Airports Authority of India - Copy - Copy - Copy

7/29/2019 Airports Authority of India - Copy - Copy - Copy

1/89

bbf

SUBMITTED BY:-

SHANTANUSHRESHTH

ELECTRONICS AND COMMUNICATION ENGG.

NETAJI SUBHASH ENGG. COLLEGE

GARIA,KOLKATA-700152

PROJECT REPORT ON

COMMUNICATION, NAVIGATION

AND SURVEILLANCE(CNS

VOCATIONAL TRAINING AT REGIONAL TRAINING

CENTRE(EASTERN REGION

N.S.C.B.I. AIRPORT

KOLKATA ,BETWEEN 7-01-2013 TO 18-01-2013

AIRPORTS AUTHORITY OF INDIA


2/89

CONTENTS

1)


3/89

ABOUT AIRPORTS AUTHORITY OF INDIA

(AAI)

Airports Authority of India (AAI) was constituted by an Act of Parliament and

came into being on 1 April 1995 by merging erstwhile National Airports

Authority and International Airports Authority of India. The merger brought

into existence a single Organization entrusted with the responsibility of

creating, upgrading, maintaining and managing civil aviation infrastructure

both on the ground and air space in the country.

AAI manages 125 airports, which include 11 International Airport, 08 Customs

Airports, 81 Domestic Airports and 27 Civil Enclaves at Defense airfields. AAI

provides air navigation services over 2.8 million square nautical miles of air

space. During the year 2008- 09, AAI handled aircraft movement of 1306532

Nos. [International 270345 & Domestic 1036187], Passengers handled

44262137 Nos. [International 1047614 & Domestic 33785990] and the cargo

handled 499418 tons [International 318242 & Domestic 181176].

The Airports at Ahmedabad, Amritsar, Calicut, Guwahati, Jaipur, Trivandrum,

Kolkata & Chennai, which today are established as International Airports, are

open to operations even by Foreign International Airlines. Besides, the

International flights, National Flag Carriers operate from Coimbatore,

Tiruchirappalli, Varanasi, and Gaya Airports. Not only this but also the Tourist

Charters now touch Agra, Coimbatore, Jaipur, Lucknow, Patna Airports etc.

All major air-routes over Indian landmass are Radar covered (29 Radar

installations at 11 locations) along with VOR/DVOR coverage (89 installations)

co-located with Distance Measuring Equipment (90 installations). 52 runways


4/89

are provided with ILS installations with Night Landing Facilities at most of

these Airports and Automatic Message Switching System at 15 Airports.

AAI has undertaken GAGAN project in technological collaboration with Indian

Space and Research Organization (ISRO), where the satellite based system will

be used for navigation. The navigation signals thus received from the GPS willbe augmented to achieve the navigational requirement of aircrafts. First Phase

of technology demonstration system has already been successfully completed

in February 2008. Development team has been geared up to upgrade the

system in operational phase.

Mission: ''To achieve highest standards of safety and quality in air traffic

services and airport management by providing state-of-the-art infrastructure

for total customer satisfaction, contributing to economic growth and

prosperity of the nation.''

Vision : ''To be a world-class organization providing leadership in air traffic

services and airport management & making India a major hub in Asia Pacific

region by 2016''.

AIRPORTS AUTHORITY OF INDIA PROVIDES:-

1. Passenger Facilities


5/89

The main functions of AAI inter-alia include construction, modification &

management of passenger terminals, development & management of cargo

terminals, development & maintenance of apron infrastructure including

runways, parallel taxiways, apron etc., Provision of Communication, Navigationand Surveillance which includes provision of DVOR / DME, ILS, ATC radars,

visual aids etc., provision of air traffic services, provision of passenger facilities

and related amenities at its terminals thereby ensuring safe and secure

operations of aircraft, passenger and cargo in the country.

2. Air Navigation Services

In tune with global approach to modernization of Air Navigation infrastructure

for seamless navigation across state and regional boundaries, AAI has been

going ahead with its plans for transition to satellite based Communication,

Navigation, Surveillance and Air Traffic Management. A number of co-

operation agreements and memoranda of co-operation have been signed

with US Federal Aviation Administration, US Trade & Development Agency,

European Union, Air Services Australia and the French Government Co-

operative Projects and Studies initiated to gain from their experience. Through

these activities more and more executives of AAI are being exposed to the

latest technology, modern practices & procedures being adopted to improve

the overall performance of Airports and Air Navigation Services.

Induction of latest state-of-the-art equipment, both as replacement and old

equipments and also as new facilities to improve standards of safety of

airports in the air is a continuous process. Adoptions of new and improved

procedure go hand in hand with induction of new equipment. Some of the

major initiatives in this direction are introduction of Reduced Vertical


6/89

Separation Minima (RVSM) in India air space to increase airspace capacity and

reduce congestion in the air; implementation of GPS And Geo Augmented

Navigation (GAGAN) jointly with ISRO which when put to operation would be

one of the four such systems in the world.

3. Security

The continuing security environment has brought into focus the need for

strengthening security of vital installations. There was thus an urgent need to

revamp the security at airports not only to thwart any misadventure but alsoto restore confidence of traveling public in the security of air travel as a

whole, which was shaken after 9/11 tragedy. With this in view, a number of

steps were taken including deployment of CISF for airport security, CCTV

surveillance system at sensitive airports, latest and state-of-the-art X-ray

baggage inspection systems, premier security & surveillance systems. Smart

Cards for access control to vital installations at airports are also being

considered to supplement the efforts of security personnel at sensitive

airports.

4. Aerodrome Facilities

In Airports Authority of India, the basic approach to planning of airport

facilities has been adopted to create capacity ahead of demand in our efforts.

Towards implementation of this strategy, a number of projects for extension

and strengthening of runway, taxi track and aprons at different airports has


7/89

been taken up. Extension of runway to 7500 ft. has been taken up to support

operation for Airbus-320/Boeing 737-800 category of aircrafts at all airports.

5. HRD Training

A large pool of trained and highly skilled manpower is one of the major

assets of Airports Authority of India. Development and Technological

enhancements and consequent refinement of operating standards and

procedures, new standards of safety and security and improvements in

management techniques call for continuing training to update the knowledge

and skill of officers and staff. For this purpose AAI has a number of training

establishments, viz. NIAMAR in Delhi, CATC in Allahabad, Fire Training Centres

at Delhi & Kolkata for in-house training of its engineers, Air Traffic Controllers,

Rescue & Fire Fighting personnel etc. NIAMAR & CATC are members of ICAO

TRAINER programme under which they share Standard Training Packages

(STP) from a central pool for imparting training on various subjects. Both

CATC & NIAMAR have also contributed a number of STPs to the Central pool

under ICAO TRAINER programme. Foreign students have also been

participating in the training programme being conducted by these institution

6. IT Implementation

Information Technology holds the key to operational and managerial

efficiency, transparency and employee productivity. AAI initiated a programme

to indoctrinate IT culture among its employees and this is most powerful tool

to enhance efficiency in the organization. AAI website with domain

namewww.airportsindia.org.in orwww.aai.aero is a popular website giving
http://www.airportsindia.org.in/public_notices/aaisite_test/main_new.jsphttp://www.airportsindia.org.in/public_notices/aaisite_test/main_new.jsphttp://www.aai.aero/http://www.aai.aero/http://www.aai.aero/http://www.aai.aero/http://www.airportsindia.org.in/public_notices/aaisite_test/main_new.jsp


8/89

a host of information about the organization besides domestic and

international flight information of interest to the public in general and

passengers in particular.

Automatic Message Switching

System(AMSS)

Safe, economic and orderly movement of Air traffic depends largely on an

efficient communication system. The communication system must be able to

provide an accurate and speedy exchange of aeronautical information, such

as, Air Traffic Service (ATS) messages consists of Flight Plan, Departure and

Estimate messages etc., Meteorological messages, NOTAM messages between

stations to enable them to control the air space and movement of Air traffic

in an orderly way.

Gradually, with the advent of high speed aircrafts, increasing number of flights

in the airspace across the continent and the competitive operation of flights

to meet the commercial and tourist traffic, Air Traffic management has


9/89

become a difficult task. In order to facilitate Air Traffic Control the information

available to the Air traffic service personnel should be fast and accurate

Delayed information can lead to a disaster, both in the air and ground .To

overcome the above situation speedy and accurate flow of the aeronautica

Fixed Telecommunication Network (AFTN) messages is a must as per the

ICAO standards.

The AMSS is a computer based system, centered on the Aeronautical Fixed

Telecommunication Network (AFTN) for exchange of Aeronautical messages

by means of auto-switching for distribution of messages to its destination(s).

