Wang Ping was born in 1977. He received his B. S. degree in 2000 and M. S. degree in 2003 from Harbin Institute of Technology respectively. He is currently a Ph. D. student in Communication Research Center at Harbin Institute of Technology. His research interests are protocols of wireless networks. E-mail: blesswp@gmail.com Chen Bingcai was born in 1976. He received his B. S. degree in 1999 and M.S. degree in 2003 from Harbin Institute of Technology respectively. He is currently a Ph.D. student in Communication Research Center at Harbin Institute of Technology. His research interests are satellite mobile communication network and wireless communication system. Gu Xuemai was born in 1957. He is a professor of Communication Research Center at Harbin Institute of Technology. His current research interests are satellite communication system, mobile communication,deep space communication and digital trunking system. Liu Gongliang was born in 1979. He received his B. S. degree in 2001 and M. S. degree in 2003 from Harbin Institute of Technology respectively. He is currently a Ph. D. student in Communication Research Center at Harbin Institute of Technology. His research interests are multicast of satellite mobile communication.