radar project

7/26/2019 RADAR Project

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ABSTRACT

All targets produce a diffuse reflection i.e. it is reflected in a wide number of directions. The

reflected signal is also called scattering. Backscatter is the term given to reflections in theopposite direction to the incident rays. Radar signals can be displayed on the traditional plan

position indicator (PPI) or other more advanced radar display systems. A PPI has a rotating

vector with the radar at the origin, which indicates the pointing direction of the antenna and

hence the bearing of targets. It shows a map-like picture of the area covered by the radar beam.


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OBJECTIVE

The object of this project is to design a simple, easy to install, microcontroller based wireless

radar system using Zigbee to detect an object nearby. The radar moves 360degree using step

motor therefore covering every possible direction. The radar system detects any obstacle in itspath and transmits its angle through Zigbee to the receiver display. The range can be increased

by replacing low cost IR radar SENSOR by any high cost SENSOR.


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INDEX

CHAPTER NO. TITLE PAGE NO.

Chapter 1 Introduction

1.1Introduction

1.2 Signal Routing

Chapter 2 Historical Overview

Chapter 3 Basics Of Radar

3.1 Introduction

3.2 Antennas

3.3 Duplexer

Chapter 4 Direction Determination

4.1 Bearing

4.2 Radar Resolution

4.3 Angular Resolution

Chapter 5 Parts Of The System

5.1 IR Sensor

5.2 Microcontroller

5.3 Wireless Camera

5.4 Step Motor

5.5 Zig Bee

5.6 LCD

Chapter 6 Transmitter And Receiver Section

6.1 Block Diagram Of Transmitter

6.2 Block Diagram Of Receiver

6.3 Pin Diagram Of Transmitter

6.4 Pin Diagram Of Receiver


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6.5 Buzzer Circuit

6.6 Power Supply Circuit

Chapter 7 Component List

Chapter 8 Microcontroller 89s52

8.1 Introduction

8.2 Features

8.3 Block Diagram

8.4 Pin Diagram

8.5 Memory Organisation

Chapter 9 Zig-Bee (Xbee And Xbee-Pro Rf Modules)

9.1 Introduction

9.2 Features

9.3 Pin Diagram

9.4 Pin Descriptions

Chapter 10 Other Components Used

10.1 Stepper Motor

10.1.1 Basics Of Operation

10.1.2 Characteristics

10.1.3 Types Of Stepper Motors

10.1.4 Step Modes

10.1.5 How Stepper Motors Work

10.2 Voltage Regulator (7805)


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10.2.1 Features

10.3 The Ir Light Emitter

10.3.1 Principle Of Operation

10.3.2 Description

10.3.3 Features

10.4 Ir Light Detector

10.4.1 Description

10.4.2 Qse 973 Features

10.5 Liquid Crystal Display

10.5.1 Block Diagram

10.5.2 Overview

10.6 Uln2003

10.6.1 Description

10.7 Operational Amplifier

10.7.1 Pin Diagrram

10.7.2 Description

Chapter 11 Project Code

11.1 Transmitter Microcontroller Code

11.2 Receiver Microcontroller Code

Chapter 12 Conclusion

Bibliography


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LIST OF FIGURES

FIG. TITLE PAGE NO.

Fig.1.1 Radar Principle

Fig.1. 2 Block Diagram Of A Primary Radar With The Signal Flow

Fig.2.1 Wrzburg Riese, World War II radar produced in 1940 byTelefunken (Germany)

Fig.3.3 A schematic diagram of radar

Fig.4.1 Angular Resolution Using Coordinate Axis

Fig.4.3 Angular Resolution

Fig.5.1 IR Sensor

Fig.5.4 Step Motor

Fig.6.1 Block Diagram of Transmitter Section

Fig.6.2 Block Diagram of Receiver

Fig.6.3 Pin Diagram Of Transmitter

Fig.6.4 Pin Diagram of Receiver

Fig.6.5 Circuit Diagram Of Buzzer

Fig.6.6 Power Supply Circuit

Fig.8.3 Block Diagram Of Microcontroller 89s52

Fig.8.4 Pin Diagram Of 89s52

Fig.9.3 Pin Diagram of ZIG Bee

Fig.10.1.5.1 Working of Stepper motor I

Fig. 10.1.5.2 Working of Stepper Motor II

Fig.10.1.5.3 Four Phase Stepper motor


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Fig.10.2.1 Pin Diagram Of Voltage Regulator 7805

Fig.10.7.2 Internal Connections of Operational amplifier

Fig.10.3.2 IR LED Schematic Diagram

Fig.10.4.1 IR Photo diode

Fig.10.5.1 Block Diagram of LCD

Fig.10.6 Apperance of an ULN2003 IC

Fig.10.6.1 Pin Description of ULN2003

Fig.10.7.1 Pin Diagram of Operational Amplifier

Fig.10.3.1 Wavelength vs. Radiant Power


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CHAPTER 1

INTRODUCTION

1.1INTRODUCTION

The term radar is generally understood to mean a method by means of which short

electromagnetic waves are used to detect distant objects and determine their location and

movement. The term RADAR is an acronym from

RAdioDetectionAndRanging

A complete radar measuring system is comprised of a transmitter with antenna, a transmission

path, the reflecting target, a further transmission path (usually identical with the

first one), and a receiver with antenna. Two separate antennas may be used, but often

just one is used for both transmitting and receiving the radar signal.The electronic principle on which radar operates is very similar to the principle of sound-wave

reflection. If you shout in the direction of a sound-reflecting object (like a rocky canyon or cave),

you will hear an echo. If you know the speed of sound in air, you can then estimate the distance

and general direction of the object. The time required for an echo to return can be roughly

converted to distance if the speed of sound is known.

Radar uses electromagnetic energy pulses in much the same way, as shown in Figure 1. The

radio-frequency (RF) energy is transmitted to and reflected from the reflecting object. A small

portion of the reflected energy returns to the radar set. This returned energy is called an ECHO,

just as it is in sound terminology. Radar sets use the echo to determine the direction and distance

of the reflecting object.

Fig. 1.1 Radar Principle


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As implied by this contraction, radars are used to detect the presence of an aim (as object of

detection) and to determine its location. The contraction implies that the quantity measured is

range. While this is correct, modern radars are also used to measure range and angle. The

following figure shows the operating principle of primary radar. The radar antenna illuminates

the target with a microwave signal, which is then reflected and picked up by a receiving device.

The electrical signal picked up by the receiving antenna is called echo or return. The radar signal

is generated by a powerful transmitter and received by a highly sensitive receiver.

Fig.1. 2 Block Diagram Of A Primary Radar With The Signal Flow

1.2 Signal Routing

The radar transmitter produces short duration high-power RF- pulses of energy.

The duplexer alternately switches the antenna between the transmitter and receiver so

that only one antenna need be used. This switching is necessary because the high-power

pulses of the transmitter would destroy the receiver if energy were allowed to enter the

receiver.

The antenna transfers the transmitter energy to signals in space with the required

distribution and efficiency. This process is applied in an identical way on reception.


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The transmitted pulses are radiated into space by the antenna as an electromagnetic

wave. This wave travels in a straight line with a constant velocity and will be reflected by

an aim.

The antenna receives the back scattered echo signals.

During reception the duplexer lead the weakly echo signals to the receiver.

