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Walter D. Burnside - IEEE Xplore Author Profile

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A novel design was presented for a miniature corrugated ridged horn antenna. The design was manipulated based upon a special application which had stringent design parameters. In this application two such horn antennas were utilized and antenna isolation and bandwidth were key factors in creating a functional system. It was shown that the horn antenna adhered to all of the design constraints inclu...Show More
In this paper, the impact of the structure scattering between the horn and subreflector of a Cassegrain reflector antenna system has been presented. Typical design steps involve (1) feed design that has very good VSWR and (2) use the far field pattern to compute the illumination on the subreflector and subsequently the main reflector to determine the far field pattern of the whole antenna system.Show More
An "EM workbench" is described. It has a modular, code-independent architecture and a common design environment. The technique for integrating new EM codes is demonstrated with a method-of-moments code specialized for circularly symmetric feed horns, and with a new hybrid DFT-MoM (discrete Fourier transform - method of moments) code for finite-boundary planar phased arrays. The use of a common des...Show More
Multilayer R-Card fences have been designed and evaluated for an outdoor range in order to reduce the ground bounce effects. This design not only can reduce the specular reflection by the ground to the receiving area but also reduce the reflection back to the transmit area due to the corner reflector effects. It has been found from the previous and current studies that tapered R-Card fences can ve...Show More
A numerical technique used to calculate scattered fields from feed/subreflector support struts for reflector antenna system has been described in this presentation. Comparison between calculated and measured patterns, with and without the struts, indicates that the technique implemented is valid in predicting scattered fields from struts with arbitrary cross section. The numerical results presente...Show More
Wireless coverage in urban, suburban, and light industrial areas is a challenging problem for cellular network planners. This is mainly due to scattering from buildings and structures but also because area specific demographic features such as parks, streets, and sports arenas require specialized coverage. A contoured beam reflector antenna is a simple and effective solution for this problem, prov...Show More
This paper focuses on the requirements for antenna and/or RCS measurement systems. It is shown that traditional methods are not satisfactory because they do not take into account the impact of errors on critical measurements to be performed in the range. In order for a facility to perform well, the range stray signals are required to be smaller in magnitude for wider angles relative to the desired...Show More
Compact range reflector edge diffraction can be reduced by using an R-card fence. Well-designed R-cards (resistive sheets) placed in front of reflector edges reduce the field variations in the test zone. The keys to successful R-card design are proper choices of both the geometry and resistance profile. In this paper, a two-dimensional (2-D) version of the problem is attacked to show the basic con...Show More
A synthesis technique based on a mechanical finite-element (FEM) surface description of dual-offset reflector (DOSR) surfaces is described. This technique is used to implement a reconfigurable contour beam for a geostationary satellite application. The mechanical finite-element description of the surface takes into account the mechanical properties of the reflector surfaces and the effect of a fin...Show More
The expansion in terrestrial and space communications often requires antennas to be installed in very confined areas on a tower or spacecraft. Since installation and structure variables increasingly dominate the overall communications system performance, an analysis of such structures can be very important. The structures of interest are often in the near field of the antenna, but most antenna des...Show More
This paper describes a standoff, focused-beam, ground-penetrating radar (GPR) for detecting buried antipersonnel (AP) mines. The radar features a 1 to 6 GHz, pulsed stepped-frequency microwave source with hardware range gate, an ultrawide bandwidth feed antenna, and an offset parabolic reflector. A focused-beam, created by feeding the reflector from an offset position, reduces the surface clutter ...Show More
A novel stable beamwidth, ultrawide-bandwidth low-scattering antenna is presented. This antenna is a modified version of the conducting slotline bowtie hybrid (SBH) antenna with resistive sheets (Rcards) introduced into the guiding structure design. Since the resistive sheets can attenuate creeping wave fields, much smaller rolled edges are needed in the Rcard SBH antenna. Moreover, due to the Rca...Show More
The slotted/bow-tie hybrid antenna (SBH) has been developed and widely produced by the Ohio State University-ElectroScience Lab for many years. As an ultra wideband horn, the SBH antenna maintains a very stable pattern with frequency. This makes the SBH very useful for different applications. The purpose of this paper is to investigate how the geometrical parameters of the SBH antenna affect its b...Show More
A mechanical finite element code is incorporated into a diffraction synthesis code to enable direct synthesis of a reconfigurable dual offset reflector antenna. Contour beam in terms of the actuator amplitudes and positions. The code allows realistic modeling of real reflector surfaces using the mechanical properties of the surface material. A description of the code is given and an example of a d...Show More
Compact range measurements with a serrated edge and a blended, rolled edge reflector are compared. This is done by using simulated antenna pattern and backscattered field measurements. The measurement errors caused by stray signals emanating from the edge termination of reflector are discussed. It has been found that different stray signal sources impact on the measurement accuracy from different ...
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A data compression technique to efficiently compress the scattered fields from complex targets is presented. Since at high frequencies the scattered fields from complex radar targets exhibit a highly localized behavior, the data compression technique is based on extracting and then sampling the responses associated with individual scattering mechanisms. The compression technique preserves the angl...Show More
Pyramidal- and wedge-absorber materials are used extensively in anechoic measurement chambers to attenuate stray signals. Typical absorber layouts result in large absorber walls in which the absorber tips and bases are roughly aligned in the same plane. Such a quasi-periodic configuration produces a strong coherent specular reflection which dominates the absorber scattered field. Based on the mult...Show More
The performance trade-off between serrated edge and blended rolled edge compact range reflectors is investigated. The edge diffracted fields which contribute to stray signals in the quiet zone have to be minimized. Consequently, an iterative approach has been developed to design serrated edges such that the edge diffracted rays from the serrations can be kept as far away as possible from the desir...Show More
Ground penetration radar (GPR) requires not only target detection but also identification. Many such targets have simple geometry and their late time impulse responses are dominated by only a few complex natural resonances (CNR). An example is the detection of unexploded ordnance. These CNR's represent an attractive way for target identification. The low SNR, spurious poles and multiple targets pr...Show More
Microstrip antennas have been employed in airborne and spacecraft systems because of their low profile and conformal nature. Recently, they are being used for other commercial applications such as GPS. Most of the antenna design schemes assume that the microstrip elements are mounted on an infinitely large ground plane, therefore, the diffraction from the edges of the ground plane is usually negle...Show More
The UTD corner diffraction solution for a perfectly conducting corner is empirically modified for the case of a dielectric corner. The dielectric may be lossless or lossy, but is assumed to be homogeneous. This modified solution is used to calculate the bistatic scattering from the tip of a dielectric pyramid. Sample calculations display some features of the scattering from a single lossy dielectr...
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A new hybrid method that removes typical discontinuities and singularities of UTD solutions is described and applied to scattering by complex structures. The scattered fields from the structure are first computed on a surface S enclosing it. Then these fields are used to compute an equivalent set of electric and magnetic currents, which are then used to find the scattered fields from the structure...Show More
The presence of stray signals in an antenna measurement range can cause errors in the measured patterns. In order to measure low sidelobe antennas in an antenna range, the stray signals in the range should be very small (at least 8-10 dB below the sidelobe level). It may not be possible to achieve such low level stray signals in a real world antenna range. Thus, alternate methods for reducing thes...Show More