共查询到20条相似文献,搜索用时 953 毫秒
1.
2.
3.
4.
自适应阵列天线中的数字波束赋形(DBF)技术是智能天线数字信号处理部分的核心.提出了一种可用于自适应阵列波束赋形的SMI-LMS算法--由SMI(采样协方差矩阵求逆)算法决定LMS(最小均方)算法的初始权向量.该算法充分结合了SMI算法收敛速度快和LMS算法稳态误差小的优点,能在较强干扰环境下,确保权向量的快速收敛和跟踪速度.与传统的LMS算法相比,SMI-LMS算法具有良好的收敛性能、较快的跟踪速度和较小的输出误差,并可以有效改善自适应方向图的副瓣性能.仿真结果验证了该结论. 相似文献
5.
6.
7.
8.
针对恶劣环境中电台话音质量差这一难题,提出了一种有效的解决方法。首先在最小值控制的递归平均Ⅱ型(MCRA-2)算法基础上,提出了一种改进的MCRA-2算法。该算法采用自适应平滑参数和双检测门限,能有效减小音乐噪声,提高噪声估计准确性;然后将该噪声估计算法与对数最小均方误差估计器相结合,实现话音降噪,提高恶劣环境下电台话音质量;最后利用噪声估计结果和降噪后的话音信号,采用信噪比判决算法,自适应估计静噪门限,实现自适应静噪,进一步提高话音舒适度。实验表明,采用该方法的电台在大噪声、强干扰等恶劣环境中使用时,能明显改善话音质量,有效减轻收听者听觉疲劳。 相似文献
9.
针对多用户特征模式传输(MET)算法这种典型的多用户多入多出(MIMO)算法,现实系统中实现时有两个重要限制:其一要求发射端的和功率约束;其二假定噪声、邻区干扰功率项在基站侧已知且将其建模为加性高斯白噪声(AWGN)。在现实系统中,一方面最好遵循每天线发射最大功率的限制,另一方面需要考虑对噪声、邻区干扰功率项的建模,以期望在基站侧更好模拟用户设备(UE)端最终真实感受到的噪声与干扰功率。基于此,提出了一种鲁棒的针对LTE-A的下行多用户MIMO技术,即自适应的切换波束赋形权值归一化算法。同时,基于该归一化的波束赋形权值,提出一种UE级的信干噪比(SINR)补偿机制。使用该补偿的UE级的SINRs,一方面可基于如容量最大等准则,挑选获得给定调度资源上的最优多用户配对集;另一方面,针对该最终配对的多用户集,使用每UE的补偿SINRs做链路自适应,即MCS选择,从而期望获得系统整体和吞吐量的提升。最后,给定仿真参数,链路级仿真结果验证了所设计算法的有效性。 相似文献
10.
本文论述了自适应控制技术在并条机自调匀整系统中的应用问题。介绍了采用单输入单输出的广义最小二乘法来辨识系统,得到系统的CARMA模型的原理和方法;介绍了最了小方差自适应调节器的设计步骤及计算机仿真的方法。 相似文献
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.
《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
19.
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
20.
Guo yan 《中国对外贸易(英文版)》2008,(5):30-31
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, 相似文献