GPS软件接收机载波跟踪环的设计实现  

Design of Carrier Tracking Loop in GPS Software Receiver

作　　者：刘高辉[1] 曹家昆[1] 

机构地区：[1]西安理工大学电子工程系,陕西西安710048

出　　处：《计算机仿真》2011年第1期348-351,共4页Computer Simulation

摘　　要：在接收机的信号优化问题的研究中,多普勒频移的跟踪是GPS信号解扩的关键技术之一。针对传统载波跟踪环路中由接收机加速度和加加速度引起的多普勒频移跟踪误差大的缺点,根据科斯塔斯(Costas)环实现载波跟踪的基本原理,为了减少信号误差,提出了接收机载波跟踪环路中鉴别器、滤波器和载波NCO的一种软件实现方法,推导出在不同动态环境下载波跟踪环路带宽和环路频率更新时间的理论值范围,最后对不同动态软件接收机接收的信号进行了跟踪仿真。结果表明:设计的载波跟踪环路功能正常,性能稳定,可快速精确地完成GPS信号的载波跟踪。Doppler frequency shift tracking is one of key technologies of the GPS signal dispreading. Acceleration of receiver and the jerk of the traditional carrier-tracking loop can cause large doppler frequency shift tracking error. Focusing at this defect, this paper achieved the basic principle of the carrier tracking based on the Costas loop. Not only a software implementation method including tracking loop in the discriminator, filter and carrier NCO proposed , but also the theoretical range of carrier tracking loop bandwidth and the loop frequency updating time in different dy- namic environments is deduced. Finally, various dynamic receiver tracking signals were simulated. The results showed that the function of the carrier tracking loop works properly and performances stably. It can track the GPS sig- nal carrier quickly and accurately.

关 键 词：导航软件接收机 载波跟踪 动态 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]