Multistatic TomoSAR Ambiguity Suppression Method Based on Multiple Subbands

Compared with the traditional tomographic synthetic aperture radar (TomoSAR) system, multistatic TomoSAR can overcome the physical size limitation, realizing high-resolution 3-D imaging via single pass. However, due to the minimum safety distance limitation between flight platforms, the maximum unambiguous imaging range of multistatic SAR is relatively small, which is difficult to meet the mapping needs of urban high-rise. To address this problem, this paper proposes a multistatic TomoSAR ambiguity suppression method based on multiple subbands. This method can effectively achieve ambiguity suppression and 3-D reconstruction of the target without grating lobes. First, a multistatic TomoSAR imaging model is established. Second, we analyze the mechanism of multiple subbands ambiguity suppression. Finally, we utilize the adaptivity of the sparsity Bayesian recovery via iterative minimum (SBRIM) algorithm to the number of targets to realize multistatic TomoSAR 3-D imaging. The effectiveness of the proposed method is validated by simulations.