Upgrading Design and Simulation Research of MACA Based on the Underwater Acoustic Networks

摘要

Combining with the characteristics of Underwater Acoustic (UWA) channel, this paper puts forward an improved MACA protocol. Based on the Multiple Access with Collision Avoidance (MACA) used for wireless communication networks, we review MACA with some related literatures at first and then analyze and improve the performances of MACA respectively from three aspects including presenting an effective strategy to solve the problem of collisions among control packets, reasonably making use of the retransmission times and making a simple modification to the state transition rules of MACA. Finally, under the circumstance of the underwater acoustic environment and by use of the simulation tool—OPNET, we separately simulate our proposed MACA and the original MACA introduced or modified in the former research. The simulation results show that compared to the original MACA, our proposed MACA could not only steadily maintains the performance in throughput but also dramatically reduces the packet loss rate. Moreover, our improved MACA distinctly decreases the average end-to-end time delay of data packets as well as remarkably lowers the average energy consumption for transmitting data packets. Therefore, it provides certain reference values for the design of the MAC protocol for Underwater Acoustic Networks (UAN).