一种具有自主知识产权的宽带电路交换核心芯片

引言中国建设中的高性能宽带信息示范网(3TNet)集成了T比特级高速光传输、T比特级自动交换传送网络、T比特级双栈路由器和宽带流媒体、多媒体应用支撑环境。基于波分复用技术(WDM),传输容量可扩展到160×10Gb/s或80x40Gb/s,敷设于省际和省内干线。面对如此高的带宽和复杂的业务要求,宽带电路交换就成为其必然要求。开发具有中国自主知识产权的宽带电路交换核心芯片是开发具有自主知识产权高性能宽带信息示范网络设备的物质基础。数字交叉连接芯片的功能定义数字交叉连接芯片设计的首要任务就是根据系统方案确定芯片与外围电路的功能、时…     

长途传输低速率电路开通方式的改进与传输网的智能化改造

本文通过对长途传输机房在2 Mbit/s、10 Mbit/s、100Mbit/s等低速率电路业务开通中一些问题的分析,结合现代传输网络向ASON(自动交换光网络)演进的发展趋势,提出了一种全面简化电路开通的改进方案,可大大提高电路安全性以及带宽利用率和设备端口利用率,同时有利于实现今后向ASON的平稳演进.     

基于FPGA的LVDS+RS422远距离高速通信设计与实现

针对高速信号远距离传输时存在数据可靠性下降的问题，文中设计了一种基于FPGA的软硬件结合的长线传输方案。该系统在数据传输过程中，采用NI公司的LVDS串化器芯片SN65LV1023A和SN65LV1024B作为发送与接收芯片。驱动器和均衡器的配合使用，减少了信号衰减，同时增加了电路的驱动能力和信号传输距离。在指令传输与状态反馈的电路中采用RS422通信协议，并加入保证传输可靠性的隔离芯片，极大地简化了电路。在软件方面为提高抗干扰能力，添加了8B/10B编码、指令的三判二机制和校验字，降低了误码率，提高了传输稳定性。经验证，此设计可在90 m电缆以320 Mbit/s速率零误码传输。     

千兆位双端口以太网收发器支持端对端网络应用

美国国家半导体公司最近推出的高集成度10/100/1000双端口物理层收发器,即DP83862 Gig PHYTER芯片,是一种可利用铜线传输的千兆位物理层解决方案,适用于高密度的千兆位网络交换设备、千兆位双端口网络节点卡及网络交换器上的高速上行     

硅基光子交换芯片的路由控制与性能测试

设计了电压输出范围分别是0~10 V和0~2V、调节精度为10mV的可扩展热 控电路和电控 电路,用于实现16×16光子集成芯片的工艺误差补偿和光开关切换。 描述了由硅(Si)基马赫-曾德尔(MZI)光开关单元组成的16×16光 子集成芯片控制过程,提出了基于光开关传输性能的改进环路 路由算法,此算法适用于光开关性能劣化或局部出现故障的情形。搭建了运行有改进路由算 法的光交换芯片测试系统,实验 结果表明,芯片模块的插入损耗小于33dB,串扰小于－10dB,能够实现无误码传输要求。     

基于RapidIO的相控阵短波发信系统交换单元设计

传统总线技术成为了制约短波通信系统性能进一步提升的瓶颈。RapidIO总线是一种新型嵌入式总线,具有传输效率高、系统成本低、系统稳定性好等特点。基于RapidIO技术设计了相控阵短波发信系统的交换单元,硬件上进行了系统供电电路、时钟电路和交换芯片端口电路设计;软件上主要介绍了RapidIO初始化和交换芯片的远程配置两个方面。在实际应用中实现了系统中各模块间信号的高速交换。     

新型热隔离高频信号传输结构

为了保持直调电/光转换组件激光器恒温区域温度不变，提出了一种新型的热隔离高频信号传输结构。该结构采用低热导率介质的电容来传输高频信号，有效增大了电/光转换组件中射频和激光器芯片之间的传热热阻，降低了从射频到激光器芯片恒温区之间的热传导。仿真结果表明：与传统的电路片搭接结构、金丝级联结构相比，所提传输结构使半导体制冷器的热负载分别降低了20.5%、10%，电流分别降低了100、60 m A；同时，该传输结构在2～18 GHz频段内的回波损耗最大只有-16.7 dB，具备良好的射频传输性能。     

