Frequency-directivity scanning in laboratory radar imaging

This work concerns an extension of usual radar imaging in which the pictures of the target do not simply exhibit the position of elementary reflectors but also give the behavior of these reflectors when the frequency and the direction of illumination vary. Essentially, the technique consists in describing the target by a generalized image which can be computed from the knowledge of the backscattering function on a large domain in the angle-frequency space. A discussion of the physical relevance of the approach is given and its conclusions are used to derive a practical formulation relying on a special wavelet transform. The implementation of the technique is developed by using the fast Mellin transform. Special features of the method are the use of data in polar format without resampling and the fact that the computation could be easily parallelized.