Posted on 17.06.2011 - 12:00 EDT in SURVEY NEWS by Rons_ROV_Links
EvoLogics, a leading vendor of innovative solutions for underwater communication, was proud to supply EvoLogics S2C underwater acoustic modems to provide data transfers from multiple asynchronously operating ADCPs using a single pair of modems. These units were deployed in the West Pacific for the Northwestern Pacific Ocean Circulation and Climate Experiment.
In January 2011 an Institute of Oceanology, Chinese Academy of Sciences (IOCAS) research vessel, 'Kexue 1' ('Science One') returned from a 52 day cruise in the West Pacific. The IOCAS team, among other tasks, completed installing a mooring system that carries oceanographic instruments used in the Northwest Pacific Ocean Circulation and Climate Experiment (NPOCE).
Initiated by IOCAS, the NPOCE is an international cooperative program aimed at studying the dynamics of Northwest Pacific (NWP) circulation and defining its role in moderating both regional and global climate systems. Joined by scientists from eight countries, the NPOCE program addresses the lack of in-situ observations of the NWP circulation with the deployment of long-term moorings, Argo floats, the conduction of hydrographic surveys, etc.
The instruments, moored by the IOCAS team during the recent cruise, include two ADCPs that will collect valuable data about the Mindanao N. The ADCP-buoy Current (MC) and the Mindanao Undercurrent (MUC) at eight now floats c. 400m below the surface, the depth on location being over 6000m. The mooring system was designed and integrated by Laurel Technologies, a high-tech industrial company, offering products for geophysical and marine research.
EvoLogics provided the IOCAS with S2C (sweep spread carrier) underwater acoustic modems as an efficient solution for retrieving the collected ADCP information. Equipped with internal data loggers, both ADCPs are connected to a single acoustic modem for uploading the data to the surface.
Saving up scarce space, only one S2C modem is placed on the buoy. Fitted with an energy-preserving wake-up mode, the downside modem only turns itself on when detecting encoded acoustic requests from the topside modem. Both S2C modems support asynchronous data transfers with user-adjustable priorities when handling data streams from multiple sources. Once an acoustic connection is established, this key feature allows access to each ADCP individually, initiating data retrieval or requesting status information.
Laurel Technologies, the main dealer of EvoLogics' products in China, provided technical support for S2C modems during the IOCAS cruise.
IOCAS team reported successfully communicating to the ADCPs both immediately after deployment and upon return to the site ten days later. Data, collected during the ten day testing, was downloaded from each of the instruments. EvoLogics received positive feedback about the S2C modems' performance after the cruise was completed.
NPOCE (Northwestern Pacific Ocean Circulation and Climate Experiment) program is a multi-national, multi-institutional IOCAS (Institute Of Oceanology, Chinese Academy Of Sciences) initiative, focused on studying the Northwestern Pacific ocean circulation.