This system works on store and forward principle.

AMSS works on the basis of:-

1)Automation2)Message forwarding3)Switching

AUTOMATION

Automation of AMSS includes:-

1)Automation of Heading2)Automation of Text3)Automation of Address


10/89

4)Automation of Ending

MESSAGE FORWARDING

Here message is forwarded to the different work stations that may beLAN or WAN.

MESSAGE SWITCHING

There are three types of switching used:-

1)Circuit switching2)Packet switching3)Message switching

Here at airport Message switching which is based on the principle of

store and forward is used.

AMSS HARDWARE AND CONFIGURATION

SYSTEM CONFIGURATION

The ECIL AMSS setup consists of following:

AMSS Server (s).

Disk Switch.

Database Server (s).


11/89

X.25 / Communication Server.

Workstations / Nodes.

Ethernet Switch / Hub.

Communication Channel Multiplexer (CCM) Adaptor.

Line Termination Unit (LTU) Rack.

Patch Panel Rack.

Remote Printers.

Uninterrupted Power Supply (UPS).

AMSS Server

The AMSS servers are running on SCO UNIX 5.05 operating system. The ECIL

AMSS is having two servers; one is configured as SYSTEM A and other as

SYSTEM B. At one time any one of the server can be made Online and the

other Hot Standby. This is done by running appropriate Unix ShellScripts

(./n or ./r or . /h ) in respective servers. Both of the AMSS servers are

installed with Switch Over Logic Control (SOLC) cards. Depending upon

which server is online (SYS A or SYS B), both SOLC cards provide SOLC logic

to the LTU rack. This logic connects the online server to the

outgoing/incoming channel in the LTU rack. The Online and Hot Standby

servers communicate health to each other through SOLC cards. The AMSS

server is installed with Stallion card as communication controller module to

serve multiple numbers of channels. Both the AMSS servers are individually


12/89

connected to parallel printers. The system generated health / activity

information are printed on these printers.

Disk Switch

The SCSI disks are referred as DISK 0 and DISK 1. Each SCSI disk and its

corresponding connector are housed in a single cabinet and as a whole

referred as Disk Switch. The SCSI Disk 0 ishoused in Disk Switch 01 and

Disk 1 is housed in Disk Switch 02 respectively.

The function of the Disk Switch is to store the following information for

certain number of days;-

Line status for each channel.

Down time

Break status

Number of rejected messages per day

Hourly incoming total

Incoming total

Outgoing total

Peak hour incoming total

Expected incoming sequence number

Expected outgoing sequence number

Count of SVC messages (incoming / outgoing)


13/89

Incoming closed

Outgoing closed

Route status for each route

Blocked

Auto diversion enabled

Divert priority

Status of the diverted route

FOR MESSAGES IT STORES:-

Incoming and outgoing messages are recorded in the message area.

Size of the message area depends on

Maximum number of messages to be stored

Average length of message.

Number of days the message has to be stored.

ETHERNET SWITCH

Switching is a cost effective way of increasing the total network capacity

available to users on a LAN. A switch increases the LAN new capacity and

decreases the network loading by making it possible for a LAN to be

divided into different segments, which dont compete with each other.

24 port 10/100 MBPS fast Ethernet switch is designed for the departmental

and enterprise connection. These switches combine a high level of flexibility


14/89

with manageability, plus a Gigabit port for backbone connection. They

eliminate network bottlenecks while giving users the capability to fine-tune

performance.

The ports negotiate between 10 BASE-T and 100 BASE-TX network speeds,

as well as between full duplex and half duplex. These switches use store and

forward switching method. RAM buffer is dynamically allocated for each port.

Network is configured by auto learning.

POWER SUPPLY UNITS

Dual power supply units for supply of (+/- 60V, +/-12V and +5V ) is

provided in LTU rack . 60V for remote lines, 12V for RS232C serial

communication and 5V for supply to LTI cards.

MODEM

MODEM is used as external or internal device to interface with low speed

lines in our AMSS system to communicate with the remote terminals. In ECIL

system external MODEM is used at very few stations.

SCO UNIX OPERATING SYSTEM


15/89

This is the basic operating system used exclusively in the system server used

by the system administrator. The version is 5.05 environment.

APPLICATION SOFTWARE

Application software has been customized exclusively by ECIL. Software is

designed around UNIX environment and language used is C++.

AUDIO VISUAL ALARM (AVA)

The Audio Visual Alarm (AVA) software monitors and displays the status of

the entire message switching system including its various allied sub-systems.

The AVA displays

1) Switch status- MS1 and MS22) Device Status-Disks and Tapes3) Power Supply status4) Real time5) Channel status


16/89

MULTI-CHANNEL COMMUNICATION CONTROLLER

MULTIPLEXER

The basic job of CP is to multiplex characters received from serial lines andinforms the main processor about reception of a fixed (256) number of

characters or when a fixed string (NNNN) has been detected.

The CP is provided with 64 Channel multiplexes (16/32/64CCM) cards in the

On-line and Hot-standby systems for supporting up to 64 asynchronous

channels of different speeds from 50BPS to 9600BPS. Also reject printer for

diagnostic report and report printer for activity log is also connected to

communication sub system. The dial up and COPB circuits are supported

through these communication controllers only. Since the communication

controllers are available in both on-line and hot-standby systems, the failure

of any communication multiplexes forces that switch over and hence does not

hamper the availability of AMSS

LINE TERMINATION UNIT (LTU)

LTU rack with a capacity to support 64 channels is provided in view of the

future expansion. By adding additional line termination cards (LTU-B/C) and

associate communication multiplexers the system capacity can be enhanced.

The software supplied supports up to 128 lines. By simple updating the


17/89

database, routing directory, the system capacity can be enhanced to 128

channels.

There is one LTU for each line. LTU B/C interface supports two types ofchannels. LTUB serves the function of converting Baudot code interface to

RS232C interface. This unit also provides line isolation, over voltage, current

protection etc; LTU-C is basically RS232 to RS232 with functions of line

isolation TX signal selection (online systems TX signal only allowed to the

external line) and other protection facilities.

The LTU rack consists of its own power supply modules and three types of

line termination units, LTU-C, LTU-B/C/M, and LTU-D. The term B/C/M refers

to the modes of LTU operation. All of these LTU cards are terminated on the

same back plane motherboard in the LTU rack.

Here at airport LTU works in C mode of operation.

Remote Printers

The ECIL AMSS is incorporated with Report Printer; Reject Printer located in

supervisor position and Drop Printers located in other positions as required.

These printers are referred as Remote Printers. The remote printers are

connected to UNIX server through LTU C.

Workstation Workstation Workstation Workstation Workstation

SUPERVISOR NOTAM

BOOKING

HFRT OTHERSMET

BOOKING


18/89

1 TO 16 1 TO 16

CHANNEL CHANNEL

TO REJECT / REPORT &

TO LEASED TP LINE OTHER REMOTE PRINTERS. TO X.25 LINE

F IGURE: BLOCK DIAGRAM OF ECIL AMSS

NIC

AMSS

SERVER A

SERVER BOARD

SOLC

NIC

AMSS

SERVER B

SERVER BOARD

SOLC

NIC

DATABASE

SERVER

SERVER BOARD

RAID

NIC

X.25 SERVER

SERVER BOARD

RAID

CCM

ADAPTER

CCM

ADAPTER

LTU D LTU B/C/M LTU C POWER SUPPLY

DATA/VOICE

MUX

PATCH PANEL RACK

System Printer

System Printer

SCSI SCSI


19/89

COMMUNICATION BREIFING

The main function of this department is to approve the flight plans

registered by all the aircrafts before take-off. Other functions include

checking and correcting flight routes mentioned on the flight plan.

NOTAM messages are received and approved from this department, and

the corresponding officials are responsible for conveying these NOTAM

messages to the pilots beforehand.

The flight plan is once uploaded in the database of the system and

generated by the system itself for scheduled flights.

New flight plan has to be uploaded in the database for non-scheduled

or emergency flights.

The main information provided in the flight plan is as

follows:

1. 7 letter Aircraft Identification Code

2. Flight Rules - I (IFR), V (VFR) or Y (Both)

3. Type of Flight N (Non Scheduled), S (Scheduled) or M (Military)

4. Number Denotes number of aircraft (1 for normal flights, more for

formation flights)

5. Type of Aircraft Boeing (B737), Airbus (A320, A380), ATR flights

(AT72), etc.


