Outline Review u Examined basics of GPS signal structure and how gnal is tracked a Looked at methods used to acquire satellites and start g Today we look at

1. Basic Knowledge of GPS In 1973, DOd organized a Joint P Office (JPO) located at the U.S. Air Force Systems Command's Space The s Second Lecture Division, Los Angeles Air Force Base(AFB)to what?

1. Errors related to GPs Satellites 2. Errors related to GPS signal propagation in atmosphere 3. Error related to gPs receivers Gv Principles of the Global Positioning System

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

采用线性极化技术对几种不同用途的耐海水腐蚀低合金新钢种进行了测量和评选。讨论了化学成分、工艺因素和热处理条件对腐蚀性能的影响。线性极化技术的测量结果与外海掛片数据有更好的相关性。试验结果表明,局部腐蚀指数δ可以作为定性评定低合金钢/海水体系局部腐蚀性能的一种方法

一.天球坐标系空间固定的坐标系,该坐标系与地球自转无关,对描述卫星的运行位置和状态极其方便。 二.地球坐标系 与地球体相固联的坐标系统,该系统对表达地面观测站的位置和处理GPS观测数据尤为方坐标系统是由坐标原点位置、坐标轴指向和尺度所定义的

1.历史、发展和当前状况 2.坐标系统与时间系统 3.卫星轨道运动及GPS卫星的坐标计算 4.GPS卫星信号与传播 5.GPS观测量、观测方程及误差分析 6.绝对(单点)定位原理

1.1 Terminology Definitions 3. Point Positioning ys. Relative positioning The coordinates of a single point are determined when 1. Code Range vs, Carrier Phase Code measurements(meter level) Carrier phase measurements(millimeter range). Single point positioning

This is a Geodetic Control Test Field located at L Radial Surveying( Cartwheel): Madison County, Central Ohio. lial Surveys: one receiver at a fixed 2 Madison County High Altitude Test Range site, and measuring lines from this fixed

1.1 Physical Fundamentals This attenuation is usually expressed in decibels (dB). By definition, an attenuation of n dB means signal propagation from the that the original field strength is decreased by ite to the user by means of factor of 10-0In electromagnetic waves. Such waves Physical quantities