# Method of Multi-Angle Transmission Radiowave Tomography of Dielectric Objects
## 3 Method of Inverse Task Solution
Good performance is realized through the use of the fast Fourier transform algorithm. The image of heterogeneities is calculated without multiple iterations. This method is not iterative, but we assume that in the future, this method can be used to obtain the first approximation for iterative methods to reduce computation time, but this is a separate study and requires additional research. **Author Contributions:** Conceptualization, D.S. and K.Z. ; methodology, D.S. ; validation, D.S. ; formal analysis, K.Z. ; investigation, D.S. ; resources, D.S. ; data curation, K.Z. ; writing--original draft preparation, D.S. ; writing--review and editing, K.Z. ; visualization, D.S. ; supervision, K.Z. ; project administration, K.Z. All authors have read and agreed to the published version of the manuscript. **Funding:** This research was funded by Russian Science Foundation, grant number 18-75-10101. The APC was funded by Russian Science Foundation. **Conflicts of Interest:** The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results. ## References

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