20/89

6. Category L (Light, less than 7000Kg), M(Medium, 7000-136000Kg) or

H(Heavy, greater than 136000Kg)

7. Equipment N (NDB), V (DVOR), I (ILS), etc.

8. Departure Aerodrome (4 letter Airport Identification Code)

9. Time Time of departure in GMT

10. Cruising Speed (expressed in Nautical Miles per hour)

11. Level Denotes flight level or the altitude

12. Route The full route from source to destination, via all the major

airports

13. Destination Aerodrome (4 letter Airport Identification Code)

14. Estimated time to reach destination aerodrome

15. 1st alternate aerodrome

16. 2nd alternate aerodrome


21/89


22/89

NOTAM

NOTAM or Notice to Airmen are notices distributed by means of

telecommunication containing information concerning the establishment,

condition or change in any aeronautical facility, service, procedure or

hazard, the timely knowledge of which is essential to personnel

concerned with flight operations.

NOTAMs are issued (and reported) for a number of reasons, such as:

1. Hazards such as air-shows, parachute jumps, kite flying, rocket

launches, etc.

2. flights by important people such as heads of state

(sometimes referred to as TemporaryFlight Restrictions, TFRs)

3. closed runways

4. inoperable radio navigational aids

5. military exercises with resulting airspace restrictions

following information is promulgated by Notam:

1. Establishment, withdrawal and significant changes in operation ofaeronautical services;

2. Establishment, closure or significant changes in operation ofaerodrome(s) or runways;


23/89

3. Establishment or withdrawal of electronic and other aids to airnavigation and aerodromes;

4. Establishment, withdrawal or significant changes made to visual aids;5. Interruption of or return to operation of major components of

aerodrome lighting systems;6. Establishment, withdrawal or significant changes made to procedures

for air navigation services;

7. Occurrence or correction of major defects or impediments in themaneuvering area;

8. Changes to and limitations on availability of fuel, oil and oxygen;9. Major changes to search and rescue facilities and services available;10. Establishment, withdrawal or return to operation of hazard

beacons marking significant obstacles to air navigation;

11. Changes in regulations requiring immediate action;12. Presence of hazards which affect air navigation (including

obstacles, military exercises, displays, races, major parachuting events

outside promulgated sites);

13. Erecting, removal of or changes to significant obstacles to airnavigation in the take-off/climb, missed approach, approach areas

and runway strip;

14. Establishment or discontinuance (including activation ordeactivation) as applicable, or changes in the status of prohibited,

restricted or danger areas;

15.

Establishment or discontinuance of areas or routes or portionsthereof where the possibility of interception exists and where the

maintenance of guard on the VHF emergency frequency 121.5 MHz is

required;

16. changes in hazardous conditions due to snow, slush, ice or wateron the movement area;


24/89

17. Outbreaks of epidemics necessitating changes in notifiedrequirements for inoculations and quarantine measures;

18. Forecasts of solar cosmic radiation, where provided;19. Occurrence of pre- eruption volcanic activity, the location, date

and time of volcanic eruptions and the existence, density and extentof volcanic ash cloud, including direction of movement, flight levels

and routes or portions of routes which could affected;

20. Release into the atmosphere of radioactive materials or toxicchemicals following a nuclear or chemical incident, the location, date

and time of the incident, the flight levels and routes or portions

thereof which could be affected and the direction of movement.


25/89

VHF

(RANGE: 30-300 MHz)

Very high frequency (VHF) is the radio frequency range from 30 MHzto 300 MHz. Commonly it is used in FM broadcasting ,mobile stations that

may be military.private or emergency mobile, long range data communication

with radio modems, amateur radio, marine communications, air traffic control

communications and air navigation systems (e.g. VOR, DME & ILS).It is a line

of sight communication system. Due to its high penetratin power in can not

be used in skywave propagation.

In the VHF band:

- 108-156 MHz Communication band

-118-137 MHz Aeronautical band

-137-156 MHz Upper Military band


26/89

At airport the description of distribution of VHF frequency band is as

under:-

SMC, 121.9 MHz

Surface Movement Control, . It is used to monitorand control aircrafts in the apron. For examplefollow me jeep.

Tower, 118.1 MHz

Tower functions on both instrumental as well as visual aids. All major

international airports have the same SMC and Tower frequency. It covers a

range of radius 10NM.

Approach, 127.9MHz (119.3 stand by)

After Tower, control is transferred to Approach Control. Approach

Control has its own radar which has a fixed and a standby frequency. Its

range is 10NM 50NM.

Area Control

Area Control takes charge after 50NM. Its range is 50NM 250NM.

Since the area of coverage is vast, it is nearly impossible for a controller to

monitor and control all of the aircrafts in this range. Hence, area is divided

into 3 regions- East, West & South.

Feeder, 127.3MHzFeeder is also known as PBN or Performance Based Navigation system.

When an aircraft establishes connection at Feeder frequency, it is provided

with GPS; hence no further aid is required.

DATIS, 126.4MHz


27/89

DATIS or Digital Airport Terminal Information System is always operated

in broadcast mode. Every half an hour updated information is broadcasted.

Emergency, 121.5MHz

This is emergency or distress frequency. When there is immediate need

for aircraft to contact controller, this frequency is used. This frequency

The VHF frequencies available at Kolkata airport are

118.1 MHz Tower

119.3 MHz Approach (standby)

119.5 MHz Monopulse Secondary Surveillance Radar (MSSR)

120.1 MHz Area Control (West)

120.7 MHz Area Control (East)

121.5 MHz Distress (Emergency Frequency)

121.9 MHz Surface Movement Control (SMC)

125.9 MHz Area (East standby)

126.1 MHz Area (West standby)

126.4 MHz Digital Airport Terminal Information System (DATIS)

127.3 MHz Feeder


28/89

127.9 MHz Approach

132.45 Area (South)

VHF TRANSMITTER


29/89

The function of a transmitter is to perform process of modulation and to

raise power level of the modulated signal to the desired extent for

effective radiation.

They may use low level or high level modulation.

The figure 16 (a) shows block diagram of a typical A.M. transmitter. A

crystal oscillator generates the carrier frequency or its multiple. It is

followed by a Buffer amplifier and a tuned driver amplifier. After this a

class C modulator amplifier is used which is generally a collector

modulator. The audio signal is amplified by a chain of amplifiers and a

power. Amplifier usually transformer coupled class B push pull power

amplifier is used for power amplification.

Now, the output of the final class C amplifier is passed through an

impedance matching net work which includes the tank circuit of the fina


30/89

amplifier. The Q-factor of this circuit should be low enough so that all

the sidebands of the signal are passed without any type of distortion.

The negative feedback is often used to reduce distortion in class C

modulator system . The -4Dack is troduc1 as own is Figure (b). A

sample of R1 signal sent to the antenna is extracted and demodulated

to produce the feedback.

RECEIVER

1)Superheterodyne receiver is used for more accuracy than Tunedfrequency receiver

2) It has two stages:---- IF stage and RF stage


31/89

IF stage has a property of sensitivity.It is tuned to a particular

frequency.Hence only respond to a certain frequency.

--- RF stage:-

This is mainly used for the rejection of unwanted frequency which isnamed as IMAGE FREQUENCY.

Also at this stage it rejcects the adajecent channel.

HFRT COMMUNICATION

(FREQUENCY RANGE : 3-30 MHz)

HFRT communication that is High Frequency Radio Telephony

communication.To communicate with an aircraft beyond 200 NM


32/89

distance it is used. The reason it is used because its penetrating power

is less than VHF signal so can be reflected by the ionosphere

SOME POINTS ABOUT HFRT:-

HFRT is very noisy because transmission is done using Ionospheric

reflection.

-- The difference in elevation levels that can be assigned to flights in the

same direction is 1000 ft and in the opposite direction is 2000 ft.

-- The minimum horizontal separation between two aircrafts is 10 NM.

: The minimum distance from a Transmitter, at which reception is

received after reflection from the ionosphere is the Skip Distance.

The whole HFRT communication is divided into 2 categories:-

1)MWARA:- It stands for Major World Air Route Area. This area hasbeen allocated to the International flights. At N.S.C.B.I. airport the

available frequencies for MWARA are:-

a) 10066 KHz day(main)

b) 6556 KHz - day(standby)

c) 3491 KHz -night(main)

d) 2947 KHz - night (standby)


33/89

2)RDARA:- Regional Domestic Air Route AreaThis is used for domestic flights. The available frequencies for RDARA at

Netaji Subhash Chandra Bose International airport at Kolkata are

a. 8869 KHz

b. 6583 KHz

c. 8948 KHz

d. 5580 KHz

e. 2872 KHz

TRANSMITTING AND RECEIVING STATION

REMOTE TRANSMITTING STATION:- It is the transmitting station used for

transmitting the message or signal to the aircraft which originates from

communication centre.

