AVIONICS REPORT

ON

A STUDY ON COMMUNICATION SYSTEMS OF AIRCRAFT,

SUBMARINES AND SHIPS OF INDIA, PAKISTAN AND CHINA

BATCH NO:1

VENKATA GIRI RAJ.S 13L254

VIJAYA SANKAR. N. R 13L255

ASICK. G 14L432

MOHAMMED FAYIJ 14L438

SAYEETH IMRAN 14L445

BACHELOR OF ENGINEERING

ELECTRONICS AND COMMUNICATION ENGINEERING

October 2015

PSG COLLEGE OF TECHNOLOGY

(Autonomous Institution)

COIMBATORE 641004

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PSG COLLEGE OF TECHNOLOGY

(Autonomous Institution)

COIMBATORE 641004

A STUDY ON COMMUNICATION SYSTEMS OF AIRCRAFT,

SUBMARINES AND SHIPS OF INDIA, PAKISTAN AND CHINA

Bona fide record of work done by

BATCH NO:1

VENKATA GIRI RAJ.S 13L254

VIJAYA SANKAR. N. R 13L255

ASICK. G 14L432

MOHAMMED FAYIJ 14L438

SAYEETH IMRAN 14L445

Dissertation submitted in partial fulfillment of the requirements for the degree of

BACHELOR OF ENGINEERING

ELECTRONICS AND COMMUNICATION ENGINEERING

Of Anna University

October 2015

............... ....

M.Ramasubramniam Dr. S. Subha Rani

Faculty guide Head of the Department

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ACKNOWLEDGEMENT

I would like to extend my sincere thanks to Dr. R. RUDHRAMOORTHY, Principal, PSG

College of Technology, for his kind patronage.

I am indebted to Dr. S. SUBHA RANI, Professor and Head of the Department of Electronics and

Communication Engineering, for her continued support and motivation.

I would like to express my gratitude to Dr.P. VISALAKSHI, Program coordinator, my technical

report guide Mr. K.R. RADHAKRISHNAN, Assistant Professor Department of Electronics and

Communication Engineering, for their constant motivation, direction and guidance throughout the

entire course of our technical report.

I am grateful to the support extended by my class advisor Mrs. PRABHAVATHI, Associative

Professor, Department of Electronics and Communication Engineering.

I thank all the staff members of the Department of Electronics and Communication Engineering

for their support.

Last but not the least I thank the Almighty and my family members who have been a guiding light

in all our endeavors.

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TABLE OF CONTENTS

INTRODUCTION................................................................................................................... 7

History of Military communications .................................................................................................................... 7

Military communications equipment ................................................................................................................... 8

Forms of signaling .............................................................................................................................................. 10 Military hand and arm signals ............................................................................................................................. 10 Morse code ............................................................................................................................................................. 10 Radio communications .......................................................................................................................................... 11 Wireless telegraphy ............................................................................................................................................... 12

COMMUNICATIONS SYSTEM ........................................................................................ 13

Based on media ................................................................................................................................................... 13 Optical communication systems ........................................................................................................................... 13 Radio communication systems ............................................................................................................................. 14 Power line communication systems ..................................................................................................................... 14

Based on Technology .......................................................................................................................................... 15 Duplex Communication Systems ......................................................................................................................... 15

Based on Applied Area ....................................................................................................................................... 15 Tactical communications system .......................................................................................................................... 15 Emergency communication system ...................................................................................................................... 15 Automatic call distributor .................................................................................................................................... 16 Voice Communication Control System ............................................................................................................... 16

COMMUNICATION SYSTEMS USED IN AIRCRAFTS............................................... 16

ITU radio spectrum allocations .......................................................................................................................... 17

Aircraft Communications Addressing and Reporting System (ACARS) .......................................................... 18

Via satellite ......................................................................................................................................................... 19

VHF Digital Link ................................................................................................................................................ 20

VHF Digital Link Mode 2 (VDL-2) .................................................................................................................... 21

COMMUNICATION SYSTEMS USED IN SUBMARINES ........................................... 21

COMMUNICATION SYSTEMS USED IN SHIPS .......................................................... 25

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COMMUNICATION SYSTEMS IN CHINESE DEFENSE ............................................ 27

Aircrafts.............................................................................................................................................................. 27 Y-8X Aircraft ......................................................................................................................................................... 27 KJ-2000 Main ring ................................................................................................................................................ 28 Y-8J Cub ................................................................................................................................................................ 29 Y-8T Cub/High New 4........................................................................................................................................... 30

Submarines ......................................................................................................................................................... 31 Quantum communication ..................................................................................................................................... 31

Battleships and Carriers .................................................................................................................................... 33 Type 815G Electronic Intelligence (ELINT) ship ............................................................................................... 33

COMMUNICATION SYSTEMS IN INDIAN NAVY ...................................................... 34

Communications ................................................................................................................................................. 34

Radiotelephone ................................................................................................................................................... 34

Wireless Link Interface Communications ......................................................................................................... 36

Communication Systems-Indian Navy ............................................................................................................... 37

Sonar and Radars ............................................................................................................................................... 39

Indigenous Sonars and Radars with Indian Navy ............................................................................................. 40

Consolidated Antennas and Sensors .................................................................................................................. 42

MARITIME COMMUNICATION SYSTEM ................................................................... 43

Architecture ........................................................................................................................................................ 43

Topology ............................................................................................................................................................. 43

Future proof ....................................................................................................................................................... 44

Gate X ................................................................................................................................................................. 44

Coastal Radio Services (CR) .............................................................................................................................. 44 Maritime Communication System for Coastal Radio Services (CR) ................................................................ 44

Coastal Surveillance Solutions (CSS) ................................................................................................................. 45 Maritime Communication System for Coastal Surveillance Solutions (CSS) .................................................. 45

Port Communication Solutions (PCS)................................................................................................................ 45 The Port - Gateway to the World ......................................................................................................................... 45

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COMMUNICATION SYSTEMS IN PAKISTAN NAVY ................................................ 46

Pakistan Selects ASELSAN Systems for Navy Fleet Tanker Defense ............................................................... 46

Remote Controlled Stabilized Naval Gun System (STOP) ................................................................................ 47

Communication Switching System (CSS) .......................................................................................................... 47

Communications for All Naval Platforms .......................................................................................................... 47

Navy-Wide Communications System ................................................................................................................. 48

Integrated Communications System (ICS) ........................................................................................................ 49

Maritime IP Networking .................................................................................................................................... 50

Communications System for Submarines .......................................................................................................... 50

Aircraft Carriers ................................................................................................................................................ 51

Secure Radio-communications ........................................................................................................................... 51

The R&SM3SR Series4100 radios ................................................................................................................... 52

Data Encryption ................................................................................................................................................. 53

COMPARISON AND FUTURE INFERENCES ON INDIAN DEFENSE ..................... 53

Indian Military Strategic Thinking, Military Doctrine ..................................................................................... 55

Indian Army Expansion Plans ........................................................................................................................... 58

Indian Air Force Expansion Plans ..................................................................................................................... 60

Indian Air Bases ................................................................................................................................................. 61

Indian Naval Expansion Plans ........................................................................................................................... 62

Pakistan Army VS The Indian Army ................................................................................................................. 65

Pakistan Navy Comparison with Indian Navy ................................................................................................... 66

Pakistan Air Force Comparison with Indian Air Force .................................................................................... 67

RESULT................................................................................................................................. 69

BIBLIOGRAPHY ................................................................................................................. 70

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TABLE OF FIGURES

FIGURE 1 SOVIET PLATOON RADIO SYSTEM ..................................................................................................... 9

FIGURE 2 INTERNATIONAL MORSE CODE SYSTEM ...................................................................................... 10

