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In this paper, we present a novel miniaturized MNG (μ-negative) metamaterial loaded cylindrical cavity resonator based on the existence of surface waves at the interface between a metamaterial and an ordinary medium. First, we formulate the general dispersion relation for such a resonator and we show that this configuration may in principal provide the miniaturization possibility. A category of settings which provide maximum degree of miniaturization are determined. Quality factor variations are also calculated theoretically and finally a design example with the resonant frequency of about 1.39GHz, 94% miniaturization, and a relatively high quality factor of about 4500, comparing with the other miniaturized metamaterial resonators, is presented and also numerically simulated. The simulated results verify the accuracy of analytical calculations. [ABSTRACT FROM PUBLISHER]

Two pattern reconfigurable slot antennas on the circumference of metallic cylindrical cavity are studied in this paper. The first one is designed to work in 5.8GHz Industrial, Scientific and Medical (ISM) band with four slots curved around the metallic cylindrical cavity. There is one switch (currently metallic tape for proof of concepts) in each slot to achieve the reconfiguration of four different radiation patterns. The second antenna is designed for applications of Dedicated Short Range Communications (DSRC). Its central frequency is 5.88GHz with a bandwidth of 75MHz which is used in Intelligent Transportation System (ITS) applications. Reconfiguration of two different radiation patterns is realized. Simulations and analytic studies of these two reconfigurable antennas are done in this paper. Good results are achieved. [ABSTRACT FROM PUBLISHER]

A number of phenomena related to the electron cyclotron resonance ion sources (ECRIS) has been better understood recently by means of the improvement of comprehension of the coupling mechanism between microwave generators and ECR plasma. In particular, the two frequency heating and the frequency tuning effect, that permit a remarkable increase of the current for the highest charge states ions, can be explained in terms of modes excitation in the cylindrical cavity of the plasma chamber. Calculations based on this theoretical approach have been performed, and the major results will be presented. It will be shown that the electric field pattern completely changes for a few MHz frequency variations and the changes in ECRIS performances can be correlated to the efficiency of the power transfer between electromagnetic field and plasma. [ABSTRACT FROM AUTHOR]

An S-band high average power broadband MBK with peak power of 500kW, average power of 30kW and relative bandwidth of 10% is being developed in the Institute of Electronics, Chinese Academy of Sciences (IECAS). Two types of RF interaction system, cylindrical cavity and coaxial cavity are going to be used for getting required performance. The calculation results and relative technical problems for developing this MBK will also be given. [ABSTRACT FROM PUBLISHER]

Summary form only given. Three-dimensional particle-in-cell simulation has confirmed an interaction between a relativistic electron beam and nonaxisymmetric cavity modes, which leads to amplification of the cavity modes. When a relativistic electron beam is injected into a cylindrical cavity, its transverse motion excites nonaxisymmetric electromagnetic modes such as TM110 or TE112. The physical effect exploited and optimized is that of the beam-breakup instability important in high-current accelerator cavity design. Coupling the instability with the transit-time effect of the electron beam in the cavity, rapid exchange of energy between the electron beam and the preselected electromagnetic mode can occur and microwave power can then be extracted. Under optimal conditions, the linear growth time of the cavity mode at 2.44 GHz is expected to be about 3 ns. In addition, the transit-time resonance naturally leads to very narrowband output with typical wavelengths in the range of 1-10 cm depending on the cavity radius. A comparison of the linear growth rate of the TM110 mode with a linear theory prediction for different lengths of the cavity has been made. Simulation results show a slight shift in the cavity length for maximum growth [ABSTRACT FROM PUBLISHER]