Distributed CDMA-based MAC Protocol for Underwater Sensor Networks

Abstract

Abstract-Underwater Sensor Networks are typically distributed in nature and the nodes communicate using acoustic waves over a wireless medium. Such networks are characterized by long and variable propagation delays, intermittent connectivity, limited bandwidth and low bit rates. Due to the wireless mode of communication between the sensor nodes, a Medium Access Control (MAC) protocol is required to coordinate access to the shared channel and enable efficient data communication. However, conventional terrestrial wireless network protocols that are based on RF technologies cannot be used underwater. In this paper, we propose PLAN -a MAC Protocol for Long-latency Access Networks that is designed for use in half-duplex underwater acoustic sensor networks. We utilize CDMA as the underlying multiple access technique, due to its resilience to multi-path and Doppler's effects prevalent in underwater environments, coupled with an RTS-CTS handshaking procedure prior to the actual data transmission. Using simulations, we study the performance and efficiency of the proposed MAC protocol in underwater acoustic networks.

A Delay Time Overlapping MAC Protocol for Underwater Wireless Sensor Networks

“…Additionally, research comparing performances of protocols that are used under water [7] was conducted, and various protocols that are formed by transformin g existing MAC protocols [8][9][10] were suggested.…”

Exploring random access and handshaking techniques in underwater wireless acoustic networks

“…The authors in this article focus their research on the optimal power control strategies in the physical layer. In [42], the authors utilize CDMA as the underlying multiple access technique. An RTS/CTS handshaking scheme is employed for every channel before actual data transmission.…”

Handling Triple Hidden Terminal Problems for Multichannel MAC in Long-Delay Underwater Sensor Networks

“…Strict synchronization among all nodes is needed in this scheme. In [22], the authors utilize CDMA as the multiple access technique. A RTS/CTS handshaking scheme is employed for every channel before actual data transmission.…”

“…Although many previous studies [14], [10], [18], [6], [21] focus on single-channel networks, the multichannel technology has been shown more promising [20], [13], [8], [27], [19], [22] in both terrestrial and underwater networks. Further, recent acoustic communication advances [11] make it possible to utilize multiple channels in underwater networks.…”