FIGURE 3 RADIO DIAL ............................................................................................................................................ 11

FIGURE 4 GERMAN HELIOGRAPH ....................................................................................................................... 12

FIGURE 5 SIGNAL LAMP USED TO SEND MORSE CODE ................................................................................. 12

FIGURE 6 GENERAL BLOCK DIAGRAM OF COMMUNICATION SYSTEMS ................................................. 13

FIGURE 7 SIGNAL PROCESSING IN COMMUNICATION .................................................................................. 14

FIGURE 8 COMUNICATION CAPABILITIES OF SUBMARINE OPERATIONS ................................................ 22

FIGURE 9 Y-8X AIRCRAFT ..................................................................................................................................... 27

FIGURE 10 KJ-2000 MAIN RING ............................................................................................................................. 28

FIGURE 11 Y-8J CUB ................................................................................................................................................ 29

FIGURE 12 Y-8T CUB/HIGH NEW 4 ....................................................................................................................... 30

FIGURE 13 KILO-CLASS SUBMARINE ................................................................................................................. 32

FIGURE 14 TYPE 815G SPY SHIPS ......................................................................................................................... 33

FIGURE 15 CONTROL SYSTEM PICTURE ............................................................................................................ 46

FIGURE 16 OUTLINE OF NAVY COMMS ............................................................................................................. 47

FIGURE 17 SUBMARINE ......................................................................................................................................... 50

FIGURE 18 AIRCRAFT CARRIER ........................................................................................................................... 51

FIGURE 19 MULTIBAND RADIO ........................................................................................................................... 52

FIGURE 20 THE R&SM3TR MULTIBAND RADIOS .......................................................................................... 52

FIGURE 21 DATA ENCRYPTION ENCODER ........................................................................................................ 53

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Introduction

Military communications or military signals involve all aspects of communications, or

conveyance of information, by armed forces. Military communications span from prehistory to the

present. The earliest military communications were delivered by humans on foot. Later,

communications progressed to visual and audible signals, and then advanced into the electronic

age. Examples for Military Communications include text, audio, facsimile, tactical ground based

communications, terrestrial microwave, tropospheric scatter, naval, satellite communications

systems and equipment, surveillance and signal analysis, encryption and security and direction

finding and jamming.

History of Military communications

The first military communications involved the use of runners or the sending and receiving

of simple signals (sometimes encoded to be unrecognizable). The first distinctive uses of military

communications were called "signals". Modern units specializing in these tactics are usually

designated as "signal corps". The Roman system of military communication (cursus publicus or

cursus vehicularis) is an early example of this. Later, the terms "signals" and "signaler" became

words referring to a highly distinct military occupation dealing with general communications

methods (similar to those in civil use) rather than with weapons.

Present day military forces of an informational society conduct intense and complicated

communicating activities on a daily basis, using modern telecommunications and computing

methods. Only a small portion of these activities are directly related to combat actions. Middle

20th century field systems often required an operator

Modern concepts of network centric warfare (NCW) rely on network oriented methods of

communications and control to make existing forces more effective.

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Military communications equipment

Drums, horns, flags, and riders on horseback were some of the early methods the military

used to send messages over distances. Many modern pieces of military communications equipment

are built to both encrypt and decode transmissions and survive rough treatment in hostile climates.

They use different frequencies to send signals to other radios and to satellites.

Military communications or "comms" are activities, equipment, techniques, and tactics

used by the military in some of the most hostile areas of the earth and in challenging environments

such as battlefields, on land, underwater and also in air. Military comms include command, control

and communications and intelligence and were known as the C3I model before computers were

fully integrated. The U.S. Army expanded the model to C4I when it recognized the vital role played

by automated computer equipment to send and receive large, bulky amounts of data.

The first military communications tool was the communication automobile designed by the

Soviet Union in 1934 to send and receive signals. The signals were encoded to help prevent the

enemy from intercepting and interpreting top secret communications. The advent of distinctive

signals led to the formation of the signal corps, a group specialized in the tactics of military

communications. The signal corps evolved into a distinctive occupation where the signaler became

a highly technical job dealing with all available communications methods including civil ones.

In the modern world, most nations attempt to minimize the risk of war caused by

miscommunication or inadequate communication. As a result, military communication is intense

and complicated, and often motivates the development of advanced technology for remote systems

such as satellites and aircraft, both manned and unmanned, as well as computers. Computers and

their varied applications have revolutionized military comms. Although military communication

can be used to facilitate warfare, it also supports Intelligence gathering and communication

between adversaries, and thus sometimes prevents war.

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Figure 1 Soviet Platoon Radio System

There are six categories of military comms: the alert measurement systems, cryptography,

military radio systems, nuclear command control, the signal corps, and network centric warfare.

The alert measurement systems are various states of alertness or readiness for the armed

forces used around the world during a state of war, act of terrorism or a military attack against a

state. They are known by different acronyms, such as DEFCON, or defense readiness condition,

used by the U.S. Armed Forces.

Cryptography is the study of methods of converting messages into disguised, unreadable

information, unless one knows of the method of decryption. This military comms method ensures

that the messages reach the correct hands. Cryptography is also used to protect digital cash,

signatures, digital rights management, intellectual property rights and secure electronic commerce.

It is also used in computing, telecommunications and infrastructure. Military comms use many

kinds of radios. A few are ACP131, AN/ARC164, AN/ARC5, HWU transmitter, Hall crafters

SX28, SCR197, SCR203 and SCR270 radar.

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Forms of signaling

Military hand and arm signals

Hand and Arm signals are one of the most common forms of communication used by group

of soldiers when a radio silence is in effect or if the soldiers need to remain undetected. Through

the use of these signals military leaders, such as team leaders, squad leaders, platoon leaders, etc...,

are able to keep command and control over their particular element. All new recruits are taught to

use the proper hand and arm signals found in the FM. However, it is not uncommon for units to

adopt and/or create their own signals. These signals ultimately become known as SOP or standard

operating procedure.

Visual signals are any means of communication that require sight and can be used to

transmit prearranged messages rapidly over short distances. This includes the devices and means

used for recognition and identification of friendly forces.

Morse code

Morse code is a method of transmitting text information as a series of on/off tones, lights,

or clicks that can be directly understood by a skilled listener or observer without special equipment.

The International Morse Code encodes the ISO basic Latin alphabet, some extra Latin letters, the

Arabic numerals and a small set of punctuation and procedural signals as standardized sequences

of short and long signals called "dots" and "dashes" or "dits" and "dahs", as in amateur radio

practice.

Figure 2 International Morse code System

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Radio communications

Radio is the radiation (wireless transmission) of electromagnetic energy through space.

The biggest use of radio waves is to carry information, such as sound, by systematically changing

(modulating) some property of the radiated waves, such as their amplitude, frequency, phase, or

pulse width. When radio waves strike an electrical conductor, the oscillating fields induce an

alternating current in the conductor. The information in the waves can be extracted and

transformed back into its original form.

Radio systems need a transmitter to modulate (changes some property of the energy

produced to impress a signal on it, for example using amplitude modulation, angle modulation

(which can be frequency modulation or phase modulation). Radio systems also need an antenna to

convert electric currents into radio waves, and vice versa. An antenna can be used for both

transmitting and receiving. The electrical resonance of tuned circuits in radios allow individual

stations to be selected. The electromagnetic wave is intercepted by a tuned receiving antenna. A

radio receiver receives its input from an antenna and converts it into a form usable for the

consumer, such as sound, pictures, digital data,

Figure 3 Radio Dial

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Wireless telegraphy

Wireless telegraphy is the transmission of electric telegraphy signals wirelessly. It is now

used as a historical term for early radio telegraphy systems which communicated with radio waves,

although when the term originated in the late 1800s it was also used for a variety of other

experimental techniques for communicating telegraphically without wires, such as photoelectric

and induction telegraphy.

