gps导航工具包，可用于分析GPS误差，伪距及导航融合算法-This report include the review of • Principle of Radio Navigation: navigation base on trilateration has been investigated and the over determined Eq. for navigation has been solved. • GPS Ephemeris Data

三边测量定位，可以在matlab上进行仿真，值得相互借鉴学习。-Trilateration positioning, can be simulated in matlab, learn each other is worth learning.