radar bullet seminar report - baixardoc

Landmine Detection using RADAR BULLET2014-2015

CHAPTER 1

INTRODUCTION

Radar bullet is a relatively new discovery that was invented in the US. It was

developed by International Research Centre for Telecommunications-Transmission and

RADAR (IRCTR). It is used for detecting land mines. And this discovery finds a very

important prospect as about 139 countries signed a treaty in favor of banning anti-

personal mines. This treaty was signed during the second week of March 1999 in

Ottawa Canada.

Anti -personal mines claims seventy new victims every day. This weapon is

particularly cruel on children whose bodies being smaller and closer to the blast. Are

more likely to sustain serious injury. The severe disabilities and psychological trauma

that follow the blast mean these children will have to be looked after for many year.

A child injured at the age of ten will need about 25 artificial limbs during their

life time. The cost is at 3000, a huge sum to pay in countries where people earn as little

as $10 a month between 1979 and 19960, the red cross fitted over 70,000 amputees with

artificial limbs. And the landmines problem is still growing. Therefore considering these

factors the discovery of radar bullet is really a big boost to our world as we launches

into the 21't century.

The countries known to have severe landmine problems are Afghanistan,

Bosnia, Cambodia, Ethiopia, Vietnam, Iraq, Kuwait, Laos, Egypt, Eritrea, Chevalier,

China. Unfortunately India, Pakistan, Srilanka, Myanmar are in the list of less mine

affected countries besides other 100 countries.

Dept of ECE, VIT


CHAPTER 2

LAND MINE

The purpose of a landmine is to disable, immobilize or kill. It is an explosive

device activated either by a person or vehicle or by command detonated by electric wire

or radio signals. Most land mines are laid on just below the surface of ground and are

activated by pressure or trip-wire. Usually most of the landmines will contain many

metallic parts, which can be made use of in their detection.

Anti-personal mines claims 70 new victims every day. This weapon is

particularly cruel on children whose bodies being smaller and closer to the blast are

more likely to sustain serious injury. The severe disabilities and psychological traumas

that follow the blast- means these children will have to be looked after for many years.

Fig 2.1: Anti-Personnel Landmine

Fig 2.2:Anti-Tank Landmine

Dept of ECE, VIT


Landmines In this discussion we deal with buried anti-tank (AT) and anti-

personnel (AP) landmines which require close approach or contact to activate. AT mines

range from about 15 to 35 cm in size. They are typically buried up to 40cm deep, but

they can also be deployed on the surface of a road to block a column of machinery. AP

mines range from about 5 to 15cm in size. AT mines which are designed to impede the

progress of destroy vehicles and AP mines which are designed to kill and maim people

A child injured at the age of 10 will need about 25 critical limbs during there life

time. This cost in 3000 Dollars a huge sum to pay in countries where people earn as

little as 10 dollar a month. . Between 1979 of 1996 the red crores fitted over 70,000

Amputees with critical limbs and the land mine problem in still growing. There for

considering these factors the discovery of radar bullet is really a big boost to our world

as we launches to 21st century.

Dept of ECE, VIT


CHAPTER 3

PRINCIPLES USED TO DETECT LANDMINES

1. Metal detection

2. Explosive detection

3.1. Metal Detection

Essentially the two most common components of landmines are metals and

explosives. Manufactured mines have casting made from a variety of materials

including wood, metals, Plastic metal or other synthetic materials. From the detection

standpoint, metal is the easier component to detect.

Fig 3.1: Metal Detection

Metal detectors (commonly referred to as mine detectors) are now capable of

signaling the presence of minute piece of metal. However some mines are metal free on

certain virtually non-metal. These non-metals challenge the capacity of current metal

detectors.

4.2. Explosive Detection

The explosives are one common ingredient that is found in all mines. Detecting

explosives however is a complicated process. Modem airports have explosive detecters,

which can detect small traces of explosives in suitcases and other containers. Locating

traces or the order of explosives is an open field demands technology that can operate in

Dept of ECE, VIT


an unlimited variety of environmental conditions that are subjected to wind, water and

soil changes and variations.

Explosive detection under field conditions has recently become the preview of

mine detection dogs. A dog’s nose has proven to be a very sophisticated and reliable

sensor, however handling maid detection dog teams and ensuring consistent behaviour

in varied hazard scenarios is a complicated and demanding tasks.

Fig 3.2: Explosive Detection

In all the above said methods mine detection in conducted in close proximity.

That is detection is conducted after going very near to the mine. This method can prove

to be dangerous in many occations. So it is not considered to be the safest method. A

preferred method is to use detection devices that locate land mines at a safe distance

from the deminer. Using detection devices that pinpoint land mines exploded from a

distance either overhead on at ground level in the best possible way to determine the

actual location of individual land mines. Ones the threat is located, that is mines are pin

pointed, we can deactivate it safely. This is where the importance of mine detection

using radar bullet comes.

Dept of ECE, VIT


CHAPTER 4

RADAR BULLET

The radar bullet is a special type of bullet. The main use of radar bullet is to find

landmines without setting foot on the ground. This consists of firing a special bullet in

to the ground from a helicopter, which could pin point buried land mines.

