1卫星在空间绕地球运行时,除了受地球重力场的引 力作用外,还受到太阳、月亮和其它天体的引力影 响,以及太阳光压、大气阻力和地球潮汐力等因素 影响 口若假设地球引力场的影响为1,其它引力场的影响均小于 105

GPS定位的基本观测量是观测站(用户接收天线)至 GPS卫星(信号发射天线)的距离(或称信号传播路 径),它是通过测定卫星信号在该路径上的传播时间 (时间延迟)或测定卫星载波信号相位在该路径上的 变化周数(相位延迟)来导出的

一、单基线平差模型 二、模型简单、易于编程实现 三、基线之间相关性被忽略 四、不易发现粗差

一、GPS现代化 二、GPS增强系统 三、GPS的应用 四、GPS高程问题

一、GPS高程问题 二、复习

Fundamental knowledg Quick Overview Kelperian 3 Laws First Law: ellipse, Sun is a focus Second law: the same area in same time Earth

GPS Basic Positioning Principle Two reference systems: Time and Coordinate Syst

3. Reference Systems Book: p 25-38 Dr Guoqing Zhou 1.1 Overview 1.2 A Group of Basic Ce GPS Basic Positioning Principle

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

Perigee and Apogee: The point of closest approach of the satellite with respect to the earth's center of mass is called perigee and the most distant position is the apogee. Nodes: The intersection between the equatorial and the nit sphere is termed the nodes, where the ascending node defines the northward