Other similar forms of signaling include Flag semaphore, Flag signals, Naval flag

signaling, Signal lamp, Heliograph etc

Figure 4 German Heliograph

Figure 5 Signal lamp Used to send Morse Code

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Communications System

A communications system is a collection of individual networks, transmission

systems, relay and tributary stations, and data terminal equipment capable of inter-connection and

inter-operation to form an single integrated system. The components of a

communications system are compatible, common, has good control response and performs unified

operation. A communications subsystem is a functional unit or operational assembly that is

smaller than the larger assembly under consideration.

Communications system can be classified into different types based on three factors, they

are

Based on media.

Based on technology.

Based on Applied area.

Figure 6-General Block diagram of Communication systems

Based on media

Optical communication systems

An optical communication system is any form of telecommunication that uses light as the

transmission medium. Equipment consists of a transmitter, which encodes a message into an

optical signal, a channel, which carries the signal to its destination, and a receiver, which

reproduces the message from the received optical signal. Fiber-optic communication systems

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transmit information from one place to another by sending light through an optical fiber. The light

forms an electromagnetic carrier wave that is modulated to carry information.

Radio communication systems

A radio communication system is composed of several communications subsystems that

give exterior communications capabilities. A radio communication system comprises a

transmitting conductor in which electrical oscillation or currents are produced and which is

arranged to cause such currents or oscillations to be propagated through the free space medium

from one point to another remote therefrom and a receiving conductor at such distant point adapted

to be excited by the oscillations or currents propagated from the transmitter.

Figure 7 Signal Processing in Communication

Power line communication systems

Power line communication systems operate by impressing a modulated carrier signal on

power wires. Different types of power line communications use different frequency bands,

depending on the signal transmission characteristics of the power wiring used. Since the power

wiring system was originally intended for transmission of AC power, the power wire circuits have

only a limited ability to carry higher frequencies. The propagation problem is a limiting factor for

each type of power line communications.

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Based on Technology

Duplex Communication Systems

A duplex communication system is a system composed of two connected devices which

can communicate with one another in both directions. Duplex systems are employed in nearly all

communications networks, either to allow for a two-way communication between two connected

devices or to provide a reverse path for the monitoring and remote adjustment of equipment in the

field.

An Antenna is basically a small length of a qwert conductor that is used to radiate or

receive electromagnetic waves. It acts as a conversion device. At the transmitting end it converts

high frequency current into electromagnetic waves. At the receiving end it transforms

electromagnetic waves into electrical signals that is fed into the input of the receiver. Several types

of antenna are used in communication.

Based on Applied Area

Tactical communications system

A tactical communications system is a communications system that

a) is used within, or in direct support of tactical forces,

b) is designed to meet the requirements of changing tactical situations and varying

environmental conditions,

c) provides securable communications, such as voice, data, and video, among mobile

users to facilitate command and control within, and in support of, tactical forces

and

d) usually requires extremely short installation times, usually on the order of hours, in

order to meet the requirements of frequent relocation.

Emergency communication system

An Emergency communication system is any system (computer based) that is organized

for the primary purpose of supporting the two-way communication of emergency messages

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between both individuals and groups. These systems are commonly designed to integrate the cross-

communication of messages between are variety of communication technologies.

Automatic call distributor

An Automatic call distributor (ACD) is a communication system that automatically queues,

assigns and connects callers to handlers. This is used often in customer service ordering by

telephone or coordination services (such as in air traffic control).

Voice Communication Control System

A Voice Communication Control System (VCCS) is essentially an ACD with

characteristics that make it more adapted to use in critical situations i.e. no waiting for dial tone,

or lengthy recorded announcements, radio and telephone lines equally easily connected to,

individual lines immediately accessible etc...

Communication Systems used in Aircrafts

It used to be that a wing wave or rapid tail deflection was all that was needed by the pilot

of an aircraft to acknowledge a visual queue from a person on the ground. The evolution of

electronic communications equipment is almost as dramatic as the evolution of the aircraft.

Traditional aircraft communications are based on analog voice on either a Very High

Frequency (VHF) or High Frequency (HF) radio waves. In the mid-1980s the use of data-based

communications became a reality. Airspace management is transcending into the computer age

and as new requirements evolve and the choice of communications technologies expand,

regulating the worlds air traffic flow can safely become more automated. Aircraft are currently

being equipped with communications technologies that transport data via satellite plus while they

are on the ground; mobile communication and in some cases broadband networks can receive or

broadcast strategic information regarding aircraft situation and even maintenance trends.

Aircraft communications are being expanded; in fact, in recent years a new abbreviation

has surfaced. CNS ATM stands for Communication, Navigation, and Surveillance and Air Traffic

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Management which was created to support modernization of the dated and overload prone Air

Traffic Control system.

Aircraft that are intended to transport passengers are equipped with radios that enable

analog voice communications. This is currently and will be for the foreseeable future the primary

means for pilots to communicate with different entities of the Air Traffic Control (ATC) system.

ITU radio spectrum allocations

The allocation of radio spectrum is defined by the International Telecommunications Union

(ITU) and relates the use of a frequency to a specific service. In the case of civil aviation there are

separate ITU allocations for communications, navigation, and surveillance. Such differentiation

between functions corresponds to the safety requirements for Air Traffic Control. The ITU has

assigned frequencies for use by aircraft analog voice dialogue in parts of the High Frequency

(3-30 MHz) band and in the 118-137 MHz section of the wider Very High Frequency range.

Aircraft can use radios operating in the HF radio band for long-range communications as the

signals are reflected by the ionosphere. Unfortunately, when using HF the link audio quality is

very poor due to this long propagation of the wave. Aircraft can use radios operating in the VHF

band to communicate with other radios in line-of-sight coverage. These signals do not reflect off

the ionosphere or penetrate obstacles such as mountains or buildings. The advantage of VHF over

HF is that the link quality is much better and there is greater reuse of the frequency channel. The

use of the word analog in relation to voice radio communications means that the changes in the

sound of the voice are converted by the transmitter into corresponding variations in the radio signal

and converted back by the receiver.

This analog system is simpler than more recent digitized voice systems that periodically

measure the sound of the voice, convert the sound into a number in a predefined range, and send

the numbers over the radio link. Aircraft VHF analog radios can use channels of varying width

and the minimum width depends on the precision of the technology.

Aircraft have been using VHF radios for the past six decades and advancements in

electronics have enabled the minimum channel width to be reduced from 100 kHz down to 8.33

kHz, which gives an exponential increase to the number of usable frequencies.

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Aircraft Communications Addressing and Reporting System (ACARS)

Aircraft began to be equipped with computers in the 1970s and this led to the development

in 1978 of a data communications system called the Aircraft Communications Addressing and

Reporting System (ACARS).

Aircraft with ACARS can exchange data messages via a network of automated ground

stations incorporating internal computers. Airlines first used the data link system to send

movement reports to the ACARS service processors using the telex formats that operators had

previously used to send those reports. ACARS are widely used today with airborne installations

exceeding 10,000 aircraft.

ACARS units are connected to a VHF radio and in many cases, interfaced with satellite

systems. This type of data communications is sent via conventional VHF radio waves that are

received through a network of ground stations linked via a terrestrial network to a centralized data

link service processor. This is what provides the connection to the ground systems of the users.

Data communications can also be sent via satellite networks but will ultimately link to the

service processor that supports the VHF ACARS service. The function of the service processor is

to route messages automatically between the user aircraft and ground systems, using mostly a fixed

configuration of delivery addresses by message type for downlink messages and by memorizing

the ground station to be used for uplink messages.

