Department of ECE /
Nova College of Engineering & Technology
Jupudi,Ibrahimpatnam.
mACHILIPATNAM
cdr staTION
ONE DAY VISIT REPORT

The practical vision of the technical subject in the curriculum was completed by visiting the MACHILIPATNAM CLIMATE DETECTION RADAR STATION ON 24-07-2012

Schedule of the visit to CDR Station, Machilipatnam.
7:00 AM / Among 3 busses one of the bus started from the college hostel.
8:00 AM / Busses reached near Vijayawada Bus Station.
8:30 AM / After taking the attendance of the students the busses departure to Machilipatnam with 4 members staff coordinating the 96 students.
10:30 AM / Reached Machilipatnam,CDR Station.
10:40 AM / We got a Welcome from the incharge of the CDR Station.
10:50 AM / Total students were divided into 2 batches and each batch were sent into the radar station for explanation.
11:00 AM to 11:50 AM / First batch students were given a presentation about the radar station, its working procedures and the equipments available there.
12:00 Noon to 12:50 PM / Second batch were sent for the same presentation.
Mean while the first batch students were sent for hardware block for explanation purpose 15 members at a time.
1:30 PM / First batch students were sent to lunch after completion of the visit of CDR station accompanied by 2 staff members.
2:15 PM / Second Batch students were sent to lunch after completion of the visit of CDR station accompanied by 2 staff members.
3:30 PM / Refreshments and Lunch were completed at RK Paradise, Machilipatnam.
4:00 PM / Started from RK Paradise for visiting SIVALAYAM at chilakalapudi.
4:45 PM / Reached SIVALAYAM and visited temple.
5:50 PM / Started from SIVALAYAM to PANDURANGA SWAMY TEMPLE.
6:00 PM / Reached and visited PANDURANGA SWAMY TEMPLE.
7:10 PM / Started to Vijayawada.
9:30 PM / Reached Vijayawada.
10:15 PM / Bus reached College hostel accompanied by one staff member.

Technical Report

Presentation Details about the CDR station, Machilipatnam:

  • Rader Station located in machilipatnamcomes under Indian meteorological department. The Rader System helps to give the weather for coast up to 500kmt area around it.
  • Rader means radio detection and ranging.it detects and also denotes the range of the obstacle.
  • Rader can be used to detect any obstacles such as building, trees, aircrafts, ships, clouds, hills, mountains etc. The electromagnetic signals are sent in the range of radio waves. [ie.3kh3300gh3].
  • Generally any Radersystem consists of transmitter receiver section with a single antenna for both transmission and recreation using a ‘duplexer’.
  • Rader are also capable of detecting moving objects such as aircrafts where Doppler Effect comes into act
  • Doppler Effect is the apparent change in the frequency of a wave due to the relative motion of observer source and the target.
  • Different applications where Rader’s are used are:

Tracking vehicles on ground.

To locate position of ship in sea

To guide satellites in space

Air traffic control.

Remote sensing applications

Law enforcement

In military

  • Basically random are classified into two types

Primary Radar

Secondary Radar

  • The primary radars are used for passive targets such as clouds i.e. weather reports
  • The secondary radars are used for active forgets which are used in military purpose.
  • Mainly three types of bands are there, where radars are used: X- Band

C-Band

S-Band

  • We can send either pulses as a continuous wave for detection and ranging and the antenna is capable of receiving either of the two waves.
  • The cyclone effects can be easily detected in the S-Band by the amount of precipitation and also by seeing the types of clouds formed in the atmosphere.
  • This Radar station only deals with weather forecasting it detects only clouds, precipitation, humidity etc.
  • While the reflected wave from any other obstacles would be filtered.
  • Clouds can be of three types [Mostly for Radar]

Cumulonimbus-which are toggy dangerous

Stratocumulus-just has unstable air

Nimbostratus-high precipitation

  • The height of the clouds, its depth and how for are they spread can be detected by Radar
  • To ducted the humidity, pressure, temperature etc. at different heights Radar Sande is used
  • It is an instrument tied to a big balloon which is filled with hydrogen gas and is released into the air as the balloon goes higher and higher the various parameters can be measured by the instrument near us.
  • Germany has installed the S-Band Radar network in 2004
  • This Doppler weather radar provides information on velocity and spectral width in addition to reflectivity.It has a capacity of detecting cyclones for around 500kmts
  • The globe at the top consists of the antenna which can radiate frequency of 2.87 GHz of S-Band.
  • The antenna is protected by Random which is made up of fiber as the antenna rotates for whole year continuously it needs to be protected from any damage.
  • The waves are continuously transmitted using klystron power cavity by using a parabolic shaped antenna.
  • The Radar is linearly polarized.
  • Ravis software is used for the radar.
  • Analog data/signal are received which are later converted to digital data.
  • Radar control processor (RCP) is the heart of the whole system/network.IT helps for smooth running and also informs if there are any flaws.
  • The cloud detection follows color coding
  • Blue indicate that clouds are present.
  • White indicates there may be moderate rainfall.
  • Red indicates heavy rain fall.
  • There are many other shades which may indicate the drizzling to thunderstorm rainfall from blue to red.

Climate Detecting Radar Station, Machilipatnam.

Four modules (Modulator, Klystron cavity, Receiver, Controller)

Hardware:

Internally they have showed us how the waves are generated and received back. There are four cabinets present

  • Modulator
  • Klystron
  • Receiver
  • Controller

In modulator MPS is present which gives triggered pulses and MPS also acts as compressor. This triggered unit generates and modulates pulses. As the EM waves are of high current and low voltage but the klystron requires low current and high voltage. So this modulation is done here.

  • TR tube present in modulator helps to reject the transmitted pulses entering into the receiver.
  • The frequency around2.7 to 2.9 MHZ is requires
  • Down converter helps to transform any IF to RF and vice versa (RF to IF & IF to RF)

Klystron Cabinet:

Solenoid Klystron is used for klystron cavity.

  • Trigger control is provided here and dehydrated air is passed through the aluminum covered pipes.
  • The cavity is immessed into the oil, here oils act as cooling agent.
  • Klystron consists of six cavities inside it.

Receiver Block:

  • The receiver is tuned ON only with the help of triggered pulses through DRX.
  • It has many slots as the received wave must be analyzed and the information has to be sent.
  • Duplexer a bidirectional coupler is used to know the forwarded & reflected power.
  • E-bend/H-bends are joined to a four way circulator and also a tuner is present for impedance matching at the klystron tube construction.

Controller cabinet:

The local control unit is nothing but it displays the voltage and current levels with their units that are required for each and every unit to work.

PIC: Students pictorial explaining about the working of Radar atMachilipatnam

(IV ECE Students)