大气层结构与再入飞行器黑障现象简介

简单介绍了地球大气层的结构;简单介绍了再入飞行器解黑障问题现象、机理以及一些减缓或克服黑障问题的的方法。     

空天飞机的测控通信技术

详细描述了“黑障”产生的原因、对电波传播的影响、等离子体电特性参数；作为一次练习。估算了测控通信系统的工作频率、电波穿过“黑障”区的衰减常数；讨论了空天飞机测控通信体制、主要的系统功能和关键技术。     

《电讯技术》专题资料《近空间飞行器测控与信息传输技术》题要（一）

临近空间飞行器测控系统频段选择（柴霖）测控与信息传输是临近空间飞行器信息保障的核心，而选择合理、可行的频段是展开系统设计的前提和基础。频段选择影响到整个技术方案的制定，是一个需综合考虑、影响深远、具有战略意义的关键问题，本文从ITU（国际电联）法规、高速数传、接收信噪比、“三抗”、超视距中继、黑障、雨衰、     

高超声速飞行器等离子鞘套反演分析

目前等离子体鞘套机理研究主要工作集中在理论模型的分析及地面模拟试验上,缺少真实试验数据的有效支撑,尤其缺少一套系统的试验数据分析方法。通过对等离子体鞘套无线通信试验数据进行数据反演分析,可以获得等离子体鞘套对不同频段无线信号的影响规律,并对等离子体鞘套仿真预测中涉及的流场、烧蚀、电磁计算等模型进行修正。等离子体数据反演分析方案中涉及到高精度链路计算、电子密度测量、飞行器外表面材料烧蚀碳化效应分析以及动态等离子体鞘套电磁分析建模等几项关键技术,通过对其分别进行技术突破,可提高等离子体数据反演分析的精度,使真实数据更为有效地修正理论分析模型。     

码分多址测控系统的功率调节

远近效应是码分多址测控系统中影响飞行器多址接收性能的重要因素。分析了远 近效应在多站测控系统中对飞行器接收性能的影响,提出了在该系统中进行功率控制的必要 性,给出了地面测控站功率调节的方法和策略,可作为多站应用的码分多址测控系统功率调 节的参考思路。     

扩频测控信号抗干扰性能评价方法研究

在分析有源干扰机理和扩频测控信号处理原理的基础上,提出以基于模糊图的有效 面积和一定高度下切割面积评价扩频测控信号固有抗干扰性能的方法。模糊图的有效面积和 切割面积越小,则扩频测控信号的固有抗干扰性能越强。仿真示例表明,所提面积指标均可 有效反映信号固有抗干扰性能。该方法具有可计算性,可为扩频测控信号的抗干扰性能评价 提供方法依据。     

再论发展Ka频段测控通信网的思考

讨论了Ka频段地球网测控通信的特点和主要技术问题,指出了它在高速数传、抗干扰、提高作用距离、提高测量精度、减小"黑障"影响、兼容Ka频段卫通等方面的优点,提出了用虚拟测控系统解决雨衰,用空间谱分析解决Ka频段窄波束捕获等的方案设想.     

运载火箭喷焰的等离子区对信号传输的影响

本文叙述了在传输介质中存在火箭喷焰等离子区引起地面站与火箭之间传输干扰特性的理论和实验结果。其目的是提供有关等离子区对传输影响的定量数据,这对于设计宇宙遥控遥测设备和通讯系统是相当重要的。讨论了基本的传输影响。包括多径散射、前向散射和后向散射,给出并叙述了重要的全部信号传输参数的定义。在叙述和讨论了从“土星”试验系列得到的典型测量结果之后,对信道特性作了概括的讨论。着重讨论了喷焰等离子区对信号传输的三种主要影响,这就是:接收信号电平大幅度下降的可能性,时(间离变散)多径引起的相干带宽的严重減少,以及非常高的衰落速度。讨论了这些影响对运载火箭终端或中继飞行器的信号设计和解调的关系。     

船载测控雷达空间目标轨迹仿真生成方法

提出几种典型飞行器轨迹的仿真方法,在分析各种坐标系及相互关系的基础上,给出了船姿、船位、变形模拟数据的计算方法以及船载测控雷达空间目标轨迹的动态仿真生成方法,为船载测控雷达操作手进行仿真训练提供了高度逼真的动态条件.     