The main restriction on the ACARS system is that it uses character codes representing only

printable characters. This limitation applied to all early generation data communications systems.

This did not prevent the ACARS system from becoming the foundation of airline operations

efficiency. However, the development of new radio communications technology and the need to

support air traffic management, calls for newer technologies to be implemented.

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Via satellite

Aircraft have been able to carry out voice and data communications via the Inmarsat

satellites for more than 25 years. Until then, this satellite constellation was intended to provide

communication services to ships. The number of aircraft currently equipped to use Inmarsat has

exceeded 3,500 and is made up of airliners, business jets, and government aircraft.

Four satellites placed in geo-stationary orbit above the equator are centralized over the

Pacific Ocean, Indian Ocean, Atlantic Ocean-East, and Atlantic Ocean-West. This constellation

provides coverage through a global beam between 80 degrees above and below the equator.

The original Inmarsat Aeronautical service provides two modes, circuit mode supporting

voice communications and packet mode supporting always-on data communications.

Aircraft operators use the Inmarsat circuit mode to offer voice service to passengers and

flight deck crew. Aircraft operators use the Inmarsat packet mode, which provides a data rate

approaching that of some home high-speed lines.

The move of aircraft communications from voice to data has motivated some operators of

HF radio ground stations to install HF data link (HFDL) computers that enable the transport of

ACARS data. Manufacturers of aircraft HF radios have added capabilities to support ACARS.

The new HF radios can switch between voice and data mode using the same components,

but they are required to give voice communications precedence over data link. This has a tendency

to limit the HFDL availability. This isnt a commonplace application.

High Frequency radio data link has been found to provide better availability than HF voice

on trans-Polar routes beyond the 80-degree North/South limit of Inmarsat satellite coverage. The

HFDL capacity is only limited by the frequencies available in the HF band. The allocation of HF

frequencies to data link has required a very complex co-ordination process and the system will

quickly reach its limits.

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The addition of data link capability to HF radio is a way for aircraft operators to get

additional use out of the radios they still carry in order to meet ATC rules when most

communications migrate from voice to data.

VHF Digital Link

The term VHF Digital Link was adopted by the International Civil Aviation Organization

(ICAO) Aeronautical Mobile Communications Panel (AMCP), at its first meeting in November

1991, to refer to digital communications carried on the Aeronautical VHF band. The Aeronautical

VHF Band is the section of the Very High Frequency spectrum allocated to Aeronautical Service

by the International Telecommunications Union. It is made up of the following two groupings:

108-118 MHz assigned to the purpose of radio-navigation and 118-137 MHz which is used for

radio-communications.

The plan for VHF band to become a data carrier was proposed in the ICAO Future Air

Navigation Systems (FANS) committee report issued in 1988. The airline community had

recognized the benefits of aircraft data link communications 10 years before the FANS report and

had implemented the VHF version of ACARS.

The ICAO reserved four VHF channels: 136.900, 136.925, 136.950, and 136.975 MHz for

data communications worldwide. This later decision catered for the reservation of frequencies in

order for such data service to be implemented in an environment when the existing aviation VHF

spectrum was considered saturated and congested with existing VHF channels for air traffic analog

voice.

VHF Digital Link (VDL) was put in motion by 1991 through the effort of the Aeronautical

Mobile Communications Panel (AMCP) with a plan to increase the capacity of the VHF band; and

develop a standard for an Aeronautical Telecommunications Network (ATN) data link service

using VHF radio.

The AMCP has developed standards for VDL Modes 1-4 in which the modes provide

different capabilities which currently have political divisions.

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Mode 1 was created with the intent of using analog radios incorporating a device to install

a coded signal on the existing carrier wave. This mode was never carried forward as analog radios

were already viewed as dinosaurs. Further considerations brought about Mode 2 and 3 which

present the position of the FAA wanting to use all new digital radios with a 25 kHz frequency

spacing and the Euro control concept of going with 8.33 kHz frequency spacing.

On air transport aircraft, the communications, navigation, and surveillance functions will

continue to be processed by separate devices:

1. Communications : VHF data radio or a satellite data unit;

2. Surveillance : Mode S transponder; and GNSS data link;

3. Navigation : Global positioning systems and instrument landing systems multi-

mode receivers.

VHF Digital Link Mode 2 (VDL-2)

VHF Digital Link Mode 2 (VDL-2) was conceived in the early 1990s as a method of

providing high-speed data communications to aircraft. From the outset VDL-2 was intended to

support safety critical Air Traffic Control communications. In addition, airline operational data

would also be supported by VDL-2; a service traditionally supplied using ACARS.

Global deployment of VDL-2 is now rapidly gaining acceptance by the airlines and Air

Traffic Control agencies. In the United States, the FAA has been using VDL-2 in the Miami region

with selected airlines prior to a nationwide rollout of the system. In Europe, Euro control has

strongly endorsed the operational benefits of VDL-2. Euro control is offering financial assistance

to help airlines install VDL-2 equipment, reduced route charges will follow for properly outfitted

aircraft, and finally a mandate will be introduced to bring about full compliance, possibly, by the

end of the decade.

Communication Systems used in Submarines

Submarines communicate via multiple, complementary RF systems, covering nearly all

the military communications frequencies. No one communications system or frequency band

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can support all submarine communications requirements. Submarine shipboard communications

systems consist of RF antennas and radio room equipment, both RF transmitters/receivers and

baseband suites. Submarines require a suite of antennas to provide the necessary

communications, navigation, and Identification, Friend or Foe (IFF) capabilities. Submarine

antennas, as compared to surface ship antennas, are unique in design, shape, materials, and

performance due to a submarine's space and weight limitations, extreme environmental

conditions, and stealth considerations. UHF SATCOM provides a relatively high data rate but

requires the submarine to expose a detectable mast-mounted antenna, degrading its primary

attribute - stealth. Conversely, extremely low frequency (ELF) and VLF broadcast

communications provide submarines a high degree of stealth and flexibility in speed and depth,

but are low data rate, submarine-unique and shore-to-submarine only.

The US Navy is investing in new and previously demonstrated techniques for

communicating with submarines at speed and depth for coordinated ASW operations. These

techniques most commonly use either trailing wires or towed buoys for submarine

communications, which impose limitations on the submarine's maneuverability and stealth, and

therefore negatively impact the submarine's ability to fully conduct ASW operations. An

airborne laser which could penetrate shallow water would permit submarine communications

without the restrictions of floating wires or buoys.

Figure 8-Comunication capabilities of submarine operations

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ELF [Extremely Low Frequency 30 Hz - 300 Hz 10,000 Km - 1,000 Km wavelength] -

This is the only band that can penetrate hundreds of meters below the surface of the ocean. The

US Navy transmits ELF messages using a huge antenna in Wisconsin and Michigan created by

several miles of cable on towers in conjunction with the underlying bedrock. This band is used

to send short coded "phonetic letter spelled out" (PLSO) messages to deeply submerged

submarines that are trailing long antenna wires. The communication is only one way; therefore,

it is used primarily for prearranged signals or to direct the submarine to come closer to the

surface for faster communications. Environmental factors do not have a strong influence on

changing the signal and therefore it is quite reliable

VLF [Very low frequency 3 kHz - 30 kHz 100 Km - 10 Km] This band can penetrate

several meters below seawater and can transmit much more information than ELF, therefore it

is useful for submarine communications when the submarine cannot surface, but can come close

to the surface. It can be affected by salinity gradients in the ocean, but these usually do not

present problems for near-surface submarines. There are natural sources of VLF radiation, but

in general, like ELF, it is not strongly influenced by changes in environmental conditions

therefore it is useful for reliable global communications. The transmission antennas need to be

large, therefore it is primarily used for one-way communications from shore-based command

centers to surface ships and submarines. It can also be used to broadcast to several satellites at

once, which can in turn relay messages to the surface. The Navy's VLF systems serve as a back-

up for global communication use during hostilities when nuclear explosions may disrupt higher

frequencies or satellites are destroyed by enemy actions. VLF is also used for aircraft and vessel

navigation beacons and for transmitting standard frequencies and time signals.

