Since their birth in the early seventeenth and all along their different generations, mobile communication networks have crossed important evolutionary phases aiming to define increasingly sophisticated technologies allowing the provision of seamless global roaming, quality of service, and high data rates. Today, numerous technologies are co-existing to provide a unifying set of services. Improvements in telecommunication network infrastructures, evolution of digital technologies and standardization have together made it viable to use existing data networks for multimedia applications. This clearly reverses the trend of the past where networks were dedicated to a specific application. Integration of all types of information voice, data, video and image into a single network infrastructure is known as network convergence. The end result of this convergence is commonly referred to as the next-generation network (NGN), which, conceptually anyway, combines high-speed with the best features of each network. This chapter gives the details about the details of mobile communication technology.
TopMobile Voice Telephony
First generation cellular mobile telephones developed around the world using different, incompatible analogue technologies. For example, in the 1980s in the U.S. there was the Advanced Mobile Phone System (AMPS), the U.K. had the Total Access Communications System (TACS), and Germany developed C-Netz, while Scandinavia developed the Nordic Mobile Telephone (NMT) system. The result was a wide range of largely incompatible systems, particularly in Europe, although the single AMPS system was used throughout the U.S.
Second generation (2G) mobile telephones used digital technology. The adoption of second generation technology differed substantially between the United States and Europe and reverses the earlier analogue mobile experience. In Europe, a common standard was adopted, partly due to government intervention. Global System for Mobile Communication (GSM), Code Division Multiple Access 2000 (CDMA2000), High Speed Circuit Switched Data Technology (HSCSD) Groupe Speciale Mobile (GSM) was first developed in the 1980s and was the first 2G system. But it was only in 1990 that GSM was standardized (with the new name of Global System for Mobile communication) under the auspices of the European Technical Standards Institute. The standardized GSM could allow full international roaming, automatic location services, common encryption and relatively high quality audio. GSM is now the most widely used 2G system worldwide, in more than 130 countries, using the 900 MHz frequency range. (Talukder &Yavagal, 2005).
In contrast, a variety of incompatible 2G standards developed in the United States. These include TDMA, a close relative of GSM, and CDMA, referring to Time and Code Division Multiple Access respectively. These technologies differ in how they break down calls to allow for more efficient use of spectrum within a single cell.
The next technology which lies between 2G and 3G is 2.5G. General Packet Radio System (GPRS) Enhanced Data Rate for GSM Evolution (EDGE).
The next stage in the development of mobile telephones is the move to third generation (3G) technology, Universal Mobile Telephone Standard (UMTS). These systems allow for significantly increased speeds of transmission and are particularly useful for data services. For example, 3G phones can more efficiently be used for e-mail services, and downloading content (such as music and videos) from the internet. They can also allow more rapid transmission of images, for example from camera phones.