Potential of the GSM air interface to support CDMA operation

An important issue in the development of third generation systems is the need for compatibility with the existing second generation systems. This paper considers the feasibility of supporting CDMA operation within the GSM air interface in order to provide UMTS capabilities. It produces performance estimates for two specific examples: joint detection CDMA channels, and multicarrier DS-CDMA channels. It is shown that a number of advantages can be obtained by using a hybrid CDMA scheme.