Geolocation and assisted GPS

Currently in development, numerous geolocation technologies can pinpoint a person's or object's position on the Earth. Knowledge of the spatial distribution of wireless callers will facilitate the planning, design, and operation of next generation broadband wireless networks. Mobile users will gain the ability to get local traffic information and detailed directions to gas stations, restaurants, hotels, and other services. Police and rescue teams will be able to quickly and precisely locate people who are lost or injured but cannot give their precise location. Companies will use geolocation based applications to track personnel, vehicles, and other assets. The driving force behind the development of this technology is a US Federal Communications Commission (FCC) mandate stating that by 1 October 2001 all wireless carriers must provide the geolocation of an emergency 911 caller to the appropriate public safety answering point. Location technologies requiring new modified, or upgraded mobile stations must determine the caller's longitude and latitude within 50 meters for 67 percent of emergency calls, and within 150 meters for 95 percent of the calls. Otherwise, they must do so within 100 meters and 300 meters, respectively, for the same percentage of calls. Currently deployed wireless technology can locate 911 calls within an area no smaller than 10 to 15 square kilometers. It is argued that assisted-GPS technology offers superior accuracy, availability, and coverage at a reasonable cost     

Establishing wireless communications services via high-altitudeaeronautical platforms: a concept whose time has come?

The focus of this article is high altitude aeronautical platforms (HAAPs) such as airships, planes, helicopters, or some hybrid salutions which could operate at stratospheric altitudes for significant periods of time, be low-cost, and be capable of carrying sizable, multipurpose communications payloads. Of particular interest are ways to implement cellular/PCS or high-speed data networks in airborne platforms. From a communications perspective, HAAPs would have many advantages over both their terrestrial and satellite counterparts. If HAAPs prove to be reasonably stable, reliable, and not too costly, they will offer considerable opportunities for wireless services provision, and the introduction of innovative communications concepts such as cell scanning and stratospheric radio relays