压缩解压算法LZ77算法有许多派生算法(这里面包括 LZSS算法)。它们的算法原理上基本都相同，无论是哪种派生算法，LZ77算法总会包含一个动态窗口（Sliding Window）和一个预读缓冲器（Read ahead Buffer）。动态窗口是个历史缓冲器，它被用来存放输入流的前n个字节的有关信息。一个动态窗口的数据范围可以从 0K 到 64K，而LZSS算法使用了一个4K的动态窗口。预读缓冲器是与动态窗口相对应的，它被用来存放输入流的前n个字节，预读缓冲器的大小通常在0 – 258 之间。这个算法就是基于这些建立的。用下n个字节填充预读缓存器（这里的n是预读缓存器的大小）。在动态窗口中寻找与预读缓冲器中的最匹配的数据，如果匹配的数据长度大于最小匹配长度 （通常取决于编码器，以及动态窗口的大小，比如一个4K的动态窗口，它的最小匹配长度就是2），那么就输出一对〈长度（length），距离（distance）〉数组。长度(length)是匹配的数据长度，而距离(distance)说明了在输入流中向后多少字节这个匹配数据可以被找到。
上传时间： 2014-01-22
上传用户：tzl1975
This book explains how to write device drivers for the newest members of the MicrosoftWindows family of operating systems using the Windows Driver Model (WDM). In this Introduction, I ll explain who should be reading this book, the organization of the book, and how to use the book most effectively. You ll also find a note on errors and a section on other resources you can use to learn about driver programming. Looking ahead, Chapter 1 explains how the two main branches of the Windows family operate internally, what a WDM device driver is, and how it relates to the rest of Windows.
标签： MicrosoftWindows the explains drivers
上传时间： 2014-01-04
上传用户：dongqiangqiang
It’s your first day in the lab.Undoubtedly you are experiencing a range of emotions: excitement, curiosity, anxiety. You will be working in this lab and with a group of people, as well as with your supervisor, for several years to come. This is the first day of a long commitment and, for some, a hard road ahead. Which is why it’s important to get off on the right foot.
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上传时间： 2017-09-14
上传用户：zhangyi99104144
PrefaceDuring the past years, there has been a quickly rising interest in radio access technologies for providingmobile as well as nomadic and fixed services for voice, video, and data. The difference indesign, implementation, and use between telecom and datacom technologies is also becoming moreblurred. One example is cellular technologies from the telecom world being used for broadband dataand wireless LAN from the datacom world being used for voice-over IP.Today, the most widespread radio access technology for mobile communication is digital cellular,with the number of users passing 5 billion by 2010, which is more than half of the world’s population.It has emerged from early deployments of an expensive voice service for a few car-borne users,to today’s widespread use of mobile-communication devices that provide a range of mobile servicesand often include camera, MP3 player, and PDA functions. With this widespread use and increasinginterest in mobile communication, a continuing evolution ahead is foreseen.This book describes LTE, developed in 3GPP (Third Generation Partnership Project) and providingtrue 4G broadband mobile access, starting from the first version in release 8 and through the continuingevolution to release 10, the latest version of LTE. Release 10, also known as LTE-Advanced,is of particular interest as it is the major technology approved by the ITU as fulfilling the IMTAdvancedrequirements. The description in this book is based on LTE release 10 and thus provides acomplete description of the LTE-Advanced radio access from the bottom up.Chapter 1 gives the background to LTE and its evolution, looking also at the different standardsbodies and organizations involved in the process of defining 4G. It also gives a discussion of the reasonsand driving forces behind the evolution.Chapters 2–6 provide a deeper insight into some of the technologies that are part of LTE and itsevolution. Because of its generic nature, these chapters can be used as a background not only for LTEas described in this book, but also for readers who want to understand the technology behind othersystems, such as WCDMA/HSPA, WiMAX, and CDMA2000.Chapters 7–17 constitute the main part of the book. As a start, an introductory technical overviewof LTE is given, where the most important technology components are introduced based onthe generic technologies described in previous chapters. The following chapters provide a detaileddescription of the protocol structure, the downlink and uplink transmission schemes, and the associatedmechanisms for scheduling, retransmission and interference handling. Broadcast operation andrelaying are also described. This is followed by a discussion of the spectrum flexibility and the associated
上传时间： 2022-07-08
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