ISRO RADAR DEVELOPMENT UNIT, BANGALORE. PRESENTATION TO CHAIRMAN - ISRO & MEMBERS - ISRO COUNCIL NRSA LECTURE INDO FRENCH WORKSHOP ON MEGHA TROPIQUES ISRAD

ISRO RADAR DEVELOPMENT UNIT, BANGALORE.

PRESENTATION TO CHAIRMAN - ISRO & MEMBERS - ISRO COUNCIL NRSA LECTUREINDO FRENCH WORKSHOP ON MEGHA TROPIQUES

ISRAD

GROUND VALIDATION FOR MEGHATROPIQUESUSING DOPLER WEATHER RADAR MEGHA-2700PRESENTATION BY G.VISWANATHAN – ISRAD

@SAC - BOPAL20 th OCT 2005


PRESENTATION TO CHAIRMAN - ISRO & MEMBERS - ISRO COUNCIL NRSA LECTURE

ISRAD

PRESENTATION SEQUENCE:

Genesis & Ongoing Efforts on GVMEGHA -2700, DWR @ SDSC – SHARSample Data from MEGHA - 2700Plans for GV For Megha TropiquesCAL – VAL ISSUES

GV FOR MT USING DWR MEGHA - 2700



ISRAD

Genesis

•GV efforts @ ISRO started with TRMM through then NASDA, with GV as PI from ISRO & T.Kozu from CRL• SHAR for NE Monsoon & Thumba for both SW & NE Monsoon coverage•Converted C band tracking Radars with Weather channel•Resulted in major collaboration with CRL Japan

•* IMD collaborated with NASA @ Karaikkal•MST radar (VHF Profiler along with Disdrometer (VV)

& Optical Rain gauge @ Gadanki)



ISRO RADAR DEVELOPMENT UNIT, BANGALORE. ISRAD

Ongoing Efforts:GV work continued more as an inter comparison of data from Doppler Weather Radar (Megha -2700) with TRMM as per opportunities Helped as an indirect validation of DWR Products (Z) once TRMM was well establishedCollaborative work in progress between ISRAD & Academic Institutions in India Gearing up for GV for Megha - Tropiques & GPM


PRESENTATION TO CHAIRMAN - ISRO & MEMBERS - ISRO COUNCIL NRSA LECTUREGV FOR MT USING DWR MEGHA - 2700

ISRAD

INSTRUMENTATION SYSTEMS GV Radar Systems :

S Band Doppler Weather Radar – Megha 2700Converted C Band Tracking Radar with weather channel

Other Instruments :DisdrometerFast Response RainGauges (Siphon type )Surface Observatories with TB Rain Gauges AWS Mesonet (Golden Triangle – SHAR,

Gadanki, Chennai) LIDAR NETWORK ( for Radiation/Aerosols)?



ISRAD

MEGHA – 2700 Doppler Weather Radar System@

SDSC - SHAR



ISRAD

Reflectivity Velocity Sp Width

1. Range (Km) 500 250 2502. Resolution ( m) 300 300 3002. Accuracy @23 dBZ 2 dB 1 m/s 1 m/s

@ 2 rpm3.Unambiguous maximum velocity +/- 30 m/s for 125 Km Ambiguity Resolution techniques to extend velocity to +/- 60 m/s for 125 Km or +/- 30 m/s for 250 Km.

Design goal +/- 60m/s for 250 km

DWR System SpecificationsDWR System Specifications



ISRAD

Klystron based coherent transmitterLow phase noise signal generationProgrammable waveformsHigh dynamic range Log / Lin Receiver14 bit ADCs PC-PCI bus DSP boardsPC based radar controllerData Products on Graphic WorkstationsGIS based Product overlayCalibration using built in source, Sun & Metal SphereProgrammable Antenna scan strategiesLow side lobe level Pencil beam antennaSandwich Radome to withstand gale speeds of 250 Km/hrPolarimetry to be included shortly

DWR System Features



ISRAD




ISRAD


RADOME & Antenna:

