Low-Overhead Network Coding Communication for Wireless Multihop Networks

Abstract

For support of interactive multimedia applications in wireless multihop networks, a sequence of data messages are required to be transmitted simultaneously in both directions. Here, intermediate wireless nodes hold temporarily data messages in both directions with high probability. Network coding methods have been proposed for reduction of forwarding and end-to-end transmission delays and for increase of end-to-end data message throughput. However, for collision-free transmissions, all the 2-hop neighbor intermediate nodes are required to be suspended during a data message transmission. Some extended Request To Send/Clear To Send (RTS/CTS) controls have been proposed for network coding support; however, for avoidance of collisions between control messages, longer transmission delay is inevitable. This paper proposes a novel RTS/CTS control method for supporting network coding in bidirectional data message transmission. Here, the CTS and ACK control messages are transmitted with the usual Short Inter Frame Space (SIFS) interval and their correct simultaneous transmissions are detected by their collisions. In simulation experiments, 30.2% higher end-to-end throughput of data messages is achieved by the proposed RTS/CTS control in comparison with conventional methods.