Monday, April 6, 2009

Introduction of 3g for mobile communication system



The third generation (3G) of mobile communication system is currently under implementation and rollout in Norway. The development and diffusion of 3Gh in Europe is in general facing major delays and difficulties, drawing a picture in sharp contrast with the great expectations formerly associated with the technology. The difficulties and delays occur for many reasons, and some important ones will be spelled out here by describing the basic features of 3G, the innovation and rollout process and the different stakeholders. Using the concepts of innovations and the conceptual framework of innovation regimes described by Godø (Godø 1995), the current state of 3G in Norway is described, followed by explanation concerning the state of the game as well as some brief suggestions for the further development.
The implementation of 3G networks in Norway and the other European countries follows the European Telecommunications Standards Institute (ETSI) standard Universal Mobile Telephone system (UMTS). The aim of the UMTS standard is to create one European mobile telephone network enabling users to use their mobile handsets to access high-value services seamlessly in Europe, and finally all over the world. Telecommunication systems have a historically high strategic significance in modern and industrial societies (Godø 1995). This also concerns UMTS in future Europe as part of the information society spelled out by The Commission of European Communities:

“Advanced wireless platforms such as 3G are an essential building block to achieve the goals of the Information Society in terms of consumer demand, productivity, competitiveness and job creation.”(EU 2002).

In the scattered populated and topologically complex geography (in terms of mobile infrastructure implementation) of Norway, the governmental telecommunication policy has also historically been seen as fundamental to sustainable regional development, are described as the political aims for UMTS in the hearing of the Norwegian Ministry of Transport and Communications concerning the Norwegian mobile communication market:

“Ensure households and businesses all over the country basic telecommunication services with high quality and low price; Ensure maximum of value creation and efficient utilisation of the resources in the telecom sector by ensuring access and efficient use of the public telecommunication network and services by effective competition.” [Authors translation](NMTC 2002a).



Telecommunication is in addition seen as a source for industrial and job opportunities, by exporting technology and knowledge to other European and non-European countries (NMTC 1999). The achievement of these stated aims is expected to come by enabling effective competition in a liberalised telecommunication market. In the case of Norway it can be argued that policy makers and the telecommunication operators both have to meet the classical challenges for less developed regions of the world described by McDowell: The expansion of the telecommunication infrastructure due to the geographical challenges, and the challenges for the post-industrial North: the issues of competition, pricing, and social objectives (McDowell 2001), to succeed in implementing UMTS.

The strategic importance of telecommunication is also reflected in the numerous national and international governmental bodies concerned with the use of frequencies, attribution of licences and competition. In Norway, the Norwegian Ministry of Transportation and Communication, the Norwegian Post and Telecommunications Authority, the International Telecommunication Union (ITU) and different EU[1] bodies have the major stake in the current regulation policies. The operators and other stakeholders are also given a voice in numerous hearings. National regulations in telecommunication have in Norway lately undergone changes as to suite the relatively newly deregulated and liberalised European telecommunication market. The deregulation has resulted in an open market, where the monopoly situation of the state owned “Televerket” no longer exists de jure. De facto, Telenor (formerly “Televerket”) still has a significant market position in mobile communication, and together with the second largest operator: NetCom, respectively having 62.5% and 26.3% percent of subscriptions and 70.2% and 21.4% of the traffic minutes (Statistics for 2001, NPTA 2002a), the market are basically a duopoly. The strong position of Telenor have been an important issue for national regulation bodies, trying to secure the access to the existing European mobile communication system GSM network and the market for new entrants (as for example Sense, the third largest operator having 5.44% of subscriptions and 4.69% of traffic minutes) to create effective competition and correct pricing of the services. Actors (Telenor and NetCom only) with their own physical network have obviously more flexibility than the operators and service providers without. This is acknowledged by the Ministry of Transportation and Communication through obligating licensees to build parallel and completely independent UMTS networks.
1. Sharing the airRadio frequencies combined with antennas and transmission effect enables communication over different ranges. The different ranges make some frequencies more popular than other, and they eventually become crowded. Radio frequency regulation authorities are responsible for regulating the use of different frequencies so that communication doesn’t break down, as well enabling a maximum of utilization. Regulations are implemented by licensing the use and appropriate the different parts of the frequency spectrum to different purposes, and different licensees. GSM and UMTS
Norway is not a member state of the European Union, but is associated by the European Economic Area (EEA). Norway is therefore required to adapt its telecommunication regulatory framework according to EU directives through that treaty.


are appropriated different bands in the frequency spectrum, fitting the frequency regulation tables of Norway as well as Europe in general. In practice, the licensees them selves are responsible to effectuate sharing policies and avoid disturbance of other licensees and end-users. To ensure this, the very much of the spectrum requires the individual end-users to be certified prior to use. This is not the case of GSM and UMTS, as the responsibility and certification is handed over to the handset manufacturers by certification of products.

Mobile communication system configurations are based on cells. The cell is a circular area surrounding the base-stations that is delimited by the radius of reach of base-stations signals. The end-user communicates with other end-users through the base-stations that are connected with fixed cables. To keep users connected as they move between cells, or roam[1], the infrastructure must basically be configured such that cells are overlapping, illustrated by Figure





Roaming can be defined more specifically to be movement between cells or access to network of other operators nationally or globally. Here, roaming is not restricted to include only one, but both these processes.
Sharing the air is a challenge when more than one user is communicating in the same cell at the same time. If this happens, and users use the same frequencies, transmissions will brake down. These collisions can be avoided by not reusing frequencies in a cell and in adjacent cells, as frequencies used in cell c1 can be reused in cell c8, but not in the other cells (Figure 1). Mobile communication systems implements in addition more advanced procedures to share the air. GSM uses frequency sharing based on time-slots, implying that users only use a frequency for 0.5 milliseconds before others can use the frequency. Using this schema, the users must be granted new frequency and new time slot each time they switch to a new base-station when roaming, making the handover procedure complicated. The smaller cell, the more often handover must be effectuated. The high density of use in urban areas, and also in more rural due to the high penetration of mobile phones in Norway, requires in addition more sophisticated use of frequency sharing, implemented by UMTS. Instead of sharing the air by division of frequencies and time UMTS spreads radio signals over a range of frequencies, using CDMA (Code Division Multiple Access). With this schema other concurrent transmission is just seen as noise.
These schemas are called respectively frequency division multiple access (FDMA) and time division multiple access (TDMA).
This makes the theoretical simultaneous users much higher than with GSM, as well as making the handover procedures easier as the same schema and frequencies are used by any base-stations. At the same time, the bandwidth is highly dependent on the number of users in one and the same cell, as well as which kind of data is communicated. If all users in a UMTS cell are using the lowest transmission capacity (voice), 256 concurrent users can communicate simultaneously. If everyone uses maximum capacity (multimedia), only two concurrent users are possible.

The frequencies used by GSM have a range of maximum 35 kilometers while the UMTS frequencies only reach 6 kilometers, both due to the nature of the frequency band and the bandwidth provided. The range of transmission decides how large cell the base-station creates, and the needed density of base-stations. Using different effect in transmission, different cell sizes are implemented in UMTS networks to optimize the available bandwidth on the basis of user density (e.g. macro-, micro- and pico-cells). The bandwidth available will also be affected when the handsets are one the move, and decreases as the speed increases, as high-speed radio access to highly mobile users is difficult. This illustrates the need for a much higher density of UMTS base-stations, at a cost of approximately 1 million NOK each. In addition, the broadband cabled network coupling the UMTS base-stations to the cabled network would probably become as expensive as the base-stations.

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