When third-generation (3G) systems were initially considered, the goal was to enable a single global communication standard that could fulfill the needs of anywhere and anytime communication. International Telecommunications Union’s (ITU) International Mobile Telecommunications (IMT-2000) vision (ITU-T 2000a) called for a common spectrum worldwide (1.8–2.2 GHz band), support for multiple radio environments (including cellular, satellite, cordless, and local area networks), a wide range of telecommunications services (voice, data, multimedia, and the Internet), flexible radio bearers for increased spectrum efficiency, data rates up to 2 Mbps in the initial phase, and maximum use of Intelligent Network (IN) capabilities for service development and provisioning. ITU envisioned global seamless roaming and service delivery across IMT-2000 family networks, with enhanced security and performance as well as integration of satellite and terrestrial systems to provide global coverage. Although some of the technical goals have been achieved, the dream of universal and seamless communication remains elusive. As a reflection of the regional, political, and commercial realities of the mobile communications business, the horizon of third-generation mobile communications is dominated by two largely incompatible systems.
One realization of IMT-2000 vision is called the Universal Mobile Telecommunications System (UMTS), developed under 3GPP. This system has evolved from the second generation Global System for Mobile Communications (GSM) and has gained significant support in Europe, Japan, and some parts of Asia. The system is sometimes simply referred to as the 3GPP system.
The second version of the IMT-2000 vision continues to be standardized under 3GPP2 and is referred to as the CDMA2000 or 3GPP2 system. This system has evolved from the second-generation IS-95 system and has been deployed in the United States, South Korea, Belarus, Romania, and some parts of Russia, Japan, and China, that is, mostly the regions that had IS-95 presence.
These two systems are similar in functional terms, particularly from a user’s point of view. However, they use significantly different radio access technologies and differ significantly in some of their architectural details, making them largely incompatible.
One realization of IMT-2000 vision is called the Universal Mobile Telecommunications System (UMTS), developed under 3GPP. This system has evolved from the second generation Global System for Mobile Communications (GSM) and has gained significant support in Europe, Japan, and some parts of Asia. The system is sometimes simply referred to as the 3GPP system.
The second version of the IMT-2000 vision continues to be standardized under 3GPP2 and is referred to as the CDMA2000 or 3GPP2 system. This system has evolved from the second-generation IS-95 system and has been deployed in the United States, South Korea, Belarus, Romania, and some parts of Russia, Japan, and China, that is, mostly the regions that had IS-95 presence.
These two systems are similar in functional terms, particularly from a user’s point of view. However, they use significantly different radio access technologies and differ significantly in some of their architectural details, making them largely incompatible.
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