HF [High frequency 3 MHz - 30 MHz 100 m - 10 m] - The Navy makes extensive use of

this band for communications. It is also used for long range ("over-the-horizon") radar. Due to

the sky wave transmission mode, HF radiation can travel great distances, sometimes to the other

side of the earth. Due to its versatility and large coverage area, this is a very crowded band and

the military can only use a few frequency regions scattered throughout this band. The most

efficient transmissions require fairly large antennas; therefore, it is most useful when at least one

of the stations is on shore. The antenna size limits its use on aircraft. It cannot be used for satellite

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communications since it is reflected by the ionosphere. Many of the former uses of HF by the

Navy are now being taken over by satellite communication systems. However, we expect that

the Navy will continue to use HF for quite some time in the future. The primary drawback to HF

use is that it is highly susceptible to changes in the ionosphere and therefore several frequencies

must be available for use.

One of the immediate tasks delineated by the Navy in "From the Sea" is to continue the

full integration of SSNs into expeditionary task forces. To be effective units of a Naval Task

Group within a joint, Tailored Forward Element (TFE), submarines must be fully interoperable

with both Naval and Joint communication systems. Submarines must be capable of tailoring on-

board capabilities to optimize their support for the Joint Task Force (JTF) and Naval Component

Commanders.

Coordination between multiple assets such as aircraft, surface ships, and submarines is

critical to an effective ASW campaign. Integration of submarines into an overall ASW effort,

arguably the most effective platform for wide area search and tracking, has traditionally been

hampered by lack of or minimal communications to the submarine while deep.

Submarine communications were once limited to those necessary to communicate mission

support information and the minimal command and control that a submarine previously required.

The Navy continues to implement the principles of Network Centric Warfare, where the

capability of the total force is made greater than the contributions of individual platforms through

networking of sensors, weapons control systems, and information systems.

As submarines continue to conduct a variety of missions to include intelligence collection,

Indications and Warning (I & W), anti-submarine warfare, anti-surface warfare, strike warfare,

and mine warfare, they will have to be an integral part of networked sensors and platforms.

Submarines' future missions will require a revolution in communications connectivity and

supporting bandwidth. The vision is to allow submarines to communicate without the current

restrictions of depth and speed and with sufficient bandwidth to maximize the effectiveness of

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data and intelligence collected by the submarine, such that real-time connectivity and reach-back

is achieved.

The development of these advanced communications has already begun with the

incorporation of Narrowband based systems that are IP architecture based. Following this is

development of a higher data rate antenna and wideband based communications and ultimately

a buoyant cable antenna that allows two-way communications at depth and speed.

Ultimately submerged data exchange and communications capabilities will be a key

enabler for employing off-board vehicles, sensors, and distributed networks of UUVs, sensors

and other payloads.

Communication Systems used in Ships

From the early years of the last century, ships started fitting radio for communicating

distress signals among themselves and with the shore. Radio telegraphy using Morse code was

used in the early part of the twentieth century for marine communication.

Marine communication between ships or with the shore was carried with the help of on

board systems through shore stations and even satellites. While ship-to-ship communication was

brought about by VHF radio, Digital Selective Calling (DSC) came up with digitally remote

control commands to transmit or receive distress alert, urgent or safety calls, or routine priority

messages. DSC controllers can now be integrated with the VHF radio as per SOLAS (Safety of

Life at Sea) convention.

Satellite services, as opposed to terrestrial communication systems, need the help of geo-

stationary satellites for transmitting and receiving signals, where the range of shore stations cannot

reach. These marine communication services are provided by INMARSAT (a commercial

company) and COSPAS SARSAT (a multi-national government funded agency).

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While INMARSAT gives the scope of two way communications, the Corpas Sarsat has a

system that is limited to reception of signals from emergency position and places with no facilities

of two way marine communications, indicating radio beacons (EPIRB).

For international operational requirements, the Global Maritime Distress Safety System

(GMDSS) has divided the world in four sub areas. These are four geographical divisions named

as A1, A2, A3 and A4.

Different radio communication systems are required by the vessel to be carried on board

ships, depending on the area of operation of that particular vessel.

A1 Its about 20- 30 nautical miles from the coast, which is under coverage of at least one VHF

coast radio station in which continuous DSC alerting is available.

Equipment used: A VHF, a DSC and a NAVTEX receiver (a navigational telex for receiving

maritime and meteorological information).

A2 This area notionally should cover 400 nautical miles off shore but in practice it extends up

to 100 nautical miles off shore but this should exclude A1 areas.

Equipment used: A DSC, and radio telephone (MF radio range) plus the equipment required for

A1 areas.

A3 This is the area excluding the A1 & A2 areas. But the coverage is within 70 degrees north

and 70-degree south latitude and is within INMARSAT geostationary satellite range, where

continuous alerting is available.

Equipment used: A high frequency radio and/ or INMARSAT, a system of receiving MSI

(Maritime Safety Information) plus the other remaining systems for A1 and A2 areas.

A4 These are the areas outside sea areas of A1, A2 and A3. These are essentially the Polar

Regions North and South of 70 degree of latitude.

Equipment used: HF radio service plus those required for other areas.

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All oceans are covered by HF marine communication services for which the IMO requires

to have two coast stations per ocean region. Today almost all ships are fitted with satellite terminal

for Ship Security Alerts System (SSAS) and for long range identification and tracking as per

SOLAS requirements.

On distress, Search and Rescue operations from Maritime Rescue Co-ordination centers

are carried out among other methods, with the help of most of these marine navigation tools.

Naturally, the sea has become a lot safer with these gadgets and other important navigation

tools recommended by the IMO and as enshrined in GMDSS

Communication Systems in Chinese Defense

Aircrafts

Y-8X Aircraft

Y-8X is PLAN's first long-range maritime patrol aircraft (range 5,000km). It is equipped

with an American Litton AN/APS-504(V3) surface search radar in an enlarged under nose radome

plus western navigational systems for long range patrols over the sea. The aircraft also carries

optical and IR cameras.

Some Y-8Xs (Y-8XG 9271 & 9291) have been upgraded with a FLIR turret installed

underneath the forward fuselage as well as small bar-shaped antennas on both sides of the forward

fuselage. A canoe shaped fairing plus a couple blade antennas were seen attached to the bottom of

middle and aft fuselage, suggesting the aircraft's ELINT mission has been further enhanced with

possibly a new SAR capability.

Figure 9 Y-8X Aircraft

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KJ-2000 Main ring

The KJ-2000 prototype was based on Russian A-50I airframe but fitted with an indigenous

AEW and a CISR system, including ARINC429 data bus, IFF and datalink. The AEW system,

developed by Nanjing Research Institute of Electronic Technology/14th Institute, is presumably

similar to the Israeli Phalcon system. It was reported that the system can track 60-100 aerial targets

simultaneously with a max range of 470km. The aircraft features a fixed rotodome housing

three AESA antennas in a triangular configuration. As the result a 360 radar coverage can be

achieved.

A SATCOM antenna is installed inside the fairing on top of the forward cabin. Two large

angled ventral fins are attached underneath the tail to compensate the impact of rotodome on

aircraft handling. KJ-2000 is able to patrol in the air for up to 12 hours with a max range of

5,500km. A nose-mounted IFR probe suggests its operations could be further extended with the

tanker support.

