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The New Standard In Diver Communications
NASDive Brings More Clarity, Safety to Saturation Diver Communications


Benedict Grant

NASDive has the potential to create a step change in underwater communications for the saturation diving industry.
For more than 30 years, Nautronix (Aberdeen, Scotland) has designed, manufactured and provided communication systems to both the commercial and defense saturation diving markets. These are primarily wired systems to connect the dive bell to the DSV dive control, chambers to the DSV saturation control and numerous other communications points. In addition to the wired system, a wireless emergency through-water system is provided to link the dive bell to the DSV dive control.

Saturation divers breathe a heliox gas mixture which is modified in relation to diving depth. At deeper depths, this gas mixture can have a significantly higher percentage of helium than regular air. One result of this is to give divers a somewhat comical and difficult to understand 'Donald Duck' voice. This effect can render the diver uninterpretable to the untrained ear. Thus, for clarity of communication, saturation diving communication systems typically utilize a helium speech unscrambler. This reverses the effects of the helium and gives the divers their usual voice back. An effective helium speech unscrambler is essential for clear communications.

Industry Needs
In early 2012, Nautronix completed an investigation into the current capability of available diver communication systems. It was realized that there had been a lack of significant innovation in this market in recent years. It was highlighted that industry had a wish for improved clarity of speech to saturation divers, a system that is easier to use, and one that enables quicker fault finding to decrease dive downtime due to loss of communications.

Research was conducted into the various hardware and software architectures and platforms that could be utilized within a new system. A significant number of areas were identified that would enable a new generation of diver communications systems to be created that would exceed the expectations of industry.

A detailed technical specification was put together for such a system, and thus the development of the NASDive technology commenced. Two years on from the initial investigation, Nautronix is now delighted to announce the launch of this new system.

NASDive has been designed from the ground up to offer a completely new approach to diver communication. With its background architecture, touch-screen user interfaces and increased functionality, Nautronix believes this system will be the new benchmark product in the market.

Audio Quality
Traditional diver communication system architectures make use of low-level analog signals to communicate between the bell and dive control, and saturation chambers and saturation control. These signals are highly susceptible to the effects of noise pickup and electrical interference'which are detrimental to speech quality.

To address this, NASDive has moved to the fully digital domain. Speech is now digitized at source and transmitted using digital telemetry. Speech from the bell is digitized within an external pressure-rated electronics bottle, and passed to dive control over a single fiber (using Ethernet) or single twisted pair (using VDSL2).

Within the chambers (or any other location) speech is digitized at the communications station and passed to saturation control over Ethernet using standard Cat5 cabling.

This approach to the system architecture removes the low analog signals from all significant cable lengths, greatly improving the audio channel. Thus speech clarity is greatly improved'a fundamental step change for diving communication systems. To continue this article please click here.

Benedict Grant has been involved in the hydroacoustic sector of the oil and gas industry for approximately seven years. He graduated with a master's in electronic and electrical engineering in 2006. He currently holds the position of technology product manager with Nautronix. Within this role, he looks after the company's product research and development strategy.

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