td-scdma直放站数字中频模块的研究和设计.docx

浙江工业大学硕士学位论文
TD—SCDMA直放站数字中频模块的研究和设计
摘要
随着信息技术的快速发展,小数据量的通信能力已经不能满足人们丰富的业务需求, 窄带数字系统正逐步向第三代宽带数字移动通信发展。,是我国拥有自主知识产权的3G国际标准。目前,,。
直放站将是TD—SCDMA移动通信网络的重要组成部分,直放站的应用不仅可以增加 ,使施主基站的覆盖得到延伸,也能增加空闲基站的话务负荷,或是分摊繁忙基站的话务量,还可以起到优化网络等作用。直放站可以灵活地安装在地铁,商场等信号盲区和边远地区,,采取以基站为主、直放站做适当补充的混合组网方式是很有意义的。
(TDD)的影响,需要研究相应的通信标准。数据通过无线帧传输,帧划分为不同的时隙,上下行的数据通过时隙传输,上下行的时隙可以灵活分配,,首先需要确定上下行时隙的切换点,然后分别对上下行信号进行射频功率放大。要确定上下行时隙的切换点,需要将射频信号转化为基带信号进行处理。受技术水平限制,直接对射频信号采样处理还有一定难度,本设计采用数字化中频技术,将射频信号转化到中频模拟信号,然后再对其进行中频采样和数字下变频, 输出基带IQ信号,。
、。,,在Quartus II环境下,对数字下变频器作了设计和仿真,最后对基于专用下变频器AD6654的同步开关控制模块的结构作了设计。
关键词:直放站,,数字中频,下变频
浙江工业大学硕士学位论文
THE RE SEARCH AND DE SIGN OF DIGITAL INTERMEDIATE FRE QUENCY MODULE
oF REPEATER
ABSTRACT
Along with fast development of information technical,municate ability of small quantity has already cail’t satisfied the business requirement of narrow band munication system is developing gradually to the wideband third generation mtmication —SCDMA is one of air technical criterion of the third
generation munication system released by ITU,first brought forward by , the TD—SCDMA industry has already had the petition ability,OUr country is also pushing the development of the TD-SCDMA industry strongly.
TD-SCDMA repeater will be all important part of the munication
only increase work covery ability,extend the base station,it also increase the telephone traffic load of the idle base station and optimize Can be flexible placed in the signal blind area like underground and base station as principle,repeater as makeup is very of the influence of the TDD,TD—SCDMA repeater needs to study r