SEMINAR REPORT

On

RADAR STEALTH TECHNOLOGY

Submitted in partial fulfillment of the

requirements for the award of the degree of

Bachelor in Technology

Submitted by:

PRAGATI GARG

B.Tech (ECE)- 2014-2018

ID-BTBTE14517

Submitted to:

Mr. Pardeep Lamba

(Asst. Professor)

URJA MANDIR

(DEPARTMENT OF ELECTRONICS AND COMMUNICATION ENGINEERING)

BANSTHALI VIDYAPITH,

BANSTHALI, TONK

RAJASTHAN (304022)

i

CERTIFICATE

This is to certify that the project entitled, “RADAR STEALTH TECHNOLOGY" submitted

by "Pragati Garg" in partial fulfillment of the requirements for the award of "Bachelor in

Technology" in "Electronics and Communication" at the "Banasthali University" is an

authentic work carried out by her under my supervision and guidance.

Date: 24-Sept-2016

Pardeep Lamba

(Asst. Professor, Banasthali University)

ii

DECLARATION

I hereby declare that this report was entirely my own work and that any additional sources of

information have been duly cited.

I hereby declare that any internet sources, published or unpublished works from which I have

quoted or drawn reference have been reference fully in the text and in the contents list. I

understand that failure to do this will result in failure of this report due to Plagiarism.

Signature of the Student:

Place: Banasthali Vidyapith

Date: 24-Sept-2016

iii

PREFACE

The purpose of this report is to look into the development in “COUNTER STEALTH

RADAR” contrary to stealth aircraft which remained unanswered by conventional radars for

decades. Radar Stealth Technology is based on the principle of reflection and absorption that

makes the objects’ observability lower. A ‘Stealth’ vehicle will generally have been designed

from the motive to reduce RCS (RADAR Cross Section) of Aircrafts i.e. RADAR signature

of Aircrafts. Stealth Technology is based on the principle of reflection and absorption that

makes the object stealthy. It also gives the principle of operation of latest RADAR – quantum

RADAR and LIDAR. It compares stealth and anti-stealth technology. Consequently shows

the future vulnerability of stealth aircraft.

iv

ACKNOWLEDGEMENT

I wish to take this opportunity to express my sincere and deep sense of respect to our

teachers, for making us available all the required assistance, support and inspiration to carry

out this proposed topic in the institute. I would like to express my heartiest thanks to our

HOD ma’am, Dr. Ritu Vijay for providing us with all necessary infrastructure and thereby

giving us freedom to carry out the proposed topic. I am also thankful to our guide Mr.

Pardeep Lamba for their constant motivation and for standing all through the completion of

proposed topic. Their technical guidance, expertise and immense help have largely

contributed to the success of this topic.

At the last but not least, I am thankful to my parents, who had encouraged & inspired me with

their blessings. 

v

CONTENTS

S.NO. NAME OF THE TOPIC PAGE NO.

CERTIFICATE (i)

DECLARATION (ii)

PREFACE (iii)

ACKNOWLEDGEMENT (iv)

01 INTRODUCTION 5

02 HISTORY 5

03 RADAR 6

04 RADAR CROSS SECTION 7

05 RADAR STEALTH TECHNOLOGY 7

06 VEHICLE SHAPE 7

07 COATING AND RAMs 8

08 STEALTH HELICOPTERS 9

09 ADVANTAGES AND DISADVANTAGES 10

10 PROPOSED ADVANCEMENTS 11

11 INDIA’s STEP TOWARDS STEALTH 12

12 FUTURE SCOPE OF STEALTH 12

13 CONCLUSION 13

14 REFERENCES 14

vi

INTRODUCTION

Stealth technology also known as LOT (Low Observability Technology) is a technologies

which covers a range of techniques used with aircraft, ships and missiles, in order to make

them less visible (ideally invisible) to radar, infrared and other detection methods. From the

late years of World War II to today's computer enabled design changes, stealth has been a

major factor in the improvement of reconnaissance and attack aircraft. The term "stealth", is

thought to have been coined in 1966 by Charles E. "Chuck" Myers, combat pilot and later an

exec at Lockheed. When we think of stealth today, immediately images of the B-2 bomber or

the F-117A Nighthawk fighter comes to mind. In simple terms, stealth technology allows an

