基于Multisim调制解调仿真电路设计.doc

基于Multisim调制解调仿真电路设计 春芽电子科技 春芽ing 摘 要 通信电路系统中实现调制解调方法很多，而锁相环鉴频是利用现代锁相环技术来鉴频实现调制解调因为工作稳定、失真度小、信噪比高等优点被广泛应用。本课题分别设计2ASK、2PSK、2FSK的调制解调电路，功能是数字基带信号经过调制输出模拟信号，然后运用锁相环进行解调出数字信号，所以调制解调电路都运用Multisim软件进行仿真分析。对2ASK、2FSK、2PSK解调电路时低通滤波器输出的波形失真比较大，经过抽样判决电路整形后可以再生数字基带脉冲。整个硬件电路设计中，尽量做到电路简单实用，基本达到功能要求。 关键词：调制解调，Multisim仿真，锁相环 Abstract Communication circuit system to achieve a lot of modulation and demodulation, and the phase-locked loop frequency demodulation is the use of modern technology to achieve phase locked loop demodulation because the work is stable, low distortion, high signal noise ratio is widely used. This topic design of 2ASK, 2PSK, 2FSK modulation and demodulation circuit function is digital base band signal after the modulation output analog signal, then use the PLL to demodulate the digital signal, so modulation and demodulation circuit use Multisim software simulation analysis. The waveform distortion of the low pass filter output of 2ASK, 2FSK and 2PSK demodulation circuits is relatively large, and the digital baseband pulse can be regenerated by the sampling decision circuit. Throughout the hardware circuit design, as far as possible to achieve a simple and practical circuit, the basic requirements to achieve functional. Keywords: Modulation and Demodulation, Multisim Simulation, Phase Locked Loop 目 录 TOC \o 1-3 \h \u HYPERLINK \l _Toc23177 摘 要 PAGEREF _Toc23177 1 HYPERLINK \l _Toc28849 Abstract PAGEREF _Toc28849 1 HYPERLINK \l _Toc4899 1绪论 PAGEREF _Toc4899 3 HYPERLINK \l _Toc2814 1.1课题研究背景 PAGEREF _Toc2814 3 HYPERLINK \l _Toc7181 1.2 国内外发展现状 PAGEREF _Toc7181 3 HYPERLINK \l _Toc31853 1.3 课题主要研究内容 PAGEREF _Toc31853 3 HYPERLINK \l _Toc26706 2 锁相环基本原理 PAGEREF _Toc26706 4 HYPERLINK \l _Toc26243 2.1基本组成 PAGEREF _Toc26243 4 HYPERLINK \l _Toc11138 2.2工作原理 PAGEREF _Toc11138 4 HYPERLINK \l _Toc20032 3 2FSK调制解调电路设计 PAGEREF _Toc20032 6