Azimuth ambiguity suppression with triple channel receivers — An experiment result using airborne Ku-band synthetic aperture radar

The displaced phase center antenna technique is a promising technique for spaceborne synthetic aperture radar (SAR) to realize high resolution wide swath imaging. This paper presents an experiment to demonstrate the azimuth ambiguity suppression capability of the technique with airborne Ku-band SAR. The experimental data were acquired with triple receiver antennas and combined with coherent processing called as reconstruction algorithm. Prior to applying the coherent processing which enables a recovery of the unambiguous Doppler spectrum, the proposed processing procedure estimates the error due to the receiver channel's imbalance and Doppler center shift and compensates them. The SAR image reconstructed from three receiver channel data shows the significant azimuth ambiguity suppression compared to the image of single receiver channel data.