aircraft to be partially invisible to Radar or any other means of detection. This doesn't allow

the aircraft to be fully invisible on radar. Stealth technology cannot make the aircraft invisible

to enemy or friendly radar. All it can do is to reduce the detection range or an aircraft. This is

similar to the camouflage tactics used by soldiers in jungle warfare. Unless the soldier comes

near you, you can't see him. Though this gives a clear and safe striking distance for the

aircraft, there is still a threat from radar systems, which can detect stealth aircraft. Stealth

technology is expanded into each of those areas which seek to detect the aircraft, ships &

missiles. Thus it is essential to develop visual, infrared acoustic and radar stealth. However

many countries have announced that they have developed counter-stealth techniques that

allow them to negate stealth. F-117A NIGHT HAWK FIGHTER

‘Radar Stealth Technology’ is used to prevent the detection of aircrafts or planes from radar

systems.

HISTORY

During World War I, the Germans experimented with the

use of Cellon, a transparent covering material, in an attempt

to reduce the visibility of military aircraft. Single examples

of the Fokker E.III Eindecker fighter monoplane, the

Albatross C.I two-seat observation biplane, and the Link-

Hofmann R.I prototype heavy bomber were covered

with Cellon. But, Cellon was found to be quickly degraded both by sunlight and in-flight

temperature

vii

Fig 1 F117 NIGHTHAWK- First Aircraft based on RADAR Stealth

Technology

changes so the attempt to make transparent aircraft was not proceeded with.

In 1916, the British modified a small SS class airship for the purpose of night-time

reconnaissance over German lines on the Western Front. Fitted with a silenced engine and a

black gas bag, the craft was both invisible and inaudible from the ground but several night-

time flights over German-held territory produced little useful intelligence and the idea was

dropped.

In 1960, the first stealth technology development program was initiated by USAF, by

reducing the radar-cross-section of a Ryan Q-2C Firebee drone. This was achieved through

specially designed screens over the air intake, radar-absorbent material on the fuselage and a

special radar-absorbing paint. The success of Have Blue led the Air Force to create the Senior

Trend program which developed the F-117.

RADAR

RADAR is abbreviated as Radio detection and ranging which is one of the most useful

technologies in the present day warfare. This is used to launch the missiles based on the

target and also counter attack the missile launched by other countries. The idea is for the radar

antenna to send out a burst of radio energy, which is then reflected back by any object it

happens to encounter. The radar antenna measures the time it takes for the reflection to

arrive, and with that information can tell how far away the object is.

The metal body of an airplane is very good at reflecting radar signals, and this makes it easy

to find and track airplanes with radar equipment. The time for the reception of the transmitted

signal to reach the transmitter cum receiver can be effectively used to calculate the distance

of the target from the transmitter.

Radar basically works on two major principles.

1. ECHO: Echo can be considered as a wave bouncing off a surface and coming back to the

source. The time for the reception of the transmitted signal to reach the transmitter cum

receiver can be effectively used to calculate the distance of the target from the transmitter.

2. The Doppler Shift: This being the second principle of the radar. This property on applied to

radar used to determine the speed of the object. The frequency of the reflected wave can be

the same, greater or lower than the transmitted radio wave, if the reflected wave frequency is

less then this means that the target is moving away from the transmitter and if higher then

viii

moving close to the transmitter and if constant then the target is not moving like a helicopter

hovering at a point. This can be used to predict the speeds of the target too.

RADAR CROSS SECTION (RCS)

Radar cross section is the measure of a target's ability to reflect radar signals in the direction

of the radar receiver, i.e. it is a measure of the ratio of backscatter power per steradian (unit

solid angle) in the direction of the radar (from the target) to the power density that is

intercepted by the target. The RCS of a target can be viewed

as a comparison of the strength of the reflected signal from a

target to the reflected signal from a perfectly smooth sphere

of cross sectional area of 1 m2.

RADAR STEALTH TECHNOLOGY

There are two broad aspects of RCS minimization techniques:

One falls under the effort to restructure the frame, and covers the geometric design

considerations that are taken into account when aiming for a low RCS.

The other principle is referred to as "radar absorbent materials" and is concerned with the

materials that help to reduce the reflectivity of the airframe, as well as the structures that will

support these materials and integrate them into the airframe often referred to as "Radar-

absorbent structures".

