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Radar and How It Tracks An Aircraft

 

The key to track the position of an aircraft is using a radar system. Though this system has been used before the Second World War, improvement on the device has been constantly done even until now. RADAR is an acronym for Radio Detection and Ranging. It is made up of a transmitted radio signal with an accompanying antenna which is fixed in a particular direction, and a receiver that catches the echoes of the objects along the path of the signal.

 

The transmitter has an electronic circuit which oscillates at a much higher frequency, higher than the radio and TV frequencies. When the radar is in operation, a signal is transmitted in short bursts of electromagnetic energy, known as pulses, through the antenna which, consequently, produces a narrow beam-like torch. With that principle, a radar makes it possible to determine the direction to a target object by basing on the direction where the antenna is facing. The distance to the target object is measured from the time that transpired between transmitting the pulse and receiving the echo. The measurement is accurately determined because the radar signal travels at the speed of light, which is a universal physical constant.

 

For flightradar kostenlos control radars, the beam is fan-shaped, narrow in horizontal direction, wide in the vertical direction, so designed to accommodate high-altitude flying planes. This beam scans in a circular path once every two or three seconds and echoes are displayed on a plan-position indicator. It is the duty of the air traffic controller or a computer to track the echoes or sometimes referred to as blips on the position indicator to find out where an aircraft is heading. This procedure is called primary radar. Although primary radar is no longer used due to the reality that there are just too many planes in the sky, which is making it difficult for tracking with this kind of radar. Therefore, airports now used secondary radars, where a coded pulse sequence is transmitted to the aircraft, and a transponder in the plane generates a coded return, which actually stores a lot of information about the aircraft. While the secondary radar is utilized to track commercial aircraft, the primary radar is used in cases where there are no transponders in the plane or are turned off or broken. If the transponder is turned off, more likely, it will be difficult for air traffic controllers to detect which one among the blips correspond to the specific aircraft where the transponder is off.

 

When an aircraft flies low enough, below the flightradar 24 radar reach, the beam will hardly effect an illumination and the illumination range that can be seen is limited. The usual problem of radar for long distance operation is that the amount of transmitted power needed to send and receive the signal is dependent on the distance to the aircraft. Which further means, if the range is doubled to detect an aircraft, the amount of power must be increased by a factor of 16. This predicament has been solved by developing phases of arrays which consist of large numbers of small transmitters and receivers located on a planar surface so both operate in unison and the pulse compression, which generates longer and lower power encoded pulses, are detected in a good range of accuracy.

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