The invention discloses a large-scale
MIMO multi-
satellite positioning and direction
estimation method and
system based on angle information. The method comprises the following steps: firstly, obtaining channel
matrix estimation between each
satellite and a user by sending a
pilot signal; then, obtaining estimated values of channel parameters by using a
tensor-ESPRIT
algorithm, wherein the estimated values comprise an
angle of departure and an
angle of arrival; according to the estimated departure angles, direction vectors between the user and all satellites are obtained, an
optimization problem on spherical manifold is established, altitude constraints are considered, and a Riemann
conjugate gradient method is used for solving and obtaining a user position
estimation value; and finally, according to the estimated user position and arrival angle, establishing an
optimization problem on the SO (3) manifold, and solving by using a Riemannian
gradient descent method to obtain an estimated value of a user array
rotation matrix. According to the method, positioning and direction
estimation are performed by combining channel information between a plurality of satellites and users, and altitude constraints are considered during positioning, so that compared with single-
satellite and non-constraint conditions, the positioning performance can be remarkably improved, and meanwhile, the method has good direction estimation performance.