الفهرس 
Chapter 1: INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The performance of Ultra-Wide Band (UWB) radar in target detection, and recognition
depends on the structure of the radar waveform. A common waveform used in radar application is the
chirp waveform, which has a drawback of large time sidelobes (20dB). It also has an excessive range-
Doppler cross coupling results, when the Doppler shifted signal is correlated, and shows a different
time of arrival. In this thesis, a wide band chirp-Gaussian waveform with phase coding will be
proposed to overcome the drawbacks of the chirp waveform. The mathematical model,
autocorrelation function, power spectral density, and delay-Doppler Ambiguity Function (AF) for the
proposed waveform will be analyzed and plotted to illustrate its features for target detection, and
clutter suppression. This waveform may be a good choice for radar applications, like Synthetic
Aperture Radar (SAR) imaging to generate High-Resolution (HR) images.
The thesis explains a SAR simulator for the estimation of SAR images from the simulated raw
data using different waveforms such as random noise, chirp, and the proposed chirp-Gaussian
waveform with phase coding. Analogous to the conventional Gaussian signal, the chirp-Gaussian
waveform with phase coding that is composed of a large number of impulses provides the radiation
energy needed for improved target detection and the ultrawide bandwidth required for achieving HR
and reduced range estimation ambiguity.
The thesis also proposes a Range-Doppler Algorithm based on Fractional Fourier Transform
(RDA-FrFT) to obtain HR images for targets in radar imaging. The performance of the proposed
RDA-FrFT is compared with the classical Range-Doppler Algorithm (RDA), which is based on the
Fourier Transform (FT). Closed-form expressions for the range and azimuth compression of the
RDA-FrFT will be mathematically derived and analyzed. The RDA-FrFT offers better focusing
capabilities and greater side-lobe reduction ratios. The resolution of a point target with the proposed
RDA-FrFT is better than that with the classical RDA. The reflectivity profile obtained with the RDAFrFT
demonstrates a superior Signal-to-Noise Ratio (SNR) performance. Results show that the RDAFrFT
gives low Peak Side-Lobe (PSL) and Integrated Side-Lobe (ISL) levels after range and azimuth
compression for detected targets.
This thesis also studies the channel effect on SAR imaging. To reduce the channel effect, we
introduce three deconvolution methods; inverse filter, Linear Minimum Mean Square Error
(LMMSE), and regularized deconvolution. The mathematical form and implementation for the three
methods will be presented.