Inertial Positioning System Additional Gravity Space Parameters

Missile weapon operating need many kinds of spatial parameters provided by surveying. The existing inertial positioning system(IPS) equipments can only provide geometric spatial parameters (longitude; latitude; elevation), but gravimetric spatial parameters (deflection of the vertical; height anomaly; gravity anomaly).In this paper, a rapid approximate applied model of computing deflection of the vertical and height anomaly is given, it make use of gravity field model of the earth, and digital elevation model (DEM) data, and the known deflection of the vertical and height anomaly in operating area, we discuss the method of rapid calculating of deflection of the vertical and height anomaly in operating area. By annexing this method to existing IPS equipment, it helps the IPS equipment to realize integrated positioning that missile operating required.The main contents are as follows:a. Analyzing the influence of deflection of the vertical on precision of missile targeting;b. Approximate computing of deflection of the vertical with gravity field model of the earth;c. Approximate computing of deflection of the vertical with DEM data;d. Data interpolation based on the known deflection of the vertical. According to this method, we calculated a lot of data for a certain area,and the conclusion is: Computing deflection of the vertical and height anomaly according to the method of "Approximate computing with gravity field model and DEM data + interpolating of polyhedral function" , the calculating result of this two parameters completely meet the requirements of missile operating, whether computing precision or computing speed.