What is the working principle of radars?
A. Radars are used for detection of aircrafts, ships, weather systems and a variety of other applications. Our discussion is restricted to weather radars only. Radar transmitter transmits electro-magnetic waves through a directional antenna in any given direction in a focused manner. A part of the transmitted energy is absorbed by the atmosphere. Some of the energy travels further through the atmosphere and a fraction of it is scattered backward by the targets and is received by the radar receiver. The amount of received power depends upon radar parameters like transmitted power, radar wavelength, horizontal and vertical beam widths, atmospheric characteristics etc., In case of weather echoes like clouds it depends on physical state (raindrops, snow, hail etc.) and drop size distribution hydro meteors. The amount of return power provides information about the intensity of weather systems and azimuth and elevation of the antenna gives the location and height of the cloud systems. The ti