The hypersensitive receiver amplifies and demodulates the received RF-signals. The

receiver provides video signals on the output.

The indicator should present to the observer a continuous, easily understandable, graphic

picture of the relative position of radar targets.


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CHAPTER 2

HISTORICAL OVERVIEW

Neither a single nation nor a single person is able to say, that he (or it) is the inventor of the radar

method. One must look at the Radar than an accumulation of many developments andimprovements earlier, which scientists of several nations parallel made share. There arenevertheless some milestones with the discovery of important basic knowledge and importantinventions:

Fig. 2.1 Wrzburg Riese, World War II radar produced in 1940 by Telefunken

(Germany)

1865 The English physicist James Clerk Maxwell developed his electro-magnetic light theory(Description of the electro-magnetic waves and her propagation)

1886 The German physicist Heinrich Rudolf Hertz discovers the electro-magnetic waves andproves the theory of Maxwell with that.

1904 The German high frequency engineer Christian Hlsmeyer invents theTelemobiloskop to the traffic supervision on the water. He measures the running timeof electro-magnetic waves to a metal object (ship) and back. A calculation of the distanceis thus possible. This is the first practical radar test. Hlsmeyer registers his invention tothe patent in Germany and in the United Kingdom.

1917 The French engineer Lucien Lvy invents the super-heterodyne receiver. He uses as first

the denomination Intermediate Frequency, and alludes the possibility of doubleheterodyning.

1921 The invention of the Magnetron as an efficient transmitting tube by the US-Americanphysicist Albert Wallace Hull

1922 The American electrical engineers Albert H. Taylor and Leo C. Young of the NavalResearch Laboratory (USA) locate a wooden ship for the first time.

1930 Lawrence A. Hyland (also of the Naval Research Laboratory), locates an aircraft for thefirst time.


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1931 A ship is equipped with radar. As antennae are used parabolic dishes with horn radiators.

1936 The development of the Klystron by the technicians George F. Metcalf and William C.Hahn, both from General Electric. This will be an important component in radar units asan amplifier or an oscillator tube.

1940 Different radar equipments are developed in the USA, Russia, Germany, France and

Japan.The reasoning to use of electric magnetic waves to the locating of ships has beenregistered of the engineer of Dsseldorf, Christian Hlsmeyer, already 1904 in Germanyand England as a patent. One finds the illustration in the patent specification of a steamerwhich detects an approaching ship with help of the backscattering. Tests carried out onthe Rhine River had in principle yielded the usefulness of this method.


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CHAPTER 3

BASICS OF RADAR

3.1 INTRODUCTION

Radars are very complex electronic and electromagnetic systems. Often they are

complex mechanical systems as well. Radar systems are composed of many different

subsystems, which themselves are composed of many different components. There is a great

diversity in the design of radar systems based on purpose, but the fundamental operation and

main set of subsystems is the same. In this paper, I will discuss some of the subsystems and

important components that are found in typical portable monostatic pulsed ground surveillance

radar systems. I follow a bottom-up approach in developing this paper, first discussing

components, then subsystems, and finally whole systems.

3.2 ANTENNAS

The radar antenna acts as the interface between the radar system and free space through

which radio waves are transmitted and received. The purpose of the radar antenna is to

transduce free space propagation to guided wave propagation during reception and the opposite

during transmission. During transmission, the radiated energy is concentrated into a shaped

beam which points in the desired direction in space. During reception, the antenna collects the

energy contained in the echo signal and delivers it to the receiver. In the radar range equation,these two roles were expressed by the transmitter gain, G, and effective receiving aperture, Ae,

given by

These two values are proportional, so optimizing for both transmitting and receiving is possible.The proportionality is given by


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3.3 DUPLEXER

When a single antenna is used for both transmission and reception, as in most monostatic

radar systems, a duplexer must be used. A duplexer switches the radar system from transmit

mode to receive mode. There are four main requirements that must be met by an effective radar

duplexing system. During transmission, the switch must connect the antenna to the transmitter

and disconnect it from the receiver. The receiver must be thoroughly isolated from the

transmitter during the transmission of the high-power pulse to avoid damage to sensitive receiver

components. After transmission, the switch must rapidly disconnect the transmitter and connect

the receiver to the antenna. For targets close to the radar to be detected, the action of the switch

must be extremely rapid. The switch should have very little insertion loss during both

transmission and reception.

The simplest solution to the duplexer problem is to use a switch to transfer the antenna

connection from the receiver to the transmitter during the transmitted pulse and back to the

receiver during the return pulse. Since no practical mechanical switches are available that can

open and close in a few microseconds, electronic switches are used. For radars with waveguide

antenna feeds, waveguide junction circulators are often used as duplexers. A circulator is a

nonreciprocal ferrite device, which contains three or more ports. A three-port ferrite junction

circulator, called the Y-junction circulator, is most commonly used. The Y-junction circulator

uses spinel ferrites or garnet ferrites in the presence of a magnetic bias field, to provide anonreciprocal

effect. A schematic diagram is shown in Figure .

Fig.3.3 A schematic diagram of radar


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If a signal is applied at the transmitter port, it will emerge from the antenna port with a

loss characteristic called insertion loss. Typical values of insertion loss are 0.1 to 0.5 dB. In the

reverse direction, there will be leakage at the receiver port from the incoming signal at the

transmitter port. This leakage, called isolation, is typically 20 dB below incoming power at the

transmitter port. Due to the symmetry of the Y-junction, the behavior is the same for the other

ports, with respect to other port pairs.

Radio Frequency Subsystem

The Radio Frequency (RF) system takes a signal from the transmitter and eventually

propagates it in free space during transmission. The RF system takes a signal from free space

and passes it to the receiver during reception. The RF system generally consists of an antenna

feed and antenna, a duplexer, and some filters. Often devices are needed to convert waveguide

propagation into coaxial cable propagation. Filtering is used to attenuate out-of-band signals

such as images and interference from other radars or high-powered electrical devices during

reception. During transmission, filtering is used to attenuate harmonics and images. The

preselector filter is a device that accomplishes these two filtering objectives. The duplexer

provides isolation between the transmitter and receiver to protect the sensitive receiver during

the high energy transmit pulse. The antenna feed collects energy as it is received from the

antenna or transmits energy as it is transmitted from the antenna. The antenna is the final stage

in the RF system during transmission or the first stage during reception. It is the interface with

the medium of radio wave propagation.


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CHAPTER 4

DIRECTION DETERMINATION

4.1 BEARING

The direction to the target is determined by the directivity of the antenna. Directivity, sometimes knownas the directive gain, is the ability of the antenna to concentrate the transmitted energy in a particulardirection. An antenna with high directivity is also called a directive antenna. By measuring the directionin which the antenna is pointing when the echo is received, both the azimuth and elevation angles fromthe radar to the object or target can be determined. The accuracy of angular measurement is determinedby the directivity, which is a function of the size of the antenna.

Fig.4.1 Angular Resolution Using Coordinate Axis

The True Bearing (referenced to true north) of a radar target is the angle between true north and a linepointed directly at the target. This angle is measured in the horizontal plane and in a clockwise direction

from true north. The bearing angle to the radar target may also be measured in a clockwise direction fromthe centerline of your own ship or aircraft and is referred to as the relative bearing. The rapid andaccurate transmission of the bearing information between the turntable with the mounted antenna and thescopes can be carried out for

servo systems and

counting of azimuth change pulses.

