超分辨重建技术及其研究进展

超高分辨成像技术一直是航天、遥感、目标识别等领域的研究热点。随着光学成像到光电数字成像的转变,如何提高CCD的几何分辨率,已成为研制高分辨光电成像系统亟待解决的问题。本文从理论和工程实现的角度介绍了超分辨成像的技术原理,分析了实现超分辨重建技术的几种方法,主要描述了微扫描和亚像元两种重建技术的实现方式,指出了目前超分辨技术存在的缺陷。最后,针对超分辨技术中无混淆重建带宽较窄的问题,提出了一种新的技术方案。该方案将光学编码技术与目前的亚像元技术相结合,可将重建带宽拓展3倍。研究结论指出：融合了光学,光电子学和信号处理的成像系统的综合设计,将是未来成像领域的一个重要研究方向。     

基于COMPASS+PD/HRLR组合的侦察导弹对海洋移动目标定位方法研究

针对现行侦察手段对敌方海洋移动目标进行地理坐标的测量方法不多,测量精度不高的问题,提出了一种利用反舰巡航导弹搭载北斗卫星定位接收机(COMPASS)、合成孔径雷达(SAR)、脉冲多普勒雷达(PD)、高重频激光测距仪(HRLR)、激光测高仪(LHD)与数据传输系统(DCS),实现对敌海洋移动目标准确识别和精确定位的方法,介绍了侦察导弹的组成,说明了定位原理,给出了物理多站连续交会定位算法模型,进行了模拟测量数据解算和误差分析。通过仿真证明,本方法简单、实用,能够满足实际工程应用的需求,可为海上远程精确打击体系提供高精度的目标位置信息。     

周期性管柱信道的声波通信技术研究综述

井下声波通信技术利用周期性管柱信道实时传输声波数据,相比于其他通信方式,具有适应性好、复杂度低、传输效率高等优点,在随钻地质导向、油水井监测等方面有广阔的应用前景,是发展智能油田的关键技术之一。该文主要综述20世纪90年代以来关于周期性管柱信道物理模型、信道容量、声信号调制与接收方法等关键问题的研究历程和主要结论,并对通信系统的设计要点与国内外相关产品的现场应用进行梳理,为后续的技术改进提供依据。     

Method of developing an all optical wavelength encoded single bit comparator exploiting four wave mixing and wavelength filtering character of nonlinear semiconductor optical amplifiers

Data Comparator is the integral part of arithmetic and logical unit of any electronic or optical data processor. Due to some inherent limitations of electronics it is not possible to obtain super fast data processing (over Terahertz limit) from electronic comparator. Again frequency encoding technique has been established as an excellent one over the other optical data encoding techniques. Semiconductor optical amplifiers (SOA) technologies have shown its potentiality of realising many all-optical systems. In this communication the authors have proposed a new all-optical wavelength encoded single bit binary comparator exploiting the four wave mixing and wavelength filtering property of nonlinear semiconductor optical amplifier.     

Next generation interatomic potentials for condensed systems

The computer simulation of condensed systems is a challenging task. While electronic structure methods like density-functional theory (DFT) usually provide a good compromise between accuracy and efficiency, they are computationally very demanding and thus applicable only to systems containing up to a few hundred atoms. Unfortunately, many interesting problems require simulations to be performed on much larger systems involving thousands of atoms or more. Consequently, more efficient methods are urgently needed, and a lot of effort has been spent on the development of a large variety of potentials enabling simulations with significantly extended time and length scales. Most commonly, these potentials are based on physically motivated functional forms and thus perform very well for the applications they have been designed for. On the other hand, they are often highly system-specific and thus cannot easily be transferred from one system to another. Moreover, their numerical accuracy is restricted by the intrinsic limitations of the imposed functional forms. In recent years, several novel types of potentials have emerged, which are not based on physical considerations. Instead, they aim to reproduce a set of reference electronic structure data as accurately as possible by using very general and flexible functional forms. In this review we will survey a number of these methods. While they differ in the choice of the employed mathematical functions, they all have in common that they provide high-quality potential-energy surfaces, while the efficiency is comparable to conventional empirical potentials. It has been demonstrated that in many cases these potentials now offer a very interesting new approach to study complex systems with hitherto unreached accuracy.     

Applied Mathematical Methods in Theoretical Physics, 2nd edn., by Michio Masujima

When Oliver Cromwell's decision to place the Post Office under the control of Parliament was ratified by Charles II in 1660, the main business of the Post Office was communication—transmission of the written word by letter. Since these days the Post Office has become responsible for many other services, either on its own account, or as an agent for other Government Departments; communication, however, is still its main business, although many new forms of it have been added during the last hundred years.

The first new form was that of the transmission of the written word in coded form by the electric telegraph; this was followed by transmission of the spoken word by telephone. Transmission of pictorial information came next: first in the slow-speed form of picture telegraphy, then in the high-speed form of television. The latest form is data transmission, the data being mostly numerical, which is associated with the growth of electronic computers over the last decade or so; the administrative and technical arrangements for data transmission by the Post Office are still in the very early stages, but this service will undoubtedly grow.     

