A NEW METHOD FOR CONSTRUCTINBG DOP OF SATELLITE NAVIGATION SYSTEM
一种构造卫星导航系统精度衰减因子的新方法

Positioning accuracy is closely linked to the dilution of precision (DOP). DOP reflects the geometric distribution of visible satellites in space and enlarges the ranging errors. The new estimations of GDOP, PDOP and HDOP called essential DOP are studied and their properies are discussed. The new defined DOP are determined by the maximum eigenvalue of the corresponding co-factor matrix.