Terminology » Types of Radar : Key differences with 5-10 examples

Types of Radar : Key differences with 5-10 examples

radar frequency waveform prf application

Radar is the short form of “Radio Detection And Ranging”. It is a powerful active sensing technology that transmits electromagnetic (EM) waves and analyzes the echoes to detect, locate, track and characterize objects at varying distances. It operates primarily in the microwave spectrum (hundreds of MHz to tens of GHz). This page delves into the classification of radar systems, exploring different types based on frequency, waveform, Pulse Repetition Frequency (PRF), and their specific applications.

Radar Classification Radar Classification

Frequency Based Radar Types

Radars are often classified by the frequency bands they utilize. Here are some common frequency-based radar types:

  • HF Band Radars
  • VHF and UHF band radars
  • L-Band Radars
  • S-Band Radars
  • C-Band Radars
  • X-Band Radars
  • Ku, K, Ka Band Radars
  • Infrared, Visible light band radars

Waveform Based Radar Classification

Another method of classifying radar is based on the type of waveform they transmit:

  • Unmodulated CW radar (Continuous Wave)
  • Modulated CW radar
  • Gated CW pulsed radar
  • Complex waveform pulsed radars

PRF Based Radar Types - LPRF Radar and HPRF Radar

Radar systems can also be classified based on their Pulse Repetition Frequency (PRF):

  • LPRF Radar: LPRF stands for Low Pulse Repetition Frequency Radar. It’s particularly useful for determining the range to a target.

  • HPRF Radar: HPRF stands for High Pulse Repetition Frequency Radar. Also known as pulse Doppler radar, it excels at measuring Doppler shift, which allows for velocity determination. However, HPRF radars are generally not used for range measurements.

Application Based Radar Classification

Finally, radar systems are often classified based on their specific applications:

  1. Search radars (surface, air) : Search radars continuously sweep large areas—either above (air search) or across the earth’s surface (surface search)—to detect and localize targets such as aircraft, ships, or vehicles. They emit short pulses and scan 360°, providing initial detection and range information, often with Doppler filtering to distinguish moving targets
  2. Warning radars (e.g., weather forecast radars) : Warning radars encompass systems like weather and storm detection radars. They identify meteorological threats (storms, hail, wind shear) using specialized frequencies and polarizations. Doppler radar measures motion within weather systems, aiding timely alerts
  3. Spacecraft detection radars : These radars operate from ground or space to detect, track, and characterize spacecraft or space debris. They support navigation, docking (e.g., rendezvous), and remote sensing missions such as altimetry and mapping
  4. Fire control radars : Designed for precision tracking of a designated target, fire control radars focus very narrow beams to deliver range, velocity, and angular data directly to weapon systems. They’re essential for missile lock-on and accurate targeting, often integrated with search radars for broader coverage
  5. Ground mapping radars : These radars, typically airborne or spaceborne, produce detailed topographic maps, often utilizing SAR techniques. They scan terrain and produce imagery for geological surveys, environment monitoring, and navigation.
  6. SAR (Synthetic Aperture Radar) : SAR is a high-resolution form of ground or terrain-mapping radar. By using the motion of the radar platform, it synthesizes a large antenna aperture from multiple pulses, generating detailed 2D/3D imagery regardless of weather or daylight
  7. Air to Surface radars : These airborne radars scan the earth’s surface from aircraft or helicopters to detect maritime vessels, terrain features, or ground targets. Ship-based variants are sometimes specifically referred to as ASV (air-to-surface vessel) radar
  8. Sea surface radar : Mounted on ships or coastal stations, these radars are tailored to detect objects on the water. They maximize detection by exploiting sea-reflected signals, while mitigating sea-clutter to reliably identify vessels and surface obstacles
  9. Ground moving target search radars : Also known as GMTI radars, they scan terrain to detect and locate moving ground targets (e.g., vehicles) using Doppler processing to distinguish them from stationary clutter
  10. Tracking radar : Tracking radars lock onto a previously detected target to continually measure its position and velocity. They typically feature narrower beams and faster update rates than search radars, feeding data into fire control or surveillance systems
  11. Range radar : Also known as ranging or distance-measurement radar, this system’s primary function is to determine the precise distance to a target using pulse timing. This core functionality underlies many radar applications, from navigation to altitude measurement.
  12. Velocity search radar : This type of radar focuses on detecting objects based on Doppler velocity shifts rather than range. High-PRF (pulse repetition frequency) Doppler radars excel at isolating fast-moving targets and determining their speed accurately

Conclusion: Throughout this overview, we have explored radar’s many forms; each optimized for distinct roles like detecting aircraft, guiding missiles, mapping terrain, revealing weather patterns or spotting concealed threats. In a world increasingly reliant on situational awareness, radar remains an indispensable lens through which we observe, understand and navigate the unseen.