Location-Reporting Technology

Mobile phone companies are under orders from the FCC to incorporate location-reporting technology into cellular phones. Dubbed E-911, or enhanced 911, the initiative is meant to provide law enforcement and emergency services personnel with a way to find people calling 911 from mobile phones when callers do not know where they are or are unable to say. Since no carrier was able to make an October 2001 deadline to fully implement E-911, the FCC issued waivers permitting carriers to add location-detection services to new phones over time so that 95 percent of all mobile phones will be compliant with E-911 rules by 2005. One way manufacturers can address this requirement is by providing cell phones with a Global Positioning System (GPS) capability in which cell phone towers help GPS satellites fix a cell phone caller’s position. Special software installed in the base station hardware serves location information to cell phones, which is picked up at the public safety answering point (PSAP). However, subscribers would need to purchase a new GPS-equipped handset, since this method would not allow legacy handsets to use the location-determination system. Another location-determination technique is called “Time Difference of Arrival” (TDOA), which works by measuring the exact time of arrival of a handset radio signal at three or more separate cell sites. Because radio waves travel at a fixed known rate (the speed of light), by calculating the difference in arrival time at pairs of cell sites, it is possible to calculate hyperbolas on which the transmitting device is located. The TDOAtechnique makes use of existing receive antennas at the cell sites. This location technique works with any handset, including legacy units, and only requires modifications to the network.

Internet-Enabled Mobile Phones

Internet-enabled mobile phones potentially represent an important communications milestone, providing users with access to Web content and applications, including the ability to participate in electronic commerce transactions. The Wireless Application Protocol (WAP), an internationally accepted specification, allows wireless devices to retrieve content from the Internet, such as general news, weather, airline schedules, traffic reports, restaurant guides, sports scores, and stock prices.

Users also can personalize these services by creating a profile that might request updated stock quotes every halfhour or specify tastes in music and food. Auser also could set up predefined locations, such as home, main office, or transit, so that the information is relevant for that time and location. With access to real-time traffic information, for example, users can obtain route guidance on their cell phone screens via the Internet. Up-to-the-minute road conditions are displayed directly on the cell phone screen. Street-bystreet guidance is provided for navigating by car, subway, or simply walking, taking into account traffic congestion to work out the best itinerary. Such services can even locate and guide users to the nearest facilities, such as free parking lots or open gas stations, using either an address entered on the phone keypad or information supplied by an automatic location identification (ALI) service.

One vendor that has been particularly active in developing WAP-compliant Internet-enabled mobile phones is Nokia, the world’s biggest maker of mobile phones. The company’s Model 7110 works only on GSM 900 and GSM 1800 in Europe and Asia but is indicative of the types of new mobile phones that about 70 other manufacturers are targeting at the world’s 200 million cellular subscribers. It displays Internet-based information on the same screen used for voice functions. It also supports Short Messaging Service (SMS) and e-mail and includes a calendar and phonebook as well.

The phone’s memory also can save up to 500 messages— SMS or e-mail—sorted in various folders such as the inbox, outbox, or user-defined folders. The phonebook has enough memory for up to 1000 names, with up to five phone and fax numbers and two addresses for each entry. The user can mark each number and name with a different icon to signify home or office phone, fax number, or e-mail address, for example. The phone’s built-in calendar can be viewed by day, week, or month, showing details of the user’s schedule and calendar notes for the day. The week view shows icons for the jobs the user has to do each day. Up to 660 notes in the calendar can be stored in the phone’s memory.

Nokia has developed several innovative features to make it faster and easier to access Internet information using a mobile phone:

Large display The screen has 65 rows of 96 pixels, allowing it to show large and small fonts, bold or regular, as well as full graphics.

Microbrowser Like a browser on the Internet, the microbrowser feature enables the user to find information by entering a few words to launch a search. When a site of interest is found, its address can be saved in a “favorites” folder or input using the keypad.

Navi Roller This built-in mouse looks like a roller that is manipulated up and down with a finger to scroll and select items from an application menu. In each situation, the Navi Roller knows what to do when it is clicked—select, save, or send.

Predictive text input As the user presses various keys to spell words, a built-in dictionary continually compares the word in progress with the words in the database. It selects the most likely word to minimize the need to continue spelling out the word. If there are several word possibilities, the user selects the right one using the Navi Roller. New names and words can be input into the phone’s dictionary.

However, the Nokia phone cannot be used to access just any Web site. It can access only Web sites that have been developed using WAP-compliant tools. The WAP standard includes its own Wireless Markup Language (WML), which is a simple version of the HyperText Markup Language (HTML) that is used widely for developing Web content. The strength of WAP is that it is supported by multiple airlink standards and, in true Internet tradition, allows content publishers and application developers to be unconcerned about the specific delivery mechanism.

Third-Generation Phones

The world is moving toward third-generation (3G) mobile communications systems that are capable of bringing highquality mobile multimedia services to a mass market. The International Telecommunication Union (ITU) has put together a 3G framework known as International Mobile Telecommunications-2000 (IMT-2000). This framework encompasses a small number of frequency bands, available on a globally harmonized basis, that make use of existing national and regional mobile and mobile-satellite frequency allocations.

Along the way toward 3G is a 2.5G service known as General Packet Radio Service (GPRS), which offers true packet data connectivity to cell phone users. GPRS leverages Internet Protocol (IP) technologies, adding convenience and immediacy to mobile data services. GPRS is ideal for wireless data applications with bursty data, especially WAPbased information retrieval and database access.

GPRS enables wireless users to have an “always on” data connection, as well as high data transfer speeds. Although GPRS offers potential data transfer rates of up to 115 kbps, subscribers will only really notice faster service at the initial connection. The faster speed is in the connect time. At present, users connect at a maximum of 19.2 kbps.

GPRS packet-based service should cost users less than circuit-switched services, since communication channels are shared rather than dedicated only to one user at a time. It also should be easier to make applications available to mobile users because the faster data rate means that middleware currently needed to adapt applications to the slower speed of wireless systems will no longer be needed. To take advantage of GPRS, however, mobile users will have to buy new cell phones that specifically support the data service.

Summary

Cellular phones are getting more intelligent, as evidenced by the combination of cellular phone, personal digital assistant (PDA), Web browser, and always-on GPRS connection into one unit. These devices not only support data communications, they also support voice messaging, e-mail, fax, and micropayments over the Internet as well. Third-party software provides the operating system and such applications as calendaring, card file, and to-do lists. With more cellular phones supporting data communications, cellular phones are available that provide connectivity to PC desktops and databases via Bluetooth, infrared, or serial RS-232 connections. Information can even be synchronized between cell phones and desktop computers to ensure that the user is always accessing the most up-to-date information.