Sandia National Laboratories has tested and evaluated the performance of the following five models of low-cost infrasound sensors and sensor packages: Camas microphone, Gem Infrasound Logger, InfraBSU sensor, Raspberry Boom, and the Samsung S10 smartphone utilizing the Redvox app. The purpose of this infrasound sensor evaluation is to measure the performance characteristics in such areas as power consumption, sensitivity, self-noise, dynamic range, response, passband, linearity, sensitivity variation due to changes in static pressure and temperature, and sensitivity to vertical acceleration. The infrasound monitoring community has leveraged such sensors and integrated packages in novel ways; better understanding the performance of these units serves the geophysical monitoring community.
Sandia National Laboratories has tested and evaluated various infrasound shrouds , produced Do ug Seastrand and Gary Walker, DOE staff in Las Vegas, Nevad a, intended for a Hyperion 5201W digital infrasound sensor . The purpose of these shrouds is to improve the infrasound sensor's attenuation of incoherent signals, specifically those caused by wind pas sing by the sensor. The purpose of the shroud evaluation was to measure amplitude and phase of the sensors with a variety of shroud designs attached and determine whether there is any appreciable changes in amplitude and/or phase response over the IMS p assband for infrasound applications, 0.02 Hz to 4.0 Hz. These shrouds utilize a tubule design that directs and mixes airflow from ports radially distributed at approximately 90 degree offsets in an attempt to minimiz e wind - generated signal due to B ernou lli effect caused by airflow passing by ports perpendicular to the wind. ACKNOWLEDGEMENTS This work was funded by the United States Department of Energy Office of Nuclear Verification (NA - 221). We would like to thank Hyperion Inc, for providing sens or nominal response information and the noise model. We also wish to thank the DOE office in Las Vegas, Nevada for loaning us the digitizer - sensor units and shrouds evaluate d herein .
Sandia National Laboratories has tested and evaluated a new digitizer, the Affinity, manufactured by Guralp Systems. This digitizer is used to record sensor output for seismic and infrasound monitoring applications. The purpose of the digitizer evaluation was to measure the performance characteristics in such areas as sensitivity, self-noise, dynamic range, system noise, relative transfer function, analog bandwidth, harmonic distortion, common mode, cross talk, timing tag accuracy and timing drift. The Affinity provides eight, rather the typical six, channels of 24 bit high sample rate digitization. Moreover, it also provides 16 single-ended, 24 bit resolution, low sample rate auxiliary channels. The Affinity digitizer is undergoing these tests prior to installation in the FACT site infrasound test bed. ACKNOWLEDGEMENTS This work was funded by the United States Department of Energy Office of Nuclear Verification (NA-222).
Sandia National Laboratories has tested and evaluated two Nanometrics Centaur digitizers. The Centaur digitizers are intended to record sensor output for seismic and infrasound monitoring applications. The purpose of this digitizer evaluation is to measure the performance characteristics in such areas as power consumption, input impedance, sensitivity, full scale, self- noise, dynamic range, system noise, response, passband, and timing. The Centaur digitizers are being evaluated for potential use in the International Monitoring System (IMS) of the Comprehensive Nuclear Test-Ban-Treaty Organization (CTBTO).
Sandia National Laboratories has tested and evaluated a digitizer, the SMART24B, manufactured by Geotech Instruments, LLC. These digitizers are used to record sensor output for seismic and infrasound monitoring applications. The purpose of the digitizer evaluation was to measure the performance characteristics in such areas as power consumption, input impedance, sensitivity, full scale, self-noise, dynamic range, system noise, response, passband, and timing. The SMART24B is Geotech's datalogger intended for borehole deployment in their digitizer product line. The SMART24B is available with either 3 or 6 channels at 24 bit resolution. The digitizer is to be deployed in boreholes, therefore are a minimum number of connections required on the digitizer case as datalogger utilizes a distribution panel, mounted up-hole, serving to breakout power, GPS, serial communications and ethernet connections.
