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1.
结合Viterbi译码算法和最新的FPGA实现技术,对实现Viterbi译码器的两种常见实现思路进行分析,仿真并采用FPGA对其中的一种进行了终端验证。对两种算法采用Verilog Hdl实现,其中寄存器交换算法实现起来相对简单,对其进行了终端验证;基于存储器管理的算法实现起来相对困难,回溯模块和存储器寻址是实现的难点与焦点,本论文提出了两种存储器的寻址方法,并对其进行了仿真。整个设计采用Verilog HDL实现。  相似文献   

2.
USB数据传输中CRC校验码的并行算法实现   总被引:8,自引:2,他引:6  
文章介绍了用于USB总线数据传输的CRC校验的原理和算法,并且采用并行电路实现USB2.0中的CRC产生和CRC校验,与传统的串行电路实现相比,并行电路实现方法虽然在芯片面积上大于串行电路实现,但由于降低了时钟频率,电路更容易综合实现,并且大大降低了功耗,有利于低功耗电路设计。  相似文献   

3.
郑晓霞 《信息技术》2005,29(7):123-125
介绍了基于LOTUS DOMINO/NOTES文档管理系统的开发过程,该系统真正实现文档办公的工作流程,不仅可以实现纸制文件的归档,而且可以实现电子文档的归档,同时实现了自动组卷、封卷、毁卷、回收、查询和借阅功能,真正提高工作效率,为最终实现无纸化办公奠定基础。  相似文献   

4.
罗忠 《电子技术》2023,(2):362-363
阐述使用虚拟化技术实现远程操作,利用软件技术实现一二次加密,通过文件加密技术实现试卷保密,线上摄像头实现远程监控。  相似文献   

5.
无线传输的保密性和安全性已经成为用户的需求,完整性保护正是基于传输安全而设计提出的,他是第三代移动通信要求实现的基本功能。本文详细介绍了完整性保护在无线通信系统中的应用以及实现的方法。并且基于TD-SCDMA系统以其一般性过程为例,详细介绍了完整性保护实现的具体过程,最后结合实际工作中的成果,重点分析了其算法的实现。其中包括算法实现的设计思想,参数设计,以及算法最终实现的流程图。  相似文献   

6.
基于TD-SCDMA系统的完整性保护算法的研究   总被引:1,自引:0,他引:1  
王冉  李小文 《信息技术》2005,29(10):18-21
无线传输的保密性和安全性已经成为用户的需求,完整性保护正是基于传输安全而设计提出的,他是第三代移动通信要求实现的基本功能。现介绍了完整性保护在无线通信系统中的应用以及实现的方法,并且基于TD—SCDMA系统以其一般性过程为例,还详细介绍了完整性保护实现的具体过程,最后结合实际工作中的成果,重点分析了其算法的实现,其中包括算法实现的设计思想,参数设计,以及算法最终实现的流程图。  相似文献   

7.
Windows网上邻居的主要功能是实现资源的共享,具体的实现方式可通过多种方法来实现,但是实现起来会遇到各种各样的问题,本文所阐述的是实际工作中网上邻居产生问题的原因以及实现的功能。  相似文献   

8.
基于以太网实现VOD的方法研究   总被引:5,自引:4,他引:1  
对基于以太网视频点播(VOD)系统的实现方法进行了研究,综述了VOD的特点、结构及其关键技术,介绍了基于以太网的VOD系统结构,系统实现的主要工作,重点讨论了系统实现的几项关键技术,指出了该系统实现方法的应用范围。  相似文献   

9.
刘桐岳 《电子技术》2023,(3):190-191
阐述基于信息技术的现场勘验设备与技术优化,包括实景重建、永久保留、实现勘验由案查人,海量数据库、实现勘验由人查案,注重信息采集关键环节、实现勘验由案查案,天眼全天候在线,实现勘验查漏补缺。  相似文献   

10.
手机电视技术发展及基于3G的应用探讨   总被引:2,自引:0,他引:2  
王小旭 《通信世界》2005,(45):41-42
目前,手机电视业务的实现方式主要有三种:基于地面广播的实现,基于卫星广播的实现以及基于移动网络的实现。  相似文献   