Self supporting structure 12.8m dia , with 9 m Antenna,Dual Pol FeedCurved A-type sandwich panelsInsertion loss - 0.2dB(one way)Withstands steady winds of 250 kmph gusting upto 300 kmph

Radome Developed by NAL-BangaloreFeed by LRDE & Antenna by ISRO

Antenna inside Radome @ LRDE Test Range

Horizontal Polarization Freq =2.8 GHz

-50

-40

-30

-20

-10

0

-20 -16 -12 -8 -4 0 4 8 12 16 20

Azimuth (deg)

Le

vel(

dB

)

Antenna Pattern matches well forV Polarization also



ISRAD


Rx CSG Servo 1 MW -TRANSMITTER



ISRAD

MEGHA -2700 CONTROL CONSOLE & WORK STATIONS



ISRAD

THUNDERSTORM -Z



ISRAD

THUNDERSTORM -V



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Z

RHI



ISRAD

CAPPI@1Km Rain Rate

PRECIP DATA PRODUCTS

Rainfall recorded w ith IISc rain gauge at SHAR on 06-12-2002

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

7:00 7:30 8:00 8:30 9:00 9:30 10:00 10:30 11:00 11:30 12:00 12:30 13:00 13:30 14:00 14:30 15:00 15:30 16:00 16:30

time

rain

fall

in m

m

GAUGE DATA

Z- R Relationships Selectable Based on Type of Rain Regimen with lots of choice. Rain Acc for 1hr std product



ISRAD


Echo Top in KM



ISRAD


VVP - 2FEATHER DIAGRAM

PRESENTATION TO CHAIRMAN - ISRO & MEMBERS - ISRO COUNCIL NRSA LECTURE “MEGHA – 2700”

13:05:19 UT

THUNDER STORM OF 17 OCTOBER 2002

CONVECTION CAMPAIGN

ISRAD ISRO RADAR DEVELOPMENT UNIT, BANGALORE.


13:29:07 UT

CONVECTION CAMPAIGN : THUNDERSTORM OF OCT17,2002


“MEGHA – 2700”

13:59:33 UT




14:29:13 UT



15:28:50 UT



15:55:54 UT




16:20:31 UT




16:44:50 UT




17:06:48 UT




18:03:25 UT



18:45:16 UT





ISRAD

OBSERVATION OF CYCLONES OVER BAY OF BENGAL

• CYCLONES ARE CONTINUOUSLY MONITORED USING DWR OPERATED WITH DIFFERENT SCAN STRATEGIES UNDER TIME TAGGED SCHEDULER MODE•RADAR WAVE FORM FOR EACH STRATEGY IS SO CHOSEN TO PROVIDE LONG RANGE OBSERVATIONS •DUAL PRF TECHNIQUE USED TO MINIMISE RANGE - DOPPLER AMBIGUITIES AT LONG RANGES



ISRAD

Z V

BAY OF BENGAL CYCLONE OF DECEMBER 15, 2003

V

DWR OBSERVATIONS with Dual PRFUAR = 250km & UAV = +/- 30m/s



ISRAD


Z V

CYCLONE OF DECEMBER 15, 2003

DWR Observations at Single Low PRF shows Velocity Folding due Range – Doppler ambiguities



ISRAD

GV FOR SPACE BORNE PRECIPITATION ESTIMATION EXPERIENCE WITH TRMM

DWR WAS OPERATED FOR INTERCOMPARISON WITH TRMMON A CAMPAIGN MODE OBSERVATIONS

SIMULATANEOUS MEASUREMENTS WITH FAST RESPONSERAINGAUGE & DISDROMETER CARRIED OUT

SAMPLE DATA PROVIDES A TYPICAL INTERCOMPARISON



ISRAD

PPI Plot (06 November 2003)DWR (SHAR) (307 Km)

0.5° elevation

Figure 1: PPI Plot of DWR Reflectivity over SHAR on 6th November 2003 (07:03:38 UTC)



