The invention discloses a multi-
satellite direct positioning method based on
CUDA (Compute Unified Device Architecture) parallel calculation, relates to the field of space-based
electromagnetic signal positioning, and aims to be suitable for large-range and high-precision positioning of low-
signal-to-
noise-ratio signals. According to the technical key points, a positioning area is determined in a
satellite coverage range according to
prior information, and grid points are divided on the surface of the earth; two or more satellites with time-frequency synchronization obtain observed quantities of signals emitted by the same ground
radiation source, a first
signal model of the multiple observed quantities is constructed, and down-conversion is carried out on the first
signal to obtain a second signal; constructing a cost function by using signal characteristics (such as
time difference of arrival,
frequency difference of arrival and the like) in a
radiation source signal received by a
satellite; a cost function corresponding to each grid point is subjected to multi-core
parallel computing through the GPU; and summarizing results, and searching the maximum value of the cost function to determine the estimated position of the ground
radiation source. According to the multi-satellite direct positioning method based on the
CUDA, the characteristic that parallel calculation can be carried out when cost function grid searching optimization is carried out in direct positioning is utilized, calculation is directly carried out on satellites, satellite-ground
data transmission is omitted, the positioning time is shortened by utilizing the independence of searching calculation among grids, and the real-time performance of a
positioning system is guaranteed.