一种具有84.8dB SFDR和72dB SNDR的14位80MS/s CMOS模数转换器

本文描述了一种基于0.35μm CMOS工艺的14位采样率80MS/s的流水线型模数转换器的设计. 所提出的电荷分享校正技术消除了与信号相关的电荷注入效应, 加上片内的低抖动时钟电路, 保证了模数转换器的高动态性能. 一种信号电容开关技术和高对称版图减小了电容失配, 确保了模数转换器的总线性度. 测试结果表明, 该模数转换器在36.7MHz输入频率下, 实现了11.6位的有效位, 84.8dB的无杂散动态范围(SFDR), 72dB的信号噪声失真比(SNDR), 在无校准情况下获得了＋0.63/－0.6 LSB的微分非线性和＋1.3/－0.9 LSB的积分非线性. 输入频率200MHz时,仍然可以保持75dB的SFDR和59dB的SNDR.     

四阶奇异摄动边值问题在自适应网格上的一致收敛分析

we study a difference scheme for the fourth-order singular pertur-bation differential equation on the Bakhvalov-Shishkin grid by Green‘‘s function.The method is shown to be uniformly convergent with respect to the perturbation parameter,of order N^-2 in the maxmum norm on Bakhvalov-Shishkin meshes.Numerical results support our theoretical results.     

燃煤循环流化床燃烧脱硫的模型预测

燃煤循环流化床燃烧脱硫的模型预测池涌，岑可法，倪明江Ｐ·Ｂａｓｕ（浙江大学能源系杭州３１００２７）关键词：循环流化床，燃烧，脱硫，模型预测一、引言循环流化床锅炉在过去十几年中得到了广泛的应用，但与此同时由于循环流化床内流体动力特性的高度复杂使得数学模...     

基于SUPL状态机的AGPS终端的软件实现

抽象语法标记(ASN.1)广泛应用于数据通信领域.AGPS技术中的SUPL协议即采用了ASN.1中的压缩编码规则(PER)进行消息、数据的编解码.文章分析了SUPL协议中各种消息及数据的ASN.1描述和PER编码规则接口,并在此基础上介绍了一种基于PDA操作系统平台,以状态机为核心的SUPL协议客户端的软件实现.     

A high performance CNFET-based operational transconductance amplifier and its applications

High performance electronic systems face several challenges in driving innovative integrated circuits when the internal transistors are scaled down below 45 nm. Carbon nanotube field effect transistors (CNFETs) are considered as excellent candidates for building energy-efficient electronic systems in the near future, due to their unique characteristics such as ballistic transport, scalability, and better channel electrostatics. In this paper, a new high performance operational transconductance amplifier (OTA) based on 32 nm CNFET devices is presented. The proposed OTA maintains a highly linear wide continuous tuning range and a wide frequency response range, enabled by splitting the linear voltage-to-current conversion and tuning two different blocks. As an application, a universal second-order transconductance-capacitor (G _m  ? C) filter realized using the OTA is introduced. Simulation results show that the CNFET-based OTA offers very a low current consumption of 2.35 μA from a ± 0.9 V power supply, achieves a bandwidth of 9.5 MHz, and has an input dynamic range of ± 0.2 V.     

Development of three-dimensional profiler for large field micro-surface topography measurement

This paper presents a large field phase-shifting interference microscope for micro-surface topographymeasurement. A PZT is used as the Z-directional phase shifter. The interference microscope is the combination of the infinity tube microscope with the Mirau two-beam interferometer. Two-dimensional precision motorized stage is aligned as the scanning system in theX- and Y-direction to extend the test surface measurement range to 12.5 mm× 12.5 mm. The minimum displacement is 0.039 μm and the overlapped proportion is 0.22. A fast stitching algorithm is proposed based on grid matching. According to the reflectivity of the core and the ferrule, the plate with the transmission/reflectivity ratio of 70/30 is selected to balance the interference intensity. The instrument is proved to be valid by actual measurement of the end surface of an optical fiber connector.     

关于移动IP的进一步研究

当前,如何在Ｉｎｔｅｒｎｅｔ中实现移动用户的无缝接入已成为Ｉｎｔｅｒｎｅｔ通信的热点之一,ＩＥＴＦ就此提出了移动ＩＰ,本文在讨论了移动ＩＰ的基本原理后,指出了它在寻径上的弱点,并就此提出了一种新的移动ＩＰ结构。     

基于物联网的电磁辐射监测系统的设计

本文将物联网技术应用于电磁辐射监测系统,设计了一种基于物联网的电磁辐射监测系统总体方案,在搭建了硬件平台的基础上设计实现了各软件模块。测试结果表明,该电磁辐射监测系统实现的功能包括电磁辐射水平监测、存储和管理监测数据、通过无线通讯设备向监测中心传输数据等,完全满足设计要求,可以用于创建中小型重点区域范围内电磁辐射监测网络。     

微腔中nc-Si/SiN超晶格的光致发光

研究了一维光子晶体微腔结构对nc-Si/a-SiNz超晶格发射的调制.一维光子晶体微腔采用两种具有不同折射率的非化学组分非晶氮化硅的周期调制结构,腔中嵌入采用激光晶化方法制备的硅量子点阵列,从Raman谱和透射电子显微镜分析得到其尺寸约为3～4 nm.从光致发光谱上观察到明显的选模作用、明显变窄的发光峰以及约两个量级的发光强度的增强.微腔对硅量子点阵列发光的调制主要表现在两个方面:共振模式的增强和非共振模式的抑制.硅量子点中位于腔共振模式的辐射跃迁被增强,非共振模式的辐射跃迁被抑制,因此位于腔共振频率处的跃迁通道成为硅量子点中唯一的辐射跃迁通道,导致光致发光谱的窄化和强度的增强.因此,在提高硅材料发光效率方面,光子晶体微腔具有非常大的应用前景.     

基于RFID和ZigBee技术的物联网实验系统硬件设计与实现

基于射频识别技术(Radio frequency identification technology,RFID)和近距离无线组网通讯技术(ZigBee:紫蜂)这两大物联网关键技术,设计以ZigBee协议作为传输协议的物联网主从节点以及RFID读写模块,得到了物联网实验系统的总体方案,并实现了一套完整的物联网实验系统硬件平台.测试结果验证了该实验系统完全满足设计要求,可以应用于教学实验,也可作为其他物联网应用系统的开发.