11.
Improved LUT Technique for HPA Nonlinear Pre-Distortion in OFDM Systems   总被引:3,自引:0,他引:3  
In this paper, we focus on the Look-up Table (LUT) technique for the compensation of HPA nonlinear distortion. An improved LUT method is proposed with better performance compared with conventional LUT technique in terms of convergence speeds, BER and total degradation (TD). It can get over 8 dB gain in out-of-band spectrum re-growth suppression and about 0.3 dB BER performance gain than conventional LUT technique with the same iteration times. Also, we propose an actual application of HPA with pre-distorter in OFDM transmitter. Ai Bo was born in Shannxi Province in China on February 7, 1974. He received a BSc. Degree from Engineering Institute of Armed Police Force in 1997, a Master and Dr. degree from Xidian University in 2002 and 2004 in China respectively, and now working as a post dr. in Dept. of E&E, state of key lab. on microwave and digital communications in Tsinghua University in China. He has once participated in the key research project on HDTV in TEEG (Team of Engineering Expert Group) of China. He is an editorial committee member of journal of “Computer Simulations”, “Information and Electronic Engineering”, an IEEE member and a senior member of Electronics Institute of China (CIE). He has published over 60 scientific papers in his research area till now. His current interests are the research and applications of OFDM techniques with emphasis on synchronization and HPA linearization techniques. Yang Zhi-Xing graduated from Tsinghua University, P.R. China in 1970. He is now a Professor and Deputy Director of State Key Lab. on Microwave and Digital Communication at the Department of Electronic Engineering and the Director of the DTV R&D Center in Tsinghua University. As a DTV technical expert for the Chinese government, Professor Yang has also been a member of the DTV standardization Committee of China and a leader of the DTV Standardization Harmonizing Group in Ministry of Information Industry of China. His major research interests include broadband information transmission technologies and DTV broadcasting systems. Pan Chang-Yong received the B.S. and M.S. degrees from the Department of Electronic Engineering in Tsinghua University, P.R. China, in 1996 and 1999, respectively. He is now an associate professor in the Department of Electronic Engineering and a member of the DTV R&D Center in Tsinghua University. His research interests are in the areas of broadband wireless transmission systems and satellite communications. Zhang Tao-Tao was born in Shandong Province in China in 1982, he received BSc. degree from Tsinghua University in 2004 and now pursing his Master degree in Dept. of E&E, state of key lab. on microwave and digital communications in Tsinghua University in China. His research interests is the power amplifier linearization techniques. Wang Yong was born in Shannxi Province in China in 1976. He received a BSc., a Master and a Dr. Degree from Xidian University in China in 1997, 2002 and 2005, respectively, and now is an associate professor in Xidian University. He has once participated in the key research project on HDTV in TEEG (Team of Engineering Expert Group) in China and is an IEEE Member. His interests are broadband multimedia communications. Ge Jian-Hua was born in September, 1961 in JiangSu Province in China. He received the B.Sc., Master and Ph.D. degree from Xidian University in 1982, 1985 and 1989, respectively. He is now the professor in both Xidian University in Xi’an and Shanghai Jiaotong University in Shanghai. He is the senior member of Chinese Electronics Institute. He has won lots of scientific and technical prizes in China and published many papers. His interests are transmission communications and web security.  相似文献   

12.
An attempt is made to determine if investment in R&D and the hiring of college-educated employees result in a higher rate of inventions. The relationship between the input of R&D and inventive output is studied in two samples of Japanese factories, 34 in 1982 and 44 in 1970. These results are compared with findings in a parallel American study. The correlations between R&D and inventive output are similar in Japan and America in the 1980s, despite some differences in the management of innovation in the two nations. Moreover, the most Westernized subsample of Japanese firms in the 1970s had correlations between R&D and invention similar to those observed in the American study. Thus, it is concluded that some degree of convergence may be taking place in R&D management strategies in the two nations  相似文献   

13.
中国地区云量和云光学厚度的分布与变化趋势   总被引:1,自引:0,他引:1  
利用最新的1983~2009年国际卫星云气候计划(ISCCP) D2月平均资料集,得到了中国地区总云量、低云量、中云量、高云量与云光学厚度的分布与变化趋势,结果表明:中国总云量和中云量呈现南多北少的分布,青藏高原地区高云量较大而低云量很小;总云量和中云量在东部呈增加趋势,西部呈减小趋势,低云量和高云量在大部分地区呈减小趋势。从不同季节来看,春季和秋季北方总云量增加,西部总云量减小;夏季大部分地区总云量增加,冬季大部分地区总云量减少。云的光学厚度呈现南多北少的分布,且在大部分地区呈增加趋势。同时利用中分辨率成像光谱仪(MODIS)资料分析了2001~2013年间中国不同污染地区总云量与云光学厚度的分布及变化趋势的异同,结果表明:中国不同污染地区云量与云光学厚度呈现不同的分布和变化规律。  相似文献   

14.
简季  宋练  谢洪斌  罗真富  谭德军  高波 《红外》2013,34(8):30-34
矿山开采中产生的固体废弃物和废液会使矿区土壤中富集重金属元素,进而影响矿区内的农作物生长。选择重庆市万盛区矿区作为研究区,采集红薯和南瓜的实测高光谱数据和土壤样本的重金属含量数据。通过对土壤重金属含量和农作物的红边位置偏移进行相关分析,发现不同土壤重金属含量对研究区内主要农作物的影响是不同的。可以看出,在研究区内的两种主要农作物中,红薯对矿区土壤中的重金属Cr、Mn和Cd比较敏感,而南瓜则对以上三种土壤重金属具有一定的吸收和抵抗作用。该结果可以为万盛区矿区内农作物种植的选择提供理论依据。  相似文献   

