大气层外末段拦截变结构制导律设计

研究拦截器大气层外拦截机动目标的末制导律设计问题.由沿空间拦截视线坐标系3个方向的相对运动方程,通过构建李亚普诺夫函数设计出了用于拦截目标存在两个方向不确定性机动的情况下的三雏变结构制导律.以可用过载以及燃料消耗为约束,通过建立关于脱靶量的性能指标函数,将全局优化粒子群算法应用于拦截制导律优化问题.仿真结果表明,变结构制导律具有较好的制导精度和鲁棒性,通过对制导律参数优化有效减少了脱靶量,应用该方法得到的参数优于传统设计方法中基于经验选取的参数.     

Explicit modelling of the double‐gate MOSFET with VHDL‐AMS

This paper presents a new compact model for the undoped, long‐channel double‐gate (DG) MOSFET under symmetrical operation. In particular, we propose a robust algorithm for computing the mobile charge density as an explicit function of the terminal voltages. It allows to greatly reduce the computation time without losing any accuracy. In order to validate the analytical model, we have also developed the 2D simulations of a DG MOSFET structure and performed both static and dynamic electrical simulations of the device. Comparisons with the 2D numerical simulations give evidence for the good behaviour and the accuracy of the model. Finally, we present the VHDL‐AMS code of the DG MOSFET model and related simulation results. Copyright © 2006 John Wiley & Sons, Ltd.     

一种基于弹道导弹导航信息的单星探测EKV技术

战略导弹中段机动是目前正在研究的一种较为有效的突防技术。为实现对大气层外杀伤拦截弹(EKV,exoatmospheric kill vehicle)的针对性、有效的机动规避,必须预先解决实时、精确获取EKV状态信息的问题。为此,设计了一种基于弹道导弹惯性导航信息的单颗红外探测卫星定位、测速方案,建立了针对EKV的单星探测定位测速模型,并基于该模型建立了仿真系统。在此基础上,在给定的不同卫星定位误差条件下对本方案的定位测速误差进行了仿真计算与分析,结果表明该方案可以实现定位、测速,具备理论可行性。     

模拟集成电路仿真中的UDSM MOSFET建模

对MOSFET器件特性、MOSFET建模方法和建模发展历程进行了回顾,重点分析了在模拟集成电路设计中较为流行的几种模型:BSIM3、EKV和SP2001模型,对其各自的优缺点进行了比较。结果表明,获得能够精确地预测高性能模拟系统的模型是很困难的;几种模型中,EKV模型在模拟集成电路的低功耗设计中具有一定的优势。     

超深亚微米工艺下模拟IC仿真的MOSFET模型

对MOSFET器件特性、MOSFET建模方法和建模发展历程进行了回顾,分析了在模拟集成电路低功耗设计中比较流行的模型(BSIM3和EKV模型),对它们进行了比较,分析其各自的优点和缺点。结果表明获得能够精确地预测高性能模拟系统的模型是很困难的,而EKV模型在模拟集成电路的低功耗设计中具有一定的优势。     

Single-layer thin-film transistor analysis and design

A set of direct current (DC) analytical equations is formulated for the analysis and design of a single-layer thin-film transistor (TFT). For a specified TFT structure, drain current is calculated as a function of drain and gate voltage (taking the source as ground) according to the Enz, Krummenacher, Vittoz (EKV) compact model. One model parameter function is required to implement this EKV-based equation, that is, drift mobility as a function of gate voltage. Drift mobility is evaluated as a consequence of accumulation layer electrostatics assessment of the TFT structure specified. In order to implement the model, three semiconductor properties (low-frequency (static) relative dielectric constant, free electron concentration, and maximum (no trapping) mobility), two structure properties (insulator capacitance density and TFT width-to-length ratio), and one physical operating parameter (temperature) must be specified. Optimal TFT mobility performance is achieved when the thickness of the semiconductor channel layer is constrained to be less than 2.22 times the channel layer Debye length such that “short-base” TFT operation obtains. Additionally, higher mobility TFT performance is obtained by selecting a channel layer with a small electron effective mass, reducing channel layer trap density, reducing channel layer thickness, reducing the free electron concentration, and/or increasing gate capacitance density.