The history of 4G
4G I-MODE TECHNOLOGY, JAPAN
In March 2002 NTT DoCoMo announced that trials
had begun on the next generation of mobile communications.
Dubbed '4G', the new I-mode technology will increase data
transmission rates (up to 200 times faster than 2G at 20Mbit/sec).
3G data rates are currently 2Mbit/sec, which is very fast
compared to 2G's 9.6Kbit/sec. 4G builds on the 3G standard,
although it integrates and unifies the different interfaces
(W-CDMA, CDMA2000, EDGE, etc).
4G I-MODE TECHNOLOGY
Since December 2000, NTT DoCoMo and Hewlett-Packard
have been jointly developing the software and hardware that
make high-speed wireless possible. In October 2001, 3G was
successfully rolled-out in Japan, and the new technology will
depend on using the established base stations and mobile station
equipment. The introduction of 3G technology provided a huge
expansion in mobile capacity and bandwidth, and 4G will do
the same for the spectrum of broadband communications.
about the new technology has been rife, as the success of
3G has been questioned in both Europe and the USA. One of
the main concerns about 4G is that the speed of the frequency
suggests that it will experience severe interference from
multi-path secondary signals reflecting off other objects.
There have been a number of proposed solutions, including
using a variable spreading factor (VSF) and orthogonal frequency
code division multiplexing (OFCDM).
concerns involve cost and the compatibility of various applications,
although these are expected to be ironed out in the coming
months. For example, FOMA-enabled videophones cannot be used
for I-motion music and video links; and the N2002 handset
erases parts of the phone's memory if certain websites are
accessed. Finally, the cost of I-mode mobile phones is too
high for most users, therefore the technology will probably
be consigned to corporate use for the foreseeable future.
is suggested that 4G technologies will give way to 3-D virtual
reality and interactive video/ hologram images. 4G will increase
interactions between corroborating technologies, so that the
smart card in your telephone will automatically pay for goods
as you pass a linked payment kiosk - or will tell your car
to warm up in the morning, because your phone has noted you
leaving the house or setting the alarm.
is expected to provide better-than-TV quality images and video-links,
although it is likely that forecasts will change as customer
demand develops over time. The communications model has developed
new versions of HTML, Java, GIF, HTTP and many more. It is
expected that new standards will need to be developed for
the use in 4G.
JAVA-BASED I-MODE PROGRAMS
of Java-based I-mode programs, include the i ƒ¿ppli,
which downloads maps and displays charts of online information.
It also enables remote users to receive automatic notifications
of weather, traffic, appointments, etc. both online and from
a company intranet. The main bonus for users of the software
is the additional security encryption, which makes it suitable
for e-commerce and mobile banking. This system was developed
in conjunction with Sun Microsystems.
is expected that DoCoMo will roll out the 4G technology platform
across Japan in 2006. Other major telecoms operators, such
as Ericsson, Lucent and Nokia are researching 4G technology,
and in Summer 2002 are expected to begin practical evaluations.
These will test data transfer speeds of up to 260 times faster
than the current 3G network.