These radars were of the type that later became known as 'Primary' radars. The reflected signal is also-called scattering.

Primary radar operation is based on the principle of echolocation. This type of radar uses low vertical resolution antenna but good horizontal resolution. The radar antenna illuminates the target with a microwave signal, which is then reflected

and picked up by a receiving device. The term “RADAR” was officially coined as an acronym by U.S. Navy Lieutenant Commander Samuel M. Tucker and F. R. Furth in November 1940. Radar was born in the due to the pressure of war. Under some conditions, radar system can measure the direction, height, distance, course, and speed of these objects. In addition, it requires powerful emissions which limits its scope. The advantages of the primary radar are no on-board equipment in the aircraft is necessary for detecting the target and can be used to monitor the movement of vehicles on the ground. The following figure shows the operating principle of a primary radar set.

This is reflected by the aircraft and then picked up again by the rotating antenna on its own axis. If you know the speed of sound in air, you can then estimate the distance and general direction of the object.

It can be said that a radar locates a flying object on a quarter circle in the vertical plane, but cannot know exactly its altitude if it is using a The rapid wartime development of radar had obvious applications for When primary radar was the only type of radar available, the correlation of individual radar returns with specific aircraft typically was achieved by the controller observing a directed turn by the aircraft. The electronic principle on which radar operates is very similar to the principle of sound-wave reflection. That is, they worked on the well-known 'Battle of Britain' principle in which the radar transmitter sends out a pulse of radio energy, of which a very small proportion is reflected from the surface or structure of the target aircraft back to the radar … aircraft. Unit No. Radar sets use the echo to determine the

The need to detect “hostile” aircraft led to a vast investment in intellect and money to develop RADAR.Classical Radar (now called Primary Radar) by definition is a non co-operative technology, that is it needs … But the calculating of the range by measuring the delay time is one of its most important functions.

Primary radar operation is based on the principle of echolocation.

Modern radar can extract widely more information from a target's echo signal than its range. This permits radar systems to determine the position of airplanes, ships, or other obstacles that are invisible to the naked eye because of distance, darkness, or weather.Modern radar can extract widely more information from a target's echo signal than its range. This returned energy is called an ECHO, just as it is in sound terminology. The radars used by police to catch speeders actually operate more or less along such a principle, though their implementation is much more sophisticated and they will actually give speed readings. The electrical signal picked up by the receiving

8540287 Continuation 3 (c) Practical factors restricting the …

Basic Principles The basic principle of radar operation is simple to understand. Electromagnetic pulses of high power emitted by the radar antenna are converted into a narrow wavefront which propagates at the speed of light (300 000 000 m/s). But the calculating of the range by measuring the delay time is one of its most important functions.The following figure shows the operating principle of a primary radar set. If you shout in the direction of a sound-reflecting object (like a rocky canyon or cave), you will hear an echo. Electromagnetic pulses of high power emitted by the radar antenna are converted into a narrow wavefront which propagates at the speed of light (300 000 000 m/s).

Therefore, it performs transmission/listening continuously, which covers the space 360 °. Figure-1 depicts primary radar principle of operation. and received by a highly sensitive receiver.All targets produce a diffuse reflection i.e. 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. Primary radar is still used by ATC today as a backup/complementary system to secondary radar, although its coverage and information is more limited.ITU Radio Regulations, Section IV. The disadvantages are that the target and altitude can not be identified directly.

The theory behind radar, on the other hand, is very complex. It refers to electronic equipment that detects the presence of objects by using reflected electromagnetic energy. 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. Radar signals can be displayed on the traditional The acronym was by agreement adopted in 1943 by the Allied powers of World War II and thereafter received general international acceptance. It can thus give the distance and radial speed of the target with good precision but requires often one or more radars to obtain the vertical position and the actual speed. The radar signal is generated by a powerful transmitter The aircraft acts as passive element and reflects the EM energy back towards the primary radar antenna. This is reflected by the aircraft and then picked up … (b) Calculations dete rmining radar range are correctly performed. A primary radar detects all aircraft without selection, regardless of whether or not they possess a transponder.The operator hears the echoes from any reflection. THE PRINCIPLES OF A PRIMARY RADAR SYSTEM PERFORMANCE CRITERIA (a) The characteristics of radar pulses are correctly determined. it is reflected in a wide number of directions. As shown, Primary Surveillance Radar (PSR) transmits electromagnetic signal energy towards the target i.e. A radar system transmits electromagnetic energy and analyzes the energy reflected back to it (by an object). Basic design of radar system. The primary radar functions, therefore, results in detection and measurements of position if there is the presence of a target by the recognition of the useful signal.