Servo systems are used in older radar antennas and missile launchers and works with help of devices likesynchro torque transmitters and synchro torque receivers. In other radar units we find a system ofAzimuth-Change-Pulses (ACP). In every rotation of the antenna a coder sends many pulses, these arethen counted in the scopes. Some radar sets work completely without or with a partial mechanical motion.These radars employ electronic phase scanning in bearing and/or in elevation


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4.2 RADAR RESOLUTION

The target resolution of radar is its ability to distinguish between targets that are very close in either rangeor bearing. Weapons-control radar, which requires great precision, should be able to distinguish betweentargets that are only yards apart. Search radar is usually less precise and only distinguishes betweentargets that are hundreds of yards or even miles apart. Radar resolution is usually divided into twocategories; range resolution and angular (bearing) resolution.

4.3 ANGULAR RESOLUTION

Angular resolution is the minimum angular separation at which two equal targets at the same range can beseparated. The angular resolution characteristics of a radar are determined by the antenna beam widthrepresented by the -3 dB angle which is definedby the half-power (-3 dB) points. The half-powerpoints of the antenna radiation pattern (i.e. the -3 dB beam width) are normally specified as the limits ofthe antenna beam width for the purpose of defining angular resolution; two identical targets at the samedistance are, therefore, resolved in angle if they are separated by more than the antenna beam width. An

important remark has to be made immediately: the smaller the beam width , the higher the directivity ofthe radar antenna, the better the bearing resolution. The angular resolution as a distance between twotargets depends on the slant-range and can be calculated with help of the following formula:

Fig.4.3 Angular Resolution


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CHAPTER 5

PARTS OF THE SYSTEM

a. IR SENSOR

b. Microcontrollers

c. Wireless camera

d. Step Motor

e. Zig bee.

f. LCD

5.1 IR SENSOR

IR transmitter is used to transmit IR signal in a particular direction and after reflecting from the

obstacle receive the signal back.

Fig.5.1 IR Sensor


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5.2 MICROCONTROLLER

The microcontroller is the heart of the embedded system. It constantly monitors the digitized

outputs of IR Sensor and zigbee. It constantly checks the received signal sensor with the given

threshold and thus sends the particular angel through Zigbee to the receiver.

5.3 WIRELESS CAMERA

Wireless camera is used to give the picture of the obstacle detected by the IR Sensor. Camera is

placed with the IR Sensor

5.4 STEP MOTOR

Step motor is used to rotate the IR Sensor 360 degree, so that it can scan every direction and

angle is obtained by using its rotation.

Fig.5.4 Step Motor

5.5 ZIG BEE

Zig bee is used here to transmitt data wirelessly to the receiver. Here we are using pair of Zigbees which are synchronized so that data can be sent from transmitter to receiver.zigbee acts as

Antenna.

5.6 LCD

LCD is used to display the angle of the detected obstacle.


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CHAPTER 6

TRANSMITTER AND RECEIVER SECTION

6.1 BLOCK DIAGRAM OF TRANSMITTER

Fig. 6.1 Block Diagram of Transmitter Section

WORKING (TX)

The Microcontroller is the centre of the system, it gives command signals for operation the

operation of the stepper motor IR sensor and camera. The stepper motor is connected to the

microcontroller via buffer IC which gives the motor suitable current and voltage foroperation,it

Zigbee module

Microcontroller

Power circuit for

zigbee and controller

Buffer ic for

stepper motor

Stepper motorInterfacing IC

for IR Sensor

SENSOR

RELAY

CAMERA


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act as an interface for the motor. The IR sensor is connected to the microcontroller through the

operational amplifier which acts as the comperator. The camera is connect through the relay

circuit to the microcontroller. Different power supplies are given to the various components.

5V supply for microcontroller 3.3V for zigbee and 12V for motor. Zigbee is connected to the

microcontroller for serial transmission of data from transmitter to receiver.

6.2 BLOCK DIAGRAM OF RECEIVER

Fig.6.2 Block Diagram of Receiver

Zigbee module

Microcontroller Power circuit for

zigbee and controller

LCD 16*2

BUZZER

SWITCHES


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WORKING (RX)

The block diagram of the receiver is given above. The transmitted data is received by the zig bee

and given to the microcontroller. The two zigbee are paired together so that data can be shared

between them. The data received is processed and given to the LCD for display. LCD display the

degree of the object seen. And at the same time buzzer starts. Different switches are used for

camera operation and starter switch which starts the motor again to rotate. Here power supply

circuit is also used at the receiver.

6.3 PIN DIAGRAM OF TRANSMITTER

Fig.6.3 Pin Diagram Of Transmitter

The microcontroller 8052 is used here because of its internal 8 Kbyte ROM. Various components

of the system are connected directly or through interfaces. External oscillator circuit is connecte

to Pin 18 and 19 for clock pulse generation. Microcontroller controls every operations of the

system. Port 0 is used to interface the stepper motor with the microcontroller via ULN 2003.


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ULN 2OO3 is a driver chip which driver various high current components, here it is used to

drive the stepper motor. It provide suitable voltage and current for the operation of stepper

motor. 4 input pins of the chip are connected to the Port 0 which is externally using 10kpull up

resistors, the Vcc of the chip is given 12V voltage. Pin 31 of c is at logic high because we are

using internal ROM only. IR sensor is connected to the LM324N operational amplifier which

act as a comparator circuits compares the input signal from the sensor with the threshold, and

accordingly gives output signal to the microcontroller on the Pin 21. Camera is connected

through the relay with the microcontroller on Pin 22. The zig bee chip which act as an antenna in

the system is connected to the Port 3 pin 10 & 11. Who have dual functions as serial for

microcontroller. Zigbee is connected to the 3.3V supply voltage. The signal is transmitted from

one zig bee to the paired one on the receiver side.

6.4 PIN DIAGRAM OF RECEIVER

The receiver of the system uses the microcontroller of the 8052 microcontroller family. Crystal

oscillator is connected to the microcontroller externally on the clock pins of the microcontroller

to drive the clock of microcontroller which needs external oscillator to generate clock pulses.

Fig.6.4 Pin Diagram of Receiver

The Pin 31 is connected to the Vcc for the same reason as above. Port 1 is used to interface the

LCD, this port acts as data lines for the LCD, Pins 7 to 14 of LCD are connected to the Port 1 of


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the microcontroller. Pin 9 of the microcontroller is connected to the Vcc via a 10F capacitor

this acts as the reset circuit for the microcontroller. Pins 10 & 11 are connected to the zig bee for

reception and transmission of data from the other end. Different switches are connected to the

pins 22 to 26 for various purposes. Pins 4 ,5, & 6 of LCD are connected to the 21, 22, & 23 Pins

of microcontroller for RD/WR ,RESET & DATA/CODE respectively. Pin 3 of LCD is

connected to the variable resistor which controls the contract of LCD.

6.5 BUZZER CIRCUIT

Fig.6.5 Circuit Diagram Of Buzzer

OPERATION

The buzzer is used in the system so when the sensor detects the object it produces the suitable

high pitch signal or horn indicating that the sensor has detected the object in its path. It is

connected to the PIN 16 of the microcontroller and when the object is detected the Pin 16 goes

high thus activating the buzzer circuit. When the Pin 16 goes high current flows from Vccthrough 10 kresistor to the transistor and goes to the GND, thus transistor is activated and the

path is made for buzzer current to flow, so the current flows from Vcc through buzzer and

transistor to the ground. When the Pin 16 is low whole current flows from Vcc to the Pin 16 and

thus transistor remains cutoff.


