Burst Mode Imaging with ENVISAT-1 ASAR Alternating Polarisation Data

ENVISAT-1 ASAR (alternating polarisation) AP burst data segments frequency-time energy in Doppler histories according to the position of target relative to the burst timeline, at the same time, the energy that a scatterer contributes to the received echo ensemble depends on the relative scatterer position following the azimuth antenna pattern, hence the focused image exhibits the radiometric modulation, an effect known as scalloping. This paper investigates the applicability of the band-limited RD algorithm to process ENVISAT-1 ASAR AP burst-mode data, and shows its ability to remove the influence of the azimuth antenna pattern and to preserve phase information. Then the paper illustrates a strategy of filtering the power detected image to suppress the periodic modulation of the impulse response. Finally, the band-limited RD algorithm and the method of filtering in image power domain are verified by processing the ENVISAT-1 ASAR AP mode burst data