通信电子线路实验(通信)解读 下载本文

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通信电子线路实验

上海师范大学 信息与机电工程学院

前 言

通信(高频)电子线路课程是大学本科电子类专业的必修课之一,其相应的实验课程,也是非常重要的。它为学生巩固所学理论知识,开拓思路,增加动手能力提供了实践平台。

本系列实验参考了《电子线路-非线性部分》谢嘉奎主编、《高频电子线路》张肃文主编,等教材的相关内容而编写的。实验内容包括振荡器、调频、调幅、波形变换、综合类实验等,约13个实验。可以基本满足对理论教材的覆盖面。如果需要,还可以延伸出更多相关的实验内容。

实验系统由实验平台和若干个独立实验模块组成,实验平台自带直流电源(+12V、+5V、-12V、-5V)。实验模块以插板的形式插在实验平台上,除需调节和拨动的器件外,其它元件均焊接在PCB板上。模块正面印有实验电路图,便于学生理解实验原理。反面使用透明盒罩,便于学生观察元件,又可对元件加以保护。

本实验课程内容适合高校通信和电子信息专业学生学习,若本教材在使用中发现不妥或错误之处,欢迎同学和老师指正。

上海师范大学

信息与机电工程学院

王晨 王芳

2015.10于上海

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目 录

实验一 高频小信号调谐放大器 ···························································· 4 实验二 三点式LC振荡器与压控振荡器 ················································ 8 实验三 波形变换电路 ······································································· 13 实验四 模拟乘法器调幅电路 ······························································ 17 实验五 集电极调幅 ·········································································· 20 实验六 二极管峰值检波器 ································································· 23 实验七 锁相环调频 ·········································································· 26 实验八 锁相环鉴频 ·········································································· 29 实验九 调幅语音通话 ······································································· 32 实验十 调频/调幅接收系统 ································································ 35 附录 计算机辅助分析软件及应用 ························································ 38 第一节 OrCAD简介 ········································································ 38 第二节 高频小信号单调谐放大器的仿真 ·············································· 40 第三节 LC振荡器的仿真 ·································································· 49

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实验一 高频小信号调谐放大器

一、实验目的

1、掌握高频小信号调谐放大器的工作原理;

2、掌握谐振放大器电压增益、通频带、选择性的定义、测试及计算方法。

二、实验内容

1、测量各放大器的电压增益;

2、测量放大器的通频带与矩形系数(选做); 3、测试放大器的频率特性曲线(选做)。

三、实验仪器

1、20MHz示波器 一台 2、数字式万用表 一块 3、调试工具 一套

四、实验基本原理

1、单级单调谐放大器

+12VCC2R27C19T2TT2TP5W3Q2R31C17R28R30C18

图1-1 单级单调谐放大器实验原理图

实验原理图如图1-1所示,本实验的输入信号(10.7MHz)由正弦波振荡器模块的石英晶体振荡器或高频信号源提供。信号从TP5处输入,从TT2处输出。调节电位器W3可改变三极管Q2的静态工作点,调节可调电容CC2和中周T2可改变谐振回路的幅频特性。

2、双级单调谐放大器

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