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6.6 POWER SUPPLY CIRCUIT

Fig.6.6 Power Supply Circuit

A typical power supply consists of various stages. The A.C voltage(220v, 50Hz) is given to the

primary coil of (12-0-12) transformer. The transformer steps down the A.C voltage to 12V. The

step down voltage is rectified by 2 IN4007 diodes. Thus the rectifier converts A.C into pulsating

D.C voltage. A pulsating D.C voltage means a unidirectional voltage containing large varying

component called ripple in it. The filter circuit is used after a rectifier circuit to reduce the ripple

Content in the pulsating D.C. and tries to make it smoother. Here a capacitor of 10F is used as

filter. LM 7809, LM 7805, LM 2950 are used to to obtain regulated supply of + 9V , +5V,

+3.3V respectively in the circuit.


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CHAPTER 7

COMPONENT LIST

S.NO COMPONENT NAME QTY

01. Microcontroler AT89s52 02

02. Crystal 11.0592 Mhz 02

03. Battery 9V 01

04. Xbee modules 02

05. Capacitor 10microfarad, 25V 02

06. Capacitor 33Picofarad 04

07. LCD 01

08. Ic7805 02

09. 40 pin IC base 02

10. Relimix connectors(4 pin) 02

11. Microswitches 06

12. LEDs 05

13. Transistor BC547 02

14. Diode 4007 02

15. Resistances 2.2k 10

16. Resistances 1k 05

17. Resistances 10k 02

18. Uln2003 01

19. Stepper Motor 0120. Bridge connector 01

21. Buzzer 01

23. Proximity diffuse IR sensor 01

24. L293d 01


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CHAPTER 8

MICROCONTROLLER 89S52

8.1 INTRODUCTION

The AT89S52 is a low-power, high-performance CMOS 8-bit microcontroller with 8K bytes of

in-systemprogrammable Flash memory. The device is manufactured using Atmels high-density

nonvolatile memory technology and is compatible with the indus-try-standard 80C51 instruction

set and pinout. The on-chip Flash allows the program memory to be reprogrammed in-system or

by a conventional nonvolatile memory pro-grammer. By combining a versatile 8-bit CPU with

in-system programmable Flash on a monolithic chip, the Atmel AT89S52 is a powerful

microcontroller which provides a highly-flexible and cost-effective solution to many embedded

control applications. The AT89S52 provides the following standard features: 8K bytes of Flash,

256 bytes of RAM, 32 I/O lines, Watchdog timer, two data pointers, three 16-bit timer/counters,

a six-vector two-level interrupt architecture, a full duplex serial port, on-chip oscillator, and

clock circuitry. In addition, the AT89S52 is designed with static logic for operation down to zero

frequency and supports two software selectable power saving modes. The Idle Mode stops the

CPU while allowing the RAM, timer/counters, serial port, and interrupt system to continue

functioning. The Power-down mode saves the RAM con-tents but freezes the oscillator,

disabling all other chip functions until the next interrupt or hardware reset.

8.2 FEATURES

Compatible with MCS-51 Products

8K Bytes of In-System Programmable (ISP) Flash MemoryEndurance: 1000 Write/Erase

Cycles

4.0V to 5.5V Operating Range

Fully Static Operation: 0 Hz to 33 MHz

Three-level Program Memory Lock


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256 x 8-bit Internal RAM

32 Programmable I/O Lines

Three 16-bit Timer/Counters

Eight Interrupt Sources

Full Duplex UART Serial Channel

Low-power Idle and Power-down Modes

Interrupt Recovery from Power-down Mode

Watchdog Timer

Dual Data Pointe

r Power-off Flag

Fast Programming Time

Flexible ISP Programming (Byte and Page Mode)

Green (Pb/Halide-free) Packaging Option


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8.3 BLOCK DIAGRAM

Fig.8.3 Block Diagram Of Microcontroller 89s52


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8.4 PIN DIAGRAM

40-lead PDIP:

Fig.8.4 Pin Diagram Of 89s52


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PIN DESCRIPTION

VCC: Supply voltage

GND: Ground

PORT 0

Port 0 is an 8-bit open drain bidirectional I/O port. As an output port, each pin can sink eight

TTL inputs. When 1s are written to port 0 pins, the pins can be used as high-impedance inputs.

Port 0 can also be configured to be the multiplexed low-order address/data bus during accesses to

external program and data memory. In this mode, P0 has internal pull-ups. Port 0 also receives

the code bytes during Flash programming and outputs the code bytes dur-ing program

verification. External pull-ups are required during program verification

PORT 1

Port 1 is an 8-bit bidirectional I/O port with internal pull-ups. The Port 1 output buffers can

sink/source four TTL inputs. When 1s are written to Port 1 pins, they are pulled high by the

inter-nal pull-ups and can be used as inputs. As inputs, Port 1 pins that are externally being

pulled low will source current (IIL) because of the internal pull-ups. In addition, P1.0 and P1.1

can be configured to be the timer/counter 2 external count input (P1.0/T2) and the timer/counter2 trigger input (P1.1/T2EX), respectively, as shown in the follow-ing table. Port 1 also receives

the low-order address bytes during Flash programming and verification.


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PORT 2




pulled low will source current (IIL) because of the internal pull-ups. Port 2 emits the high-order

address byte during fetches from external program memory and dur-ing accesses to external data

memory that use 16-bit addresses (MOVX @ DPTR). In this application, Port 2 uses strong

internal pull-ups when emitting 1s. During accesses to external data memory that use 8-bit

addresses (MOVX @ RI)

PORT 3




pulled low will source current (IIL) because of the pull-ups. Port 3 receives some control signals

for Flash programming and verification. Port 3 also serves the functions of various special

features of the AT89S52, as shown in the following table:


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RST (Reset input):

A high on this pin for two machine cycles while the oscillator is running resets the device. This

pin drives high for 98 oscillator periods after the Watchdog times out. The DISRTO bit in SFR

AUXR (address 8EH) can be used to disable this feature. In the default state of bit DISRTO, the

RESET HIGH out feature is enabled.

ALE/PROG:

Address Latch Enable (ALE) is an output pulse for latching the low byte of the address during

accesses to external memory. This pin is also the program pulse input (PROG) during Flash

programming. In normal operation, ALE is emitted at a constant rate of 1/6 the oscillator

frequency and may be used for external timing or clocking purposes. If desired, ALE operation

can be disabled by setting bit 0 of SFR location 8EH. With the bit set, ALE is active only during

a MOVX or MOVC instruction. Otherwise, the pin is weakly pulled high. Setting the ALE-

disable bit has no effect if the microcontroller is in external execution mode.

PSEN PROGRAM STORE ENABLE (PSEN)

is the read strobe to external program memory. When the AT89S52 is executing code from

external program memory, PSEN is activated twice each machine cycle, except that two PSEN

activations are skipped during each access to exter-nal data memory

EA/VPP( External Access Enable):

EA must be strapped to GND in order to enable the device to fetch code from external program

memory locations starting at 0000H up to FFFFH. Note, however, that if lock bit 1 is

programmed, EA will be internally latched on reset. EA should be strapped to VCC for internal

program executions. This pin also receives the 12-volt programming enable voltage (VPP)

during Flash programming.

