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A new diffraction coefficient, obtained by modifying the Maliuzhinets' diffraction coefficient, has been proposed here in this article for a double‐layered dielectric wedge which can be considered as an approximated version of a snow or vegetation‐covered dielectric wedge in a practical propagation channel modeling scenario. An experiment was conducted with an artificially created double‐layered wedge for validating the response from the proposed coefficient in a real‐life scenario. The same environment was modeled and simulated using gprMax simulator, which further verified the experimental result and the effectiveness of the newly developed coefficient. [ABSTRACT FROM AUTHOR]

Permittivity of the dielectric objects is calculated using the scattered fields from objects and the incident fields in the investigation domain. In practical applications, calculation of incident fields over closely placed discrete points is a challenging task. In this study, a simple method to calculate incident fields using equivalent sources is proposed. These equivalent sources are modelled from the measured incident fields around the dielectric objects. From these sources, permittivity of the dielectric objects is calculated on experimental data set by employing contrast source inversion technique. Further, the accuracy of the proposed method is studied on synthetic data by approximating the pyramidal horn antenna fields with line and equivalent sources. [ABSTRACT FROM AUTHOR]

ABSTRACT Low-ringing and reduced-cost pulse generators for ultrawideband applications using step recovery diode (SRD) have been reported in this article. The circuits generate Gaussian pulses of 170 ps pulse width and a minimal ringing of −22 dB and monocycles of 401 ps duration and high fractional bandwidth of 162%. Cost-reduction is mainly attributed to the resistive attenuator and single SRD used. Negligible change in circuits' performance was witnessed for repetition rate from 1 to 100 MHz which makes it apt for low to medium range ground penetrating radar applications. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:2289-2294, 2014 [ABSTRACT FROM AUTHOR]

An accurate deterministic model for propagation through buildings is presented.The proposed model gives significant improvement over earlier predicted results. The application of the proposed model is considered for a single building scenario and urban microcellular scenario to demonstrate its accuracy. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26152 [ABSTRACT FROM AUTHOR]

A novel three-dimensional dyadic diffraction coefficient is presented.The proposed coefficient shows significant improvement when compared with published measurement. Further, three-dimensional rooftop scenario is considered and measurement of the electric field in the vicinity of the building is carried out. The measurement result, thus obtained, is compared with predictions using proposed coefficient. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 2132–2136, 2010; Published online in Wiley InterScience (www.interscience. wiley.com). DOI 10.1002/mop.25402 [ABSTRACT FROM AUTHOR]

A design of a miniaturized rat-race coupler with higher-order harmonic suppression is presented in this article. The slow wave effect and stopband produced by a shunt open-stub is utilized to miniaturize the occupying area and suppress higher order harmonics, respectively. Design guidelines are obtained using a transmission line model. A prototype coupler has been fabricated in microstrip line to validate the theoretical predictions. The fabricated coupler occupies 18.4% area of that of a conventional coupler. At the same time, the second to tenth harmonics are suppressed by at least 15 dB. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2812–2814, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23840 [ABSTRACT FROM AUTHOR]

In this article, a compact microstrip coupled-line configuration has been presented to design a wideband bandstop filter with three transmission zeros. These transmission zeros are utilized to obtain sharp rejection characteristics. A loss-less transmission line model is used to obtain the filter design parameters. To validate the theoretical prediction, a single section sharp-rejecting, compact, bandstop filter having a 20-dB rejection bandwidth of ∼100% at 1.5 GHz has been fabricated. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2955–2957, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23819 [ABSTRACT FROM AUTHOR]

In this article, a new configuration has been proposed for miniaturization of a branch-line 90° hybrid coupler. The present coupler is obtained by replacing the low impedance series arms of a conventional coupler by their equivalent parallel high impedance lines. This arrangement facilitates meandering, used to realize a compact geometry. The main advantage of the proposed coupler is that it has approximately the same bandwidth as that of a conventional one. A prototype coupler area is 45.3% of that of a conventional branch-line coupler. The design is validated by full-wave electromagnetic simulation and measurement. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1135–1137, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23320 [ABSTRACT FROM AUTHOR]