Lantiq发布业界最高集成度的ADSL2／2＋系统级芯片

领特公司（Lantiq）日前宣布针对全新的ADSL2／2＋终端（CPE）设计推出其XWAYARX300器件系列。该系列包括四个可满足不同系统配置的系统级芯片（SoC）版本,涵盖了从成本优化的快速以太网到功能丰富、高性能的千兆以太网系统。它们是专为支持电信运营商在全球市场上增强并拓展ADSL2／2＋服务而设计。     

NS2扩展突发性业务流：设计与实现

结合Markov调制泊松过程（MMPP）和混合泊松流,为突发性分组业务设计了Gamma调制泊松过程（GMPP）业务流模型。面向开源仿真器NS2的功能扩展,给出了纯泊松流、MMPP流和GMPP流的NS2扩展设计和实现方案,并经仿真实验进行了验证。分析表明GMPP更适用于实际业务流。     

基于STM32F103芯片的永磁同步电机变频器设计

本文介绍了永磁同步电机转子磁场定向控制（F0C）算法.并提出一种以sTM32F103ARM芯片作为控制核心的驱动系统针对变频器的软硬件设计.绘出了具体实现方法。实验结果表明.该变频器设计方案能实现永磁同步电机的驱动控制.具有实用性     

On2推出Hantro 9170 HD视频解码器

On2 Technologies公司推出第九代硬件视频编解码器设计Hantro 9170,该设计支持分辨率达全高清晰（ful HD）（1080p）、帧速60fps的多种格式视频播放,包括MPEG-1、MPEG-2、MPEG-4、Sorenson Spark．H．263．H．264。VC-1和REALVIDEO 8／9／10,以及高达66百万像素（megapixel）的JPEG静态图像。     

一种新的与偏振无关的双向2×2光开关的设计

设计了一种由偏振光分束器（PBS）、位相型空间光调制器（PSLM）、反射镜、半波片（HWP）和1/4波片（QWP）构成的2×2光开关。该光开关所用器件少,具有结构紧凑规整、功能的实现与信号光的偏振态无关以及可以完成双向交换等特点。进而通过2×2光开关的级连,设计了一种与偏振无关的4×4光开关的实验模块。     

基于J2ME／J2EE的JSON数据交换的探讨

分析JSON数据交换格式,并提出在客户端（J2ME）与服务器端（J2EE）间采用JSON数据交换格式的框架。对于轻量级应用,该框架可节省客户端的计算资源,提高网络传输速度。     

采用CORDIC算法的数控振荡器设计

基于CORDIC（坐标旋转数字计算）算法的NCO（数控振荡器）设计方法克服了传统数字下变频器查询表大的缺点,摆脱了用查表法产生离散正弦信号需要占用大量ROM资源的弊端,提高了资源的利用率,减小了硬件设计的代价。该算法使数控本振和数字混频两个功能合在一起完成,省去了2个乘法器,利用CORDIC算法CORDIC旋转的移位一相加流水结构,实现了数字下变频器的设计,其有效性通过仿真得到验证。     

一种新的2FSK信号识别方法

在信号处理中常常因为各种原因导致获取的信号并不完整。残缺信号由于其信息量小、特征不明显等特点造成处理难度大或者无法识别等困难,是信号处理领域内研究较少的内容。文章在研究分析频移键控信号（FSK）特性的基础上提出一种用于残缺二进制频移键控信号（2FSK）识别的新方法。首先将残缺的2FSK信号识别出,然后两两提取相关特征,最后根据特征门限识别出完整的2FSK信号。计算机仿真实验证明了该算法在低信噪比下具有较好的性能。     

产品

西门子推出适合基本应用的Sinamics V20变频器 2012年7月30日,西门子在中国推出一款适合基本应用的新型单机变频器,即SinamicsV20。该变频器由西门子中、德、英三国工程师共同设计研发,并在西门子数控（南京）有限公司生产。该款变频器结构紧凑、坚固耐用、调试迅速、操作简便且经济实用。     

与偏振无关1×2．2×2和2×4A由空间光开关在Clos光网络中的应用

首先,对无阻塞的Clos（2,4,2）光网络的拓扑结构和光学实现进行了理论分析;其次,利用偏振光分束器（PBS）、相位型空间光调制器（PSLM）和反射镜设计1×2、2×2和2X4光开关。进而设计无阻塞的Clos（2,4,2）光网络,并讨论了n×m型光开光的设计原则和升级能力。最后,通过实验测试,光开关的串扰最低可以达到...     

