Wireless Future - Telenor

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new door towards the upcoming future generation
of wireless services; it even promises to add
a great deal of value to existing services (i.e.
emergency services, location dependent billing,
local information about weather reports, restaurants,
shopping, and many more).
The name Youngster also reveals the additional
focus to a market which looks to be extremely
promising in terms of using such services in the
near future. Not only do young people take to
using new services faster than the older generations,
but also their lifestyle is naturally highly
mobile, very communication oriented, and they
are interested in personalised information. By
creating tools and services that are attractive for
young people to use, we aim to inspire them to
develop the skills necessary to put these new
technologies and services into use, and to help in
the development of new services through rapid
feedback and adapting ideas to their own preferences
and requirements. This should have various
resulting benefits – both for them and for
society in general. 2) In particular the penetration
of mobile phones among young people is remarkably
high. By extending this to other
aspects of Information Society technology
and making these attractive to young people to
access and use, a growing momentum could be
created amongst young people which would
have a significant effect on the Information
Society revolution. This would also create new
opportunities for services geared specifically at
youth.
Various Positioning
Technologies
There is a large number of developments related
to mobile location services of the future generation.
A broadening range of different position
determining systems such as OTD 3) , TOA 4)
and wireless assisted satellite based positioning
(GPS 5) /GLONASS 6) ) among others are adding a
confusing amount of heterogeneity which seems
to be difficult to address. In addition, the first
GPS chips have successfully been integrated into
GSM handsets 7) , but its services are still too
limited.
From a technological point of view, the aforementioned
technologies are grouped into termi-
nal centric and network centric position determining
systems. The difference is where the
position is actually determined in terms of measuring
some physical signal values like time
differences, signal strength and angle of the
received signal. Another important issue – also
facing future possible location based applications
– is the power to decide if the location
information is forwarded to another party or if it
is kept private. This feature is naturally allowed
by its design on handset centric technologies.
Related also to marketing issues is the increase
in costs related to each technology. A brief definition
of each mentioned localisation technology
is provided in the following paragraphs.
Cell ID
Depending on the base station with the best signal
strength budget, the serving base station cell
area coverage is used as a rough estimation of
the caller. Accuracy highly depends on the
actual cell size like macro/micro/pico cells
(average size of macro cell = 30 kilometres,
micro cell = 5 kilometres, pico cell = 0.5 kilometre).
Due to optimisation purposes, cells are
more often sectored into three or less often to
other topographic related values which allows to
narrow down further the coverage area and thus
serve more customers with only one physical
site. Cell ID is sometimes also referred to as Cell
of Origin (COO).
Timing Advance
Within one serving cell, a time is allocated to the
determined time difference of actual arrival of a
signal from the mobile handset. The accuracy
also depends – like Cell ID – on the cell size and
the sectoring factor.
OTD (Observed Time Difference)
The signals from at least three geographically
distributed base stations are received by the
handset and optionally 8) also by a reference station
called LMU (location measurement unit).
The handset and the LMU forward the time differences
of arrivals to a central computer centre,
and the location is then calculated there using
triangulation formulars and applying the co-ordinates
of the known location of the involved base
stations.
2) eEurope: An Information Society For All
3) OTD-Observed Time Difference such as E-OTD (Enhanced Observed Time Difference) and
OTDOA (Observed Time Difference of Arrival)
4) TOA-Time Of Arrival
5) GPS-Global Positioning System
6) GLONASS-GLObal NAvigation Satellite System
7) http://www.benefon.com/
8) In the case of unsynchronised base stations.
Telektronikk 1.2001