Images of urban areas by a synthetic aperture radar simulator

Abstract

An urban scene has a very complex variety oflength scales ranging from much bigger to much smaller than the wavelength of the radiation emitted by a Synthetic Aperture Radar (SAR). The exact solution to this scattering problem requires the solution of Maxwell's equations for the combination of source and scattering objects present in the scene, which for any reasonable size target area is computationally too large to be realistic. Hence a 'numerically exact' solution is ruled out, but, as is usual in electromagnetic problems some form of appropriate modeffing scheme is used.In this case we assume that the major contributors to the scattering are the planar surfaces which are generally many times larger than the wavelength of the radiation used. A geometrical optics ray-tracing approach is employed to calculate the incident field on each surface illuminated by the radar system whether by direct or indirect illumination (multiple bounces within the target environment goemetry). In this way the large amount of multiple scatter that arises from the combination of dihedral and trihedral corners associated with buildings is taken into account. The intensity or amplitude and polarisation characteristics of the radiation returning to the radar can be calculated by applying the Rayleigh-Rice scattering theory at each surface.

The Open-Source Framework for 3D Synthetic Aperture Radar Simulation

“…Main purpose Details Year [9] urban areas 1994 [10] realistic multisensor simulation CAD model, commercial product 2002 [11] real-time simulation GPU-based 2006 PolSARproSim [3] forest [14] general-purpose double bounce, GPU, real-time 2009 [15] geometric simulator of CAD data 2009 [16] urban scenes, large infrastructure 2011 [17] urban structures, image interpretation 2011 CohRaSS [18] large urban scenes 2012 [19] urban structures double reflection 2012 [20] speckle simulator physical approach 2013 [21] canopy simulator 2014 [22] urban structures 2016 in the form of amplitude versus range. The steps from the calculation of the reflected energy to the response generation must be repeated for every sweep, for every transmitter-receiver antenna pair.…”