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Q260046902专业做论文I基于FPGA的ASK载波传输系统设计摘要：现代通信系统的发展随着VHDL等设计语言的出现和ASIC的应用进入了一个新的阶段，普通的传输系统设计方法已经不能满足使用需求。由于大多数信号都是带通型的，所以必须先用数字基带信号对载波进行调节，形成数字调制信号再进行传输。因而，调制技术是实现现代通信的重要手段。本文在研究ASK传输系统的基础上，基于FPGA设计了它的调制解调仿真实现方案。首先确定了ASK传输系统的仿真方案。其次编写了方案所需的程序，包括基带信号的产生，调制及解调实现功能。最后，对整个系统进行仿真，对结果中的错误进行分析并改进方案。结果表明用FPGA控制ASK传输系统的实现方法简单，误码率低。提高了数字通信系统的效率，降低了成本。关键词：ASK技术；调制；解调；误码Q260046902专业做论文IIThedesignofASKcarriertransmissionsystembasedonFPGAAbstract:ThedevelopmentofmodernCommunicationsystementersonanewstagealongwiththeappearanceofVHDLandimplementofASIC.Themethodofordinarytransmissionsystemdesignalreadycouldnotmeettheoperationrequirements.Becausemostoftherealsignalarebandpasssignal,itisnecessarytousebasebandsignaltomodulatecarrierwaveandgeneratedigitalmodulationsignaltobetransferred,thusthetechnologyofthemodulationanddemodulationistheimportantmethodsofthemoderncommunication.BasedonthestudyofASKcarriertransmissionsystem,thesimulationonASKmodulationanddemodulationhasbeendesignedbasedonFPGA.Firstly,thedesignofsimulationonASKcarriertransmissionsystemwaschosen.Secondly,therequiredprocedurehascompiled,includingbasebandsignalproducing,functionofmodulationanddemodulationrealizing.Finally,thesimulationontheoverallsystemwasconducted.Then,theresultmistakewasanalyzedandthedesignwasimproved.Theresultindicatesthemethodofdemodulation,whichcontroltheoutputofASKbyFPGA,issimple.Theerrorcoderateislow.Theefficiencyisimproved.Theefficiencyofdigitalcommunicationsystemisadvancedandthecostislowered.Keywords:Amplitude-shiftkeyingtechnology,Modulation,Demodulation,ErrorcodeQ260046902专业做论文III目录第1章绪论·······················································································11.1课题背景····················································································11.2课题目的和意义···········································································21.3论文内容安排··············································································3第2章方案的设计·················································································42.1方案涉及的技术···········································································42.1.1通信系统的调制解调技术························································42.1.2ASK调制解调技术································································82.2整体方案设计············································································132.3本章小结··················································································14第3章ASK调制系统软件仿真································································153.1调制系统仿真建模······································································153.2调制程序··················································································153.3ASK调制系统仿真·····································································173.4仿真结果调试············································································183.5本章小结··················································································20第4章ASK解调系统软件仿真································································214.1解调系统仿真建模······································································214.2解调程序··················································································214.3ASK解调系统仿真·····································································224.4仿真结果调试············································································234.5本章小结··················································································25第5章ASK调制与解调系统综合仿真·······················································265.1基带信号的输入·········································································265.1.1m序列简介········································································265.1.2m序列的实现·····································································275.2综合仿真··················································································29Q260046902专业做论文IV5.3仿真结果调试············································································305.4本章小结··················································································33结论·······························································································34致谢·······························································································35参考文献·······························································································36附录：源程序·······················································································37西南科技大学本科生毕业论文1第1章绪论1.1课题背景现代通信系统是时代生命线。现代通信已经不再是单一的电话网或电报文字通信网，而是一个综合的为多种信息服务的通信网。为适应世界性的政治与经济活动的需要，人类已经迅速建立起世界性的全球通信网。通信网已经成为支撑现代经济的最重要的基础结构之一。改革开放以来，我国的通信建设有了迅速的发展，但与一些发达国家相比还是比较落后。随着时代的发展，用户不再满足于听到声音，而且还要看到图像；通信终端也不局限于单一的电话机，而且还有传真机和计算机等数据终端。现有的传输媒介电缆、微波中继和卫星通信等将更多地采用数字传输。传递信息所需的一切技术设备的总和称为通信系统。图1-1为通信系统的一般模型。图1-1通信系统的一般模型图1-1中，信息源可以通过输出信号的性质不同分为模拟信源和数字信源，由于信息源产生信息的种类和速率不同，因而对传输系统的要求也各不同。发送设备的基本功能是将信源和传输媒介匹配起来，即将信源产生的信息信号变换为便于传输的信号形式，送往传输媒介，调制是最常见的变换方式。发送设备还包括为达到某种特殊要求所进行的各种处理，如多路复用、保密处理、纠错编码处理等。传输媒介是从发送设备到接收设备之间信号传递所经过的