Radar working?

Question

principles of radar working

Answer 1

the waves of radar  can go and bounced back.the Electrical field radiation is

E=  Eo (1/r^2)x(1/r^2)

E=(1/r^4)xEo

Answer 2

Radars work on the microwave band, something around 2 cm wavelenght. It sends much energy and some is bouncing back. The sweep of the scanner is synchronised on a cathodic tube and the time it takes before an echo comes back is plotted as a radial from the center. The farther away the signal, the longer from the center it will be. That's the old method. Today, the primary radar decodes that in a so-called raster-scan decoder and digitize it to send it to a simple computer monitor. The secondary radar, such as an Automatic Radar Plotting Aid (ARPA) on a ship shows then targets with all the whistles and bells need to tag and follow the target. The same happens with aeronautical radars.

The radar signal is affected by other factors like rain and waves. That's why maritime radars have the possibility to reduce those annoying echos by adjusting the rain and sea clutter controls. But weather radars are mostly interested in the former: the position and density of rain. By measuring the doppler effect, it can also estimate the direction big cumulonimbus are moving.

Note that the radar found on airliners are not to see other aircraft but to see the weather. Heavy cumulonimbus with possibly thunderstorm are to be avoided by commercial aviation. Typically, such thundery cells will be reported by pilots or seen by the weather radar on the ground and other pilots will be advised to avoid it.

I fly a very light aircraft and such strong convective cells are very dangerous for me. Whenever I am unsure of the situation, I talk to a controller who check his radar then advise me of a better route to circumnavigate the said 'bad weather.'