RADAR System Anas Abu Siam

Introduction RADAR Is a device or system for detecting and locating a target by radio waves. The term RADAR was coined in 1940 by the United States Navy as an acronym for RA dio D etection A nd R anging.

The Idea 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. Radar uses electromagnetic power pulses in much the same way.

Functions Of RADAR 1.Target Range ( Distance ). 2.Target Angels ( Horizontal & Vertical ). 3.Target Size. 4.Target Speed.

1. Target Range Radar measurement of range, or distance, is made possible because of the properties of radiated electromagnetic energy. This energy normally travels through space in a straight line, at a constant speed : C = 3*10 8

1. Target Range Duty Cycle = τ / T T : time repetition interval τ : pulse width

1. Target Range Final equation to find the range : Distance = C *T R /2

Functions Of RADAR 1.Target Range ( Distance ). 2.Target Angels ( Horizontal & Vertical ). 3.Target Size. 4.Target Speed.

2. Target Angels Elevation Azimuth

2. Target Angels There are two methods to estimate the angels: I.Mechanical ( Motor ) :

2. Target Angels II. Array of Antenna :

Functions Of RADAR 1.Target Range ( Distance ). 2.Target Angels ( Horizontal & Vertical ). 3.Target Size. 4.Target Speed.

3. Target Size I.Magnitude of return. II.Radar Cross Section (RCS) : is a virtual area representing the intensity of the reflection.

4. Target Speed Doppler Effect : Frequency shift is caused by motion that changes the number of wavelengths between the reflector and the radar. That can degrade or enhance radar performance depending upon how that affects the detection process.

RADAR as a System Duplexer TransmitterReceiver ProcessingDisplay Antenna

Display

Radar Types By the number of antennas : – MonoStatic : Single Antenna – BiStatic : Two Antennas – MultiStatic : More than 2 Antennas By Scan Strategy : – Pulse RADAR – Continuous Wave RADAR By Source of the power : – Active Radar – Passive Radar

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