Figure 10 KJ-2000 Main ring

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Y-8J Cub

It may feature a Search water 2000 surveillance radar housed in an enlarged, partially dropped nose

radome, a configuration similar to the smaller Britten Norman Defender twin turboprop for ground and

maritime patrol and AEW roles. The Search water 2000 radar has a maximum detection range of 400km.

A total of 100 aerial targets can be tracked simultaneously. Y-8J also has a limited C&C capability. The

control center can direct up to 6 aircraft to intercept enemy aircraft with around 4 display consoles in a

small pressurized cabin. It can also provide target information to surface ships and submarines via datalink.

It was speculated that the aircraft could be used to provide targeting information for long-range anti-ship

missiles, but this has not been confirmed.

This AEW variant is believed to be less capable than the KJ-200 AWACS just entering service

with PLAN but can be viewed as a stop-gap measure. Recent images (December 2014) indicated that a

dorsal SATCOM antenna has been installed. Some were seen having two small windows of unknown

purpose installed underneath the tail.

Figure 11 Y-8J Cub

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Y-8T Cub/High New 4

It has a redesigned real fuselage section with the loading ramp and tail gun turret removed.

The aircraft also features a dorsal fairing aft the wing section which might house a SATCOM

antenna. Multiple communication antenna arrays can be seen planted along the top and bottom of

the fuselage, as well as on the vertical tailfin.

Figure 12 Y-8T Cub/High New 4

Similarly, there are many developments and innovations in Chinese aircraft design and

many other parameters including the technology behind communication being kept up-to-date till

now.

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Submarines

Quantum communication

Due to recent technological breakthrough China has been showing off its new hardware, a

potentially more important military advancement has gone largely unnoticed, Chinese scientists

announced a demonstration of "quantum teleportation" over 16 kilometers (10 miles), creating

what Matthew Luce, a researcher at the Defense Group Inc.'s Center for Intelligence Research and

Analysis, calls secure communications guaranteed by the laws of physics. China is now at the

cutting-edge of military communications, transforming the field of cryptography and spotlighting

a growing communications arms race.

While the People's Liberation Army won't be beaming up objects Star Trek-style anytime

soon, the new technology could greatly enhance its command and control capabilities. Scientists

use machines to manipulate units of light called photons. By changing the photons' quantum states

and creating a new, readable pattern not unlike Morse code, they can pass on simple messages or

encryption codes. A group of researchers from Tsinghua University and the Hefei National

Laboratory for Physical Sciences entangled pairs of photons linking them so changes to one

photon will be instantaneously transferred to the other. Using a high-powered blue laser (the type

China appears to be investing in for its submarine fleet), they then transported the quantum

information farther than anyone had done before, their paper in Nature Photonics claims.

The process is called teleportation, but the information in the message is not actually

moved. Instead, changes to one photon's quantum state will be adopted instantly by the other

something Einstein famously called spooky action at a distance. The result is akin to having two

pieces of paper 10 miles apart, and as a person writes on one paper the message simultaneously

appears on the other.

Theoretically, this method cannot be cracked or intercepted, If the photons in the laser

beam are observed by a third party, the particles themselves will be altered due to a law of physics

called the Heisenberg Uncertainty Principle, which states that measuring a particle alters it. As

such, the sender and receiver would be immediately informed that someone was snooping.

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At the 16km distance tested, China would be able to send these secure messages from its

network of satellites to units on the ground, the choice of a blue laser instead of an infrared one

like the U.S. has been testing was chosen with its growing submarine fleet in mind since blue

lasers penetrate farther underwater. Soon, Chinese satellites could be able to communicate with

submarines without them needing to surface or give away their location by breaking radio silence.

This may sound like science-fiction, but quantum encryption is already used by a few banks and

governments for highly sensitive information on a smaller scale.

Figure 13 Kilo-class submarine

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Battleships and Carriers

Types of ships present in republic of china are classified as follows

1. Aircraft carriers

2. Amphibious warfare ships

3. Destroyers

4. Frigates

5. Corvettes

6. Missile boats, submarine chasers and gunboats

7. Mine countermeasures

8. Fleet replenishment

For example

Type 815G Electronic Intelligence (ELINT) ship

The Type 815G ELINT spy ship will still provide a critical role in Chinese naval and joint

operations. Of particular note are the two sensor domes on the Type 815Gs superstructure; the

large size of those domes indicates high sensitivity to record distant enemy radar emissions,

electronic jamming frequencies and communications signals. Type 815G spy ships will help

Chinese commanders prepare and understand the battlefield.

Figure 14 Type 815G spy ships

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Communication systems in Indian Navy

At sea in war, a naval ship targets the enemy vessels by listening to them through

communication channels by intercepting their messages through wireless radios or seeing them

through radars and sensing them through sonars.

Warship at sea functions like a huge sea creature in respect of a majority of its functions.

For example, there is a need for a ship to see, listen, and communicate; it uses Radars, Sonars and

Communication equipment for these tasks. The overall goal of the warship is to identify and

eliminate the threats arising at sea, thus all the equipment on board a warship is required to function

in unison to achieve this aim. Emphasis in this article would be on Communication equipment,

discussion on technological aspects of Radars and Sonars would be limited to essentials only.

Communications

The first official message from a ship to a shore station, 20 miles away, was sent in 1899,

the first use of radiotelephone between ships was reported in 1916. However, until the installation

of super heterodyne receivers on board ships in 1931, radio communication was considered

unreliable. Radio teletypewriter transmissions between ships were carried out successfully in 1944,

and the first FAX (radio-photo) transmission was that of the surrender document that ended World

War II

Navies use visual, sound, and electrical means for communications. Telecommunication

includes in its ambit transmission, emission, signals, images, sounds, and intelligence information

by visual, oral, wire, radio, or other electronic systems.

Radiotelephone

Ships use radiotelephony because of its ease of operation, directness, and convenience. In

the navy, it is used for communication between ship-to-ship, ship-to-shore, shore-to-ship, air-to-

ship, ship-to-air, air-to-ground, and ground-to-air. The most important use of radiotelephone is in

short-range tactical communication.

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Radio communication has become a specialized field of electronics. Naval ships today have

the ability to utilize ship-to-shore, ship-to-ship, and ship-to-air, communication circuits. Naval

communication systems vary in complexity depending upon their role, compatibility, and

flexibility. Due to scarcity of space on board a ship, the communication equipment is spread across

the ships compartments; however, it is ensured that the sets are capable of operating separately as

well as concurrently. Complex interconnections provide the ability of selectively switching

different configurations.

Radiofrequency bands commonly used for naval communication include, very high

frequency and above, high frequencies, medium frequency, low frequency, very low frequency,

and extremely low-frequency.

Very High Frequency and above (30 MHZ 300 MHZ) are only used for line of sight

communication as ground range is very less. High Frequency, HF (3 MHZ 30 MHZ), has been

used by the navy since WW I. HF is used for point-to-point, ship to shore, ground to air and fleet

broadcast (one way only). Medium Frequency, MF (300 KHZ 3 MHZ), bands in the upper and

lower portions of MF are used by the Navy for ground wave transmission, since the commercial

band generally extends from 535 to 1605 kilohertz. Low Frequency, LF (30 KHZ 300 KHZ),

band has only a very small part of the radio-frequency spectrum. Low-frequency transmitting

installations have large physical size and high construction and maintenance costs. However, Low-

frequency waves are not so seriously affected during periods of ionosphere disturbance when

communications at the high frequencies are disrupted. This makes LF useful in the northern

latitudes. Very Low Frequency, VLF (3 KHZ 30 KHZ) provides a highly reliable path for

communications over and under all oceans and seas of the world. Currently all naval VLF

transmitters are used for fleet communications or navigation. VLF transmission is normally a one-

way transmission, a broadcast, where no reply is required. A VLF broadcast of standard time and

frequency signals provides precision for the operation of single-sideband transmissions,

synchronous cryptographic devices, and decoding devices. It is used as a backup to shortwave

communications black out by nuclear activity, as well as in communications to satellites.

