A Report on Radar System

A REPORT ON RADAR SYSTEM

Nnaemeka Nweke | Telecommunications Technology | March 19, 2014

THIS IS TO CERTIFY THAT THIS REPORT IS THE ORIGINAL WORK OF;

NAMES

REG. NUMBER

NWEKE FRANK NNAEMEKA

20101742916

(GROUP LEADER)

BECHEM COLLINS TABE

20101713336

BENSON FRANCIS

20101766106

KADURU EMEKA. A

20101729696

AMANDE EMEKA. F

20101742776

OFOEGBU CHRISTOPHER

20101753176

GEORGE WALTER

20101729646

UBADINMA CLEMENTINA

20101753256

NWANEGBO ONYEKA. G

20101725664

ANYOGU PETER TOCHUKWU

20101713316

A Report on Radar System, Federal University of Technology Owerri.

March 19, 2014

1

INTRODUCTION

Radar (acronym for Radio Detection and Ranging) is an object-detection system that uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio waves or microwaves that bounce off any object in their path. The object returns a tiny part of the wave's energy to a dish or antenna that is usually located at the same site as the transmitter. Radar was secretly developed by several nations before and during World War II. The term RADAR itself, not the actual development, was coined in 1940 by the United States Navy as an acronym for Radio Detection and Ranging .[1][2] The term radar has since entered English and other languages as the common noun radar, losing all capitalization. The modern uses of radar are highly diverse, including air traffic control, radar astronomy, air-defense systems, antimissile systems ; marine radars to locate landmarks and other ships; aircraft anti-collision systems; ocean surveillance systems, outer space surveillance and rendezvous systems; meteorological precipitation monitoring; altimetry and flight control systems; guided missile target locating systems; and ground-penetrating radar for geological observations.

A Report on Radar System, Federal University of Technology Owerri.

March 19, 2014

2

CHAPTER ONE

THE PRINCIPLE OF THE SECONDARY SURVILLIENCE RADAR SYSTEM AS USED IN AIR TRAFFIC CONTROL (ATC). The following Air Traffic Control (ATC) surveillance, approach and landing radars are commonly used in Air Traffic Management (ATM): 

en-route radar systems,



Air Surveillance Radar (ASR) systems,



Precision Approach Radar (PAR) systems,



Surface movement radars, and



Special weather radars.

EN ROUTE RADARS En-route radar systems operate in L-Band usually. This radar sets initially detect and determine the position, course, and speed of air targets in a relatively large area up to 250 nautical miles (NM).

A typically en-route radar Air Surveillance Radar (ASR)

A Report on Radar System, Federal University of Technology Owerri.

March 19, 2014

3

Airport Surveillance Radar (ASR) is approach control radar used to detect and display an aircraft's position in the terminal area. These radar sets Operate usually in EBand, and are capable of reliably detecting and tracking aircraft at altitudes below 25,000 feet (7,620 meters) and within 40 to 60 nautical miles (75 to 110 km) of their airport.

ASR-12 A typically Air Surveillance.

PRECISION APPROACH RADAR (PAR) The ground-controlled approach is a control mode in which an aircraft is able to land in bad weather. The pilot is guided by ground control using precision approach radar. The guidance information is obtained by the radar operator and passed to the aircraft by either voice radio or a computer link to the aircraft.

A Report on Radar System, Federal University of Technology Owerri.

March 19, 2014

4

A typical diagram of PAR.

SURFACE MOVEMENT RADAR (SMR) The Surface Movement Radar (SMR) scans the airport surface to locate the positions of aircraft and ground vehicles and displays them for air traffic controllers in bad weather. Surface movement radars operate in J- to Xband and uses an extremely short pulse-width to provide an acceptable range-resolution. SMR are part of the Airport Surface Detection Equipment (ASDE).

SPECIAL WEATHER-RADAR APPLCATION Weather radar is very important for the air traffic management. There are weatherradars specially designed for the air traffic safety.

