面阵数字波束形成和对多目标跟踪的研究

用计算机仿真研究面阵天线数字波束形成（DBF）和对多目标跟踪。主要内容包括方阵列天线的方向图、圆阵列天线的方向图、圆阵列天线多目标的跟踪、跟踪前的初始搜索。文中对各种情况下面阵天线的阵因子方向图作了详细的数学分析,建立了相应的模型并进行了计算机仿真。     

Imaging devices using the charge-coupled concept

A unified treatment of the basic electrostatic and dynamic design of charge-coupled devices (CCD's) based on approximate analytical analysis is presented. Clocking methods and tradeoffs are discussed. Driver power dissipation and on-chip power dissipation are analyzed. Properties of noise sources due to charge input and transfer are summarized. Low-noise methods of signal extraction are discussed in detail. The state of the art for linear and area arrays is presented. Tradeoffs in area-array performance from a systems point of view and performance predictions are presented in detail. Time delay and integration (TDI) and the charge-injection device (CID) are discussed. Finally, the uses of the charge-coupled concept in infrared imaging are discussed.     

Quantum functional devices: resonant-tunneling transistors,circuits with reduced complexity, and multiple valued logic

Recent advances in the area of quantum functional devices are discussed. After a discussion of the functional device concept, resonant-tunneling bipolar transistors (RTBTs) with a double barrier in the base region are described. Design considerations for RTBTs with ballistic injection and the first observation of minority-electron ballistic RT are presented. RTBTs using thermionic injection and exhibiting a high peak-to-valley ratio at room temperature in the transfer characteristics are also described. Multiple-state RTBTs and their DC and microwave performance are then discussed. Circuit applications of RTBTs also are discussed. It is shown that RTBTs allow the implementation of many analog and digital circuit functions with a greatly reduced number of transistors and show considerable promise for multiple-valued logic. Experimental results on frequency multipliers and parity bit generators are presented. Analog-to-digital converters are memory circuits are also discussed. Two novel superlattice-base transistors are reported. Negative transconductance is achieved by suppression of injection into minibands. Gated quantum-well RT transistors are also discussed     

Optical fibers reach into homes

The replacement of the standard series-connected pair of twisted copper wires that connects each home to the telephone network today by optical-fiber cabling that can handle broadband services is discussed. The technologies needed for the fiber to the home, which are dominated by such considerations as bit rates, network architecture, and power dissipation, are discussed. Various combinations of services and technologies that are currently undergoing trials are described. Future evolution into broadband networks is discussed     

液晶物理

首先讨论了大系数液晶材料具有抗磁性的原因；然后讨论了向列相液晶、扭曲盒液晶和胆甾相液晶在磁作用下产生的Freedericks转变；最后讨论了磁相干长度。     

液晶物理──第四章 磁场对液晶的作用

首先讨论了大系数液晶材料具有抗磁性的原因; 然后讨论了向列相液晶、 扭曲盒液晶和胆甾相液晶在磁作用下产生的Freedericks转变; 最后讨论了磁相干长度。     

卫星目标光学测量大气折射修正

本文从实测的大气参数廓线出发,讨论了对卫星目标进行光学定位测量时,进行大气折射误差修正时的几个问题,如大气色散、大气湍流和大气水平不均匀性等对折射修正的影响。首先计算了不同仰角下卫星目标光学测量的大气折射修正量的大小,讨论了用不同波长测量时大气色散所造成的修正量的偏差。同时还讨论了大气湍流、大气水平不均匀以及大气条件及昼夜变化等气象因素所引起的折射修正误差。     

Optical fiber cables for subscriber loops

The use of single-mode optical fiber cables in the local network is discussed. For various network structures, cable constructions with loose buffered fibers, ribbon, and V-groove elements are discussed. For star networks, cables with up to 2000 fibers are described. Cables for bus/star networks are also discussed. Splicing techniques and enclosures are considered. It is concluded that only mass splicing technologies with ribbons will lead to the required results     

Distance measures and asymptotic relative efficiency

The relationship between distance measures and asymptotic relative efficiency is discussed. It is shown that the ratio of the Bhattacharyya distance orJdivergences of two test statistics is equivalent to asymptotic relative efficiency. Two-input systems are discussed as examples, and the performances of the polarity coincidence correlator (PCC) and the correlator are discussed in terms of the distance measures of reduced data.     

High-density magnetic recording heads

This paper outlines the important dimensions and parameters of high-density heads and discusses why each is important and how they are related. Among factors discussed are: head-to-media spacing, record gap size, media coercivity and remanence, record demagnetization fields, record gap-edge saturation in ferrite, metal, metal-in-gap, and thin-film heads, and head wear. Gap-edge straightness is discussed. Magnetoresistive read heads are described. Vertical recording and pole-type heads are discussed. Principle sources of head noise are outlined.     

