REF TEK is the supplier to the University of California, San Diego for the IDA program, which is a major portion of the IRIS/GSN program.
REF TEK started supplying digital telemetry for seismic applications in 1981, when it was approached by UCSD to supply digital telemetry for the ANZA Network, the first such network in the USA. Since then, REF TEK has been supplying error-corrected digital telemetry for regional and national networks for research and public safety purposes worldwide. Until very recently, REF TEK has been the only commercial supplier of error-corrected digital telemetry. Now most investigators understand the problems introduced in processing by bit errors, including finding automatic phase picks.
The Southern Great Basin Seismic Network (SGBSN) is a large 42 station network that monitors seismicity around the Yucca Mountain, Nevada large nuclear waste disposal area. It is operated by the University of Nevada, Reno. The geometrical concept for this network has been to deploy radio telemetry subnets with nodes (or hubs) that then forward the data to Reno via microwave. At Reno, the acquisition and processing is accomplished on SPARC workstations. Originally, when part of the network was first deployed by the US Geological Survey, the nodes transmitted via satellite (VSAT) to the USGS National Earthquake Information Center in Golden, Colorado. This network emphasizes three relevant aspects: the hub concept, the use of a UNIX workstation in communication and acquisition, and satellite communication.
The Geological Survey of Japan (GSJ) Network is a 16-station network deployed around the Kobe area to record aftershock seismicity. The communication vehicle is ISDN digital lines, and the processing is on UNIX workstations. Although, this network uses computer interfaces with REF TEK DAS units, it nevertheless demonstrates the use of REF TEK instruments with links other than narrow band, voice-grade phone lines or radios and the use of workstations for communication and acquisition.
The table below is a list of digital telemetry networks supplied by REF TEK.
REF TEK’s innovation in network technology, the Advanced Seismic Networks approach, offers customers telemetry stations and networks for a variety of communications media including IP networks, satellite and radio telemetry, analog and digital lines. The two most recent installations in Table 1 utilize the Advanced Seismic Networks approach.
Digital Telemetry Networks Supplied By REF TEK
|Date||Description of Network||Organization Operating Network||Communication Media|
|1981||ANZA Network||University of California, San Diego, Scripps Institution||UHF, Microwave|
|1983||Four networks in Italy||ISMES, Bergamo||UHF|
|1985||Parkfield High Frequency Array||University of California, Berkeley||UHF|
|1986||Portable Telemetry Array||University of California, Lawrence Livermore Laboratory||UHF|
|1987||Parkfield Early Warning Network||US Geological Survey, Menlo Park||UHF|
|1987||The Geysers Network||University of California, Lawrence Berkeley Laboratory/US Geological Survey||UHF|
|1987||Parkfield Differential Ground Motion Array||US Geological Survey, Menlo Park||Cable Telemetry|
|1988||Perry Nuclear Power Plant Network||Cleveland Electric Illuminating||UHF|
|1988||IDA (International Deployment of Accelerometers)||University of California, San Diego, Scripps Institution||Global Dial-up|
|1989||SMU Deployable Array||Southern Methodist University||UHF|
|1990||Kyrgyz Telemetry Network||US/Russia Joint Seismic Program||UHF (now upgraded to spread spectrum radio)|
|1990||Kyrgyz Dense Telemetered Array||US/Russia Joint Seismic Program||UHF (now upgraded to spread spectrum radio)|
|1992||Southern Great Basin Network||University of Nevada, Reno||UHF, VSAT|
|1994||Virginia Network||Virginia Polytechnic Institute (Virginia Tech)||UHF|
|1994||Nuevo Cuyo Network||INPRES, Argentina||VHF/UHF, dial-up|
|1995||Southern Great Basin Network||University of Nevada, Reno (additional stations)||UHF, VSAT|
|1995||Chile Network||University of Chile||UHF|
|1996||Kuwait National Network||Kuwait Institute for Scientific Research (KISR)||UHF|
|1996||Nor-Oeste Argentino||INPRES, Argentina||VHF/UHF, dial-up|
|1996||Kobe Network||Geological Survey of Japan||ISDN|
|1997||Friuli Network||Instituto Nazionale de Geofisico/Civil Protection, Italy||Dial-up|
|1997||Thailand National Telemetry Network||Thailand Meteorological Dept.||VSAT, Dial-up|
|1997||Kobe Network||Geological Survey of Japan (expansion)||ISDN|
|1997||San Calixto, Bolivia Network||San Calixto Observatory||UHF|
|1998||Puerto Rico National Telemetry Network||University of Puerto Rico, Mayaguez||UHF, microwave, ISDN|
|1998||Tsunami Warning Network||US Geological Survey, Golden, Colorado||UHF|
|1999||New Delhi Telemetry Network||India Meteorological Department, Delhi, India||VSAT|
|2000||Seismographic Aftershock Monitoring System (SAMS)||Test Ban Monitoring||Spread Spectrum radio|
|2000||Small Aperture Infrasound array||Federal Institute for Geosciences and Natural Resources, BGR (Bundesanstalt fuer Geowissenschaften und Rohstoffe), Hannover, Germany||GSM|
|2002||Seismograph Telemetry Network around Edinburgh||British Geological Survey||UHF|
|2004||Seismic Telemetry Network||Institute of Physics of the Earth (IPE), Masaryk University, Brno, Czech Republic||Spread Spectrum Radio|
|2005||National Operative Telemetry System for Seismological Information (NOTSSI)||Geophysical Institute Bulgarian Academy of Sciences, Sofia, Bulgaria||ISDN, VPN, MAN|
|2006||DAM monitoring system||EDELCA,Venezuela||Spread Spectrum Radio|
|2006||German Indonesian Tsunami Early Warning System||GeoForschungsZentrum Potsdam (GFZ)||Global VSAT communication|
|2007||Dam Monitoring Telemetry network||Theri Hydro Dam Corporation, India||Spread Spectrum Radio|
|2008||Zaragoza Bridge Monitoring system||Direccion General de Obras Publicas del D.F. & Terracon, Mexico City, Mexico||Spread Spectrum Radio|
|2009||Jordan National Seismic Telemetry network||Jordan Seismological Observatory (JSO), Amman, Jordan||VSAT|
|2010||Telemetry network in North-East of India (in progress)||India Meteorological Department (IMD), New Delhi, India||VSAT|
|2012||Aswan Dam Strong-Motion Array (in progress)||National Research Institute of Astronomy and Geophysics (NRIAG)||GSM|