A comparative study of two techniques for improving power‐handling capability of CMOS T/R switches

This article proposes an asymmetric topology for transmit/receive (T/R) switches and more importantly presents a comparative study of both LC‐tuned and resistive body‐floating techniques for improving the power‐handling capability of the T/R switches in the same 0.18‐μm triple‐well CMOS. It is shown from simulations and measurements that the switches adopting either technique achieve comparable performances. For instance, the switch employing the LC‐tuned body‐floating technique exhibits insertion loss of 1.5 dB, isolation of 23.5 dB, and power‐handling capability of 22.5 dBm at 5.2 GHz, whereas the switch using the resistive body‐floating technique exhibits insertion loss of 1.3 dB, isolation of 24 dB, and power‐handling capability of 22.2 dBm, respectively. Therefore, one can conclude that the asymmetric topology with the resistive body‐floating technique is more suitable for designing T/R switches for wireless local area network applications as it consumes smaller silicon area. © 2010 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2010.     

HALT技术在变频器中的应用初探

HALT技术可在产品设计阶段快速消除设计缺陷,缩短研发时间和成本,迅速提高产品的质量和固有可靠性。本文从HALT试验的背景出发,介绍了HALT试验的基本原理和意义。在对HALT箱各方面性能验证的基础上,针对我司11kW变频器,详细讲述了HALT试验的具体操作过程。     

A Faà di Bruno Hopf algebra for a group of Fliess operators with applications to feedback

A Faà di Bruno type Hopf algebra is developed for a group of integral operators known as Fliess operators, where operator composition is the group product. Such operators are normally written in terms of generating series over a noncommutative alphabet. Using a general series expansion for the antipode, an explicit formula for the generating series of the compositional inverse operator is derived. The result is applied to analytic nonlinear feedback systems to produce an explicit formula for the feedback product, that is, the generating series for the Fliess operator representation of the closed-loop system written in terms of the generating series of the Fliess operator component systems. This formula is employed to provide a proof that local convergence is preserved under feedback.     

电网智能综合补偿系统的设计

电网智能综合补偿系统可根据电网的动态变化情况,对电网的电压、功能率因数、谐波及三相不平均等因素实现综合补偿,文中详细介绍了这一基于８０Ｃ１９６的智能控制系统的基本结构和软硬件设计思想,实验结果表明了该系统的可行性和智能控制方法的有效性。     

江苏广电网站IDC双线路网络方案浅析

新落成的江苏广电城将即将投入使用,江苏广电网站搬入大楼全新的IDC机房。与广播、电视并列为江苏广电总台三大宣传阵地的广电网站由于受困于中国南北方网络瓶颈的限制,经常造成网络视音频节目传播不畅,所以同时接入电信和网通成为解决问题的必要手段。此文首先对IDC双线路关键技术进行了概述,然后着重介绍了根据防火墙接口地址制定策略路由、实现双线路的方法。     

智能电源系统在信号领域中的应用

随着轨道交通的发展,信号设备要求具备智能化、模块化、自动化、网络化的智能电源系统。针对信号系统的发展对智能电源系统的要求,阐述了智能电源系统在智能化、模块化、自动化三方面的应用。介绍了目前智能电源系统所采用各种不同的技术方案,并论述了方案的优缺点,总结了目前存在的问题和发展方向。     

A stable multimodel scheme control for the regulation of the transient behavior of a tunnel-diode trigger circuit

A multimodel scheme is designed for a triggering tunnel-diode circuit. The scheme improves the transient behavior during the transition time period after switching from a stable system equilibrium point to another one which is known as a triggering process. Each model is obtained by a linearization of the circuit near an equilibrium point. Moreover, each of these models can be described as a combination of two other transfer functions describing the linearized plant behavior near two different equilibrium points. The scheme chooses online the model with the best tracking performance in order to generate the control law. Different reference transfer functions are proposed with the aim of generating the desired transient in the triggering process. Some simulations show the usefulness of this scheme.     

Espaces métriques rationnellement présentés et complexité, le cas de l'espace des fonctions réelles uniformément continues sur un intervalle compact

We define the notion of rational presentation of a complete metric space, in order to study metric spaces from the algorithmic complexity point of view. In this setting, we study some representations of the space C[0,1] of uniformly continuous real functions over [0,1] with the usual norm: ||f||_∞ = Sup{|f(x)|; 0x1}. This allows us to have a comparison of global kind between complexity notions attached to these presentations. In particular, we get a generalization of Hoover's results concerning the Weierstrass approximation theorem in polynomial time. We get also a generalization of previous results on analytic functions which are computable in polynomial time.     

一种智能光纤位移传感器

介绍一种用神经网络实现无级查表功能的光纤位移传感器。其非线性误差小于0．3％FS。具体介绍了硬件原理和使用神经网络的方法。     

一种嵌信式微机数据采集系统的实现

主要讨论一个嵌入式微处理机数据采集系统的软／硬件设计方案。