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Minimum Detectable Velocity, MDV

Minimum Detectable Velocity (MDV) is a parameter for Synthetic Aperture Radar (SAR) with a Ground Moving Target Indication (GMTI) capability, i.e., the ability to detect moving targets on the ground. MDV is the minimum detectable radial velocity of targets moving on the ground.

Ground moving targets can only be detected if their Doppler frequency is significantly different from the Doppler frequency of the fixed target environment. It results from the bandwidth (B) of the frequency spread of the Doppler frequencies of the fixed-target echoes on the ground and thus depends on the wavelength (λ), the velocity (vP) of the platform, and from which elevation angle (EL) the target is viewed.

(1)

  • λ = wavelength of the radar transmitter
  • L = base length of the synthetic aperture
  • vP = velocity of the radar platform
  • EL = elevation angle

If the radial velocity of a target is less than the MDV, then the target is in a so-called blind zone and will not be detected by the radar. These blind zones are masked out by the radar's GMTI algorithms.