COMMUNICATION CENTRE TRANSMITTING STATIONAIRCRAFT

RECEIVING STATION


34/89

REMOTE RECEIVING STATION:- It is the receiving station which receives the

signal or message from aircraft

and deliver it to the communication centre.

HF RECEIVER

ICOM-R9000 is used at the receiving statio (GARUI). It is a wideband as well

as superheterodyne receiver.Its frequency range is 100 KHz to 1999.9 MHz .

This receiver is used in following mode :-

1)USB2) LSB


35/89

3)CW4)FSK5)AM6)FM7)WIDE FMThe specification ofICOM-R9000 is as follows:-

1)Sensitivity- 2V (minimum amplitude at which receiver works)2)

Audio output power 2.5 W

3) Audio output impedance 4-8 ohms4) Power Supply for DC 13.8V and 220-240V for AC5) Antenna impedance (unbalanced) 50ohms6) Power Consumption < 110 VA7) Frequency Stability in 100KHz-30MHz (HF band) is 25Hz8) Number of memory channels 1000, broken into slots of 100

9) Receiver uses Squelch system. In telecommunications, squelch is a circuitfunction that acts to suppress the audio (or video) output of a receiver in

the absence of a sufficiently strong desired input signal.

SUPERHETERODYNE RECEIVER


36/89

Fig: superheterosyne receiver

Fig:- I COM R9000 RECEIVER

Functions of some hardware of I COM R9000 RECEIVER:-

1)Power Switch: Its working voltage is 13.8 volts.


37/89

2)Squelch: It disconnects the speaker when there is no signal and whensignal is received then squlch generates a voltage which energise the relay

and speaker is connected.

3)Automatic Gain Control: It is used to control the gain.4)Notch:- It is used to control the reception.whenever there is undesirable

rise in reception it controls that.

HF TRANSMITTER

ANTENNA

DFS DRIVER

-1

DRIVER-2

P.A. REFLEC

TOM-

FILTER

REFLECTOM

TER-2

MATCHING

UNITBALUM


38/89

The transmitter used at the transmitting station at GARUI is Zenital CST-

2002A.

The highest power that can be transmitted from this transmitter is2.5KW.

The hardware description shown in tha block diagram above is as follows:-

1)DFSHere, the transmitter uses a Digital Frequency Synthesizer (DFS) togenerate the carrier frequency instead of an oscillator. This DFS uses DDS

technology. Direct Digital Synthesizer (DDS) is a type of frequency

synthesizer used for creating arbitrary waveforms from a single, fixed-

frequency reference clock. Applications of DDS include: signal generation,

local oscillators in communication systems, function generators, mixers,

modulators, sound synthesizers and as part of a digital phase-locked loop.

2) Driver 1 Supply Voltlage=24V DC Maximum Gain=26 dB Class AAmplifier

3) Driver 2- Supply Voltlage=48V DC Maximum Gain=17 dB Class AAmplifier

4) Power Amplifier (PA)- Supply Voltlage=48V DC Maximum Gain=13.5 dBClass AB Amplifier

5) Refectometer1- Reflection coefficient is measured here.6) Filter- To eliminate the harmonics which have been introduced in the

amplifier stages.

7) Reflectometer 2


39/89

8) Matching Unit- Impedance matching for Maximum Power Transfer9) Balum Conversion from balanced to unbalanced line is done by it.


40/89

DME

(FREQUENCY RANGE: 962-1215 MHz)

Distance measuring equipment (DME) is a transponder-based radio navigation

technology that measures slant range distance by timing the propagation

delay of VHF or UHF radio signals.

DME is similar to secondary radar, except in reverse. The system was a post-

war development of the IFF (identification friend or foe) systems of World War

II. To maintain compatibility, DME is functionally identical to the distance

measuring component of TACAN.

Aircraft use DME to determine their distance from a land-based transponder

by sending and receiving pulse pairs two pulses of fixed duration and

separation. The ground stations are typically co-located with VORs. A typical


41/89

DME ground transponder system for en-route or terminal navigation will have

a 1 kW peak pulse output on the assigned UHF channel.

A low-power DME can also be co-located with an ILS glide slope antenna

installation where it provides an accurate distance to touchdown function,

similar to that otherwise provided by ILS Marker Beacons.

Hardware

The DME system is composed of a UHF transmitter/receiver (interrogator) in

the aircraft and a UHF receiver/transmitter (transponder) on the ground.

Timing

The aircraft interrogates the ground transponder with a series of pulse-pairs

(interrogations) and, after a precise time delay (typically 50 microseconds), the

ground station replies with an identical sequence of pulse-pairs. The DME

receiver in the aircraft searches for pulse-pairs (X-mode= 12 microsecond

spacing) with the correct interval between them, which is determined by each

individual aircraft's particular interrogation pattern. The aircraft interrogator

locks on to the DME ground station once it recognizes a particular reply pulse

sequence has the same spacing as the original interrogation sequence. Once

the receiver is locked on, it has a narrower window in which to look for the

echoes and can retain lock.
http://en.wikipedia.org/wiki/Transponderhttp://en.wikipedia.org/wiki/Transponderhttp://en.wikipedia.org/wiki/Transponder


42/89

Distance calculation

A radio signal takes approximately 12.36 microseconds to travel 1 nautical

mile (1,852 m) to the target and backalso referred to as a radar-mile. Thetime difference between interrogation and reply, minus the 50 microsecond

ground transponder delay, is measured by the interrogator's timing circuitry

and converted to a distance measurement (slant range), in nautical miles, then

displayed on the cockpit DME display.

The distance formula, distance = rate * time, is used by the DME receiver to

calculate its distance from the DME ground station. The rate in the calculation

is the velocity of the radio pulse, which is the speed of light (roughly

300,000,000 m/s or 186,000 mi/s). The time in the calculation is (total time

50s)/2.
http://en.wikipedia.org/wiki/Nautical_milehttp://en.wikipedia.org/wiki/Nautical_milehttp://en.wikipedia.org/wiki/Slant_rangehttp://en.wikipedia.org/wiki/Metre_per_secondhttp://en.wikipedia.org/wiki/Milehttp://en.wikipedia.org/wiki/Milehttp://en.wikipedia.org/wiki/Metre_per_secondhttp://en.wikipedia.org/wiki/Slant_rangehttp://en.wikipedia.org/wiki/Nautical_milehttp://en.wikipedia.org/wiki/Nautical_mile


43/89

The accuracy of DME ground stations is 185 m (0.1 nmi).[2]It's important to

understand that DME provides the physical distance from the aircraft to the

DME transponder. This distance is often referred to as 'slant range' and

depends trigonometrically upon both the altitude above the transponder and

the ground distance from it.

For example, an aircraft directly above the DME station at 6076 ft (1 nmi)

altitude would still show 1.0 nmi (1.9 km) on the DME readout. The aircraft is

technically a mile away, just a mile straight up. Slant range error is most

pronounced at high altitudes when close to the DME station.
http://en.wikipedia.org/wiki/Nautical_milehttp://en.wikipedia.org/wiki/Distance_measuring_equipment#cite_note-FRS2001-2http://en.wikipedia.org/wiki/Distance_measuring_equipment#cite_note-FRS2001-2http://en.wikipedia.org/wiki/Distance_measuring_equipment#cite_note-FRS2001-2http://en.wikipedia.org/wiki/Distance_measuring_equipment#cite_note-FRS2001-2http://en.wikipedia.org/wiki/Nautical_mile


44/89

Radio-navigation aids must keep a certain degree of accuracy, given by

international standards, FAA,[3] EASA, ICAO, etc. To assure this is the

case, flight inspection organizations check periodically critical parameters with

properly equipped aircraft to calibrate and certify DME precision.

ICAO recommends accuracy of less than the sum of 0.25 nmi plus 1.25% of

the distance measured.

Fig: DME

DVOR

FREQUENCY RANGE(112-118 MHz)

VHF omnidirectional radio range (VOR), is a type of

short-range radio navigation system for aircraft, enabling aircraft to determine
http://en.wikipedia.org/wiki/Distance_measuring_equipment#cite_note-FAA_Order_9840.1-3http://en.wikipedia.org/wiki/Distance_measuring_equipment#cite_note-FAA_Order_9840.1-3http://en.wikipedia.org/wiki/European_Aviation_Safety_Agencyhttp://en.wikipedia.org/wiki/International_Civil_Aviation_Organizationhttp://en.wikipedia.org/wiki/Flight_inspectionhttp://en.wikipedia.org/wiki/International_Civil_Aviation_Organizationhttp://en.wikipedia.org/wiki/International_Civil_Aviation_Organizationhttp://en.wikipedia.org/wiki/Flight_inspectionhttp://en.wikipedia.org/wiki/International_Civil_Aviation_Organizationhttp://en.wikipedia.org/wiki/European_Aviation_Safety_Agencyhttp://en.wikipedia.org/wiki/Distance_measuring_equipment#cite_note-FAA_Order_9840.1-3


45/89

their position and stay on course by receiving radio signals transmitted by a

network of fixed ground radio beacons, with a receiver unit. It uses radio

frequencies in the very high frequency (VHF) band from 108 to 117.95 MHz.