Extremely Low Frequency, ELF (Up to 300 HZ), communications are used by the US Navy to

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send short phonetic letter spelled out (PLSO) messages (one-way communication) from

operating authorities to submarines operating at normal mission speeds and depths. ELF penetrates

ocean depths to several hundred feet with little signal loss.

Wireless Link Interface Communications

The US Navy has already begun the deployment of wireless link interface technology on

board 97 of its ships for maritime interception operations. The wireless system will allow

communication directly with boarding teams several miles away. Interdiction units will be able to

transmit biometric data, scanned documents, digital photos, and emails, back to the ship using the

data link. US navy has successfully tested microwave-based wireless wide-area network (WWAN)

between ships to enable incorporation of Long-Term Evolution (LTE) standard, generally referred

to as 4G LTE. It is a standard for high-speed communications among mobile devices, and transmits

data at around 100 megabits/sec, fast enough to handle images and videos as well as voice and

text. The WWAN would normally augment the existing satellite-based communications. The LTE

network would let sailors on ships receive real-time video streaming from air nodes mounted on

helicopters, which in turn would permit officers to make accurate decisions. Oceus Networks is

the likely provider of the systems.

DCNS has developed SYSmart, a commercial wireless communications and tracking

system. It enables exchange of video, voice, and data wirelessly from anywhere on board a ship

using handheld devices. Internet linked video and infrared cameras and other shipboard sensors

can be accessed by the sailors. The system is built around existing Ethernet systems and other

proprietary wireless networks. It has been successfully tested on French naval ships and is to be

incorporated in the next generation of French submarines in 2017.

Rohde & Schwarz in Europe was commissioned to design and build a navy-wide

communications network encompassing shore stations, corvettes, patrol boats, landing crafts of

many sizes and with diverse applications, coastal mine hunters, and maritime patrol aircraft

(MPA). Tailored voice and data communications solutions have been defined for shipboard

internal communications and external line-of-sight (LOS) and beyond-line-of-sight (BLOS) radio

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communications. A navy-wide military message handling system (MMHS) covers both strategic

and tactical communications. Proprietary applications supplement the STANAG protocols to

include chat and e-mail functionality. In addition, HF and VHF/UHF solutions for IP-based

services have been incorporated. Different subsystems for capabilities such as telephone calls,

announcements, alarms, and internal tactical communications on the ship, message handling, and

radio equipment have been integrated into an overall system. From a single workstation, it would

be possible, to take part in the ships internal communications as well as in external voice & data

communications and to manage & control applications and devices.

The French Navy has also selected Rohde & Schwarz to provide R&SM3SR radio

communications systems for their newest nuclear submarines. The Spanish Navy also decided to

equip their latest tactical submarines with Rohde & Schwarz radio communications systems.

It also provides worldwide communications systems for different kinds of aircraft carriers. The

R&SM3SR Series4400 is used on the newest and biggest aircraft carrier generation that the

United Kingdoms Royal Navy operates.

Vitavox have been providing the worlds largest navies with military communications

equipment since 1933. The audio equipment provided by Vitavox can be used in a variety of

applications, both above and below deck as well as above and below surface.

Communication Systems-Indian Navy

The Indian Navy is using indigenous systems extensively on its warships, some note-

worthy systems already on board warships and scheduled for fitment on ships under production

are manufactured by BEL, they are: -

ATM Based Integrated Shipboard Data Network (AISDN), it is a multi-services shipboard

network designed to converge all voice traffic, real time video and traditional data communications

onto a single broadband infrastructure. It is a flexible, triple redundant, modular and reliable

network supporting multiple services for naval ships. It integrates various equipment and systems

on board namely EW Systems, Radars, Sonars, CAIO (Computer Aided Information

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Organization), Fire Control Systems, and a number of other equipment for Ships Household Data

(SHHD). It integrates all sensors, weapons, and communication services onto one single

broadband network. It provides integrated and simultaneous transmission of voice, video and data.

It has high system capacity and flexibility and uses fiber optic cable as physical medium.

Composite Communication System (CCS) Mk III is a new generation ATM based

communication system that provides ship-to-ship, ship to shore and ship to air communication. It

is designed as a voice and data integrated network providing connectivity between radio equipment

and remote user onboard for accessing and monitoring and control of radio equipment. The system

is highly flexible and can be configured for all classes of ships. CCS Mk III consists of Control &

Monitoring Subsystems (CMS), which controls and monitors the entire network and enables

operation of radios from remote positions with optimum usage of facilities. Its subsystems are: -

MF Subsystem, it has telegraphy communication and monitors maritime distress

frequency.

HF Subsystem, it has long-range communication on voice, telegraphy & teletype (ship-to-

shore and ship-to-ship) and receives broadcast transmissions.

VHF/UHF Subsystem, Medium range communication on voice, telegraphy & teletype

(ship-to-shore and ship-to-air).

RATT Subsystem, it facilitates tele printer & telegraphic communication from a ship via

radio or land / shoreline.

Versatile Communication System (VCS) Mk III is a versatile system designed to provide

internal communication facilities and display of status of various equipment and systems onboard

naval ships. The system is highly flexible and re-configurable and can be configured for all classes

of ships. It provides, integrated data (Status and Control) and Voice communication from a single

position on IVCS, it uses VOIP technology for Voice & Data communication, it interfaces with

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the ATM based integrated data network (AISDN) onboard the ship; it reduces wiring and

interconnections in the system.

Sonar and Radars

The other important sensors on a warship for underwater and above water threat detection

are the Sonar and the Radar. It is not intended to discuss the general technical details of such

systems. However, few of the Sonars and Radars frequently in news are being briefly described

below.

Thales Underwater Systems has developed and produced Sonar 2087. It has been designed

to be a variable depth, towed active and passive Sonar system that performs in conjunction with

Sonar 2050 bow-mounted active sonar on UKs Type 23 frigates. Digital technology in signal

processing and COTS hardware has been used extensively. It is claimed that S2087 will be suitable

for both, littoral environments and Deep Ocean.

Raytheon has developed the AN/SQQ-90 tactical sonar suite for the US Navys DDG 1000-

class multi-mission destroyer. The AN/SQQ-90 comprises of the AN/SQS-61 hull-mounted high-

frequency sonar, AN/SQS-60 hull-mounted mid-frequency sonar, and the AN/SQR-20 multi-

function towed array sonar and handling system.

Atlas Elektronik will supply Active Towed Array Sonar, ATAS to the Indian Navy, which

will equip the Delhi and Talwar class ships. ATAS would be subsequently manufactured in India

under cooperation with BEL.

EdgeTech, has delivered 12 advanced side scan sonar systems (mine warfare) for the Indian

Navy.

Enterprise Air Surveillance Radar (EASR) is a development program for replacement for

the SPS-48 and SPS-49 air surveillance radars currently on board US Navys amphibious ships

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and aircraft carriers by the 2020. Northrop Grumman has been awarded an 18-month contract for

the study of the EASR requirement. The new radar system will utilize technologies from the

AN/TPS-80 Ground /Air Task-Oriented Radar (G/ATOR) program.

EMPAR (European Multifunction Phased Array Radar) is a G-band, multifunction, active

phased array radar being developed by Selex for the Italian Navy and French Navy. Its rotating

antenna at 60 rpm provides continuous surveillance, tracking, and weapons fire control. The

EMPAR radar system will be integrated on the Horizon frigates ordered by Italy and France and

the Italian Navys Conte di Cavour.