混沌扩频测控系统同步捕获性能分析

混沌序列在扩频测控系统中的应用引起了人们的广泛兴趣,混沌扩频测控系统的捕获性能和跟踪性能是学界关注的重点。由于数字化混沌序列相关函数旁瓣具有随机性,使得扩频系统的信号捕获过程,除了受加性噪声影响之外,又增加了一个影响因素。根据系统捕获原理与混沌码特性,借助于混沌码模糊函数的概念,提出了混沌码相关函数旁瓣随机性影响下检测概率、虚警概率以及捕获时间的计算方法,推导得到了相应的计算公式,探讨了混沌扩频测控系统的信号捕获性能。结果表明,混沌码相关函数随机性的存在使检测概率和虚警概率有所增大,并使捕获时间产生变化;与加性噪声相比,其影响通常较小甚至可以忽略。该结果可以为混沌序列在扩频测控系统中的应用提供理论支持与参考。     

Universal Coverage, Pinpoint Illustration and Profound Impact HTC 2008 Intermedia Recommendation and Introduction Meeting

Holding 88 percent of train media resources across China, based on "Time Cube", on the 2008 Intermedia Recommendation and Introduction Meeting on December 19, 2007, HTC announced its high-profile strategy of tour marketing and tapping the immeasurable potentials on the train. Meanwhile, HTC officially launched its brand new product Olympic Train on the meeting, providing a fabulous platform for all the brands that are prepared to do a smart marketing on the occasion of 2008 Olympic Games.     

Market presence in China strengthened Network growth and Dual-Chinese-Hub Strategy More frequet Flyer Benefit——Air China and shanhai Airlines Join Star Alliance

In the end of 2007, Air China Limited (hereinafter "Air China") and Shanghai Airlines, formally joined Star Alliance at a ceremony held in the new Terminal Three at Beijing Capital International Airport. With the addition of the two Chinese airlines, Star Alliance now has 19 member carriers operating 17,000 daily flights to 897 destinations in 160 countries.     

Brown＇s Blossom in Britain-China

The overall strategic relationship between U.K. and China is ＂better than ever＂, China- Britain relations have maintained good momentum, with increased high-level exchanges and the reinforcement of strategic mutual trust, with more room for growth in the future.     

Challenge and Opportunity Go Hand in Hand——What Global Economic Agitation Brings to the China's Economy?

Domino effects of the global finance agitation As the origin of the subprime crisis,US financial institutions lost USS45 billion last year,accounted for over half of the total US,EU & Japan loss.Since January 15th,Chtigroup released its financial statement of the 4th quarter,showing a net deficit of USS9.83 billion,which marked the hisoric high of its quarterly deficit.     

Sinosteel：Extraordinary Moves in Industry Chess

Among the Fortune 500 firms,more and more images from China emerge out.On the 2008 list,Sinosteel Corporation,a landmark group of China industries quietly squeezes into the candidate line.As the largest steel service ＆ trade enterprise,its sales reached at RMB 111.24 billion,with a year-on-year increase of 83.03 percent,and the profit grew by 180.03 percent.On the Sinosteel 2008 Work Meeting,the president Huang Tianwen uttered,＂In the coming year,we will work for US$20 billion sales,and look forward to getting a position in Fortune 500 firms for ourselves.＂     

Walk Through Unusual Five Years—— An Exhibitor＇s Canton Fair Course

When the 103rd Canton Fair is approaching, an old friend of Canton Fair, Li Ying from Jiangsu prov-ince recollected his past five years＇ experiences to the grand trade meeting. Each year is special, with some unforgettable memories colored by the year.     

A World of Love 2008 Music Grand Ceremony

Under the guidance of the theme slogan of the 29th Olympic Games - One World One Dream, with dream, love and dedication as its theme, the 2008 Music Grand Ceremony ＆ 1000 People Charity Concert on 100 days cotmtdown to Paralympic Gamesis officiaily launched on December 22, 2007. The 2008 Music Grand Ceremony is sponsored by China Disabled Persons＇ Federation, and co-hosted by National Paralympic Committee of China,     

China''''s National Oil Reserve Center was Born

Aseries of events that occurred in October 2007, are rewriting the history of China's energy industry: November 3 an Energy Law Committee asked the public for suggestions on improvements; forty top experts came together to form the National Energy Expert Advisory Committee on November 6; and the National Oil Reserve Center (NORC)became the nerve centre of oil reserves on November 18. Yet, behind the progress of these recent activities remains the fact that international oil prices still hover around a very high price of US$ 90/barrel, and China's oil imports are close to accounting for half of its total oil reserves.     

MUYANG GROUP

With its headquarters in the historic city of Yangzhou,Jiangsu Muyang Group Co.,Ltd has since its founding in 1967 grown into a well-known group corporation whose activities cover research ＆ development,project design,manufacturing,installation and services in a multitude of industries including feed machinery and engineering,storage engineering,grain machinery and engineering,environmental protection,conveying equipment and automatic control systems.     

2007 China Harbor Ten People

2007 China Harbor Ten People elected the entrepreneurs who contributed a lot to port economy and enterprises this year trough their talent management.These ten people embody their social responsibility,professional skills,creative ability,and charming personality.Bearing full confidence in China＇s port economy,the port entrepreneurs are brave enough to explore a brand new area,so as to promote harbor economic development. At the very beginning of 2008,China Shipping Website,Dalian Maritime University,and China Port and Shipping In- stitute jointly select the 2007 China Harbor Ten People,demonstrate port entrepreneurs＇ stunning minds,disclose their secrets to success,and providing abundant experiences to others in harbor development.The top ten people are various excellence during the ups and downs harbor development.