A Report on Radar System, Federal University of Technology Owerri.

March 19, 2014

5

PRINCIPLES OF OPERATION The interrogator on the ground transmits coded pulses with different modes. Every mode represents a different question. For conventional SSR the choice of question is very simple. The controller wants to identify of the aircraft (‘WHO ARE YOU’). The Radar gives a two dimensional position fix of the aircraft, but air traffic control is very much a three dimensional positional fix. These different determine the MODE of operation. The aircrafts transponder reply with a CODE. The chosen mode is encoded in the coder. (By the different modes different questions can be defined to the airplane). The transmitter modulates these coded impulses with the RF frequency. Because another frequency than on the replay path is used on the interrogation path, an expensive duplexer can be renounced. The antenna is usually mounted on the antenna of the primary radar unit and turns synchronously to the deflection on the monitor-frequency.

The diagram of the following operated principle is below;

A Report on Radar System, Federal University of Technology Owerri.

March 19, 2014

6

CHAPTER TWO RELATED SIGNAL PROCESSING SCHEME

Signal processing is an area of systems engineering, electrical engineering and applied mathematics that deals with operations or analysis of analog as well as digitized signals, representing time –varying or spatially physical quantities. There are some other signals processing namely: 

Digital signal processing



Nonlinear signal processing



Analog signal processing



Discrete signal processing

A Report on Radar System, Federal University of Technology Owerri.

March 19, 2014

7

NONLINEAR SIGNAL PROCESSING

It involves the analysis and processing of signals produces from nonlinear system and can be in the time, frequency, or spatio- temporal domain. Nonlinear system can produce highly complex behavior including (Bifurcations, chaos, harmonics, and sub harmonic) which cannot be produced or analyzed using linear methods.

DIGITAL SIGNAL PROCESSING In digital signal processing is of digitized discrete-time sampled signal. Processing is done by general purpose computer or by digital circuits such as ASIC, field programmable gate arrays processor. The typical operation includes fixed- point and floating-point, real valued and complex valued multiplication and addition. Other typical operation supported are circular buffers and look up tables examples of algorithms are (FFT) finite impulse response (FIR) filters and adaptive filters such as the wiener and kalman filters and infinite impulse response (IIR).

DESCRETE-TIME SIGNAL PROCESSING It is for sampled signal defined only at discrete point in time but not in magnitude. Analog discrete-time signal processing s a technology based on electronics devices such as (sample and hold circuit, analog time division multiplexers, analog delay lines and analog feedback shift register).this technology was a predecessor of digital signal processing.

ANALOG SIGNAL PROCESSING This is for signal that has not been digitalized, as in legacy radio, telephone, radar, and television systems. This involves linear electronic circuits as well as non-linear ones. The former are for instance (passive filters, active filters, additive filters and delay lines) while non-linear circuits include compandors, multiplicators, frequency mixers and voltage –controlled oscillators and phase- cocked loops.

A Report on Radar System, Federal University of Technology Owerri.

March 19, 2014

8

CHAPTER THREE

FUNCTIONS OF THE VARIOUS BLOCKS OF MONOSTATIC PULSE RADAR

ANTENNA SYSTEM It transfers the transmitter energy to signals in space with the required distribution and efficiency. This process is applied in an identical way on reception. INDICATOR It produces a visual indication of the echo pulses in a manner That, at a minimum, furnishes range and bearing information RECEIVER It amplifies the weak; electromagnetic pulses returned from the reflecting object and reproduce them as video pulses that are sent to the indicator. DUPLEXER SYSTEM: - It allows the antenna to be used for transmitting and receiving. Timer: - it supplies the synchronizing signal that time the transmitter pulses, the indicator, & other associated circuits. TRANSMITTER: - This generates electromagnetic energy in the form of short, powerful pulses.

A Report on Radar System, Federal University of Technology Owerri.

