Radar (Radio Detection and Ranging) is a device which uses
electromagnetic waves in the microwaves region to detect location (range &
direction), altitude, intensity and movement of moving and non-moving
What is Doppler Principle?
When the source and the signal are in relative motion to each other
there is a change in the frequency observed by the observer. If they are
moving closer frequency increases and vice versa.
What is Doppler Radar?
Doppler radar is a specific radar that uses the Doppler principle to
produce relative motion data about objects at a distance.
Indian Doppler Radar:
Also known as INDRA series of 2D Radars and developed by DRDO for the
use of Airforce and the Army. Some have been even exported to Sri Lanka.
INDRA-1: Is low-level target detection mobile surveillance radar.
INDRA 2: Is a modified version of INDRA radar for ground controlled
interception of targets. It uses pulse compression to detect low flying
Application of Doppler Radars:
Radiology and healthcare
Nursing or clinic purpose
Bistatic radar (surface-to-air missile)
Doppler Weather Radar (DWR) by ISRO
For improving weather forecasting services.
The DWR will help in rainfall estimation and detect thunderstorm,
cyclones and other severe weather events within a radius of 400 km.
DWR has the equipment to measure rainfall intensity, wind shear and
velocity and locate a storm centre and the direction of a tornado or gust
Based on Doppler principle the radar is designed to improve precision in
long-range weather forecasting and surveillance using a parabolic dish
antenna and a foam sandwich spherical radome.