Broad observation area and high resolution using identifier for synthetic aperture radars

Abstract

To achieve broad observation areas and high resolution, synthetic aperture radars adopt wavelet-transformed observation areas that contain information on position and velocity. The observation area adopts pseudosignals with scattering information about the position and velocity in three dimensions. The wavelet transform (WT) is applied to micromoving targets to obtain a pseudosignal, and each micromoving target is defined by an Identifier (ID) of parameter scale a and parameter shift b. Because the interval of each micromoving target is minimised by the WT, the array of all micromoving targets becomes a continuum that can be represented by straight or curved lines. Every micromoving target can be identified by an ID as long as the micromoving targets do not overlap. Every moving signal in a three-dimensional space can be identified by the abovementioned ID. The results demonstrated that the observation area can be broadened by employing the minimum number of units with micromoving targets. In addition, micromoving targets in the observation area can be obtained at a high resolution (3 cm), and the position of the ID does not change owing to noise. The developments presented can contribute to the fast detection of earthquakes.