高动态GPS接收机理论及数据处理方法研究

Due to GPS have precision 3-D continuous navigation and positioning capability for worldwide and all-weather, well anti-interference and secure, it has been applied to military field and military benefit has been given bring to by GPS. The high dynamic situation(for example,missile control and guide ) is a important field for GPS application. GPS receiver received reliably GPS signal that is in more difficulty in high dynamic situation than static and middle low dynamic situation. A general GPS receiver with general PLL (Phase locked loop) and DLL(Delay Locked Loop) could not worked in high dynamic situation under not INS velocity assitant. A design idea is present for high dynamic digital GPS receiver based on DSP. Mathematical molding of the digital PRN code acquisition and tracking system is established by accurately tracking the PRN coded phase of the GPS signal using digital delay lock loop(DDLL). The closed-form expressions are derived for the detection and false-alarm probablilties of the acquisition process. The linear and nonlinear performance analysis of DDLL is done for optimizing the receiver structures and paparmeters with tradeoff between the tracking errors due to receiver dynamic and due to input noise. A digital phase-locked loop(DPLL) is quantitatively investigated. The following performance of the first, second, and third-order DPLLs is analyzed mathematically：(1)loop stability and transient process; (2)steady-state probability density function (pdf), mean and variance of phase tracking errors; (3) carrier phase acquisition performance; (4)mean to the first cycle-sliping. The analysis of dependency of the tracking error on system dynamics, input noise and receiver design parameters provides with an important reference in designing the carrier sysnchronization system for high accuracy GPS positioning. An estimator structure based on the maximum likelihood estimation(MLE) of code delay and Doppler frequency has been analyzed for GPS application. At last, the scheme of high dynamic digital GPS receiver based on DSP has been given, band pass sampling is used in the front end design,differential least quare(DLS) , multi-stage signal parameter estimator and wavelets have been used for digital process. The investigative conclusion will be used for the design of high dynamic GPS hardware receiver

GPS系统在高动态环境中的应用具有重要的军事应用价值。与静态、中低动态环境相比，高肪扯越邮栈煽拷邮誈PS信号带来了较大的技术难度。首次将软件无线电的理论与方法应用于高动态GPS接收机的前端处理部分。采用差分最小均方方法、多参量的多级估计技术靶〔ū浠唤惺荽恚佣銮縂PS接收机的动态跟踪性能。