Evolution of mobile cellular communication systems. The journey to UMTS

By the year 2002, it is anticipated that 1 billion people will be generating over 50% of the revenues of mobile communication systems from the packet data exchanges, (Internet activities, fax, voice mail and mobile office applications). However the highest growth of the data transfer volume will be produced from the Internet access, for which the existing GSM access will not be able to support. Additionally the mobile networks will have to support real-time applications like voice and multimedia based on IP as currently available on the fixed networks. This growing demand for higher bandwidth and real-time data packet services will have to be the main basic requirements for 3/sup rd/ generation (3G) mobile networks. It is important that an evolutionary approach should be adopted in modifying GSM networks in steps in order to enable the provision of the new services required. The first step in the evolution is through the addition of a GPRS backbone network with the benefits of an IP based packet network and the potential of WAP protocols for developing Internet content browsing (cellphone microbrowsers). The follow up from GPRS will be achieved from GPRS but with a higher access speeds and new processing techniques. GSM can also evolve to a 3G using yet another route, wideband CDMA, which is reviewed. This paper attempts to put the pieces of this puzzle together and review, in the process, various proposals required to launch the family of new generation mobile systems namely: the air interface technology, the core network structure, the new services, new technologies on offer and challenges awaiting all concerned.