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.
Table of Contents
1 Introduction
2 Evolution of Mobile Communications
2.1 First Generation (1G): Analog Cellular
2.2 Second Generation (2G): Multiple Digital Systems
2.3 Second to Third Generation (2G to 3G): GSM Evolution
2.4 Third Generation (3G) – IMT-2000
3 Technical Overview
3.1 Multiple Access Methods (Multiplexing) – the basis for economical use
3.1.1 Space Division Multiple Access (SDMA)
3.1.2 Time Division Multiple Access (TDMA)
3.1.3 Frequency Division Multiple Access (FDMA)
3.1.4 Code Division Multiple Access (CDMA)
3.1.4.1 Frequency Hopping Spread Spectrum (FH-SS)
3.1.4.2 Direct Sequence Spread Spectrum (DS-SS)
3.2 Structure of the GSM network
3.2.1 Radio Subsystem (RSS)
3.2.2 Network and Switching Subsystem (NSS)
3.2.3 Operation Subsystem (OSS)
4 UMTS – an international Standard
4.1 Domain Architecture of UMTS
4.1.1 User equipment (UE)
4.1.2 Utran
4.1.3 Core Network (Backbone)
4.2 Advantages of UMTS
5 Summary
Objectives and Themes
This seminar paper provides a comprehensive technical overview of mobile communication evolution, focusing on the transition from the Global System for Mobile communication (GSM) to the Universal Mobile Telecommunication System (UMTS), while examining the architectural and multiplexing shifts that enable modern mobile services.
- Historical development of mobile communication generations (1G to 3G).
- Detailed analysis of multiplexing techniques (SDMA, TDMA, FDMA, CDMA).
- Structural breakdown of the GSM network, including Radio and Switching subsystems.
- Technical architecture of UMTS, emphasizing W-CDMA and Core Network domains.
- Key performance advantages of UMTS, such as macrodiversity and load balancing.
Excerpt from the Book
Code Division Multiple Access (CDMA)
In this multiple access scheme, all users share the same frequency at the same time where the separation between the users signals are being achieved by providing codes. Each user is allocated a unique code sequence (spreading code) that is used to encode the information.
The receiver on the backhand knows the code sequence of the user and decodes the signal to recover the original information. The process steps within CDMA are shown in Figure 3.5.
When examining this scheme it becomes evident that the bandwidth of the code sequence is much larger than the bandwidth of the original information signal resulting in the fact that the encoding process enlarges the spectrum of the information signal. Therefore, the CDMA scheme is also referred to as a form of spread spectrum technology. CDMA is fairly new multiple access technique to civil applications, but has been used in military applications for many years.
Summary of Chapters
1 Introduction: Outlines the shift from 2G digital technologies to the 3G standard and sets the scope for examining GSM architecture and UMTS technology.
2 Evolution of Mobile Communications: Reviews the historical development of mobile systems from early analog standards to the emergence of global digital systems like GSM and the IMT-2000 concept.
3 Technical Overview: Details various multiplexing techniques like SDMA, TDMA, and CDMA, and provides an in-depth analysis of the GSM network’s hierarchical subsystem structure.
4 UMTS – an international Standard: Explores the domain architecture of UMTS, highlighting its transition from GSM, its radio access network (UTRAN), and technical advantages like macrodiversity.
5 Summary: Concludes with an assessment of the economic and social impacts of mobile telephony and looks ahead to future developments beyond UMTS.
Keywords
GSM, UMTS, Mobile Communication, Multiplexing, W-CDMA, TDMA, FDMA, SDMA, Network Architecture, Radio Access Network, UTRAN, Macrodiversity, Handover, Cell Breathing, IMT-2000
Frequently Asked Questions
What is the core focus of this paper?
This paper examines the evolution of mobile communication technology, specifically the transition from the widespread second-generation GSM networks to the more advanced third-generation UMTS standard.
What are the primary themes discussed?
The central themes include the historical progression of mobile generations, the mechanics of multiplexing methods, the internal structure of GSM, and the architectural domain of UMTS.
What is the primary objective of this work?
The primary objective is to provide a technical comparison between GSM and UMTS, illustrating how 3G technologies overcome the capacity and service limitations of their predecessors.
Which scientific methods are employed?
The author utilizes a descriptive and comparative research approach, analyzing standardized telecommunication documentation, network architecture models, and established signal processing theories.
What does the main body cover?
The main body covers the technical foundations of resource sharing (multiplexing), a deep dive into the GSM functional architecture, and a detailed look at the UMTS R99 release, including UTRAN and core network functions.
Which keywords characterize this paper?
Key terms include GSM, UMTS, W-CDMA, multiplexing, UTRAN, macrodiversity, and cell breathing.
How does CDMA differ from earlier methods?
Unlike TDMA or FDMA, which divide resources by time or frequency, CDMA allows all users to share the same frequency simultaneously by using unique code sequences to separate individual signals.
What is the significance of "Macrodiversity" in UMTS?
Macrodiversity allows a mobile device to communicate with multiple base stations (Node Bs) at once, reducing signal interference and improving connection quality as the device moves between cells.
Why is "Cell Breathing" an important concept?
Cell breathing describes the dynamic shrinkage of a cell's coverage area as traffic increases, which is a common consequence of interference management in systems using shared carrier frequencies like 3G.
- Quote paper
- MSc. Oliver Pausch (Author), 2006, GSM and UMTS - Excellent Past, Bright Future, Munich, GRIN Verlag, https://www.grin.com/document/69999