Cutting-Edge Technologies on Broadband and Scalable Photonic-Network—Packet switched networks based on all-optical label processing—

Ultra-high speed all-optical label processing methods are proposed and experimentally demonstrated. These methods dramatically increase the label processing capability. Optical packet switch (OPS) systems and networks based on OPS nodes are expressed as an application of optical processing technologies. First, the 40 Gbit/s/port OPS prototype with all-optical label processor, optical switch, optical buffer, and electronic scheduler is described. The feasibility of OPS networks is verified by experimental demonstrations.     

Design and fabrication of AlGaAs/GaAs phase couplers for optical integrated-circuit applications

As integrated electronic circuits based on GaAs are getting faster and more complex and the relatively new fiber optic communication industry is expanding into new markets, such as shipboard communication links, the need for high-speed optical signal processing in a GaAs-based system has become increasingly evident. The economy and flexibility of fabricating both electronic and optical circuits on the same wafer promises significant increases in the computing power and speed of large distributed systems (those involving more than a few medium-density chips). The obvious medium for integration of optics with electronics is GaAs. High-speed ICs utilizing GaAs MESFETS are already in the marketplace, as are GaAs/AlGaAs laser diodes and detectors. Thus the two building blocks exist and only wait to be stacked together in a useful manner. What must hold these together is any combination of passive waveguides, modulators, switches, or optical fibers which will provide high-speed links between several electronic systems. It does not matter that these systems may be miles apart or on the same wafer: the interconnecting optical circuits are the same except for the possible insertion of an optical fiber.     

Design and fabrication of AlGaAs/GaAs phase couplers for optical integrated-circuit applications

As integrated electronic circuits based on GaAs are getting faster and more complex and the relatively new fiber optic communication industry is expanding into new markets, such as shipboard communication links, the need for high-speed optical signal processing in a GaAs-based system has become increasingly evident. The economy and flexibility of fabricating both electronic and optical circuits on the same wafer promises significant increases in the computing power and speed of large distributed systems (those involving more than a few medium-density chips). The obvious medium for integration of optics with electronics is GaAs. High-speed ICs utilizing GaAs MESFETS are already in the marketplace, as are GaAs/AlGaAs laser diodes and detectors. Thus the two building blocks exist and only wait to be stacked together in a useful manner. What must hold these together is any combination of passive waveguides, modulators, switches, or optical fibers which will provide high-speed links between several electronic systems. It does not matter that these systems may be miles apart or on the same wafer: the interconnecting optical circuits are the same except for the possible insertion of an optical fiber.     

Narrow linewidth laser diodes with broad continuous tuning range

A fast electronic frequency stabilisation scheme is presented which improves the coherence properties of near IR laser diodes substantially. The control loop is effective even under fast, wideband frequency tuning conditions, which opens up new fields of application in spectroscopy, range finding and data communication.Dedicated to Prof. Dr. Herbert Welling on the occasion of his 60th birthday     

Aerosol processing for nanomanufacturing

Advances in nanoparticle synthesis are opening new opportunities for a broad variety of technologies that exploit the special properties of matter at the nanoscale. To realize this potential will require the development of new technologies for processing nanoparticles, so as to utilize them in a manufacturing context. Two important classes of such processing technologies include the controlled deposition of nanoparticles onto surfaces, and the application of chemically specific coatings onto individual nanoparticles, so as to either passivate or functionalize their surfaces. This paper provides an overview of three technologies related to these objectives, with an emphasis on aerosol-based methods: first, the deposition of nanoparticles by hypersonic impaction, so as so spray-coat large areas with nanoparticles; second, the use of aerodynamic lenses to produce focused beams of nanoparticles, with beam widths of a few tens of microns, so as to integrate nanoparticle-based structures into microelectromechanical systems; and third, the coating of individual nanoparticles by means of photoinduced chemical vapor deposition (photo-CVD), driven by excimer lamps. We also discuss the combination of these technologies, so that nanoparticle synthesis, together with multiple processing steps, can be accomplished in a single flow stream.     

基于Android平台的USB通信技术研究

针对Android平台的USB通信技术的广阔应用前景,对Android 设备与单片机的USB通信技术进行了研究;搭建了Android设备与单片机进行USB通信的硬件平台;以Android USB Host通信技术为核心,开发了Android端与单片机端的USB应用程序;着重阐述了Android端USB应用程序的完整开发过程,给出了其所需API类的功能描述、使用方法以及程序的开发流程图、主要功能实现的关键代码;对Android开发板与单片机之间的数据通信过程进行了测试,结果表明两者通信正常,实现了Android平台下的USB通信功能。     

A novel all optical method of implementing an n-bit wavelength encoded complete digital data comparator using nonlinear semiconductor optical amplifiers

Data comparator is the integral part of arithmetic and logical unit of any electronic or optical data processor. Due to some inherent limitations of electronics it cannot be possible to obtain a super fast operation (over terahertz limit) from electronic comparators. Again wavelength encoding technique has been established as an excellent one over other existing optical data encoding techniques. Semiconductor optical amplifier (SOA) technologies have shown their strong potentiality of realizing many all-optical systems. In this communication the authors have proposed a new scheme of developing all-optical wavelength encoded n bit binary comparator exploiting the four-wave mixing, wavelength filtering, wavelength conversion and nonlinear polarization rotation capabilities property of nonlinear semiconductor optical amplifiers. The scheme can be used for comparing signed and unsigned optical binary data of any bit wide numbers as well. The comparator is especially suitable for use as a building block in a larger optical circuit, such as in an all optical telecommunications switch.     

