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41.
This paper presents a new low-cost RF BIST (Built-In Self-Test) scheme that is capable of measuring input impedance, gain, noise figure and input return loss for a low noise amplifier (LNA) in RF systems. The RF BIST technique requires an additional RF amplifier and two peak detectors, and its output is a DC voltage level. The BIST circuit is designed using 0.18 μm SiGe technology. The test technique utilizes output DC voltage measurements and these measured values are translated into the LNA specifications such as input impedance and gain using the developed mathematical equations. Simulation results are presented for an LNA working at 5 GHz. Measurement data are compared with simulation results to validate the developed mathematical equations. The technique is simple and inexpensive. Jee-Youl Ryu received the BS and MS degrees in 1993 and 1997 from Pukyong National University in Electronic Engineering, Pusan, South Korea respectively. He also received the PhD degree in 2004 from Arizona State University in Electrical Engineering, Arizona, USA. He is currently with Samsung SDI Co., Ltd. His current research interests include RF IC design and testing, MMIC design and testing, analog IC design and testing, passives modeling, testing and analysis, and MEMS technology. Dr. Bruce Kim received the B.S.E.E. degree from the University of California, Irvine in 1981, the M.S. degree in electrical engineering from the University of Arizona in 1985, and the Ph.D. degree in electrical engineering from Georgia Institute of Technology in 1996. He was an Associate Professor at Arizona State University until 2005. Currently, he is an Associate Professor at The University of Alabama. His current research interests include RF IC testing, MEMS integration and VLSI circuits. He has been working on SiP testing technologies, package electrical modeling, and measurements of RF IC packages. Dr. Kim is a 1997 recipient of the National Science Foundation's CAREER Award and received the Meritorious Award from IEEE. He serves as the Chair of the IEEE CPMT Society TC-Electrical Test, associate editor of the IEEE Transactions on Advanced Packaging, associate editor of Design and Test of Computers, and program committee member of Electronic Components and Technology Conference. He is a senior member of IEEE.  相似文献   
42.
设计了一种基于0.25μm CMOS工艺的共源共栅型1.3GHz的LNA。从噪声优化、增益及阻抗匹配角度详细分析了电路的设计方法,讨论了寄生电容Cgd、C_match_in及共栅管沟道宽度W2对LNA性能的影响。采用ADS软件,对W2进行扫描和对LNAS参量和噪声系数进行仿真测试结果表明:该LNA在1.3GHz的工作频率下.具有良好的性能指标,噪声系数fN为1.42dB,增益S21为13.687dB.匹配参数S11为-14.769dB,S22为-14.530dB,反向隔离度S12为-52.955dB。  相似文献   
43.
This paper presents a novel image segmentation algorithm driven by human visual system (HVS) properties. Segmentation quality metrics, based on perceptual properties of HVS with respect to segmentation, are integrated into an energy function. The energy function encodes the HVS properties from both region-based and boundary-based perspectives, where the just-noticeable difference (JND) model is employed when calculating the difference between the image contents. Extensive experiments are carried out to compare the performances of three variations of the presented algorithm and several representative segmentation and clustering algorithms available in the literature. The results show superior performance of our approach.  相似文献   
44.
许多时变步长(VSS)自适应算法已经提出用来完善标准LMS算法的性能,但实验表明这些算法容易受噪声干扰.本文介绍了一种新的变步长LMS自适应算法,这种算法保证了较小的失调,同时使算法在自适应初始阶段有较快的收敛速度.该算法的优越性在于它不受已经存在的不相关噪声的干扰.本文对该算法的收敛性和稳定性进行了分析,并将该算法应用于自适应噪声对消的仿真实验中,给出了计算机的仿真结果.  相似文献   
45.
The combination of higher quality requirements and sensitivity of high performance circuits to delay defects has led to an increasing emphasis on delay testing of VLSI circuits. In this context, it has been proven that Single Input Change (SIC) test sequences are more effective than classical Multiple Input Change (MIC) test sequences when a high robust delay fault coverage is targeted. In this paper, we show that random SIC (RSIC) test sequences achieve a higher fault coverage than random MIC (RMIC) test sequences when both robust and non-robust tests are under consideration. Experimental results given in this paper are based on a software generation of RSIC test sequences that can be easily generated in this case. For a built-in self-test (BIST) purpose, hardware generated RSIC sequences have to be used. This kind of generation will be shortly discussed at the end of the paper.  相似文献   
46.
黄宪伟 《电视技术》1998,(3):87-87,95
文章讨论了CATV系统前端载噪比(C/N)n指标的合理选取及合理利用,从而保证干线传输系统的性价比,可靠性和有效提高分配网络的效率。  相似文献   
47.
毛用才  保铮 《电子学报》1996,24(12):53-55
本文分析了由随机谐波构成的复信号高阶矩的有限数据估计,得到了高阶平稳和高阶遍历条件,给出了估计误差及其方差,以及它们大样本极限值的显式表达式。最后考虑了文献[2]中的情形,说明文献[2]中所得结果为本文的特例。  相似文献   
48.
制备软X光多层膜的转速控厚法   总被引:1,自引:1,他引:1  
本文提出了一种新的监控软X光多层膜膜厚的方法——转速控厚法,利用这种方法镀制的设计周期厚度分别为8.4和10nm,周期数达50对和30对的W/C多层膜,经小角X光衍射测试,结果表明周期厚度随机误差在0.1nm左右。  相似文献   
49.
用耦合模型法进行水质随机模拟的研究   总被引:3,自引:0,他引:3  
雒文生  宋星原 《水利学报》1995,(3):12-20,27
基于水质变化同时存在的两种规律-确定性规律和随机性规律(前者反映事物必然的内在联系,后者反映外在的随机性因素作用)。建立了一种能同时体现这两种作用的确定性与随机性相耦合的水质模型,并进行了水质变化过程及其概率分布的随机模拟。经实际计算,表明是切实可行的。  相似文献   
50.
The ideally simple situation of a single 180° Bloch wall in a single crystal already involves rather complex physical mechanisms. For a given variation of the magnetic field, two types of irreversible motion of the wall can be observed, depending on the velocity imposed to the wall and the temperature. It can move like a rigid plane, then its irreversible displacements are always larger than its thikness. It can also move by localized, small jumps thanks to its internal degrees of freedom. The features of the Barkhausen noise are different in these two kinds of motion. The transition between them occurs either at a constant temperature by increasing the velocity of the wall, or at a constant velocity by lowering the temperature. The wall can also move under the effect of thermal fluctuation, which should not be regarded as some little perturbation, but rather as an essential physical parameter which has to be taken into account in any realistic model of wall motion, and hence of “Barkhausen noise”. The random character of these phenomena allowed us to employ simple, but very useful, statistical methods. Besides, this study suggests some specific problems of “signal processing”.  相似文献   
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