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High Frequency Beam Diffraction By a Dihedral Corner Reflector
Journal of Electromagnetic Waves and Applications, 1998Two dimensional beam diffraction by a 90° -dihedral corner reflector with sides of finite length is analyzed. First the solution for an isotropic electric line source parallel to the corner and edges is obtained for high frequencies by the uniform geometrical theory of diffraction with shadow and reflection boundary positions identified. By introducing
M.K. Mansour, G.A. Suedan, E.V. Jull
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Relation of corner frequency to fault dimensions
Journal of Geophysical Research, 1972The spectrum of the far-field displacement radiation from a conventional fault model has been calculated for comparison with the spectrum calculated from the recent Brune model. The spectrums are generally similar, but some of the details are attributed to different effects in the two models.
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Moments, corner frequencies, and the free surface
Journal of Geophysical Research: Solid Earth, 1978Theoretical amplitude and phase spectra for P and SH body waves are computed for dislocation sources imbedded in an elastic half space to determine the effect of neglecting the free surface in earthquake spectral studies. Depending on source orientation, depth, and time function, errors in moment and corner frequency determinations may be arbitrarily ...
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Radiation characteristics of corner reflector antenna employing frequency selective surface
2016 URSI Asia-Pacific Radio Science Conference (URSI AP-RASC), 2016This paper investigates the half-power-beam-width (HPBW) and front-to-back ratio (FB) characteristics of a corner reflector antenna employing frequency selective surface (FSS). The adjustable HPBW range is clarified by changing the corner angle of the reflector. The influence of the FSS element arrangement on the FB characteristics is also investigated.
Yusuke Tanizawa +3 more
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Reconfigurable Corner Reflector Using PIN-Diode-Switched Frequency Selective Surfaces
2020 IEEE International Symposium on Antennas and Propagation and North American Radio Science Meeting, 2020This paper presents the development of a reconfigurable corner reflector that uses a PIN-diode-switched frequency selective surfaces (FSS). A reflector aperture angle of 45° is prototyped for application at 4 GHz, and its pattern characteristics are altered by on-off state biasing of the PIN diodes.
Deisy Formiga Mamedes +2 more
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Bulletin of the Seismological Society of America, 2020
ABSTRACTOver recent years, a greater importance has been attached to low-magnitude events, with increasing use of the subsurface for industrial activities such as hydraulic fracturing and enhanced geothermal schemes. Magnitude distributions and earthquake source properties are critical inputs when managing the associated seismic risk of these ...
Butcher, Antony C +3 more
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ABSTRACTOver recent years, a greater importance has been attached to low-magnitude events, with increasing use of the subsurface for industrial activities such as hydraulic fracturing and enhanced geothermal schemes. Magnitude distributions and earthquake source properties are critical inputs when managing the associated seismic risk of these ...
Butcher, Antony C +3 more
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A rounded corner triangular patch antenna for dual‐frequency application
Microwave and Optical Technology Letters, 2013ABSTRACTA single layer of equilateral triangular patch antenna is achieved, which operates at 870 MHz and 2.45 GHz suitable for UHF and microwave radio frequency identification application. By shaping the corners of triangular patch, the antenna excites the radiation modes of TM10 and TM21 and suppresses the unwanted TM20 mode to give boresight of ...
Jun Jiat Tiang +3 more
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Implementation of a corner reflector antenna using frequency selective surfaces
2017 IEEE-APS Topical Conference on Antennas and Propagation in Wireless Communications (APWC), 2017In this paper is presented the implementation of a corner reflector antenna where the reflective metal plates are replaced by frequency selective surfaces, FSS, based on the four-arm star geometry. The projected antenna an aperture angle of 60° and operation at 4.0 GHz. The design steps are described and numerical and experiments. For the region within
Nieremberg J. P. de Lyra Ramos +4 more
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Low-frequency topological edge and corner states in metamaterial sandwich plates
Applied AcousticsHanqing Zhang +3 more
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The corner frequencies of the ECG amplifier for heart rate variability analysis
Physiological Measurement, 2004Heart rate variability (HRV) analysis is considered a popular method both in clinical and research fields. However, several ignored technical artifacts may falsify its measurements. The current study investigates the effects of corner frequencies of the ECG amplifier on the precision of RR-interval detection.
Laszlo, Hejjel, Lorand, Kellenyi
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