develogic - Digital Underwater Communication – HydroAcoustic Modem Ham.Node

develogic specialises in the design and manufacturing of integrated solutions – i.e. software, electronics and mechanical components – dedicated to naval, offshore and oceanographic applications. Our product range comprises wireless underwater communication systems (HAM.NODE), underwater signal transmission simulators (UWAST-S), releaser units, advanced pressure housings and broadband power amplifiers for ultrasound applications.

Based on our long-lasting expertise in both software and hardware engineering with focus on complex signal processing applications, we are a reliable partner for providing you with state-of-the-art solutions tailored to your individual requirements. Please visit our web page for more detailed information, or contact us at the address below.

HAM.NODE – DIGITAL HYDROACOUSTIC MODEM WITH MULTI-NODE CAPABILITY

Our modular hydroacoustic modem HAM.NODE represents the core component for scalable communication systems, satisfying high demands on digital wireless underwater communication. Due to its highly modular design, HAM.NODE is a multi-purpose wireless underwater communication solution, adjustable to most environmental conditions and mission scenarios.

HAM.NODE's powerful acoustic communication is based upon an optimised OFDM-MDPSK modulation scheme with decision feedback equalising. For transmission channels with complex multi-path characteristics, such as long-range shallow water communication, an additional MFSK modulation scheme is available.

This, combined with correction of Doppler shift, advanced convolutional error correction coding and an adaptive transmission protocol, enables reliable communication at high transmission rates, even under the most challenging transmission conditions.

Highly flexible multi-channel transmission allows for adaptation of the communication parameters to the environmental conditions, e.g., to shallow water horizontal channels with difficult multi-path conditions (echos), as well as deep vertical channels.

HAM.NODE's key features include:

• Advanced Phase-Shift Keying (OFDM-MDPSK with DF) or Frequency-Shift Keying (MFSK) with flexible parameterisation
• Direct drive connection to most transducers is possible, providing operability with a wide range of carrier band frequencies
• Low power consumption in sleep/listening modes (<1mW / <30mW) paired with configurable transmitting power of up to 500W (30W to 80W typical)
• Flexible supply voltage from 9V to 36V for easy integration into existing systems
• Various functional options, modular electronic and mechanic design
• Broad range of modular pressure housings

HAM.NODE can be configured to realise both very reliable long-range signal transmissions as well as very high data transmission rates in close-up range. In general, transmission data rates depend on the operating environment and transducer selection. A typical net data rate achieved in unidirectional streaming mode with low cost ITC3013 transducers across 2000m in deep water was >5kbit/s. Ranges up to 28,000m were realised with ITC2002a transducers.

UWAST-S – UNDERWATER ACOUSTIC SIGNAL TRANSMISSION SIMULATOR

UWAST-S is an advanced, integrated system for simulating the acoustic wave propagation of complex underwater channels in real-time, thus providing powerful test conditions for efficient and cost-effective development and testing of systems with integrated acoustic communication solutions.

The following examples illustrate typical applications of UWAST-S:

• Investigation of the impact of multi-path propagation, Doppler-shift, noise sources, etc. on signal transmission
• Hardware / software adoption to time-variant channel conditions
• Development and testing of signal-processing algorithms
• Simulation and testing of the impact of transducer directivity
• Convenient hardware testing in an in-situ-like environment

UWAST-S modifies the input signal according to configurable channel specifications – either based on static parameterisation or dynamic variation of transmission characteristics.

The complexity of real-time simulation scenarios is only limited by computing power of the simulator workstation. The optional file-based simulation mode also allows for offline investigation of very complex multi-path situations.

UWAST-S is available in various stages of expansion – up to a complete simulation solution, including all necessary software and hardware, such as acoustically damped water test tanks and hydrophones.

ADVANCED EQUIPMENT FOR OFFSHORE AND SIGNAL PROCESSING APPLICATIONS

Besides our communication and simulation solutions HAM.NODE and UWAST-S we offer further specialised devices dedicated to naval, offshore and oceanographic applications, as well as signal-processing applications.

Please visit our website for more detailed information on the following products:

• Acoustically triggered releaser units
• Advanced pressure housings for underwater applications: lightweight, corrosion resistant, with state-of-the-art serviceability
• Broadband power amplifiers for ultrasound applications, e.g., for use with acoustic transducers