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Second-generation telecommunication systems, such as the Global System for Mobile
Communications (GSM), enabled voice traffic to go wireless: the number of mobile phones
exceeds the number of landline phones and the mobile phone penetration is approaching
100% in several markets. The data-handling capabilities of second-generation systems are
limited, however, and third-generation systems are needed to provide the high bit-rate
services that enable high-quality images and video to be transmitted and received, and to
provide access to the Web with higher data rates.