一种混合集成DC/DC电源调制器的设计

介绍了一种混合集成DC/DC电源调制器的设计,并给出了实验结果。该电路包含延时电路、逻辑运算电路、驱动电路和输出电路,其主要功能是对输入的TTL控制信号进行逻辑运算和延时处理;通过驱动电路后,对 3.3 V、 5 V、 6 V、 12 V电源进行调制,可实现按规定时序为系统供电。     

一种新型光域PAM4调制器及关键性能建模分析

四级脉冲幅度调制(PAM4)在高速串行链路系统中的地位日益提高,受到越来越多的关注.传统的行波马赫-曾德尔调制器(TWMZM)的分光比为1 ∶ 1,文章提出了一种非对称光强的行波马赫-曾德尔调制器(Asymmetric Power TWMZM,AP-TWMZM),并对输入端分光比进行独立推算,得到分光比的值为4 ∶ 1.Lumerical软件的建模仿真结果表明,在插入损耗和消光比与TWMZM相当的情况下,AP-TWMZM具有更高的调制效率和更好的线性度,其线性度高达0.948.     

一种新型的S波段天气雷达发射机

叙述了最新研制的S波段天气雷达发射机构成,着重介绍了该雷达发射机采用的脉冲整形电路,交流方波灯丝供电、固态调制器等新技术,该雷达发射机技术性能和可靠性达到了新的水平。     

基于SAG和QWI结合技术的电吸收调制器与可调谐DBR激光器的单片集成

报道了基于选择区域生长和量子阱混杂结合技术的电吸收调制器与可调谐DBR激光器的单片集成.集成器件显示出了良好的静态特性:阈值电流为37mA;100mA激光器增益区偏置电流下,直流输出功率为3.5mW;当使用单模光纤耦合(耦合效率15%),调制器偏压在0～-2V之间时,静态消光比大于20dB;波长调谐范围为4.4nm,覆盖了6个100GHz间隔的WDM信道.     

A low-power sigma-delta modulator for wireless communication receivers using adaptive biasing circuitry and cascaded comparator scheme

This paper represents the low-power signal-delta (ΣΔ) modulator for wireless communication receiver applications. The 2nd-order modulator has a single-loop structure with 11 quantization levels. An adaptive biasing scheme of the operational amplifier and cascaded comparator scheme are proposed in order to save the power consumption. The DAC with three-level references including the analog ground voltage can make the modulator be implemented with half of the input capacitances without degradation of linearity characteristics with the help of dynamic element matching technique. Peak SNR values of 74 dB and 68 dB are achieved with the input bandwidths of 615 kHz and 1.92 MHz for CDMA-2000 and WCDMA applications, respectively. The modulator is fabricated in a 0.13-μm standard digital CMOS technology and dissipates 4.3 mA for a single supply voltage of 2.8 V. Jinup Lim was born in Seoul, Korea, in 1973. He received the B.S. and the M.S. degrees in semiconductor engineering from University of Seoul, Seoul, Korea, in 1999 and 2001, respectively. From 2001 to 2002, he worked in GCT Semiconductor Inc., Seoul, Korea. He is currently working toward the Ph.D. degree in Electrical & Computer Engineering at the same university. He received the Best student paper award from IEEE SSCS/EDS Seoul Chapter in 2004 and the Samsung Best paper award third prize in ISOCC 2004. His research area is the design of high-performance discrete-time / continuous-time sigma-delta modulator circuits. Joongho Choi was born in Seoul, Korea, in 1964. He received the B.S. and the M.S. degrees in electronics engineering from Seoul National University, Seoul, Korea, in 1987 and 1989, respectively. In 1993, he received Ph.D. degree in electrical engineering from University of Southern California, CA, USA. From 1994 to 1996, he worked in IBM T. J. Watson Research Center, NY, USA. In 1996, he joined the University of Seoul, Seoul, where he is currently a professor in the Department of Electrical & Computer Engineering. His research area is the design of high-performance analog integrated circuits.     

一种先进结构的数字射频存储器分析

介绍了典型数字射频存储器(DRFM)工作原理、作用、主要性能参数及影响其性能参数的因素,讨论了不同结构形式对性能参数的影响,在此基础上重点分析了一种先进结构的DRFM,阐明了该DRFM的基本工作原理、各功能模块的作用和主要特点;探讨了其采用数字正交双通道的原因以及数字双通道的几种实现方法,对DRFM的设计和应用具有一定的参考价值。     

基于混合加法CA的光学流密码系统

提出一种新的光学流加密系统。此系统用加法混合细胞自动机(CA)作密钥发生器,用CA的细胞构造空间光调制器(SLM)的阵列,一种门限器件实现所需的CA规则,整个系统可用光电混合或完全光学器件实现。模拟分析显示,用480×640像元CCD,加密速度可达到144Kbits/s,产生的密钥序列最大长度为2N-1(N为初始阵列细胞数目),直接攻击此加密系统需要的计算资源成指数性增长。     

A 8.75-11.2-GHz,low phase noise fractional-N synthesizer for 802.11a/b/g zero-IF transceiver

An ultra broadband fractional-N frequency synthesizer for 802.11a/b/g zero-IF transceiver application is presented.The mathematical models for the behavior of the synthesizer’s spur and phase noise are analyzed,and the optimization methodology is proposed.Measurement results exhibits that the frequency synthesizer’s integrated phase noise is less than 1°(1 kHz to 100 MHz)with a 4.375 GHz carrier(after divide-by-2),and the reference frequency spur is below-60 dBc operating with a 33 MHz reference clock.The frequency synthesizer is fabricated on a standard 0.13μm RF CMOS process and consumes 39.6 mW from a 1.2 V supply voltage.     

BRAQWET能带结构和优化设计参量

对 n型源区、p型势垒区和具有 δ(p+ )薄层势垒区的两种结构 BRAQWET的能带模型 ,作了严格的定量分析 ,由此可以导出设计良好器件的优化参量。这是设计 BRAQWET的理论基础     

光波调制技术的高级调制码型

Arbitrary waveform can be synthesized by two orthogonal components: in-phase and quadrature components. Thus, if we can manipulate the two components independently, various complicated modulation can be achieved. This technique is called vector modulation, which is commonly used in wireless radio communication systems where the carrier frequency is lower than 100GHz. On the other hand, in lightwave transmission systems, the carrier frequency is higher than 100THz, and the stability of the signal sources would be much poorer than in radio systems, so that the simplest modulation format (on-off-keying) was often used in commercial systems. However, recently, various modulation techniques such as quadrature amplitude modulation, etc., have been demonstrated by using precise and rapid lightwave control. In this report, we review recent progress in optical vector modulation technologies which can generate highspeed and complicated optical signals. Integrated optical modulators can synthesize multi-level signals in photonic circuits.