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matlab 图像提取中心线
matlab进行图像处理，对图像提取中心线与轮廓，还有二值化等
- 2020-12-06下载
- 积分：1
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Turbo 码MAP 译码算法的研究与仿真
【实例简介】1993 年，法国的C.Berrou 等人提出了一种新的纠错编码方式—Turbo 码，当交织
长度足够长时，其性能接近Shannon 信道编码极限值，因此Turbo 码的出现，被看作是信道
编码理论发展史的一个里程碑，它使人们设计信道编码的方法从增加码的最小汉明距离转向
减少低重量码字的个数。Turbo 码性能优异，已经被确定为第三代通信系统的信道编码方案
之一。本文介绍了Turbo 码的编译码原理及其在TD-SCDMA 通信系统中的应用情况；结合
Turbo 码的迭代译码过程，重点讨论MAP 译码算法的详细推导和具体应用方法；根据
3GPP25.222 协议中定义的Turbo 码标准，从不同角度进行MAP 译码算法的MATLAB 仿真。
根据仿真结果，分析MAP 算法的译码性能，并且就设计参数对译码性能的影响进行了比较
性分析。
- 2021-11-13 00:31:39下载
- 积分：1
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FM的调制与解调的MATLAB仿真程序
FM的调制与解调这是个MATLAB仿真程序，自已认为写的很好！希望会对你有用！！！
- 2020-06-26下载
- 积分：1
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OFDMA System Analysis and Design
OFDMA系统分析与设计的国外经典教材Chapter 1 Introduction to OFDM and OFDMAChapter 2 Characterization of the Mobile Wireless ChannelChapter 3 Fundamentals of Digital Communications and NetworkingChapter 4 Fundamentals of OFDM and OFDMA: Transceiver StructureChapter 5 Physical Layer: Time and FrequencyChapter For a listing of recent titles in theArtech House Mobile Communications Library,turn to the back of this bookOFDMA System Analysis and DesignSamuel C. YangARTECHHOUSEBOSTON LONDONartechhouse. comLibrary of Congress Cataloging-in-Publication DataA catalog record for this book is available from the U.S. Library of CongressBritish Library cataloguing in Publication DataA catalogue record for this book is available from the british libraryISBN-13:978-1-60807-076-3Cover design by vicki KaneC 2010 Artech House685 Canton streetNorwood. MA 02062All rights reserved. Printed and bound in the United States of America. No partof this book may be reproduced or utilized in any form or by any means, elec-tronic or mechanical, including photocopying, recording, or by any informationstorage and retrieval system, without permission in writing from the publisherAll terms mentioned in this book that are known to be trademarks or servicemarks have been appropriately capitalized artech House cannot attest to theaccuracy of this information. Use of a term in this book should not be regardedas affecting the validity of any trademark or service mark10987654321To my beautiful wife JennyContentsPrefaceAcknowledgmentsXVCHAPTER TIntroduction to ofdm and ofdma1.1 Motivation1.2 Conventional FDm1.3 Advantages of FDm1.3.1 Intersymbol Interference(ISI)and Multipath Fading1.3.2 Modulation and Coding per Subcarrier1.3.3 Simple equalization1.4 Disadvantages of FDM1.5 Basics of ofdm1.6 Advantages of OFDM1.6.1 Low-Complexity modulation1.6.2 Spectral Efficiency1.7 Basics of ofdma1.8 Advantages of OFDMA121.9 Some Practical issues of ofdm and ofdma1.9.1 Time Domain: Interblock Interference131.9.2 Frequency Domain: Intercarrier Interference131.10 OFDM and Dsss141.11 Overview of the book14References15Selected BibliographyCHAPTER 2Characterization of the mobile wireless channel2.1 Introduction2.2 Link analysis2.3 Distance Dimension: Propagation Loss2.3.1 Path Loss2.3.2 Shadowing Loss24Contents2.3.3 Multipath Fading26Example 2.1282.3.4 Concluding Remarks292.4 Time Dimension: Multipath Delay Spread302.4.1 Delay Spread30Example 2.231Example 2.3312. 