A note on the predictions of models with modular flavor symmetries

Models with modular flavor symmetries have been thought to be highly predictive. We point out that these predictions are subject to corrections from non–holomorphic terms in the Lagrangean. Specifically, in the models discussed in the literature, the Kähler potential is not fixed by the symmetries, for instance. The most general Kähler potential consistent with the symmetries of the model contains additional terms with additional parameters, which reduce the predictive power of these constructions. We also comment on potential ways of how one may conceivably retain the predictivity

Prototype construction of a compiler for network analysis feasibility study

Feasibility of unified compilers for network analysi

Compact printed ultra-wideband antenna: corrugated monopole augmented with parasitic strips

© 2016 Informa UK Limited, trading as Taylor & Francis Group. A novel compact microstrip line-fed ultra-wideband (UWB) antenna is reported in this paper. The antenna consists of a corrugated half-ellipse monopole and three strips that act as near-field resonant parasitic (NFRP) elements. The entire UWB band (3.1–10.6 GHz) is covered from a very compact size: 19 mm × 10 mm. Two of the NFRP strips are utilized to cover more effectively the lower portion of the UWB frequency range; the third one improves the broadside gain values by 3.28 dB in the upper portion. As a consequence, this compact design maintains a stable radiation performance over the entire UWB band

Experimentally Validated, Planar, Wideband, Electrically Small, Monopole Filtennas Based on Capacitively Loaded Loop Resonators

© 2016 IEEE. Two planar efficient wideband electrically small monopole filtennas are presented. The first one directly evolved from a common planar capacitively loaded loop (CLL)-based filter. This filtenna possesses a flat realized gain response within the operational band and good band-edge selectivity. The second filtenna consists of a driven element augmented with a CLL structure and with slots etched into its ground plane. It expands the fractional impedance bandwidth of the first case from 6.28% up to 7.9%. It too has a gain response that remains flat over its operational bandwidth and even higher band-edge selectivity. Both filtennas are electrically small: ka < 1. The experimental results, which are in good agreement with their simulated values, demonstrate that both filtennas exhibit excellent impedance matching, high radiation efficiency, flat gain response, and steep skirts at both band edges, as well as producing monopole radiation patterns that are uniform and nearly omnidirectional in their H-planes

Bandwidth-enhanced, compact, near-field resonant parasitic filtennas with sharp out-of-band suppression

© 2002-2011 IEEE. The designs, simulations, and measurements of a class of compact, bandwidth-enhanced filtennas are reported. Our design strategy is illustrated by separately designing a monopole and a bandpass filter to operate primarily in their respective fundamental modes. By combining these elements and manipulating the mutual coupling between them, an enhanced impedance bandwidth filtenna is realized. This strategy is applied to augment metamaterial-inspired near-field resonant parasitic antennas with filters. Simulations of these filtenna systems demonstrate that one can maintain stable radiation performance characteristics no matter how one arranges their component configurations, i.e., their relative positions and orientations. A selected filtenna design prototype was fabricated and tested. The good agreement between the simulated and measured results validates these design principles

Particle swarm optimized, 3-d-printed, wideband, compact hemispherical antenna

© 2002-2011 IEEE. A three-dimensional (3-D)-printed, wideband, compact hemispherical-shaped antenna is presented. It consists of a driven strip monopole and several parallel near-field resonant parasitic (NFRP) strips that reside on the surfaces of a hemispherical shell. The monopole strip lies on the interior surface; the NFRP strips lie on the exterior one. This arrangement facilitates the requisite stable near-field capacitive coupling between them over a wide frequency range. The particle swarm optimization algorithm is used to define the lengths and locations of these NFRP strips to achieve its optimized operational bandwidth around 700 MHz given its compact size. The hemispherical shell was 3-D printed with acrylonitrile butadiene styrene resin; the strips were applied to it with silver paste. This prototype was tested. The measured results, in agreement with their simulated values, demonstrate that it achieves a 17.97% -10 dB fractional impedance bandwidth over which stable realized gain values, near 3.5 dBi, are attained. With its low-cost fabrication and attractive performance characteristics, this 3-D printed antenna is suitable for indoor multipath wireless communication systems

Designs of Compact, Planar, Wideband, Monopole Filtennas with Near-Field Resonant Parasitic Elements

© 2018 IEEE. Two planar efficient wideband, electrically small monopole filtennas are presented. The first one directly evolves from a common planar capacitively loaded loop (CLL)-based filter possessing a flat realized gain response within the operational band and good band-edge selectivity. The second filtenna consists of a driven element augmented with a CLL structure and with slots etched into its ground plane. It expands the fractional impedance bandwidth of the first case from 6.28 percent up to 7.9 percent. It also has a gain response that remains flat over its operational bandwidth and even higher band-edge selectivity. Both filtennas are electrically small with ka less than 1. The experimental results, which are in good agreement with their simulated values, demonstrate that both filtennas exhibit excellent impedance matching, high radiation efficiency, flat gain response, and steep skirts at both band edges. Moreover, they produce monopole radiation patterns that are uniform and nearly omnidirectional in their H-planes