高动态TMBOC信号跟踪算法研究

发布时间：2018-04-07 18:44

本文选题：TMBOC　切入点：高动态　出处：《电子科技大学》2014年硕士论文

【摘要】：卫星导航系统是目前被应用于各行各业的焦点项目,世界各国都在积极组建属于自己的独立自主卫星导航系统。目前,全球的卫星导航系统包括GPS系统、伽利略系统、GLONASS系统以及中国的北斗导航系统,它们在定位、导航等各项领域发挥着重要的作用,服务于全球各个国家的军事和人民的生活当中。在高动态环境下,载体的高速度、高加速度以及高加加速度引起的多普勒频移给导航信号的捕获、跟踪和定位带来了极大的挑战,这一直是接收机算法研究中关注的问题。本文主要是针对高动态环境下,研究TMBOC调制体制下跟踪环路的设计方法,研究和实现稳定消除动态的跟踪算法,然后对具体的算法进行了MATLAB仿真验证和误差分析。本文分别介绍了GPS系统的定位原理以及TMBOC调制方式的原理,提出高动态环境下载波跟踪环在跟踪时会产生多普勒频移变化的问题,分析高动态对跟踪环路造成的影响。在此基础上,对该课题作以下几个方面的研究:(1)详细介绍了一种典型的高动态模型和信号模型,并对其速度、加速度及加加速度作了仿真结果展示,并建立了接收信号的高动态数学模型。(2)阐述了信号跟踪环路中载波跟踪环路及码跟踪环路的基本结构和算法,并对里面的具体模块算法进行了详细的分析,并对其测量误差进行了理论推导和仿真验证。(3)由于基于传统锁相环或锁频环技术的载波跟踪方案中所使用的相位或频率鉴别器和环路滤波器都不是基于最优准则而设计的,因此环路性能受到很大限制。在高动态环境下,导航卫星和导航接收机就地面而言的相对运动不稳定,导航接收信号的载波多普勒多频变化范围较大,当多普勒频移超出一定的范围的时候,锁频环路无法对信号载波频率进行多顶,这时候就需要一个辅助模块进行牵引,由于四项鉴频器能把±250 Hz频差牵引到±10左右的Hz范围内,那么本设计在信号载波多普勒频移较大时候,锁频环的鉴频器算法采用四项鉴频器,之后再对锁相结果进行三阶锁相环处理,最后在载波辅助的情况下进入码环路跟踪。
[Abstract]:At present, satellite navigation system is the focus of application in various industries. Every country in the world is actively building its own independent satellite navigation system.At present, the global satellite navigation system includes GPS system, Galileo system GLONASS system and China's Beidou navigation system, which play an important role in various fields, such as positioning, navigation, etc.To serve the military and the lives of the people of all countries around the world.In the high dynamic environment, the Doppler frequency shift caused by high velocity, high acceleration and high acceleration brings great challenges to the acquisition, tracking and positioning of navigation signals, which has always been a concern in the research of receiver algorithms.In this paper, the design method of tracking loop in TMBOC modulation system is studied, and the tracking algorithm to eliminate the dynamic stability is studied and realized. Then, the MATLAB simulation and error analysis are carried out for the specific algorithm.In this paper, the positioning principle of GPS system and the principle of TMBOC modulation are introduced, and the Doppler frequency shift of carrier tracking loop in high dynamic environment is put forward, and the influence of high dynamic on tracking loop is analyzed.On this basis, a typical high dynamic model and signal model are introduced in detail, and the simulation results of velocity, acceleration and acceleration are presented.The structure and algorithm of carrier tracking loop and code tracking loop in signal tracking loop are described, and the specific module algorithms are analyzed in detail.The measurement error is theoretically deduced and verified by simulation. (3) because the phase or frequency discriminator and loop filter used in the carrier tracking scheme based on the traditional phase-locked loop or frequency-locked loop technology are not based on the optimal criteria.Therefore, the loop performance is greatly limited.In the high dynamic environment, the relative motion of navigation satellite and navigation receiver is unstable on the ground, and the carrier Doppler multi-frequency variation range of the navigation received signal is large, when the Doppler frequency shift exceeds a certain range,The frequency locked loop can't carry out multiple top of the carrier frequency of the signal. At this time, an auxiliary module is needed for traction, because the frequency difference of 卤250 Hz frequency can be drawn to 卤10 Hz range by the four frequency discriminators.In this design, when the carrier Doppler frequency shift is large, the frequency discriminator algorithm of the frequency locking loop adopts four discriminators, and then the phase-locked results are processed by the third-order phase-locked loop. Finally, the frequency identification algorithm of the frequency locking loop is followed by the code loop in the case of carrier assistance.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN967.1

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