An Optimization Method for Shadow Profile Retrieval with Forward Scatter Shadow Ratio

This paper proposes an optimization method of using forward scatter shadow ratio (FSSR) to retrieve the shadow profile of a target. It is shown mathematically that the discrete observations of FSSR can be utilized to retrieve the target’s shadow profile, represented by a finite number of rectangular strips. Numerical analysis is conducted on an idealized FSR system and it is found that using two observation lines instead of one improves the accuracy of target shape retrieval and helps eliminate the ambiguity in locating the target. The proposed method demonstrates abilities of retrieving the shadow profile of targets with various sizes and shapes, with good retrieval performance identified under two conditions: moderate distance between the two observation lines and the target center’s projection on the observation plane being in close proximity to one of the observation lines.