Effects on dynamic characters of antenna structures in satellite induced by disordered parameters

A simplified dynamic model of a dish antenna in satellite is established in this article.The modelcan be easily used to analyze the dynamic behaviour of the antenna structure.In terms of the simplifiedmodel,effects on dynamic characters due to the disorder of parameters are investigated in details.Thefrequencies calculated by the simplified model accord with those computed by ANSYS.Based on the modeshapes of disordered and perfect structure,the influence law and varying trend of dynamic characters ofantenna structures in satellites produced by stiffness and mass of antenna ribs,stiffness of antenna mem-branes and angles between adjacent ribs,are obtained.The analyses in the paper indicate that the effectsby disordered parameters can not be ignored in the dynamic analysis of such structures.

High quality-performance by changing parameters of antenna array

Several antennas based on cylindrical array and uniform hexagonal array are designed and fabricated on flexible substrate-Teflon.To validate the designed prototypes,the antennas are fabricated and their performance is analyzed.The highlight scheme is to improve the signal performance and electromagnetic field distribution by appropriately changing the parameters of the antennas array,signal frequencies,and steering angles.The proposed antennas array is capable of applying shaping radiation band technique to generate tunable power and radiation domain.The distribution of the field,and the bit-error-rate transmigration coefficient characteristics are measured.The results show that the proposed scheme can achieve better performance by searching the optimal parameters of antenna array.

Thermal analysis and optimization of the EAST ICRH antenna

The ion cyclotron resonance of frequency heating（ICRH） plays an important role in plasma heating.Two ICRH antennas were designed and applied on the EAST tokamak.In order to meet the requirement imposed by high-power and long-pulse operation of EAST in the future,an active cooling system is mandatory to be designed to remove the heat load deposited on the components.Thermal analyses for high heat-load components have been carried out,which presented clear temperature distribution on each component and provided the reference data to do the optimization.Meanwhile,heat pipes were designed to satisfy the high requirement imposed by a Faraday shield and lateral limiter.

Antenna Array Structures Effect on Water-Filling Capacity of Indoor NLOS MIMO Channel

A 2-D Shooting and Bouncing Ray-tracing method （ SBR ） is used to analyze the different antenna array structure effect on the water-filling Capacity Complementary Cure ulative Distribution Functions （ CCDFS） of indoor Non-Lineof-Sight （NLOS） Multiple-Input Multiple-Output （MIMO） channel. The results have shown that in NLOS indoor environment different antenna array structures affect on the CCDFS differently. The CCDFS of MIMO systems with antenna spacing 5λ change slightly with antenna array structures and all approach the in independent and identically distribution （ i. i.d. ） rayl,eigh channel water-filling capacity. When antenna spacing decreased to 0.53., the capacities of MIMO systerns drop also, and change with antenna array structures greatly. The results on outage water-filling capacity also show that there exist a fixed relationship that i. i.d. rayleigh channel capacity is larger than the capacity equipped with linear antenna array which is larger than the capacity equipped with rectangular antenna array and the capacity equipped with circular antenna array.

Prevention of plasma-induced damage on thin gate oxides in BEOL sub-half micron CMOS processing

A comparison is made of several plasma-induced damage（PID） measurement techniques.A novel PID mechanism using high-density plasma（HDP） inter-metal dielectric（IMD） deposition is proposed.The results of a design of experiment（DOE） on Ar pre-clean minimizing PID are presented.For HDP oxide deposition,the plasma damage is minimal,assuring minimal exposure time of the metal line to the plasma using a maximal deposition to sputter ratio.This process induces less PID than classic SOG processing.Ar pre-clean induces minimal plasma damage using minimal process time,high ion energy and high plasma power.For metal etching,an HDP etch is compared to a reactive ion etch,and the impact of the individual process steps are identified by specialized antenna structures.The measurement results of charge pumping,breakdown voltage and gate oxide leakage correlate very well.On metal etching,the reactive ion etching induces less plasma damage than HDP etching.For both reactors, PID is induced only in the metal over-etch step.