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Jeffrey Massman - IEEE Xplore Author Profile

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We previously reported a 3D printed ultra-wide band (UWB) Balanced Antipodal Vivaldi Array (BAVA) with 104 linearly polarized antennas on a hemisphere. In this work, we explore how this concept can be applied to a tactically sized array conformal to a relevant platform. Preliminary measurements of a 732 linearly polarized prototype portray element level gain and impedance consistent with an infini...Show More
This paper introduces an ultrawideband wire-grid polarizer measurement standard for focus beam system cross-polarization calibration. The low-cost design enables polarimetric calibration techniques of precision non-destructive material measurements. Principles from wire-grid polarizers and A-sandwich radomes are combined to develop a highly planar standard. An infinite array simulation is included...Show More
This paper extends the time-domain gated response isolation scheme for full polarimetric calibration with a modified Thru-Reflect-Match procedure for network analyzer self-calibration where precise knowledge of the metrology standards is not required. Cross-polarization contributions from the measurement setup are neglected to simplify the procedure. A simulated cascade analysis is included to dem...Show More
Generalized closed form expressions of the Fresnel coefficients for an arbitrarily incident plane wave upon a simple to biaxial media interface is introduced. The analysis enforces boundary conditions through eigenwave expansions of both the simple media and anisotropic permittivity and permeability biaxial media. This generalized eigenwave approach results in explicit formulations accounting for ...Show More
An analysis to determine the explicit eigenwave solutions for electric and magnetic field components of anisotropic permittivity and permeability biaxial media for any plane wave angle of incidence is introduced. Forward and reverse propagating eigenvalues are identified. Then, the eigenvector is solved to define the electric field polarization before determining the electric and magnetic field ei...Show More
We report the first low-profile array on a doubly curved surface that supports wide angle electronic scanning and ultrawide bandwidth (7:1 ratio). The array elements are based on the balanced antipodal Vivaldi antenna (BAVA). The antennas are optimized for a good impedance match in an infinite planar array environment and are then deformed to fit along the surface of a hemisphere. The array is com...Show More
We report the first ultra-wide band (UWB) arrays on a doubly curved surface for wide angle electronic scanning. Two different prototypes are developed employing Vivaldi antennas and balanced antipodal Vivaldi antennas (BAVAs) distributed over the surface of a hemisphere. The arrays employ 52 dual-polarized elements. Unit cell simulations demonstrate a good impedance match from 2–12 GHz, and finite...Show More
Dropped-channel polarimetric synthetic aperture radar (PolSAR) compressed sensing (CS) [1], [2] recovers an unmeasured polarimetric channel by utilizing antenna crosstalk and CS techniques. A sufficient amount of crosstalk is required for successful recovery; however, dual-polarized antennas are typically designed to have very good channel isolation. A new antenna is needed that can provide high c...Show More
Novel metamaterial and metasurface realizations provide unique control of the wave dispersion but present many challenges for accurate constitutive parameter extraction. Practical material measurement approaches for characterizing complex materials, such as biaxial anisotropic and gyrotropic media, rely on either waveguide or focus beam techniques with trade-offs in sample size and bandwidth. Mult...Show More
A generalized analysis to determine the Cartesian electric and magnetic field components of anisotropic biaxial media based on kDB formalism and coordinate system is introduced. The approach solves for each characteristic eigenwave within kDB system before transforming the fields back to Cartesian coordinates. This formulation accounts for arbitrary plane wave propagation angles in biaxial media a...Show More
We report a conformal ultra-wide band (UWB) array on a doubly curved surface for wide angle electronic scanning. We use a quadrilateral mesh as the basis for systematically arraying UWB radiators on arbitrary surfaces. A 52 element, dual-polarized Vivaldi array prototype on a 181 mm diameter hemisphere is developed. The antennas and connectors are metal 3D printed. Measured realized gain is within...Show More
A methodology to account for rotational alignment errors in the constitutive parameter extraction of biaxial media in focused beam measurement systems is introduced. The electric and magnetic field modal expansion for both excitation polarizations is developed within the principal crystal coordinate axis before subsequent boundary condition enforcement. The theoretical scattering parameters are th...Show More
We report the first conformal ultrawideband (UWB) array on a doubly curved surface for wide-angle electronic scanning. We use a quadrilateral mesh as the basis for systematically arraying UWB radiators on arbitrary surfaces. A prototype consisting of a 52-element, dual-polarized Vivaldi array arranged over a 181 mm diameter hemisphere is developed. The antennas and SMP connectors are 3-D printed o...Show More
We report the first Vivaldi arrays monolithically fabricated exclusively using commercial, low-cost, 3-D metal printing (direct metal laser sintering [DMLS]). Furthermore, we developed one of the first dual-polarized Vivaldi arrays on a triangular lattice, and compare it to a square lattice array. The triangular lattice is attractive because it has a 15.5% larger cell size compared to the square l...Show More
This paper introduces a modular, end-fire, dual-polarized ultra-wideband scalable array (MEDUSA) realized exclusively with titanium direct metal laser sintering (DMLS) to achieve a connector-less phased array antenna module. The radiator is based on a variation of conventional tapered slot antennas (i.e. Vivaldi) to achieve an all metal fully-monolithic element consisting of RF coaxial interface, ...Show More
This paper introduces a modular, end-fire, dual- polarized ultra-wideband scalable array (MEDUSA) realized with stereolithography (SLA) to achieve a novel connector-less phased array radiating element. The radiator is based on a variation of conventional tapered slot antennas (i.e. Vivaldi) where a new integrated balun approach is described which leverages the flexibility provided by additive manu...Show More
A Neural-Network-biased Genetic Algorithm is employed to design all dielectric waveguide with periodic structures with preferential band-pass frequencies. Preliminary results indicate that an optimum periodic structure design exist for target frequency transmission and highlights the need for robust optimization scheme such as the one described here.Show More
The ability to control the bistatic scattering characteristics from cylindrical objects using a tapered cylindrical impedance sheet is presented. It is shown that with the capability to readily control both the real and imaginary components of a percolated lossy film's effective impedance, specific impedance distributions can be obtained to effectively introduce and direct the overall nulls in the...Show More
This paper introduces a reduced aperture flange waveguide technique capable of simultaneously measuring both reflection and transmission coefficients in order to characterize the tapered sheet impedance of a film in a nondestructive manner. This specialized technique employs a stepped flange waveguide and modal analysis approach in order to approximately treat the tapered film as a piecewise-homog...Show More
An arbitrary VHF antenna array was considered for the comparison of two methods of analysis. The first method was based on a Fourier transform decomposition of the far-field radiation integral written in Matlab. In this approach the current on the antenna array is taken to be comprised of simplified functions. The current has three rectilinear components with each component been a product of three...Show More
The ability to manipulate a complex impedance sheet about a cylinder of arbitrary diameter to control the overall scattering characteristics at particular angles for shielding or scattering applications is presented. It is shown that with the capability to readily control both the real and imaginary components of a percolated lossy film's effective impedance, specific impedance distributions can b...Show More