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

东北农业大学：《精细农业》课程教学资源（PPT课件）第二章 GPS（全球定位系统及其应用）

第一节GPS定位系统的兴起及其特点 GPS是1973年由美国国防部(DOD)开始建立目的是用于美国军队的定位、导 航、武器制导等。经历了4个阶段:理论研究阶段;建设阶段;建成运行阶段;更新阶段

第一章概论 第一节GPS的兴起与特点 一、GPS的建立 1973年由美国国防部(DOD)开始建立,称为全球定位系统 global positioning system,目的是用于美国军队的定位、导航、武器制导等。拟定由21+3颗卫星组成。到今天为止经历了4个阶段:

Styles of kinematic GPS Kinematic GPS techniques go by a number of names with features that are often receiver specific Kinematic GPS: Early term which implies that there is no loss of lock while the receiver is moving. In survey mode, if loss of ock occurs the antenna must be returned to a point of know ocation

全新的设计 TPS1000经纬仪定位系统是徕卡公司一个全新的系列仪器设计新穎·既保持 了传统的风格,又有新的特点功能优异·性能突出新系列共分四部分:

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)

Rank deficiencies Ranks deficiencies are combinations of parameters that can not be separately estimated In GPs. there are several rank deficiencies UTl, Longitudes of all the stations and the nodes of the satellite orbits, effectively can not be separated In theory, orbit perturbations by the moon/sun on the GPs

Mathematical models in GPS Review assignment dates (updated on class web page) Paper draft due Mon April 29 Homework 3 due Fri May 03 -Final class is Wed May 15. Oral presentations o papers. Each presentation should be 15-20 minutes, with additional time for questions. · Next three lectures:

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)