由于软件无线电技术具有模块化、灵活性强以及扩展性好等优点,使其成为目前无线通信系统新的研究热点,其核心是在通用的硬件平台上,通过加载不同的软件模块来实现不同的功能。主要介绍了软件无线电在接收机中的核心技术之一:码同步技术。详细阐述了码同步技术中的两个关键步骤:码捕获和码跟踪。并提出了一种新的捕获方法:分段相关捕获法;跟踪采用的是延迟锁定环的方法。利用Matlab仿真工具,对码同步算法进行建模仿真,证明了所设计的环路结构的正确性。然后利用Quartus Ⅱ开发软件,编写VerilogHDL代码,对接收端的码同步进行FPGA实现,并利用SignaltapⅡ在线逻辑分析仪对所设计的模块进行硬件仿真和测试。
As a result of the software radio technology which has advantages such as the modularization, flexibility and scalability, these make it become the new hotspot of the wireless communication system. This paper mainly introduce the code synchronization technology which is one of the core technology of the software radio in the receiver and elaborates on two key steps of the code synchronization technology: code capture and code tracking. We propose a new method of capture: segmented the related capture method and code tracking by delaying lock loop' s method. Writing Verilog HDL code in QuartusII software, we use FPGA to realize the code synchronization of the receiving terminal. Then we use the SignaltapII online logic analyzer to make the hardware simulation and test design of modules.