Efficient Usage of UMTS/IMT-20001 Spectrum and Future Developments

A considerable growth in traffic volumes of 2nd Generation mobile services was noted during the last two years, growth of usage for voice services by existing and new customers but also growth of usage of all non-voice services. There is a need to have an access to the appropriate spectrum resources to cope with this traffic, in the adequate time frame and in the harmonised manner in order to answer to the massive use of radiocommunications by a large public and the requirements of the transition from voice-oriented systems to multimedia systems. This paper addresses some key issues concerning the IMT-2000 spectrum efficient usage and projected further developments of IMT-2000 and systems beyond. IMT-2000 is an ITU mobile standard. This paper gives the analysis of the possible implementation globally of the bands identified for IMT-2000 by the last Conference and points out the main topics studied under World Radiocommunication Conference (WRC-03) Agenda Item 1.22 on future developments of IMT-2000 and systems beyond and also under Agenda Item 1.34 on adequate protection of terrestrial services from Broadcasting Satellite Systems without constraint on the deployment and operation of terrestrial services. Preliminary studies concluded that the bands identified by World Radiocommunication Conferences (WARC-92 and WRC-2000) for IMT-2000 will be sufficient to cover spectrum requirements in major cities up to year 2010. However some additional spectrum will be needed for the future evolution of IMT- 2000 and systems beyond. Increased traffic in densely populated areas and extended coverage requirements are to be faced. It seems appropriate to address this issue already now at the time of the initial deployment of IMT-2000. The first GSM systems were introduced in the early nineties and the first identification of spectrum for IMT-2000 was done in 1992. The conceptual work for the Wire/ess World, which is the name given to the systems beyond IMT-2000 started in different groups. WWRF is one of them comprising operators of telecommunication networks, equipment and component manufacturers, academic world and develops a vision of the Wireless World. It can be expected that studies undertaken by WWRF and in particular the research on the following topics: - Increased spectrum use efficiency and flexibility; - Peak bit rate per user; - Enhanced solutions for unpaired spectrum; - Refined Multiple Access Techniques; - System Co-existence and Network Inter-working will help to improve the situation of spectrum usage and to answer the emerging need to bridge the real and the personal virtual world and to continuously stay in contact. A Wireless World of the future would become our natural enhanced living environment if there is a sufficient amount of spectrum allocated timely to the mobile services of the IMT-2000 Family and to the systems beyond IMT-2000, and if this spectrum is used in the most efficient and harmonised manner.