A new simplified model of the dynamics of the current-fed parallelresonant inverter

In this paper, the transient analysis of a current-fed parallel inverter, widely used in industrial applications (such as for the heating and melting of metals), is performed. A high-inductance smoothing inductor is usually connected in the input of the inverter and its load may be represented by a parallel resonant circuit characterized by high quality factor Q. To simplify the dynamic analysis of such an inverter, approximating it by a second-order switchless continuous dynamic link (i.e., RLC circuit) is suggested. The comparative analysis of the inverter and approximating circuit, whose parameters are properly chosen, shows the permissibility of such an approximation. It also shows how to assure desired aperiodic dynamic behavior. Then, by analyzing the approximating circuit, the expressions for inverter parameters are found. With these expressions, the values of a smoothing inductor, a compensating capacitance and a voltage factor, in order to ensure the aperiodic behavior of the inverter, can be calculated. The results of the proposed analysis were checked on laboratory and industrial prototypes of the above inverter. The theoretical and experimental results are in good agreement     

Si-gate CMOS devices on a Si/CaF2/Si structure

Si-gate CMOS inverter chains and 1/8 dynamic frequency dividers have been fabricated on a Si/CaF2/Si structure. A high-quality heteroepitaxial Si/CaF2/Si structure was formed by successive molecular-beam epitaxy of CaF2and Si. Transistors have been fabricated with an improved CMOS process that prevents crystal degradation during the fabrication process as much as possible. The maximum effective mobilities are about 570 and 240 cm²/V . s for n-channel and p-channel transistors, respectively. The inverter chain with an effective channel length of 2.0 µm has a delay time per gate of 360 ps. A maximum operating frequency of 300 MHz is obtained in the divider with an effective channel length of 2.5µm at a supply voltage of 5 V. These results indicate that the Si/CaF2/Si structure has potential for the fabrication of high-speed silicon-on-insulator devices.     

Dynamic Oscillation via Negative Differential Resistance in Type III Junction Organic/Two-Dimensional and Oxide/Two-Dimensional Transition Metal Dichalcogenide Diodes

Among many of 2D semiconductor-based devices, type III PN junction diodes are given special attentions due to their unique function, negative differential resistance (NDR). However, it has been found uneasy to achieve well-matched type III PN junctions from 2D–2D van der Waals heterojunctions. Here, the authors present other alternatives of type III heterojunctions, using 2D p-MoTe₂/organic n-type dipyrazino[2,3-f:2′,3′-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile (HAT-CN) and 2D p-WSe₂/n-MoO_x systems. Those junction diodes appear to well-demonstrate static and dynamic NDR behavior via resonant tunneling and electron–hole recombination. Extended to an inverter circuit, p-MoTe₂/n-HAT-CN diode enables multilevel inverter characteristics as monolithically integrated with p-MoTe₂ channel field effect transistor. The same NDR diode shows dynamic LC oscillation behavior under a constant DC voltage, connected to an external inductor. From p-WSe₂/n-MoO_x oxide diode, similar NDR behavior to those of p-MoTe₂/n-HAT-CN is again observed along with LC oscillations. The authors attribute these visible oscillation results to high peak-to-valley current ratios of their organic or oxide/2D heterojunction diodes.     