VEHICLE SHAPE

The stealth designer's mission starts with the

same words as the physician's Hippocratic Oath:

"First, does no harm." The prime most concern

being that of the aircraft's the possibility of

designing aircraft in such a manner as to

reduce their radar cross-section was

recognized in the late 1930s, when the first radar

tracking systems were employed, and it has been

ix

Fig 2 RADAR CROSS SECTION (RCS)

Fig 3 Geometrical shape of Aircraft

known since at least the 1960s that aircraft shape makes a significant difference in

detectability. The Avro Vulcan, a British bomber of the 1960s, had a remarkably small

appearance on radar despite its large size, and occasionally disappeared from radar screens

entirely. It is now known that it had a fortuitously stealthy shape apart from the vertical

element of the tail. On the other hand, the Tupolev 95Russian long range bomber (NATO

reporting name 'Bear') appeared especially well on radar. It is now known that propellers and

jet turbine blades produce a bright radar image; the Bear had four pairs of large (5.6 meter

diameter) contra-rotating propellers. Another important factor is the internal construction.

Behind the skin of some aircraft are structures known as re-entrant triangles. Radar waves

penetrating the skin of the aircraft get trapped in these structures, bouncing off the internal

faces and losing energy. This approach was first used on the F117. The most efficient way to

reflect radar waves back to the transmitting radar is with orthogonal metal plates, forming a

corner reflector consisting of either a dihedral (two plates) or a trihedral (three orthogonal

plates). This configuration occurs in the tail of a conventional aircraft, where the vertical and

horizontal components of the tail are set at right angles. Stealth aircraft such as the F-117 use

a different arrangement, tilting the tail surfaces to reduce corner reflections formed between

them. A more radical approach is to eliminate the tail completely, as in the B-2 Spirit.

COATINGS AND ABSORBERS RAMs (Radar Absorbing Materials)

Radar-absorbing materials (RAMs) are used to dissipate the energy of the radar wave so to

prevent the reception of a reflected signal by an antenna. Usually, the dissipation process

converts the radio frequency (RF) energy to a negligible quantity of heat. RAMs are one of

four ways of reducing the radar cross-section of an object,

which is a measure of the reflection of radar waves by an

object. A larger radar cross-section (RCS) of an object

corresponds to a longer detection range and a higher

signal-to-noise ratio for the observing radar operator. A

747 would have a huge RCS, whereas a bumblebee would

have an insignificant RCS. Other ways of reducing RCS

include passive cancellation, incorporating an echo source

which by design cancels another echo source for a certain

frequency and angle, active cancellation, incorporating a

sensor and emitter which cooperate to radiate waves which interfere with incident radar

waves, and by geometric shaping and design modifications. Only the last will be discussed,

as the former two are rather impractical and are less dependent on material or process

x

Fig 4 Radar absorbing materials

properties. Dielectric and magnetic RAMs are the two main types (along with various

combinations of these) of RAMs in current operational use; these will be explored in further

detail as we go along.

Types of RAMs:

1. IRON BALL PAINT

2. FOAM ABSORBER

3. JAUMANN ABSORBER

Iron ball paint absorber:

One of the most commonly known types of RAM is iron ball paint. It contains tiny spheres

coated with carbonyl iron or ferrite. Radar waves induce molecular oscillations from the

alternating magnetic field in this paint, which leads to conversion of the radar energy into

heat. The heat is then transferred to the aircraft and dissipated. The iron particles in the paint

are obtained by decomposition of iron pentacarbonyl and may contain traces

of carbon, oxygen, and nitrogen.

Foam absorber:

Foam absorber is used as lining of anechoic chambers for electromagnetic radiation

measurements. This material typically consists of a fireproofed urethane foam loaded with

conductive carbon black [carbonyl iron spherical particles, and crystalline graphite particles]

in mixtures between 0.05% and 0.1% (by weight in finished product), and cut into square

pyramids with dimensions set specific to the wavelengths of interest.

