n the first part of this book, we give an introduction to the basic applications of wireless com- munications, as well as the technical problems inherent in this communication paradigm. After a brief history of wireless, Chapter 1 describes the different types of wireless services, and works out their fundamental differences. The subsequent Section 1.3 looks at the same problem from a different angle: what data rates, ranges, etc., occur in practical systems, and especially, what combination of performance measures are demanded (e.g., what data rates need to be transmitted over short distances; what data rates are required over long distances?) Chapter 2 then describes the technical challenges of communicating without wires, putting special emphasis on fading and co-channel interference. Chapter 3 describes the most elementary problem of designing a wireless system, namely to set up a link budget in either a noise-limited or an interference-limited system. After studying this part of the book, the reader should have an overview of different types of wireless services, and understand the technical challenges involved in each of them. The solutions to those challenges are described in the later parts of this book.
标签： Communications Wireless Edition 2nd
上传时间： 2020-06-01
上传用户：shancjb
Wireless networking is undergoing a transformation from what has been primarily a medium for supporting voice traffic between telephones, into what is increasingly becoming a medium for supporting traffic among a variety of digital devices transmitting media of many types (voice, data, images, video. etc.) Wireline networking underwent a similar transformation in the 1990s, which led to an enormous build-up in the capacity of such networks, primarily through the addition of new optical fiber, switches and other infrastructure.
标签： Multiusers Detection Wireless Networks
上传时间： 2020-06-01
上传用户：shancjb
Dear Reader, this book project brings to you a unique study tool for ESD protection solutions used in analog-integrated circuit (IC) design. Quick-start learning is combined with in-depth understanding for the whole spectrum of cross- disciplinary knowledge required to excel in the ESD field. The chapters cover technical material from elementary semiconductor structure and device levels up to complex analog circuit design examples and case studies.
标签： Circuits Design Analog ESD for
上传时间： 2020-06-05
上传用户：shancjb
VK0384是一个48x8的LCD駆动器. 可软件程控使其适用于多样化的LCD应用线路. 仅用到3至4条讯号线便可控制LCD駆动器,除此之外亦可介由指令使其进入省电模式 特色 工作电压 : 2.4V~5.2V 内建 256KHz RC oscillator 提供 1/4 偏压 1/8 COM 周期 省电模式 48x8 LCD駆动器 内建 48x8 bit 显示内存 3-wire serial interface 软件程控 资料及指令模式 自动增加读写地址
上传时间： 2020-06-05
上传用户：shubashushi66
The “bottom-line” metrics of cash flow, demand, price, and return on investment are driven by a second set of financial metrics represented by value to the customer, cost, and the pace of innovation. Get them right relative to competition and impressive bottom-line results should follow. Because of their importance, we call value to the customer, variable cost, and the pace of innovation the “fundamental metrics.”
标签： Planning Product Systems Driven Value and
上传时间： 2020-06-06
上传用户：shancjb
I would like to thank you for purchasing the second edition of “Industrial Network Security,” especially if you are one of the many supporters of the first edition. When the second edition was announced, many people asked me, “why a second edition?” and even more followed that up with, “and why a coauthor?” These ques- tions are harder to answer than you would think.
标签： Industrial Security Network
上传时间： 2020-06-07
上传用户：shancjb
写一个HIS系统界面，要求的功能（从患者角度操作）： 注册/登录功能 挂号（选择科室，医生） 查看病历 查看药方 要求用到的技术： css用来对页面进行格式设置 jquery的事件操作 ajax读取json数据（仅用GET方法）
标签： JavaScript
上传时间： 2020-06-08
上传用户：15162964158
With all the recent hype over radio frequency identification (RFID) and the requirements to implement it, you might think that RFID can turn water into wine, transform lead into gold, and cure the world’s diseases. You might also be worried that RFID will enable Big Brother to track your move- ments to within a foot of your location from a satellite five hundred miles up in space. The truth is, RFID can do none of these things. In this chapter, you find out the basics of what RFID is, what forces are dri- ving RFID as a replacement for the bar code in the marketplace, and what benefits RFID can offer
标签： ForDummies_RFID_For_Dummies
上传时间： 2020-06-08
上传用户：shancjb
Software-defined radios (SDRs) have been around for more than a decade. The first complete Global Positioning System (GPS) implementation was described by Dennis Akos in 1997. Since then several research groups have presented their contributions. We therefore find it timely to publish an up-to-date text on the sub- ject and at the same time include Galileo, the forthcoming European satellite- based navigation system. Both GPS and Galileo belong to the category of Global Navigation Satellite Systems (GNSS).
标签： A_Software-Defined_GPS_and_Galile o_Receiver
上传时间： 2020-06-09
上传用户：shancjb
Phenomenon is an overused and overloaded term, but somehow it seems appropriate for Arduino—an endeavor that has caught the attention of an astonishingly wide range of people and provided opportunities for those who might otherwise have never picked up a soldering iron or written a single line of code. From dyed-in-the-wool hardware hackers to web page developers, robotics enthusiasts to installation artists, textile students to musicians: all can be found in the Arduino community. The versatility of the platform encompassing both hardware and software, combined with its inherent openness, has captured the imagination of tens of thousands of developers.
标签： Practical Projects Arduino Cool
上传时间： 2020-06-09
上传用户：shancjb
