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991.
Chih-Wei Yang Yean-Kuan Fang Shih-Fang Chen Chun-Yu Lin Ming-Fang Wang Yeou-Ming Lin Tuo-Hung Hou Liang-Gi Yao Shih-Chang Chen Mong-Song Liang 《Electronics letters》2003,39(5):421-422
The electrical properties of polysilicon gate MOS capacitors with hafnium silicate (HfSiO) dielectric, with and without NH/sub 3/ nitridation, were investigated. The results show that with NH/sub 3/ nitridation prior to deposition of HfSiO can effectively tune the flatband voltage close to that of conventional oxide and significantly improve the leakage properties over SiO/sub 2/ (three orders reduction). Furthermore, the excellent interface quality has been evidenced by the result of immunity against soft breakdown with NH/sub 3/ nitridation. 相似文献
992.
Wang Hongyu 《Microelectronics Reliability》1989,29(3)
The theory of reliability optimum link allocation (ROLA) is a theory through which the ROLA in a system can be achieved in accordance with the reliability size relations of the system's links. This paper deals with its theory and application in maintainable systems after the reliability index has been extended into the availability index. In conclution its feasibility has been proved with the illustration of a pratical power system. 相似文献
993.
994.
A digital calibration technique for an ultra high-speed folding and interpolating analog-to-digital converter in 0.18-μm CMOS technology is presented.The similar digital calibration techniques are taken for high 3-bit flash converter and low 5-bit folding and interpolating converter,which are based on well-designed calibration reference, calibration DAC and comparators.The spice simulation and the measured results show the ADC produces 5.9 ENOB with calibration disabled and 7.2 ENOB with calibration enabled for high-frequency wide-bandwidth analog input. 相似文献
995.
TMS320VC5402的高性能、低功耗特点使其广泛适用于需要脱机运行的内嵌式系统。为实现脱机运行,其片内掩膜ROM带有一个引导装载程序bootloader,可以实现对用户程序的多种引导装载。文中介绍了TMS320VC5402片内bootloader的引导原理,给出了并行引导方式的设计方案。 相似文献
996.
The unique characteristics of opportunistic networks (ONs), such as intermittent connectivity and limited network resources, makes it difficult to support quality of service (QoS) provisioning, particularly to guarantee delivery ratio and delivery delay. In this paper, we propose a QoS-oriented packet scheduling scheme (QPSS) to make decisions for bundle transmissions to satisfy the needs for the delivery ratio and delivery delay constraints of bundles. Different from prior works, a novel bundle classification method based on the reliability and latency requirements is utilized to decide the traffic class of bundles. A scheduling algorithm of traffic class and bundle redundancy is used to maintain a forwarding and dropping priority queue and allocate network resources in QPSS. Simulation results indicate that our scheme not only achieves a higher overall delivery ratio but also obtains an approximate 14% increase in terms of the amount of eligible bundles. 相似文献
997.
998.
采用简单的双台面工艺制作了完全平面结构的5个单元、10个发射极指大面积的SiGe HBT.器件表现出了良好的直流和高频特性,最大电流增益β为214.BVCEO为9V,集电极掺杂浓度为1×1017 cm-3,厚度为400nm时,BVCBO为16V.在直流偏置下IC=30mA,VCE=3.0V得到fT和fmax分别为18.0GHz和19.3GHz,1GHz下最大稳定增益为24.5dB,单端功率增益为26.6dB.器件采用了新颖的分单元结构,在大电流下没有明显的增益塌陷现象和热效应出现. 相似文献
999.
1000.
Most existing two dimensional(2-D)angles of arrival(AOAs)estimation methods are based on the assumption that the signal sources are point sources.However,in mobile communications,local scattering in the vicinity of the mobile results in angular spreading as seen from a base station antenna array.In this paper,we consider the problem of estimating the 2-D AOAs of spatially distributed sources.First we perform blind estimation of the steering vectors by exploiting joint diagonalization,then the 2-D AOAs are obtained through two fast Fourier transforming of the estimated steering vectors.Simulations are carried out to illustrate the performance of the method. 相似文献