i-mode tutorial
- a summary, overview or tutorial about i-mode used for cell phone emails
and surfing
i-mode (imode) is cellular technology that has had an
astounding success in Japan. Now the company that launched the system in
February 1999, NTT DoCoMo, is launching other i-mode cell phone systems in other
countries around the world.
i-mode is cellular technology providing an information
service, and this give rise to its name. It is provided as a premium add-on
service to the basic cellular phone system and provides many facilities
including e-mail, internet surfing, and picture mailing. Requiring special
i-mode terminals to be purchased by the user, this cellular technology operates
as a packet based network overlaid on the basic cellular system.
i-mail
One of the most popular aspects of the i-mode service is
i-mail that enables users to send e-mail messages to others on the same service,
or to anyone with an e-mail account.
There are limits to the number of characters that can be sent
and received using this cellular technology, but these are much greater than the
limits that apply to the SMS service that has become so popular on GSM. For
i-mode users can send messages up to 500 characters in length and can receive up
to 4000 characters.
On opening an i-mode account, users are given an e-mail
address that consists of a random mix of characters. This can be changed once
the account has been set up to personalise it for the user, and to make it more
memorable.
Internet access using i-mode
The other major element of i-mode is its ability to surf the
internet and access internet sites. Specially developed websites using a cut
down version of HTML known as cHTML is used to enable sites to be downloaded
more quickly whilst providing content that can be satisfactorily viewed on the
phones. The i-mode menu on the phone enables the user to select one of four
zones: namely Lifestyle (for sports, weather local events etc); Transaction (for
facilities including banking, shopping, credit card information and the like);
Database (for services including traffic updates, TV and radio schedules as well
as cinema information); and Entertainment (where games and music downloads are
available along with screen savers, ring tones and hobby information).
One of the major incentives to the development of the special
i-mode sites is that the operators have been investing in the content developers
to develop official i-mode sites. Rather than splitting the revenues 50/50 as in
the case of other similar systems, a revenue share of 90/10 in favour of the
content developer has been adopted. This has stimulated a healthy growth and
there are many thousands of official i-mode sites, with countless thousands more
unofficial ones that are i-mode compatible. This means that the user has a great
degree of choice and the usage has risen. In this way the operator has been able
to see considerably increased revenues.
On top of these services there is i-shot for taking and
sending pictures as well as i-appli for running applications such as downloaded
games, and i-area for location based services.
The i-mode system
The i-mode system was originally run on the PDC system that
is found in Japan, however it can also be applied to other cellular systems as
well.
Based on a packet transmission to the mobile phones, i-mode
uses a protocol known as PDC-P (Personal Digital Cellular Packet) for the
interchange of data packets. The service is based on a 3 channel TDMA model to
provide a common access system that can be shared by multiple users on a random
access basis. Using multi-slot transmissions across the three channels data
speeds of up to 28.8 kbps can be achieved.
CDMA2000 1X is widespread in Japan, and i-mode system is also
used with this system. As data speeds are very much higher for 1X, this enables
faster and easier access of the data. Services are also available on the faster
data only CDMA2000 1xEV-DO system that enables data transfer at rates up to 2.4
Mbps.
Future
While i-mode is not a mainstream cellular technology in the
same way as GSM, or UMTS for example, it managed to gain a good foothold in a
number of areas. While it may have been originally seen as a rising sun in the
East, it appeared in many other countries to compete with other technologies and
cellular systems.
|
