Specific common processes White-noise: Autocorrelation is Dirac-delta function; PSD is flat; integral of power under PSD is variance of process(true in general) First-order Gauss-Markov process (one of most models common in Kalman filtering)

Statistical approach to estimation Examine the multivariate Gaussian distribution: (x-)\v-(x-) Multivariant f(x)= Minimize (x-u)'v(x-u) gives largest probability density By minimizing the argument of the exponential in the probability density function, we maximize the likelihood of the estimates(MLE)

Summary · Review: -Examined definitions of pseudorange and carrier phase Looked at some actual raw measurements from a RINEX file Today we look at:

Today's Lecture Examine specifics of GPS signals Multiple modulations on same carrier signal Structure of signals GPS receiver operation and satellite acquistion

Treat the basic description and dynamics of satellite orbits Major perturbations on GPS satellite orbits · Sources of orbit information: -SP3 format from the International GPS service Broadcast ephemeris message

Gravitational potential In spherical coordinates: need to solve

Class expectations This is a graduate level class. There is no final exam Grading in the class is based on homework (75%) and on a final written report(25%) The report will be revised during semester and should be 2000-3000 words(8-10 double spaced pages)

一、GPS的定义及历史 1.定义全球定位系统GPS( Global Position System),是一种可以授时和测距的空间交会定点的导航系统,可向全球用户提供连续、实时、高精度的三维位置,三维速度和时间信息

概述 GPS是英文 Navigation Satellite Timing and Ranging G| obal Positioning System的缩写,意为利用卫星导航进行 测时和测距,以构成全球卫星定位系统。是美国国防部主要 为满足军事部门对海上、陆地和空中设施进行髙精度导航 和定位的需要而建立的。自1973年美国军方批准成立联合 计划局开始GPS的研究工作到1993年系统建成该工程历时 20年,耗资300亿美元,成为继阿波罗登月计划和航天飞 机计划之后的第三项庞大空间计划。它从根本上解决了人 类在地球上的导航和定位问题,在军事和工农业等领域得 到了广泛的应用。给导航和定位技术带来了巨大的变化

一、GPS的定义及历史 1.定义 全球定位系统GPS(Global Positioning System),是一种可以授时和测距的空间交会定 点的导航系统,可向全球用户提供连续、实时、 高精度的三维位置,三维速度和时间信息