中文摘要：

BI Yan-Zhong Ph.D. candidate at Institute of Software, Chinese Academy of Sciences. His research interests include routing and MAC techniques of wireless sensor networks.E-mail： yanzhong02@ios.cn. SUN Li-Min Professor at Institute of Software, Chinese Academy of Sciences. His research interests include wireless sensor networks and mobile IP networks. E-mail：sunlimin@ios.cn. ZHU Hong-Song Ph.D. candidate at Institute of Computing Technology, Chinese Academy of Sciences. His research interests include embedded systems and wireless networks. YAN Ting-Xin Master student at Institute of Software, Chinese Academy of Sciences. His research interests include routing and MAC techniques of wireless sensor networks. LUO Zheng-Jun Master student at Institute of Software, Chinese Academy of Sciences. His research interests include ultrasonic techniques and embedded systems.