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PubMed · 15651607

Model-based microwave image reconstruction: simulations and experiments.

Razvan Ciocan·Huabei Jiang
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Abstract

We describe an integrated microwave imaging system that can provide spatial maps of dielectric properties of heterogeneous media with tomographically collected data. The hardware system (800-1200 MHz) was built based on a lock-in amplifier with 16 fixed antennas. The reconstruction algorithm was implemented using a Newton iterative method with combined Marquardt-Tikhonov regularizations. System performance was evaluated using heterogeneous media mimicking human breast tissue. Finite element method coupled with the Bayliss and Turkel radiation boundary conditions were applied to compute the electric field distribution in the heterogeneous media of interest. The results show that inclusions embedded in a 76-diameter background medium can be quantitatively reconstructed from both simulated and experimental data. Quantitative analysis of the microwave images obtained suggests that an inclusion of 14 mm in diameter is the smallest object that can be fully characterized presently using experimental data, while objects as small as 10 mm in diameter can be quantitatively resolved with simulated data.

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AlgorithmsArtificial IntelligenceBreast NeoplasmsComputer GraphicsComputer SimulationHumansImage Interpretation, Computer-AssistedMicrowavesModels, BiologicalNumerical Analysis, Computer-AssistedPhantoms, ImagingReproducibility of ResultsSensitivity and SpecificitySignal Processing, Computer-AssistedSubtraction TechniqueTomographyUser-Computer InterfaceComparative StudyEvaluation StudyJournal ArticleResearch Support, Non-U.S. Gov't

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Razvan Ciocan, Huabei Jiang. 2004. Model-based microwave image reconstruction: simulations and experiments.. https://doi.org/10.1118/1.1812871

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