Research output: Chapter in Book/Report/Conference proceeding › Conference paper

**3D scattering by large inhomogeneous 2D objects: Validation of a full-wave 2.5D VIE Solver with mm-wave Gaussian beam and microwave experiments.** / Van Den Bulcke, Sarah; Franchois, Ann; Geffrin, J.m.; Zhang, Lixiao; Stiens, Johan.

Research output: Chapter in Book/Report/Conference proceeding › Conference paper

Van Den Bulcke, S, Franchois, A, Geffrin, JM, Zhang, L & Stiens, J 2008, 3D scattering by large inhomogeneous 2D objects: Validation of a full-wave 2.5D VIE Solver with mm-wave Gaussian beam and microwave experiments. in *Progress in Electromagnetics Research Symposium PIERS.* Finds and Results from the Swedish Cyprus Expedition: A Gender Perspective at the Medelhavsmuseet, Stockholm, Sweden, 21/09/09.

Van Den Bulcke, S., Franchois, A., Geffrin, J. M., Zhang, L., & Stiens, J. (2008). 3D scattering by large inhomogeneous 2D objects: Validation of a full-wave 2.5D VIE Solver with mm-wave Gaussian beam and microwave experiments. In *Progress in Electromagnetics Research Symposium PIERS *

Van Den Bulcke S, Franchois A, Geffrin JM, Zhang L, Stiens J. 3D scattering by large inhomogeneous 2D objects: Validation of a full-wave 2.5D VIE Solver with mm-wave Gaussian beam and microwave experiments. In Progress in Electromagnetics Research Symposium PIERS. 2008

@inproceedings{1fe1a73147e84e188bd9fe99a3d359ad,

title = "3D scattering by large inhomogeneous 2D objects: Validation of a full-wave 2.5D VIE Solver with mm-wave Gaussian beam and microwave experiments",

abstract = "For the development of active millimeter wave imaging systems, e.g. to detect concealed ob- jects on the human body, it is important to be able to simulate some representative scattering con¯gurations. Typically, Gaussian beams are used in active imaging systems. Since these beams only illuminate a spatially limited region, the human body and various objects can be treated as two-dimensional (2D) (in)homogenous cylinders. However, the incident Gaussian beam has a 3D character. Therefore, a 2.5D full-wave Volume Integral Equation (VIE) forward solver is developed: only the cylinder's cross-section is discretized, reducing the number of unknowns strongly, while the incident ¯elds (e.g. oblique plane waves and 3D Gaussian beams) maintain their full 3D character. In this paper, a vectorial Gaussian beam is constructed by using a dipole source in a complex point. This elegant implementation is valid in the near and far ¯eld of the beam. Furthermore, simulation results are compared to measurements to validate the 2.5D numerical scheme. In a ¯rst measure- ment set-up, the scatterer is a long inhomogeneous dielectric cylinder, illuminated by plane waves under di{\circledR}erent elevation angles at microwave frequencies in the range 1 - 18 GHz. Simulations agree well with the experimental results for normally incident plane waves and plane waves with a small elevation angle, for all measured frequencies. For larger elevation angles, the ¯niteness of the cylinder in°uences the results and decreases the agreement. The second measurement set-up consists of a long te°on cylinder, illuminated by a normally incident Gaussian beam at 94 GHz. The measured incident and total ¯eld amplitudes correspond well to the simulated ones. Hence, the 2.5D algorithm is proven to be a valuable simulation tool to study scattering of long inhomogeneous dielectric objects, illuminated by 3D plane waves or 3D Gaussian beams under di{\circledR}erent elevation angles.",

keywords = "active millimeter wave imaging, 3D Scattering, Full-Wave 2.5D VIE Solver",

author = "{Van Den Bulcke}, Sarah and Ann Franchois and J.m. Geffrin and Lixiao Zhang and Johan Stiens",

year = "2008",

month = "7",

day = "2",

language = "English",

isbn = "978-1-934142-05-9",

booktitle = "Progress in Electromagnetics Research Symposium PIERS",

}

TY - GEN

T1 - 3D scattering by large inhomogeneous 2D objects: Validation of a full-wave 2.5D VIE Solver with mm-wave Gaussian beam and microwave experiments

AU - Van Den Bulcke, Sarah

AU - Franchois, Ann

AU - Geffrin, J.m.