15.
根据无人作战模拟研究、开发过程中分队级作战单位建模与仿真环节上所存在的VV&A问题,从军事建模的过程与军事工程技术的角度出发,将一般仿真过程中的VV&A技术与军事作战模拟的特点以及无人作战模拟的特殊性三者有机的结合在一起,深入的探讨了在无人作战模拟仿真过程中VV&A问题的解决办法以及实现过程。通过对无人作战模拟仿真中VV&A的研究与解决,为今后的作战模拟,特别是无人作战模拟中如何解决建模及仿真过程中所存在的类似问题提出了一套系统的、科学的实现办法,具有一定的理论及实践意义。对于我军无人作战研究的深入开展以及跨越式发展具有一定的参考价值。  相似文献   

16.
吴迪  王瑞 《电波科学学报》2019,34(5):655-662
利用2007-2013年的COSMIC掩星数据,分析了E区与F区电离层闪烁的变化特征.发现用闪烁出现频次、闪烁发生率以及闪烁强度来表征的电离层闪烁出现规律比较相似.E区电离层闪烁在夏季半球的中纬地区最强,其次是春秋季的低纬地区和冬季半球.就经度分布来说,春秋季E区电离层闪烁呈四波结构.对F区电离层闪烁来说:南美-大西洋扇区在12月至点最为显著;非洲和太平洋扇区在6月至点最为显著;大西洋扇区在春秋分季最为显著.极区也出现中等强度的闪烁,尤其在南半球的90°E~180°E扇区较为显著.高纬E区电离层闪烁强度随太阳活动的增强而增强,而低纬和南半球的中纬E区闪烁随太阳活动的增强而减弱.高纬和低纬F区闪烁随太阳活动的增强而增强,而中纬F区电离层闪烁对太阳活动无显著依赖关系.对于赤道区来说,北半球60°W~60°E经度区闪烁强度随太阳活动的变化最为显著,其次是南半球60°E~210°E附近;而对于高纬地区来说,F区闪烁强度随太阳活动的变化最为显著的区域在南半球60°E~210°E附近.  相似文献   

17.
海洋有机碳存量估算对研究碳循环过程和预估气候变化趋势有重要的作用。海洋有机碳存量可以通过遥感反射率、水体光学特性等参数反演得到。根据东海水域的水体特性,对比了多种有机碳反演算法,并结合东海有机碳垂直分布情况,得到一套完整的东海有机碳存量估算模型。利用2010年MODIS提供的遥感反射率数据和Argo提供的温盐数据,对中国东海区域的有机碳储量分季节进行计算分析。结果表明东海全水柱有机碳储量在1.530×1014 g到2.125×1014 g之间,真光层有机碳储量在4.119×1013 g到7.980×1013 g之间。全水柱有机碳储量整体呈现冬季高、春季低的特点,真光层有机碳储量整体呈现夏季高、冬季低的特点。从2006年至2015年,有机碳存量呈波动上升趋势。对东海有机碳存量进行了较为准确的估算,为今后我国海洋碳储量的评估提供了可供参考的思路。  相似文献   

18.
Noise in solid-state devices and lasers   总被引:1,自引:0,他引:1  
A survey is given of the most important noise problems in solid-state devices. Section II discusses shot noise in metal-semiconductor diodes, p-n junctions, and transistors at low injection; noise due to recombination and generation in the junction space-charge region; high-level injection effects; noise in photodiodes, avalanche diodes, and diode particle detectors, and shot noise in the leakage currents in field-effect transistors (FETs). Section III discusses thermal noise and induced gate noise in FETs; generation-recombination noise in FETs and transistors at low temperatures; noise due to recombination centers in the space-charge region(s) of FETs, and noise in space-charge-limited solid-state diodes. Section IV attempts to give a unified account of 1/f noise in solid-state devices in terms of the fluctuating occupancy of traps in the surface oxide; discusses the kinetics of these traps; applies this to flicker noise in junction diodes, transistors, and FETs, and briefly discusses flicker noise in Gunn diodes and burst noise in junction diodes and transistors. Section V discusses shot noise in the light emission of luminescent diodes and lasers, and noise in optical heterodyning. Section VI discusses circuit applications. It deals with the noise figure of negative conductance amplifiers (tunnel diodes and parametric amplifiers), and of FET, transistor, and mixer circuits. In the latter discussion capacitive up-converters, and diode, FET, and transistor mixers are dealt with.  相似文献   

19.
Some empirical results and observations are presented which describe the principal ways in which a sample of industrial researchers in Japan and in the US utilize certain technologies resulting from university research. The findings are from a survey conducted in Japan and the US between October 1986 and December 1987. These results indicate that personal communications and technical collaboration are the key factors in the rapid diffusion of research results in both countries, and that in Japan, government agencies and professional societies take a much more active role in organizing and energizing the civilian technology-transfer process than do counterpart organizations in the US  相似文献   

20.
微视频在学校各类教育中应用越来越普遍.依据微视频的教学特点,针对高校计算机操作性课程中存在的问题,本研究依据ADDIE模型和ARCS动机理论,探索构建微视频在高校计算机操作性课程中的教学应用模型,通过教学案例展示微视频在课堂应用中教与学的过程,利用微视频提高课堂教学质量.  相似文献   

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