4.2 Coherence bandwidth322.4.3 Implications for OFDM352.5 Frequency Dimension: Doppler Spread362.5.1 Doppler Spread36Example 2. 4372.5.2 Coherence time2.5.3 Implications for OFDM402. 6 Conclusions41References43Selected Bibliography44ChAPTER 3Fundamentals of Digital Communications and Networking453.1 Introduction453.2 Basic Functions of a Transceiver453.3 Channel Coding473.3.1 Linear block codes473.3.2 Convolutional codes493.4 Symbol mapping and modulation3.5 Demodulation563. 5. 1 Matched Filter563.5.2 Symbol Error3.6 Adaptive Modulation and Coding603.7 Cyclic Redundancy Check(CRC)623.8 Automatic Repeat Request(arQ)643.8.1 Stop-and-Wait ARQ643.8.2 Sliding Window arQ653.9 Hybrid ARQ67References69Selected bibliographyCHAPTER 4Fundamentals of ofdm and ofdma: transceiver structure4.1 Basic Transmitter functions714.2 Time domain: guard time4.3 Frequency Domain: Synchronization744.4 Basic receiver functions754.5 Equalization764.6 OFDM Symbol79Contents4.7 OFDMA Transmitter844. 8 OFDMA Receiver4.9 OFDMA4.9.1 Frequency diversity4.9.2 Multiuser diversity914.9.3 Concluding Remarks4.10 Peak-to-Average Power ratio924.11 Conclusions93References94Selected Bibliography95CHAPTER 5Physical Layer: Time and Frequency975.1 Introduction5.2 Distributed Subcarrier Permutation: Forming Subchannels onDownlink5.2.1 Full Usage of Subchannels(FUSC1005.2.2 Partial Usage of Subchannels(PUSC)1015.2.3 Tile Usage of Subchannels 1(TUSC1)1025.2.4 Tile Usage of Subchannels 2(TUSC2)1025.3 Distributed Subcarrier Permutation: Forming Subchannels on Uplink 1025.3.1 Partial Usage of Subchannels(PUSC)1035.3.2 Optional Partial Usage of Subchannels(Optional PUSC)1035.4 Adjacent Subcarrier Permutation: Downlink and Uplink1045.5 Summary of Subcarrier Permutation Modes1045.6 Bursts and Permutation Zones1055.7 Subframes and frames1075.7.1 Preamble1105.7.2 Frame Control Header(FCH)1105.7.3 Downlink MAP (DL-MAP)and Uplink MAP(UL-MAP1115. 8 TDD and FDD5. 9 System Design Issues1125.9.1 Frequency Diversity and multiuser diversity1125.9.2 Segmentation1125. 10 Adaptive burst profiles1155.10.1 Burst Profiles1155.10.2 Channel Quality Feedback116References117ChAPTER 6Physical Layer: Spatial Techniques1196.1 Introduction6.2 Spatial Diversity: Receive Diversity1206.2.1 Receive Diversity: Antenna Selection1226.2.2 Receive Diversity: Maximal Ratio Combining6.3 Spatial Diversity: Transmit Diversity123Contents6.3. 1 Transmit Diversity: Open-Loop 2 X 11246.3.2 Transmit Diversity: Open-Loop 2X 21266.3.3 Transmit Diversity: Closed-Loop Antenna Selection128Example 6.11296.3.4 Transmit Diversity: Closed-Loop precoding1306.3.5 Remarks1326.4 Spatial Multiplexing1336.5 MIMO-OFDM1366.6 Beamforming1366.7 System Design Issues139References140Selected Bibliography141CHAPTER 7Medium Access control: architecture and data plane1437.1 MAC Architecture1437.2 Convergence Sublayer1457. 2.1 Address Mapping( Classification1467. 2.2 Header Suppression1467. 3 Common Part Sublayer1477.3.1ARQ1477. 3.2 MAC SDU and MAc pdu1487.3.3 Fragmentation/Packing1497.4 Security Sublayer152References152chaPTeR 8Medium Access Control Lower Control plane1538. 