Publications 1993 2017

  • 20 h-Index
  • 73 Conference contribution
  • 73 Article
  • 2 Chapter
2017

Characterization of Y-Bias Ferrite Materials For Tunable Antenna Applications Using A Partially-Filled Rectangular Waveguide

Tang, J., Tayebi, A., Crowgey, B., Rothwell, E., Shanker, B., Kempel, L. & Havrilla, M. Aug 5 2017 (Accepted/In press) In : IEEE Transactions on Antennas and Propagation.

Research output: Research - peer-reviewArticle

rectangular waveguides
ferrites
antennas
Rectangular waveguides
Ferrite
2016
1 Citations

Core/Shell Iron/Oxide Nanoparticles for Improving the Magneto-Dielectric Properties of Polymer Composites

Yang, T. I., Chuang, C. Y., Yang, S. C., Kempel, L. C. & Kofinas, P. Jan 1 2016 In : Advanced Engineering Materials. 18, 1, p. 121-126 6 p.

Research output: Research - peer-reviewArticle

Iron oxides
Dielectric properties
Nanoparticles
Composite materials
Polymers

Radiation properties of a rectangular patch antenna loaded with a magnetoelectric material

Kempel, L., Shanker, B. & Vittoria, C. Oct 25 2016 2016 IEEE Antennas and Propagation Society International Symposium, APSURSI 2016 - Proceedings. Institute of Electrical and Electronics Engineers Inc., p. 1731-1732 2 p. 7696572

Research output: ResearchConference contribution

patch antennas
radiation
Microstrip antennas
Radiation
permeability
2 Citations

Stretchable magneto-dielectric composites based on raspberry-shaped iron oxide nanostructures

Vural, M., Gerber, O., Pichon, B. P., Lemonnier, S., Barraud, E., Kempel, L. C., Begin-Colin, S. & Kofinas, P. Mar 28 2016 In : Journal of Materials Chemistry C. 4, 12, p. 2345-2352 8 p.

Research output: Research - peer-reviewArticle

Nanostructures
Composite materials
ferric oxide
Iron oxides
Fillers
2015
6 Citations

A multilayered metamaterial-inspired miniaturized dynamically tunable antenna

Myers, J. C., Chahal, P., Rothwell, E. & Kempel, L. Apr 1 2015 In : IEEE Transactions on Antennas and Propagation. 63, 4, p. 1546-1553 8 p., 7027210

Research output: Research - peer-reviewArticle

antennas
pixels
Metamaterials
Pixels
Antennas

Distributed linear antenna array pattern performance enhancement

Adrian, A. & Kempel, L. C. Oct 22 2015 2015 IEEE Antennas and Propagation Society International Symposium, APS 2015 - Proceedings. Institute of Electrical and Electronics Engineers Inc., Vol. 2015-October, p. 2497-2498 2 p. 7305637

Research output: ResearchConference contribution

Array processing
Antenna arrays

Longitudinal groove loading of a half-width microstrip leaky-wave antenna

Oladimeji, K., Frasch, J., Rothwell, E. & Kempel, L. Oct 21 2015 2015 USNC-URSI Radio Science Meeting (Joint with AP-S Symposium), USNC-URSI 2015 - Proceedings. Institute of Electrical and Electronics Engineers Inc., p. 40 1 p. 7303324

Research output: ResearchConference contribution

communication system
ability
Antennas
Microstrip antennas
Communication systems
2014
2 Citations

A hybrid vector generalized finite-element method for transient electromagnetic simulations

Tuncer, O., Shanker, B. & Kempel, L. C. Apr 3 2014 In : Electromagnetics. 34, 3-4, p. 286-297 12 p.

