Triangle star identification is a mature algorithm in engineering

to overcome the low character dimensions and high percentage of redundant matches

proposed an improved star identification base on traditional triangle identification algorithm. The relative magnitude information of star pair is stable and taken as assistant character during identification process. Introduced the fourth star besides triangle stars

the accessorial angular distance between them could be supplementary character to reduce redundant

and also could be verification. Appropriate characters were chosen to decrease the capacity of guide star database. In order to decrease the time spent during star-pair matching

hashing search used. The simulation result demonstrated all these improved identification efficiency and identification time reduced.