Doppler Weather Radar - METNET - India Meteorological Department

APPENDIX A
AN OVERVIEW OF DOPPLER WEATHER RADARS
A.1. DOPPLER WEATHER RADAR SYSTEM OVERVIEW
Doppler Weather Radars are used to detect, process, distribute and display meteorological data
OVER a large area. Doppler technology opened new trends in the field of the radar meteorology
and increased the performance of weather radars significantly. Doppler weather radars are
capable of acquiring particle velocity data in addition to echo range, direction, and reflectivity
data. Software processing is used to control the radar operating characteristics to produce the
optimum radar volume coverage patterns and to optimize the radar returns. The base weather
data is then processed through the application of meteorological algorithms to generate base and
derived weather products. These products are further processed using graphics algorithms to
produce interpretable weather data displays on color monitors in the form of images. After
receipt of the reflected echo from target, the signal passes from processing stages for product
generation. These stages include many complex processes and algorithms carried out by various
weather radar software. This SOP is prepared to operate Weather Radar network of India
Meteorological Department with the uniform operations for better understanding and to create
mosaic-ing for whole DWRs network, under IMD Radar Network around the country. The
existing Cyclone Detection Radar Network in IMD shown in following Fig. A.1 and Storm
Detection & Multi-met Radar network is shown in Fig. A.2
Figure A.1 Cyclone Detection Radar Network
Network
Figure A.2 Strom Detection and Multimet Radar
Doppler Weather Radars employs high dynamic-range linear receiver and DSPs (digital signal
processors) to extract information from the received echo power. Linear receiver output in
intermediate frequency (IF) and analog form is converted to digital form in the analog-to-digital
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