基于MATLAB的PCM 编译码器的实现.doc

正文 基于MATLAB的PCM 编译码器的实现 摘要：随着信息技术的发展，通讯在人们的日常生活中发挥着越来越重要的作用。进入21世纪，信息的传递更是越来越广泛和快捷，现代通讯的发展方向是数字化，因为数字通信不仅能实现人与人、人与机器、机器与机器之间的通信和数据交换功能，而且具有比模拟通信系统更好的性能。PCM编码就是一种将模拟信号数字化以及数字信号模拟化的实现过程。编码过程就是将模拟信号经过抽样、量化、后编为数字信号的过程，译码是其反变换。本文通过仿真软件MATLAB强大的仿真功能实现了其编译过程，通过编译码图形对比分析了误差，并提出了进一步缩小误差的方案。PCM原理常应用于现代语音通信中。 关键词：、PCM、13折线法、抽样、量化、编码、  Long XiaoBo (Physical Science And Electronal Technolony Department of Hexi University Zhangye Gansu ,734000) Abstract: Along with the information technology development, the communication is playing the more and more vital role in peoples daily life.Enters for the 21st century, the information transmission is more and more widespread and quickly, the modern communication development direction is the digitization, not only because the digital communication can realize between the human and the human, the human and the machine, the machine and the machine correspondence and the data exchange function, moreover has compared to an analog communications system better performance.The PCM code will be one kind the simulated signal digitization as well as the digital signal simulation realization process.The code process is the simulated signal after sampling, the quantification, posts-edit for the digital signal process, the decoding is its inverse transformation.This article has realized its translation process through the simulation software MATLAB formidable simulation function, through arranged the decoding graph contrast to analyze the error, and proposed further reduced erroneous the plan.The PCM principle often applies in the modern pronunciation correspondence. Key word: PCM, 13 broken-line methods, sampling, quantification, code,  引言 通信技术的发展经历了一段漫长的历史，我国古代的商周时期人们就知道用烽火来远距离传递消息，实现通信。语音通信真正的起源来自欧洲17世纪英国著名的物理学家和化学家罗伯特?胡克首先提出了远距离传送话音的建议。在1796年，休斯提出了用话筒接力传送语音信息的办法。目前，大家公认的电话发明人是贝尔，他是在1876年2月14日在美国专利局申请电话专利权的。 PCM（Pulse code modulation）的概念是在1937年就由法国工程师瑞维斯（A.H.reeve）提出.但限于当时的水平,直到1946年美国的BELL实验室才制造出第一台PCM数字电话终端机。20世纪60年代以后，晶体管PCM终端机开始大量用于市话网的中继线