 Terrestrial Broadband Wireless Telecommunications Beyond 4G AMPS/NAMPS WCDMA Advanced LTE (FDMA/FDD) (TDMA/FDD) (CDMA/FDD) (OFDMA/FDD) (OFDMA/FDD) TACS/ETACS D-AMPS TD-CDMA, TD-LTE Advanced (FDMA/FDD) (TDMA/FDD) TD-SCDMA (OFDMA/TDD) TD-LTE (CDMA/TDD) WiMAX (OFDMA/TDD) (FDMA/FDD) (TDMA/FDD) CDMA-2000 (OFDMA/TDD) HiCaps IS-95 (CDMA/FDD) (FDMA/FDD) (CDMA/FDD) B-Netz/C-Netz (CDMA/FDD) (FDMA/FDD) (TDMA/TDD) Figure 10.8 Successive generations of mobile telecommunications systems The generational transitions are generally characterised as follows: 1G to 2G evolution with the shift from analogue to digital 2G to 3G evolution with the introduction of data communications, higher transmission rates, and packet switching 3G to 4G evolution with the provision of mobile broadband services, full packet-switching technologies, and advanced network architecture. A number of standards broadly associated with these four generations are shown in Figure 10.8. Some of these standards did not succeed in the marketplace and were not widely rolled out. Some standards evolved across generations and remain in operation, while evolution of some standards failed to succeed. All 1G, most of the 2G and a number of 3G systems have been phased out, and 4G systems are now being rolled out globally. A number of duplexing and multiple access technologies were used in the four generations to date and beyond. These will be discussed in detail below. The process of standardisation for the fifth generation of mobile communications systems (5G) has started, with a target roll-out data of 2020 [5]. Nodes in a Mobile Telecommunications System A number of networking devices are necessary to connect a mobile device to the public tele- communications system and to other mobile devices. The network generally consists of the mobile device (or user equipment - UE as known in some 3G/4G standards), base stations (or 'node-B' as known in some 3G/4G standards) and a central network, also known as the core network, which controls the base stations and interfaces t