Cell searching in WCDMA

In Europe, the digital second generation (2G) systems, IS-136 and the Global System for Mobile communications (GSM), developed were based on time division multiple access (TDMA) and in the US, the IS-95 system developed was based on code division multiple access (CDMA). The 2G technologies developed both in Europe and US suffered from a number of limitations that included: low bit rate for 2G systems and non-interoperability between the standards. The low bit rate for 2G systems could not meet subscriber demands for new and faster non-voice services while on the move. Hence, the third generation (3G) systems were developed with the aim to solve these problems by promising global roaming across 3G standards, as well as support for multimedia applications. These 3G services are based on CDMA.