Wireless E 9-1-1 in theGarden State
by S. Robert Miller
Amid a world of doubters and disbelievers, the FCC took stepsin support of Wireless E9-1-1 and issued 94-102 rule making whichcalled for wireless Automatic Number Identification (ANI) within18 months and wireless Automatic Location Identification (ALI)within 5 years. This was supported by public safety agenciesacross the land. Two states, with the help of several vendorswhich have been strong supporters of the goals of NENA, set outto prove that Phase I (ANI in 18 months) and Phase II (ANI/ALI infive years), directives of 94-102 were not only possible toachieve technically, but could be achieved sooner rather thanlater.
Within six months of the FCC’s order, the States of Texas and NewJersey met the FCC’s order for both Phase I and Phase II. TheLone Star State and the Garden State had slightly different goalsand took different approaches which strengthened the position ofNENA and the “joint commenters” that the goals of94-102 could be accomplished in a multiplicity of ways. Thisarticle is about the wireless trials held in New Jersey.
The first wireless trial in the Garden State was held inOctober 1994. The project was formed and coordinated by the NewJersey Office of Emergency Telecommunications Services (OETS) andBell Atlantic. Members of the project included: Rockwell, SmithAdvanced Technology (SAT), OETS, Bell Atlantic, and theGloucester County Communications Center. The project utilized theGlobal Positioning System (GPS) and SAT equipment. As test callswere initiated, SAT equipment uploaded the GPS information overthe cell link to a SAT processor which plotted the caller andsent routing instructions and other location information to aRockwell SCX 9-1-1 tandem.
The Rockwell SCX tandem routed the call to one of two PSAPpositions established at the Gloucester County CommunicationsCenter in South Jersey. One position covered Gloucester Countyand the other position covered Philadelphia which is due West ofGloucester County and across the Delaware River. The systemplotted the pseudo 9-1-1 test calls and displayed the caller’slocation, speed, and direction on a computer mapping terminal.
The trial used cellular mobile phones mounted in a vehiclecoupled with a GPS receiver, both with roof- top mountedantennas. The system worked extremely well and the trial was acomplete success. However, it appears questionable that thissolution fills the total needs of today’s society. Today, peopleare purchasing portable cellular and PCS phones in large numbersand using them inside buildings, trains and automobiles, etc. -places where GPS transmissions cannot be received.
In the spring of 1996, a second wireless project team was formedin the Garden State. This project is also coordinated by OETS andBell Atlantic.
Time-difference-of-arrival (TDOA) technology was selected forthis project. The project partners are: the Associated Group,Comcast Cellular Communications, OETS, Bell Atlantic, Rockwell,KML, MapInfo, On-Target Mapping, QED, SCC Communications, and theCounties of Burlington, Camden, Gloucester, and Salem. InOctober, the Associated Group placed 24 TruePosition TDOAreceivers at Comcast Cellular sites in the New JerseyTurnpike/I-295 corridor and KML installed their enhanced PSAPterminals.
On January 22, 1997, the system was turned up live for 9-1-1calls in the trial area. The trial area covers 50 miles of theNew Jersey Turnpike and I-295 corridor from the NewJersey/Delaware State border to Bordentown which is just south ofTrenton, the State Capital (see Figure 1). Unlike the previoustrial, the system does not require modifications to existingcellular phones nor does it require a clear view of several GPSsatellites. The receivers are connected via Comcast data links toa TruePositionTM Signal Collection System (SCS) which calculatesthe 9-1-1 caller’s location, nominally, within 125 meters 67percent of the time (see Figure 2). At other times, theresolution will be greater or less than 125 meters. Theinformation is then passed to a SCC Communications SR/ALIcomputer.
The SCC SR/ALI computer determines the Emergency ServiceNumber (ESN) of the wireless caller based on the latitude andlongitude of the caller and dynamically creates Selective Routing(SR) and ALI records. The call arrives at the Rockwell SCX 9-1-1tandem on “Feature Group D” (FGD) trunks from thecellular Mobile Switching Office (MSO). The SCX 9-1-1 tandem thenqueries the SCC computer for the ESN and ALI information. The SCCcomputer sends the ESN, latitude/longitude, speed, and directionof the caller to one of New Jersey’s three Rockwell 9-1-1 tandemsover data links.
The Rockwell 9-1-1 tandem routes the call based on the ESNreceived from the SCC computer. The Rockwell tandem then sendsthe ANI, ALI (latitude/longitude), direction, and speed of thecaller to the PSAP. This is accomplished over the standard PSAPcircuits which are used for wireline calls. No additionalcircuits are needed to the PSAP for the wireless calls.
The 9-1-1 calls are answered at the PSAP with KML (AdvancedRockwell IPSAP) terminals with mapping software developed byMapInfo and On-Target Mapping with the assistance of QED. The NewJersey Master Street Address Guide (MSAG) data was createdgraphically, and maps with the Emergency Service Zones (ESZs),are available statewide. The KML terminals display a standardtype ALI screen formatted for wireless data (see Figure 3).
The terminals display the cell site, roam access number,calling party ANI, ALI in latitude/longitude, speed, direction,and the emergency service providers (police, fire, EMS). Theterminals then map the wireless call utilizing the MapInfo andOn-Target software. The same PSAP terminals can be used forwireline calls and can display maps of those calls based onstreet addresses. This project is the first wireless project inthe nation to pass live Phase II 9-1-1 calls to local PSAPs.
As the demonstration project is in its final stages, New Jerseyis looking ahead for full statewide implementation of both PhaseI and Phase II. It is anticipated that Phase I will beimplemented statewide by the end of 1997. Statewideimplementation of Phase II hinges on the establishment of afunding mechanism and the development of digital air-interfacelocation receivers.
The New Jersey and Texas trials have demonstrated conclusivelythat wireless ANI and ALI is possible and achievable within thetime frames established by the FCC. It is now up to the”covered carriers” to work with the location vendors oftheir choice to develop systems which will work with theair-interface standard that they have chosen. This need not be acomplicated issue. Compliance with 94-102 is a question of will -not a question of can do.
The current New Jersey demonstration is open to the publicsafety community, equipment vendors, wireless providers, and anyother interested party. The demonstration will continue throughthe end of March. Anyone interested in viewing the demonstrationcan contact New Jersey OETS, Bell Atlantic, or any of thepartners in the project. A full report of the project is beingplanned for the 1997 Annual NENA Conference in Baltimore. Hope tosee you then!
S. Robert Miller is Executive Director of the New JerseyOffice of Emergency Telecommunications (OETS), Chair of the NENATechnical Advisory Board, and a member of the NENA PSAP StandardsAdvisory Board.