Direction-determination

The angular determination of the target is determined by the directivity of the antenna. Directivity, sometimes known as the directive gain, is the ability of the antenna to concentrate the transmitted energy in a particular direction. An antenna with high directivity is also-called a directive antenna. By measuring the direction in which the antenna is pointing when the echo is received, both the azimuth and elevation angles from the radar to the object or target can be determined. The accuracy of angular measurement is determined by the directivity, which is a function of the size of the antenna.

Radar units usually work with very high frequencies. Reasons for this are:

-quasi-optically propagation of these waves.
-High resolution (the smaller the wavelength, the smaller the objects the radar is able to detect).
-Higher the frequency, smaller the antenna size at the same gain.

            Variaţia amplitudinii semnalului ecou