能完成以太网第二层交换功能的富有特色的芯片组

第三代LAN芯片中小规模10和100Mbps交换XpressFlow2001以太网交换芯片组包括SC-201 XPress-Flow引擎和EA-224四端口10/l00Mbps存取控制     

蓝牙技术的心电前置放大电路定量计算及仿真

蓝牙技术是一种短距离无线通信技术,其传输距离为10~100m,为利用蓝牙技术实现无线短距离的心电实时监护系统,设计了一种以二级放大器构成放大电路,作为便携式心电监测系统的模拟放大部分,对该电路进行了定量的计算和仿真,经实验证明该电路灵敏度高、稳定性好,实现了将人体表皮的缓变微弱信号放大送到A/D中,最后通过蓝牙芯片发射出去。     

千兆自适应以太网交换机设计

基于千兆以太网交换控制芯片BCM53114S和物理层芯片BCM54684设计自适应以太网交换机。完成了系统设计设计,包括核心控制模块、复位模块、电源模块、配置模块等,并进行了系统统调测试。本设计突出的特点是千兆以太网对现有10/100 M以太网的兼容性、芯片高度集成、组网简单、具备生成树功能、自动虚拟局域网（VLAN）切割以及快速故障侦测和修复功能。相对同类产品,这里方案芯片整合度很高,模块化架构使得硬件线路设计比较简单,为数据的高速稳定传输和电磁辐射的抑制提供保证。     

Nanomechanical switches for power saving in CMOS applications

The performance of a nanomechanical switch for integration with complementary metal-oxide-semiconductor electronics to reduce idle power consumption is presented. The DC performance shows a leakage current less than 100 fA, a through current of 10 μA, and <1 mV/decade subthreshold slope. The operating voltage of the switch was approximately 13.2 V. The switch closure was measured at approximately 100 μs, while the switch open was measured at less than 100 ns. A path forward is presented to reduce the operating voltage of future switches to 3.7 V and decrease the switching time to 27 ns.     

Thin-film persistent current switch

We have developed a fast, low power heat switch for switching a niobium thin film between the normal and superconducting state. The sputtered niobium film (400 nm thick, 100 /spl mu/m wide) has a critical current density of 5/spl times/10/sup 10/ Am/sup -2/. Switching is produced by joule heating a small section of the niobium film with a titanium thin-film resistor. With the heat switch in vacuum, the minimum heater power needed to switch to the normal state was 4.5/spl times/10/sup -5/ W. A simple three-dimensional thermal model shows that the minimum power is primarily determined by the thermal conductivity of the substrate. We have achieved response times less than 10/sup -6/ s.     

电磁驱动推拉式射频MEMS开关的设计与制作

提出了一种新型电磁驱动推拉式射频MEMS开关。针对传统静电驱动单臂梁开关所需驱动电压大、恢复力不足等问题,设计了一种推拉式开关结构,降低了驱动电压(电流),提高了开关的隔离度,同时实现了单刀双掷的功能。单晶Si梁由于自身无应力,解决了悬臂梁残余应力引起的梁变形问题。通过理论计算和有限元分析,优化了开关设计尺寸,在外围永磁铁磁感应梯度dB/dz=100T/m,在线圈通入100mA电流的驱动下,单晶Si扭转梁末端可以获得约10μm的弯曲量,满足开关驱动要求。给出了开关的详细微细加工流程,对开关的传输参数进行了测试,在10GHz时隔离度为-40dB.     

一种数字CMOS工艺制造的10位100MS/s流水线ADC

介绍了采用0.18μm数字工艺制造、工作在3.3V下、10位100MS/s转换速率的流水线模数转换器。提出了一种适用于1.5位MDAC的新的金属电容结构,并且使用了高带宽低功耗运算放大器、对称自举开关和体切换的PMOS开关来提高电路性能。芯片已经通过流片验证,版图面积为1.35mm×0.99mm,功耗为175mW。14.7MS/s转换速率下测得的DNL和INL分别为0.2LSB和0.45LSB,100MS/s转换速率下测得的DNL和INL分别为1LSB和2.7LSB,SINAD为49.4dB,SFDR为66.8dB。     

KS8993型高性能交换电路及其应用

KS8993是美国KENDIN公司开发的包含3端口10/100物理层收发器的高性能快速以太网交换电路.详细介绍KS8993的主要功能、特点和主要接口,给出了KS8993在IP电话中的应用实例.     

