Corresponding author. Tel: + 86-25-84892304-855. E-mail address : dbqr@ 163. comMiao Jianfeng Born in 1981 ,he received B. S. degree from Nanjing University of Aeronautics and Astronautics(NUAA) in 2004, and then became a Ph. D. candidate under the joint supervision Ph. D. scheme of NUAA and Hong Kong Polytechnic University. His main research interests are GPS software receiver and navigation system.