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介绍了AD9858在超短波无线电通信领域中的一种应用.基于AD9858设计一种频率合成器,该频率合成器采用"DDS 倍频"的方案,具有相噪低、跳速快等优点,可用于超短波无线电通信系统. 相似文献
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针对应用于复杂空间环境的宽带接收机的需求,提出了一种新颖的频率源设计方案
。采用锁相环(PLL)和倍频电路实现宽带频综,采用直接数字频率合成器(DDS)实现窄带
细步进频综。给出了频率源的详细设计思路、实现方法及可靠性设计的相关内容,实测
结果表明所设计的频率源各项指标均满足要求。 相似文献
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本文介绍了直接数字频率合成器(DDS)的工作原理和System View的应用,并使用SystemView建立了DDS的仿真系统,得到了相位截断对DDS的影响的仿真结果,对研究和设计DDS系统有着实际意义。 相似文献
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本文介绍了DDS PLL系统的实现方案和特点,指出了设计DDS PLL系统的注意事项,并通过实例证明DDS PLL系统能够实现较高的频谱质量,具有一定的实用价值。 相似文献
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利用matlab仿真工具建立数字频率合成器DDS的仿真模型,便于我们直截了当地了解DDS的工作原理和各部分模块的功能,而且便于我们分析DDS的工作性能和各种参数指标。 相似文献
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为了使直接数字频率合成器(DDS)的IP设计达到资源和效率的较好平衡,提高此类IP设计的灵活性和重用性,应用泰勒插值方法对ROM进行压缩,设计并实现了一种自动生成正交DDS软核的编译器。文中推导了正交DDS内部信号关键参数设定公式,描述了IP编译器的设计流程,给出了实验结果。 相似文献
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《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
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Guo Yan 《中国对外贸易(英文版)》2008,(5)
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. 相似文献
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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
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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
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《中国对外贸易(英文版)》2008,(5):12
The annual meeting of the World Economy Forum was held in Davos,a little town in Switzerland,on January 23rd to the 27th this year,with the theme"the Power fo Collaborative Innovation",over 2500 celebrates from ture political and cconomic circles of more than 80 countries and challengred logether to talk about the future of the global economy in 2008,A Forum for the problems and challenges that face whole world,some of the keywords which drew attention during the event were:the U.S.subprime mortgage crisis,soaring energy prices,the economic slowdown in the U.S.ermerging economic bodies,authority funds and the general unpredictable nature of the global economy. 相似文献
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"If you are considering to trade with companies in Japan or expanding your business to Japan we are ready to help from the very beginning."You will find this greeting at the first sight on the Chinese website of Japan External Trade Organization 《中国对外贸易(英文版)》2008,(10):16-17
If you are considering to trade with companies in Japan or expanding your .business to Japan, we are ready to help from the very beginning." You will find this greeting at the first sight on the Chinese website of Japan External Trade Organization (JETRO). JETRO has committed itself in delivering highly efficient and quality services to meet the demand of internal and external customs including Japanese companies, hence winning a good reputation in the international trade arena. In recent years, with its priority in advancing business cooperation in South and East Asia, JETRO has made great achievement in promoting trade between China and Japan. Therefore, China's Foreign Trade interviewed Mr. Yoichi Maine, Deputy Director General of JETRO BEIJING. 相似文献
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Guo Yan 《中国对外贸易(英文版)》2008,(12):62-63
Looking at the increasingly fierce competition in the world auto market. global automobile manufacturing industry, taking Europe, the U.S. and Japan as representatives, is gradually forming a new type of relationship, mutual cooperation between whole vehicle and parts manufacturers. We can clearly see that auto parts manufacturers have become independent from the whole vehicle manufacturing companies, which means that the former structure of auto industry has greatly changed, and a new relationship, 相似文献
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Estaing, former French president, Valery Giscard d'Estaing attended Sino-French Economic Seminar held in Shanghai in early April and said that the world center has shifted from the west to the east with many European and US companies entering into Asia, and China has the ability to play an important role in the world stage. Estaing, naming himself"French Confucian", then said in Chinese that a cook-group includes 10 people in ancient Chinese soldier system and the cook is in charge of cooking for them. And people who belong to the same cook are actually "Partners". 相似文献
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Guo Yan 《中国对外贸易(英文版)》2008,(1):10-10
In the middle of last December, the key purchase contracts for coal used in power generation in 2008 were signed, reflecting a demand for more than 1.085 billion tons. It is important to note that the country's five biggest power producers, China Huaneng Group, China Guodian Corporation, China Power Investment Corporation, China Huadian Corporation and China Datang Corporation, had settled on the prices on their purchase contracts, and they are expected to consume 290 million tons of coal for generating electricity, 相似文献
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The results of the Annual Global Public Opinion Survey were released by the British Broadcasting Company 《中国对外贸易(英文版)》2008,(9):40-41
The results of the Annual Global Public Opinion Survey were released by the British Broadcasting Company (BBC) on April 2,2008,the combination of 7,457 public opinion polls in 34 countries,gave Germany and Japan the No.1 and No.2 spots,respectively, while the last four went to North Korea, Pakistan,Israel,Iran. 相似文献