无人机导航技术应用与发展趋势

无人机导航系统是无人机完成给定任务的关键要素之一.本文分析了现有的导航技术和无人机导航系统应用现状.研究了不同类型无人机执行任务的环境、特点和相对应的导航方式;提出了未来无人机导航系统的发展趋势.     

无人机测绘遥感

本文阐述了无人机发展历程和我国无人机应用技术现状,论述无人机在遥感测绘领域的应用优势,描述无人机遥感在移动通信和电力行业的应用.无人机数据处理方法及其传感器的搭载是无人机遥感测绘技术的未来研究热点与研究方向,提出了无人机技术在测绘遥感领域的应用问题.     

无人机自主性概念研究

讨论了与无人机自主性有关的三组概念.介绍了一种无人机自主性的定义和作为其工程概念的自主能力等级.最后分析了无人机自主性,提出了无人机自主性的研究内容.     

无人机在电视新闻中的应用与前景

无人机是指用遥控设备或自身程序控制的无人驾驶的飞行器,无人机以计算机遥控系统为“脑”,以可见光和红外探测器为“眼”,拥有各类机载式武器以及功能设备齐全的“爪牙”.总之,无人机就是无人驾驶飞行器的统称,从技术层面给无人机分类,大概可以分为无人直升机、无人固定翼机、无人多旋翼飞行器、无人伞翼机、无人飞艇等几大类.由于无需人员驾驶、能广泛地应用于更危险的任务之中,所以无人机在社会各行各业中都有着广泛的运用.如今,无人机技术已广泛应用在侦察搜索领域.在美国,无人机技术已经被作为主要发展方向,相信若干年后,无人机技术必将成为科学领域内技术竞争的又一个领域.本文将从电视新闻的角度,叙述无人机在电视新闻中的应用,以及无人机在电视新闻应用中的前景.     

华为、中国移动为何力推“网联无人机”?瞄准低空数字化巨大市场

在科技浪潮的推动下,无人机领域发展迅猛,根据高盛研究的预测,从2016年初到2020年,无人机将有1000亿美元的市场机会.“无人机是未来大势所趋”已成业内共识,并且无人机在国内已逐步扮演多种角色,如无人机送外卖、无人机送快递、无人机参与安全巡检、无人机进行农业监测等.     

无人/有人机协同探测/作战应用研究

无人机将是今后重点发展的武器装备,而无人机和有人机协同探测/作战将是其典型应用方式.介绍了国外无人/有人机协同探测/作战的发展概况,对无人机间的协同探测、无人机与预警机协同探测和无人机与战斗机的协同作战等模式进行了探讨,分析了各协同方式对无人机平台的能力需求.通过协同探测/作战,大大扩展了无人机的使用范围,提升了信息感知能力.     

一种微型无人机机载气动连续发射装置

随着无人机技术的不断发展,无人机开始进入民用领域.但由于相关法律法规的缺失,造成民用微型无人机管理混乱,特别是消费级无人机的滥用对城市公共安全造成极大的威胁.针对这种情况,本文采用远程触发、压缩气体为动力源,可连续发射的设计原则,设计了一种轻巧灵活的无人机子弹连续发射装置,通过装配玻璃弹珠、金属球等作为子弹进行连续发射.该方案集子弹填装模块,触发模块,缓震模块,发射控制模块为一体,以无人机为搭载平台,实现对微型无人机拦截和打击,以确保了城市低空安全.此外,本文重点研究了无人机平台在子弹发射时的运动学状态,用Adams进行动力学仿真,研究微型无人机在空中进行子弹发射时的动态响应、平台的运动和受力情况,该无人机机载气动连续发射装置为反微型无人机研究提供了一种新的思路.     

一种民用小型无人机的射频指纹识别方法

随着民用无人机的普及,无人机"黑飞"事件频频发生,给公共安全带来极大隐患.为了实现对"黑飞"无人机的有效监管,通过提取遥控信号指纹特征对无人机识别是一种有效的方法.基于民用小型无人机遥控信号通常采用跳频通信这一特性,通过分形贝叶斯变点检测算法对实测无人机遥控信号的瞬态起始点进行检测,并提取信号瞬态部分所含有的指纹特征,由主成分分析法进行特征降维,最后采用多分类支持向量算法对该信号进行分类及识别.实验结果表明,采用射频指纹法能够完成无人机型号的区分以及同一型号无人机的区分.     

浅析体系作战中无人机系统频谱管理

无人机在现代战争当中占据了非常重要的地位.在作战的过程中无人机具有较为灵活,并且不会出现伤亡的优势.除此之外无人机在远距离侦察以及压制打击空中预警等方面也扮演着重要的角色.同时最重要的就是无人机的出现还为当今信息系统的体系作战提供了更加有利的支持.当今时代如果爆发战争的话,那么信息则是战争过程中最有利的依据,那么对于无人机的需求呈现出了爆发式的增长.那么本文将主要对体系作战中无人机系统频谱管理研究展开相应的论述.     

不确定环境下的侦察无人机自主航路规划仿真

自主式无人机是无人机发展的必然趋势,不确定环境下的航路规划是无人机航路规划研究的新领域.为了研究战时条件下侦察无人机的自主航路规划,根据无人机的控制系统工作方式,建立了仿真模型框架,并在此基础上开展仿真研究.首先,针对战时条件下侦察无人机执行任务的不确定环境,从战场使用的实际情况出发,建立了基于目标存在概率的环境信息模型;然后,根据无人机机载探测设备探测区域建立了探测模型,提出了航路控制决策模型,并采用动态规划进行航路规划.最后,设计了一个无人机侦察不确定环境的仿真试验,仿真结果验证了该方法的有效性.     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.     

