Platform-Based Testing of Station-Based GNSS-Positioning, Accelerometer and Ensemble Streams for Early Warning Applications With the ‘HERB-SE’

Date: 4/25/2019

Time: 06:00 PM

Room: Grand Ballroom

High-rate, low-latency Global Navigation Satellite System (GNSS) data are being utilized for real-time (RT) applications focused on disaster mitigation, including tsunami early warning. By directly reporting displacement waveforms (particularly for lower frequencies and ‘DC’ coseismic offsets), RT-GNSS complements other geophysical monitoring (i.e., accelerometer) networks to improve the robust assessment and reporting of hazards. In order to facilitate real-time testing of distributed (on-site) analyses as well as integration with other local seismic sensors, Natural Resources Canada’s Canadian Geodetic Survey has implemented real-time GNSS processing on low power, Linux platforms. Currently three RT-time positioning streams may be executed in-situ: precise point positioning (PPP) with integer ambiguity resolution and ‘float’ PPP (both using RT clock and orbit correction streams delivered to the GNSS sites) as well as fully autonomous single point positioning using broadcast orbits.

To evaluate the RT-GNSS derived coordinate streams in a controlled experiment, a mechanical system is used to drive a GNSS antenna along a circular path while maintaining a fixed orientation. The result is the ‘HERB-SE’ – Highly Economical Rotating Base (Second Edition) – employed to test real-time single station-based position, accelerometer & combined output streams. Through the use of this platform, the reliability (amplitude and period accuracy) and noise characteristics of the currently available (and, possibly, developmental) RT-GNSS streams are evaluated. Furthermore, a strong-motion accelerometer (SMA) may be located beneath (and co-axial to) the GNSS antenna and operated simultaneously. RT-GNSS position streams and RT-SMA observations may be combined in real-time; and both streams are independently recorded producing data sets employed to further optimise algorithms and parameters used to process and/or fuse GNSS and SMA data streams. This presentation will review the testing platform, RT-GNSS processing results and the ensemble seismo-geodetic observations.

Presenting Author: Joseph A. Henton

Authors