【作者】 孙函子；

【导师】 胡辉；

【作者基本信息】 华东交通大学 ， 通信与信息系统， 2011， 硕士

【摘要】 高动态接收机指在接收信号有较高的多普勒频率及其一阶、二阶导数时仍能正常工作的接收机。本文针对高动态低信噪比环境下GPS接收机基带信号处理算法遇到的问题,重点研究了实时高动态基带信号处理模块的设计实现。本文主要进行如下几点研究工作:弱信号的捕获算法的设计。文章分析了相干捕获算法和非相干捕获算法的增益。文中采用相干与非相干相结合的捕获算法实现了输入信噪比为25dBHz信号的捕获,并提供了一种非相干累积时间的设计方案。伪码跟踪算法、关键参数和环路控制策略的设计。高动态环境下多普勒效应对伪码的影响不可忽略,文中重点分析了与高动态载波跟踪算法相匹配的、基于载波辅助技术的归一化带符号点积功率伪码跟踪算法,并提出了一种新的预检积分时间可变的伪码跟踪环控制策略。载波跟踪算法、关键参数和环路控制策略的设计。高动态GPS软件接收机基带信号处理算法的关键是载波跟踪算法的设计,文中重点研究了频率牵引算法,FLL与PLL复合环算法及载波跟踪环重要参数的设计。文中提出了一种新的分阶段载波跟踪环控制策略,兼顾了环路的动态性和精确性。本文采用SIMGEN-I10型模拟器模拟的高动态GPS卫星信号为实验对象,基于MATLAB与VC++软件平台实现上述高动态低信噪比下的GPS接收机基带信号处理算法,经实验证明,接收机可以在载体动态为最大加速度?1 00?g ?,最大加加速度?4 0?g /?s?的条件下稳定工作,结合后续的定位解算模块,接收机最终达到的定位精度达水平方向为15米,高度方向为20米,可以满足课题对定位精度的要求。更多还原

【Abstract】 The high dynamic receiver could still work normally when the received signal has the high Doppler frequency and in the first-order, the second time derivative。This article studies the designing and realization of the real-time high dynamic base band signal processing module according to the GPS receiver base band signal processing algorithm’s problems base on the high dynamic low signal-to-noise ratio environment, . This article mainly carries on the following several research work:Weak signal capture algorithm design. The article firstly analyzes and compares four kinds of capture algorithm’s characteristic, then has analyzed gain of the coherent capture algorithm and the non-coherent capture algorithm. The article has realized the input signal-to-noise ratio 25dBHz for the signal capture with coherent capture algorithm and non-coherent capture algorithm, and has provided one kind of non-coherent cumulative time design proposal.Pseudo-code track algorithm, key parameter and ring circuit control policy design. Under the high dynamic environment the Doppler effect influences the pseudo-code can not be neglected, the article analyzes Normalized belt mark dot product power pseudo-code track algorithm which matched with the high dynamic carrier track algorithm and based on the carrier auxiliary technology ,and proposed one kind of new pseudo-code track link control policy that preventive maintenance integration time is variable.Carrier track algorithm, key parameter and ring circuit control policy design. The high dynamic GPS software receiver base band signal processing algorithm’s key is the carrier track algorithm design, the article studies the frequency pulling algorithm, FLL and the PLL compound link algorithm and the carrier track link’s key parameter design. The article proposes one kind of new carrier track link control policy by stages, and has given dual attention to ring circuit’s dynamic and accuracy.This article uses the high dynamic GPS satellite signal which the simulator simulates for the experimental subject, realizing GPS receiver base band signal processing algorithm based on MATLAB and the VC++ software platform under the high dynamic low signal-to-noise ratio, proved after the experiment, the receiver can work steadily in the carrier tendency for the maximum speed, the maximum acceleration, the most acceleration, unifies the following localization resolving module, the pointing accuracy which the receiver achieves finally reaches the horizontal direction is 10 meters, the direction is 15 meters highly, can satisfy the topic request of the pointing accuracy.更多还原