Modern radar works on the principle of transmitting electromagnetic waves, usually in the microwave range, and detecting reflections (echoes) of these waves from objects in the environment. Radar systems consist of a transmitter that emits pulses of electromagnetic radiation, an antenna to transmit these pulses into space, and a receiver to detect returning echoes from targets. The radar system calculates the distance to the target based on the time it takes for the transmitted pulse to return (time of flight), and it determines the direction and speed of the target by analyzing the Doppler shift of the reflected signals. Advanced radar systems also use signal processing techniques and algorithms to filter noise, improve target detection, and improve resolution.
Radar technology remains indispensable in various applications in the modern world. One of the main uses of radar today is in aviation for air traffic control (ATC) and weather monitoring. Air traffic control radar systems track aircraft position, altitude and speed in real time, ensuring safe separation and efficient routing. Weather radar systems monitor precipitation, severe storms and wind patterns, providing vital information to meteorologists and helping to issue timely weather alerts and forecasts. Radar is also widely used in military applications for surveillance, reconnaissance, missile guidance, and defense against air and sea threats.
The frequency of modern radar systems varies depending on the specific application and operational requirements. Radar frequencies generally range from very high frequencies (VHF) to extremely high frequencies (EHF), corresponding to wavelengths of several meters to millimeters. For example, air traffic control radars often operate in the L-band (1-2 GHz) or S-band (2-4 GHz), while weather radars may operate in the C-band (4-8 GHz) or X-band (8-12 GHz). Military radars can use higher frequencies in the X-band or Ku-band (12-18 GHz) for improved resolution and target detection capabilities. The choice of frequency affects radar performance, including range, resolution and sensitivity to weather and environmental conditions, ensuring optimal functionality for specific operational needs.