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Naval Research Laboratory - Development of a pre-programmed, untethered, 

 low drag submersible designed initially for scientific data collection. 

 Ultimate vehicle capabilities include a 6,000m (20,000 ft) depth capability; 

 a precise navigation capability combining inertial navigation with OMEGA 

 or doppler sonar; on-board data processing capability, pattern recognition 

 and artificial intelligence and a mechanical manipulator. 



Heriot Watt University - Development (over a 5 year period) of an untethered 

 vehicle which will operate from a tethered vehicle at a depth to be 

 specified. TV signals (1 picture/second), command/control functions, and 

 other data will be transmitted from the untethered vehicle, ROVER, to the 

 tethered vehicle, ANGUS 003, thru-water. 



CNEXO - Have developed and are now testing EPAULARD, a 6,000m depth-capable, 

 untethered vehicle designed to conduct exploratory missions of the ocean 

 floor. The vehicle operates in a pre-programmed mode and stores data 

 (photographs and echo-soundings) for surface processing. 



In support of untethered vehicle technology, the Departments of Ocean Engineering 

 and Electrical Engineering of the Massachusetts Institute of Technology are 

 conducting research into underwater communication systems for untethered vehicles 

 and submerged sensors. The program began in July 1978 and is headed by 

 Dr. Arthur B. Baggeroer. The following program description has been extracted 

 from Dr. Baggeroer ' s proposal to the MIT Sea Grant Program which is the major 

 funder of this research. 



"The overall goal of the research is to build an underwater communi- 

 cation system which implements the results of modern communication 

 theory using micro-processors. It will operate as a 'modem' providing 

 data transmission at the highest rate consistent with the operating 

 environment. In this way it should be able to serve a diverse number 

 of needs. The system is intended primarily for use with near vertical 

 paths, and it should be able to work at medium rates (>1 kbit/sec) 

 at long ranges ( > 3 km) and at high data rates ( > 10 kbit/sec) 

 at short ranges ( < .5 km) . It should also be able to respond flexibly 

 to changes in the operating environment by modifying the data encoding, 

 the frequency, and power level of the transmitters. 



Four separate topics on modern communication theory will be investi- 

 gated for possible implementation. 

 i) compression of data from sources using algorithms from speech 



and image processing, 

 ii) block and convolutional encoding procedures, 

 iii) adaptive array processing methods for improvided directivity 



to reduce required power levels and reverberation, 

 iv) use of a receiving station on a cable link employing fibre 



optics. 



In the first year of the program the following system components 

 will be designed: data source, encoding and modulation, transmitter, 

 channel, receiver, demodulation and decoding and data user. This 

 work includes specifying the algorithms and simulating them on a 

 general purpose computer to test their effectiveness before committing 

 them to a hardware design. The algorithms will also be "sized" 



