电子信息工程毕业论文---CDMA数字移动通信系统信道编码的实现.doc

毕业论文 CDMA数字移动通信系统信道编码的实现 专业名称： 电子信息工程 班 级： 2005级1班 摘要 CDMA技术是当前无线电通信，尤其是移动通信的主要技术，不论是在中国已经建立的IS-95规范的中国联通CDMA网、各大移动通信运营商正准备实验及建立第三代（3G）系统还是大设备研发商已经在开发的三代以后（也称为4G）带宽的移动通信系统，CDMA都是主要的选择。CDMA概念可以简单地解释为基于扩频通信的调制和多址接入方案。其反向链路有接入信道和反向业务信道组成。接入信道用于短信令消息交换、能提供呼叫来源、寻呼响应、指令和注册。本设计CDMA通信系统信道进行。首先，通过学习相应的理论知识，熟悉接入信道实现的过程，对每一步的原理有了较深的理解，ALTERA 的MAX+ PLUS II系统来开发，它具有强大的功能，支持原理图、硬件描述语言(VHDL,AHDL, verilogHDL）FPGA来实现数字移动通信信道编码，大大简化了系统结构。而且VHDL描述语言的使用缩短了开发时间，增强了系统的可读性，便于后续产品的升级。最后，逐步地对各个模块进行分析、仿真与验证。目的是通过毕业设计工作熟悉现代无线通信系统的基本构成与基本工作原理，重点掌握CRC积编码、块交织等相关编码技术，并能将这些技术应用实际系统设计。扩频通信； 码分多址； 信道编码； FPGA ACDMA is the major technology used in the wireless communication, especially in the mobile communication. Following the IS-95 standard set up in China, CDMA is the mostly choice whether in China Uninet net, in the third system (3G) that all kinds of mobile businessmen are to build or in the wider system than the third one (named 4G) that the large equipments researching businessmen have been researching. The concept of CDMA may be interpreted as the simulation that base on frequency spreading and the multiply address access project. Its reverse channel is composed of access channel and traffic channel. The access channel is used for brief information exchanging 、providing the source about the calling、the call responding 、the instruction and the enrollment. The channel code of CDMA communication system is realized in the design. First, the process of connect channel will be familiar; the principle of every step of the procedure about the channel will be understood, after the study of the relating knowledge. Then, with ALTERAs MAX+PLUS II development system, which has powerful functions to support the schematic diagram, hardware description language (VHDL, AHDL, verilogHDL) and other input methods. Using FPGA to realize digital mobile communication channel encoding, greatly simplifies the system architecture. Description language VHDL and the use of shorter development time and enhance