1 Introduction1538.2 Scheduler1538.3 Bandwidth Request1558.3.1 Request in Existing Uplink Allocation1568.3.2 Unicast Polling1568.3.3 Multicast and Broadcast Polling1578.3.4 Contention-Based Request for OFDMA1578.4 Control Signaling1588.5 Ranging1598.5.1 Initial Ranging1598.5.2 Periodic Ranging1608.5.3 Handover ranging1618.6 Power Control1618.6.1 Uplink Power Control: Closed-Loop1648.6.2 Uplink Power Control: Open-Loop1668.6.3 Assignment of Uplink Modulation and Coding8.6.4 Concluding Remarks168References169ContentsChaPTER 9Medium Access Control: Upper Control plane1719.1 Introduction1719.2 Network Entry1719.2. 1 Synchronization with Downlink of Base Station and acquisitionof parameters1739.2.2 Initial Ranging1739. 2.3 Negotiation of Mobile Capabilities1749.2.4 Security Procedures1749.2.5 Mobile registration1759.2.6 IP Connectivity1759.2.7 Connection Setup1769.3 Mobility Management: Link Handover1769.3.1 Cell Reselection1779.3.2 Hard Handover(HHO1799.3.3 Macro Diversity Handover(MDHO)1849.3.4 Fast Base Station Switching(FBSS1879.3.5 System Design Issue: H Add and h delete1899.3.6 Concluding Remarks1919.4 Mobility management: Network handover192References192CHAPTER 10Quality of Service(Qos)19510.1 Introduction19510.2 Definitions and Fundamental Concepts19510.2.1 Service Flows and Qos Parameters19510.2.2 Connections19610.3 Object Relationship Model19710.4 Service flow transactions19910.4.1 Creating a Service Flow19910.4.2 Changing a Service Flow20010.4.3 Deleting a Service Flow20310.5 QoS Parameters20410.6 Scheduling Services20610.6.1 Unsolicited Grant Service(UGS)20610.6.2 Real-Time Polling Service(rtPS20710.6.3 Extended Real-Time Polling Service(ertPS20710.6.4 Nonreal-Time Polling Service(nrtPS20810.6.5 Best Effort(BE)20810.6.6 Remarks209References210
- 2020-11-30下载
- 积分：1
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SIFT算法详解及应用(讲的非常好很详细)
SIFT算法特点• SIFT特征是图像的局部特征，其对旋转、尺度缩放、亮度变化保持不变性，对视角变化、仿射变换、噪声也保持一定程度的稳定性。• 独特性(Distinctiveness)好，信息量丰富，适用于在海量特征数据库中进行快速、准确的匹配。• 多量性，即使少数的几个物体也可以产生大量SIFT特征向量。• 经过优化的SIFT算法可满足一定的速度需求。• 可扩展性，可以很方便的与其他形式的特征向量进行联合。SIFT简介SIFTScale Invariant Feature Transform传统的特征提取方法成像匹配的核心问题是将同一目标在不同时间、不同分辨率、不同光照、不同位姿情况下所成的像相对应。传统的匹配算法往往是直接提取角点或边缘,对环境的适应能力较差,急需提出一种鲁棒性强、能够适应不同光照、不同位姿等情况下能够有效识别目标的方法。己0]/3/己7彐SIFT简介SIFTScale Invariant Feature TransformSIFT提出的目的和意义分1999年 British columbia大学大卫.劳伊( David g.Lowe)教授总结了现有的基于不变量技术的特征检测方法,并正式提出了一种基于尺度空间的、对图像缩放、旋转甚至仿射变换保持不变性的图像局部特征描述算子一SIFT(尺度不变特征变换),这种算法在2004年被加以完善己0]/3/己7SIFT简介SIFTScale Invariant Feature Transform将一幅图像映射(变换)为一个局部特征向量集;特征向量具有平移、缩放、旋转不变性,同时对光照变化、仿射及投影变换也有一定不变性。己0]/3/己7SIFT简介SIFTScale Invariant Feature TransformSIFT算法特点SIFT特征是图像的局部特征,其对旋转、尺度缩放、亮度变化保持不变性,对视角变化、仿射变换、噪声也保持一定程度的稳定性。独特性( Distinctiveness)好,信息量丰富,适用于在海量特征数据库中进行快速、准确的匹配。多量性,即使少数的几个物体也可以产生大量SIFT特征向量。经过优化的SIFT算法可满足一定的速度需求。可扩展性,可以很方便的与其他形式的特征向量进行联合。己0]/3/己7SIFT简介SIFTScale Invariant Feature TransformSIFT算法可以解决的问题目标的自身状态、场景所处的环境和成像器材的成像特性等因素影响图像配准/目标识别跟踪的性能。而SIFT算法在一定程度上可解决:目标的旋转、缩放、平移(RsT)图像仿射/投影变换(视点 viewpoint)光照影响(111 amination)目标遮挡( occlusion)杂物场景(c1 utter)噪声己0]/3/己7SIFT算法实现细节SIFTScale Invariant Feature TransformSIFT算法实现步骤简述SIFT算法的实质可以归为在不同尺度空间上查找特征点(关键点)的问题。原图像特征点特征点目标的特检测描述征点集特征点匹匹配点矫配正目标图像特征点特征点目标的特检测描述征点集SIFT算法实现物体识别主要有三大工序,1、提取关键点;2、对关键点附加详细的信息(局部特征)也就是所谓的描述器;3、通过两方特征点(附带上特征向量的关键点)的两两比较找出相互匹配的若干对特征点,也就建立了景物间的对应关系。SIFT算法实现细节SIFTScale Invariant Feature TransformSIFT算法实现步骤关键点检测己。关键点描述彐·关键点匹配4·消除错配点己0]/3/己7关键点检测的相关概念SFTiant Feature Transfor1.哪些点是SIFT中要查找的关键点(特征点)?这些点是一些十分突出的点不会因光照条件的改变而消失,比如角点边缘点、暗区域的亮点以及亮区域的暗点,既然两幅图像中有相同的景物,那么使用某种方法分别提取各自的稳定点,这些点之间会有相互对应的匹配点。所谓关键点,就是在不同尺度空间的图像下检测出的具有方向信息的局部极值点。根据归纳,我们可以看出特征点具有的三个特征:尺度方向大小己0]/3/己7