Research output: Research - peer-reviewArticle

finite element method
electromagnetism
simulation
Finite element method
Galerkin method
1 Citations
Magnetic materials
Waveguides
Microwaves
magnetic materials
waveguides
3 Citations

Discontinuous galerkin inspired framework for vector generalized finite-element methods

Tuncer, O., Shanker, B. & Kempel, L. C. 2014 In : IEEE Transactions on Antennas and Propagation. 62, 3, p. 1339-1347 9 p., 6689302

Research output: Research - peer-reviewArticle

finite element method
Galerkin methods
Finite element method
Galerkin method
Communication

Gyromagnetic material characterization and error analysis using a partially-filled waveguide technique

Tang, J., Crowgey, B. R., Rothwell, E. J., Shanker, B., Kempel, L. C. & Havrilla, M. Nov 12 2014 2014 USNC-URSI Radio Science Meeting (Joint with AP-S Symposium), USNC-URSI 2014 - Proceedings. Institute of Electrical and Electronics Engineers Inc., p. 9 1 p. 6955391

Research output: ResearchConference contribution

Error analysis
Waveguides
Mechanical testing
Tensors
Antennas
9 Citations

Nanostructured flexible magneto-dielectrics for radio frequency applications

Vural, M., Crowgey, B., Kempel, L. C. & Kofinas, P. Jan 28 2014 In : Journal of Materials Chemistry C. 2, 4, p. 756-763 8 p.

Research output: Research - peer-reviewArticle

Nanoparticles
Citric Acid
Heterojunctions
Composite materials
Saturation magnetization
2013
6 Citations

Characterization of biaxial anisotropic material using a reduced aperture waveguide

Crowgey, B. R., Tuncer, O., Tang, J., Rothwell, E. J., Shanker, B., Kempel, L. C. & Havrilla, M. J. 2013 In : IEEE Transactions on Instrumentation and Measurement. 62, 10, p. 2739-2750 12 p., 6544638

Research output: Research - peer-reviewArticle

apertures
waveguides
Waveguides
reflectance
coefficients

Characterization of gyromagnetic materials using a partially-filled waveguide technique

Tang, J., Crowgey, B. R., Tuncer, O., Rothwell, E. J., Shanker, B., Kempel, L. C. & Havrilla, M. 2013 2013 USNC-URSI Radio Science Meeting (Joint with AP-S Symposium), USNC-URSI 2013 - Proceedings. p. 227 1 p. 6715531

Research output: ResearchConference contribution

Tensors
Waveguides
Permittivity

GMM: A flexible framework for including multiple approximation functions in integral equation solvers

Dault, D., Nair, N. V., Shanker, B. & Kempel, L. C. 2013 2013 International Symposium on Electromagnetic Theory, EMTS 2013 - Proceedings. p. 151-154 4 p. 6565700

Research output: ResearchConference contribution

Method of moments
Integral equations
Requirements engineering
Scattering
20 Citations

Permittivity of dielectric composite materials comprising graphene nanoribbons. the effect of nanostructure

Dimiev, A., Zakhidov, D., Genorio, B., Oladimeji, K., Crowgey, B., Kempel, L., Rothwell, E. J. & Tour, J. M. Aug 14 2013 In : ACS Applied Materials and Interfaces. 5, 15, p. 7567-7573 7 p.

Research output: Research - peer-reviewArticle

Nanoribbons
Graphene
Nanostructures
Permittivity
Composite materials
2012
1 Citations

A discontinuous Galerkin framework for hybridizing VGFEM and FEM

Tuncer, O., Shanker, B. & Kempel, L. C. 2012 IEEE Antennas and Propagation Society, AP-S International Symposium (Digest). 6349013

Research output: ResearchConference contribution

Galerkin methods
Waveguides
Scattering
Finite element method
2 Citations

A flexible framework for the solution to surface scattering problems using integral equations

Dault, D., Nair, N. V., Shanker, B. & Kempel, L. C. 2012 Proceedings of the 2012 International Conference on Electromagnetics in Advanced Applications, ICEAA'12. p. 148-151 4 p. 6328611

Research output: ResearchConference contribution

Surface scattering
Integral equations
Method of moments
Triangulation
Geometry
19 Citations

