GSM and UMTS - Excellent Past, Bright Future

Since the beginning of the 1990s the mobile telecommunication sector to mention the cellular communication services has continued to grow and evolved strongly. The reason for such an unprecedented level of development was possible with the existence of the so-called second generation digital technologies, with GSM (Global System for Mobile communication) being one of the most popular systems. In fact these second generation digital technologies, which are generally incompatible with each other, went eventually through standardization processes since the beginning of the 1980s reaching their limits of possibilities by now.
In order to be able to offer new services and to provide users with real mobility on a global scale, it has become essential to augment the technology and elevate the threshold to the so-called third generation technology. The following paper will first provide a short but more thorough historical overview of the developments in the cellular communication services. The second part will be exemplifying the technology behind GSM. In this part, the paper will first address the technologies used to provide wireless voice and data services to subscribers commonly referred to as multiplexing. Followed by examining the structure of the GSM net-work itself. The last main part will focus on the third generation technology by showcasing the widely used Universal Mobile Telecommunication System (UMTS). This part will not only introduce the technology by looking at the architecture in detail, but also determine some of the differences to the GSM technology and address the overall advantages. Finally, the paper will be summarized.