【作者】 寿心灵；

【导师】 李书芳；

【作者基本信息】 北京邮电大学 ， 电磁场与微波技术， 2007， 硕士

【摘要】 近年来，高质量的无线视频传输一直是人们的研究重点。目前市场上的无线视频传输产品有限，并且无法满足视频的高质量、远距离和快速移动等传输要求。为了解决这一矛盾，急需开发一种新型的无线视频传输系统来填补市场的空白。这个系统由MPEG4制式的视频压缩解压缩部分、基带部分以及宽带的射频收发信机三部分组成。本论文的主要内容是340MHz射频收发信机部分电路的设计实现。本系统的基带采用了OFDM技术，以提高系统的抗干扰能力和快速移动下的传输要求。论文首先简单介绍了项目背景，然后在第二章介绍了无线射频收发信机的理论，包括目前广泛应用的收发信的分类，各类收发信机的优势和缺点，衡量收发信机性能的主要指标。第三章介绍了整个视频传输系统的方案和结构，并对射频收发信机部分结构设计、性能设计参数进行了介绍和描述。在第四章中，分别详细论述了本项目射频收发信机各部分的具体实现，如：混频器、微波滤波器、高功放以及低噪声放大器、中频自动增益控制等，并对各实现模块的性能指标进行了介绍。此外，在介绍各收发信机各模块具体实现前，还从理论设计上进行了论述，并介绍了衡量各部分性能的主要指标和重要概念。第五章重点论述了射频收发信机的常用指标和单板性能测试的测试方法，以及本系统收发信机部分的实验测试结果。由于本课题主要任务是硬件电路的实现，因此在最后一章中，还结合自身设计的经验，介绍了进行高频电路设计需要考虑的问题，特别是电磁兼容(EMC)原则。射频电路设计中一个很重要的部分就是电路板的设计和结构设计。这一章中，讨论了在具体电路设计当中需要注意的问题，包括器件布局、电路板布线、接地、电源退耦和屏蔽技术。更多还原

【Abstract】 Recently, high quality wireless video transmission has always been the research emphasis. There are limited wireless video transmission product, which can not satisfy the requirement of video transmission, such as high quality, telecommunication and fast motion, in the current market. In order to solve it, a new wireless video transmission system is required to meet the market.The system is composed by three main part: the MPEG4 video compression and decompression, the baseband and wide band radio frequency transceiver.This paper is focus on the design and realization of part circuit in the 340MHz radio frequency transceiver. OFDM technology is applied in baseband to improve the anti-interference ability and transmission requirement at fast motion. Firstly, the background of the program is introduced. Secondly, the following is the theory of the wireless radio frequency transceiver, including the classification of common transceiver, the advantage and disadvantage of varied transceiver, the main guidelines of transceiver performance.In the third chapter, the design and structure of the video transmission system is described, moreover, the design of part structure of the radio frequency and the performance parameter are introduced.In the forth chapter, the realization of each part of the radio frequency transceiver and the performance of each module are discussed in detail, such as, the mixer, microwave filter, high frequency power amplifier, low noise amplifier(LNA), intermediate frequency auto gain amplifier(AGC), and etc.. Moreover, before the introduction of the realization of the transceiver’s each module, the theory, the important concept and the main performance of each module should be elaborated first.In the fifth chapter, the content mainly includes the common guideline and the test methods of the single band, and part of the test result of the transceiver.Since the main task of the program is to realize the hardware circuit, these contents under my design experience are introduced, including, the issues that in consideration of the high frequency circuit design, especially the electro magnetic compatibility (EMC). One important part of the radio frequency circuit design is the structure of the printed circuit board (PCB). In the chapter, the aspects required attention are discussed, including, the apparatus layout, the PCB layout, grounding, power decoupling and shielding.更多还原