Curved crystal spectrometer for the measurement of X-ray lines from laser-produced plasmas

In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal （200） （2d = 0.4027 nm） is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line（w）, the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line（x）, the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines（y）, the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line（z） in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line（q） in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution（λ/△ 2） is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.     

Electronic Structure of Semiconductor Nanocrystals

This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.     

Critical Stage Rule-Based Real Time Dispatch（RTD）System in Highly-Mixed-Products （HMP） FAB

An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.     

GaAsSb/InAlAs PA DHBTs Grown by Production MBE

The epi material growth of GaAsSb based DHBTs with InAlAs emitters are investigated using a 4 × 100mm multi-wafer production Riber 49 MBE reactor fully equipped with real-time in-situ sensors including an absorption band edge spectroscope and an optical-based flux monitor. The state-of-the-art hole mobilities are obtained from 100nm thick carbon-doped GaAsSb. A Sb composition variation of less than ± 0.1 atomic percent across a 4 × 100mm platen configuration has been achieved. The large area InAlAs/GaAsSb/InP DHBT device demonstrates excellent DC characteristics,such as BVCEO＞6V and a DC current gain of 45 at 1kA/cm2 for an emitter size of 50μm × 50μm. The devices have a 40nm thick GaAsSb base with p-doping of 4. 5 × 1019cm-3 . Devices with an emitter size of 4μm × 30μm have a current gain variation less than 2% across the fully processed 100mm wafer. ft and fmax are over 50GHz,with a power efficiency of 50% ,which are comparable to standard power GaAs HBT results. These results demonstrate the potential application of GaAsSb/InP DHBT for power amplifiers and the feasibility of multi-wafer MBE for mass production of GaAsSb-based HBTs.     

Technology innovation and process integrations for sub-100nm gate patterning

This paper presents a brief overview of the Applied Centura(R)DPS(R)system,configured with silicon etch DPS Ⅱ chamber, with emphasis on discussing tuning capability for CD uniformity control. It also presents the studies of etch process chemistry and film integration impact for an overall successful gate patterning development. Discussions will focus on resolutions to key issues, such as CD uniformity, line-edge roughness, and multilayer film etching integration.     

White organic light-emitting devices based on fac tris（2- phenylpyridine） iridium sensitized 5,6,11,12-tetraphenylnap -hthacene

We have fabricated the white organic light-emitting devices （WOLEDs） based on 4,4＇ -bis（2,2 -diphenyl vinyl）-1,1＇ - biphenyl （DPVBi） and phosphorescence sensitized 5,6,11,12,-tetraphenylnaphthacene （rubrene）. The device structure is ITO/2T-NATA （20 nm）/NPBX （20 nm）/CBP： x%Ir（ppy）3：0.5% rubrene （8 nm）/NPBX （5 nm）/DPVBi （30 nm）/Alq（30 nm）/LiF（0.5 nm）/A1. In the devices, DPVBi acts as a blue light-emitting layer, the rubrene is sensitized by a phosphorescent material, fac tris （2-phenylpyridine） iridium [Ir（ppy）3], acts as a yellow light-emitting layer, and N,N＇ -bis- （1-naphthyl）- N,N＇ -diphenyl -1, 1＇ -biphenyl-4,4＇ -diamine （NPBX） acts as a hole transporting and exciton blocker layer, respectively. When the concentration of Ir （PPY）3 is 6wt%, the maximum luminance is 24960 cd/m^2 at an applied voltage of 15 V, and the maximum luminous efficiency is 5.17 cd/A at an applied voltage of 8 V.     

Complete approach to automatic identification and subpixel center location for ellipse feature

To meet the need of automatic image features extraction with high precision in visual inspection, a complete approach to automatic identification and sub-pixel center location for similar-ellipse feature is proposed. In the method, the feature area is identified automatically based on the edge attribute, and the sub-pixel center location is accomplished with the leastsquare algorithm. It shows that the method is valid, practical, and has high precision by experiment. Meanwhile this method can meet the need of instrumentation of visual inspection because of easy realization and without man-machine interaction.     

小角度扩展相关性近似算法分析

本论文提出一种在多天线MIMO信道相关性建模中小角度扩展近似理论算法,并应用于分析MIMO系统性能。分析中分别对三种不同角能量分布情况下的空间相关性研发快速近似计算法,并同时提出双模(Bi-Modal)角能量分布情况下的近似运算。通过分析这些新方法的近似效率,可以得到计算简单、复杂度低、而且符合实际的MIMO相关信道矩阵,对系统级的快速高效计算法的研究和系统级的评估以及误差分析具有重要的意义。     

Noise character analysis and the restraint of self-pulsation laser diodes

We calculate the Langevin noise sources of self-pulsation laser diodes, analyze the effects of active region noise and saturable-absorption region noise on the power fluctuation as well as period fluctuation, and propose a novel method to restrain the noise effects. A visible SIMULINK model is established to simulate the system, The results indicate that the effects of noise in absorption region can be ignored; that with the increase of DC injecting current, the noise effects enhance power jitter, and nevertheless, the period jitter is decreased; and that with external sinusoidal current modulating the self-pulsation laser diode, the noise-induced power jitter and period jitter can be suppressed greatly. This work is valuable for clock recovery in all-optical network.