The bullet units a radar pulse as it grounds to a halt. This pulse strikes the mine

and its image gets available on the computer in the helicopter, offering a safe and

efficient way of finding land mines. Landmines In this discussion we deal with buried

anti-tank (AT) and anti-personnel (AP) landmines which require close approach or

contact to activate. AT mines range from about 15 to 35 cm in size. They are typically

buried up to 40cm deep, but they can also be deployed on the surface of a road to block

a column of machinery. AP mines range from about 5 to 15cm in size. AT mines which

are designed to impede the progress of destroy vehicles and AP mines which are

designed to kill and maim people.

Inside the bullet is a metal cylinder, surrounded by a tightly wounded coin of

wire. As the bullet leaves the gun, there is a battery generating a magnetic field in the

cylinder.

Battery bullet casing

Metallic cylinder

Fig 4: Radar Bullet

Dept of ECE, VIT


CHAPTER 5

RADAR PRINCIPLE

Radar is Radio detection and ranging. Radar is a sensor. Radar makes use of

radio waves to detect and locate objects. The purpose is to provide estimates of certain

characteristics of its surroundings most commonly the presence, position and motion of

aircrafts, ships and other vehicles.

Radar operates by transmitting electro magnetic energy into the surroundings

and detecting energy reflected by object. If a narrow beam of this energy is transmitted

by the directive antenna, the direction from which reflections come and hence the

bearing of object may be estimated. .The distance to the reflecting object in estimated

by measuring the period between the transmission of radar pulse and reception of echo.

In radar bullet principle the change of medium by the waves must be taken into

consideration.

Fig 5: Principle of RADAR

Radars have generally from principal parts, the transmitter antenna receiver, and

display. The transmitter will transmit an electro magnetic signal through the antenna,

Dept of ECE, VIT


which will hit the target and reflects back. The same antenna and the time difference

between the signal transmission and reception is calculated, which will help up to

measure the distance of the target from the radar.

5.1Fundamentals

Fig 5.1: Block diagram of an elementary pulse radar set

Basic radar system: The block diagram of an elementary pulsed radar set is

shown in Fig. For each transmitted pulse, the cycle of events is as follows. Figure 1

Block diagram of an elementary pulse radar se

In response to an internally generated trigger signal, the transmitter generates a

short, rectangular pulse. As soon as a small fraction of the pulse power is fed to the

duplexer, this device disconnects the receiver from the antenna and connects the

transmitter to it. In most radars, though by no means in all, the antenna moves in a

predetermined pattern, i.e., it scans. Either way, it is normally directional and sends

out the generated pulse in the direction in which it is pointing at the time. The

scanning speed may be mechanically high, but it is small compared with the time

Dept of ECE, VIT

Transmitter

Receiver

Duplexer


taken by pulses to return from a normal range of targets. Thus, when such echoes are

received, the antenna still points in the right direction to collect them.

As soon as the transmitted pulse terminates, the duplexer disconnects the

transmitter from the antenna. The duplexer also reconnects the receiver to the antenna,

allowing the returning echoes to be correctly processed. The received pulses are

amplified and demodulated by the receiver. The pulses from the returning echoes (and

noise, of course) are then fed to the device on which they are to be displayed, as will

be described. The cycle is complete, and the set is once again ready for the

transmission of the next pulse and the succeeding ones, while the antenna scans along

its predetermined path

The radar set is able to show the position of the target, because information

about the azimuth (horizontal direction) and the elevation (vertical direction) of the

antenna is available. In addition, the distance to the target may transmitter output

tubes, and the first stage of the receiver is often a diode mixer. The antenna generally

uses a parabolic reflector of some form, as will be mentioned in Sec.

Development of radar from its inception, radar has used a system of sending

short, powerful pulses of radio energy and then analyzing the returned echoes to

determine the position, distance and possibly velocity of the target. However, the

methods of doing so have evolved and become far more refined and sophisticated as

time has gone by. The primary incentive as in so many other things was the imminence

of war. Radar was made possible by a technology, which, at the time war broke out, was

just beginning to show promise. This technology itself took great strides forward to

meet the new challenges imposed by war.

The first radars worked at much lower frequencies than present systems (as loq

as 60MHz for the original British coastal air-warning radar because of a lack of

sufficiently powerful transmitting tubes at higher frequencies. This was changed in 1940

with the appearance of the cavity magnetron, and the stage was then set for the

development of modern radar. As can be appreciated, one of the prime requirements of a

radar system is that it should have a fair degree of accuracy in its indication of target

direction. This is possible only if the antennas used are narrow beam ones, i.e., have

dimensions of several wavelengths. That requirement cannot be fulfilled satisfactorily

unless the wavelengths themselves are fairly short, corresponding to the upper UHF or

microwave frequencies.

Dept of ECE, VIT


5.2 CALCULATIONS

Fig 5.2: calculations of Parameters

T =time b/w signal transmission and reception.

2R = Total distance traveled.

c = Velocity of electromagnetic signals = 3*108 m/sec.

Velocity = distance / time

i.e.; C = 2R / T

Or

R =CT /2

So in the screen an obstacle will be shown at a distance R from the radar.

Dept of ECE, VIT

OBJECT

RADAR

R

radar bullet seminar report - baixardoc

Documents

Transcript of radar bullet seminar report - baixardoc