AU - Zhang, Lixiao

AU - Stiens, Johan

PY - 2008/7/2

Y1 - 2008/7/2

N2 - For the development of active millimeter wave imaging systems, e.g. to detect concealed ob- jects on the human body, it is important to be able to simulate some representative scattering con¯gurations. Typically, Gaussian beams are used in active imaging systems. Since these beams only illuminate a spatially limited region, the human body and various objects can be treated as two-dimensional (2D) (in)homogenous cylinders. However, the incident Gaussian beam has a 3D character. Therefore, a 2.5D full-wave Volume Integral Equation (VIE) forward solver is developed: only the cylinder's cross-section is discretized, reducing the number of unknowns strongly, while the incident ¯elds (e.g. oblique plane waves and 3D Gaussian beams) maintain their full 3D character. In this paper, a vectorial Gaussian beam is constructed by using a dipole source in a complex point. This elegant implementation is valid in the near and far ¯eld of the beam. Furthermore, simulation results are compared to measurements to validate the 2.5D numerical scheme. In a ¯rst measure- ment set-up, the scatterer is a long inhomogeneous dielectric cylinder, illuminated by plane waves under di®erent elevation angles at microwave frequencies in the range 1 - 18 GHz. Simulations agree well with the experimental results for normally incident plane waves and plane waves with a small elevation angle, for all measured frequencies. For larger elevation angles, the ¯niteness of the cylinder in°uences the results and decreases the agreement. The second measurement set-up consists of a long te°on cylinder, illuminated by a normally incident Gaussian beam at 94 GHz. The measured incident and total ¯eld amplitudes correspond well to the simulated ones. Hence, the 2.5D algorithm is proven to be a valuable simulation tool to study scattering of long inhomogeneous dielectric objects, illuminated by 3D plane waves or 3D Gaussian beams under di®erent elevation angles.

AB - For the development of active millimeter wave imaging systems, e.g. to detect concealed ob- jects on the human body, it is important to be able to simulate some representative scattering con¯gurations. Typically, Gaussian beams are used in active imaging systems. Since these beams only illuminate a spatially limited region, the human body and various objects can be treated as two-dimensional (2D) (in)homogenous cylinders. However, the incident Gaussian beam has a 3D character. Therefore, a 2.5D full-wave Volume Integral Equation (VIE) forward solver is developed: only the cylinder's cross-section is discretized, reducing the number of unknowns strongly, while the incident ¯elds (e.g. oblique plane waves and 3D Gaussian beams) maintain their full 3D character. In this paper, a vectorial Gaussian beam is constructed by using a dipole source in a complex point. This elegant implementation is valid in the near and far ¯eld of the beam. Furthermore, simulation results are compared to measurements to validate the 2.5D numerical scheme. In a ¯rst measure- ment set-up, the scatterer is a long inhomogeneous dielectric cylinder, illuminated by plane waves under di®erent elevation angles at microwave frequencies in the range 1 - 18 GHz. Simulations agree well with the experimental results for normally incident plane waves and plane waves with a small elevation angle, for all measured frequencies. For larger elevation angles, the ¯niteness of the cylinder in°uences the results and decreases the agreement. The second measurement set-up consists of a long te°on cylinder, illuminated by a normally incident Gaussian beam at 94 GHz. The measured incident and total ¯eld amplitudes correspond well to the simulated ones. Hence, the 2.5D algorithm is proven to be a valuable simulation tool to study scattering of long inhomogeneous dielectric objects, illuminated by 3D plane waves or 3D Gaussian beams under di®erent elevation angles.

KW - active millimeter wave imaging

KW - 3D Scattering

KW - Full-Wave 2.5D VIE Solver

M3 - Conference paper

SN - 978-1-934142-05-9

BT - Progress in Electromagnetics Research Symposium PIERS

ER -

ID: 1654556