Design and analysis of power-CMOS-gate-based switched-capacitor boost DC-AC inverter

A multistage power CMOS-transmission-gate-based (CMOS-TG) quasi-switched-capacitor (QSC) boost DC-AC inverter is proposed and integrated with a boost DC-DC converter for a step-up application with AC or DC load. In this paper, using CMOS-TG as a bidirectional switch, the various topologies can be integrated in the same configuration for achieving two functions: boosting and alternating; boosting for getting a sinusoidal output in which the peak is the result of a many times step-up of the input; alternating to realize the positive/negative half sinusoidal of the output. The inverter does not require any inductive elements as inductor and transformer, so integrated circuit (IC) fabrication will be promising for realization. By using the state-space averaging technique, the large-signal state-space model of the inverter is proposed, and then both the static analysis and dynamic small-signal analysis are derived to form a unified formulation for inverter/converter. Based on this formulation, there are presented for theoretical analysis/control design, including steady-state power, conversion efficiency, voltage conversion ratio, output ripple percentage, capacitance selection, closed-loop control and stability, and total harmonic distortion (THD), etc. Finally, a six-stage QSC boost DC-AC inverter is simulated by PSPICE, and the simulations are discussed for some cases, including: 1) steady-state AC output, ripple percentage, and power efficiency; 2) transient response of the regulated inverter for load variation; 3) a practical capacitive load: electromagnetic luminescent (EL) lamp, and 4) efficiency, ripple percentage, and THD for different loads. The results are illustrated to show the efficacy of the proposed inverter.     

A Novel Single-Stage Series-Resonant Buck–Boost Inverter

A novel single-stage series-resonant buck–boost inverter (SRBBI) is proposed in this paper. The main attribute of the novel inverter topology is the fact that it generates an ac output voltage larger or lower than the dc input one, depending on the instantaneous duty cycle. This property is not found in the classical voltage-source inverter, which produces an ac output instantaneous voltage which always lower than the dc input voltage. The state-space averaging approach is used to estimate and examine the steady-state and dynamic character of the new single-stage SRBBI. The principle of operation, theoretical analysis, and experimental results of the proposed inverter, rated 500 W and operating at 40 kHz, are provided in this paper to verify the performance of the SRBBI.     

风力发电机并网控制方法的研究

目前,风力发电系统都存在并网功率不大、风力发电机与并网控制逆变器不匹配、利用效率低等问题。针对这种情况,该文提出了一种不可控整流、升压电路、全桥逆变的综合电路的方案设计,详细阐述了其工作原理。该文针对提出的方案,设计出并网功率为3kW的逆变控制系统并对其参数选取进行详细的计算、仿真和实验。仿真及实验结果表明,系统运行可靠,其稳态性能和动态性能良好,从而验证了并网控制方案的可行性和系统理论分析的正确性。     

Single chip controller for a high-switching frequency DC/AC power inverter

The design and implementation of a new controller for a DC/AC power inverter is described. The controller uses the high switching frequency sinusoidal PWM technique and achieves excellent output voltage regulation, frequency stability and dynamic response in a noiseless, light-weight and cost-effective construction. The inverter performance is analysed using experimental results as well as the harmonic analysis based on the generalized piecewise linear waveform representation. As these results indicate, most of the output power is concentrated on the fundamental harmonic component making the method suitable for use in driving inductive loads in various applications, such as photovoltaic systems.     

A High-Frequency Resonant Inverter Topology With Low-Voltage Stress

This paper presents a new switched-mode resonant inverter, which we term the $Phi_{2}$ inverter, that is well suited to operation at very high frequencies and to rapid on/off control. Features of this inverter topology include low semiconductor voltage stress, small passive energy storage requirements, fast dynamic response, and good design flexibility. The structure and operation of the proposed topology are described, and a design procedure is introduced. Experimental results demonstrating the new topology are also presented. A prototype $Phi_{2}$ inverter is described that switches at 30 MHz and provides over 500 W of radio frequency power at a drain efficiency above 92%. It is expected that the $Phi_{2}$ inverter will find use as a building block in high-performance dc-dc converters among other applications.      

基于Buck-Boost逆变器的离散滑模控制仿真研究

为了获得比较理想的正弦输出电压，优化逆变器的动态性能，文中基于Buck—Boost逆变器．采用了离散滑模变结构的控制策略。Buck—Boost逆变器可以获得比直流输入电源高或低的交流输出电压，文中阐述了其工作原理．并结合状态方程，推导出滑模面的存在条件、到达条件和稳定条件，然后对电路参数、控制系数以及控制算法进行了设计。仿真结果表明采用离散滑模控制的Buck—Boost逆变器对系统扰动和负载变化具有很强的鲁棒性，系统具有良好的动态响应。