摘要
针对传统导航接收机采用模拟射频前端存在的缺陷,提出一种基于直接射频采样技术的导航接收机实现方法。根据当前公开的导航频段,将1.2 GHz和1.5 GHz的导航信号视为2个整体的带通信号,通过带通采样原理,选择可以兼容多频段导航信号的采样频率。为了解决射频采样后数据速率较高的问题,设计了一种基于抽取滤波和多相混频的数字下变频信号处理结构,可实现任意频点导航信号的降速、下变频和分离。该方法通过软件模块修改配置参数就可以实现多频点信号接收,极大地提高了系统的灵活性。通过Matlab对GPS L1的信号进行了仿真验证,结果表明该方法有效。
The signal based on BOC Modulation has been widely used in signal architecture design of global navigation systems.Compared with traditional BPSK signal,it can provide better tracking accuracy and better resistance to multipath.In view of pseudocode error capture caused by multipeak of autocorrelation function of BOC signal,four kinds of unambiguous acquisition methods of BOC signal are simulated and verified based on introduction of BOC signal feature,and the acquisition performances of these algorithms are compared and evaluated. The computer simulation results show that these four algorithms can effectively solve the problem of error capture of BOC signal,which has feasible significance for developing the performance advantage of BOC signal.
出处
《无线电工程》
2016年第6期45-47,68,共4页
Radio Engineering
基金
国家高技术研究发展计划("863"计划)基金资助项目(2012AA121802)
关键词
射频直接采样
带通采样
多频GNSS接收机
binary offset carrier（BOC）
unambiguous acquisition
autocorrelation function
