8.1 General Discussion

A one-sentence description of the 3GPP concept might be: "a CDMA packet-based air interface combined with a GSM + GPRS core network." ITU's 3G concept, known as IMT-2000, includes several other accepted technologies for 3G systems. However, the referenced WCDMA + GSM combination will be the most widely used. The simple reason for this is the fact that among the second-generation mobile cellular networks, GSM is by far the most widely used technology. All of the significant 3G proposals for IMT-2000 are those that successfully protect the investments in their 2G legacy networks in a 3G world. The 3GPP work strives to protect the GSM investments and bring the markets into 3G. The present-day operators will not want to invest in new networks if they can "recycle" their existing GSM networks. Most big network manufacturers and operators are actively supporting this approach. So for these operators this 3G solution is a good deal, because they can continue to use their upgraded GSM networks. In many cases the radio access network can be updated to conform to the 3G requirements. The mobile phone users however are not so lucky, as they will need new phones that are capable of accessing WCDMA base stations. Most probably, these phones will have to be dual-system GSM + WCDMA phones at first, since the UTRAN radio access network coverage will be quite limited at service launch. The UTRAN may only provide coverage in urban hot-spots in the beginning, as the old GSM...