Infrared focal plane array technology

Requirements for infrared focal plane arrays (IRFPAs) for advanced infrared imaging systems are discussed, and an overview is given of different IRFPA architectures. Important IR detector structures, including photoconductive, photovoltaic, metal-insulator-semiconductor (MIS), and Schottky barrier, are reviewed. Infrared detector materials and related crystal-growth techniques are discussed, emphasizing applicability to IRFPA designs and performance. Three types of input circuit used to couple the detector to the readout circuitry are discussed, namely, direct injection, buffered direct injection, and gate modulation. An overview is given of several readout techniques, including the CCD, MOSFET switch, CID, and CIM. Also discussed are related onchip signal processing topics as well as questions regarding producibility and array implementation     

IP网络组播技术的新发展

本文综述了IP网络中组播实现体制和技术的新发展。首先．对在IP层实现组播的体系结构——IP组播进行了深入的探讨，分析、比较了IP组播两种业务模型——标准业务模型和确定源节点业务模型，讨论了IP组播存在的问题和发展趋势。接着，对应用层实现组播的体系结构进行了讨论，描述了应用层组播体制的主要功能和机制，对主要的几个应用层组播方案进行了比较，探讨了应用层组播体制的优缺点。最后对未来Internet中组播业务的实现提出了一些看法。     

Control of mode-switching in an active antenna using MESFET

New techniques of realizing mode-switching in an active antenna by using a MESFET are presented. Two types of control circuits are discussed. One is the control circuit using the reactance variation of the MESFET and the other is the control circuit using the resistance variation of the MESFET. The design of these two control circuits is discussed and the beam-switching phenomena of the antenna using these control circuits are compared. Important characteristics such as antenna patterns, operating frequencies and the insertion loss of the control circuits are also compared and discussed     

光互联网与IP over DWDM技术的演进

探讨了光互联网的支撑技术和演进策略,分析了IP over DWDM等关键支撑技术的难点与发展趋势。首先,比较分析了若干种典型的网络层次模型及其性能,指出IP over DWDM是实现未来宽带互联网的关键支撑技术;其次,分析了IP over DWDM的技术难点,指出全光信号处理和多协议标签交换技术是实现IP over DWDM的重要手段,并预言了在相关技术成熟后,光分组网技术将进一步推动光互联网的发展。     

Optical control of microwave semiconductor devices

The use of optically controlled devices to perform a range of circuit functions is reviewed. The optical control of amplifier performance is discussed. The optical control of two- and three-terminal oscillators and optically pumped mixers is discussed. Among the active devices treated are Gunn and IMPATT oscillators; MESFET and HEMT amplifiers, oscillators, and mixtures; and diode mixers. Future directions for research in this area are discussed     

The application of amorphous materials to computer memories

Two specific examples of the application to computer memories of order-disorder transitions in amorphous semiconductors are discussed. The particular physical changes utilized and accompanying the order-disorder transition are a resistance change and an optical change. The resistance change is applied to an electrically alterable Read-Mostly memory (RMM) and the optical change to a laser-alterable mass memory. The characteristics and mechanisms involved in each application are discussed briefly. The unique role of each memory in its respective area of applicability is described. For the RMM, the impact of manufacturing cost on array structure is discussed, and a new improved array of amorphous devices integrated with silicon is disclosed. For the amorphous mass memory, the effect of the interaction between high bit density laser addressing and practical engineering on the physical form of the first mass memory are discussed.     

飞行器的红外特性

飞行器红外特性研究对许多工程问题有重要意义。文中讨论了飞行器的三种主要红外辐射源即羽流,热空腔－羽流组合体,蒙皮的红外特性。较具体地讨论了飞机在非加力和加力状态下三种辐射源的辐射特性,包括空间特性和光谱特性。同时提供了实测数据作比较,还讨论了飞行器红外特性计算方法的发展及评估。     

串联叠加式固态脉冲调制器的设计

介绍了固态调制器电路常用的拓扑结构,讨论了开关直接串联与加法器叠加两种拓扑结构的特点。设计了基于IGBT的串联叠加式固态刚管脉冲调制器,调制器通过充电电源变压器实现电位隔离,采用6路调制单元串联叠加,并利用脉冲变压器升压至40 kV。重点讨论了该类型调制器研制中的关键技术,分析了脉冲变压器铁芯饱和现象并提出解决方法;讨论了吸收电路的计算选取,给出了有无吸收电路时,IGBT的C、E两端电压波形;分析并解决了脉冲波形过冲控制以及电磁干扰噪声抑制问题。