What size object can a radar detect?

[podpod]

Hi, I have a question which should fit in here:

- How big in size may an object be before it's noticed on a radar screen?

Could it detect a fly if it's designed to do that, or must the size be in a airplane dimension?

I hope that someone can think of a good answer to this question :)

 

[vincentchan]

the object must satisfly these two conditions in order to be detected by radar

1: It must reflect the radar ray... even the B2 bomber is so large, but it has a coating on its skin to absorb radar ray, therefore radar can't detect it
2: the object must much larger than the wavelength of the radar ray you used... for a normal aircraft used radar, the wave length is about 3cm...

a fly don't reflect the radiowave very well, and too small compare with the radar's wavelength

 

[Andre]

Well, it's bit more complicated than that.

http://amsglossary.allenpress.com/glossary/search?id=radar-reflectivity1

An important element is http://www.argospress.com/Resources/radar/radarcrossectio.htm . A square metal can of a few inches could have a RCS of 10m2 while a stealth fighter may have a RCS of a marble.

Radar absorbing paint may only reduce the RCS, it's not making it dissapear.

 

[podpod]

thanks guys, a lot of usefull information there ;)

 

[chroot]

Of course, the amount of power transmitted by the radar, and the radar's sensitivity to its echoes, are very important, too.

- Warren