视频信号调制发射机

视频信号调制发射机

摘要：本次制作的视频信号调制发射机主要由视频信号的调制，压控振荡器，锁相环，各级功率放大以及单片机程序控制组成。通过锁相环（PLL）产生的稳定频率的载波（48MHz—88MHz）对视频信号进行调制。锁相环由鉴相器（PD）、环路滤波器（LF）和压控振荡器（VCO）组成，主要通过频率合成器MC145152、分频器MC12022、运放LM358等芯片实现，可将压控振荡器产生的载波频率稳定在48MHz—88MHz的任意一个频率值。调制芯片采用日本进口的UPC1507

集成电路。功率放大选用三极管9018，采用单调谐回路对发射信号进行放大。以STC89C52单片机为控制核心通过改变频率合成器MC145152实现频道的选择。液晶屏1602承担载波频率的显示。

关键字：视频信号锁相环ASK调制

video signal transmitter

Abstract: video signal transmitter consists mainly of modem phase lock loop, power amplifiers, control and modulation several parts, in order to realize the video signal transmission of radio. Through the phase lock loop (PLL) of 48MHz carrier (88MHz video signal) -- as we modulation. By MC145152 PLL chip, would MC12022 and vco produces the carrier frequency stability in the 48MHz 88MHz - an arbitrary frequency value. Modulation chip adopt UPC1507 integrated circuit chips, the develepment and peripheral circuit less, can achieve good image, will phase-locked loop indexes of UPC1507 into video signal with software-processable on amplitude. Power amplifier, the single 9018 triode selection of transmitting signals are tuned circuits. With

AT89C51 as the core to realize that the choice and channel carrier frequency.

Key words: video signal phase lock loop itinerary

目录

1、系统方案设计 .....................................................

1.1 设计任务..................................................

1.2 整体方案设计..............................................

1.2.1 设计思路............................................

1.2.2 设计方案比较论证....................................

1.3 系统框图..................................................

2、理论分析计算与电路设计 ...........................................

2.1 压控振荡器的设计...........................................

2.2 锁相环电路的设计...........................................

2.2.1 锁相环分频原理及计算................................

2.2.2 鉴相器原理 .........................................

2.2.3 环路滤波器的设计....................................

2.3 调幅电路的设计.............................................

2.4 功率放大电路设计...........................................

2.5 控制电路的设计 ...........................................

3、系统软件设计....................................................

4、系统测试.........................................................

4.1 测试使用的仪器.............................................

4.2 数据测试和测试结果及分析...................................

4.2.1 锁相环部分测试.........................................

4.2.2 高频功放部分测试......................................

参考文献............................................................. 附录1 使用说明..................................................... 附录2 主要元器件清单............................................... 附录3 电路原理图及印制板图......................................... 附录4 程序清单.....................................................