The collective Thomson scattering (CTS) is one of the most promising methods for evaluating the ion velocity distribution function. The study of CTS diagnostic has been started utilizing the gyrotron and antenna/transmission systems installed in LHD for high power local electron heating. One of the high power gyrotrons at 77 GHz is selected as a probing power source and a set of highly focused ...

In this paper a comparison between theoretical calculations and experimental measurements of helicon wave coupling by a partial-tum shielded antenna in a toroidal heliac is presented. Despite the complicated heliac geometry, the wave dispersion, field profiles, and antenna radiation resistance are described well by a cylindrical uniform plasma theory. It also presents a simple formula relating ...

Degradations of reliability caused by plasma induced damage (PID) have become a significant concern with miniaturizing a device size. In this paper, we measure frequencies of ring oscillators with an antenna structure on a single stage. PID is relieved by connecting an antenna to a drain because charge flows to a substrate. The difference of initial frequencies is 0.64 % between structures whic...

A novel process for monolithic integration of RF MEMS switches with three-dimensional (3-D) antenna elements on a microwave laminate printed circuit board (PCB) is presented. This process calls for a low temperature (90-170C) high-density inductively coupled plasma chemical vapor deposition (HDICP CVD) technique that allows the choice of any PCB substrate, such as RO4003-FR4 (εr=3.38, tanδ=0.00...

As semiconductor technology enters the deep submicron era, reliability has become a major challenge in the design and manufacturing of next generation VLSI circuits. In this paper we focus on one reliability issue-the antenna eeect in the context of 3-layer channel routing. We rst present an antenna effect model in 3-layer channel routing and, based on this, an antenna eeect cost function is pr...

In this paper a particle swarm optimization (PSO) algorithm is presented to design a compact stepped triangle shape antenna in order to obtain the proper UWB bandwidth as defined by FCC. By changing the various cavity dimensions of the antenna, data to develop PSO program in MATLAB is achieved. The results obtained from the PSO algorithm are applied to the antenna design to fine-tune the bandwi...

Proof of concept of a cavity backed slot antenna based on inverted microstrip gap ‎waveguide (IMGW) technology is presented. Since the antenna is operating based on the ‎first resonating mode of the cavity, it is more compact compared to the ordinary cavity ‎backed slot antennas in which the second cavity mode is used for radiation. Furthermore, ‎the proposed antenna element introduces lower lo...

In this paper, a new antenna is presented which has an application in cellular telecommunication systems. The designed antenna works at the frequency range of 1900-2600 MHz which is able to cover 2G, 3G and 4G (LTE) services of the cellular telecommunication. In this paper, the micro-strip structure has been used to design the antenna. The shape of the patches is triangular where a peripheral r...

In this paper, a new method for designing an active dual-band dipole antenna is proposed. The operating frequencies of the proposed antenna are 150 and 450 MHz that are usually used in military applications. Using a series stub is the main idea in the proposed dual-band antenna, where it makes an independent resonance frequency higher than the main resonance frequency of a conventional dipole. ...