Location Method and Error Analysis for Three-Star Time-Difference System Using Digital Map

Aiming at three stars used to locate the ground radiant point, a precise location model using digital map and WGS-84 coordinate is presented, and an iterative location algorithm for ground target is therefore proposed. The location simulation is made by using simulated three-dimensional relief map, and the theoretical error expression for the location method is deduced, The presented result shows the location simulation is consistent with the error theoretical analysis, and the location error caused by height hypothesis can be effectively decreased.