搶答器是一種智力競賽常用的器件,搶答器的設計方法千差萬別,文章利用常用的數字電子器件,設計了八路搶答器電路的設計、仿真及實現的全過程,提出兩種可行的設計方案:方案1采用74ls373實現電路鎖存,74ls148實現電路編碼,74ls74及數碼管實現電路顯示;方案二采用CD4511BCN和LMC555CM集成電路及數碼管實現搶答器的控制和顯示。本文設計用的器件簡單,容易理解,適用于初學電子技術的人員。Answer scrambler is a common device in intelligence competition, and its design methods vary greatly. This paper designs the whole process of design, simulation and Realization of the circuit of eight-way answer scrambler by using common digital electronic devices, and puts forward two feasible design SCHEMES: scheme 1 uses 74 ls373 to realize circuit latching, 74 ls148 to realize circuit coding,74 ls74 and digital tube to realize circuit. The second scheme uses CD4511 BCN, LMC555 CM integrated circuit and digital tube to control and display the answerer. The device designed in this paper is simple and easy to understand, and it is suitable for the beginners of electronic technology.
標簽：
搶答器
上傳時間：
2022-04-05
上傳用戶：
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
標簽：
4g
移動通信
上傳時間：
2022-07-08
上傳用戶：
