QoS-enabled underwater acoustic communications

For enabling efficient operation of untethered underwater vehicles, error-free underwater communication of command-and-control and telemetry data is a necessity. In contrast, the communication requirements for the sensor data of these vehicles are often less stringent, i.e., a few bad pixels in a SONAR image might be tolerated. To maximize...

Software-Defined Underwater Acoustic Modems Historical Review and the NILUS Approach

Flexible/adaptive acoustic modems that are reprogrammable/reconfigurable at all layers of the communication stack, either by a user or by means of autonomous decisions, are considered as an important enabler for interoperability and cognitive networking in the underwater domain. In this paper, we review the existing literature on software...

Sonar Waveforms for Reverberation Rejection, Part II: Experimental results

The influence of the waveform of the transmitted signal on the signal to reverberation ratio of a moving sonar array is analysed on an experimental basis. Experiments were conducted during sea-trials in shallow water areas in September 98 and October 99. The aim of the trials was to compare the performance of three waveforms: frequency modulated...

Flow noise analysis of towed sonar arrays

In the design of towed array sonar the reduction of flow noise is an important issue. In this paper flow noise theory and several methods to analyse flow noise are presented. These methods are applied to sea trial data of an experimental triplet array. The obtained results agree very well with accepted theory. It appears that the methods in...