XTAL1: Input to the inverting oscillator amplifier and input to the internal clock operating

circuit.

XTAL2:Output from the inverting oscillator amplifier.


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8.5 MEMORY ORGANISATION

MCS-51 devices have a separate address space for Program and Data Memory. Up to 64K bytes

each of external Program and Data Memory can be addressed.

PROGRAM MEMORY

If the EA pin is connected to GND, all program fetches are directed to external memory. On the

AT89S52, if EA is connected to VCC, program fetches to addresses 0000H through 1FFFH are

directed to internal memory and fetches to addresses 2000H through FFFFH are to external

memory

DATA MEMORY

The AT89S52 implements 256 bytes of on-chip RAM. The upper 128 bytes occupy a parallel

address space to the Special Function Registers. This means that the upper 128 bytes have the

same addresses as the SFR space but are physically separate from SFR space. When an

instruction accesses an internal location above address 7FH, the address mode used in the

instruction specifies whether the CPU accesses the upper 128 bytes of RAM or the SFR space.

Instructions which use direct addressing access the SFR space. For example, the following direct

addressing instruction accesses the SFR at location 0A0H (which is P2). MOV 0A0H, #data

Instructions that use indirect addressing access the upper 128 bytes of RAM. For example, the

following indirect addressing instruction, where R0 contains 0A0H, accesses the data byte at

address 0A0H, rather than P2 (whose address is 0A0H). MOV @R0, #data Note that stack

operations are examples of indirect addressing, so the upper 128 bytes of data RAM are available

as stack space.


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CHAPTER 9

ZIG-BEE (XBee and XBee-PRO RF Modules)

9.1 INTRODUCTION

The XBee and XBee-PRO RF Modules were engineered to meet IEEE 802.15.4 standards and

support the unique needs of low-cost, low-power wireless sensor networks. The modules require

minimal power and provide reliable delivery of data between devices. The modules operate

within the ISM 2.4 GHz frequency band and are pin-for-pin compatible with each other.

9.2 FEATURES

1. Long Range Data Integrity

XBee

Indoor/Urban: up to 100 (30 m)

Outdoor line-of-sight: up to 300 (90 m)

Transmit Power: 1 mW (0 dBm)

Receiver Sensitivity: -92 dBm

Advanced Networking & Security

Retries and AcknowledgementsDSSS (Direct Sequence Spread Spectrum)

Each direct sequence channels has over 65,000 unique network addresses available

Source/Destination Addressing

Unicast & Broadcast Communications

Point-to-point, point-to-multipoint and peer-to-peer topologies supported

Low PowerXBee

TX Peak Current: 45 mA (@3.3 V

RX Current: 50 mA (@3.3 V)

Power-down Current: < 10


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ADC and I/O line support

Analog-to-digital conversion, Digital I/OI/O Line Passing

Easy to Use

No configuration necessary for out-of box RF communications

Free X-CTU Software (Testing and configuration software)

AT and API Command Modes for configuring module parameters

Extensive command set

Small form factor

9.3 PIN DIAGRAM

Fig.9.3 Pin Diagram of ZIG Bee


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9.4 PIN DESCRIPTIONS


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CHAPTER 10

OTHER COMPONENTS USED

10.1 STEPPER MOTOR

A stepper motor(or step motor) is abrushless,synchronouselectric motor that can divide a

full rotation into a large number of steps. The motor's position can be

controlledprecisely without any feedback mechanism (seeOpen-loop controller), as long as the

motor is carefully sized to the application. Stepper motors are similar toswitched reluctance

motors (which are very large stepping motors with a reduced pole count, and generally are

closed-loop commutated.)

10.1.1 BASICS OF OPERATION

Stepper motors operate differently from DC brush motors, which rotate when voltage is applied

to their terminals. Stepper motors, on the other hand, effectively have multiple "toothed"

electromagnets arranged around a central gear-shaped piece of iron. The electromagnets are

energized by an external control circuit, such as amicrocontroller.To make the motor shaft turn,

first one electromagnet is given power, which makes the gear's teeth magnetically attracted to the

electromagnet's teeth. When the gear's teeth are thus aligned to the first electromagnet, they are

slightly offset from the next electromagnet. So when the next electromagnet is turned on and the

first is turned off, the gear rotates slightly to align with the next one, and from there the process

is repeated. Each of those slight rotations is called a "step", with an integer number of steps

making a full rotation. In that way, the motor can be turned by a precise angle.

10.1.2 CHARACTERISTICS:

1. Stepper motors are constant power devices.

2. As motor speed increases, torque decreases. (most motors exhibit maximum torque when

stationary, however the torque of a motor when stationary 'holding torque' defines the

ability of the motor to maintain a desired position while under external load).
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3. The torque curve may be extended by using current limiting drivers and increasing the

driving voltage (sometimes referred to as a 'chopper' circuit; there are several off the

shelf driver chips capable of doing this in a simple manner).

4. Steppers exhibit more vibration than other motor types, as the discrete step tends to snap

the rotor from one position to another (called a detent). The vibration makes stepper

motors noisier than DC motors.

5. This vibration can become very bad at some speeds and can cause the motor to lose

torque or lose direction. This is because the rotor is being held in a magnetic field which

behaves like a spring. On each step the rotor overshoots and bounces back and forth,

"ringing" at its resonant frequency. If the stepping frequency matches the resonant

frequency then the ringing increases and the motor comes out of synchronism, resulting

in positional error or a change in direction. At worst there is a total loss of control and

holding torque so the motor is easily overcome by the load and spins almost freely.

6. The effect can be mitigated by accelerating quickly through the problem speeds range,

physically damping (frictional damping) the system, or using a micro-stepping driver.

7. Motors with a greater number of phases also exhibit smoother operation than those with

fewer phases (this can also be achieved through the use of a micro stepping drive)

10.1.3 TYPES OF STEPPER MOTORS

There are three basic types of step motors:

Variable reluctance

Permanent magnet,and

Hybrid

This discussion will concentrate on the hybrid motor, since these step motors combine the

best characteristics of the variable reluctance and permanent magnet motors. They are

constructed with multi-toothed stator poles and a permanent magnet rotor .Standard

hybrid motors (such as the models offered byOmegamationTM)have 200 rotor teeth and

rotate at 1.8 step angles. Because they exhibit high static and dynamic torque and run at
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very high step rates, hybrid step motors are used in a wide variety of commercial

applications including computer disk drives, printers/plotters, and CD players.

Some industrial and scientific applications of stepper motors include robotics, machine

tools, pick and place machines, automated wire cutting and wire bonding machines, and

even precise fluid control devices.

10.1.4 STEP MODES

Stepper motor "step modes" include Full, Half and Microstep. The type of step mode output of

any stepper motor is dependent on the design of the driver. Omegamationoffers stepper motor

drives with switch selectable full and half step modes, as well as microstepping drives with either

switch-selectable or software-selectable resolutions.

FULL STEP

Standard hybrid stepping motors have 200 rotor teeth, or 200 full steps per revolution of the

motor shaft. Dividing the 200 steps into the 360 of rotation equals a 1.8 full step angle.

