Variability of available capacity due to the effects of depth and temperature in the underwater acoustic communication channel

Tumar

Schönwälder

2010

Oceans'10 Ieee Sydney

Self Cite

Abstract-Global climate change is a widely accepted phenomenon and it is well understood that it is also leading to changes in the oceanic conditions. Increased industrial activities have also led to anthropogenic ocean acidification, the effects of which, on marine ecosystems, is a vigorously investigated topic. However, the impact of these phenomenon on underwater acoustic communication has not been investigated thoroughly. Fluctuations in ambient ocean conditions, such as salinity, acidity and temperature can lead to changes in the underwater acoustic channel performance. Since both marine mammals and man-made underwater wireless networks depend upon acoustic communications it is important to understand the effects in this context as well. An insight into the effects of climate change and anthropogenic ocean acidification could aid in designing better communication systems and also help explain some observed changes in marine mammal communication behavior. In this paper we present the results of a study conducted to better understand the effects of global climate change. Along with a brief presentation of the mathematical model, results of increasing temperature and acidity are discussed and effects on digital and marine mammal communication are both explored.

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Effects of climate change and anthropogenic ocean acidification on underwater acoustic communications

Tumar

Schönwälder

2010

Oceans'10 Ieee Sydney

Self Cite

“…We utilize the equations presented by the authors of [6], [11] in order to perform the channel characterization in our simulator.…”

Section: Channel Characterization Modelmentioning

confidence: 99%

Modeling underwater acoustic communications for multi-robot missions in a robotics simulator

Cernea

Birk

2010

Oceans'10 Ieee Sydney

Self Cite

Abstract-Missions involving multiple Autonomous Underwater Vehicles (AUVs) are gaining increasing popularity with the advent of better control mechanisms and availability of acoustic modems that allow for cooperative networked tasks to be carried out by Unmanned Underwater Vehicles (UUVs). However, high costs associated with offshore testing and the lack of useful tools to accurately simulate multi-AUV tasks has been a hindrance to exploiting the full potential of the field. Even though there exist a few simulators for modeling a single AUV, there is virtually no simulation tool available that allows modeling of acoustically networked communications between multiple AUVs by accurately characterizing the underwater acoustic channel. In this paper we present an overview on modeling of the underwater acoustic channel, taking into account the high degree of local variability of ocean conditions, multi-path echoes and ambient noise, within the framework of an underwater acoustic communications server for the Unified System for Automation and Robotics Simulator (USARSim) robotics simulator.

“…Communication in the underwater acoustic channel imposes a dependence between achievable data-rate and the transmission distance, depth, frequency and transmission power [3,4]. From Figure 1 it becomes clear that using a multi-hop approach and preferring deeper routes provides greater reliability and transmission capacity.…”

Section: Research Questions and Proposed Approachmentioning

confidence: 99%

Adaptive Underwater Acoustic Communications

Mechanisms for Autonomous Management of Networks and Services

Schönwälder

2010

Self Cite

Abstract. Underwater wireless networks consist of mobile and static nodes, which usually communicate using the acoustic channel since radio transmissions attenuate rapidly and optical communication is only suitable for short distances. The underwater acoustic channel is plagued with issues of high transmission power requirements, rapidly changing channel characteristics, multi-path echoes, possible high ambient noise, high and varying propagation delays. To achieve optimal performance an underwater network must be able to sense its ambient environment and react by adapting its communication parameters. This paper proposes to take a two-tier approach in order to develop adaptive underwater communications; by developing an adaptive routing protocol that reacts to environmental parameters and developing a software acoustic modem to enable lower layer adaptations as well.