A through-dielectric ultrawideband (UWB) switched-antenna-array radar imaging system

Charvat, G. L., Kempel, L. C., Rothwell, E. J., Coleman, C. M. & Mokole, E. L. Nov 1 2012 In : IEEE Transactions on Antennas and Propagation. 60, 11, p. 5495-5500 6 p., 6236029

Research output: Research - peer-reviewArticle

Radar imaging
Antenna arrays
Ultra-wideband (UWB)
Imaging systems
Radar
5 Citations
acoustic scattering
method of moments
integral equations
Equations
Generalized Method of Moments

Measurement of anisotropic material properties for antenna applications

Crowgey, B., Tang, J., Tuncer, O., Kempel, L., Rothwell, E. & Shanker, B. 2012 LAPC 2012 - 2012 Loughborough Antennas and Propagation Conference. 6402939

Research output: ResearchConference contribution

Materials properties
Antennas
Scattering parameters
Rectangular waveguides

Radiation of a circularly-polarized microstrip antenna through an uniaxial superstrate: A preliminary study

Ahmed, F., Al-Sulaifanie, B. K. M., Crowgey, B., Rothwell, E., Shanker, B. & Kempel, L. 2012 LAPC 2012 - 2012 Loughborough Antennas and Propagation Conference. 6402970

Research output: ResearchConference contribution

Microstrip antennas
Radiation
Polarization
Antennas
Circular polarization
3 Citations

Tetrahedral-based vector generalized finite element method and its applications

Tuncer, O., Shanker, B. & Kempel, L. C. 2012 In : IEEE Antennas and Wireless Propagation Letters. 11, p. 945-948 4 p., 6269044

Research output: Research - peer-reviewArticle

Finite element method
Polynomials
Antennas
2011
2 Citations

A discretization framework for scalar integral equations using the generalized method of moments and locally smooth surface approximations

Nair, N. V., Shanker, B. & Kempel, L. 2011 IEEE Antennas and Propagation Society, AP-S International Symposium (Digest). p. 3193-3196 4 p. 5997212

Research output: ResearchConference contribution

Method of moments
Integral equations
Acoustics
Scattering
3 Citations

A hybrid discontinuous Galerkin-vector generalized finite element method for electromagnetics

Tuncer, O., Shanker, B. & Kempel, L. C. 2011 IEEE Antennas and Propagation Society, AP-S International Symposium (Digest). p. 2487-2490 4 p. 5997028

Research output: ResearchConference contribution

Galerkin methods
Electromagnetic fields
Polynomials
Finite element method
41 Citations

Controlled synthesis of core-shell iron-silica nanoparticles and their magneto-dielectric properties in polymer composites

Yang, T. I., Brown, R. N. C., Kempel, L. C. & Kofinas, P. Mar 11 2011 In : Nanotechnology. 22, 10, 105601

Research output: Research - peer-reviewArticle

Silicon Dioxide
Dielectric properties
Polymers
Iron
Nanoparticles
4 Citations

Design study of electronically steerable half-width microstrip leaky wave antennas

Hejase, J. A., Myers, J., Kempel, L. & Chahal, P. 2011 Proceedings - Electronic Components and Technology Conference. p. 1348-1353 6 p. 5898687

Research output: ResearchConference contribution

Antennas
Scanning
Varactors
Metallizing
Diodes
1 Citations

Development of time domain vector generalized finite element method

Tuncer, O., Shanker, B. & Kempel, L. C. 2011 IEEE Antennas and Propagation Society, AP-S International Symposium (Digest). p. 2980-2982 3 p. 5997155

Research output: ResearchConference contribution

Finite element method
Physics
Polynomials
Boundary conditions

Effect of curvature on the performance of a cylindrically-conformal cavity-backed E-patch antenna

Gardner, C. M., Rothwell, E. J., Kempel, L. C., Hejase, J. A., Ouedraogo, R. O. & Schneider, S. W. 2011 In : Applied Computational Electromagnetics Society Journal. 26, 11, p. 930-936 7 p.