- 2020-06-29下载
- 积分：1
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基于VHDL的FPGA串口通信
基于VHDL的FPGA串口通信验证实现和PC机进行基本的串口通信的功能
- 2020-12-08下载
- 积分：1
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基于二维元胞自动机的交通流模拟分析
二维元胞自动机 基于二维元胞自动机的交通流模拟分析44http://xbbjb.swu.cn38St(i,j)=F[S(i,j),S,(i-1,j),S,(i+1,j),S,(i,j-1),S,(i,j+1)](1)BMI(1)BMIT=4t=341843.2/(N×N)NXN(AJAVAT=232×32,64×64,128128,256×256,512×512,T=4128×128MATLAB01100002000∷;酸(a)暂念的渐近状态(b)暂心的阻塞状态3128×128128×128C1994-2013CHinaAcademicJOurnalElectronicPublishingHouse.Allrightsreservedhttp://www.cnki.net643平均速度与密度关系图1.0平均速度曲线L32×320L=64x=128×1280808=256×2560.7512x512060.6053.330H040.30.20.2w0.10152253035404500.2040.6081.012141.61820密度/时间步10T=25128×1280.34.3BMLT0.80.60.4502eBMI02515密度/6128×128BMI(T-2T-4)BMIBMI[1 NAGEL K, SCHRECKENBERG M. A Cellular Automaton Model for Freeway Traffic [J]. Journal of Physique, 19922:221-2292 HAM O, MIDDLETON AA, LEVINE D. Self-Organization and a Dynamical Transition in Traffic Flow Models [J]Physical Review E, 1992(10):6124-6127L3 FUKUI M. ISHIBASHI Y. Traffic Flow in 1D Cellular Automaton Model Including Cars Moving with High Speed LJJ996,65(6):1868-1872005,54(10):4621-4626,2010,10(2):122-128C1994-2013cHinaAcademicJournalElectronicPublishingHouse.Allrightsreservedhttp://www.cnki.net46http://xbbjb.swu.cn38On Simulation and analysis on Traffic Flow Based onTwo-Dimensional Cellular automationMEI Hong, CHENG WeiZHANG Yun-sheng, YU Peng-cheng1. Faculty of Continuing Education, Kunming University of Science and Technology, Kunming 650051, China;2. Faculty of Transportation Engineering, Kunming University of Science and Technology, Kunming 65005 1, ChinaFaculty of Information Engineering and Automation, Kunming University cf Science and Technology, Kunming 650051. China4. Computer Center, Kunming University of Science and Technology, Kunming 650051. ChinaAbstract: BML model is a two-dimensional cellular automata model, which is especially used to simulateand analy ze the traffic system. We use Java language to implement this model. With this model, the re-ationship between the average velocity and the average density has been found by computer simulationThe phase transition and self organization have also been faund. And at last, the bml model improved intraffic light cycle changes for exploring more valuable to the research and applicationKey words: two-dimensional cellular automation; traffic flow; BML modelC1994-2013CHinaAcademicJOurnalElectronicPublishingHouse.Allrightsreservedhttp://www.cnki.net
- 2020-12-11下载
- 积分：1
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大量纠错码码编译码的源代码
大量纠错码包括rs码编译码源代码，有限域的工具包
- 2020-12-10下载
- 积分：1
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微信抽签&微信求新年签源码 新年签 吸粉丝 朋友圈 微信求签.
非常火的微信抽签&微信求新年签源码 淘宝上卖200元 新年签 吸粉丝 朋友圈 微信求签不多解释了。完美无措！！！
- 2020-11-30下载
- 积分：1
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lz4-r127.tar.gz
这个源码很不好早，，在此提供给大家参考和使用
- 2020-12-01下载
- 积分：1