ISRAD

0

5

10

15

20

25

30

35

40

45

50

14 N

Longitude

La

titu

de

SRI LANKA

12 N

78 E 80

E 82

E 84

E

8 N

88 E

90 E 92

E 94

E 96

E 98

E 100

E 10

N

SHAR

dBZ

PR Scan (06 November 2003)Orbit No. 34082



ISRAD

80.6 80.8 81 81.2 81.4 81.6 81.8 82 82.2 82.4 82.611.2

11.4

11.6

11.8

12

12.2

12.4

12.6

Longitude

Latit

ude

0

5

10

15

20

25

30

35

40

45

50

Longitude

Lat

itu

de

80.6 80.8 81 81.2 81.4 81.6 81.8 82 82.2 82.4 82.611.2

11.4

11.6

11.8

12

12.2

12.4

12.6

0

5

10

15

20

25

30

35

40

45

50

Longitude

FOV = 1 to 19

(a) (b)

PR dBZ at 5.5 Km heightDWR CAPPI

Magnified View of near simultaneous reflectivity observations of (a) DWR and (b) PR (TRMM) on 06 November 2003

INTERCOMPARISON WITH TRMM-PR(a)

(b)

(a) Vertical cross section of DWR (SHAR)

(b) PR for the 7th Nov 2003 event. DWR azimuth 136° corresponds to FOV 34 of PR orbit no.

34082.ISRO RADAR DEVELOPMENT UNIT, BANGALORE.


ISRAD

DIFFERENCES IN GROUND RANGE ARE DUE EARTH CURVATURE RECONNING



ISRAD

D DISDROMETER MEASUREMENTS @ SHAR

ANALYSIS COURTESY : Dr.Sanjay Sharma, Kohima Science College, Nagaland University.



ISRAD

CAL – VAL ISSUES FOR GV FOR MT

Ground Radar (GR)

TRMM PR

• VIEWING GEOMETRIES• RESOLUTION VOLUMES DUE

ANTENNA 3D PATTERNS• TIME SYNCHRONIZATION• SPATIAL ALIGNMENT & ATT

PERTURBATIONS OF S/C• OPERATING FREQUENCIES• RADIOMETRIC CALIBRATION

BOTH FOR GR & PAYLOAD

Cartoon Courtesy :Prof.Chandrasekar ,CSU



ISRAD

PLANS FOR IMMEDIATE FUTURE:

POLARIMETRIC UPGRADE FOR DWR

MESO NETWORK OF AWS WITH RAINGAUGES AROUND SHAR

INTEGRATED OBSERVATION & MODEL ASSIMILATIONFOR NOWCASTING WEATHER FOR LAUNCH SUPPORT

CO LOCATED WIND PROFILER FOR CONVECTION STUDY

GV FOR MEGHATROPIQUES

SHIPBORNE C BAND DWR ON BOARD ORV-SAGAR KANYA



ISRAD

WIND PROFILER FORSDSC - SHAR



ISRAD

INSTALL NEW DWR MEGHA-5400 ON BOARD ORV SAGAR KANYA



ISRAD

GV FOR MT USING DWR MEGHA - 2700PRESENTATION TO CHAIRMAN - ISRO & MEMBERS - ISRO COUNCIL NRSA LECTUREGV FOR MT USING DWR MEGHA - 2700

ISRAD ISRO RADAR DEVELOPMENT UNIT, BANGALOREISRO RADAR DEVELOPMENT UNIT, BANGALORE.

“ VARSHA”



ISRAD

From the sun rain is born; from rain food and from food, living

creatures- Sloka 76, Adhyaya

3, Manu Smriti

Wisdom from Ancient India



ISRAD

Documents

ISRO RADAR DEVELOPMENT UNIT, BANGALORE. PRESENTATION TO CHAIRMAN - ISRO & MEMBERS - ISRO COUNCIL NRSA LECTURE INDO FRENCH WORKSHOP ON MEGHA TROPIQUES ISRAD