what is radar?

Radar: Radar is formed by combining the initial letters of the words "Radio Detection and Range". It is used to detect the location, size and speed of objects with radio waves.

Working principle

Electromagnetic signal pulses are sent, and after the energy carried by the radio waves reaches the object, it is reflected back from the object, these reflected signals are called echoes. The direction of echo intensity and return time are very important for radar. In line with these parameters, the properties of the detected object are determined.

It is also necessary for the echo reflected from the electromagnetic signal sent by the radar to be above a certain level. This level is known as the threshold value.

Areas Where Radars Are Used

Radars are used in civil and military fields. In civil use, in the fields of air traffic control and flight management, traffic management systems, ship traffic at sea, navigation and weather radar and search and rescue, security, vehicles speed sensors;

In military use, they are used for surveillance, observation, target classification and ballistic identification, early warning systems, missile defense, air attack warning, guidance systems, positioning in operations, simulation and modeling tasks.

Basically, we can specify the radar types as pulse radars and continuous wave radars. Although pulse radars are the most widely used type of radar, they work according to the basic principle we have compared above, that is, the system logic that determines target information by sending radio waves and using the time between reflection and reflection. They usually have a single antenna for transmitting and receiving. After sending the wave pulses, they wait for it to reflect from the target and return. Waves travel 300 m in 1 microsecond. If the reflection of a wave emanating from the antenna comes after 2 microseconds, we detect that the target is 300 m away.

Continuous wave radars, on the other hand, work according to the Doppler shift principle, although they use two different antennas for sending and receiving, as receiver and transmitter. With this method, it can be difficult to determine the range of a target and to distinguish between two targets.

Synthetic Aperture Radar (SAR)

It is a radar that sends waves from different and more than one point and processes the reflected waves in accordance with the physical structure of the world to obtain the image of the scanned area.

An image obtained from the ASELSAN SAR Radar.

Resolution means a parameter to distinguish two targets that are close to each other. There are two different resolution variants. Azimuth and range resolution. Azimuth is the effect of detecting two targets as a single target when they are equidistant and close to each other with respect to the radar's antenna. On the other hand, when two targets are at the same distance from the radar station, if one of the waves of the two targets arrives before the other, the radar detects it as a single target.

Arthur Radar, this radar with passive phased array antenna can detect the trajectory of a missile with high precision. Its antenna can scan both elevation and azimuth angles. It can detect dozens of targets simultaneously.

GreenPine Radar

This radar has a phased array antenna and its signals are located in the C band in the frequency range of 500 MHz to 1000 MHz. It can scan an average range of 500 km.