Performance analysis of a contrast-based ISAR autofocusing algorithm

The ISAR imaging technique is a well consolidated method for target image reconstruction. One of the main critical steps of the technique is motion compensation. This operation consists of removing from the received signal a phase term due to the translational motion of the target. As the target motion is not a priori known, motion parameters are typically estimated from the received data by means of autofocusing techniques. Different techniques are proposed in the literature. Their effectiveness is demonstrated by showing the results obtained by applying the algorithms to real and simulated data, without giving a quantitative analysis of their performance. The goal of this work is to analyze the performance of an image contrast-based ISAR autofocusing technique developed by the authors. The results are provided in terms of the statistics of the focusing parameter estimation errors.