Triangle star identification algorithm is widely used in attitude determination system

that adopts star sensor as navigation parts at present. But low characteristic dimensions lead to high percentage of redundancy and mistake. To improve accuracy of triangle identification algorithm

a modified algorithm which based on traditional one is proposed. Record the star pairs that meet interstellar angle threshold in star matrix

and count the guide star’s appearance simultaneously

according to the truth that each star must be attached to two sides of the triangle

eliminate the entire star pair which any particular star appears less than two times

then construct guide triangle from stars left in star matrix. Only take interstellar angle and relative magnitude of stars as pattern

decreases the capacity of the database

enhances the validity of results

for another thing

hashing search method used during star identification speeds up the identification process.