Research output: Research - peer-reviewArticle

patch antennas
antennas
curvature
cavities
Microstrip antennas
2 Citations

Generalized method of moments: A flexible discretization scheme for integral equations using locally smooth surface approximations

Nair, N. V., Shanker, B. & Kempel, L. 2011 2011 IEEE International Conference on Microwaves, Communications, Antennas and Electronic Systems, COMCAS 2011. 6105955

Research output: ResearchConference contribution

Method of moments
Integral equations
Scattering
44 Citations

Low-loss, high-permittivity composites made from graphene nanoribbons

Dimiev, A., Lu, W., Zeller, K., Crowgey, B., Kempel, L. C. & Tour, J. M. Dec 28 2011 In : ACS Applied Materials and Interfaces. 3, 12, p. 4657-4661 5 p.

Research output: Research - peer-reviewArticle

Nanoribbons
Graphene
Permittivity
Composite materials
Carbon Nanotubes

Theoretical analysis of a varactor-loaded half-width leaky-wave antenna

Kempel, L., Rothwell, E., Shanker, B. & Chahal, P. 2011 2011 30th URSI General Assembly and Scientific Symposium, URSIGASS 2011. 6050351

Research output: ResearchConference contribution

Varactors
Antennas
Fires
Antenna phased arrays
Bandwidth

Vector generalized finite element method on tetrahedral meshes and applications of its features in electromagnetic simulations

Tuncer, O., Sahin, F. O., Shanker, B. & Kempel, L. C. 2011 IEEE Antennas and Propagation Society, AP-S International Symposium (Digest). p. 2465-2467 3 p. 5997022

Research output: ResearchConference contribution

Finite element method
Polynomials
Demonstrations
Physics
2010
4 Citations

Accelerated Cartesian expansion (ACE) based framework for the rapid evaluation of diffusion, lossy wave, and Klein-Gordon potentials

Vikram, M., Baczewski, A., Shanker, B. & Kempel, L. Dec 10 2010 In : Journal of Computational Physics. 229, 24, p. 9119-9134 16 p.

Research output: Research - peer-reviewArticle

convolution integrals
expansion
evaluation
Convolution
costs

A generalized basis function framework for integral and differential equations in electromagnetics

Tuncer, O., Nair, N. V., Shanker, B. & Kempel, L. C. 2010 2010 Loughborough Antennas and Propagation Conference, LAPC 2010. p. 9-12 4 p. 5666813

Research output: ResearchConference contribution

Integral equations
Differential equations
5 Citations

A hybrid finite element- Vector generalized finite element method for electromagnetics

Tuncer, O., Shanker, B. & Kempel, L. C. 2010 2010 IEEE International Symposium on Antennas and Propagation and CNC-USNC/URSI Radio Science Meeting - Leading the Wave, AP-S/URSI 2010. 5561926

Research output: ResearchConference contribution

Finite element method
Brick
30 Citations

An ultrawideband (UWB) switched-antenna-array radar imaging system

Charvat, G. L., Kempel, L. C., Rothwell, E. J., Coleman, C. M. & Mokole, E. L. 2010 IEEE International Symposium on Phased Array Systems and Technology. p. 543-550 8 p. 5613313

Research output: ResearchConference contribution

Radar imaging
Radar systems
Antenna arrays
Ultra-wideband (UWB)
Imaging systems
47 Citations

A through-dielectric radar imaging system

Charvat, G. L., Kempel, L. C., Rothwell, E. J., Coleman, C. M. & Mokole, E. L. Aug 2010 In : IEEE Transactions on Antennas and Propagation. 58, 8, p. 2594-2603 10 p., 5466037

Research output: Research - peer-reviewArticle

Radar imaging
Imaging systems
Imaging techniques
Air
imaging radar
22 Citations

Beam steering of a half-width microstrip leaky-wave antenna using edge loading

Archbold, M., Rothwell, E. J., Kempel, L. C. & Schneider, S. W. 2010 In : IEEE Antennas and Wireless Propagation Letters. 9, p. 203-206 4 p., 5430969

Research output: Research - peer-reviewArticle

Antennas
Capacitors
Capacitance
28 Citations

Comparison of uwb short-pulse and stepped-frequency radar systems for imaging through barriers

Crowgey, B. R., Rothwell, E. J., Kempel, L. C. & Mokole, E. L. 2010 In : Progress in Electromagnetics Research. 110, p. 403-419 17 p.