Normally, full step mode is achieved by energizing both windings while reversing the current

alternately. Essentially one digital pulse from the driver is equivalent to one step.

HALF STEPHalf step simply means that the step motor is rotating at 400 steps per revolution. In this mode,

one winding is energized and then two windings are energized alternately, causing the rotor to

rotate at half the distance, or 0.9. Although it provides approximately 30% less torque, half-step

mode produces a smoother motion than full-step mode.

MICROSTEP

Microstepping is a relatively new stepper motor technology that controls the current in the motor

winding to a degree that further subdivides the number of positions between poles. Omegamation

microstepping drives are capable of dividing a full step (1.8) into 256 microsteps, resulting in

51,200 steps per revolution (.007/step). Microstepping is typically used in applications that

require accurate positioning and smoother motion over a wide range of speeds. Like the half-step

mode, microstepping provides approximately 30% less torque than full-step mode.


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10.1.5 HOW STEPPER MOTORS WORK

Stepper motors consist of a permanent magnet rotating shaft, called the rotor, and electromagnetson the stationary portion that surrounds the motor, called the stator. Figure 1 illustrates one

complete rotation of a stepper motor. At position 1, we can see that the rotor is beginning at the

upper electromagnet, which is currently active (has voltage applied to it). To move the rotor

clockwise (CW), the upper electromagnet is deactivated and the right electromagnet is activated,

causing the rotor to move 90 degrees CW, aligning itself with the active magnet. This process is

repeated in the same manner at the south and west electromagnets until we once again reach the

starting position.

Fig.10.1.5.1 Working of Stepper motor I

In the above example, we used a motor with a resolution of 90 degrees or demonstration

purposes. In reality, this would not be a very practical motor for most applications. The average

stepper motor's resolution -- the amount of degrees rotated per pulse -- is much higher than this.

For example, a motor with a resolution of 5 degrees would move its rotor 5 degrees per step,

thereby requiring 72 pulses (steps) to complete a full 360 degree rotation.


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You may double the resolution of some motors by a process known as "half-stepping". Instead of

switching the next electromagnet in the rotation on one at a time, with half stepping you turn on

both electromagnets, causing an equal attraction between, thereby doubling the resolution. As

you can see in Figure 2, in the first position only the upper electromagnet is active, and the rotor

is drawn completely to it. In position 2, both the top and right electromagnets are active, causing

the rotor to position itself between the two active poles. Finally, in position 3, the top magnet is

deactivated and the rotor is drawn all the way right. This process can then be repeated for the

entire rotation.

Fig. 10.1.5.2 Working of Stepper Motor II

There are several types of stepper motors. 4-wire stepper motors contain only two

electromagnets, however the operation is more complicated than those with three or four

magnets, because the driving circuit must be able to reverse the current after each step. For our

purposes, we will be using a 6-wire motor.

Unlike our example motors which rotated 90 degrees per step, real-world motors employ a series

of mini-poles on the stator and rotor to increase resolution. Although this may seem to add morecomplexity to the process of driving the motors, the operation is identical to the simple 90 degree

motor we used in our example. An example of a multipole motor can be seen in Figure 3. In

position 1, the north pole of the rotor's perminant magnet is aligned with the south pole of the

stator's electromagnet. Note that multiple positions are alligned at once. In position 2, the upper


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electromagnet is deactivated and the next one to its immediate left is activated, causing the rotor

to rotate a precise amount of degrees. In this example, after eight steps the sequence repeats.

The specific stepper motor we are using for our experiments (ST-02: 5VDC, 5 degrees per step)

has 6 wires coming out of the casing. If we follow Figure 5, the electrical equivalent of the

stepper motor, we can see that 3 wires go to each half of the coils, and that the coil windings are

connected in pairs. This is true for all four-phase stepper motors.

Fig.10.1.5.3 Four Phase Stepper motor


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However, if we do not have an equivalent diagram for the motor you want to use, you can make

a resistance chart to decipher the mystery connections. There is a 13 ohm resistance between the

center-tap wire and each end lead, and 26 ohms between the two end leads. Wires originating

from separate coils are not connected, and therefore would not read on the ohm meter.

10.2 VOLTAGE REGULATOR (7805)

The voltage regulator regulates the supply if the supply if the line voltage increases or decreases.

The series 78xx regulators provide fixed regulated voltages from 5 to 24 volts. An unregulated

input voltage is applied at the IC Input pin i.e. pin 1 which is filtered by capacitor. The out

terminal of the IC i.e. pin 3 provides a regular output. The third terminal is connected to ground.

While the input voltage may vary over some permissible voltage range, and the output voltage

remains constant within specified voltage variation limit. The 78xx ICs are positive voltage

regulators whereas 79xx ICs are negative voltage regulators.

These voltage regulators are integrated circuits designed as fixed voltage regulators for a wide

variety of applications. These regulators employ current limiting, thermal shutdown and safe area

compensation. With adequate heat sinking they can deliver output currents in excess of 1 A.

These regulators have internal thermal overload protection. It uses output transistor safe area

compensation and the output voltage offered is in 2% and 4% tolerance.

10.2.1 FEATURES

Output Current up to 1A

Output Voltages of 5, 6, 8, 9, 10, 12, 15, 18, 24V

Thermal Overload Protection

Short Circuit Protection

Output Transistor Safe Operating Area Protection


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Fig.10.2.1. Pin Diagram Of Voltage Regulator 7805

The 78xx (sometimes LM78xx) is a family of self-contained fixedlinear voltage

regulatorintegrated circuits.The 78xx family is commonly used in electronic circuits requiring a

regulated power supply due to their ease-of-use and low cost. For ICs within the family, the xx is

replaced with two digits, indicating the outputvoltage (for example, the 7805 has a 5 volt output,

while the 7812 produces 12 volts). The 78xx line are positive voltage regulators: they produce a

voltage that is positive relative to a common ground. There is a related line of 79xx devices

which are complementary negative voltage regulators. 78xx and 79xx ICs can be used in

combination to provide positive and negative supply voltages in the same circuit. 78xx ICs have

three terminals and are commonly found in theTO220 form factor, although smaller surface-
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mount and largerTO3packages are available. These devices support an input voltage anywhere

from a couple of volts over the intended output voltage, up to a maximum of 35 or 40 volts, and

typically provide 1 or 1.5amperes ofcurrent (though smaller or larger packages may have a

lower or higher current rating)

10.3 THE IR LIGHT EMITTER

10.3.1 PRINCIPLE OF OPERATION

Because they emit at wavelengths which provide a close match to the peak spectral response of

silicon photodetectors, both GaAs and GaAlAs. In general, there are four characteristics of IR

emitters that designers have to take care of:

Rise and Fall Time

Emitter Wavelength

Emitter Power

Emitter Half-angle

Fig.10.3.1 Wavelength vs. Radiant Power
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10.3.2 DESCRIPTION

In this system IR LED used is QED233 / QED234 which is a 940 nm GaAs / AlGaAs LED

encapsulated in a clear untinted, plastic T-1 3/4 package.

IR Led LED Schematic

Fig.10.3.2 IR LED Schematic Diagram

10.3.3 QED234 FEATURES

Wavelength=940nm

Chip material =GaAs with AlGaAs window.

Medium Emission Angle, 40

High Output Power

Package material and color: Clear, untinted, plastic

Ideal for remote control applications.

