A ML thinned array SAR interferometric sensor for high accuracy absolute phase retrieval

The paper shows that the recently proposed three-element interferometric technique does not increase the phase ambiguity range in a deterministic manner. Namely there is still a probability that catastrophic phase errors of multiples of 2 pi are present, depending on the signal-to-noise power ratio, the number of looks and the extension of the required ambiguity range. After showing that a full array with the same unambiguous range magnification is much more robust, a thinned array interferometer is proposed. This is shown to have good performance as phase unwrapping and error standard deviation and sensibly reduced costs.