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Responder News: Emergency Alert Messaging

Release Date: July 21, 2015

Your handheld device can give you directions based on your current location. In the future, it could also notify you if you are too close to danger! New research being conducted by the Johns Hopkins University Applied Physics Laboratory on how the Wireless Emergency Alerts (WEA) service sends geographically targeted alerts to citizens’ mobile phones focuses on how emergency messages could find their way directly to your cell phone (or other handheld device) based on your current location, rather than by the cellular network range. This work is sponsored by the U.S. Department of Homeland Security’s Science and Technology Directorate.

Digital rendering of a cell phone In a recently published final report, a mechanism called Arbitrary-Size Location-Aware Targeting (ASLAT) is described and compared with existing WEA geotargeting capabilities. Potentially, ASLAT could get information to people more directly, and help keep people away from location-specific emergencies, like a natural gas leak or building fire. Emergency messages about hazards that cover a broader area – such as an earthquake – would continue to be delivered through the existing WEA mechanism.

The report also identifies requirements for ASLAT and changes that would be required in the existing WEA standards to allow location-aware mobile technology to improve geotargeting accuracy.

Last Updated: 01/12/2023
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