Generations of mobile user

The first generation:
The first handheld mobile phone to become commercially available to the US market was the Motorola Dyna TAC 8000X, which received approval in 1983. Mobile phones began to proliferate through the 1980s with the introduction of "cellular" phones based on cellular networks with multiple base stations located relatively close to each other, and protocols for the automated "handover" between two cells when a phone moved from one cell to the other. At this time analog transmission was in use in all systems. Mobile phones were somewhat larger than current ones, and at first, all were designed for permanent installation in vehicles (hence the term car phone). Soon, some of these bulky units were converted for use as "transportable" phones the size of a briefcase. Motorola introduced the first truly portable, handheld phone. These systems (NMT, AMPS, TACS, RTMI, C-Netz, and Radiocom 2000) later became known as first generation (1G) mobile phones.

The second generation:
In the 1990s, 'second generation' (2G) mobile phone systems such as GSM, IS-136 ("TDMA"), iDEN and IS-95 ("CDMA") began to be introduced. The first digital cellular phone call was made in the United States in 1990, in 1991 the first GSM network (Radiolinja) opened in Finland. 2G phone systems were characterized by digital circuit switched transmission and the introduction of advanced and fast phone to network signaling. In general the frequencies used by 2G systems in Europe were higher though with some overlap, for example the 900 MHz frequency range was used for both 1G and 2G systems in Europe and so such 1G systems were rapidly closed down to make space for 2G systems. In America the IS-54 standard was deployed in the same band as AMPS and displaced some of the existing analog channels.
Coinciding with the introduction of 2G systems was a trend away from the larger "brick" phones toward tiny 100–200g hand-held devices, which soon became the norm. This change was possible through technological improvements such as more advanced batteries and more energy-efficient electronics, but also was largely related to the higher density of cellular sites caused by increasing usage levels which decreased the demand for high transmit powers to reach distant towers for customers to be satisfied.

The third generation:
Not long after the introduction of 2G networks, projects began to develop third generation (3G) systems. Inevitably there were many different standards with different contenders pushing their own technologies. Quite differently from 2G systems, however, the meaning of 3G has been standardized in the IMT-2000 standardization processing. This process did not standardize on a technology, but rather on a set of requirements (2 Mbit/s maximum data rate indoors, 384 kbit/s outdoors, for example). At that point, the vision of a single unified worldwide standard broke down and several different standards have been introduced.
During the development of 3G systems, 2.5G systems such as CDMA2000 1x and GPRS were developed as extensions to existing 2G networks. These provide some of the features of 3G without fulfilling the promised high data rates or full range of multimedia services. CDMA2000-1X delivers theoretical maximum data speeds of up to 307 kbit/s. Just beyond these is the EDGE system which in theory covers the requirements for 3G system, but is so narrowly above these that any practical system would be sure to fall short.
At the beginning of the 21st century, 3G mobile phone systems such as UMTS and CDMA2000 1xEV-DO have now begun to be publicly available. The final success of these systems is still to be determined.
Live streaming of radio and television to 3G handsets is one future direction for the industry, with companies from Real and Disney recently announcing services.

The raft of all-singing, all-dancing phones announced at or just before 3GSM have a strong focus on multimedia, especially cameras, video, and music. Even the most basic, entry-level handsets -- the ones most likely to be offered for free with contracts by mobile operators -- are now featuring VGA-quality displays. Higher-end multimedia phones are starting to be equipped with hard drives and gigabytes of flash memory. That sets them up to do battle with Apple's iPod.

Another hot trend at 3GSM is called unlicensed mobile access, or UMA. (We're not kidding about the acronyms.) UMA is a scheme that allows phones and other portable devices to communicate over both cellular and wireless LAN networks (Wi-Fi), seamlessly handing off calls from one to the other. Major mobile-phone makers, including Nokia and Sony Ericsson, have introduced phones that can conveniently operate on both types of networks.