High-repetition rate sealed-off pseudospark switches for pulsedmodulators

Experimental results of high-repetition-rate pseudospark switch testing are reported. Typical test parameters are hold-off voltage of about 20 kV, peak currents on the order of 10 kA, and pulse durations between 50 and 100 ns. The discharge circuit, with discrete ceramic capacitors up to 10.8 nF total, produced a ringing discharge with peak currents on the order of 10 kA. Current reversal under these conditions was up to 80% of the peak current. A sealed-off, ceramic-metal pseudospark switch with integral deuterium reservoir tested in this setup achieved repetition rates of up to 1.8 kHz without latching or triggering failures. Some 10⁷ shots have been performed without degradation of the switch performance     

64-Gb/s highly reliable network switch (RHiNET-2/SW) using paralleloptical interconnection

RHiNET-2/SW is a network switch that enables high-performance optical network based parallel computing system in a distributed environment. The switch used in such a computing system must provide high-speed, low-latency packet switching with high reliability. Our switch allows high-speed 8-Gb/s/port optical data transmission over a distance of up to 100 m, and the aggregate throughput is 64 Gb/s. In RHiNET-2/SW, eight pairs of 800-Mb/s×12-channel optical interconnection modules and a one-chip CMOS ASIC switch LSI (a 784-pin BGA package) are mounted on a single compact board. To enable high-performance parallel computing, this switch must provide high-speed, highly reliable node-to-node data transmission. To evaluate the reliability of the switch, we measured the bit error rate (BER) and skew between the data channels. The BER of the signal transmission through one I/O port was better than 10^-11 at a data rate of 800 Mb/s ×10 b with a large timing-budget margin (870 ps) and skew of less than 140 ps. This shows that RHiNET-2/SW can provide high-throughput, highly reliable optical data transmission between the nodes of a network-based parallel computing system     

Cascadability of large-scale 3-D MEMS-based low-loss photonic cross-connects

The performance of cascaded low-loss (<3.5 dB) 256/spl times/256 three-dimensional microelectromechanical system (3-D MEMS) photonic cross-connects (PXCs) is experimentally investigated in a recirculating loop. After 60 transitions through the PXC, a power penalty of 1.7 dB is observed, which is attributed to the accumulation of the low polarization-dependent loss in the optical switch. The use of 3-D MEMS PXCs as a wavelength-selective switch (WSPXC) for transparent all-optical networks is also demonstrated. Measured Q-factors for all 16 100-GHz-spaced wavelengths at 10 Gb/s over eight spans of 75-km single-mode fiber and eight transitions through the WSPXC nodes are better than 17 dB.     

Using a packet switch for circuit-switched traffic: a queueingsystem with periodic input traffic

Consideration is given to the effects of time-multiplexed stream traffic on the performance of a store-and-forward packet switch. Substantially reducing the amount of buffering in the switch results in only a small probability that an existing circuit will be disrupted during the length of its connection. For example, with a circuit-switched frame of length 1000 and 100% loading, reducing the buffer size from 999 packets to 83 results in only a 10^-6 circuit-disruption probability     

A 100-channel optical FDM transmission/distribution at 622 Mb/sover 50 km

A 100-channel optical frequency-division multiplexing (FDM) transmission/distribution experiment at 622 Mb/s is demonstrated for a fiber length of 50 km. The feasibility of a polarization-insensitive waveguide frequency selection switch for 10-GHz intervals and a frequency-shift-keying (FSK) direct-detection scheme employing a Mach-Zehnder filter is verified. The demodulation circuit employs a Mach-Zehnder filter and a balanced receiver, which utilizes optical power more efficiently than the Fabry-Perot filter. No receiver sensitivity degradation is observed due to interchannel crosstalk of the 128-channel tunable waveguide frequency selection switch (FS-SW) or fiber four-wave mixing for transmissions over a 50-km-long nondispersion-shifted (NDS) fiber and a 26-km-long dispersion-shifted (DS) fiber