Transport of Underwater Sensor Data

A sensor has data to send to a human observer. In the present case the sensor is a camera, and the data consists of an image. When commanded to do so, the image is heavily compressed, passed to the modem, and sent by robust, low data rate acommsgateway, then to the observer. The sensor system retains the uncompressed image in a file. If the observer finds the (compressed/decompressed) image to be of interest, an AUV (EMATT) is directed to move to the near vicinity of the sensor, and command anacoustic upload of the original image file. The vehicle then physically returns to the vicinity of the gateway, and responds to a command to upload its data. It is anticipated that the upload processes will use high speed data links. The Phase 1 effort identified four areas requiring analysis or development to support the concept:1. Identify significant features of targets and clutter objects which appeal to human identification.2. Define algorithmic approaches to extract those features into an image which can be compressed for acoustic transmission. Prototype one approach and demonstrate performance with a recorded image.3. Evaluate alternative methods permitting very shallow water operations with EMATT, to include depth control and vectoring.4. Determine and implement modem protocols to enable data uplink. There are three related items with which we are familiar: the ONR AOFNC program, the ONR Very Shallow Water/Surf Zone MCM program, and the ONR/SPAWAR Telesonar/DADS program. The AOFNC is run by Dr. Tom Curtin, as is this proposed Data Truck STTR.Benthos, under subcontract to Sippican for the AOFNC, is tasked to develop an underwater GPS for geo-positioning of multiple undersea vehicles. This project will use the ATM 88x family of modems to transmit and receive the underwater signals. The MUSBLdescribed here and in the Phase One Final Report is a different form of positioning/navigation system, but both could be available in one modem, and could share many of the same algorithms and hardware resources. Furthermore, some of the upgrades plannedfor EMATT under this proposal will benefit the AOFNC effort, especially with regard to the ability to provide acoustic C2, depth control.The image processing efforts are especially important to the CSS crawler developments for MCM, and, indeed, much of the MCM money available for image processing has been targeted as matching funds for this STTR program. Finally, the proposed enhancementsto the Benthos high speed modem will directly benefit the Telesonar/DADS program by providing high data rate transfer of large volumes of data, when such is found to be necessary. We also believe the core data truck will be highly effective as a collectorof data in a dense network of sensors and modems, such as DADS.