Hierarchical Code Assignment Algorithm and StateBased CDMA Protocol for UWSN  

作　　者：DU Xiujuan PENG Chunyan LIU Xiuxiu LIU Yuchi 

机构地区：[1]School of Computer Science,Qinghai Normal University

出　　处：《China Communications》2015年第3期50-61,共12页中国通信（英文版）

基　　金：supported by the Program for New Century Excellent Talents in University of China(NCET-11-1025);the NationalNatural Science Foundation of China(No.61162003,61163050,6126104);Qinghai office of science and technology(grant No.2012-Z-902);the Natural Science Foundation of Tianjin(No.10JCYBJC00600)

摘　　要：The characteristics of underwater acoustic channel such as long propagation delay and low bit rate cause the MAC(Medium Access Control) protocols designed for radio channels to be either inapplicable,or have low efficiency for UWSN(Underwater Sensor Network).We propose a hierarchical and distributed code assignment algorithm based on divisive probability function which can avoid conflict between spread codes with high probability,and provide a statebased MAC protocol for UWSN.Without RTS/CTS(Request To Send/Clear To Send) handshaking,each node maintains a neighbor table including state field,and packages are forwarded according to the state of the receiver,so it can avoid the interference caused by transmitting to a sending node in a half-duplex system and improve channel utilization.The design of power control minimizes the nearfar effect inherent in CDMA.Simulation results reveal that state-based CDMA protocol shows outstanding performance in throughput,delivery ratio and resource-consumption.The characteristics of underwater acoustic channel such as long propagation delay and low bit rate cause the MAC（Medium Access Control） protocols designed for radio channels to be either inapplicable,or have low efficiency for UWSN（Underwater Sensor Network）.We propose a hierarchical and distributed code assignment algorithm based on divisive probability function which can avoid conflict between spread codes with high probability,and provide a statebased MAC protocol for UWSN.Without RTS/CTS（Request To Send/Clear To Send） handshaking,each node maintains a neighbor table including state field,and packages are forwarded according to the state of the receiver,so it can avoid the interference caused by transmitting to a sending node in a half-duplex system and improve channel utilization.The design of power control minimizes the nearfar effect inherent in CDMA.Simulation results reveal that state-based CDMA protocol shows outstanding performance in throughput,delivery ratio and resource-consumption.

关 键 词：UWSN CDMA MAC code assignment 

分 类 号：TN929.533[电子电信—通信与信息系统]