Spatially variant apodization for squinted synthetic aperture radar images.
Spatially variant apodization (SVA) is a nonlinear sidelobe reduction technique that improves sidelobe level and preserves resolution at the same time. This method implements a bidimensional finite impulse response filter with adaptive taps depending on image information. Some papers that have been previously published analyze SVA at the Nyquist rate or at higher rates focused on strip synthetic aperture radar (SAR). This paper shows that traditional SVA techniques are useless when the sensor operates with a squint angle. The reasons for this behaviour are analyzed, and a new implementation that largely improves the results is presented. The algorithm is applied to simulated SAR images in order to demonstrate the good quality achieved along with efficient computation.
Castillo-Rubio
Carlos F
CF
Department of Signals, System, and Radiocommunication, Polytechnical University of Madrid, Madrid 28040, Spain. cfcastillo@indra.es
Llorente-Romano
Sergio
S
Burgos-García
Mateo
M
D000465:Algorithms; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D016247:Information Storage and Retrieval / Q000379:methods*; D011825:Radar; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity