Tanyer, S. Gökhun
Author_Institution :
Dept. Electr. & Electron. Eng., Baskent Univ., Ankara, Turkey
Abstract :
The problem of radar imaging in inhomogeneous media is considered. Electromagnetic fields are calculated by approximating the wave equation using the finite difference time domain (FDTD) technique. The variance in the permittivity of the medium is assumed be low-pass Gaussian. The received echoes are calculated for various values of surface roughness and permittivity differences. The effects of an aberrating layer on radar imaging are also examined. The cross-correlation between the echo signals received at different channels are calculated. The effects of inhomogeneity of the medium on the cross-correlation coefficients and on the point spread functions (PSF) are analyzed. The PSF corresponding to the delay-and-sum SAR algorithm and the delay-and-weighted-sum algorithm are compared
Keywords :
Gaussian distribution; approximation theory; correlation theory; electromagnetic fields; finite difference time-domain analysis; inhomogeneous media; optical transfer function; permittivity; radar imaging; radar resolution; rough surfaces; synthetic aperture radar; wave equations; FDTD technique; aberrating layer; cross-correlation coefficients; delay-and-sum SAR algorithm; delay-and-weighted-sum algorithm; echo signals; electromagnetic fields; finite difference time domain technique; high-resolution radar; inhomogeneous media; low-pass Gaussian variance; permittivity variance; point spread functions; radar imaging; surface roughness; wave equation approximation; Delay; Electromagnetic fields; Finite difference methods; Nonhomogeneous media; Partial differential equations; Permittivity; Radar imaging; Rough surfaces; Surface roughness; Time domain analysis;
Conference_Titel :
Signal Processing Proceedings, 1998. ICSP '98. 1998 Fourth International Conference on
Conference_Location :
Beijing
Print_ISBN :
0-7803-4325-5
DOI :
10.1109/ICOSP.1998.770231