ANODE CATHODEE


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10.4 IR LIGHT DETECTOR

The most common device used for detecting light energy in the standard data stream is a

photodiode. Photo transistors are not typically used in IrDA standard-compatible systems

because of their slow speed. Photo transistors typically have ton/toff of 2 s or more. A photo

transistor may be used, however, if the data rate is limited to 9.6 kb with a pulse width of 19.5

s. A photodiode is packed in such a way so as to allow light to strike the PN junction. In

infrared applications, it is common practice to apply a reverse bias to the device. There will be a

reverse current that will vary with the light level. Like all diodes, there is an intrinsic capacitance

that varies with the reverse bias voltage. This capacitance is an important factor in speed.

10.4.1 DESCRIPTION

The QSE973 is a silicon PIN photodiode encapsulated in an infrared transparent, black, plastic

T092 package.

IR Photodiode Reverse Bias Photodiode

Fig.10.4.1 IR Photo diode

10.4.2 QSE 973 FEATURES

Daylight filter

T092 package

PIN photodiode

Recepting angle 90

Chip size = .1072 sq. inches (2.712 sq. mm)

1 2

+

_

A

Cathode


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Link Distance

To select an appropriate IR photo-detect diode, the designer must keep in mind the distance of

communication, the amount of light that may be expected at that distance and the current that

will be generated by the photodiode given a certain amount of light energy. The amount of light

energy, or irradiance that is present at the active-input interface is typically given in W/cm2.

10.5 LIQUID CRYSTAL DISPLAY

A liquid crystal display (LCD) is aflat panel display,electronic visual display,orvideo display

that uses the light modulating properties ofliquid crystals (LCs). LCs do not emit light

directly.LCDs are used in a wide range of applications, includingcomputer monitors,television,

instrument panels,aircraft cockpit displays,signage,etc. They are common in consumer devicessuch as video players, gaming devices,clocks,watches,calculators,andtelephones.LCDs have

replacedcathode ray tube (CRT) displays in most applications. They are available in a wider

range of screen sizes than CRT andplasma displays,and since they do not use phosphors, they

cannot suffer image burn-in. LCDs are, however, susceptible toimage persistence.[1]The LCD is

more energy efficient and offers safer disposal than a CRT. Its low electrical power consumption

enables it to be used inbattery-poweredelectronic equipment. It is anelectronically modulated

optical device made up of any number of segments filled withliquid crystals and arrayed in front

of alight source (backlight)orreflector to produce images in color ormonochrome.The most

flexible ones use an array of smallpixels.
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10.5.1 BLOCK DIAGRAM

Fig.10.5.1 Block Diagram of LCD

.10.5.2 OVERVIEW

Eachpixel of an LCD typically consists of a layer ofmolecules aligned between twotransparent

electrodes,and twopolarizingfilters,the axes of transmission of which are (in most of the cases)

perpendicular to each other. With no actualliquid crystalbetween the polarizing filters,light

passing through the first filter would be blocked by the second (crossed) polarizer.

The surface of the electrodes that are in contact with the liquid crystal material are treated so as

to align the liquid crystal molecules in a particular direction. This treatment typically consists of

a thinpolymer layer that is unidirectionally rubbed using, for example, a cloth. The direction of

the liquid crystal alignment is then defined by the direction of rubbing. Electrodes are made of

the transparent conductorIndium Tin Oxide (ITO). The Liquid Crystal Display is intrinsically a

passive device, it is a simple light valve. The managing and control of the data to be displayed

is performed by one or more circuits commonly denoted as LCD drivers.
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Before applying anelectric field,the orientation of the liquid crystal molecules is determined by

the alignment at the surfaces of electrodes. In a twisted nematic device (still the most common

liquid crystal device), the surface alignment directions at the two electrodes are perpendicular to

each other, and so the molecules arrange themselves in ahelical structure, or twist. This induces

the rotation of the polarization of the incident light, and the device appearsgrey.If the applied

voltage is large enough, the liquid crystal molecules in the center of the layer are almost

completely untwisted and the polarization of theincident light is not rotated as it passes through

the liquid crystal layer. This light will then be mainly polarizedperpendicular to the second

filter, and thus be blocked and thepixel will appearblack.By controlling the voltage applied

across the liquid crystal layer in each pixel, light can be allowed to pass through in varying

amounts thus constituting different levels of gray.

The optical effect of a twisted nematic device in the voltage-on state is far less dependent on

variations in the device thickness than that in the voltage-off state. Because of this, these devices

are usually operated between crossed polarizers such that they appear bright with no voltage (the

eye is much more sensitive to variations in the dark state than the bright state). appears blotchy,

however, because of small variations of thickness across the device.

Both the liquid crystal material and the alignment layer material containionic compounds.If an

electric field of one particular polarity is applied for a long period of time, this ionic material is

attracted to the surfaces and degrades the device performance. This is avoided either by applying

analternating current or by reversing the polarity of the electric field as the device is addressed

(the response of the liquid crystal layer is identical, regardless of the polarity of the applied

field).

Displays for a small number of individual digits and/or fixed symbols (as indigital watches,

pocket calculators etc.) can be implemented with independent electrodes for each segment. In

contrast fullalphanumeric and/or variable graphics displays are usually implemented with pixels

arranged as a matrix consisting of electrically connected rows on one side of the LC layer and

columns on the other side, which makes it possible to address each pixel at the intersections. The

general method of matrix addressing consists of sequentially addressing one side of the matrix,
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for example by selecting the rows one-by-one and applying the picture information on the other

side at the columns row-by-row.

10.6 ULN2003

Fig.10.6 Apperance of an ULN2003 IC

10.6.1 DESCRIPTION

The ULN2001A, ULN2002A, ULN2003 and ULN2004A are high voltage, high current

darlington arrays each containing seven open collector darlington pairs with common emitters

Fig.10.6.1 Pin Description of ULN2003


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Each channel rated at 500mA and can withstand peak currents of 600mA.

The four versions interface to all common logic families

:

These versatile devices are useful for driving a wide range of loads including solenoids, relays

DC motors, LED displays filament lamps, thermal printheads and high power buffers. The

ULN2001A/2002A/2003A and 2004A are supplied in 16 pin plastic DIP packages with a copper

leadframe to reduce thermal resistance. They are available also in small outline package (SO-16)

as ULN2001D/2002D/2003D/2004D


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10.7 OPERATIONAL AMPLIFIER

10.7.1 PIN DIAGRRAM:

Fig. 10.7.1 Pin Diagram of Operational Amplifier

10.7.2 DESCRIPTION

These circuits consist of four independent, high gain, internally frequency compensated

operational amplifiers. They operate from a single power supply over a wide range of voltages.

Operation from split power supplies is also possible and the low power supply current drain is

independent of the magnitude of the power supply voltage.

Fig.10.7.2 Internal Connections of Operational amplifier


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The operational amplifier LM324N is the 14 pin dip, internally it consists of four op amplifier

working independently of each other. Single op amplifier consists of 2 inputs (inverting and non

inverting ) and single output. The Pin 4 and Pin 11 are connected to the Vcc and on the upper

and lower end op amplifiers are connected.

Applications include transducer amplifiers, dc amplification blocks, and all the conventional

operational amplifier circuits that now can be more easily implemented in single-supply-voltage

systems. For example, the LM124 can be operated directly from the standard 5-V supply that is

used in digital systems and easily provides the required interface electronics without requiring

additional 15-V supplies.

