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1.
采用距离和信息的多基地雷达多目标投影定位算法中,距离向脉冲压缩后分辨率降低,需要已知空间中目标个数。针对此问题,提出了一种稀疏重建的多基地雷达多目标定位方法。该方法利用多个接收机中目标稀疏度相同的特点,通过构造平均重构残余误差变化率和平均散射系数变化率作为正交匹配追踪(OMP)算法迭代终止判定条件,自适应地终止OMP算法的同时获得稀疏重建信号以及信号稀疏度的估计值,提高了距离向分辨率,获得了对空间中目标个数的估计。仿真实验表明所提算法有效抑制了距离向主瓣展宽和旁瓣串扰,提高了距离向分辨率。同时,所提算法在不同噪声环境下能准确估计空间中目标个数并提取其空间位置,实现对空间中目标的准确定位。 相似文献
2.
针对高分辨雷达在跟踪扩展目标时出现多散射点的问题,提出了一种基于联合概率加权的雷达目标点迹处理方法。首先,对信号检测出的多散射点构建其残差变量,根据判别准则进行目标点迹配对处理,剔除异常散射点;然后,同时考虑散射点位置和回波幅度信息,计算联合概率的权值,目标多散射点经概率加权融合后估计得到散射中心。仿真分析表明,该方法在高分辨雷达扩展目标点迹处理中能有效抑制杂波的干扰,目标点迹精度在距离、方位和俯仰上分别提高了20.63%、47.51%和41.03%,同时具有很好的可靠性,满足工程应用的需求。 相似文献
3.
为了提高雷达对微弱目标的检测能力,提出了一种多帧相参积累的检测前跟踪(TB
D)方法。通过对多帧时间内运动目标回波的分析,建立了相参积累的回波信号模型,其中
目标回波出现距离单元走动和多普勒单元走动。利用目标回波的空-时相关性,采用速度匹
配法和离散Chirp-Fourier变换(DCFT)联合估计目标径向速度、多普勒频率和调频斜率,
补偿距离单元走动和多普勒单元走动,实现多帧时间内目标能量的相参积累。最后,采用仿
真实验验证了信号模型的正确性和算法的有效性。 相似文献
4.
介绍了频率步进雷达信号实现距离高分辨的工作原理。针对采用步进频信号的某W频
段末制导雷达在系统调试过程中,由于频率源本振和激励源不同频点的相位差不同造成距离
像畸变的情况,分析了信号相位变化对高分辨距离像的影响,根据步进频信号距离高分辨的
原理,提出一种对各频点间相位差进行相位补偿的方法。计算机仿真结果表明
其可行性,并在试验中对该方法进行了验证。通过该方法可以不用对步进频信号各频点的相
参性过高要求,即可得到高分辨距离像,达到理想的距离分辨率,有效降低了W频段频率源
设计和调试的难度。 相似文献
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6.
为了解决临近空间高动态目标的角度引导捕获问题,提出了基于多波束抛物面天线
的高动态目标角捕获方法与基于质心求解的目标指向成像技术。对于系统检测概率、检测时
间进行了理论分析与仿真验证,指出理论分析结果与实际系统存在不一致性。搭建了简化的
中频测试平台,对不同信号形式进行了测角成功概率的测试,为遥外测综合测控自跟踪系统
的建设提供了技术支撑。 相似文献
7.
在一??个三节点多输入单输出(Multi-Input Single-Output,MISO)窃听系统中,当窃听方在信道估计阶段发送恶意导频信号来干扰信道估计时,合法通信的保密性受到严重威胁。针对该安全问题,提出了基于估计信道协方差和基于接收信干比两种恶意导频干扰检测方案。首先概述基于估计信道协方差的恶意导频干扰检测方案原理,推导该方案下检测概率和虚警概率的解析表达式;其次给出基于接收信干比的恶意导频干扰检测方案机制及其检测概率和虚警概率的具体表达式,并通过理论分析对比得出基于估计信道协方差的检测方案性能较优;最后通过数值仿真对比分析了两种方案的干扰检测性能。 相似文献
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9.
本文介绍一种高距离分辨雷达的单个距离单元检测与累积连续的距离单元检测的比较。使用10个具有不同的目标散射特性的目标模型,采用模拟来产生两种检测方法的检测概率曲线。发现累积距离单元检测方法,除由单个强的闪烁点(flare point)组成的目标之外,在各种情况下都是处于较好的情况。 相似文献
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11.
Chun Yi 《中国对外贸易(英文版)》2008,(6)
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. 相似文献
12.
《中国对外贸易(英文版)》2008,(6)
"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." 相似文献
13.
According to Ma Kai's economic planning report submitted to the NPC session on March th. 《中国对外贸易(英文版)》2008,(6):15-15
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. 相似文献
14.
《中国对外贸易(英文版)》2008,(1):64-67
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. 相似文献
15.
Liu Xinwen 《中国对外贸易(英文版)》2008,(5):44-45
"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. 相似文献
16.
《中国对外贸易(英文版)》2008,(5):34-35
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. 相似文献
17.
《中国对外贸易(英文版)》2008,(5):21
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. 相似文献
18.
Holding percent of train media resources across China based on "Time Cube" on the Intermedia Recommendation Introduction Meeting on December HTC announced its high-profile strategy of tour marketing 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 Olympic Games.…… 《中国对外贸易(英文版)》2008,(1):58
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. 相似文献
19.
Audrey Guo 《中国对外贸易(英文版)》2008,(1)
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. 相似文献
20.
《中国对外贸易(英文版)》2008,(5):50-51
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. 相似文献