As children playing hide and seek, there seemed to be so many places where we could hide and never be found. With the world becoming ever smaller through technology, hiding is increasingly difficult. Cameras peer down on us at red lights, in our workplace, in stores and even at home. Now, those cameras are being augmented by new technologies that track our cars, cell phones and possibly any product we buy.
This location-tracking technology also is being used to streamline supply chains for corporations, seeking to move products to the market faster, and to monitor assets and prevent inventory loss.
Soon, companies also will be able to track your location. Imagine walking through your local supermarkets, and as you pass through the aisle, an electronic coupon for your favorite cereal is beamed to your phone.
However, many privacy advocates are worried about the implications of these new surveillance systems. Such technology means that marketers and others could know your whereabouts at any time.

Tracking Technology

Location tracking is not one, single technology. Rather, it is the convergence of several technologies that can be merged to create systems that track inventory, livestock or vehicle fleets. Similar systems can be created to deliver location-based services to wireless devices.
Current technologies being used to create location-tracking and location-based systems include:

Geographic Information Systems (GIS) - For large-scale location-tracking systems, it is necessary to capture and store geographic information. Geographic information systems can capture, store, analyze and report geographic information.
Global Positioning System (GPS) - A constellation of 27 Earth-orbiting satellites (24 in operation and three extras in case one fails). A GPS receiver, like the one in your mobile phone, can locate four or more of these satellites, figure out the distance to each, and deduce your location through trilateration. For trilateration to work, it must have a clear line of sight to these four or more satellites. GPS is ideal for outdoor positioning, such as surveying, farming, transportation or military use (for which it was originally designed). See How GPS Receivers Work for more information. Photo courtesy U.S. Department of Defense Artist's concept of the GPS satellite constellation
Radio Frequency Identification (RFID) - Small, battery-less microchips that can be attached to consumer goods, cattle, vehicles and other objects to track their movements. RFID tags are passive and only transmit data if prompted by a reader. The reader transmits radio waves that activate the RFID tag. The tag then transmits information via a pre-determined radio frequency. This information is captured and transmitted to a central database. Among possible uses for RFID tags are a replacement for traditional UPC bar codes. See How RFIDs Work for more information.
Wireless Local Area Network (WLAN) - Network of devices that connect via radio frequency, such as 802.11b. These devices pass data over radio waves and provide users with a network with a range of 70 to 300 feet (21.3 to 91.4 meters).

Any location tracking or location-based service system will use one or a combination of these technologies. The system requires that a node or tag be placed on the object, animal or person being tracked. For example, the GPS receiver in a cell phone or an RFID tag on a DVD can be used to track those devices with a detection system such as GPS satellites or RFID receivers.

Types of Tracking

Companies are finding location-tracking technologies ideal for better managing inventories or fleets of vehicles. Knowing the exact location of each piece of inventory helps to control the supply chain and saves money by not losing those assets that are in transit. Companies, such as retailers, must consider how to track inventory across a wide area, either country or state, and in a smaller area, such as the warehouse or store.

Wide-Area Tracking

On a large scale, companies must track their vehicle fleets across the country or the world. GPS is the ideal tracking technology for tracking over large areas. To do this, every vehicle needs to be equipped with a GPS receiver. As the vehicle crosses the country, the GPS satellites track the truck's position. With GPS, the operator can request positioning at anytime. However, GPS is limited in smaller areas or indoors.

In America, we learn from an early age to call 911 when there's an emergency. When we dial 911, the call is automatically forwarded to a public-safety answering point (PSAP), also called a 911 call center. When the call is answered, the 911 operator is provided with automatic location information (ALI), pinpointing the exact position of the call. Today, many areas also have Enhanced 911 (E-911), which allows a PSAP to determine the general location from where the call originated, but cannot yet pinpoint the location.

On February 16, 1968, Alabama Senator Rankin Fite made the first 911 call in the United States in Haleyville, Alabama. The Alabama Telephone Company carried the call.

Why 911?

Have you ever wondered why 911 was chosen as the universal emergency code in the United States? Prior to the 1960s, there was no universal number to call for emergency help. In 1967, the Federal Communications Commission met with AT&T to establish such a number, according to the National Emergency Number Association (NENA). But why did they choose 911? Why not 422 or 111?