微流体技术在电子芯片冷却中的应用研究进展

随着微电子技术向小型化集成化及高频高速方向发展,计算机芯片集成度的提高受到因电子元器件发热而引起的热障所限制,芯片冷却问题成为影响计算机进一步发展的关键因素之一。介绍了电子芯片发展的现状及主要冷却方法的发展,从冷却驱动器件、微通道结构各个角度论述了微流体技术在电子芯片冷却中的重要作用,重点介绍了微槽道冷却和微喷冷却的微流体技术特征,论述了压电泵、电渗、热管等微流体驱动技术在冷却液驱动的应用。     

The application of optoelectronic technologies to high performance electronic processor interconnects

The application of optoelectronic technologies and data transmission techniques, developed initially for the telecommunications market, to electronic processor systems offers to overcome interconnect limitations facing designers of these high performance systems. Optical interconnects offer increased data rates, low power consumption, compact size and inherent freedom from the effects of mutual coupling, line capacitance, EMI and topological constraints. This paper describes our investigation of two of the key technologies required for the practical implementation of optical interconnections, namely optoelectronic interface components (the optical bond pads), and the associated hybrid alignment techniques used in their assembly.     

All-optical method for maintaining a fixed intensity level of a light signal in optical computation

In data and image processing the role of optics is already well established. Due to inherent parallelism the optical systems run faster than its electronic counterparts. Optical nonlinear material can be used as a successful optical switch. The primary requirement for proper functioning of such nonlinear material based logic devices is a fixed intensity level of the optical signal against a specific logic state. In this communication, the authors propose a new concept to obtain a fixed intensity level of optical signal against a specific logic state for data processing. The scheme may extend a tremendous application not only to the area of all-optical computation, but also to optical communication process.     

英国冷库设计中的若干新技术剖析

根据现场考察和交流,介绍分析英国冷库氨制冷系统设计中的若干新技术.通过采用减少系统充氨量的系列新技术,可以使系统的充氨量大大减少,安全性大大提高.通过采用自动控制、高效热氨融霜、回收余热加热地坪、冷风机合理配置等新技术,可明显提高运行的能效.结合我国冷库情况,分析了适合我国借鉴的新技术.     

Energy band engineering of flexible gallium arsenide through substrate cracking with pre‐tensioned films

Flexible electronics based on the otherwise rigid conventional crystalline semiconductors is emerging as a new class of technology. However, the existing layer‐transfer approaches for implementing such technologies is mostly focused on maintaining the performance of the original device. Here we show that layer transfer through substrate cracking with a pre‐tensioned nickel film readily enables the manipulation of the electronic band structure in flexible gallium arsenide (GaAs) devices. We empirically and theoretically quantify the effect of ‘engineered' residual strain on the electronic band structure in these flexible GaAs devices. Photoluminescence and quantum efficiency measurements indicate the widening of the GaAs energy bandgap due to the residual compressive strain. The experimental results are in good agreement with our theoretical calculations. This study introduces a new way for strain engineering in flexible compound semiconductors with important implications for electronic and optoelectronic applications. (© 2016 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)     

基于PAM4制的高速垂直腔面发射激光器研究进展

短距离光互联技术在云计算、5G通信、物联网技术等方面有重要的商业应用价值。基于高速垂直腔面发射激光器(Vertical-cavity surface-emitting laser,VCSEL)与多模光纤组成链路、采用直接调制检测、并使用如四电平脉冲幅度调制(Four-level pulse amplitude modulation,PAM4)等的高阶调制模式是现阶段短距离光互联链路方案的首选。本文首先介绍了短距离光互联应用的研究现状;第二部分介绍了VCSEL的发展、结构以及动态参数;第三部分介绍了PAM4调制方法及伴随使用的各种电子技术(均衡,前向纠错,脉冲整形);第四部分介绍了提高单链路速率的波分复用(Wavelength division multiplexing,WDM)技术;最后对以高速VCSEL、多模光纤、直接调制检测、PAM4调制以及波分复用技术的短距离光互联方案应用前景做了总结和展望。     

逆Compton散射的MonteCarlo模拟

研究模拟均匀、各向同性介质内的逆康普顿散射过程的Monte Carlo方法,分析电子速度分布乘抽样法和光子散射方向分布乘抽样法的抽样效率,完善电子速度分布的直接抽样法、光子散射能量分布的乘加抽样法.通过对这四种抽样方法抽样费用的分析和比较,得出各种方法的最适条件,该方法可以模拟更高能的辐射.