一种高精度的BDS/INS紧耦合测姿算法

针对“北斗”卫星姿态测量系统在测姿过程中测姿精度和稳定性不高的问题，提出了“北斗”卫星导航系统（BDS）/惯性导航系统（INS）紧耦合姿态测量算法。该算法首先利用BDS观测量设计了BDS系统测姿误差模型；然后以INS状态误差方程为滤波系统状态方程，以载波相位为主要观测量设计了扩展卡尔曼滤波器，利用滤波器的输出实现对惯性导航测姿系统的辅助校正；最后采用静态测试、动态测试和遮挡测试验证该算法。该系统可以有效提高BDS测姿精度与输出频率，并且在静态条件下航向角测量精度可以达到0.15°。     

基于MLE算法的海上角度交会测量方法及其精度分析

针对我国现有测量船单站REA测量体制精度相对较低的问题,提出了基于光电经纬仪 的海上角度交会测量方法。介绍了角度交会测量原理和设备布站原则,构建了AE-AE异面交 会测量系统,设计了基于MLE（Maximum Likelihood Estimation）算法的海上角度交会测量 算 法和船摇修正方法,仿真分析了船体姿态测量误差、设备测角误差以及站址定位误差等的影 响。仿真结果表明,站址测量误差是海上角度交会测量的最主要误差源,船体姿态测量误差 和设备测角误差对海上角度交会测量精度有一定的影响,当船体水平姿态测量误差优于20″ 、航向测量误差优于30″、设备测角误差优于20″、站址测量误差优于1 m时,海上角 度交会测量精度可达1 m。该法解决了动态条件下的飞行目标高精度测量技术难题,为 后续工程设计奠定了基础。     

基于开关扩展卡尔曼滤波的姿态估计

针对低成本动中通系统中的姿态估计问题,提出一种开关扩展卡尔曼滤波算法。以 无航向角的姿态更新算法为基础,根据微机械陀螺和加速度计分别建立系统状态方程和测量 方程。针对机动加速度的影响,设计了三维开关扩展卡尔曼滤波方程,对载体姿态角和陀螺 零偏进行实时估计。实验结果表明,该算法能够准确估计载体姿态和陀螺零偏,姿态角估计 误差小于0.5°,俯仰角和横滚角估计误差的方差分别为0.130 1°和0.140 5°, 两轴陀螺零偏误差均值均小于(2×10-4) °/s,能够满足动中通的应用要求。     

大风浪作业条件下船舶姿态基准对准系统研究

海上船舶作业条件复杂,对船舶设备和观测系统的精度及可靠性要求也越来越高,尤其是在大风浪作业条件下需要为这些设备提供可靠的船体姿态基准信息.怎样保证姿态基准的可靠性是目前行业尤为关注的问题.因此,提出大风浪作业条件下船舶姿态基准对准系统,研究大风浪作业条件下影响船舶主姿态基准与局部姿态基准之间固态变形角误差估计精度的主要因素,并将这些因素作为状态向量,研究大风浪作业条件下基于惯性测量的卡尔曼滤波器模型,最后通过仿真实验、测试,得出有效性结论.     

综合孔径辐射成像系统的轨道摄动误差修正

为了提高综合孔径辐射成像系统在地球物理摄动因素影响下的图像精度，对低轨星载综合孔径辐射成像系统的成像误差的修正方法进行了研究，提出了针对地球形状摄动、大气阻力摄动以及两种摄动共同作用的空域补偿动力学模型，结合空域摄动法和数值分析方法对这一空域误差补偿动力学模型进行了模型简化以及误差补偿算法的研究，并给出了空域补偿算法的流程图。仿真结果表明，所提出的空域补偿算法极大地提高了综合孔径辐射成像系统对于目标场景物体的恢复精度，有效降低了综合孔径辐射成像系统成像的摄动力误差。     

一种基于TDOA的多天线联合测角算法

针对分布式多天线系统中传统测角方法存在测量精度偏低、宽带信号不适用等问题，提出了一种基于时延差（Time Difference of Arrival,TDOA）测量的多天线二维测角算法。该算法基于最小二乘原理，综合利用多基线测量结果进行迭代计算，有效提高了估计精度，且无需解模糊。推导了算法的克拉美罗界(Cramér-Rao Lower Bound，CRLB)与均方根误差表达式，讨论了算法的测角性能。当天线数为7、天线间距100 m、时延估计精度优于10 μs时，测角精度接近CRLB，方位角精度优于3°，俯仰角精度优于4°。算法复杂度适中，能够应用到多天线无源侦察、空间目标跟踪等应用中。     

基于递推最小二乘算法的惯导姿态误差动态标定方法

在分析最小二乘算法原理的基础上,提出了一种基于递推最小二乘算法的惯导姿态误 差动态标定方法,建立了计算模型,进行了仿真分析。仿真结果表明,该方法具有较高的解 算精度和计算效率,航向误差解算精度优于35″,水平误差解算精度优于015″。该方 法解决了动态条件下惯导姿态误差实时标定的技术难题,对提高惯导姿态测量精度和测 量船外测精度具有重要意义。     

