This project describes a system that provides the indoor location of a 9-1-1 caller who using a smartphone while inside a building. The system consists of a platform that provides the location information and a smart phone application that obtains location information and uses it to make a Next Generation 9-1-1 call. The platform utilizes an array of Bluetooth Low Energy (BLE) devices (iBeacons), a database containing the identification and location of each iBeacon, and a server that processes information from the smart phone by extracting information from the database, calculating the location of the caller, and returning this location information to the phone application. We will describe the platform and the application. Information about the architecture of the service platform and their product operations and maintenance are also included. Test accuracy of the caller’s location is included, along with those results. Finally, proposals for potential other uses for the platform will be revealed.
Overview and Background – Indoor Location Service
When a person calls an emergency number, such as 9-1-1, in the U.S., the callers location must be provided to the network. This achieves two purposes: first, to route the call to the appropriate answering point; and, second, to display the caller’s location to the operator, who will dispatch emergency first-responders to the location. When the call is made from a mobile device inside a building, the operator and first responders need more information than the latitude and longitude and/or the street address to find the caller. They need precise indoor location information, such as a floor and room number. This project describes a proof of concept system, which provides the floor and room number, as well as the street address of a caller. The system was developed in response to the ‘Roadmap for Improving E911 Location Accuracy developed by an alliance of the Association of Public- Safety Communications Officials-International (APCO), the National Emergency Numbers Association (NENA), and four national wireless carriers, AT&T, Sprint, T-Mobile and Verizon. The system described in this project is integrated with a replica of an Emergency Services IP Backbone Network (ESInet) on a test-bed in the IIT Real-Time Communications Lab. The ESInet is specified by NENA for the carriage of Next Generation 9-1-1 (NG9-1-1) calls [NENA i3 standard].
The system consists of the following four components: (1) A smartphone application that detects the emergency call, obtains the caller’s location, and forwards the call, including location information, to the answering point [FN 2015 paper]; (2) An array of Bluetooth Low Energy (BLE) devices that are deployed on the interior walls of a building at selected locations; (3) A database containing the location of the BLE devices; (4) A location server capable of querying the database to discover the location(s) of particular BLE devices, which utilize location information to configure the caller’s location, then format this location, and send the formatted information to the smartphone. .
Figure 1 illustrates these components
To demonstrate this system’s ability to integrate with an Emergency Services IP Backbone Network (ESInet), as specified by the National Emergency Numbers Association (NENA) for the carriage of Next Generation 9-1-1 (NG9-1-1) calls, the calls generated by the proof of concept system are routed to a test-bed in the IIT Real-Time Communications Lab (RTC Lab) that replicates the functions of an ESINet.
The mobile application is built on an Android Operating System, including the functions of a SIP User Agent (SIP UA) provided by the opensource SIPdroid distribution. The iBeacons in the Bluetooth array operate in ‘advertise’ mode only, broadcasting their Major and Minor identifiers every half second. The database is built using MySQL and the location server is a Linux system that includes a node.js module.
For further information on this project, including further descriptions of the service, array, location server, android application, algorithms, experiments and tests, discussion of related work, associated operations and maintenance systems, conclusions and next steps, please visit http://appliedtech.iit.edu/rtc-lab or contact Director, Real-Time Communications Lab of Illinois Institute of Technology/Adjunct Industry Professor of Information Technology and Management, Carol Davids at firstname.lastname@example.org.