The LM2902Q is manufactured to demanding automotive requirements.

The LM124 and LM124A are characterized for operation over the full military temperature

range of55C to 125C. The LM224 and LM224A are characterized for operation from25C

to 85C. The LM324 and LM324A are characterized for operation from 0C to 70C. The

LM2902 and LM2902Q are characterized for operation from40C to 125C.


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CHAPTER 11

PROJECT CODE

11.1 TRANSMITTER MICROCONTROLLER CODE

$include(mod51);-------------------------------------------------------------deg1 equ 21deg2 equ 22deg3 equ 23deg4 equ 24

org 000hljmp main

org 00ffh

main:

lcall inzdata

clr p2.1

mov r4, #12main1: lcall move_moter

lcall sendlcall delay

ljmp main1

;--------------------------------------------------------------

send: mov sbuf, a

back: jnb ti, backclr tiret

;--------------------------------------------------------------move_moter: mov p0, #0fh

lcall showdatalcall delaylcall check_ir


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mov p0, #0fchlcall showdatalcall delaylcall check_ir

mov p0, #0f6hlcall showdatalcall delaylcall check_ir


djnz r4, move_moter

mov r4, #12

anticlk: nop

agn3: mov p0, #0f3hlcall showdata2lcall delaylcall check_ir

mov p0, #0f6h

lcall showdata2lcall delaylcall check_ir

mov p0, #0fchlcall showdata2lcall delaylcall check_ir

mov p0, #0f9hlcall showdata2lcall delay

lcall check_irdjnz r4, agn3mov r4, #12ljmp move_moter

showdata:mov r3, #4bh


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k:

inc deg4mov a, deg4cjne a, #3ah, h1

mov deg4, #30hinc deg3

h1: mov a, deg3cjne a, #3ah, h2mov deg3, #30hinc deg2

h2: mov a, deg2cjne a, #3ah, h3mov deg2, #30hinc deg1

h3: mov a, deg1cjne a, #3ah, h4

mov deg1, #30h

h4: djnz r3, kret

;------------------------------------------

showdata2:

mov r3, #4bhagain:

dec deg4

mov a, deg4cjne a, #2fh, g1mov deg4, #39hdec deg3

g1: mov a, deg3cjne a, #2fh, g2mov deg3, #39hdec deg2


g3: mov a, deg1cjne a, #2fh, g4mov deg1, #39h

g4: djnz r3, again

ret


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;---------------------------------------------

check_ir: jb p2.0, send_dret

send_d: mov a, deg1lcall sendlcall delayb

mov a, deg2lcall sendlcall delayb



w8_command: jnb ri, w8_commandclr ri

see1: mov a, sbufcjne a, #01h, see2setb p2.1

see2: cjne a, #02h, see3clr p2.1

see3: cjne a, #03h, w8_command

ret

;----------------------------------------------------------------------

delayb: mov r5, #02hl31: mov r1, #0fhl21: mov r2, #0ffhl11: djnz r2, l11

djnz r1, l21


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djnz r5, l31ret

;---------------------------------------------------------

delay:mov r1, #80h

l2: mov r2, #0ffhl1: djnz r2, l1

djnz r1, l2

ret

;-----------------------------------------------------------------

inzdata: mov tmod, #20hmov th1, #0fdhmov scon, #50hsetb tr1

mov deg1, #30hmov deg2, #30hmov deg3, #30hmov deg4, #30hret

end


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11.2 RECEIVER MICROCONTROLLER CODE

$include(mod51);-------------------------------------------------------------deg1 equ 21

deg2 equ 22deg3 equ 23deg4 equ 24

org 000hljmp main

org 00ffh

main:

lcall inzdata

clr p2.1

mov r4, #12main1: lcall move_moter

lcall send

lcall delay

ljmp main1

;--------------------------------------------------------------

send: mov sbuf, aback: jnb ti, back

clr tiret

;--------------------------------------------------------------

move_moter: mov p0, #0fhlcall showdatalcall delaylcall check_ir

mov p0, #0fchlcall showdatalcall delaylcall check_ir


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djnz r4, move_moter

mov r4, #12

anticlk: nop

agn3: mov p0, #0f3hlcall showdata2lcall delaylcall check_ir

mov p0, #0f6hlcall showdata2lcall delaylcall check_ir

mov p0, #0fch

lcall showdata2lcall delaylcall check_ir

mov p0, #0f9hlcall showdata2lcall delaylcall check_irdjnz r4, agn3mov r4, #12ljmp move_moter

showdata:mov r3, #4bh

k:

inc deg4mov a, deg4


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cjne a, #3ah, h1mov deg4, #30hinc deg3

h1: mov a, deg3cjne a, #3ah, h2mov deg3, #30h

inc deg2h2: mov a, deg2

cjne a, #3ah, h3mov deg2, #30hinc deg1

h3: mov a, deg1cjne a, #3ah, h4mov deg1, #30h

h4: djnz r3, kret

;------------------------------------------

showdata2:

mov r3, #4bhagain:

dec deg4mov a, deg4cjne a, #2fh, g1mov deg4, #39hdec deg3

g1: mov a, deg3

cjne a, #2fh, g2mov deg3, #39hdec deg2


g3: mov a, deg1cjne a, #2fh, g4mov deg1, #39h

g4: djnz r3, again

ret

;---------------------------------------------

check_ir: jb p2.0, send_d


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ret

send_d: mov a, deg1lcall sendlcall delayb




w8_command: jnb ri, w8_commandclr ri

see1: mov a, sbufcjne a, #01h, see2setb p2.1

see2: cjne a, #02h, see3clr p2.1

see3: cjne a, #03h, w8_command

ret

;----------------------------------------------------------------------

delayb: mov r5, #02h

l31: mov r1, #0fhl21: mov r2, #0ffhl11: djnz r2, l11

djnz r1, l21djnz r5, l31ret


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;---------------------------------------------------------

delay:mov r1, #80h

l2: mov r2, #0ffhl1: djnz r2, l1

djnz r1, l2

ret

;-----------------------------------------------------------------

inzdata: mov tmod, #20hmov th1, #0fdhmov scon, #50hsetb tr1

mov deg1, #30hmov deg2, #30hmov deg3, #30hmov deg4, #30hret

end


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CHAPTER 12

CONCLUSION

ADVANTAGES:

1. It is used in military purposes for detection of unknown objects.

2. It is used to locate ground and sea targets.

3. It is used for weather forecasting.

4. It is used in aircraft system,aircraft are equipped with radar devices that warn of obstacles in

their path and give accurate altitude readings.

LIMITATIONS:

1.The IR sensor used in our project is of low range. Although this limitation can be easily

overcome .The range can be increased by using Costly sensors or UV sensor.

CONCLUSION:

A lot of further developments can be done in this field. Radar is avastly emerging field being

used for a variety of applications already and there is a lot of scope for creating a variety of such

projects using the various omponents like Zig-bee and other microcontrollers.


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BIBLIOGRAPHY

1.Wikipedia.

2.Merrill Ivan Skolnik (1980-12-01). Introduction to radar systems.

3.Merrill Ivan Skolnik (1990). Radar handbook. McGraw-Hill Professional.

4.Microcontroller by Mazidi, Pearson Publication

radar project

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