How does radar scanning work?
Radar scans work by emitting electromagnetic waves (usually microwaves or radio waves) from a transmitter antenna. These waves travel through the atmosphere until they encounter an object in their path. When they hit an object, some of the waves reflect back to the radar system. The radar receiver’s antenna then captures these reflected waves, called echoes or returns.
By measuring the time it takes for waves to travel toward the object and back (round trip time), radar systems can determine the distance to the object using the speed of light.
To create a scan, the radar system typically rotates its antenna or moves it in a controlled manner to cover a specific area or volume. This movement allows the radar to emit pulses of waves in different directions, collecting echoes from multiple angles. By combining information from these different angles, radar systems can create a detailed image of objects in the scanned area.
This process of emitting pulses, receiving echoes, and analyzing data is repeated continuously to monitor changes in the environment or track moving targets.
How do radars scan?
Radars scan by systematically emitting pulses of electromagnetic waves and receiving their reflections from objects in their field of view. The scanning process involves several key steps:
- Pulse transmission: The radar system emits short pulses of electromagnetic waves (usually microwaves or radio waves) from its transmitter antenna.
These pulses propagate outward into the surrounding space.
- Echo reception: When these pulses encounter objects such as planes, ships, or weather phenomena (like raindrops or clouds), some of the energy is reflected back to the radar.
- Signal reception: The radar receiver antenna captures these reflected signals, called echoes or returns.
The resistance of the return signal depends on factors such as the size, shape and material composition of the reflecting object.
- Processing: The radar system processes the received signals to determine characteristics such as the distance to the object (range), its direction (azimuth and elevation), and sometimes its speed (Doppler effect).
- Scanning mechanism: Radars use different scanning mechanisms depending on their application:
- Mechanical scanning: Some radars mechanically rotate their antenna to scan the radar beam through a specific azimuth or elevation angle.
- Electronic scanning: Others use phased array antennas to electronically steer the radar beam without moving parts, allowing faster scanning and more precise control over the direction of the beam.
- Sector scanning: In some cases, radars can only scan specific sectors or directions of interest rather than a full 360 degree circle.
Overall, radar digitalization is essential for surveillance, navigation, weather monitoring, and various military and civilian applications.
It enables radar systems to detect, track and analyze objects and environmental conditions over short to long ranges with high accuracy and reliability