Developed in the US beginning in 1937 and deployed by 1946, VOR is the

standard air navigational system in the world,[1][2] used by both commercial

and general aviation. There are about 3000 VOR stations around the world.[1]

A VOR ground station sends out a master signal, and a highly

directional second signal that varies in phase 30 times a second compared to

the master. This signal is timed so that the phase varies as the secondary

antenna spins, such that when the antenna is 90 degrees from north, the

signal is 90 degrees out of phase of the master. By comparing the phase of

the secondary signal to the master, the angle (bearing) to the station can be

determined. This bearing is then displayed in the cockpit of the aircraft, and

can be used to take a fix as in earlier radio direction finding (RDF) systems,

although it is, in theory, easier to use and more accurate. This line of position

is called the "radial" from the VOR. The intersection of two radials from

different VOR stations on a chart provides the position of the aircraft. VOR

stations are fairly short range, the signals have a range of about 200 miles.

There are two siganal:-

Reference signal maintains same phase throughout the azimuth- frequency

fc

Variable signal varies its phase according to the azimuth- frequency fc9960

The figure is shown in the next page.


46/89

Here change in phase of the variable signal is measured with respect to the

phase .The transmitter on the ground produces and transmits a signal, oractually two separate signals, which make it possible for the receiver to

determine its position in relation to the ground station by comparing the

phases of these two signals.

The figure is shown in the next page.


47/89

VOR stations broadcast a VHF radio composite signal including the

station's identifier, voice (if equipped), and navigation signal. The identifier is

typically a two- or three-letter string in Morse code. The voice signal, if used,

is usually the station name, in-flight recorded advisories, or live flight service

broadcasts. The navigation signal allows the airborne receiving equipment to

determine a magnetic bearing from the station to the aircraft (direction from

the VOR station in relation to the Earth's magnetic North at the time of


48/89

installation). VOR stations in areas of magnetic compass unreliability are

oriented with respect to True North.

DVOR means Doppler VOR is the second generation VOR, providing

improved signal quality and accuracy. The REF signal of the DVOR is

amplitude modulated, while the VAR signal is frequency modulated. This

means that the modulations are opposite as compared to the conventional

VORs. The frequency modulated signal is less subject to interference than the

amplitude modulated signal and therefore the received signals provide a

more accurate bearing determination.

The Doppler effect is created by letting the VAR signal be electronically

rotated, on the circular placed aerials, at a speed of 30 revolutions per

second. With a diameter of the circle of 13.4 meters, the radial velocity of the

VAR signal will be 1264 m/s. This will create a Doppler shift, causing the

frequency to increase as the signal is rotated towards the observer and

reduce as it rotates away with 30 full cycles of frequency variation per second.

This results in an effective FM of 30 Hz. A receiver situated at some distance

in the radiation field continuously monitors the transmitter. When certain

prescribed deviations are exceeded, either the IDENT is taken off, or the

complete transmitter is taken off the air.


49/89


50/89

Fig: dvor antenna


51/89

ILS(INSTRUMENT LANDING SYSTEM)

(Frequency range: Markers 75 MHz, Localizer 108-112 MHz, Glide

Path 328-336 MHz)

An instrument landing system (ILS) is a ground-based instrument

approach system that provides precision guidance to an aircraft approaching

and landing on a runway, using a combination of radio signals and, in many

cases, high-intensity lighting arrays to enable a safe landing during instrument

meteorological conditions (IMC), such as low ceilings or reduced visibility due

to fog, rain, or blowing snow.

Instrument approach procedure charts (or approach plates) are published for

each ILS approach, providing pilots with the needed information to fly an ILS

approach during instrument flight rules (IFR) operations, including the radio

frequencies used by the ILS components or navaids and the minimum

visibility requirements prescribed for the specific approach.

Radio-navigation aids must keep a certain degree of accuracy (set byinternational standards of CAST/ICAO); to assure this is the case, flight

inspection organizations periodically check critical parameters with properly

equipped aircraft to calibrate and certify ILS precision.


52/89

OPERATION:-

An ILS consists of two independent sub-systems, one providing lateral

guidance (localizer), the other vertical guidance (glide slope or glide path)

to aircraft approaching a runway. Aircraft guidance is provided by the ILS

receivers in the aircraft by performing a modulation depth comparison.

A localizer (LOC, or LLZ until ICAO designated LOC as the official acronym)[1]

antenna array is normally located beyond the departure end of the runway

and generally consists of several pairs of directional antennas. Two signals are

transmitted on one out of 40 ILS channels in the carrier frequency range

between 108.10 MHz and 111.95 MHz (with the 100 kHz first decimal digit

always odd, so 108.10, 108.15, 108.30, and so on are LOC frequencies but

108.20, 108.25, 108.40, and so on are not). One is modulated at 90 Hz, the

other at 150 Hz and these are transmitted from separate but co-located

antennas. Each antenna transmits a narrow beam, one slightly to the left of

the runway centerline, the other slightly to the right.

The localizer receiver on the aircraft measures the difference in the depth of

modulation (DDM) of the 90 Hz and 150 Hz signals. For the localizer, the

depth of modulation for each of the modulating frequencies is 20 percent.
http://en.wikipedia.org/wiki/Localizerhttp://en.wikipedia.org/wiki/Localizerhttp://en.wikipedia.org/wiki/Localizerhttp://en.wikipedia.org/wiki/Localizer


53/89

The difference between the two signals varies depending on the position of

the approaching aircraft from the centerline.

If there is a predominance of either 90 Hz or 150 Hz modulation, the aircraft

is off the centerline. In the cockpit, the needle on the horizontal situation

indicator (HSI, the instrument part of the ILS), or course deviation indicator

(CDI), will show that the aircraft needs to fly left or right to correct the error

to fly down the center of the

runway. If the DDM is zero, the aircraft is on the centerline of the localizer

coinciding with the physical runway centerline.

is sited to one side of the runway touchdown zone. The GP signal is

transmitted on a carrier frequency between 328.6 and 335.4 MHz using a

technique similar to that of the localizer. The centerline of the glide slope

signal is arranged to define a glide slope of approximately 3 above

horizontal (ground level). The beam is 1.4 deep; 0.7 below the glideslope

centerline and 0.7 above the glideslope centerline.

These signals are displayed on an indicator in the instrument panel. This

instrument is generally called the omni-bearing indicator or nav indicator. The

pilot controls the aircraft so that the indications on the instrument (i.e., the

course deviation indicator) remain centered on the display. This ensures the

aircraft is following the ILS A glide slope (GS) or glide path (GP) antenna

array centreline (i.e., it provides lateral guidance). Vertical guidance, shown on

the instrument by the glideslope indicator, aids the pilot in reaching the


54/89

runway at the proper touchdown point. Many aircraft possess the ability to

route signals into the autopilot, allowing the approach to be flown

automatically by autopilot.

Glide path landing


55/89

MARKERS

Marker Beacons

Marker beacons are used to alert the pilot that an action (e.g., altitude

check) is needed. This information is presented to the pilot by audio andvisual cues. The ILS may contain three marker beacons: inner, middle and

outer. The inner marker is used only for Category II operations. The marker

beacons are located at specified intervals along the ILS approach and are


56/89

identified by discrete audio and visual characteristics (see the table below). All

marker beacons operate on a frequency of 75 MHz.

Indications a pilot receives when passing over a marker

beacon.

MARKER CODE LIGHT SOUND

OM _ _ _ BLUE400 Hz

two dashes/second

MM ._._._ AMBER1300 Hz

Alternate dot and dash

IM . . . . WHITE3000 Hz

only dots

BC . . . . WHITE

Notice above that the sound gets "quicker" and the tone "higher"

as the aircraft moves towards the airportfirst dashes, then dots and dashes,

finally just dots.

Click the beacon indicators to hear their tones.

The OM, 4 to 7 NM from the runway threshold, normally indicates

where an aircraft intercepts the glide path when at the published altitude.
http://www.navfltsm.addr.com/innermk.wavhttp://www.navfltsm.addr.com/middmk.wavhttp://www.navfltsm.addr.com/outermk.wavhttp://www.navfltsm.addr.com/innermk.wavhttp://www.navfltsm.addr.com/middmk.wavhttp://www.navfltsm.addr.com/outermk.wavhttp://www.navfltsm.addr.com/innermk.wavhttp://www.navfltsm.addr.com/middmk.wavhttp://www.navfltsm.addr.com/outermk.wav


57/89

The MM, 3500 feet from the runway threshold, is the Decision Height point

for a normal ILS approach. On glide path at the MM an aircraft will be

approximately 200 feet above the runway.

