E. Y. Wong, C. M. Hillenbrand, J. S. Lewin, J. L. Duerk Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States, Department of Radiology, University Hospitals of Cleveland, Cleveland, OH, United States Introduction The use of MRI in minimally invasive, intravascular therapeutic procedures, has increased the need for imaging coils that provide accurate...

Mobile phone is one of the most widely used today in mobile communications. This technology is very useful for communication but this raises several problems in a situation where silence is required such as in libraries, places of worship, classrooms and others. Mobile phone jammer is a device that used to block the incoming signal to a mobile phone from the base station. If the mobile phone ja...

We used helical antenna-coupled radio frequency (RF) plasmas to study the evolution of mode transition power and electron kinetics under different applied magnetic fields argon pressures. Langmuir probe emission spectrum data indicate that discharge changes from capacitive coupling E inductive H through a strong mixed (E + H). One reason for this strongly ionization is antenna structure, which ...

A large-area planar spiral antenna has been installed on the linear laboratory device VINETA. For low radio-frequency (RF ) powers the induction coil is operated in the inductive discharge mode with typical plasma densities of n ≈ 1 · 10 m and electron temperatures of Te ≈ 5 eV. At higher RFpowers a transition to the helicon wave sustained discharge mode is observed, in which the density increa...

This paper focuses on the S-parameter method that is a basic method for measuring the input impedance of balanced-fed antennas. The basic concept of the method is summarized using the two-port network, and it is shown that the method can be enhanced to the unbalanced antennas using a formulation based on incident and reflected waves. The compensation method that eliminates the influence of a me...

In the Large Helical Device (LHD), the installation of a pair of ion cyclotron range of frequencies (ICRF) antennas from upper and lower ports is planned. These antennas are geometrically symmetrical and located side by side. By changing the current phase on the straps, the wave number parallel to the magnetic field line can be controlled. However, antenna impedances will also be changed and re...

The performance of a cellular phone commercial helical antenna at 900 MHz band, both in free space and in the presence of a human head phantom was studied. Numerical simulation of the phone model for the latter case has been performed giving 3D radiation diagrams. The effect of the phantom head on radiation diagrams is presented. The relative amount of the EM power absorbed in the head was obta...

A circularly polarized wideband reflectarray is presented using a monofilar single-turn helical antenna as reflecting element. An $11\times 11$ elements designed, simulated and measured in X-band which demonstrates wide bandwidth large-angle beam-scanning performance. Phase range of 360° obtained by rotating off-cen...