The present paper describes a capacitive feed (C-feed) for small, low-profile linear antennas. A meander line, which is the radiating element, in such antennas with a metallic back conductor electromagnetically couples a metallic feed plate placed between the meander line and the back metal (ground). This antenna has a very small leakage current on the outer surface of the coaxial cable and can...

This paper presents a method for measuring signal backscattering from an RFID tag and calculating tag radar cross-section (RCS), which depends on the chip input impedance. We present a derivation of a theoretical formula for RFID tag radar cross-section and an experimental RCS measurement method using a network analyzer connected to an antenna in an anechoic chamber where the tag is also locate...

An end-launched adapter combining a coaxial loop within a rectangular waveguide has been analyzed and designed. The accurate electromagnetic modeling of input impedance for the adapter design has been developed using a modal analysis method. Also, design parameters to improve the end-launched adapter have been investigated. Numerical and experimental results of the proposed model have been comp...

On the basic of fractal theory and folded technique, a miniature antenna for 2.45 GHz radio frequency identification (RFID) tag applications is designed and analyzed in the present paper. In order to realize the miniaturization of tag antenna, a Hilbert fractal structure is used. Impedance matching between antenna and IC chip is of great importance for improving tag performances. A folded techn...

Typically two configurations are used for energy harvesting with different advantages: piezoelastic and piezomagnetoelastic. Best performance of the piezoelastic configuration is when the excitation frequency is close to the resonance frequency. If the input frequency slightly deviates from the natural frequency, the generated power is severely decreased. To tackle the problem, the piezomagneto...

Fine-scale temporal organization of cortical activity in the gamma range (∼25-80Hz) may play a significant role in information processing, for example by neural grouping ('binding') and phase coding. Recent experimental studies have shown that the precise frequency of gamma oscillations varies with input drive (e.g. visual contrast) and that it can differ among nearby cortical locations. This h...

Abstract—In this work, a millimeter wave microstrip frequency-mixer design based on graphene is presented. The desired frequency mixing behavior is obtained using a nonlinear component consisting in a microstrip line gap covered by a graphene layer. The circuit includes microstrip filters that have been designed to obtain a high isolation between the input and output ports. The nonlinear behavi...

A study of Z(f), the input impedance of the Boehm flute, measured from 200 Hz to 12.5 kHz shows the expected set of strong resonances in the frequency range that corresponds to fundamental frequencies of the playing regime. These frequencies are below the expected cut-off frequency (due to an array of open tone holes) for propagation along the bore of the flute. Above this frequency, in a range...

By varying parameters that control nonlinear frequency compression (NFC), this study examined how different ways of compressing inaudible mid- and/or high-frequency information at lower frequencies influences perception of consonants and vowels. Twenty-eight listeners with mild to moderately severe hearing loss identified consonants and vowels from nonsense syllables in noise following amplific...