The IM. 1000 feet from the runway threshold, is the Decision Height

point for a Category II approach. See later for description of categories of ILS

approaches.

BC ... Most, but not all, airports with an ILS also offer guidance on the back

course. The BC marker identifies the FAF for the back course. A Back-Course

approach is non-precision since there is no glide path associated with it.

Decision Height

The ILS brings in a brand new term, Decision Height, or DH as you will always

hear it from here on. Thus far, the altitude published in the minimums section

of the approach plates that you have used has been the MDA, or Minimum

Descent Altitude. When flying a non-precision approach, you are not

authorized to descend below the MDA unless you can see the runway or the

approach lights and make a normal landing.

DH has a similar meaning. The DH for an ILS approach is a point on the glide

slopedetermined by thealtimeter where a decision must be made to either

continue the landing or execute a missed approach


58/89

ILS CATEGORIES:

There are three categories of ILS which support similarly

named categories of operation. Information below is based on ICAO, FAA andJAA;[3] certain states may have filed differences.

Category I (CAT I) A precision instrument approach and landing with a

decision height not lower than 200 feet (61 m) above touchdown zone

elevation and with either a visibility not less than 800 meters or 2400 ft or a

runway visual range not less than 550 meters (1,800 ft) on a runway with

touchdown zone and runway centerline lighting .

Category II (CAT II) A precision instrument approach and landing with a

decision height lower than 200 feet (61 m) above touchdown zone elevation

but not lower than 100 feet (30 m), and a runway visual range not less than

350 meters (1,150 ft) (ICAO and FAA) or 300 meters (980 ft) (JAA).[3]

Category III (CAT III) is subdivided into three sections:

Category III A A precision instrument approach and landing with:

a) a decision height lower than 100 feet (30 m) above touchdown zone

elevation, or no decision height (alert height); and

b) a runway visual range not less than 200 meters (660 ft).

Category III B A precision instrument approach and landing with:

a) a decision height lower than 50 feet (15 m) above touchdown zone

elevation, or no decision height (alert height); and


59/89

b) a runway visual range less than 200 meters (660 ft) but not less than 50

meters (160 ft) (ICAO and FAA) or 75 meters (246 ft) (JAA).[3]

Category III C A precision instrument approach and landing with no

decision height and no runway visual range limitations. This category is not

yet in operation anywhere in the world, as it requires guidance to taxi in zero

visibility as well. "Category III C" is not mentioned in EU-OPS. Category III B is

currently the best available system.[3]

In contrast to other operations, CAT III weather minima do not provide

sufficient visual references to allow a manual landing to be made. The minima

only permit the pilot to decide if the aircraft will land in the touchdown zone

(basically CAT III A) and to ensure safety during rollout (basically CAT III B).

Therefore an automatic landing system is mandatory to perform Category III

operations. Its reliability must be sufficient to control the aircraft to

touchdown in CAT III A operations and through rollout to a safe taxi speed in

CAT III B (and CAT III C when authorized).[3] However, special approval hasbeen granted to some operators for hand-flown Cat III approaches using

"heads up display" (HUD) guidance which provides the pilot with an image

viewed through the windshield with eyes focused at infinity, of necessary

electronic guidance to land the airplane with no true outside visual references.

FAA Order 8400.13D allows for special authorization of CAT I ILS

approaches to a decision height of 150 feet (46 m) above touchdown, and a

runway visual range as low as 1,400 feet (430 m).[4] The aircraft and crew

must be approved for CAT II operations, and a heads-up display in CAT II or

III mode must be used to the decision height. CAT II/III missed approach

criteria applies.[4]


60/89

In Canada, the required RVR for carrying out a Cat I approach is 1600 ft,

except for certain operators meeting the requirements of Operations

Specification 019, 303 or 503[5] in which case the required RVR may be

reduced to 1200 ft


61/89

RADAR

Radar is basically a means for gathering information about distantobjects called targets by sending electromagnetic waves at them and

analyzing the returns called the echoes.

RADAR is an acronym coined by the US Navy from the words RadioDetection And Ranging.

Radar can be used to see through the conditions such asdarkness,haze,snow,fog etc. which eyes cant do. In addition it can be

used to measure the range of the object which probably is the most

important application of RADAR.


62/89

BASIC PRINCIPLE OF RADAR

The basic principle of radar is illustrated in Fig. 2.1. A

transmitter generates an electromagnetic signal (such as a short pulse of sine

wave) that is radiated into space by an antenna. A portion of the transmitted

energy is intercepted by the target and reradiated in many directions. The

reradiation directed back towards the radar is collected by the radar antenna,

which delivers it to a receiver. There it is processed to detect the presence of

the target and determine its location. A single antenna is usually used on a

time-shared basis for both transmitting and receiving when the radar

waveform is a repetitive series of pulses. The range, or distance, to a target is

found by measuring the time it takes for the radar signal to travel to the

target and return back to the radar. The target's location in angle can be

found from the direction the narrow-beamwidth radar antenna points when

the received echo signal is of maximum amplitude. If the target is in motion,


63/89

there is a shift in the frequency of the echo signal due to the doppler effect.

This frequency shift is proportional to the velocity of the target relative to the

radar (also called the radial velocity). The doppler frequency shift is widely

used in radar as the basis for separating desired moving targets from fixed

(unwanted) "clutter" echoes reflected from the natural environment such as

land, sea, or rain. Radar can also provide information about the nature of the

target being observed. The term radar is a contraction of the words radio

detection and ranging. The name reflects the importance placed by the early

workers in this field on the need for a device to detect the presence of a

target and to measure its range. Although modern radar can extract moreinformation from a target's echo signal than its range, the measurement of

range is still one of its most important functions. There are no competitive

techniques that can accurately measure long ranges in both clear and adverse

weather as well as can radar.

Maximum range of radar depends upon:-

Peak transmission power (4 th root)


64/89

Minimum detectable signal (MDS)

Antenna Gain

Radar cross section of the target

Atmospheric attenuation

The range Rto a target is determined by the time Tr it takes the radar signal

to travel to the target and back.

R= cTr/2

Classification of RADARs:-

Based on role of targets:-

1)Primary Radar2)Secondary Radar

Based on Waveform:

CW Radar:Can detect moving targets and its velocity

CW FM Radar:Can detect range using FM Signals.

Pulsed Radar: Uses pulse modulated micro wave signals for detecting

range and velocity of targets.


65/89

CLASSIFICATION OF RADARS

Based on services provided:

Search Radar:Also known as Surveillance Radar. This radar normally uses a

continuously rotating antenna to acquire targets in a large volume of space.

Tracking Radar:It can give an accurate angular position, range and radial

velocity of targets with precision. If a radar is purely used for tracking, a

search radar must also be co-located for first acquiring the target.

PRIMARY RADAR( FREQUENCY RANE OF ASR IF 2.7-2.9

MHz)

In Primary RADARs cooperation of targets are not required for detection

and to find the range, the position, the relative velocity of the target. In

other words, the role of the target is said to be passive and is limited onlyto reflect the Radar signals back to the Radar. Most of the radars used for

the air traffic control like the ASR, ARSR, PAR, etc belong to the group of

Primary radars

Advantages: The following are the main advantages of a primary

radar:-

a. It works independently i.e. the active cooperation of the target is

not required.

b. It engages several targets simultaneously and is not likely to get

saturated.


66/89

c. The electronic system is comparatively simpler, requires only one

set of transmitter and receiver.

Disadvantages: The following are the main disadvantages of a

primary radar:-

a) The efficiency of a primary Radar is poor because the echo signalsdepend on the target size, material etc.

SECONDARY RADAR

Here the active cooperation of targets is very much required for finding the

range and other details of the targets. Hence the role of the targets is said

to be active. Secondary Radar system basically consists of two principal


67/89

components namely the 'Interrogator' which is ground based and the

'Transponder' which is carried on the targets. Each of these components

consists of a set of pulse transmitter and receiver. The Interrogator radiates

pulses which when received by a corresponding transponder on a target

will initiate a

reply from that transponder. These replies are then collected by the

interrogator to extract information about the targets.

THE MSSR WORKS IN L BAND OF FREQUENCY. IT INTERROGATES

AT 1030 MHz AND THE TRANSPONDER REPLY AT 1090 MHz.