March 19, 2014

9

CHAPTER FOUR A LINK BUDGET OF A SATELLITE SYSTEM The link budget determines the antenna size to deploy, power requirements, link availability, bit error rate, as well as the overall customer satisfaction with the satellite service. A link Budget is a tabular method for evaluating the power received and the noise ratio in a radio link. The following table for link budget may be implemented Feature

Data

Results

Unit

Maximum Distance

1160

Transmission Power

25

KM dbm

Transmission Loss

1

dB

Transmission Antenna Gain

4,5

dB

EIRP

30,5

dB

Free Space Loss

161,47

dB

Atmospheric Absorption

1

dB

Polarization Loss

3

dB

Antenna Misalignment Loss

1

dB

Propagation Loss

166,47

dB

Satellite Antenna Gain

35

dB

System Noise Temperature

110,11

K

Figure of Merit Boltzmann Constant

14,59 -228,6

Pr/N0 Bit Rate

Db/k/Hz 77,22

9600

Eb/N0 10-5

Eb/N0 @ 10-5

9,6

Downlink Margin

A Report on Radar System, Federal University of Technology Owerri.

dBHz Bit/s

37,4

BER

Db/K

dB

dB 27,8

dB

March 19, 2014

10

SUMMARY

In conclusion, radar is something that is used all around us even though it is normally invisible. When people use radar, they are usually trying to accomplish one of three things; detecting the presence of an object at a distance, detect the speed of an object, or to map something. All three of these activities can be accomplished simply by using echo and Doppler shift. These two concepts are easy to understand because your ear hears echo and Doppler shift every day. Radar makes use of the same techniques using radio waves. One particular usage of this radar technology is for transportation purposes. For many people, speeding is a normal part of daily life. This law bending is so common and also so accepted that there is even a special electronic equipment to help drivers get away with it. Since their introduction in 1970s by Mike Churchman, radar detectors have become a must have accessories for high-speed drivers. To understand how radar detector work, you first have to know what they are detecting.

A Report on Radar System, Federal University of Technology Owerri.

March 19, 2014

11

REFRENCE Mir, H. S., and J. D. Wilkinson, “Radar Target Resolution Probability in a Noise-Limited Environment,” IEEE Transactions on Aerospace and Electronic Systems, vol. 44(3), pp. 1234–1239, July 2008. Morris, G. V., and L. Harkness (eds.), Airborne Pulsed Doppler Radar, 2d ed. Artech House, Boston, MA, 1996. Nathanson, F. E., (with J. P. Reilly and M. N. Cohen), Radar Design Principles, 2d edition. McGraw-Hill, New York, 1991. Nitzberg, R., Radar Signal Processing and Adaptive Systems, 2d ed. Artech House, Boston, MA, 1999. Oppenheim, A. V., and R. W. Schafer, Discrete-Time Signal Processing, 2d ed. Prentice Hall, Englewood Cliffs, NJ, 1999. Papoulis, A., The Fourier Integral and Its Applications, 2d ed. McGraw-Hill, New York, 1987. Peebles, Jr., P. Z., Radar Principles. Wiley, New York, 1998. Richards, M. A., J. A. Scheer, and W. A. Holm (eds.), Principles of Modern Radar: Basic Principles. SciTech Publishing, Raleigh, NC, 2010. Scheer, J. A. and W. L. Melvin (eds.), Principles of Modern Radar: Radar Applications. SciTech Publishing, Edison, NJ, to appear 2014. Sherman, S. M., Monopulse Principles and Techniques. Artech House, Boston, MA, 1984. Skolnik, M. I., Introduction to Radar Systems, 3d ed. McGraw-Hill, New York, 2001. Soumekh, M., Synthetic Aperture Radar Signal Processing with MATLAB Algorithms. J. Wiley, New York, 1999.

A Report on Radar System, Federal University of Technology Owerri.

March 19, 2014

12