Tree-interior radar (TIR) imaging using matching pursuit algorithm and comparison to other TIR focusing techniques

Abstract

The implementation of the matching pursuit algorithm (MPA) to the circular tree-interior imaging scanning arrangement has been introduced. Simulation and measurement experiments have been carried out in aiming to detect and image cavity regions inside tree bodies using the MPA. First, the validity and the success of the MPA has been checked by the help of simulation scenario that was realized in MATLAB environment. Then, the focusing ability and the success of the MPA implementation has been compared to other focusing algorithms; namely sinusoidal template-based focusing algorithm (STBA) and circular back projection algorithm (CBPA) that were developed in our previous studies for imaging the interior of the tree body. After demonstrating the perfect reconstruction of the simulated cavity structure together with the tree-body in the simulated scenario, the implementation of MPA has been applied to the measurement data that were collected in the laboratory. The resultant focused radar images of the measured data have demonstrated that MPA has the ability to focus the tree-interior back-scattered data with sufficiently sharp resolution performance so that the MPA can be successfully utilized for the detection of cavity regions inside tree trunks. The radar images constructed in this study have also shown that the MPA outperforms the previously developed STBA and the CBPA in terms of image quality parameters such as focusing, contrast and resolution.