The third generation of mobile telephony to be deployed. The first generation, AMPS, emerged in the 1980s and was based on analogue signals. The second generation moved to the use of digital voice encoding in the 1990s, with two incompatible standards, CDMA and GSM. The third generation, introduced in 1998, saw a series of improvements in bandwidth and digital data-handling to support mobile Internet access that facilitated the emergence of the smartphone. 3G is governed by a number of ITU standards. See also 4G LTE.