Take a Position

Many people associate location technology with the U.S. FCC mandate to locate 911 callers. However, two other potential uses exist as well: law enforcement and commercial applications. Now is a critical time for location technology. The price and performance must meet critical benchmarks, and the industry still must determine who is going to pay for what.

The FCC 911 mandate has two location components, first to provide information about the cell or sector from which a 911 call was made (by 1998) and then to provide 125-meter/400-foot accuracy (by 2001). As technology advances, the FCC may tighten the accuracy requirements and may include height as well as latitude and longitude. But the FCC mandate has a loophole. The PSAPs have to indicate a readiness to receive location data. If they feel that the technology will be too expensive for them or not reliable enough, they may not ask for wireless carriers to support the mandate.

PHONES VS. NETWORKSApart from cost and accuracy, another critical issue is whether existing wireless phones will need to be upgraded. GPS, for example, provides high accuracy in relatively open areas (where the phone has a clear view of multiple satellites) but would require a phone upgrade or, more likely, an entirely new phone. The FCC has been coy on whether a terminal-based solution will be acceptable.

A network-based solution requires radio receivers to be placed strategically around the coverage area (possibly, but not necessarily, co-located with cell sites). The accuracy of the position fix varies with the distance and orientation of the nearest measuring stations. The problem with the network approach is the cost of the many necessary receiving stations, without which you could not obtain sufficient accuracy. The advantage is that it will work with existing phones.

However, each technology requires a different approach. Analog phones are the easiest to locate because an entire 30kHz (10kHz for N-AMPS) is dedicated to a single mobile. TDMA maintains the 30kHz bandwidth but requires the monitoring equipment measure only during the monitored mobile's assigned time slots. Plus, TDMA supports temporary mobile station identifiers that obscure the true identity of the mobile (making communication with the MSC mandatory). CDMA, the most complex wireless technology and the one technology explicitly designed to avoid eavesdropping, is the hardest technology to track. Many CDMA phones and cell sites share the same 1.25MHz frequency band; all transmit simultaneously, and they change power levels rapidly.

The solution choice will make a big difference to law enforcement, which appears likely to get access to the same location-tracking capability as 911 (although only with certain types of court orders), at least according to proposals in the latest FCC Notice of Proposed Rulemaking on CALEA. A handset-based solution would give wireless phone users the ability to know when they were being tracked, which would make this solution much less useful for law enforcement. A network-based solution should be completely transparent and, thus, much more useful for the boys in blue.

LOCATION APPLICATIONSThe greatest variety of applications lies within the commercial realm, although most are in field trials and have not yet been proven. One of the most talked about is location-sensitive billing, which could allow subscribers to have lower airtime rates in the vicinity of their homes or offices or in campus environments. Currently, these applications can be based solely on the serving cell or sector, the size of which varies greatly from areas with a high call volume (with cells covering tiny areas, and with many sectorized cells) to areas with a low call volume (with cells covering huge areas). If E-911 technologies can routinely deliver 125-meter accuracy, then a subscriber can be located at least within a block of his home.

There are several other consumer-oriented services under discussion. Enhanced 411 will enable phone numbers to be provided for businesses in the desired category closest to the caller's location. There may be specialized versions of this, where the dialed digits imply the business category. (*AAA could call a roadside emergency dispatcher and direct the tow truck to the location of the breakdown.) A navigation service, knowing where the caller is, could provide directions to a specific address.

More mundane (but possibly more lucrative) location services will be aimed at businesses. Wireless phone transceivers could be used for wide-area tracking of vehicles or freight containers. You even could track people in this way. For example, you could track users of stolen wireless phones. This would help recover the phone as well as the cost of the calls.

There is no question that the range of location technology applications is wide, but the technology's success still is not assured. The biggest questions revolve around cost and capability. Every segment of the market with an interest in location technology can think of a good reason for another segment to pay for the infrastructure.

The 911 community is not eager to pay to bring wireless phones close to the same level of functionality that wireline phones currently provide at a fraction of the cost. The law enforcement community hopes to piggyback on an existing infrastructure. And carriers certainly hope that commercial services will prove to be a big money spinner, but whether they actually will still is unknown. Although it is certain that youthful location technologies will continue to increase in performance as they lessen in price, it is not certain that the wrangling over funding will be resolved any time soon.

Although E-911 is a federal mandate, the success of its implementation hinges largely on how it's handled at state and local levels. Case in point: cost recovery. Each state has to create a mechanism that funds public-safety upgrades for E-911 before it can require wireless carriers operating there to provide E-911 information to public-safety agencies. By December 1998, 21 states had created cost-recovery mechanisms.

One convenient way to track state E-911 legislative activity is http://www.xypoint.com/html/public-policy, a web site operated by E-911 vendor Xypoint.

Cost recovery is key because many public-safety agencies, particularly in rural areas, lack the equipment and expertise necessary to process the detailed information that E-911 can provide. At a November conference on E-911, one public-safety official noted that some agencies still use pen and paper to take down caller information and then pinpoint it on a paper map. Connecticut and Vermont are the first two states to deploy statewide public-safety networks designed to handle E-911.