Microwave Holography Using Point-Spread Functions Measured With Calibration Objects

Microwave holography requires knowledge of the incident field and the Green tensor of the background medium. In near-field imaging, analytical models of these are inadequate and the use of electromagnetic simulations has been previously proposed. In practice, however, the fidelity of such simulations may also be insufficient. Here, we propose a measurement method for the acquisition of this information, thus eliminating the need to estimate it analytically or numerically. We validate the approach through simulated data acquisitions as well as through experiments. It is shown that this approach characterizes the measurement system more reliably than simulations leading to significant improvement of the image quality.