A Collision-Free Hybrid MAC Protocol Based on Pipeline Parallel Transmission for Distributed Multi-Channel Underwater Acoustic Networks

Jun Zhang,Gengxin Ning,Yan Xiong,Zhi Hu

doi:10.3390/electronics9040679

Abstract

The transmission rate between two nodes is usually very low in underwater acoustic networks due to the low available bandwidth of underwater acoustic channels. Therefore, increasing the transmission parallelism among network nodes is one of the most effective ways to improve the performance of underwater acoustic networks. In this paper, we propose a new collision-free hybrid medium access control (MAC) protocol for distributed multi-channel underwater acoustic networks. In the proposed protocol, handshaking and data transmission are implemented as a pipeline on multiple acoustic channels. Handshaking is implemented using the time division multiple access (TDMA) technique in a dedicated control channel, which can support multiple successful handshakes in a transmission cycle and avoid collision in the cost of additional delay. Data packets are transmitted in one or multiple data channels, where an algorithm for optimizing the transmission schedule according to the inter-nodal propagation delays is proposed to achieve collision-free parallel data transmission. Replication computation technique, which is usually used in parallel computation to reduce the requirement of communication or execution time, is used in the data packet scheduling to reduce communication overhead in distributed environments. Simulation results show that the proposed protocol outperforms the slotted floor acquisition multiple access (SFAMA), reverse opportunistic packet appending (ROPA), and distributed scheduling based concurrent transmission (DSCT) protocols in throughput, packet delivery rate, and average energy consumption in the price of larger end-to-end delay introduced by TDMA based handshaking.

Highlights

Underwater wireless communication and networking have attracted considerable attentions in recent years [1,2,3]
The third is the multi-channel parallel transmission opportunity, where the sources and destinations can communicate using multiple parallel channels created by code division multiple access (CDMA) [4] or frequency division multiple access (FDMA) [5]
We propose a new collision-free hybrid medium access control (MAC) protocol based on pipeline parallel transmission for distributed multi-channel underwater acoustic networks

Summary

Introduction

Underwater wireless communication and networking have attracted considerable attentions in recent years [1,2,3]. They are widely needed in the applications of marine research, oceanography, marine commercial exploitation, mine reconnaissance, tsunami warning, offshore oil industry, defense, etc. Underwater acoustic channels, which are characterized by limited bandwidth, high and variable propagation delay, time-varying multi-path and fading, and large. The first is the time domain parallel transmission opportunity which is caused by the large propagation delay among network nodes. Because the links in the underwater acoustic network usually have large and different delays, multiple packets can be transmitted and propagate in the same channel without interfering with each other at their receivers if their transmission time is carefully scheduled. The third is the multi-channel parallel transmission opportunity, where the sources and destinations can communicate using multiple parallel channels created by code division multiple access (CDMA) [4] or frequency division multiple access (FDMA) [5]

Results

Discussion

Conclusion