Raytheons AN/SPY-5 is an X-band multi-tracking, target-illuminating system for surface

combatants that can simultaneously search, detect, and precisely track multiple surface and air

threats. The SPY-5 is an open architecture, phased-array radar system, providing an advanced self-

defense solution for small and large surface ships operating in the littorals and other maritime

environments. A single radar system consists of three 120-degree beam faces providing full 360-

degree azimuth coverage. The mission capabilities include low-altitude horizon search; focused

volume search; surface search; missile and surface gunfire control; simultaneous threat

illumination; and missile midcourse guidance and terminal homing. It is compatible with all digital

combat management systems, and the radars range, accuracy and beam agility enable the full

performance of the Evolved Sea Sparrow Missile (ESSM). SPY-5s size, weight and overall self-

defense capabilities make it equally well suited for large-deck aircraft carriers and amphibious

assault ships as well as corvettes.

Indigenous Sonars and Radars with Indian Navy

Indigenous Sonars and Radars held by the Indian Navy are manufactured by BEL. Two

important Sonars manufactured by BEL are the Advanced Active cum Passive Integrated Sonar

System (HUMSA NG) and the Integrated Submarine Sonar (USHUS).

HUMSA-NG is an advanced Active cum Passive integrated sonar system to be fitted on a

wide variety of Indian Navy platforms such as the Project 17, Project 15A and Project 28 class

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ships. HUMSA-NG is an advanced version of the existing HUMSA sonar presently fitted on P16,

P15, Ranjit and Talwar Class of ships. The HUMSA (NG) is designed for enhancing the

system performance, reliability, and maintainability. It is capable of detecting, localizing,

classifying and tracking sub-surface targets in both active and passive modes. The system provides

simultaneous long-range detection in active and passive modes. The sonar is capable of

localization and automatic tracking of up to eight targets in both active and passive modes. The

sonar integrates the operation of the UWT and XBT systems. The system is integrated with FCS

systems such as IAC MOD C and CAIO for exchange of relevant information.

Integrated Submarine Sonar (USHUS) is used to detect, localize and classify underwater

submerged and surface targets through passive listening, interception of signals and active

transmissions of acoustics signals. It has both analog and digital external system interface. It is

modular and rugged in design with upgradeable performance features. Its passive sonar has

performed beams in azimuth and in three vertical directions using ASICS. It can auto track six

targets. Its active sonar has CW and LFM modes of transmission with three selective pulse widths,

high source level, low frequency planar transducer array & complex demodulation, replica

correlation for Doppler and range estimation. Its intercept sonar can provide early warning long

range target detection, all round coverage in three bands, FFT, and Spectral processing. The

underwater communication system has multiple mode acoustic communication in dual frequency

to meet NATO and other requirements, voice, telegraph, data, and message modes of operation.

Its obstacle avoidance sonar is a high frequency short range sonar with rectangular transducer array

and its transmission covers three sectors of 30 each.

Some of the indigenous Radars manufactured by BEL, India are: -

L-Band Surveillance Radar, RAWL02 Mk-III, is long-range L band surveillance radar for

detection of air and surface targets. It has a roll and pitch stabilized antenna platform, Synthesizer

controlled transmitter with TWT amplifier, state of art video extractor track management system

based on COTs technology, low noise receiver combined with split pulse and matched dynamic

range compression, ECCM capability and a range of 270 Km.

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3D Surveillance Radar, REVATHI, is a state-of-the-art, S-band, Track-While-Scan (TWS)

radar designed to effectively play the role of a medium range surveillance radar mounted on a

stabilized platform for detection of air and surface targets. It has ECCM features, integrated IFF

Mk XI, stabilization against roll & pitch, and remote transmission of data of tracks & plots over

LAN for interface with external systems.

Active & Passive Radar for Navigation & Attack (APARNA), is designed to detect surface

targets, furnish target data to fire control computer for missile firing at these targets in the

autonomous mode from the ship. The radar system is provided with two transmittersreceiver

channels i.e. the first or main channel and the second or navigational channel. The two channels

differ in transmitter peak power, pulse width etc.

Consolidated Antennas and Sensors

Communication technology developments to provide ever-increasing requirements of

multiple bands and bandwidths, foresee a need for large rotating antennas. These pose several

problems on board warships like space availability, electromagnetic interference and increase in

ships radar signature. The trend is tilting towards development of single unit consolidating

antennas and sensors. Thales Netherlands is developing its integrated sensor and communications

suite, which will house radio and data-link communication systems, radar and electro-optical

subsystems and IFF in a single unit.

The US Navy has awarded 18 contracts to develop integration and management

technology for radio frequency radar and communications functions. The objective of the

advanced multifunction radio frequency concept is the integration of radar, electronic warfare and

communications into a common set of apparatus with signal and data processing, signal generation

and display hardware.

Thus from the above it can be appreciated that the field of sensors for utilization on a

warship is an ever expanding one, with new features and capabilities adapted from the commercial

world being added practically every hour. To say the least, the features and capabilities of various

warship sensors by end of this decade are going to be phenomenal.

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Maritime Communication System

Our maritime communication systems are land-based and support ship-to-land, land-to-

land and ship-to-ship communication. The joint radio and telephone infrastructure enables fast,

safety-critical communication between all different parties involved in MDA. This infrastructure

is managed from designated communication centers. Our systems use the latest and best

technology, and are designed for flexibility: this allows service providers and their organizations

to evolve and strengthen their role in the future of maritime communication.

The MCS 3020 is a combined voice and data switch specifically designed for the needs of

maritime coastal communications. The MCS 3020 uses the proven VCS 3020X application

software and the latest peripheral hardware for interfaces and operator positions.

The MCS is available in various editions the so called "MCS Family" especially designed

to fulfil all individual customer needs in their different surroundings. These include Coastal Radio

Service (CR), Coastal Surveillance Solutions (CSS), Rescue Coordination Centers (MRCC),

Vessel Traffic Services (VTS) and Port Communication Solutions (PCS).

Architecture

The architecture of the MCS 3020 combines optimal performance with low-risk

communication, and is based on a legacy of proven systems unrivalled in safety and reliability.

The MCS 3020 integrates voice communication for radio and telephone, maritime applications

and sensor information in one unique system. It features unlimited conferencing capabilities, as

well as access to all communication channels for any operator, regardless of the system load at any

time and location.

Topology

The MCS 3020 architecture supports hierarchical connectivity for communication

resources and centers. All critical components of the system are duplicated to ensure the

availability of communication paths. The decentralized and modular MCS 3020 provides full

scalability without requiring software changes. So the solution is suited to both small and large

systems, whether a simple port or harbor communication solution, a communication system for

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VTS centers, a special fully GMDSS-compliant communication system for MRCC, a large coastal

radio system or an extensive communication system for coastal surveillance.

Future proof

The MCS 3020 undergoes constant development. This means, for example, we can already

integrate state of the art communication technologies like VoIP and ROIP (Radio over IP). This

guaranties each customer a solution that is customized perfectly to the infrastructure available

within their existing environment.

Gate X

Meet the new member of the MCS 3020 family: "gate X". This slim module forms the core

switch for smaller applications, such as a port communication system. Despite its size, it uses the

same software and hardware as the very biggest systems on the market, and offers the same

functionality. So MCS 3020 with gate X is the first truly scalable system that has no functional

limitations: you can create any system size required simply by stacking gate X modules.

Coastal Radio Services (CR)

Maritime Communication System for Coastal Radio Services (CR)

Shore to ship, ship to ship, ship to shore and ship to telephone

Due to the dec