Jaumann absorber:

A Jaumann absorber or Jaumann layer is a radar-absorbent substance. When first introduced

in 1943, the Jaumann layer consisted of two equally spaced reflective surfaces and a

conductive ground plane. One can think of it as a generalized, multilayered Salisbury screen,

as the principles are similar.

xi

STEALTH HELICOPTERS

Stealth helicopters are helicopters that incorporate stealth technology to avoid detection. In

recent years, designs for blades have emerged that can significantly reduce noise, which is a

major issue for clandestine use of helicopters. A raid on the compound of Osama bin Laden

on May 2, 2012 utilized what appeared to be two Sikorsky UH-60 Black Hawks, heavily

modified for quieter operations and employing stealth technology to be less visible to radar.

Attack on Bin Laden Used Stealthy Helicopter That Had Been a Secret - MASS MEDIA

Sikorsky UH-60 Black Hawks 22.

Fig 5 Sikorsky UH-60 Black Hawks 22 Helicopter – Used by the Americans to enter into the Pakistan and kill OSAMA BIN LADEN successfully.

ADVANTAGES AND DISADVANTAGES OF STEALTH TECHNOLOGY

ADVANTAGES:

1. A smaller number of stealth vehicles may replace fleet of conventional attacks vehicles

with the same or increased combat efficiency. Possibly resulting in longer term savings in the

military budget.

2. A Stealth vehicles strike capability may deter potential enemies from taking action and

keep them in constant fear of strikes, since they can never know if the attack vehicles are

already underway.

xii

3. The production of a stealth combat vehicles design may force an opponent to pursue the

same aim, possibly resulting in significant weakening of the economically inferior party.

4. Stationing stealth vehicles in a friendly country is a powerful diplomatic gesture as stealth

vehicles incorporate high technology and military secrets.

5. Decreasing causality rates of the pilots and crew members.

DISADVANTAGES:

1. Stealth aircraft cannot fly as fast or is not maneuverable like conventional aircraft. The F-

22 and the aircraft of its category proved this wrong up to an extent.

2. The stealth aircraft can carry only reduced amount of payload. As most of the payload is

carried internally in a stealth aircraft to reduce the radar signature, weapons can only occupy

a less amount of space internally.

3. The biggest of all disadvantages that it faces is its sheer cost. Stealth aircraft literally costs

its weight in gold. Fighters in service and in development for the USAF like the B-2 ($2

billion), F-117 ($70 million) and the F-22 ($100 million) are the costliest planes in the world.

4. Another problem with incorporating "stealth" technology into an aircraft is a wing shape

that does not provide the optimum amount of lift. The resulting increase in drag reduces flight

performance.

PROPOSED ADVANCEMENTS

Stealth technology advances that change stealth technology weapons are currently under

development. These weapons take the idea of stealth to a whole new level. When these

technologies hit the battlefield, they are certain to change the way military operations are

conducted.

Hypersonic: The idea of travelling 20 times the speed of sound (Mach 20) to avoid detection

is a concept that has been studied since the 1970s. Currently under research by DARPA, this

technology would also allow the U.S. military to be anywhere in the world in under an hour.

Though travelling at such speed provides a series of benefits, it also poses some pretty serious

questions, two of which are in thermodynamics and aerodynamics. Travelling at mach 20

creates a huge amount of heat, heat that could melt the aircraft itself. It is also very difficult to

control an aircraft at that speed. In the field of aerodynamics, scientists have been studying

the possibility of adding stabilizers to provide for better control.

xiii

DDG-1000 Zumwalt Class destroyer: The U.S. Navy Battle cruiser proves that stealth

technology is not just for aircraft and people. This technology can also be applied to marine

craft. The Zumwalt was designed for near–shore operations, but has weapon systems for

undersea attacks, anti-ship weapons, and long-range missiles. Not only does the Zumwalt

boast an impressive array of weapons, but the stealth technology used in its construction

gives the ship “very low radar, infrared, and acoustic signatures.”