Sandia National Laboratories has tested and evaluated a new digitizer, the Affinity, manufactured by Guralp Systems Ltd. These digitizers are used to record sensor output for seismic and infrasound monitoring applications. The purpose of the digitizer evaluation was to measure the performance characteristics in such areas as power consumption, input impedance, sensitivity, full scale, self-noise, dynamic range, system noise, response, passband, and timing. The Affinity digitizer is Guralp's latest release in their digitizer product line. The Affinity is available with either 4 or 8 channels at 24 bit resolution. In addition to the 24 bit channels, 16 multiplexed low resolution channels are provided. Other features include the means to accept multiple types of timing sources (e.g. GPS, NTP and PTP) and a web page interface for command and control of the unit.
Sandia National Laboratories has tested and evaluated a new digitizer, the Q330HR , manufactured by Quanterra . These digitizers are used to record sensor output for seismic and infrasound monitoring applications. The purpose of the digitizer evaluation wa s to measure the performance characteristics in such areas as power consumption, input impedance, sensitivity, full scale, self - noise, dynamic range, system noise, r esponse, passband, and timing. The Q330HR is Quanterra ' s improved Q330 datalogger with a 2 6 bit s of resolution on channels 1 - 3 and a 24 bits of resolution on channels 4 - 6 (26 bit is optional ). The Quanterra Q330HR is being evaluated for potential use U.S. Air Force seismic monitoring systems as part of their Next Generation Qualification effort .
Sandia National Laboratories has tested and evaluated a new digitizer, the Centaur , manufactured by Nanometrics . These digitizers are used to record sensor output for seismic and infrasound monitoring applications. The purpose of the digitizer evaluation was to measure the performance characteristics in such areas as power consumption, input impedance, sensitivity, full scale, self - noise, dynamic range, system noise, r esponse, passband, and timing. The Centaur digitizer is Nano metrics ' replacement for their Taurus digitizer and marks Nanometrics first 6 channel, 24 bit resolution system. Other improvements include LED status indicators on the top of the unit, providing basic status of the core systems of a seismic station (e.g. timing, sensor SOH, storage, etc), an optional wifi system allowing password protected access to the unit and a web interface for monitoring and configuration of the unit. The Nanometrics Centaur is being evaluated for potential use U.S. Air Force seismic monitoring systems as part of their Next Generation Qualification effort .
The Seismo - Hydroacoustic Data Acquisition System (SHDAS) is undergoing evaluation in preparation for its engineering, development, and deployment by the U.S Navy as an ocean bottom seismic monitoring system. At the current stage of development, the production seismometers are being evaluated to confirm their performance prior to packaging and assembly for deployment. The testing of the seismometers is being conducted at the Pinon Flats Observatory (PFO) , supervised by Sandia National Laboratories, U.S Navy, and RP Kromer Consulting. SNL will conduct evaluation of the collected seismometer data and comment on the performance of the seismometers.
Sandia National Laboratories has tested and evaluated three seismometers, the Trillium 120PH, manufactured by Nanometrics. These seismometers measure broadband ground velocity using a UVW configuration with feedback control in a mechanically levelled borehole package. The purpose of the seismometer evaluation was to determine a measured sensitivity, response, self- noise, dynamic range, and self-calibration ability. The Nanometrics Trillium 120PH seismometers are being evaluated for the U.S. Air Force as part of their Next Generation Qualification effort.
Sandia National Laboratories has tested and evaluated two seismometers, the STS-5A, manufactured by Kinemetrics. These seismometers measure three axes of broadband ground velocity using a UVW configuration with feedback control in a mechanically levelled borehole package. The purpose of the seismometer evaluation was to determine a measured sensitivity, response, self-noise, dynamic range, and self-calibration ability. The Kinemetrics STS-5A seismometers are being evaluated for the U.S. Air Force as part of their Next Generation Qualification effort.