Research output: Research - peer-reviewArticle

radar
pulses
Radar systems
Radar
Imaging techniques
14 Citations

Further development of vector generalized finite element method and its hybridization with boundary integrals

Tuncer, O., Lu, C., Nair, N. V., Shanker, B. & Kempel, L. C. Mar 2010 In : IEEE Transactions on Antennas and Propagation. 58, 3, p. 887-899 13 p., 5372011

Research output: Research - peer-reviewArticle

finite element method
Finite element method
Helmholtz equations
flexibility
inhomogeneity
20 Citations

Surfactant-modified nickel zinc iron oxide/polymer nanocomposites for radio frequency applications

Yang, T. I., Brown, R. N. C., Kempel, L. C. & Kofinas, P. Oct 2010 In : Journal of Nanoparticle Research. 12, 8, p. 2967-2978 12 p.

Research output: Research - peer-reviewArticle

iron oxides
zinc oxides
radio frequencies
nanocomposites
surfactants

VGFEM with perfectly matched layers

Tuncer, O., Shanker, B. & Kempel, L. C. 2010 2010 IEEE International Symposium on Antennas and Propagation and CNC-USNC/URSI Radio Science Meeting - Leading the Wave, AP-S/URSI 2010. 5561882

Research output: ResearchConference contribution

Anisotropic media
Polynomials
2009

A trough leaky-wave antenna

Jaramillo-Henao, C. A., Kempel, L. C. & Schneider, S. 2009 IEEE Antennas and Propagation Society, AP-S International Symposium (Digest). 5171768

Research output: ResearchConference contribution

4 Citations

A vector generalized finite element-boundary integral formulation for scattering from cavity-backed apertures

Tuncer, O., Shanker, B. & Kempel, L. C. 2009 IEEE Antennas and Propagation Society, AP-S International Symposium (Digest). 5171717

Research output: ResearchConference contribution

5 Citations

Broadband microstrip leaky wave antenna with inhomogeneous materials

Jiang, H., Penno, R., Pasala, K. M., Kempel, L. & Schneider, S. 2009 In : IEEE Transactions on Antennas and Propagation. 57, 5, p. 1557-1561 5 p.

Research output: Research - peer-reviewArticle

finite element method
antennas
broadband
propagation
Microstrip lines
4 Citations
Polymers
Permittivity
Microwaves
Finite element method
Kinetics
1 Citations

Development of vector basis functions in vector generalized finite element method for inhomogeneous domains

Tuncer, O., Shanker, B. & Kempel, L. C. 2009 IEEE Antennas and Propagation Society, AP-S International Symposium (Digest). 5171545

Research output: ResearchConference contribution

Dielectric relaxation of curing DGEBA/mPDA system at 2.45 GHz

Zobg, L., Hawley, M. C., Sun, R. & Kempel, L. C. May 2009 In : Journal of Thermoplastic Composite Materials. 22, 3, p. 249-257 9 p.

Research output: Research - peer-reviewArticle

Dielectric relaxation
Curing
Temperature
2,2-bis(4-glycidyloxyphenyl)propane
curing
3 Citations

Finite element analysis of conformal antennas

Gardner, C., Jarmillo-Heano, C. & Kempel, L. C. 2009 Proceedings of the 2009 International Conference on Electromagnetics in Advanced Applications, ICEAA '09. p. 844-847 4 p. 5297346

Research output: ResearchConference contribution

Antennas
Bandwidth
Finite element method
Structural loads
Radiators