INDIA’s STEP TOWARDS STEALTH

The Indian administration is also making serious attempts to bring home the stealth

technology. The two aircrafts with stealth are: The HAL Light Combat Helicopter (LCH): It

is a multirole combat helicopter being developed in India by Hindustan Aeronautics Limited

(HAL) for use by the Indian Air Force and the Indian Army. According to reports, the LCH

features a digital camouflage system. The first prototype of LCH completed its first ground

run on 4 February 2010. HAL has a firm order to deliver 65 LCH to the IAF and 114 to the

Army. DRDO AURA: AURA is an autonomous unmanned combat air vehicle (UCAV),

being developed by the DRDO for the Indian Air Force. The design work on the UCAV is to

be carried out by Aeronautical Development Agency (ADA). Details of the project are

classified. The AURA will be stealth UCAV, capable of releasing missiles, bombs and

precision-guided munitions. The programme is in its project definition stage. The design is in

line with what former DRDO chief controller for Aeronautics said in 2007, that India's

combat drone would be a stealthy flying-wing concept aircraft with internal weapons and a

turbofan engine. The UCAV's design is similar to Northrop Grumman's B-2 Spirit.

FUTURE SCOPE OF STEALTH TECHNOLOGY

Stealth technology is clearly the future of air combat. In the future, as air defence systems

grow more accurate and deadly, stealth technology can be a factor for a decisive by a country

over the other. In the future, stealth technology will not only be incorporated in fighters and

bombers but also in ships, helicopters, tanks and transport planes. These are evident from the

RAH66 "Comanche" and the Sea Shadow ship. Ever since the Wright brothers flew the first

powered flight, the advancements in this particular field of technology have seen staggering

heights. Stealth technology is just one of the advancements that we have seen. In due course

of time we can see many improvements in the field of military aviation which would one-day

even make stealth technology obsolete.

xiv

CONCLUSION

The Detection and Stealth Technology has improved significantly more advanced in the last

fifty years or so. This trend is likely to continue as these two oppose each other. Till date

stealth aircraft have been used in several low and moderate intensity conflicts, including

operation Desert Storm. Operation Allied Force and the 2003 invasion of Iraq and kill Osama

Bin Laden in Abbottabad, Pakistan. In all cases they were employed to strike high value

targets which were either out of range of conventional aircraft or which were too heavily

defended for conventional aircraft to strike without a high risk of loss. In addition, because

The stealth aircraft aren't going to be dodging surface to air missiles and anti-aircraft artillery

over the target they can aim more carefully and thus are more likely to hit the high value

targets early in the campaign (or even for it) ,Before other aircraft had the opportunity to

degrade the opposing air defense. However, given the increasing prevalence of excellent

Russion-bilt Surface -to-air missile (SAM) system on the open market, stealth aircraft are

likely to be very important in a high intensity conflict in order to gain and maintain air

supremacy. Stealth technology .in future, would be required for clearing the way for deeper

strikes , which conventional aircraft would find very difficult .For example ,China license-

builds a wide range of SAM systems in quantity and would be able to heavily defend

important strategic and tactical targets in the event of some kind of conflict .Even if anti-

radiation weapons are used in an attempt to destroy the SAM radars of such systems, these

SAMs are capable of shooting down weapons fired against them. The surprise of a stealth

attack may become the only reasonable way of making a safe corridor for conventional

bombers. It would then be possible for the less-stealth force with superior weaponry to

suppress the remaining systems and gain air superiority. The development and the

deployment of the Visby's- the first commissioned Stealth ships has raised new threats in the

maritime boundaries. The sudden appearance of sea clutters on the radar at a region may be

these ships. The plasma stealth technology raises new hopes of engineering brilliance. As

plasma is said to absorb all electromagnetic radiation the development of a counter stealth

technology to such a mechanism will be a strenuous task. Well to conclude the current

scenario appears something similar to the cold war both sides are accumulating weapons to

counter each other and each side can be termed as "Stealth Technology" and the other as

"Anti-Stealth Technology". It's an arm race except it isn't between specific countries. "It's a

fight between Technologies".

xv

REFRENCES

Websites:

1. http://en.wikipedia.org/wiki/Stealth_technology

2. http://science.howstuffworks.com

3. http://www.espionageinfo.com/Sp-Te/Stealth-Technology.html

Journals:

[1] Research Inventy: International Journal Of Engineering And Science Vol.3, Issue 12

(December 2013), pp 15-19, 2010

[2] V.K. Saxena, Stealth and Counter-stealth Some Emerging Thoughts and Continuing

Debates, Journal of Defence Studies, pp 19-28, 2012

[3] S. VASS, Stealth technology deployed on the battlefield, AARMS, pp 257–269, 2000

xvi