68/89

MSSR INTERROGATION


69/89

1)The interrogator transmits a pair of pulses at 1030MHz.

2)Each pulse has the same duration, shape andamplitude.

3)Their spacing distinguishes various modes ofinterrogation P2 pulse use is for control.

Transponder Reply


70/89

1)F1 and F2 are always present (framing pulses)2)The 12 Binary data pulses in four groups of 3 bits: A, B,C, D

3)Special codes: 7500=Hijack, 7600=Com Fail, 7700= Emergency

reply),indicating heights.

4) .

Advantages: The main advantages of secondary radars are as follows:

a. Considerable range increase is possible as the radar transmission

has to travel the distance between the target & the radar only once.

b. It allows low powers to be used to get a given performance.


71/89

c. Echo is no longer dependent on the target size, material etc.

d. Since there is a frequency difference between the transponder &

the interrogator, received signals are totally free from permanent target

echoes.

e. By suitable coding, some useful information can be conveyed from

the target to the ground station.

Disadvantages: The main disadvantages of secondary radars are: a. It

can be used for friendly targets only. b. The system operation depends

upon the equipment on the target remaining serviceable. c. All secondary

radars are liable to be saturated.

RADAR APPLICATIONS

Air Traffic Control

Aircraft navigation


72/89

Maritime navigation Meteorological applications Space applications

Military application Law enforcement application

RADARS USED IN ATC:-

Airport Surveillance Radar (ASR)

Air Route Surveillance Radar (ARSR)

Airport Surface movement Detection Equipment (ASDE)

Precision Approach Radar (PAR)

Mono-pulse Secondary Surveillance Radar (MSSR)


73/89

ASMGCS

(FREQUENCY:- 9170 GHz & 9438 GHz)

ASMGCS stands for Advanced Surface Movement and

Guidance Control System. This system is used for ground

surveillance and monitoring. ASMGCS covers a 5 NM radius. Its main function

is to monitor all the flights arriving, departing and all objects present on

ground within the radius. The ASMGCS processes real time images,

called videos. Thus, all moving objects on and around the runway are

monitored through It is a system at airports having a surveillance

infrastructure consisting of a Non-Cooperative Surveillance (e.g. SMR,

Microwave Sensors, Optical Sensors etc) and Cooperative Surveillance

(e.g. Multilateration systems).

MODULES OF ASMGCS:

1)Modulator2)Receiver3)Mother Board & Power Supply4)Radar Signal Distributor(RSD)5) ssssTC3:- IT is used to set or change parameters such as forward power

etc.

6)VP3


74/89

7)Motor Controller8)Waveguide Switch: It is used to bypass the signal by rotataing the switch.9)Diplexer10) Attenuator11) Directional Couplor:- it is used to measure power.12) Twisted waver:-It is used to isolate the signal (ensure one direction of

waves).

System Realization

_ HARDWARE COMPONENTS (including andData Flow)

_Operational system

_Supporting system

_ Traffic Analysis & Replay

_ System Management and Control

_ SOFTWARE COMPONENTS (including mapping of software on hardware)


75/89

Operational System: Data Flow

Operational System: HW Components

_ Radar Data Processor (RDP)

_ Processes the radar returns and generates a digitized radar image and plots.


76/89

_ Interface Processor (IP)

_ Processes the external interface messages.

_ Converts these messages to A-SMGCS internal format.

_ Central Tracking Processor (CTP)

_ Surveillance data processing (SMR plots, Approach, MLAT, ADS-B data),

identification and alerting.

_ Display Processor (DP)

_ Executes HMI applications (present traffic picture and handle user inputs).

Supporting System: Data Flow Recording, Replay & Traffic

Analysis


77/89

Recording/Replay/Analysis:

HW Components:-

_ Recording Replay Processor (RRP)

_records data in files, each covering one minute

_recording 24/7 on a disk array (RAID 5)

_(if needed) can replay data on a replay/analysis working position

_collects statistical information (in .csv file every 24h)

_ Display Processor (DP)

_Executes HMI applications for Traffic Display and for Replay control.

System Management


78/89

System Management: HW Components

_ Control and Monitoring System Processor (CMSP)

_ collects and presents system status

_ provides remote control of system components

_ Display Processor

_ Executes HMI application for CMS (web base interface)

_ Control commands are routed through the CMSP


79/89

SOFTWARE COMPONENTS

Software Components (including mapping of SW on type of processor):

1)CMS Processor (CMSP):-receives status information from applications and

subsystems.

_monitors both the technical status (including errors/warnings) and the

operational status of the system

(whether the subsystem is fully operational or not)

_provides for a (web-based) user interface (to stop and started system

components via the CMS application)

2)Central Processor (CTP):-

_multi-sensor target trackingsing radar, ADS-B and MLAT measurements.

_track identification and identification guarding._orocessing of runway and taxiway closures

_Processing of meteorological settings (including visibility and runway

configuration).

3)Display Processor (DP):-

_used for data presentation and human interaction with A3000 system.

roles defined: Controller, Apron controller, Supervisor, Replay, Maintenance, or

Monitor

Interface Processor (IP):-


80/89

converts data, represented in external data formats, into HITT internal data

formats and vice versa.

_Radar Data Processor (RDP):-

calculates a video threshold (fromnclutter measurements in the digitized

video).

_ uses masks and the video threshold information to generate hits.

_ creates digitised video (from hits)

_ creates plots (from the digitised video).

_ plots are a simplified image with an echo position, strength, length, width

and orientation.

_ controls the Video Processor.

_Recording and Replay Processor (RRP):-

records the A3000 internal data streams (sensor data, track data, plan data).

_ time-stampes and stores data on disk for later retrieval in files that cover 1-

minute time intervals, i.e. each minute of data is stored in a separate file.

_replays recorded data.

_collects track events for (later) statistical analyses (e.g. line crossings and area

entry or exit).


81/89

GAGAN


82/89

The GPS aided geo augmented navigation or GPS and geo-

augmented navigation system (GAGAN) is a planned implementation of aregionalsatellite-based augmentation system(SBAS) by theIndian

government. It is a system to improve the accuracy of aGNSS receiverby

providing reference signals.[2] TheAAIs efforts towards implementation of

operational SBAS can be viewed as the first step towards introduction of

modern communication, navigation, surveillance/Air Traffic

Managementsystem over Indian airspace.[3]

The project involves establishment of 15 Indian Reference Stations, three

Indian Navigation Land Uplink Stations, three Indian Mission Control Centers

and installation of all associated software and communication links. GAGAN is

planned to get into operation by the year 2014. It will be able to help pilots

to navigate in the Indian airspace by an accuracy of 3 m. This will be helpful
http://en.wikipedia.org/wiki/Satellite-based_augmentation_systemhttp://en.wikipedia.org/wiki/Satellite-based_augmentation_systemhttp://en.wikipedia.org/wiki/Satellite-based_augmentation_systemhttp://en.wikipedia.org/wiki/Government_of_Indiahttp://en.wikipedia.org/wiki/Government_of_Indiahttp://en.wikipedia.org/wiki/Government_of_Indiahttp://en.wikipedia.org/wiki/Government_of_Indiahttp://en.wikipedia.org/wiki/Global_navigation_satellite_systemhttp://en.wikipedia.org/wiki/Global_navigation_satellite_systemhttp://en.wikipedia.org/wiki/Global_navigation_satellite_systemhttp://en.wikipedia.org/wiki/GPS-aided_geo-augmented_navigation#cite_note-ASM-2http://en.wikipedia.org/wiki/GPS-aided_geo-augmented_navigation#cite_note-ASM-2http://en.wikipedia.org/wiki/Airports_Authority_of_Indiahttp://en.wikipedia.org/wiki/Airports_Authority_of_Indiahttp://en.wikipedia.org/wiki/Airports_Authority_of_Indiahttp://en.wikipedia.org/wiki/Air_Traffic_Managementhttp://en.wikipedia.org/wiki/Air_Traffic_Managementhttp://en.wikipedia.org/wiki/Air_Traffic_Managementhttp://en.wikipedia.org/wiki/GPS-aided_geo-augmented_navigation#cite_note-mycoordinates.org-3http://en.wikipedia.org/wiki/GPS-aided_geo-augmented_navigation#cite_note-mycoordinates.org-3http://en.wikipedia.org/wiki/GPS-aided_geo-augmented_navigation#cite_note-mycoordinates.org-3http://en.wikipedia.org/wiki/GPS-aided_geo-augmented_navigation#cite_note-mycoordinates.org-3http://en.wikipedia.org/wiki/Air_Traffic_Managementhttp://en.wikipedia.org/wiki/Air_Traffic_Managementhttp://en.wikipedia.org/wiki/Airports_Authority_of_Indiahttp://en.wikipedia.org/wiki/GPS-aided_geo-augmented_navigation#cite_note-ASM-2http://en.wikipedia.org/wiki/Global_navigation_satellite_systemhttp://en.wikipedia.org/wiki/Government_of_Indiahttp://en.wikipedia.org/wiki/Government_of_Indiahttp://en.wikipedia.org/wiki/Satellite-based_augmentation_system


83/89

for landing aircraft in tough weather and terrain like Mangalore airport and

Leh.