分布式测量体制下的船姿数据重构

新一代航天测量船采用的分布式船姿船位测量体制提高了数据的准确性和可靠性，同时也给数据处理与使用提出了更多的需求，比如姿态数据一致性检验、姿态数据联合使用等。为此，提出了一种新的船姿数据重构方法。首先，对集中式与分布式测量机制进行了对比，分析了采用传统数据处理方法解决新需求会产生困难的原因，并指出姿态重构数据的取得将成为解决这些问题的关键；然后，分两个过程对分布式船体姿态测量数据的重构方法进行了推演，并说明了如何使用重构数据去解决新需求；最后，在重构数据本身精度和重构数据对飞行器目标定位精度影响两个方面对该重构方法进行了检验，结果表明使用该方法得到姿态数据满足任务精度指标要求。     

基于历史信息的雷达测量精度等效评估方法

飞行器发射试验前需要评估测量设备的精度。针对无校飞实验条件下的雷达测量精度评估问题，提出了一种等效精度评估方法，利用历次试验的测量数据和试验前的测试数据评估参试雷达的测量精度。分析了雷达的测量信号流程，建立了检测信息、测试信息到测量精度映射的因子合成回归模型，给出了历次测试信息一致性的秩和非参数检验方法，在测试信息一致的前提下等效评估当前的测量精度。经飞行试验测量数据验证，所提方法对雷达的测量精度评估结果与实际精度的符合性较好，可用于无校飞试验条件下技术状态稳定的雷达精度评估。     

“北斗”信号重构的导向矢量实时校正

针对导航应用中阵列天线导向矢量误差导致波束合成器性能恶化甚至失效的问题，提出了一种“北斗”信号重构的导向矢量实时校正算法。该算法利用重构的本地“北斗”参考信号与阵列天线接收信号进行相关解扩处理，然后利用信号子空间与信号正交补空间正交的特性，构造代价函数对各卫星方向的阵列导向矢量进行校正。仿真结果表明，经过校正的导向矢量相位误差从-100°~100°降低到-10°~10°范围内，幅度误差从-10~10 dB降低到-4~2 dB范围内；另外，导向矢量校正后，卫星信号波达方向估计误差在0.2°以内，估计精度大大提高。     

Public Financial Expenditure——A Reflection of the Livelihood Improvement

In recent years.China's public finance put social construction high on the agenda and attaches more importance on livelihood insurance and improvement.The 2003-2007 public financial expenditure reflects a fact that the government isputting more emphasis on livelihood andissues concerning the people.     

Voices from the MPC and CPPCC

"Crucial for economic growth.energy utilization has its role in all economic sectors and every aspect of people's daily life.Now we are in dire need of a new profession,namely energy manager.We not only need to have passion and responsibility,but also a scientific approach to conserve energy and cut emissions.APpropriate legislation should be in place.and a special profession should be introduced to ensure the implementation of these laws and regulations."     

Slowdown Trade Surplus Growth

According to Ma Kai＇s economic planning report submitted to the NPC session on March 5th,（Ma Kai is the Minister in charge of the National Development and Reform Commission）,the government has listed the slowdown in trade surplus growth and the steady expansion of external investment as major tasks for 2008.     

Ouyang Riping： A Hero Besides Entrepreneur

A bout fifty years ago. a baby＇s cry broke the sky of quietness, in a small and beautiful town of Hunan province, which surroundcd by green hills and clear water. Though his .birth brought his family great happiness and hope just as any new life, nobody knew that the little boy would get great achievement when he grow up. even start his business oversea, and earn international honor. Let＇s share with you the entrepreneur Ouyang Riping＇s story, which may insights thcsc people who want to succeed and complete oneself in favorite condition or adversity rather leave things to so-called fate.     

Belarus, A Chinese Fort in Europe

＂In recent years, we＇ve found increasing interest from Chinese investors in the Belarus economy. Please let China know, Belarus is always ready to be a true friend to China. We have built a fort in Europe for China,＂ the President of Belarus, Alexander Lukashenko told Zhou Xiaochuan, President of the Bank of China, during his visit to the capital of Minsk, on January 8th, he expressed his high praise and firm confidence in the development of Sino-Belarusian relations.     

What＇s Behind Spring Festival？

Similar to what the Christmas Day means for the westerners,the Spring Festival is the most important celebration for Chinese people.This big event according to Chinese traditional lunar calendar relaxes and pleases the whole country as the happiest gathering time of the year.National-wide crusade for going back home,too-difficult-to-get train tickets,generous family-going-out shopping,Miaohui laundering,New Year Eve reunion dinner,visiting friends and relatives,watching annual TV gala......each piece of clue reminds us of the smell of Chinese Spring Festival.     

KEY WDRDS for Foreign Investment in China

FDI(Foreign Direct Investment),a component of a country's national financlal accounts,is investment of foreign assets into domestic structures,equipment,and organizations.It does not include foreign investment into the stock markets,concession and subcontract.FDI iS thought to be more useful to a country than investments in the equity of its companies because equity investments are potentially "hot money"which can leave at the first sign of trouble,whereas FDI is durable and generally useful whether things go well or badly.     

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.     

Consumption, New Protagonist in 2007 GDP

Not long ago, the National Bureau of Statistics released its 2007 Macro Economy Index. Social consumption retail sales reached RMB 8.9 billion, increased by 16.8 percent over the previous year, or 3.1 percentage points higher; the whole investment in social fixed assets was valued RMB 13.7 billion, a year-on-year increase of 24.8 percent, that is 0.9 percentage points higher; and trade surplus amounted to RMB 24.7 billion, rising by 47.7 percent compared with the same period last year, 26.3 percentage points falling over the increasing speed last year. According to preliminary estimates, GDP for the year was RMB 24.67 trillion, up by 11.4 percent from the previous year,