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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.
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