GAGAN after its final operational phase completion, will be compatible

with other SBAS systems such as theWide Area Augmentation

System(WAAS), theEuropean Geostationary Navigation Overlay

Service (EGNOS) and theMulti-functional Satellite Augmentation

System(MSAS) and will provide seamless air navigation service across

regional boundaries. While the ground segment consists of eight reference

stations and a master control centre, which will have sub systems such as data

communication network,SBAS correction and verification system, operations

and maintenance system, performance monitoring display and payload

simulator, Indian land uplinking stations will have dish antenna assembly. The

space segment will consist of one geo-navigation transponder.

FLIGHT MANANEMENT:-

A flight-management system based on GAGAN will then be poised to save

operators time and money by managing climb, descent and engine

performance profiles. The FMS will improve the efficiency and flexibility by
http://en.wikipedia.org/wiki/Wide_Area_Augmentation_Systemhttp://en.wikipedia.org/wiki/Wide_Area_Augmentation_Systemhttp://en.wikipedia.org/wiki/Wide_Area_Augmentation_Systemhttp://en.wikipedia.org/wiki/Wide_Area_Augmentation_Systemhttp://en.wikipedia.org/wiki/European_Geostationary_Navigation_Overlay_Servicehttp://en.wikipedia.org/wiki/European_Geostationary_Navigation_Overlay_Servicehttp://en.wikipedia.org/wiki/European_Geostationary_Navigation_Overlay_Servicehttp://en.wikipedia.org/wiki/Multi-functional_Satellite_Augmentation_Systemhttp://en.wikipedia.org/wiki/Multi-functional_Satellite_Augmentation_Systemhttp://en.wikipedia.org/wiki/Multi-functional_Satellite_Augmentation_Systemhttp://en.wikipedia.org/wiki/Multi-functional_Satellite_Augmentation_Systemhttp://en.wikipedia.org/wiki/SBAShttp://en.wikipedia.org/wiki/SBAShttp://en.wikipedia.org/wiki/SBAShttp://en.wikipedia.org/wiki/Multi-functional_Satellite_Augmentation_Systemhttp://en.wikipedia.org/wiki/Multi-functional_Satellite_Augmentation_Systemhttp://en.wikipedia.org/wiki/European_Geostationary_Navigation_Overlay_Servicehttp://en.wikipedia.org/wiki/European_Geostationary_Navigation_Overlay_Servicehttp://en.wikipedia.org/wiki/Wide_Area_Augmentation_Systemhttp://en.wikipedia.org/wiki/Wide_Area_Augmentation_System


84/89

increasing the use of operator-preferred trajectories. It will improve airport

and airspace access in all weather conditions, and the ability to meet the

environmental and obstacle clearance constraints. It will also enhance

reliability and reduce delays by defining more precise terminal area

procedures that feature parallel routes and environmentally optimised

airspace corridors.

GAGAN will increase safety by using a three-diemensional approach operationwith course guidance to the runway, which will reduce the risk of controlled

flight into terrain i.e., an accident whereby an airworthy aircraft, under pilot

control, inadvertently flies into terrain, an obstacle, or water.

GAGAN will also offer high position accuracies over a wide geographical arealike the Indian airspace. These positions accuracies will be simultaneously

available to 80 civilian and more than 200 non-civilian airports and airfields

and will facilitate an increase in the number of airports to 500 as planned.

These position accuracies can be further enhanced with ground basedaugmentation system.


85/89

VOLMET

VOLMET, or meteorological information for aircraft in

flight, is a worldwide network of radio stations that

broadcastTAF,SIGMET andMETARreports onshortwavefrequencies, and in

some countries onVHF too. Reports are sent inupper sidebandmode, using

automated voice transmissions.

Pilots on international routes, such asNorth Atlantic Tracks, use these

transmissions to avoid storms and turbulence, and to determine which

procedures to use for descent, approach, and landing.

The VOLMET network divides the world into specific regions, and

individual VOLMET stations in each region broadcast weather reports for

specific groups of air terminals in their region at specific times, coordinating

their transmission schedules so as not to interfere with one another.

Schedules are determined in intervals of five minutes, with one VOLMET

station in each region broadcasting reports for a fixed list of cities in each

interval. These schedules repeat every hour.

SELCAL
http://en.wikipedia.org/wiki/Radio_networkhttp://en.wikipedia.org/wiki/Terminal_Aerodrome_Forecasthttp://en.wikipedia.org/wiki/Terminal_Aerodrome_Forecasthttp://en.wikipedia.org/wiki/Terminal_Aerodrome_Forecasthttp://en.wikipedia.org/wiki/SIGMEThttp://en.wikipedia.org/wiki/SIGMEThttp://en.wikipedia.org/wiki/METARhttp://en.wikipedia.org/wiki/METARhttp://en.wikipedia.org/wiki/METARhttp://en.wikipedia.org/wiki/Shortwavehttp://en.wikipedia.org/wiki/Shortwavehttp://en.wikipedia.org/wiki/Shortwavehttp://en.wikipedia.org/wiki/VHFhttp://en.wikipedia.org/wiki/VHFhttp://en.wikipedia.org/wiki/Single-sideband_modulationhttp://en.wikipedia.org/wiki/Single-sideband_modulationhttp://en.wikipedia.org/wiki/Single-sideband_modulationhttp://en.wikipedia.org/wiki/North_Atlantic_Trackshttp://en.wikipedia.org/wiki/North_Atlantic_Trackshttp://en.wikipedia.org/wiki/North_Atlantic_Trackshttp://en.wikipedia.org/wiki/North_Atlantic_Trackshttp://en.wikipedia.org/wiki/Single-sideband_modulationhttp://en.wikipedia.org/wiki/VHFhttp://en.wikipedia.org/wiki/Shortwavehttp://en.wikipedia.org/wiki/METARhttp://en.wikipedia.org/wiki/SIGMEThttp://en.wikipedia.org/wiki/Terminal_Aerodrome_Forecasthttp://en.wikipedia.org/wiki/Radio_network


86/89

Selcal, or Selective Calling as it is more correctly known, is

an automatic recognition system that is operated by a two tone signal. The

equipment is connected to the HF radios on aircraft and monitors for a call

even when the squelch is turned up, and the pilots can hear nothing. This

enables the pilots to have some aural peace when crossing the Atlantic or

other oceans as HF radio can be very noisy. Selcals are made up of a four

letter code and when heard have a distinctive bing-bong sound. As a flight

enters the Oceanic FIR, a Selcal check is made the signal activates the on

board Selcal receiver which alerts the pilots with a flashing warning light and

an audible alarm.

Selcals are issued to airlines by the ASRI (Aviation Spectrum Resources

Inc) in USA, and with a total of only 10920 available codes, duplications are

possible. This problem is overcome by allocating duplicate codes to aircraft

operating in different parts of the world, so in theory they should never be

working on the same frequency. If however, duplicate Selcals appear on the

same frequency the problem is generally resolved by moving one of the

flights to another frequency.

The Selcal is made up of two pair of tones, the first pair being

transmitted for approximately 1 second, with the second pair transmitted for

the same duration following a 0.2 second pause. The individual tone

frequencies are designated by letters A - S excluding the letters "I" and "O". A

typical Selcal code is AB-CD, which indicates that the frequencies designated

by letters "A" and "B" would sent followed by the frequencies designated by

letters "C" and "D". Duplicate letters are not permitted in either pair, since

simultaneous transmission of two tones of the same frequency would not be


87/89

distinguishable by the aircrafts Selcal decoder. Also, the same tone is nor

permitted to be used in both the first and second pair.

Most aircraft crossing oceans are fitted with Selcal equipment and

normally the code allocated stays with that aircraft unless it sold and changes

owner.

Frequency TableCode Frequency

A 312.6HZ

B 346.7HZ

C 384.6HZ

D 426.6HZ

E 473.2HZ

F 524.8HZ

G 582.1HZ

H 645.7HZ

J 716.1HZ

K 794.3HZ

L 881.0HZ

M 977.2HZ


88/89

P 1083.2HZ

Q 1202.3HZ

R 1333.5HZ

S 1479.1HZ


89/89

Documents

Airports Authority of India - Copy - Copy - Copy