A compact ultra wideband (UWB) monopole antenna with dual band-notched characteristics is presented. The antenna consists a square radiating patch with L shaped slots on the radiation patchand a U shaped slot as the feedline. By cutting two C-shaped slots in the ground plane, additional resonance is excited and hence much wider impedance bandwidth can produced, especially at the higher band, wh...

In the present study, we examined the frequency dependence of auditory search performance. Detection thresholds were measured for an 800-Hz target tone in a sequence of distractor tones (informational masking) as a function of frequency separation between the target and the distractor tones. The results showed that the thresholds decreased monotonically with frequency separation increasing. To ...

We discuss theoretically and demonstrate experimentally the robustness of the adiabatic sum frequency conversion method. This technique, borrowed from an analogous scheme of robust population transfer in atomic physics and nuclear magnetic resonance, enables the achievement of nearly full frequency conversion in a sum frequency generation process for a bandwidth up to two orders of magnitude wi...

A common technique to realize wideband microstrip antenna is by introducing slots at an appropriate position inside the patch. In this communication a stacked configurated microstrip patch antenna with slots similar to ISI shape introduced on a square radiating patch with a microstrip line feed is presented. The slots introduced in the radiating patch of the proposed antenna increase the fringi...

A wideband microstrip forward-wave coupledline coupler with high coupling value is presented. Compared with the conventional edge-coupled microstrip forward-wave coupler, this symmetrical structure, consisting periodic shunt stubs between the two coupled-lines, achieves wider operating bandwidth and larger coupling level. To characterize this structure, the equivalent circuit model is establish...

For the purpose of wideband operations, a bow-tie slot antenna fed by a coplanar waveguide (CPW) is investigated. The design was realized using a tapered metal stub introduced in the middle of the bow-tie slot. The modified structure shows wider bandwidth over the conventional bow-tie slot antenna. Parametric study of this new antenna results in a design procedure that helps design this class o...

The study of the strength of correlations in NaxCoO2 is extended to the x=0 end of the phase diagram, where Mott insulating behavior has been widely anticipated. The inclusion of correlation as modeled by the LDA +U approach leads to a Mott transition in the ag subband if U Uc=2.5 eV. Thus, U smaller than Uc is required to model the metallic, nonmagnetic CoO2 compound reported by Tarascon and c...

Hierarchical-ring based multiprocessors are interesting alternatives to the more popular two-dimensional direct networks. They allow for simple router designs and wider communication paths than their direct network counterparts. There are several ways hierarchical-ring networks can be configured for a given number of processors. Feasible topologies range from tall, lean networks to short, wide ...

Underwater acoustic transducers often include a stack of thickness polarized piezoelectric material pieces of alternating polarity interspersed with electrodes and bonded together. The stack is normally much shorter than a quarter wavelength at the fundamental resonance frequency, so that the mechanical behavior of the transducer is not affected by the segmentation. When the transducer bandwidt...

Guglielmo Marconi probably made the first spread spectrum transmission without even realizing it. His primitive spark-gap transmitter used an RF bandwidth that was much wider than the information bandwidth. Little did he know that his experiment would spark a revolution in communications technology. Today, wireless communications plays an integral part in our daily lives. Cellular phones are qu...