Forecasting GNSS Availability
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עברית (Hebrew)
Situational awareness is critical for autonomous vehicles, whether on the ground or in the air. As GNSS (Global Navigation Satellite System) performance can be unpredictable in urban and suburban areas from signals being obscured or blocked by buildings, autonomous systems can not rely on GNSS for accurate positioning.
A new cloud-based solution lets operators know in advance where and when GPS or GNSS positioning is reliable for unmanned and autonomous journeys. It uses high-definition maps and precision orbital modelling to provide a clear picture of the operating environment.
Spirent GNSS Foresight, developed by Spirent Communications, accurately predicts where and when unmanned vehicles, air taxis and drones can operate safely and dependably beyond visual line of sight (BVLOS).
The system can produce forecasts using data from any of the world’s satellite constellations. Risk Analysis aggregates GNSS forecasts to provide best case, worst case, and 90th percentile predictions in a specified area. Delivered as data, a heatmap, analysis, and report, this can be used as part of a CONOPS.
The forecast service enables flight in challenging environments by calculating GNSS availability for every meter, every second, from 1-100 meters altitude, for up to three days into the future.
The technology “overcomes navigation and positioning challenges by providing real-world situational awareness ahead of time for pre-flight, or for real-time performance improvement, through a cloud-based service. It can be used to determine areas that are always safe to fly or operate in, in addition to finding the exact time in a degraded area when specific operational requirements can be met,” according to the company.
The system’s ability to accurately predict where and when autonomous systems will perform enables users to expand operational areas, reduce the number of system disengagements, and provide a greater level of safety and reliability assurance while reducing — or ultimately removing — human involvement in the driving or piloting task, according to gpsworld.com.
