Doppler Weather Radar - METNET - India Meteorological Department

converter and fed to digital filters to split the power into two channels i.e., for (i) in-phase (I) and
(ii) quadrature phase(Q) components. Digital Signal Processor (DSP) chips process the raw I and
Q data and perform phase and amplitude correction, clutter filtering, covariance computation and
produce normalized results. These normalized results are tagged with angle information, headers
and given out as a data set. Covariance computation is based on pulse pair processing. Intensity
estimation consists simply of integrating the power in the linear channel (I* 2 + Q* 2 ) over range
and azimuth. The resulting power estimate is corrected for system noise, atmospheric attenuation
and transmitter power variations. The signal processing of the linear channel ends with the
estimation of reflectivity, mean radial velocity and velocity spectrum width.
Figure A.3. General signal flow chart of radar system
Figure A.4. Basic block diagram of radar
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