This document summarizes the key components and operating principles of radar systems. It discusses the basic outline of radar including the transmitter producing pulses, a duplexer switching between transmit and receive, and a receiver amplifying returned echoes. It describes how radar determines distance based on pulse travel time. Issues like maximum unambiguous range due to pulse repetition are addressed. The document outlines the electromagnetic spectrum used, displays, antennas, emergency beacons, and navtex coding systems.

1. RADIO DETECTION AND RANGING
NAME: SHAHBAAZ LOKHANDWALA
B.TECH ECE V –SEM.
UNDER THE GUIDENCE OF DEEPIKA BANSAL

2. AGARWAL BUILDERS GROUP.LTD
INDIAN COAST GUARD SHIP -202

3. Classified Name
• 1A1-OIL REC-HELI DK (SHF)-FIFI-DYNPOS AUTS-Eo-SF-CRANE-ICS.
• 1A1 - Vessel for which periodical surveys are stipulated in relation to special (main)
periodical survey intervals of 5 years.
• OILREC - Vessel for occasional handling, storage and transportation of oil with flash
point below 60ºC recovered from a spill of oil in emergency situations.
• HELIDK-Helicopter Deck.
• DYNPOS Vessel with dynamic positioning systems
• E0 - Machinery of craft fitted with instrumentation and automation equipment
• SF - Implies classification of stability and floatability
• CRANE - Vessel with permanent cranes, when lifting operations are not a main
purpose.
• ICS - Integrated computer system.

4. Basic outline

5. Principle of RADAR
• The radar transmitter produces short duration high-power RF- pulses of energy.
• The duplexer alternately switches the antenna between the transmitter and receiver so that
only one antenna need be used. This switching is necessary because the high-power pulses
of the transmitter would destroy the receiver if energy were allowed to enter the receiver.
• The transmitted pulses are radiated into space by the antenna as an electromagnetic wave.
• The antenna receives the back scattered echo signals.
• The hypersensitive receiver amplifies and demodulates the received RF-signals.

6. Tx and Rx

7. Duplexer
TO ANTENNA
TRANSMITTER
RECIEVER

8. DISTANCE DETERMINATION
RANGE=C*TIME/2

9. Pulse repeatation Time:
The time between the
beginning of one pulse and
the start of the next pulse is
called pulse-repetition time
(PRT).
The Pulse Repetition
Frequency (PRF) of the
radar system is the number of
pulses that are transmitted
per second. They both are
inversely propotional

10. Problem with pulsed radar
• Maximum unambiguous range.: This problem is sorted
out by increasing the pulse repeatation time.
Radar waveform minimum range
Where Is the Pulse width.
A typical value of 1 µs for the pulse width of short range radar corresponds to
a minimum range of about 150 m.

11. Electromagnetic spectrum

12. Display

13. Rutter
The rotation speed is
24rpm for X band radar.
26 rpm for S band.

14. EPIRB
• Emergency Position Indicating Radio Beacon.
• A 5-Watt Radio Tran-
mitter operating at
406MHz.

15. Navtex System
• For navigation purposes, the world is divided into 16 areas.
• Each Navtex station has an identification code, from “A” to “Z”.
• The frequency assigned to Navtex are 518 kHz and another (490 or 4209.5 kHz), and
many stations exist in the same service coverage.
• For automatic identification of messages, each message starts with nine control
• characters, called “Header codes”.
• The first five characters are always “ZCZC_“ and common to all messages.
• This part is used for message synchronization. The latter four characters are
designed as B1, B2, B3 and B4 indicate origin, category and serial number of the
message.
• Character B1 is the identification letter of the Navtex station “A” thru “Z”.
• Character B2 indicates the type of message. “A” thru “Z”, as listed below.
• Character B3 and B4 indicate the serial number of the message. The serial
• numbers are counted up from “01” to “99”, and starts from “01” again.
• The end of each message is indicated by “NNNN”.

16. Navtex Coding

17. X-BAND S-BAND RADAR

18. Thank you