clipka <ano### [at] anonymousorg> wrote:
> Am 25.03.2013 06:38, schrieb Mahadeesh:
>
> > Just simple level reflectivity map calculation of the object is only im looking
> > for.. Manually creating a program for Electromagnetic imaging like say Ray
> > tracing Algorithm , Physical optics method etc is very tedious task...
> >
> > Thats why I'm planning to use POV ray for reflectivity map calculation of the
> > scene or object. From that generated reflectivity map, I was hoping to use it
> > for SAR raw echo simulation....
> >
> > Is my approach feasible one ? Thank you.
>
> I must confess that what you're saying is mostly dutch to me, and I'm
> probably not the only one here; you may need to think of us as stupid
> laymen when it comes to radar science, who need each and every technical
> term explained.
>
> What, to begin with, is a "reflectivity map" as you understand it?


Hello,

Thanks a lot for replying to my question. I would be very much happy to explain
what I know.

As you asked, Reflectivity map means the objects reflectivity property. An
object in real world has the capacity to reflect the light falling on it. Not
only light but any Electromagnetic waves falling on it. So here , Synethetic
aperture Radar (SAR)  mode is an special mode in Radar which uses microwaves as
source and uses it for creating the image. As an photographic image uses light
intensity to form an image, in SAR mode uses object reflectivity to form an
image.

The Radar sends microwaves towards the object, which potentially reflects the
microwaves based on the reflectivity property of the object. Using the energy
contained in the reflected signal (which was based on object reflectivity), SAR
image is formed.

Hence the reflectivity map is the main parameter in the complete  simulation. So
Im looking for generating reflectivity map of any object / scene. Also want to
know if there is any analogous concept in POV which can help me ?

An SAR image for your reference at this link :

https://www.google.co.in/search?q=SAR+image&hl=en&client=ubuntu&hs=bEM&channel=fs&tbm=isch&tbo=u&source=univ&sa=X&ei=Us
xaUZHQMcSIrQebm4GgDA&ved=0CDAQsAQ&biw=1067&bih=713#hl=en&client=ubuntu&hs=cZ1&channel=fs&tbm=isch&sa=1&q=synethetic+ape
rture+radar+image+&oq=synethetic+aperture+radar+image+&gs_l=img.3...14733.26980.4.27340.34.31.3.0.0.0.154.2713.29j2.31.
0...0.0...1c.1.8.img.j2PiLVDb-G4&bav=on.2,or.r_qf.&bvm=bv.44697112,d.bmk&fp=9cd1c99b78ac4f1a&biw=1067&bih=713&imgrc=kuh
ug3D1KiKnvM%3A%3BhL2JrnPfbrQReM%3Bhttp%253A%252F%252Fwww.sandia.gov%252FRADAR%252Fimages%252Fcapitol.jpg%3Bhttp%253A%25
2F%252Fwww.sandia.gov%252FRADAR%252Fimageryku.html%3B1200%3B800

Please have a look. You can note in the image that there are bright spots which
is outcome of the material property and surface. For example, the metal objects
will reflect more when compared with others. Similarily any sharp edges in the
building will produce more bounce effect which makes the spot brighter.

Regards,
M

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