【作者】 孙颢；

【导师】 韦娟；

【作者基本信息】 西安电子科技大学 ， 空间信息科学， 2010， 硕士

【摘要】 随着全球卫星导航系统的迅速发展,新一代卫星导航接收机越来越受到研究者和工业界的关注。基于软件无线电思想的GPS软件接收机由于其功能的易重配性及信号处理单元的易实现性等优点,成为近些年国内外科研机构的研究热点。GPS软件接收机具有模块化、可编程、灵活和适应性强等特点,同时可兼容多种导航系统。通过软件接收机的研究,可以为研制我国自主的北斗导航系统接收机提供理论参考和借鉴。本文主要对基于软件无线电思想的GPS接收机的算法进行了研究。首先介绍了GPS系统构成及卫星信号的组成、调制方式;其次讨论了GPS软件接收机的基带信号处理算法,包括GPS信号的捕获与跟踪,目的是得到GPS信号中的导航电文信息和C/A码相位、多普勒频移等观测量;然后分析了GPS定位算法,根据提取到的导航电文信息,得到GPS卫星在轨的瞬时位置,同时结合伪距信息,进行伪距方程的求解,最终解算出用户接收机的位置;最后,在对实际的硬件GPS接收机功能模块进行分析抽象的基础上,结合面向对象的思想,使用C++语言实现了一个软件接收机,并验证了最终的处理结果。更多还原

【Abstract】 With the rapid development of the Global Navigation Satellite System, there is a growing tendency among the researchers who focus on realization of GNSS software receiver. Because of its advantages such as its easy reconfiguration characteristics of function module and easy to change property of signal processing module, the Software defined radio based receiver has been regarded as a hot research subject. GPS software radio receiver is developed for its advantages on modularization, programming, flexibility and adaptability. Also it is compatible with a variety of navigation systems. The study on GPS could provide reference for Chinese BD navigation system.In the paper, the principles of GPS software receiver based on software radio are researched, and the algorithms for baseband signal processing and positioning resolution are mainly focused on. Firstly, the system architecture and the principles of GPS are introduced; then the signal format and modulation. Secondly, in order to obtain the navigation data, C/A code phase and Doppler frequency shift, the algorithms of baseband signal processing are discussed, including acquisition and tracking. Then, the algorithms of positioning resolution are analyzed. Navigation data and pseudo range are acquired from baseband processing results, thus user position would be calculated. Finally, a software radio receiver is implemented by using the C++ programming language, according to the analysis of the modules’properties of the hardware receiver and the theory of OOP.更多还原