This report tell u about doppler principle and signal transmission using radar transmitter

1. SUBMITTED TO: SUBMITTED BY:
Mr. ALOK KUMAR PAWAN MEENA
Ms. SUMAN GODARA (PGI/EC/12/065)
(PTS COORDINATOR)
ECE-B
1
A
PRESENTATION
ON
SUMMER TRAINING
TAKEN
AT
IMD, NEW DELHI

2. CONTENTS
 STAGE 1
◦ IMD Profile
◦ Centers Of IMD
◦ Services Provided
 STAGE 2
◦ Radar technology
◦ DWR Transmitter
2

3. STAGE 1
ABOUT THE
INDIAN METEOROLOGICAL DEPARTMENT
3

4. Company Profile
 The India Meteorological Department was establish
-ed in Calcutta in 1875
 The IMD headquarters were later shift to Shimla in
1905, then to pune in 1928 and finally to New Delhi
in 1944
 IMD became the first organisation in India to have a
message switching computer for supporting its
global data exchange.
 Now IMD is headed by the director general of
meteorology Dr. Laxman Singh Rathore
4

5. Centers
Of
IMD
RADAR
5

6. STAGE 2
6

7. RADAR
 Radar was secretly developed by several nations
before and during World War II. The
term RADAR was coined in 1940 by the United
State Navy as an acronym for Radio detection and
Ranging
 Radar is an object-detection system that uses micro-
waves to determine the range, altitude, direction, or
speed of objects.
7

8. Doppler Weather Radar:-
 Weather radar measures the scattering of microwaves
used to determine the intensity of precipitation.
 This Doppler Weather Radar is a dual polarization
weather radar that operates on the C-band RF radio
frequency (5 cm, 5.6 GHz).
 It uses a coherent klystron transmitter as the source of
microwaves.
 With sophisticated data processing techniques, the
targets can be identified as, for example, rain, hail, or
snow
8

9. Principles
 A radar system has a transmitter that emits radio
waves called radar signals in predetermined
directions.
 When these come into contact with an object they
are usually reflected or scattered in many directions.
 If the object is moving either toward or away from
the transmitter, there is a slight equivalent change in
the frequency of the radio waves, caused by
the Doppler Effect.
 The reflected radar signals captured by the receiving
antenna are usually very weak, they can be
strengthened by electronic amplifiers.
9

10. RADAR Cabinet
 1 = Waveguide dehydrator
 2 = Power distribution unit
(PDU)
 3 = Radar receiver
 4 = Radar Control
Workstation (RCW) and
console for local controlling
 5 = Solenoid power supply
 6 = HVPS power (high
voltage power supply) for
transmitter
 7 = Cooling fan
 8 = Ventilation ducts
 9 = Klystron tube
 10 = Solenoid magnet
 11=Oil tank for pulse
assembly
10

11. Transmitter
Technical and operating characteristics:
 The transmitter must have the ability to generate the
required mean RF power and the required peak
power .
 The transmitter must have a suitable RF bandwidth.
 The transmitter must be easily modulated to meet
waveform design requirements.
 The transmitter must be efficient, reliable and easy
to maintain and the life expectancy
 And cost of the output device must be acceptable.
11

12. Transmitter  1 = Inlet duct for air cooling
 2 = Centrifugal fan
 3 = Klystron tube
 4 = Solenoid magnet
 5 = Oil tank, contains the
pulse assembly
 6 = Modulator assembly
 7 = Air inlet for transmitter
and solenoid magnet cooling
 8 = Exhaust duct to the top
of the cabinet
 9 = Arc detector
 10 = Waveguide
 11 = Air inlet for modulator
cooling
12

13. Block Diagram of Transmitter
13

14. Exciter
14

15. Associated Element
 Wave guide
 Cooling subsystems
 Arc detection
 Stub tuner
 Harmonic filters
 Dehydrator
15

16. Built In Test Equipments
 RED- Alarm
 YELLOW-Warning
 GREEN- Normal
operation
Bitex Main Screen
16

17. Application Areas
 Weather surveillance network operation
 Severe weather monitoring
 Hydrometric applications
 Flood forecasting
 Airport wind shear detection (LLWAS integration)
 Hurricane/Typhoon tracking
 Hail detection
 Weather modification
 Meteorological research
 Launch support systems
17

18. Advantage
1.High quality of data
Doppler radars are used by various industries
because of the high quality of data it provides
2. Reliable weather forecasts
The data produced by Doppler radars are also
considered reliable enough in terms of forecasting
possible heavy rains, thunderstorms, and other types
of extreme weather patterns.
3. More accurate results
 Doppler radars are also used in the aviation industry
and provide accurate results in terms of managing
traffic in an airport for example.
18

19. Limitations of
Doppler Weather RADAR
 The radar though can detect wind it is only
through the radial component, thus anything
moving perpendicular to the beam is sensed as
zero velocity.
 The current radar cannot sense fog.
 All weather radars are normally with pencil
beam operation thus scan time from the lower to
the upper limit takes appreciable limits for the
cloud to get modified.
19

20. Conclusion
The radar machine give the exact location of object
and find velocity, range and position of the object. By
the radar data meteorologist forecast about flood,
cyclone, Heavy rain fall, and hail they give warning to
the people to be careful.
20

21. Key Learning and Outcome
 Learning how to work in professional environment.
 Learning the DWR technology
 Punctuality,time evaluation,priority deciding
 Helped in developing knowledege about the
RADAR technology
 Implementation of theoritical knowledge in
practical.
21

22. References
 Most of the part is taken from DWR manuals
 www.imd.com
 www.wikipedia.com
22

23. 23
THANK YOU