Scalar Calibration for Broadband Synthetic Aperture Radar Operating with Amplitude-Only Data

Off-axis holography techniques, which are commonly used to perform phase retrieval from amplitude-only data, require a full-characterization of the reference signal in terms of amplitude and phase. In this letter, it is demonstrated that the recently proposed version of the off-axis holography, working with a broadband synthetic aperture radar, can bypass the need for this calibration. The strategy is based on employing a calibration object to adjust the system. Furthermore, certain properties of the reflectivity calculation are exploited to correct potential misalignment errors. The performance of the approach is demonstrated by reconstructing the profile of several objects at ${K}_{a}$ -band.