(A modern approach in wireless communication)

ADAPTIVE MISSILE GUIDANCE USING GPS

Prepared by:

Pakal Shivani M.

ContentsIntroductionHistoryWhat is missile guidanceTypes of missile guidanceIntroduction to GPSWhat are the elements og GPSIntroduction to DGPSMissile Guidance using GPSActual Working of GPS Guidance SystemHow does GPS finds the exact target locationInertial Navigation SystemFlow ChartGuidance EquipmentsConclusion

‘ADAPTIVE MISSILE GUIDANCE USING GPS’ is a modern approach in wireless communication.

For the day to day world of wars and battles, the new techniques to throw an attack on the opposing team are emerging immensely. This had led to the development of various types of guided missiles.

Introduction

American rocket pioneer Robert Goddard. experimented with rudimentary gyroscopic systems. The systems entered more widespread use with the advent of spacecraft, guided missiles, and commercial airliners.

HISTORY

Missile guidance refers to a variety of methods of guiding a missile or a guided bomb to its intended target. The missile's target accuracy

is a critical factor for its effectiveness.

What is Missile Guidance???

On the battlefield of today, guided missiles are guided to or acquire their targets by using:

Radar signal,Wires,Lasers (or),Most recently GPS.

TYPES OF MISSILE GUIDANCE

The Global Positioning System (GPS) is a space-based satellite navigation system that provides location and time information in all weather, anywhere on or near the Earth, where there is an unobstructed line of sight

to four or more GPS satellites.

INTRODUCTION TO GPS

GPS has three parts: the space segment, the user segment, and the control segment. The space segment consists of a constellation of 24 satellites plus some spares, each in its own orbit 11,000 nautical miles above Earth.

What are the Elements of GPS ?

Differential Global Positioning System (DGPS) is an enhancement to Global Positioning System (GPS), that provides improved location accuracy, from the 15-meter nominal GPS accuracy to about 10 cm in case of the best implementations.

INTRODUCTION TO DGPS…

The central idea behind the design of DGPS/GPS/inertial guided weapons is that of using a 3-axis gyro/accelerometer package as an inertial reference for the weapon's autopilot.

MISSILE GUIDANCE USING GPS

Such weapons are designated as "accurate" munitions as they will offer CEPs (Circular Error Probable) of the order of the accuracy of

GPS P -code signals, typically about 40ft.

(Continued)

An inertial navigation system (INS) is a navigation aid that uses a computer, motion sensors and rotation sensors (gyroscopes) to continuously calculate via dead reckoning the position, orientation, and velocity (direction and speed of movement) of a moving object without the need for external references.

ACTUAL WORKING OF GPS GUIDANCE SYSTEM…

The ‘Missile guidance using GPS’ uses this ‘Inertial Navigation System’ as its basic concept.

Continued…

In the figure at left, the dashed lines show the actual intersection point, and the gray bands indicate the area of uncertainty.

In this diagram, the solid lines indicatewhere the GPS receiver "thinks" the target is located. Because of errors in thereceiver's internal clock, these spheres donot intersect at one point.

HOW DOES GPS FINDS THE EXACT POSITION OF THE TARGET??

Continued……

•The GPS receiver must change the size of the spheres until the intersection point is determined. The relative size of each sphere has already been calculated, so if the size of one sphere is changed, the other spheres must be adjusted by exactly the same amount.

Inertial navigation relies on devices onboard the missile that senses its motion and acceleration in different directions. These devices are called gyroscopes and accelerometers.

HOW DOES THE ‘INERTIAL NAVIGATION SYSTEM WORKS???

INTERNAL SRTUCTURE OF THE GUIDED MISSILE

FLOWCHART…..

TARGET SHOOT BY USING RADAR SIGNAL

TARGET SHOOT BY USING GPS.

The way these the subsystems are distributed between the missile and the launcher result in two different categories:Remote Control Guidance: The guidance computer is on the launcher. The target tracker is also placed on the launching platform.Homing Guidance: The guidance computers are in the missile and in the target tracker.

GUIDING EQUIPMENTS

WHY GPS GUIDANCE???

•The GPS receiver catches the change in the size of the spheres until the intersection point is determined.

CONCLUSIONThus, after overall view of all the missile guidance systems we come to an conclusion that “Adaptive Missile Guidance Using GPS” is the most efficient method to chase any target as it saves economical losses, environmental losses & various other losses which were faced during early wars.